Spacecraft ceramic protective shield
NASA Technical Reports Server (NTRS)
Larriva, Rene F. (Inventor); Nelson, Anne (M.); Czechanski, James G. (Inventor); Poff, Ray E. (Inventor)
1995-01-01
A low areal density protective shield apparatus, and method for making same, for protecting spacecraft structures from impact with hypervelocity objects, including a bumper member comprising a bumper ceramic layer, a bumper shock attenuator layer, and a bumper confining layer. The bumper ceramic layer can be SiC or B.sub.4 C; the bumper shock attenuator layer can be zirconia felt; and the bumper confining layer can be aluminum. A base armor member can be spaced from the bumper member and a ceramic fiber-based curtain can be positioned between the bumper and base armor members.
Comparison of strain rates of dart impacted plaques and pendulum impacted bumpers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scammell, K.L.
1987-01-01
The difference in strain rates prevailing during pendulum impact of bumpers versus high speed dart impact of plaques was investigated. Uni-axial strain gages were applied to the tension side of the plaques and bumpers directly opposite the point of impact. The plaques were impacted with an instrumented high rate dart impact tester and the bumpers impacted with a full scale bumper pendulum impact tester. Theoretical calculations and actual strain rate data support the conclusion that the strain rate of a plaque during dart impact significantly exceeds that of bumper strain rate during pendulum impact.
Hypervelocity impact response of aluminum multi-wall structures
NASA Technical Reports Server (NTRS)
Schonberg, William P.; Bean, Alan J.
1991-01-01
The results of an investigation in which the perforation resistance of aluminum multiwall structures is analyzed under a variety of hypervelocity impact loading conditions are presented. A comparative analysis of the impact damage in structural systems with two or more bumpers and the damage in single-bumper systems of similar weight is performed to determine the advantages and disadvantages of employing more than one bumper in structural wall systems for long-duration spacecraft. A significant increase in protection against perforation by hypervelocity projectiles can be achieved if a single bumper is replaced by two bumpers of similar weight while the total wall spacing is kept constant. It is found that increasing the number of bumpers beyond two while keeping the total stand-off distance constant does not result in a substantial increase in protection over that offered by two bumpers of similar weight.
NASA Technical Reports Server (NTRS)
Hoerz, Friedrich; Cintala, Mark; See, Thomas; Bernhard, Ronald; Cardenas, Frank; Davidson, William; Haynes, Jerry
1992-01-01
An experimental inquiry into the utility of discontinuous bumpers was conducted to investigate the collisional outcomes of impacts into single grid-like targets and to compare the results with more traditional bumper designs that employ continuous sheet stock. We performed some 35 experiments using 6.3 and 3.2 mm diameter spherical soda-lime glass projectiles at low velocities (less than 2.5 km/s) and 13 at velocities between 5 and 6 km/s, using 3.2 mm spheres only. The thrust of the experiments related to the characterization of collisional fragments as a function of target thickness or areal shield mass of both bumper designs. The primary product of these experiments was witness plates that record the resulting population of collisional fragments. Substantial interpretive and predictive insights into bumper performance were obtained. All qualitative observations (on the witness plates) and detailed measurements of displaced masses seem simply and consistently related only to bumper mass available for interaction with the impactor. This renders the grid bumper into the superior shield design. These findings present evidence that discontinuous bumpers are a viable concept for collisional shields, possibly superior to continuous geometries.
Crashworthiness Design for Bionic Bumper Structures Inspired by Cattail and Bamboo.
Xu, Tao; Liu, Nian; Yu, Zhenglei; Xu, Tianshuang; Zou, Meng
2017-01-01
Many materials in nature exhibit excellent mechanical properties. In this study, we evaluated the bionic bumper structure models by using nonlinear finite element (FE) simulations for their crashworthiness under full-size impact loading. The structure contained the structural characteristics of cattail and bamboo. The results indicated that the bionic design enhances the specific energy absorption (SEA) of the bumper. The numerical results showed that the bionic cross-beam and bionic box of the bionic bumper have a significant effect on the crashworthiness of the structure. The crush deformation of bionic cross-beam and box bumper model was reduced by 33.33%, and the total weight was reduced by 44.44%. As the energy absorption capacity under lateral impact, the bionic design can be used in the future bumper body.
Crashworthiness Design for Bionic Bumper Structures Inspired by Cattail and Bamboo
Xu, Tao; Liu, Nian
2017-01-01
Many materials in nature exhibit excellent mechanical properties. In this study, we evaluated the bionic bumper structure models by using nonlinear finite element (FE) simulations for their crashworthiness under full-size impact loading. The structure contained the structural characteristics of cattail and bamboo. The results indicated that the bionic design enhances the specific energy absorption (SEA) of the bumper. The numerical results showed that the bionic cross-beam and bionic box of the bionic bumper have a significant effect on the crashworthiness of the structure. The crush deformation of bionic cross-beam and box bumper model was reduced by 33.33%, and the total weight was reduced by 44.44%. As the energy absorption capacity under lateral impact, the bionic design can be used in the future bumper body. PMID:29118571
Spacecraft wall design for increased protection against penetration by space debris impacts
NASA Technical Reports Server (NTRS)
Schonberg, William P.; Tullos, Randy J.
1990-01-01
All orbiting spacecraft are susceptible to impacts by meteoroids and pieces of orbital space debris. These impacts occur at extremely high speeds and can damage flight-critical systems, which can in turn lead to catastrophic failure of the spacecraft. The design of a spacecraft for a long-duration mission into the meteoroid and space debris environment must include adequate protection against perforation of pressurized components by such impacts. This paper presents the results of an investigation into the perforation resistance of dual-wall structural systems fabricated with monolithic bumper plates and with corrugated bumper plates of equal weight. A comparative analysis of the impact damage in dual-wall systems with corrugated bumper specimens and that in dual-wall specimens with monolithic bumpers of similar weight is performed to determine the advantages and disadvantages of employing corrugated bumpers in structural wall systems for long-duration spacecraft. The analysis indicates that a significant increase in perforation protection can be achieved if a monolithic bumper is replaced by a corrugated bumper of equal weight. The parameters of the corrugations in the corrugated bumper plates are optimized in a manner that minimizes the potential for the creation of ricochet debris in the event of an oblique hypervelocity impact. Several design examples using the optimization scheme are presented and discussed.
Micrometeoroid and Orbital Debris Risk Assessment With Bumper 3
NASA Technical Reports Server (NTRS)
Hyde, J.; Bjorkman, M.; Christiansen, E.; Lear, D.
2017-01-01
The Bumper 3 computer code is the primary tool used by NASA for micrometeoroid and orbital debris (MMOD) risk analysis. Bumper 3 (and its predecessors) have been used to analyze a variety of manned and unmanned spacecraft. The code uses NASA's latest micrometeoroid (MEM-R2) and orbital debris (ORDEM 3.0) environment definition models and is updated frequently with ballistic limit equations that describe the hypervelocity impact performance of spacecraft materials. The Bumper 3 program uses these inputs along with a finite element representation of spacecraft geometry to provide a deterministic calculation of the expected number of failures. The Bumper 3 software is configuration controlled by the NASA/JSC Hypervelocity Impact Technology (HVIT) Group. This paper will demonstrate MMOD risk assessment techniques with Bumper 3 used by NASA's HVIT Group. The Permanent Multipurpose Module (PMM) was added to the International Space Station in 2011. A Bumper 3 MMOD risk assessment of this module will show techniques used to create the input model and assign the property IDs. The methodology used to optimize the MMOD shielding for minimum mass while still meeting structural penetration requirements will also be demonstrated.
Simulation and Failure Analysis of Car Bumper Made of Pineapple Leaf Fiber Reinforced Composite
NASA Astrophysics Data System (ADS)
Arbintarso, E. S.; Muslim, M.; Rusianto, T.
2018-02-01
The bumper car made of the Pineapple Leaf Fiber Reinforced Composite (PLFRC) is possible to be produced with the advantage of easy to get, and cheap. Pineapple leaf fiber has chosen as a natural fiber, which the maximum of the strength of 368 MPa. The objective of this study was to determine the maximum capability of front car bumpers using Pineapple Leaf Fiber Reinforced Composite materials through the process of simulating stress analysis with Solidworks 2014 software. The aim also to know the distribution of loads that occur on the front car bumper and predict the critical point position on the design of the bumper. The result will use to develop the alternative lightweight, cheap and environmentally friendly materials in general and the development of the use of pineapple fiber for automotive purposes in particular. Simulations and failure analysis have been conducted and showed an increased impact speed in line with increased displacement, strain, and stress that occur on the surface of the bumper. The bumper can withstand collisions at a speed of less than 70 kph.
Coultas, Thomas A.
1977-01-01
Operation of a plasma device such as a reactor for controlled thermonuclear fusion is facilitated by an improved bumper wall enclosing the plasma to smooth the flow of energy from the plasma as the energy impinges upon the bumper wall. The bumper wall is flexible to withstand unequal and severe thermal shocks and it is readily replaced at less expense than the cost of replacing structural material in the first wall and blanket that surround it.
DOT National Transportation Integrated Search
1996-01-01
This fact sheet, NHTSA Facts: Summer 1996, discusses automobile bumpers. It notes that a car bumper is not a safety device to prevent or reduce injuries to people in the car. Instead, it is designed to protect the hood, trunk, grille, parking lights,...
NASA Astrophysics Data System (ADS)
Ryan, Shannon; Christiansen, Eric L.
2013-02-01
A series of 66 hypervelocity impact experiments have been performed to assess the potential of various materials (aluminium, titanium, copper, stainless steel, nickel, nickel/chromium, reticulated vitreous carbon, silver, ceramic, aramid, ceramic glass, and carbon fibre) and structures (monolithic plates, open-cell foam, flexible fabrics, rigid meshes) for micrometeoroid and orbital debris (MMOD) shielding. Arranged in various single-, double-, and triple-bumper configurations, screening tests were performed with 0.3175 cm diameter Al2017-T4 spherical projectiles at nominally 6.8 km/s and normal incidence. The top performing shields were identified through target damage assessments and their respective weight. The top performing candidate shield at the screening test condition was found to be a double-bumper configuration with a 0.25 mm thick Al3003 outer bumper, 6.35 mm thick 40 PPI aluminium foam inner bumper, and 1.016 mm thick Al2024-T3 rear wall (equal spacing between bumpers and rear wall). In general, double-bumper candidates with aluminium plate outer bumpers and foam inner bumpers were consistently found to be amongst the top performers. For this impact condition, potential weight savings of at least 47% over conventional all-aluminium Whipple shields are possible by utilizing the investigated materials and structures. The results of this study identify materials and structures of interest for further, more in-depth, impact investigations.
NASA Astrophysics Data System (ADS)
Song, Zhen; Moore, Kevin L.; Chen, YangQuan; Bahl, Vikas
2003-09-01
As an outgrowth of series of projects focused on mobility of unmanned ground vehicles (UGV), an omni-directional (ODV), multi-robot, autonomous mobile parking security system has been developed. The system has two types of robots: the low-profile Omni-Directional Inspection System (ODIS), which can be used for under-vehicle inspections, and the mid-sized T4 robot, which serves as a ``marsupial mothership'' for the ODIS vehicles and performs coarse resolution inspection. A key task for the T4 robot is license plate recognition (LPR). For a successful LPR task without compromising the recognition rate, the robot must be able to identify the bumper locations of vehicles in the parking area and then precisely position the LPR camera relative to the bumper. This paper describes a 2D-laser scanner based approach to bumper identification and laser servoing for the T4 robot. The system uses a gimbal-mounted scanning laser. As the T4 robot travels down a row of parking stalls, data is collected from the laser every 100ms. For each parking stall in the range of the laser during the scan, the data is matched to a ``bumper box'' corresponding to where a car bumper is expected, resulting in a point cloud of data corresponding to a vehicle bumper for each stall. Next, recursive line-fitting algorithms are used to determine a line for the data in each stall's ``bumper box.'' The fitting technique uses Hough based transforms, which are robust against segmentation problems and fast enough for real-time line fitting. Once a bumper line is fitted with an acceptable confidence, the bumper location is passed to the T4 motion controller, which moves to position the LPR camera properly relative to the bumper. The paper includes examples and results that show the effectiveness of the technique, including its ability to work in real-time.
Landsat-5 bumper-mode geometric correction
Storey, James C.; Choate, Michael J.
2004-01-01
The Landsat-5 Thematic Mapper (TM) scan mirror was switched from its primary operating mode to a backup mode in early 2002 in order to overcome internal synchronization problems arising from long-term wear of the scan mirror mechanism. The backup bumper mode of operation removes the constraints on scan start and stop angles enforced in the primary scan angle monitor operating mode, requiring additional geometric calibration effort to monitor the active scan angles. It also eliminates scan timing telemetry used to correct the TM scan geometry. These differences require changes to the geometric correction algorithms used to process TM data. A mathematical model of the scan mirror's behavior when operating in bumper mode was developed. This model includes a set of key timing parameters that characterize the time-varying behavior of the scan mirror bumpers. To simplify the implementation of the bumper-mode model, the bumper timing parameters were recast in terms of the calibration and telemetry data items used to process normal TM imagery. The resulting geometric performance, evaluated over 18 months of bumper-mode operations, though slightly reduced from that achievable in the primary operating mode, is still within the Landsat specifications when the data are processed with the most up-to-date calibration parameters.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-03
... Subject to the Federal Motor Vehicle Safety, Bumper, and Theft Prevention Standards. OMB Number: 2127-0002... Federal motor vehicle safety, bumper, and theft prevention standards administered by NHTSA. The... vehicles and motor vehicle equipment subject to the Federal motor vehicle safety, bumper, and theft...
Overview Of Recent Enhancements To The Bumper-II Meteoroid and Orbital Debris Risk Assessment Tool
NASA Technical Reports Server (NTRS)
Hyde, James L.; Christiansen, Eric L.; Lear, Dana M.; Prior, Thomas G.
2006-01-01
Discussion includes recent enhancements to the BUMPER-II program and input files in support of Shuttle Return to Flight. Improvements to the mesh definitions of the finite element input model will be presented. A BUMPER-II analysis process that was used to estimate statistical uncertainty is introduced.
Joining and reinforcing a composite bumper beam and a composite crush can for a vehicle
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berger, Elisabeth; Decker, Leland; Armstrong, Dale
A front bumper beam and crush can (FBCC) system is provided for a vehicle. A bumper beam has an interior surface with a plurality of ribs extending therefrom. The ribs and the interior surface are made of a chopped fiber composite and cooperate to engage a crush can. The chopped fiber composite reinforces the engaging surfaces of the crush can and the interior surface of the bumper beam. The crush can has a tubular body made of a continuous fiber composite. The crush can has outwardly-extending flanges at an end spaced away from the bumper beam. The flanges are atmore » least partially provided with a layer of chopped fiber composite to reinforce a joint between the outwardly-extending flange and the vehicle frame.« less
Uncertainty Considerations for Ballistic Limit Equations
NASA Technical Reports Server (NTRS)
Schonberg, W. P.; Evans, H. J.; Williamsen, J. E.; Boyer, R. L.; Nakayama, G. S.
2005-01-01
The overall risk for any spacecraft system is typically determined using a Probabilistic Risk Assessment (PRA). A PRA attempts to determine the overall risk associated with a particular mission by factoring in all known risks (and their corresponding uncertainties, if known) to the spacecraft during its mission. The threat to mission and human life posed by the mircro-meteoroid & orbital debris (MMOD) environment is one of the risks. NASA uses the BUMPER II program to provide point estimate predictions of MMOD risk for the Space Shuttle and the International Space Station. However, BUMPER II does not provide uncertainty bounds or confidence intervals for its predictions. With so many uncertainties believed to be present in the models used within BUMPER II, providing uncertainty bounds with BUMPER II results would appear to be essential to properly evaluating its predictions of MMOD risk. The uncertainties in BUMPER II come primarily from three areas: damage prediction/ballistic limit equations, environment models, and failure criteria definitions. In order to quantify the overall uncertainty bounds on MMOD risk predictions, the uncertainties in these three areas must be identified. In this paper, possible approaches through which uncertainty bounds can be developed for the various damage prediction and ballistic limit equations encoded within the shuttle and station versions of BUMPER II are presented and discussed. We begin the paper with a review of the current approaches used by NASA to perform a PRA for the Space Shuttle and the International Space Station, followed by a review of the results of a recent sensitivity analysis performed by NASA using the shuttle version of the BUMPER II code. Following a discussion of the various equations that are encoded in BUMPER II, we propose several possible approaches for establishing uncertainty bounds for the equations within BUMPER II. We conclude with an evaluation of these approaches and present a recommendation regarding which of them would be the most appropriate to follow.
Bumper 3 Update for IADC Protection Manual
NASA Technical Reports Server (NTRS)
Christiansen, Eric L.; Nagy, Kornel; Hyde, Jim
2016-01-01
The Bumper code has been the standard in use by NASA and contractors to perform meteoroid/debris risk assessments since 1990. It has undergone extensive revisions and updates [NASA JSC HITF website; Christiansen et al., 1992, 1997]. NASA Johnson Space Center (JSC) has applied BUMPER to risk assessments for Space Station, Shuttle, Mir, Extravehicular Mobility Units (EMU) space suits, and other spacecraft (e.g., LDEF, Iridium, TDRS, and Hubble Space Telescope). Bumper continues to be updated with changes in the ballistic limit equations describing failure threshold of various spacecraft components, as well as changes in the meteoroid and debris environment models. Significant efforts are expended to validate Bumper and benchmark it to other meteoroid/debris risk assessment codes. Bumper 3 is a refactored version of Bumper II. The structure of the code was extensively modified to improve maintenance, performance and flexibility. The architecture was changed to separate the frequently updated ballistic limit equations from the relatively stable common core functions of the program. These updates allow NASA to produce specific editions of the Bumper 3 that are tailored for specific customer requirements. The core consists of common code necessary to process the Micrometeoroid and Orbital Debris (MMOD) environment models, assess shadowing and calculate MMOD risk. The library of target response subroutines includes a board range of different types of MMOD shield ballistic limit equations as well as equations describing damage to various spacecraft subsystems or hardware (thermal protection materials, windows, radiators, solar arrays, cables, etc.). The core and library of ballistic response subroutines are maintained under configuration control. A change in the core will affect all editions of the code, whereas a change in one or more of the response subroutines will affect all editions of the code that contain the particular response subroutines which are modified. Note that the Bumper II program is no longer maintained or distributed by NASA.
Content-Based Analysis of Bumper Stickers in Jordan
ERIC Educational Resources Information Center
Jaradat, Abdullah A.
2016-01-01
This study has set out to investigate bumper stickers in Jordan focusing mainly on the themes of the stickers. The study hypothesized that bumper stickers in Jordan reflect a wide range of topics including social, economic, and political. Due to being the first study of this phenomenon, the study has adopted content-based analysis to determine the…
Study design and analysis of automobile bumper for pedestrian safety
NASA Astrophysics Data System (ADS)
Kulkarni, Akash; Vora, Rushabh; Ravi, K.
2017-11-01
This paper aims to design and analyse the bumper beam structure, in order to ensure the protection of the pedestrians along with the occupants inside the vehicle. The concern shown towards the pedestrian safety is because, each year about 2,70,000 pedestrians are killed in road accidents that accounts to 22% of the total deaths. From the literature review, it was inferred that the mounting position of bumper and material selection play a crucial role in maximising the pedestrian safety. Hence in this paper, the effects of bumper mounting position and the bumper beam material have been studied, with reference to an explicit dynamic collision involving with a dummy human lower leg set-up. The acceptance of a particular mounting position/material was based on the fact that the maximum stress and deformation induced were less than the yield limits of the human leg form structure (representing the skin, femur and tibia).
NASA Technical Reports Server (NTRS)
1995-01-01
The HEX bumper was originally developed for use with the Defensive Shields Demonstration (DSD) Program. The University of Dayton Research Institute was a subcontractor to the Martin Marietta Astronautics Group in Denver Colorado at the time the HEX bumper was designed for use on the DSD Program. The design originated at the University and was essentially made available to interested parties. All HEX bumpers used in the DSD Program were fabricated at the University by rolling sheet stock through a special set of rollers. Two pieces of 3003-H14 aluminum sheet were rolled to produce the bumpers evaluated in Shots 4-1302 and 4-1304. A brief summary of the results of these tests is given in below. Contact prints of the multiple-exposure, orthogonal view radiographs of the debris clouds produced by the tests are attached. A sketch of the HEX bumper design is also attached.
NASA Astrophysics Data System (ADS)
Myagkov, N. N.; Shumikhin, T. A.; Bezrukov, L. N.
2013-08-01
The series of impact experiments were performed to study the properties of ejecta generated at high-velocity perforation of thin bumpers. The bumpers were aluminum plates, fiber-glass plastic plates, and meshes weaved of steel wire. The projectiles were 6.35 mm diameter aluminum spheres. The impact velocities ranged from 1.95 to 3.52 km/s. In the experiments the ejecta particles were captured with low-density foam collectors or registered with the use of aluminum foils. The processing of the experimental results allowed us to estimate the total masses, spatial and size distributions, and perforating abilities of the ejecta produced from these different bumpers. As applied to the problem of reducing the near-Earth space pollution caused by the ejecta, the results obtained argue against the use of aluminum plates as first (outer) bumper in spacecraft shield protection.
49 CFR Appendix B to Part 591 - Section 591.5(f) Bond for the Entry of More Than a Single Vehicle
Code of Federal Regulations, 2010 CFR
2010-10-01
...) IMPORTATION OF VEHICLES AND EQUIPMENT SUBJECT TO FEDERAL SAFETY, BUMPER AND THEFT PREVENTION STANDARDS Pt. 591... Federal motor vehicle safety, or bumper, or theft prevention standards; and WHEREAS, pursuant to 49 CFR... to conform to the Federal motor vehicle safety, bumper, and theft prevention standards; and WHEREAS...
Estimating potential Engelmann spruce seed production on the Fraser Experimental Forest, Colorado
Robert R. Alexander; Carleton B. Edminster; Ross K. Watkins
1986-01-01
Two good, three heavy, and two bumper spruce seed crops were produced during a 15-year period. There was considerable variability in seed crops, however. Not all locations produced good to bumper seed crops when overall yearly ratings averaged good or better; conversely, some locations produced bumper seed crops in 3 or more years. Mathematical relationships,...
Will the light truck bumper height-matching standard reduce deaths in cars?
Ossiander, Eric M; Koepsell, Thomas D; McKnight, Barbara
2013-03-01
In a collision between a car and a sport utility vehicle (SUV) or pickup truck, car occupants are more likely to be killed than if they crashed with another car. Some of the excess risk may be due to the propensity of SUVs and pickups with high bumpers to override the lower bumpers in cars. To reduce this incompatibility, particularly in head-on collisions, in 2003 automobile manufacturers voluntarily established a bumper height-matching standard for pickups and SUVs. To assess whether height-matching bumpers in pickups and SUVs were associated with the risk of death in either car occupants or pickup and SUV occupants. Case-control study of collisions between one car and one SUV or pickup in the US during 2000-2008, in which the SUV or pickup was model year 2000-2006. Cases were all decedents in fatal crashes; one control was selected from each crash in a national probability sample of crashes. Occupants of cars that crashed with SUVs or pickups with height-matching bumpers may be at slightly reduced risk of death compared to those that crashed with other SUVs or pickups (adjusted odds ratio: 0.83 (95% confidence interval 0.61-1.13)). There was no evidence of a reduction in risk in head-on crashes (1.09 (0.66-1.79)). In crashes in which the SUV or pickup struck the car on the side, height-matched bumpers were associated with a reduced risk of death (0.68 (0.48-0.97)). Occupants of SUVs and pickups with height-matching bumpers may also be at slightly reduced risk of death (0.91 (0.64-1.28)). Height-matching bumpers were associated with a reduced risk of death among car occupants in crashes in which SUVs or pickups struck cars in the side, but there was little evidence of an effect in head-on crashes. The new bumper height-matching standard may not achieve its primary goal of reducing deaths in head-on crashes, but may modestly reduce overall deaths in crashes between cars and SUVs or pickups because of unanticipated benefits to car occupants in side crashes, and a possible beneficial effect to SUV and pickup occupants. Copyright © 2012 Elsevier Ltd. All rights reserved.
1950-02-24
Bumper Wac liftoff at the Long Range Proving Ground located at Cape Canaveral, Florida. At White Sands, New Mexico, the German rocket team experimented with a two-stage rocket called Bumper Wac, which intended to provide data for upper atmospheric research. On February 24, 1950, the Bumper, which employed a V-2 as the first stage with a Wac Corporal upper stage, obtained a peak altitude of more than 240 miles.
Safeguarding a Lunar Rover with Wald's Sequential Probability Ratio Test
NASA Technical Reports Server (NTRS)
Furlong, Michael; Dille, Michael; Wong, Uland; Nefian, Ara
2016-01-01
The virtual bumper is a safeguarding mechanism for autonomous and remotely operated robots. In this paper we take a new approach to the virtual bumper system by using an old statistical test. By using a modified version of Wald's sequential probability ratio test we demonstrate that we can reduce the number of false positive reported by the virtual bumper, thereby saving valuable mission time. We use the concept of sequential probability ratio to control vehicle speed in the presence of possible obstacles in order to increase certainty about whether or not obstacles are present. Our new algorithm reduces the chances of collision by approximately 98 relative to traditional virtual bumper safeguarding without speed control.
Evaluation of a knee-kicker bumper design for reducing knee morbidity among carpet layers.
Huang, Wan-Fu; Wu, Chih-Fu
2012-09-01
Carpet layers have a high prevalence of occupational knee morbidity. One of the main causes is that they need to frequently 'kick' the bumper on the rear end of the knee kicker with one knee when laying a carpet. Considering the bumper's marked effects on kicking force transmission and safety, this study aims to improve the design of the knee-kicker bumper by reducing the risk factors. An improved pendulum-type impact-testing platform was designed as an evaluative apparatus, with the impulse and the coefficient of restitution serving as evaluative criteria. The newly developed bumper has improved firmness from drilled blind holes and an increase in effective forward force of 15%-138%, which implies lower operational demands and a lighter knee burden (i.e., less kicking energy results in the same work efficiency), and a softer contact surface that enhances operating comfort. The newly designed kicker was positively reviewed by subjects. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.
1999-08-24
At Cape Canaveral Air Station's (CCAS) Complex 3/4, officials held a ceremony kicking off a year-long series of events commemorating 50 years of launches from the Space Coast that began with the Bumper rockets. At right, Norris Gray, a Bumper Program veteran, unveils a street sign that will be used to mark the road leading to the launch complex from which Bumper was launched. Seen on the stage are, left to right, Lt. Col. Randall K. Horn (at the podium), Commander, CCAS; Congressman David Weldon, 15th Congressional District of the State of Florida; Lieutenant Governor of the State of Florida Frank T. Brogan; Center Director Roy D. Bridges; and Executive Director Edward F. Gormel, Joint Performance Management Office. Also present (but not seen) is Brig. Gen. Donald P. Pettit, Commander, 45th Space Wing. After six Bumper launches at White Sands Proving Grounds, N.M., and a failed Bumper 7, a successful Bumper 8 lifted off July 24, 1950, from Complex 3/4 to conduct aerodynamic investigations around Mach 7 at relatively low altitudes. The kick-off event also inaugurated a student art contest to design a commemorative etching. The winning artwork will be permanently displayed on a 24-inch black granite square in the U.S. Space Walk Hall of Fame in Titusville, Fla
Buried bumper syndrome revisited: a rare but potentially fatal complication of PEG tube placement.
Biswas, Saptarshi; Dontukurthy, Sujana; Rosenzweig, Mathew G; Kothuru, Ravi; Abrol, Sunil
2014-01-01
Percutaneous endoscopic gastrostomy (PEG) has been used for providing enteral access to patients who require long-term enteral nutrition for years. Although generally considered safe, PEG tube placement can be associated with many immediate and delayed complications. Buried bumper syndrome (BBS) is one of the uncommon and late complications of percutaneous endoscopic gastrostomy (PEG) placement. It occurs when the internal bumper of the PEG tube erodes into the gastric wall and lodges itself between the gastric wall and skin. This can lead to a variety of additional complications such as wound infection, peritonitis, and necrotizing fasciitis. We present here a case of buried bumper syndrome which caused extensive necrosis of the anterior abdominal wall.
Wooten, Kimberly J; Smith, Philip N
2013-11-01
Chewing and mouthing behaviors exhibited by pet dogs are likely to lead to oral exposures to a variety of environmental chemicals. Products intended for chewing and mouthing uses include toys and training devices that are often made of plastics. The goal of the current study was to determine if a subset of phthalates and bisphenol A (BPA), endocrine disrupting chemicals commonly found in plastics, leach out of dog toys and training devices (bumpers) into synthetic canine saliva. In vitro assays were used to screen leachates for endocrine activity. Bumper leachates were dominated by di-2-ethylhexyl phthalate (DEHP) and BPA, with concentrations reaching low μg mL(-1) following short immersions in synthetic saliva. Simulated chewing of bumpers during immersion in synthetic saliva increased concentrations of phthalates and BPA as compared to new bumpers, while outdoor storage had variable effects on concentrations (increased DEHP; decreased BPA). Toys leached substantially lower concentrations of phthalates and BPA, with the exception of one toy which leached considerable amounts of diethyl phthalate. In vitro assays indicated anti-androgenic activity of bumper leachates, and estrogenic activity of both bumper and toy leachates. These results confirm that toys and training devices are potential sources of exposure to endocrine disrupting chemicals in pet dogs. Copyright © 2013 Elsevier Ltd. All rights reserved.
Strength Enhancement of Car Front Bumper for Slow Speed Impact by FEA Method as per IIHS Regulation
NASA Astrophysics Data System (ADS)
Sonawane, Chandrakant Rameshchandra; Shelar, Ajit Lavaji
2017-05-01
Low speed collisions happen significantly due to on road slow moving heavy traffic as well as during parking of vehicles. The bumpers are provided in front and back side of a vehicle has two main purposes: first is to absorb the energy generated during these kinds of slow speed impacts and secondly to protect the expensive parts like main engine parts, radiators and connected engine cooling mechanism, headlights, taillights, etc, by slowing down the vehicles. The problem often in various cars bumper is that they doesn't line-up vertically during low speed impact and leads to damage of various parts which are costly to repair. Many a times bumper design does not have sufficient capacity to absorb the energy generated during these impact. Guideline by International Institute Highway Safety (IIHS) regulation provides useful insight for such low speed impact study. In this paper, slow speed impact test were conducted as per IIHS regulation in three positions namely central impact, left hand corner impact and right hand corner impact. Parameters including bumper material, shape, thickness and impact condition are analyzed using fine element analysis (FEA) to enhance crashworthiness design in low speed impact. Then the vehicle front structure has been modified suitably. It has been observed that lining up the front metal bumper with suitable stiffness provides the best result which ultimately reduces the damage to the vehicle parts.
Ceremony at CCAS to kick off year-long celebration of 50 years of space launches
NASA Technical Reports Server (NTRS)
1999-01-01
At Cape Canaveral Air Station's (CCAS) Complex 3/4, officials held a ceremony kicking off a year-long series of events commemorating 50 years of launches from the Space Coast that began with the Bumper rockets. At right, Norris Gray, a Bumper Program veteran, unveils a street sign that will be used to mark the road leading to the launch complex from which Bumper was launched. Seen on the stage are, left to right, Lt. Col. Randall K. Horn (at the podium), Commander, CCAS; Congressman David Weldon, 15th Congressional District of the State of Florida; Lieutenant Governor of the State of Florida Frank T. Brogan; Center Director Roy D. Bridges; and Executive Director Edward F. Gormel, Joint Performance Management Office. Also present (but not seen) is Brig. Gen. Donald P. Pettit, Commander, 45th Space Wing. After six Bumper launches at White Sands Proving Grounds, N.M., and a failed Bumper 7, a successful Bumper 8 lifted off July 24, 1950, from Complex 3/4 to conduct aerodynamic investigations around Mach 7 at relatively low altitudes. The kick-off event also inaugurated a student art contest to design a commemorative etching. The winning artwork will be permanently displayed on a 24-inch black granite square in the U.S. space Walk hall of Fame in Titusville, Fla.
The Development and Design of a Prototype Ultra High Pressure P-19 Firefighting Vehicle
2007-02-03
the energizing affects of a delivery pressure 4 times (approximately 1200 psi) the magnitude of the standard system at the bumper turret nozzle...permanently extinguish a fire. The onboard CAF system is capable of 300 gpm delivery of foam at approximately 165 psi out of the bumper turret, and a...hand line flowing 45 gpm at approximately 165 psi also. The dry chemical system is designed to flow approximately 7 pps from the bumper turret, and 5
Severity of vehicle bumper location in vehicle-to-pedestrian impact accidents.
Matsui, Yasuhiro; Hitosugi, Masahito; Mizuno, Koji
2011-10-10
Pedestrian protection is one of the key topics for safety measures in traffic accidents all over the world. To analyze the relation between the collision site of the vehicle bumper and the severity of the lower extremity injuries, we performed biomechanical experiments. We compared the applied external force and the risks of subsequent injuries between the impact of the center and side positions of the front bumper. These comparisons were performed by practical impact tests with eight typical different types of cars which were typical of the current vehicle fleets. The tests were made using the TRL legform impactor which was a mechanical substitute of a pedestrian lower extremity. The TRL impactor is used all over the world for assessing the safety of car bumpers. It was found that the risks of lower extremity injuries in the impacts at the side positions, in front of the vehicle's side member, were significantly higher than those at the center. In the tests, we found that foam materials around the rigid front cross member had a significant effect on reducing the lower extremity injury risks and especially tibia fracture risk against vehicle bumper center collisions, but had little effect at the sides of the bumper over the vehicle's side members where the foam was thinner. We also found that the front shape of the vehicle affected the risk of ligaments injuries. According to these results, the information of impact locations of cars in vehicle-to-pedestrian traffic accidents is valuable for clinicians to diagnose patients with lower extremity injuries in traffic accidents and for forensic pathologists to analyze the accident reconstruction. Furthermore, the results suggest that testing of the bumper area in front of the main longitudinal beams should be included in the car safety legislation to require pedestrian safety. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Ceremony celebrates 50 years of rocket launches
NASA Technical Reports Server (NTRS)
2000-01-01
Ceremony celebrates 50 years of rocket launches PL00C-10364.12 At the 50th anniversary ceremony celebrating the first rocket launch from pad 3 on what is now Cape Canaveral Air Force Station, Norris Gray waves to the audience. Gray was part of the team who successfully launched the first rocket, known as Bumper 8. The ceremony was hosted by the Air Force Space & Missile Museum Foundation, Inc. , and included launch of a Bumper 8 model rocket, presentation of a Bumper Award to Florida Sen. George Kirkpatrick by the National Space Club; plus remarks by Sen. Kirkpatrick, KSC's Center Director Roy Bridges, and the Commander of the 45th Space Wing, Brig. Gen. Donald Pettit. Also attending the ceremony were other members of the original Bumper 8 team. A reception followed at Hangar C. Since 1950 there have been a total of 3,245 launches from Cape Canaveral.
Effect of lip bumpers on mandibular arch dimensions.
Hashish, Dena Ibrahim; Mostafa, Yehya Ahmed
2009-01-01
The aim of this systematic review was to examine the effects of lip bumper therapy on mandibular arch dimensions. A literature survey of PubMed, EMBASE, Cochrane Central, and Cochrane Database of Systematic Reviews (www.cochrane.org) was conducted from December 1968 to January 2007. Human studies, randomized clinical trials, prospective and retrospective studies, and studies discussing the effect of lip bumpers on the arch and teeth were included. Two reviewers independently selected and extracted the data. Of the 52 studies found in the search, only 1 met the inclusion criteria. The results showed increases in arch dimensions that included an increase in arch length. This was attributed to incisor proclination, distalization, and distal tipping of the molars. There was also an increase in the arch width seen in the intercanine and deciduous intermolar and premolar distances. The long-term stability of the effects of the lip bumper need to be elucidated.
NASA Astrophysics Data System (ADS)
Terumasa, Narukawa; Tomoki, Tsuge; Hiroshi, Yamamoto; Takahiro, Suzuki
2016-09-01
When autonomous unmanned vehicles are operated on sidewalks, the vehicles must have high safety standards such as avoiding injury when they come in contact with pedestrians. In this study, we established a design for preventing serious injury when such collisions occur. We designed an active bumper with a series elastic actuator, with the goal of avoiding serious injury to a pedestrian in a collision with a small unmanned vehicle. The series elastic actuator comprised an elastic element in series with a table driven by a ball screw and servo motor. The active bumper was used to control the contact force between a vehicle and a pedestrian. The optimal force for minimizing the deflection of the object of the collision was derived, and the actuator controlled to apply this optimal force. Numerical simulations showed that the active bumper was successful in improving the collision safety of small unmanned vehicles.
Code of Federal Regulations, 2010 CFR
2010-10-01
... OF TRANSPORTATION (CONTINUED) IMPORTATION OF VEHICLES AND EQUIPMENT SUBJECT TO FEDERAL SAFETY, BUMPER AND THEFT PREVENTION STANDARDS § 591.1 Scope. This part establishes procedures governing the importation of motor vehicles and motor vehicle equipment subject to the Federal motor vehicle safety, bumper...
DETAIL VIEW OF A HANDHELD BUMPER, USED TO AID IN ...
DETAIL VIEW OF A HANDHELD BUMPER, USED TO AID IN POSITIONING THE ORBITER DURING STACKING PROCEDURES - Cape Canaveral Air Force Station, Launch Complex 39, Vehicle Assembly Building, VAB Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL
77 FR 37836 - Petition Requesting Commission Action Regarding Crib Bumpers
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-25
... CONSUMER PRODUCT SAFETY COMMISSION 16 CFR Chapter II [Docket No. CPSC-2012-0034] Petition Requesting Commission Action Regarding Crib Bumpers AGENCY: U.S. Consumer Product Safety Commission. ACTION: Petition for rulemaking. SUMMARY: The U.S. Consumer Product Safety Commission (``Commission'') has received...
1999-08-24
At Cape Canaveral Air Station's Complex 3/4, officials held a ceremony, kicking off a year-long series of events commemorating 50 years of launches from the Space Coast, that began with the Bumper rockets. From left are Lieutenant Governor of the State of Florida Frank T. Brogan; Congressman David Weldon, 15th Congressional District of the State of Florida; Center Director Roy D. Bridges; and Executive Director Edward F. Gormel, Joint Performance Management Office. Also present (but not seen) is Brig. Gen. Donald P. Pettit, Commander, 45th Space Wing. After six Bumper launches at White Sands Proving Grounds, N.M., and a failed Bumper 7, a successful Bumper 8 lifted off July 24, 1950, from Complex 3/4 to conduct aerodynamic investigations around Mach 7 at relatively low altitudes. The kick-off event also inaugurated a student art contest to design a commemorative etching. The winning artwork will be permanently displayed on a 24-inch black granite square in the U.S. Space Walk Hall of Fame in Titusville, Fla
49 CFR 567.7 - Requirements for persons who alter certified vehicles.
Code of Federal Regulations, 2010 CFR
2010-10-01
... Federal motor vehicle safety, Bumper, and Theft Prevention standards, and (2) Assumes legal responsibility... Vehicle Safety, Bumper and Theft Prevention Standards affected by the alteration and in effect in (month... vehicles. 567.7 Section 567.7 Transportation Other Regulations Relating to Transportation (Continued...
49 CFR 571.224 - Standard No. 224; Rear impact protection.
Code of Federal Regulations, 2011 CFR
2011-10-01
... the vehicle is in motion. Nonstructural protrusions such as taillights, rubber bumpers, hinges and... deliver asphalt and other road building materials, in a controlled horizontal manner, into a lay down... protrusions such as taillights, hinges, rubber bumpers, and latches are excluded from the determination of the...
49 CFR 541.5 - Requirements for passenger motor vehicles.
Code of Federal Regulations, 2011 CFR
2011-10-01
...) Engine. (2) Transmission. (3) Right front fender. (4) Left front fender. (5) Hood. (6) Right front door. (7) Left front door. (8) Right rear door. (9) Left rear door. (10) Sliding or cargo door(s). (11) Front bumper. (12) Rear bumper. (13) Right rear quarter panel (passenger cars). (14) Left rear quarter...
49 CFR 541.5 - Requirements for passenger motor vehicles.
Code of Federal Regulations, 2010 CFR
2010-10-01
...) Engine. (2) Transmission. (3) Right front fender. (4) Left front fender. (5) Hood. (6) Right front door. (7) Left front door. (8) Right rear door. (9) Left rear door. (10) Sliding or cargo door(s). (11) Front bumper. (12) Rear bumper. (13) Right rear quarter panel (passenger cars). (14) Left rear quarter...
1999-08-24
At Cape Canaveral Air Station's (CCAS) Complex 3/4, officials held a ceremony kicking off a year-long series of events commemorating 50 years of launches from the Space Coast that began with the Bumper rockets. At left is artist Darlene Egli who designed the 50th anniversary logo next to her. On stage, from left to right, are Lt. Col. Randall K. Horn, Commander, CCAS; Brig. Gen. Donald P. Pettit, Commander, 45th Space Wing; Congressman David Weldon, 15th Congressional District of the State of Florida; Lieutenant Governor of the State of Florida Frank T. Brogan; Center Director Roy D. Bridges; and Executive Director Edward F. Gormel, Joint Performance Management Office. After six Bumper launches at White Sands Proving Grounds, N.M., and a failed Bumper 7, a successful Bumper 8 lifted off July 24, 1950, from Complex 3/4 to conduct aerodynamic investigations around Mach 7 at relatively low altitudes. The kick-off event also inaugurated a student art contest to design a commemorative etching. The winning artwork will be permanently displayed on a 24-inch black granite square in the U.S. Space Walk Hall of Fame in Titusville, Fla
Risk Assessment Update: Russian Segment
NASA Technical Reports Server (NTRS)
Christiansen, Eric; Lear, Dana; Hyde, James; Bjorkman, Michael; Hoffman, Kevin
2012-01-01
BUMPER-II version 1.95j source code was provided to RSC-E- and Khrunichev at January 2012 MMOD TIM in Moscow. MEMCxP and ORDEM 3.0 environments implemented as external data files. NASA provided a sample ORDEM 3.0 g."key" & "daf" environment file set for demonstration and benchmarking BUMPER -II v1.95j installation at the Jan-12 TIM. ORDEM 3.0 has been completed and is currently in beta testing. NASA will provide a preliminary set of ORDEM 3.0 ".key" & ".daf" environment files for the years 2012 through 2028. Bumper output files produced using the new ORDEM 3.0 data files are intended for internal use only, not for requirements verification. Output files will contain these words ORDEM FILE DESCRIPTION = PRELIMINARY VERSION: not for production. The projectile density term in many BUMPER-II ballistic limit equations will need to be updated. Cube demo scripts and output files delivered at the Jan-12 TIM have been updated for the new ORDEM 3.0 data files. Risk assessment results based on ORDEM 3.0 and MEM will be presented for the Russian Segment (RS) of ISS.
Ceremony at CCAS to kick off year-long celebration of 50 years of space launches
NASA Technical Reports Server (NTRS)
1999-01-01
At Cape Canaveral Air Station's Complex 3/4, officials held a ceremony, kicking off a year-long series of events commemorating 50 years of launches from the Space Coast, that began with the Bumper rockets. From left are Lieutenant Governor of the State of Florida Frank T. Brogan; Congressman David Weldon, 15th Congressional District of the State of Florida; Center Director Roy D. Bridges; and Executive Director Edward F. Gormel, Joint Performance Management Office. Also present (but not seen) is Brig. Gen. Donald P. Pettit, Commander, 45th Space Wing. After six Bumper launches at White Sands Proving Grounds, N.M., and a failed Bumper 7, a successful Bumper 8 lifted off July 24, 1950, from Complex 3/4 to conduct aerodynamic investigations around Mach 7 at relatively low altitudes. The kick-off event also inaugurated a student art contest to design a commemorative etching. The winning artwork will be permanently displayed on a 24-inch black granite square in the U.S. space Walk hall of Fame in Titusville, Fla.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-25
... Response Costs incurred at the Site. In exchange, the Settling Party will be granted a covenant not to sue... Costs Colorado Bumper Exchange Site, Pueblo, Pueblo County, CO AGENCY: Environmental Protection Agency... proposes to compromise a claim the United States has at this Site for Past Response Costs, as those terms...
Ceremony celebrates 50 years of rocket launches
NASA Technical Reports Server (NTRS)
2000-01-01
Ceremony celebrates 50 years of rocket launches PL00C-10364.16 At the 50th anniversary ceremony celebrating the first rocket launch from what is now Cape Canaveral Air Force Station, Brig. Gen. Donald Pettit addresses an audience that included members of the team who successfully launched the first rocket, known as Bumper 8. The ceremony was hosted by the Air Force Space & Missile Museum Foundation, Inc. , and included launch of a Bumper 8 model rocket, presentation of a Bumper Award to Florida Sen. George Kirkpatrick by the National Space Club; plus remarks by Sen. Kirkpatrick, KSC's Center Director Roy Bridges, and Pettit. A reception followed at Hangar C. Since 1950 there have been a total of 3,245 launches from Cape Canaveral.
Uncertainty Considerations for Ballistic Limit Equations
NASA Technical Reports Server (NTRS)
Schonberg, W. P.; Evans, H. J.; Williamsen, J. E; Boyer, R. L.; Nakayama, G. S.
2005-01-01
The overall risk for any spacecraft system is typically determined using a Probabilistic Risk Assessment (PRA). A PRA determines the overall risk associated with a particular mission by factoring in all known risks to the spacecraft during its mission. The threat to mission and human life posed by the micro-meteoroid and orbital debris (MMOD) environment is one of the risks. NASA uses the BUMPER II program to provide point estimate predictions of MMOD risk for the Space Shuttle and the ISS. However, BUMPER II does not provide uncertainty bounds or confidence intervals for its predictions. In this paper, we present possible approaches through which uncertainty bounds can be developed for the various damage prediction and ballistic limit equations encoded within the Shuttle and Station versions of BUMPER II.
Pedestrian Injuries By Source: Serious and Disabling Injuries in US and European Cases
Mallory, Ann; Fredriksson, Rikard; Rosén, Erik; Donnelly, Bruce
2012-01-01
US and European pedestrian crash cases were analyzed to determine frequency of injury by body region and by the vehicle component identified as the injury source. US pedestrian data was drawn from the Pedestrian Crash Data Study (PCDS). European pedestrian data was drawn from the German In-Depth Accident Study (GIDAS). Results were analyzed in terms of both serious injury (AIS 3+) and disabling injury estimated with the Functional Capacity Index (FCI). The results are presented in parallel for a more complete international perspective on injuries and injury sources. Lower extremity injury from bumper impact and head&face injury from windshield impact were the most frequent combinations for both serious and disabling injuries. Serious lower extremity injuries from bumper contact occurred in 43% of seriously injured pedestrian cases in US PCDS data and 35% of European GIDAS cases. Lower-extremity bumper injuries also account for more than 20% of disability in both datasets. Serious head &face injuries from windshield contact occur in 27% of PCDS and 15% of GIDAS serious injury cases. While bumper impacts primarily result in lower extremity injury and windshield impacts are most often associated with head & face injuries, the hood and hood leading edge are responsible for serious and disabling injuries to a number of different body regions. Therefore, while it is appropriate to focus on lower extremity injury when studying bumper performance and on head injury risk when studying windshield impact, pedestrian performance of other components may require better understanding of injury risk for multiple body regions. PMID:23169112
ERIC Educational Resources Information Center
Potter, Lee Ann
2004-01-01
During the season of political campaigns scores of bumper stickers, posters, and other items with slogans supporting one candidate or another suddenly appear and quickly multiply around neighborhoods and towns, with stickers plastered on cars, and posters hanging in windows, or posted in front yards. From George Washington to George W. Bush,…
1999-08-24
At Cape Canaveral Air Station's (CCAS) Complex 3/4, officials held a ceremony kicking off a year-long series of events commemorating 50 years of launches from the Space Coast that began with the Bumper rockets. At left is Jim Thompson, who is with CCAS. Unveiling the 50th anniversary logo at left is the artist Darlene Egli. On stage, from left to right, are Lt. Col. Randall K. Horn, Commander, CCAS; Congressman David Weldon, 15th Congressional District of the State of Florida; Lieutenant Governor of the State of Florida Frank T. Brogan; Center Director Roy D. Bridges; and Executive Director Edward F. Gormel, Joint Performance Management Office. Also present (but not seen) is Brig. Gen. Donald P. Pettit, Commander, 45th Space Wing. After six Bumper launches at White Sands Proving Grounds, N.M., and a failed Bumper 7, a successful Bumper 8 lifted off July 24, 1950, from Complex 3/4 to conduct aerodynamic investigations around Mach 7 at relatively low altitudes. The kick-off event also inaugurated a student art contest to design a commemorative etching. The winning artwork will be permanently displayed on a 24-inch black granite square in the U.S. space Walk Hall of Fame in Titusville, Fla
Li, Guibing; Lyons, Mathew; Wang, Bingyu; Yang, Jikuang; Otte, Dietmar; Simms, Ciaran
2017-04-01
Quantified relationships between passenger car front shape and pedestrian injury risk derived from accident data are sparse, especially considering the significant recent changes in car front design. The purpose of this paper is therefore to investigate the detailed effects of passenger car front shape on injury risk to a pedestrian's head, thorax, pelvis and leg in the event of a vehicle pedestrian impact. Firstly, an accident sample of 594 pedestrian cases captured during 2000-2015 from the German In-Depth Accident Study (GIDAS) database was employed. Multicollinearity diagnostic statistics were then used to detect multicollinearity between the predictors. Following this, logistic regression was applied to quantify the effects of passenger car front shape on injury risks while controlling for impact speed and pedestrian age. Results indicate that the bumper lower depth (BLD), bumper lower height (BLH), bumper upper height (BUH) and normalised bumper lower/upper height (NBLH/NBUH) are statistically significant for AIS2+ leg injury risk. The normalised bonnet leading edge height (NBLEH) has a statistically significant influence on AIS2+ femur/pelvis injury occurrence. The passenger car front shape did not show statistical significance for AIS3+ thorax and head injuries. The impact speed and pedestrian age are generally significant factors influencing AIS2+ leg and pelvis injuries, and AIS3+ thorax and head injuries. However, when head impacts are fixed on the central windscreen region both pedestrian age and impact speed are not statistically significant for AIS3+ head injury. For quantified effects, when controlling for speed, age and BUH, an average 7% and 6% increase in AIS2+ leg injury odds was observed for every 1cm increase in BLD and BLH respectively; 1cm increase in BUH results in a 7% decrease in AIS2+ leg injury odds when the BLD or BLH are fixed respectively (again controlling for impact speed and pedestrian age); the average AIS2+ femur/pelvis injury odds increase by 74% for a 10% increase in NBLEH. These findings suggest that passenger car bumpers should support the lower leg with a low and flat lower bumper and even contact up to the femur area with a high upper bumper which extends above the knee to protect the pedestrian's leg. A low passenger car bonnet leading edge helps to reduce femur/pelvis injury risk. The passenger car front shape parameters are less influential than impact speed and pedestrian age for pedestrian injury risk. Copyright © 2017 Elsevier Ltd. All rights reserved.
Technology: Computer Applications for Young Users--BumperCar and KidPix
ERIC Educational Resources Information Center
Van Horn, Royal
2004-01-01
There is a lot of software available for young children, but there are not many applications designed especially for them. This situation may be about to change with the release of BumperCar and a new version of KidPix, both of which recently earned awards from MacWorld magazine. In this article, the author describes this new software and how it…
Unstructured Facility Navigation by Applying the NIST 4D/RCS Architecture
2006-07-01
control, and the planner); wire- less data and emergency stop radios; GPS receiver; inertial navigation unit; dual stereo cameras; infrared sensors...current Actuators Wheel motors, camera controls Scale & filter signals status commands commands commands GPS Antenna Dual stereo cameras...used in the sensory processing module include the two pairs of stereo color cameras, the physical bumper and infrared bumper sensors, the motor
Raucci, Gaetana; Pachêco-Pereira, Camila; Elyasi, Maryam; d'Apuzzo, Fabrizia; Flores-Mir, Carlos; Perillo, Letizia
2017-03-01
To identify which dental and/or cephalometric variables were predictors of postretention mandibular dental arch stability in patients who underwent treatment with transpalatal arch and lip bumper during mixed dentition followed by full fixed appliances in the permanent dentition. Thirty-one patients were divided into stable and relapse groups based on the postretention presence or absence of relapse. Intercuspid, interpremolar, and intermolar widths; arch length and perimeter; crowding; and lower incisor proclination were evaluated before treatment (T0), after lip bumper treatment (T1), after fixed appliance treatment (T2), and a minimum of 3 years after removal of the full fixed appliance (T3). Logistic regression analyses were performed to evaluate the effect of changes between T0 and T1, as predictive variables, on the occurrence of relapse at T3. The model explained 53.5 % of the variance in treatment stability and correctly classified 80.6 % of the sample. Of the seven prediction variables, intermolar and interpremolar changes between T0 and T1 (P = .024 and P = .034, respectively) were statistically significant. For every millimeter of increase in intermolar and interpremolar widths there was a 1.52 and 2.70 times increase, respectively, in the odds of having stability. There was also weak evidence for the effect of sex (P = .047). The best predictors of an average 4-year postretention mandibular dental arch stability after treatment with a lip bumper followed by full fixed appliances were intermolar and interpremolar width increases during lip bumper therapy. The amount of relapse in this crowding could be considered clinically irrelevant.
NASA Technical Reports Server (NTRS)
Rule, William Keith
1991-01-01
A computer program called BALLIST that is intended to be a design tool for engineers is described. BALLlST empirically predicts the bumper thickness required to prevent perforation of the Space Station pressure wall by a projectile (such as orbital debris) as a function of the projectile's velocity. 'Ballistic' limit curves (bumper thickness vs. projectile velocity) are calculated and are displayed on the screen as well as being stored in an ASCII file. A Whipple style of spacecraft wall configuration is assumed. The predictions are based on a database of impact test results. NASA/Marshall Space Flight Center currently has the capability to generate such test results. Numerical simulation results of impact conditions that can not be tested (high velocities or large particles) can also be used for predictions.
Ceremony celebrates 50 years of rocket launches
NASA Technical Reports Server (NTRS)
2000-01-01
Ceremony celebrates 50 years of rocket launches PL00C-10364.21 At the 50th anniversary ceremony celebrating the first rocket launch from pad 3 on what is now Cape Canaveral Air Force Station, KSC's Center Director Roy Bridges Jr. addresses an audience that included members of the team who successfully launched the first rocket, known as Bumper 8. The original launch occurred July 24, 1950. The anniversary ceremony was hosted by the Air Force Space & Missile Museum Foundation, Inc., and included launch of a Bumper 8 model rocket, presentation of a Bumper Award to Florida Sen. George Kirkpatrick by the National Space Club; plus remarks by Sen. Kirkpatrick, Bridges, and the Commander of the 45th Space Wing, Brig. Gen. Donald Pettit. A reception followed at Hangar C. Since 1950 there have been a total of 3,245 launches from Cape Canaveral.
Mo, Fuhao; Zhao, Siqi; Yu, Chuanhui; Duan, Shuyong
2018-01-01
The car front bumper system needs to meet the requirements of both pedestrian safety and low-speed impact which are somewhat contradicting. This study aims to design a new kind of modular self-adaptive energy absorber of the front bumper system which can balance the two performances. The X-shaped energy-absorbing structure was proposed which can enhance the energy absorption capacity during impact by changing its deformation mode based on the amount of external collision energy. Then, finite element simulations with a realistic vehicle bumper system are performed to demonstrate its crashworthiness in comparison with the traditional foam energy absorber, which presents a significant improvement of the two performances. Furthermore, the structural parameters of the X-shaped energy-absorbing structure including thickness (t u), side arc radius (R), and clamping boost beam thickness (t b) are analyzed using a full factorial method, and a multiobjective optimization is implemented regarding evaluation indexes of both pedestrian safety and low-speed impact. The optimal parameters are then verified, and the feasibility of the optimal results is confirmed. In conclusion, the new X-shaped energy absorber can meet both pedestrian safety and low-speed impact requirements well by altering the main deformation modes according to different impact energy levels. PMID:29581728
Mo, Fuhao; Zhao, Siqi; Yu, Chuanhui; Xiao, Zhi; Duan, Shuyong
2018-01-01
The car front bumper system needs to meet the requirements of both pedestrian safety and low-speed impact which are somewhat contradicting. This study aims to design a new kind of modular self-adaptive energy absorber of the front bumper system which can balance the two performances. The X-shaped energy-absorbing structure was proposed which can enhance the energy absorption capacity during impact by changing its deformation mode based on the amount of external collision energy. Then, finite element simulations with a realistic vehicle bumper system are performed to demonstrate its crashworthiness in comparison with the traditional foam energy absorber, which presents a significant improvement of the two performances. Furthermore, the structural parameters of the X-shaped energy-absorbing structure including thickness ( t u ), side arc radius ( R ), and clamping boost beam thickness ( t b ) are analyzed using a full factorial method, and a multiobjective optimization is implemented regarding evaluation indexes of both pedestrian safety and low-speed impact. The optimal parameters are then verified, and the feasibility of the optimal results is confirmed. In conclusion, the new X-shaped energy absorber can meet both pedestrian safety and low-speed impact requirements well by altering the main deformation modes according to different impact energy levels.
LCA and design for environment (DFE) -- Application to the automotive industry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bensahel, J.F.; Teulon, H.
End of life of large plastic parts is a major issue for the automotive industry, whereas metal parts are easily recycled. Ecobilan is carrying out a study on plastic bumpers, for the French car manufacturer Peugeot SA. This study aims at estimating the environmental impacts of three alternative treatments for plastic bumpers at the end of life of the car: (1 ) crushing and shredding with the whole automobile, screening of the metallic and mineral part, and incineration of the automobile shredder residue, (2) dismantling and separate incineration of bumpers, (3) dismantling and recycling of bumpers, as new plastic partsmore » for the automobile industry. Systems boundaries are defined so as to include into the systems only the steps which makes difference between the three options. The long term stake of the study is to include environmental data in the design of the car, along with technical and economic elements, that is to say to Design For Environment. The objective is to find economic, technical and environmental optimum for complex products, that makes sense on the whole life cycle of the product. Peugeot SA agrees to publish some results, which will be available by May 1995. These results will mix both environmental and economic analysis.« less
NASA Astrophysics Data System (ADS)
Syam, Bustami; Sebayang, Alexander; Sebayang, Septian; Muttaqin, Maraghi; Darmadi, Harry; Basuki, WS; Sabri, M.; Abda, S.
2018-03-01
Open channel conduit is designed and produced with the aims to reduce excess water, whether from rain, seepage, or excess irrigation water in an area. It is also included in one of the important components of urban infrastructure in tackling the problem of flooding and waterlogging. On the roadway, e.g. housing complex the open channel conduits should function the same, however conduit covers are needed. The covers should be also designed to function as parking bumper. This paper discusses the design and production of the stoppers using our newly invented materials; the stoppers are structurally tested under static, dynamic, and bump test. Response of the conduit cover are found from structural analysis using finite element software ANSYS MECHANICAL version 17.5. Two types of stoppers are introduced: flat and curvy configuration. It was obtained that both types are suitable for open channel conduit cover and parking bumper.
Bumper and grille airbags concept for enhanced vehicle compatibility in side impact: phase II.
Barbat, Saeed; Li, Xiaowei; Prasad, Priya
2013-01-01
Fundamental physics and numerous field studies have shown a higher injury and fatality risk for occupants in smaller and lighter vehicles when struck by heavier, taller and higher vehicles. The consensus is that the significant parameters influencing compatibility in front-to-side crashes are geometric interaction, vehicle stiffness, and vehicle mass. The objective of this research is to develop a concept of deployable bumper and grille airbags for improved vehicle compatibility in side impact. The external airbags, deployed upon signals from sensors, may help mitigate the effect of weight, geometry and stiffness differences and reduce side intrusions. However, a highly reliable pre-crash sensing system is required to enable the reliable deployment, which is currently not technologically feasible. Analytical and numerical methods and hardware testing were used to help develop the deployable external airbags concept. Various Finite Element (FE) models at different stages were developed and an extensive number of iterations were conducted to help optimize airbag and inflator parameters to achieve desired targets. The concept development was executed and validated in two phases. This paper covers Phase II ONLY, which includes: (1) Re-design of the airbag geometry, pressure, and deployment strategies; (2) Further validation using a Via sled test of a 48 kph perpendicular side impact of an SUV-type impactor against a stationary car with US-SID-H3 crash dummy in the struck side; (3) Design of the reaction surface necessary for the bumper airbag functionality. The concept was demonstrated through live deployment of external airbags with a reaction surface in a full-scale perpendicular side impact of an SUV against a stationary passenger car at 48 kph. This research investigated only the concept of the inflatable devices since pre-crash sensing development was beyond the scope of this research. The concept design parameters of the bumper and grille airbags are presented in this paper. Full vehicle-to-vehicle crash test results, Via sled test, and simulation results are also presented. Head peak acceleration, Head Injury Criteria (HIC), Thoracic Trauma Index (TTI), and Pelvic acceleration for the SID-H3 dummy and structural intrusion profiles were used as performance metrics for the bumper and grille airbags. Results obtained from the Via sled tests and the full vehicle-to-vehicle tests with bumper and grille airbags were compared to those of baseline test results with no external airbags.
BUMPER v1.0: a Bayesian user-friendly model for palaeo-environmental reconstruction
NASA Astrophysics Data System (ADS)
Holden, Philip B.; Birks, H. John B.; Brooks, Stephen J.; Bush, Mark B.; Hwang, Grace M.; Matthews-Bird, Frazer; Valencia, Bryan G.; van Woesik, Robert
2017-02-01
We describe the Bayesian user-friendly model for palaeo-environmental reconstruction (BUMPER), a Bayesian transfer function for inferring past climate and other environmental variables from microfossil assemblages. BUMPER is fully self-calibrating, straightforward to apply, and computationally fast, requiring ˜ 2 s to build a 100-taxon model from a 100-site training set on a standard personal computer. We apply the model's probabilistic framework to generate thousands of artificial training sets under ideal assumptions. We then use these to demonstrate the sensitivity of reconstructions to the characteristics of the training set, considering assemblage richness, taxon tolerances, and the number of training sites. We find that a useful guideline for the size of a training set is to provide, on average, at least 10 samples of each taxon. We demonstrate general applicability to real data, considering three different organism types (chironomids, diatoms, pollen) and different reconstructed variables. An identically configured model is used in each application, the only change being the input files that provide the training-set environment and taxon-count data. The performance of BUMPER is shown to be comparable with weighted average partial least squares (WAPLS) in each case. Additional artificial datasets are constructed with similar characteristics to the real data, and these are used to explore the reasons for the differing performances of the different training sets.
Micrometeoroid and Orbital Debris Threat Assessment: Mars Sample Return Earth Entry Vehicle
NASA Technical Reports Server (NTRS)
Christiansen, Eric L.; Hyde, James L.; Bjorkman, Michael D.; Hoffman, Kevin D.; Lear, Dana M.; Prior, Thomas G.
2011-01-01
This report provides results of a Micrometeoroid and Orbital Debris (MMOD) risk assessment of the Mars Sample Return Earth Entry Vehicle (MSR EEV). The assessment was performed using standard risk assessment methodology illustrated in Figure 1-1. Central to the process is the Bumper risk assessment code (Figure 1-2), which calculates the critical penetration risk based on geometry, shielding configurations and flight parameters. The assessment process begins by building a finite element model (FEM) of the spacecraft, which defines the size and shape of the spacecraft as well as the locations of the various shielding configurations. This model is built using the NX I-deas software package from Siemens PLM Software. The FEM is constructed using triangular and quadrilateral elements that define the outer shell of the spacecraft. Bumper-II uses the model file to determine the geometry of the spacecraft for the analysis. The next step of the process is to identify the ballistic limit characteristics for the various shield types. These ballistic limits define the critical size particle that will penetrate a shield at a given impact angle and impact velocity. When the finite element model is built, each individual element is assigned a property identifier (PID) to act as an index for its shielding properties. Using the ballistic limit equations (BLEs) built into the Bumper-II code, the shield characteristics are defined for each and every PID in the model. The final stage of the analysis is to determine the probability of no penetration (PNP) on the spacecraft. This is done using the micrometeoroid and orbital debris environment definitions that are built into the Bumper-II code. These engineering models take into account orbit inclination, altitude, attitude and analysis date in order to predict an impacting particle flux on the spacecraft. Using the geometry and shielding characteristics previously defined for the spacecraft and combining that information with the environment model calculations, the Bumper-II code calculates a probability of no penetration for the spacecraft.
NASA Technical Reports Server (NTRS)
Cour-Palais, Burton G.; Avans, Sherman L.
1988-01-01
The damage to spacecraft caused by debris and design of the Space Station to minimize damage from debris are discussed. Although current estimates of the debris environment show that fragments bigger than 2 cm are not likely to hit the Space Station, orbital debris from about 0.5 mm to 2 cm will pose a hazard, especially on brittle surfaces, such as glass. Spacesuits are being designed to reduce debris caused dangers to astronauts during EVA. About 5 cm of high-strength aluminum are needed to prevent penetration by a 1 cm piece of aluminum with a mass near 1.5 g colliding at 10 km/sec. Because aluminum bumpers have the drawback of metallic debris ejected outward after a hypervelocity collision, the use of nonmetallic materials for bumpers is being studied. Methods of reducing the weight and volume of the shield for the Space Station are also being researched. A space station habitation module using bumpers has a 99.6 percent chance of avoiding penetration during its lifetime.
Optimisation study of a vehicle bumper subsystem with fuzzy parameters
NASA Astrophysics Data System (ADS)
Farkas, L.; Moens, D.; Donders, S.; Vandepitte, D.
2012-10-01
This paper deals with the design and optimisation for crashworthiness of a vehicle bumper subsystem, which is a key scenario for vehicle component design. The automotive manufacturers and suppliers have to find optimal design solutions for such subsystems that comply with the conflicting requirements of the regulatory bodies regarding functional performance (safety and repairability) and regarding the environmental impact (mass). For the bumper design challenge, an integrated methodology for multi-attribute design engineering of mechanical structures is set up. The integrated process captures the various tasks that are usually performed manually, this way facilitating the automated design iterations for optimisation. Subsequently, an optimisation process is applied that takes the effect of parametric uncertainties into account, such that the system level of failure possibility is acceptable. This optimisation process is referred to as possibility-based design optimisation and integrates the fuzzy FE analysis applied for the uncertainty treatment in crash simulations. This process is the counterpart of the reliability-based design optimisation used in a probabilistic context with statistically defined parameters (variabilities).
NASA Technical Reports Server (NTRS)
Rule, W. K.; Giridharan, V.
1991-01-01
A family of user-friendly, DOS PC based, Microsoft BASIC programs written to provide spacecraft designers with empirical predictions of space debris damage to orbiting spacecraft are described. Spacecraft wall temperatures and condensate formation is also predicted. The spacecraft wall configuration is assumed to consist of multilayered insulation (MLI) placed between a Whipple style bumper and the pressure wall. Impact damage predictions are based on data sets of experimental results obtained from simulating debris impacts on spacecraft using light gas guns on earth. A module of the program facilitates the creation of the database of experimental results that is used by the damage prediction modules to predict damage to the bumper, the MLI, and the pressure wall. A finite difference technique is used to predict temperature distributions in the pressure wall, the MLI, and the bumper. Condensate layer thickness is predicted for the case where the pressure wall temperature drops below the dew point temperature of the spacecraft atmosphere.
Matthews, Les; Fortier, Normand
2013-01-01
The present study was designed to investigate body position changes resulting from wearing a Rematee Bumper Belt (Rematee, Canada) during sleep. The majority of obstructive sleep apnea (OSA) patients will experience up to two times as many apneas and hypopneas while supine relative to lateral or prone body positions during sleep. It has been suggested that a positional therapy device could reduce the number of apneas and hypopneas in such patients. The present study was conducted to determine whether the Rematee Bumper Belt positional therapy device could prevent healthy subjects from sleeping in the supine position. Test subjects wore the belt for one to two nights. Each belt was equipped with an accelerometer that was used to measure the orientation of the belt relative to the horizontal plane. The results suggest that the belt creates an exclusion zone approximately 80° wide centred near the supine orientation, where subjects are effectively prevented to enter. Results of the present preliminary study suggests that the Rematee Bumper Belt positional therapy device is effective at limiting healthy subjects from sleeping in a supine position. The device appears to be most effective between 150° and 230°. A device with this capability may provide an inexpensive and potentially effective alternative treatment option for patients with OSA. This device has the capacity for reducing snoring and the apnea-hypopnea index in individuals with positional OSA. PMID:26078596
Projectile Shape Effects Analysis for Space Debris Impact
NASA Astrophysics Data System (ADS)
Shiraki, Kuniaki; Yamamoto, Tetsuya; Kamiya, Takeshi
2002-01-01
(JEM IST), has a manned pressurized module used as a research laboratory on orbit and planned to be attached to the International Space Station (ISS). Protection system from Micrometeoroids and orbital debris (MM/OD) is very important for crew safety aboard the ISS. We have to design a module with shields attached to the outside of the pressurized wall so that JEM can be protected when debris of diameter less than 20mm impact on the JEM wall. In this case, the ISS design requirement for space debris protection system is specified as the Probability of No Penetration (PNP). The PNP allocation for the JEM is 0.9738 for ten years, which is reallocated as 0.9814 for the Pressurized Module (PM) and 0.9922 for the Experiment Logistics Module-Pressurized Section (ELM-PS). The PNP is calculated with Bumper code provided by NASA with the following data inputs to the calculation. (1) JEM structural model (2) Ballistic Limit Curve (BLC) of shields pressure wall (3) Environmental conditions: Analysis type, debris distribution, debris model, debris density, Solar single aluminum plate bumper (1.27mm thickness). The other is a Stuffed Whipple shield with its second bumper composed of an aluminum mesh, three layers of Nextel AF62 ceramic fabric, and four layers of Kevlar 710 fabric with thermal isolation material Multilayer Insulation (MLI) in the bottom. The second bumper of Stuffed Whipple shields is located at the middle between the first bumper and the 4.8 mm-thick pressurized wall. with Two-Stage Light Gas Gun (TSLGG) tests and hydro code simulation already. The remaining subject is the verification of JEM debris protection shields for velocities ranging from 7 to 15 km/sec. We conducted Conical Shaped Charge (CSC) tests that enable hypervelocity impact tests for the debris velocity range above 10 km/sec as well as hydro code simulation. because of the jet generation mechanism. It is therefore necessary to analyze and compensate the results for a solid aluminum sphere, which is the design requirement.
NASA Technical Reports Server (NTRS)
Hoerz, Friedrich; Cintala, Mark J.; Bernhard, Ronald P.; Cardenas, Frank; Davidson, William; Haynes, Gerald; See, Thomas H.; Winkler, Jerry; Gray, Barry
1993-01-01
The utility of multiple-mesh targets as potential lightweight shields to protect spacecraft in low-Earth orbit against collisional damage is explored. Earlier studies revealed that single meshes comminute hypervelocity impactors with efficiencies comparable to contiguous targets. Multiple interaction of projectile fragments with any number of meshes should lead to increased comminution, deceleration, and dispersion of the projectile, such that all debris exiting the mesh stack possesses low specific energies (ergs/sq cm) that would readily be tolerated by many flight systems. The study is conceptually exploring the sensitivity of major variables such as impact velocity, the specific areal mass (g/sq cm) of the total mesh stack (SM), and the separation distance (S) between individual meshes. Most experiments employed five or ten meshes with total SM typically less than 0.5 the specific mass of the impactor, and silicate glass impactors rather than metal projectiles. While projectile comminution increases with increasing impact velocity due to progressively higher shock stresses, encounters with multiple-meshes at low velocity (1-2 km/s) already lead to significant disruption of the glass impactors, with the resulting fragments being additionally decelerated and dispersed by subsequent meshes, and, unlike most contiguous single-plate bumpers, leading to respectable performance at low velocity. Total specific bumper mass must be the subject of careful trade-off studies; relatively massive bumpers will generate too much debris being dislodged from the bumper itself, while exceptionally lightweight designs will not cause sufficient comminution, deceleration, or dispersion of the impactor. Separation distance was found to be a crucial design parameter, as it controls the dispersion of the fragment cloud. Substantial mass savings could result if maximum separation distances were employed. The total mass of debris dislodged by multiple-mesh stacks is modestly smaller than that of single, contiguous-membrane shields. The cumulative surface area of all penetration holes in multiple mesh stacks is an order of magnitude smaller than that in analog multiple-foil shields, suggesting good long-term performance of the mesh designs. Due to different experimental conditions, direct and quantitative comparison with other lightweight shields is not possible at present.
Space station integrated wall design and penetration damage control
NASA Technical Reports Server (NTRS)
Coronado, A. R.; Gibbins, M. N.; Wright, M. A.; Stern, P. H.
1987-01-01
The analysis code BUMPER executes a numerical solution to the problem of calculating the probability of no penetration (PNP) of a spacecraft subject to man-made orbital debris or meteoroid impact. The codes were developed on a DEC VAX 11/780 computer that uses the Virtual Memory System (VMS) operating system, which is written in FORTRAN 77 with no VAX extensions. To help illustrate the steps involved, a single sample analysis is performed. The example used is the space station reference configuration. The finite element model (FEM) of this configuration is relatively complex but demonstrates many BUMPER features. The computer tools and guidelines are described for constructing a FEM for the space station under consideration. The methods used to analyze the sensitivity of PNP to variations in design, are described. Ways are suggested for developing contour plots of the sensitivity study data. Additional BUMPER analysis examples are provided, including FEMs, command inputs, and data outputs. The mathematical theory used as the basis for the code is described, and illustrates the data flow within the analysis.
Design mechanic generator under speed bumper to support electricity recourse for urban traffic light
NASA Astrophysics Data System (ADS)
Sabri, M.; Lauzuardy, Jason; Syam, Bustami
2018-03-01
The electrical energy needs for the traffic lights in some cities of developing countries cannot be achieved continuously due to limited capacity and interruption of electricity distribution, the main power plant. This issues can lead to congestion at the crossroads. To overcome the problem of street chaos due to power failure, we can cultivate to provide electrical energy from other sources such as using the bumper to generate kinetic energy, which can be converted into electrical energy. This study designed a generator mechanic that will be mounted on the bumper construction to generate electricity for the purposes of traffic lights at the crossroads. The Mechanical generator is composed of springs, levers, sprockets, chains, flywheel and customize power generator. Through the rotation of the flywheel, we can earned 9 Volt DC voltage and electrical current of 5.89 Ampere. This achievement can be used to charge the accumulator which can be used to power the traffic lights, and to charge the accumulator capacity of 6 Ah, the generator works in the charging time for 1.01 hours.
Do head-restraints protect the neck from whiplash injuries?
Morris, F
1989-01-01
Over an 11-month period a study was made of all patients presenting to an accident and emergency department who had sustained whiplash as a result of rear-bumper impacts. The patients were analysed with respect to the presence of head-restraints in their vehicles. A significant increase in the incidence of whiplash was found in patients whose vehicles did not have head-restraints fitted. Legislation requiring all passenger cars to have head-restraints fitted as standard would have a major impact in reducing the number of whiplash injuries sustained in rear bumper impacts. PMID:2712983
NASA Technical Reports Server (NTRS)
Fitzgerald, Howard J.; Yano, Hajime
1995-01-01
Four of the eight available double layer microparticle capture cells, flown as the experiment A0023 on the trailing (West) face of LDEF, have been extensively studied. An investigation of the chemistry of impactors has been made using SEM/EDX techniques and the effectiveness of the capture cells as bumper shields has also been examined. Studies of these capture cells gave positive EDX results, with 53 percent of impact sites indicating the presence of some chemical residues, the predominant residue identified as being silicon in varying quantities.
A Magnetic Bumper-Tether System Using ZFC Y123
NASA Technical Reports Server (NTRS)
Weinstein, Roy; Parks, Drew; Sawh, Ravi-Persad; Obot, Victor; Liu, Jianxiong; Arndt, G. D.
1996-01-01
We consider the use of magnetic forces in a bumper system, to soften docking procedures. We investigate a system which exhibits no magnetic field except during the docking process, which, if desired, can automatically tether two craft together, and which provides lateral stability during docking. A system composed of zero field cooled Y(1.7)Ba2Cu3O(7-delta) (Y123) tiles and electromagnets is proposed. The Y123 high temperature superconductor (HTS) is mounted on one craft, and the electromagnet on the other. Results of small prototype laboratory experiments are reported. The electromagnet has, for convenience, been replaced by a permanent SmCo ferromagnet in these measurements. When the two craft approach, a mirror image of the ferromagnet is induced in the Y123, and a repulsive bumper force, F(sub B), results. F(sub B) is velocity dependent, and increases with v. For presently available HTS materials, bumper pressure of approx. 3.7 N/cm(exp 2) is achieved using SmCo. This extrapolates to approx. 18 N/cm(exp 2) for an electromagnet, or a force of up to 20 tons for a 1 m(exp 2) system. After reaching a minimum distance of approach, the two colliding craft begin to separate. However, the consequent change of SmCo magnetic field at the Y123 results in a reversal of current in the Y123 so that the Y123 is attractive to the SmCo. The attractive (tether) force, F(sub T), is a function of R = B(sub Fe)/B(sub t, max), where B(sub Fe) is the field at the surface of the ferromagnet, and B(sub t, max) is the maximum trapped field of the Y123, i.e., the trapped field in the so-called critical state. For R greater than or equal to 2, F(sub T) saturates at a value comparable to F(sub B). For a range of initial approach velocities the two craft are tethered following the bumper sequence. Most of the kinetic energy of the collision is first converted to magnetic field energy in the Y123, and then into heat via the creep mechanism. About 15% of the work done against magnetic forces during collision remains stored as magnetic energy after 1 hour. Experiments have also been conducted on the spatial range of the bumper force for arrays of HTS tiles. For a single HTS tile approx. 2 cm in diameter, the range of F(sub B) is approx. l cm. For a l m(exp 2) array the range of F(sub B) will be circa 50 cm.
Otte, D.; Haasper, C.
2007-01-01
This study deals with the analysis of lower leg fractures in pedestrians and bicyclists after collisions with passenger cars and examines to what extent the shape and location of the factures in the lower leg changed, following alterations in the shape of bumpers. It can be assumed that that the bumpers changed in shape and effective impact height, not least due to the realization of the developments of vehicle safety tests as in the context of the European Union Directive 2003/102/EC on pedestrian protection. In addition, consumer protection tests, EuroNCAP, accomplished a change of the injury situation. All of these are mainly focused on pedestrian protection measurements but adopt the bicyclists also in their goal. For the study, traffic accidents from GIDAS (German in-Depth-Accident Study) were selected, which had been documented in the years 1995 to 2004 by scientific teams in Hannover and Dresden (Germany) and for which there is detailed information regarding injury patterns and collision speeds. The accident documentations can be regarded as representative and constitute a random sample with statistic weighing of the data. Altogether 143 cases of lower leg fractures (Tibia/Fibula) with x-rays of pedestrians and 79 cases of bicyclists were differentiated according to new and old vehicles (year of manufacture before/after 1995). The bumper shapes were divided into classical types (protruding pronouncedly/protruding integrated /integrated rounded). Besides the injuries to the lower leg, those to thighs and feet were also regarded, and the injury conditions involving the head and trunk were included in the kinematic analytics. PMID:18184485
Otte, D; Haasper, C
2007-01-01
This study deals with the analysis of lower leg fractures in pedestrians and bicyclists after collisions with passenger cars and examines to what extent the shape and location of the fractures in the lower leg changed, following alterations in the shape of bumpers. It can be assumed that that the bumpers changed in shape and effective impact height, not least due to the realization of the developments of vehicle safety tests as in the context of the European Union Directive 2003/102/EC on pedestrian protection. In addition, consumer protection tests, EuroNCAP, accomplished a change of the injury situation. All of these are mainly focused on pedestrian protection measurements but adopt the bicyclists also in their goal. For the study, traffic accidents from GIDAS (German in-Depth-Accident Study) were selected, which had been documented in the years 1995 to 2004 by scientific teams in Hannover and Dresden (Germany) and for which there is detailed information regarding injury patterns and collision speeds. The accident documentations can be regarded as representative and constitute a random sample with statistic weighing of the data. Altogether 143 cases of lower leg fractures (Tibia/ Fibula) with x-rays of pedestrians and 79 cases of bicyclists were differentiated according to new and old vehicles (year of manufacture before/after 1995). The bumper shapes were divided into classical types (protruding pronouncedly/ protruding integrated /integrated rounded). Besides the injuries to the lower leg, those to thighs and feet were also regarded, and the injury conditions involving the head and trunk were included in the kinematic analytics.
Performance improvement of a large capacity GM cryocooler
NASA Astrophysics Data System (ADS)
Wang, C.; Olesh, A.; Cosco, J.
2017-12-01
This paper presents the improvement of a large GM cryocooler, Cryomech model AL600, based on redesigning a cold head stem seal, regenerator, heat exchanger and displacer bumper as well as optimizing operating parameters. The no-load temperature is reduced from 26.6 K to 23.4 K. The cooling capacity is improved from 615 W to 701W at 80 K with a power input of 12.5 kW. It has the highest relative Carnot Efficiency at 15.4%. The vibration of AL600 is investigated experimentally. The new displacer bumper significantly reduces the vibration force on the room temperature flange by 82 % from 520 N to 93 N.
BUMPER: the Bayesian User-friendly Model for Palaeo-Environmental Reconstruction
NASA Astrophysics Data System (ADS)
Holden, Phil; Birks, John; Brooks, Steve; Bush, Mark; Hwang, Grace; Matthews-Bird, Frazer; Valencia, Bryan; van Woesik, Robert
2017-04-01
We describe the Bayesian User-friendly Model for Palaeo-Environmental Reconstruction (BUMPER), a Bayesian transfer function for inferring past climate and other environmental variables from microfossil assemblages. The principal motivation for a Bayesian approach is that the palaeoenvironment is treated probabilistically, and can be updated as additional data become available. Bayesian approaches therefore provide a reconstruction-specific quantification of the uncertainty in the data and in the model parameters. BUMPER is fully self-calibrating, straightforward to apply, and computationally fast, requiring 2 seconds to build a 100-taxon model from a 100-site training-set on a standard personal computer. We apply the model's probabilistic framework to generate thousands of artificial training-sets under ideal assumptions. We then use these to demonstrate both the general applicability of the model and the sensitivity of reconstructions to the characteristics of the training-set, considering assemblage richness, taxon tolerances, and the number of training sites. We demonstrate general applicability to real data, considering three different organism types (chironomids, diatoms, pollen) and different reconstructed variables. In all of these applications an identically configured model is used, the only change being the input files that provide the training-set environment and taxon-count data.
Duffy, Michael F; Stuberg, Wayne; DeJong, Stacey; Gold, Kurt V; Nystrom, N Ake
2004-09-01
Case report of a patient with a whiplash-associated disorder following a bumper car collision. Imaging studies failed to provide an anatomic explanation for the debilitating symptoms. To report a chronic, debilitating pain syndrome after a low-velocity bumper car collision while using complex range-of-motion data for the diagnosis, prognosis, and surgical indication in whiplash-associated disorder. The controversy of whiplash-associated disorder mainly concerns pathophysiology and collision dynamics. Although many investigations attempt to define a universal lesion or determine a threshold of force that may cause permanent injury, no consensus has been reached. Eight years after a low-velocity collision, the patient underwent surgical excision of multiple painful trigger points in the posterior neck. Computerized motion analysis was used for pre- and postoperative evaluations. Surgical treatment resulted in an increase in total active range of motion by 20%, reduced intake of pain medication, doubled the number of work hours, and generally led to a dramatic improvement in quality of life. This case of whiplash-associated disorder after a low-velocity collision highlights the difficulty in defining threshold of injury in regard to velocity. It also illustrates the value of computerized motion analysis in confirming the diagnosis of whiplash-associated disorder and in the evaluation of prognosis and treatment.
Modelling human behaviour in a bumper car ride using molecular dynamics tools: a student project
NASA Astrophysics Data System (ADS)
Buendía, Jorge J.; Lopez, Hector; Sanchis, Guillem; Pardo, Luis Carlos
2017-05-01
Amusement parks are excellent laboratories of physics, not only to check physical laws, but also to investigate if those physical laws might also be applied to human behaviour. A group of Physics Engineering students from Universitat Politècnica de Catalunya has investigated if human behaviour, when driving bumper cars, can be modelled using tools borrowed from the analysis of molecular dynamics simulations, such as the radial and angular distribution functions. After acquiring several clips and obtaining the coordinates of the cars, those magnitudes are computed and analysed. Additionally, an analogous hard disks system is simulated to compare its distribution functions to those obtained from the cars’ coordinates. Despite the clear difference between bumper cars and a hard disk-like particle system, the obtained distribution functions are very similar. This suggests that there is no important effect of the individuals in the collective behaviour of the system in terms of structure. The research, performed by the students, has been undertaken in the frame of a motivational project designed to approach the scientific method for university students named FISIDABO. This project offers both the logistical and technical support to undertake the experiments designed by students at the amusement park of Barcelona TIBIDABO and accompanies them all along the scientific process.
Permanent superconducting magnets for space applications
NASA Technical Reports Server (NTRS)
Weinstein, Roy
1994-01-01
Work has been done to develop superconducting trapped field magnets (TFM's) and to apply them to a bumper-tether device for magnetic docking of spacecraft. The quality parameters for TFM's are J(c), the critical current of the superconductor, and d, the diameter of the superconducting tile. During this year we have doubled d, for production models, from 1 cm to 2 cm. This was done by means of seeding, an improved temperature profile in processing, and the addition of 1 percent Pt to the superconductor chemistry. Using these tiles we have set increasing records for the fields' permanent magnets. Magnets fabricated from old 1 cm tiles trapped 1.52 Tesla at 77K, 4.0T at 65K and 7.0T at 55K. The second of these fields broke a 17 year old record set at Stanford. The third field broke our own record. More recently using 2 cm tiles, we have trapped 2.3T at 77K, and 5.3T at 65K. We expect to trap lOT at 55K in this magnet in the near future. We have also achieved increases in J(c) using a method we developed for seeding U-235, and subsequently bombarding with neutrons. This method doubles J(c). We have not yet fabricated magnets from these tiles. During this year we have increased production yields from 15 percent to 95 percent. We have explored the properties of a magnetic bumper-tether for spacecraft. We have measured the bumper forces, and their dependence on time, distance, and the field of the ordinary ferromagnet (used together with a TFM). We have accounted for 85 percent of the collision energy, and its transformation to magnetic energy and heat energy. We have learned to control the relative bumper and tether forces by controlling TFM and ferromagnetic field strengths.
Scattina, Alessandro; Mo, Fuhao; Masson, Catherine; Avalle, Massimiliano; Arnoux, Pierre Jean
2018-01-30
This work aims at investigating the influence of some front-end design parameters of a passenger vehicle on the behavior and damage occurring in the human lower limbs when impacted in an accident. The analysis is carried out by means of finite element analysis using a generic car model for the vehicle and the lower limbs model for safety (LLMS) for the purpose of pedestrian safety. Considering the pedestrian standardized impact procedure (as in the 2003/12/EC Directive), a parametric analysis, through a design of experiments plan, was performed. Various material properties, bumper thickness, position of the higher and lower bumper beams, and position of pedestrian, were made variable in order to identify how they influence the injury occurrence. The injury prediction was evaluated from the knee lateral flexion, ligament elongation, and state of stress in the bone structure. The results highlighted that the offset between the higher and lower bumper beams is the most influential parameter affecting the knee ligament response. The influence is smaller or absent considering the other responses and the other considered parameters. The stiffness characteristics of the bumper are, instead, more notable on the tibia. Even if an optimal value of the variables could not be identified trends were detected, with the potential of indicating strategies for improvement. The behavior of a vehicle front end in the impact against a pedestrian can be improved optimizing its design. The work indicates potential strategies for improvement. In this work, each parameter was changed independently one at a time; in future works, the interaction between the design parameters could be also investigated. Moreover, a similar parametric analysis can be carried out using a standard mechanical legform model in order to understand potential diversities or correlations between standard tools and human models.
ERIC Educational Resources Information Center
Walker, Joseph J.; Lotz, Condit
1982-01-01
The authors describe an incidental learning approach using supplementary reading sources such as bumper stickers, t-shirts, and novelty buttons to encourage gifted students' analysis and synthesis skills. (CL)
MLIBlast: A program to empirically predict hypervelocity impact damage to the Space Station
NASA Technical Reports Server (NTRS)
Rule, William K.
1991-01-01
MLIBlast is described, which consists of a number of DOC PC based MIcrosoft BASIC program modules written to provide spacecraft designers with empirical predictions of space debris damage to orbiting spacecraft. The Spacecraft wall configuration is assumed to consist of multilayer insulation (MLI) placed between a Whipple style bumper and a pressure wall. Predictions are based on data sets of experimental results obtained from simulating debris impact on spacecraft. One module of MLIBlast facilitates creation of the data base of experimental results that is used by the damage prediction modules of the code. The user has a choice of three different prediction modules to predict damage to the bumper, the MLI, and the pressure wall.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-01
...; input/output assemblies; electromagnetic interference support walls; bumpers; adhesives; sleeves; rubber... shroud assemblies; mechanism bases; storage; busbars; button dim links; electromagnetic interference fans...
Code of Federal Regulations, 2011 CFR
2011-01-01
... § 1632.8 Glossary of terms, for definitions of these items. (2) This definition excludes sleeping bags..., dressing table pads, stroller pads, crib bumpers, and playpen pads. See § 1632.8 Glossary of terms, for...
Code of Federal Regulations, 2014 CFR
2014-01-01
... § 1632.8 Glossary of terms, for definitions of these items. (2) This definition excludes sleeping bags..., dressing table pads, stroller pads, crib bumpers, and playpen pads. See § 1632.8 Glossary of terms, for...
Code of Federal Regulations, 2012 CFR
2012-01-01
... § 1632.8 Glossary of terms, for definitions of these items. (2) This definition excludes sleeping bags..., dressing table pads, stroller pads, crib bumpers, and playpen pads. See § 1632.8 Glossary of terms, for...
Tube Feeding Troubleshooting Guide
... in place. (For example, does it have a balloon, a mushroom bumper, or other internal device, or ... Frequent vomiting. • See “Nausea and Vomiting” page 3. Balloon deflates or bursts. • Be sure the balloon under ...
49 CFR 571.301 - Standard No. 301; Fuel system integrity.
Code of Federal Regulations, 2010 CFR
2010-10-01
... alcohol fuel vehicles. Each vehicle shall have means that prevent any hose made of vinyl plastic or rubber... the vehicle, including bumpers and molding, but excluding such components as exterior mirrors...
49 CFR Appendix C to Part 591 - Power of Attorney and Agreement
Code of Federal Regulations, 2010 CFR
2010-10-01
... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) IMPORTATION OF VEHICLES AND EQUIPMENT SUBJECT TO FEDERAL SAFETY, BUMPER AND THEFT PREVENTION STANDARDS Pt. 591, App. C Appendix C to...
First wall design of aluminum alloy R-tokamak
NASA Astrophysics Data System (ADS)
Hamada, Y.; Matsuoka, K.; Ogawa, Y.; Kitagawa, S.; Toi, K.; Yamazaki, K.; Abe, Y.; Amano, T.; Fujita, J.; Kaneko, O.; Kawahata, K.; Kuroda, T.; Matsuura, K.; Midzuno, Y.; Naitou, H.; Noda, N.; Ohkubo, K.; Oka, Y.; Sakurai, K.; Tanahashi, S.; Watari, T.
1984-05-01
A design study of a low-activation D-T tokamak Reacting Plasma Project In Nagoya has been finished. The study emphasizes the vacuum vessel and the bumper limiter. Our choice of materials (aluminum vacuum vessel, copper conductors, aluminum TF coil case and lead shield) results in a radiation level of about 1 × 10 -3 times that of a TFTR type design, and 1 × 10 -4 times that of JET type design, at 2 weeks after one D-T shot. Thick graphite tiles will be fixed directly on the aluminum vacuum vessel using aluminum spring washers and bolts. With this simplified structure of the bumper limiter, the inner surface temperature of the thick aluminum vacuum vessel will be less than 120°C which is required to reduce the overaging effect of the aluminum alloy.
Rapid detection and identification of pedestrian impacts using a distributed sensor network
NASA Astrophysics Data System (ADS)
Kim, Andrew C.; Chang, Fu-Kuo
2005-05-01
Pedestrian fatalities from automobile accidents often occur as a result of head injuries suffered from impacts with an automobile front end. Active pedestrian protection systems with proper pedestrian recognition algorithms can protect pedestrians from such head trauma. An investigation was conducted to assess the feasibility of using a network of piezoelectric sensors mounted on the front bumper beam of an automobile to discriminate between impacts with "pedestrian" and "non-pedestrian" objects. This information would be used to activate a safety device (e.g., external airbag or pop-up hood) to provide protection for the vulnerable pedestrian. An analytical foundation for the object-bumper impact problem will be presented, as well as the classical beam impact theory. The mechanical waves that propagate in the structure from an external impact contain a wealth of information about the specifics of a particular impact -- object mass, size, impact speed, etc. -- but most notably the object stiffness, which identifies the impacted object. Using the frequency content of the sensor signals, it can be shown that impacts with a "pedestrian" object of varying size, weight, and speed can be easily differentiated from impacts with other "non-pedestrian" objects. Simulation results will illustrate this phenomenon, and experimental tests will verify the results. A comprehensive series of impact tests were performed for validation, using both a stationary front bumper with a drop-pendulum impactor and a moving car with stationary impact objects. Results from both tests will be presented.
HVI Ballistic Performance Characterization of Non-Parallel Walls
NASA Technical Reports Server (NTRS)
Bohl, William; Miller, Joshua; Christiansen, Eric
2012-01-01
The Double-Wall, "Whipple" Shield [1] has been the subject of many hypervelocity impact studies and has proven to be an effective shield system for Micro-Meteoroid and Orbital Debris (MMOD) impacts for spacecraft. The US modules of the International Space Station (ISS), with their "bumper shields" offset from their pressure holding rear walls provide good examples of effective on-orbit use of the double wall shield. The concentric cylinder shield configuration with its large radius of curvature relative to separation distance is easily and effectively represented for testing and analysis as a system of two parallel plates. The parallel plate double wall configuration has been heavily tested and characterized for shield performance for normal and oblique impacts for the ISS and other programs. The double wall shield and principally similar Stuffed Whipple Shield are very common shield types for MMOD protection. However, in some locations with many spacecraft designs, the rear wall cannot be modeled as being parallel or concentric with the outer bumper wall. As represented in Figure 1, there is an included angle between the two walls. And, with a cylindrical outer wall, the effective included angle constantly changes. This complicates assessment of critical spacecraft components located within outer spacecraft walls when using software tools such as NASA's BumperII. In addition, the validity of the risk assessment comes into question when using the standard double wall shield equations, especially since verification testing of every set of double wall included angles is impossible.
16 CFR § 1632.1 - Definitions.
Code of Federal Regulations, 2013 CFR
2013-01-01
... § 1632.8 Glossary of terms, for definitions of these items. (2) This definition excludes sleeping bags..., dressing table pads, stroller pads, crib bumpers, and playpen pads. See § 1632.8 Glossary of terms, for...
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 6 2010-10-01 2010-10-01 false Application. 567.2 Section 567.2 Transportation..., DEPARTMENT OF TRANSPORTATION CERTIFICATION § 567.2 Application. (a) This part applies to manufacturers... Safety, Bumper and Theft Prevention Standards. ...
49 CFR 591.5 - Declarations required for importation.
Code of Federal Regulations, 2014 CFR
2014-10-01
... roads and thus is not a motor vehicle subject to the Federal motor vehicle safety, bumper, and theft... such as mirrors, wipers, or tire and rim assemblies, or minor finishing operations such as painting...
49 CFR 591.5 - Declarations required for importation.
Code of Federal Regulations, 2010 CFR
2010-10-01
... roads and thus is not a motor vehicle subject to the Federal motor vehicle safety, bumper, and theft... such as mirrors, wipers, or tire and rim assemblies, or minor finishing operations such as painting...
49 CFR 591.5 - Declarations required for importation.
Code of Federal Regulations, 2011 CFR
2011-10-01
... roads and thus is not a motor vehicle subject to the Federal motor vehicle safety, bumper, and theft... such as mirrors, wipers, or tire and rim assemblies, or minor finishing operations such as painting...
49 CFR 591.5 - Declarations required for importation.
Code of Federal Regulations, 2012 CFR
2012-10-01
... roads and thus is not a motor vehicle subject to the Federal motor vehicle safety, bumper, and theft... such as mirrors, wipers, or tire and rim assemblies, or minor finishing operations such as painting...
49 CFR 591.5 - Declarations required for importation.
Code of Federal Regulations, 2013 CFR
2013-10-01
... roads and thus is not a motor vehicle subject to the Federal motor vehicle safety, bumper, and theft... such as mirrors, wipers, or tire and rim assemblies, or minor finishing operations such as painting...
77 FR 43545 - Airworthiness Directives; Bombardier, Inc. Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-25
... Bombardier, Inc. Model DHC-8-400 series airplanes. The existing AD currently requires a modification to trim... the MLG tires, Bombardier Aerospace has developed a modification to trim the edge of the bumper plate...
Code of Federal Regulations, 2011 CFR
2011-07-01
... validation sticker. (1) One decal will be affixed to the left front bumper (operator's side) of a four-wheel... registration information. Evidence of compliance will be documented by the issuance and display of a new 3-year...
INJECTION SYSTEM DESIGN FOR THE BSNS/RCS.
DOE Office of Scientific and Technical Information (OSTI.GOV)
WEI, J.; TANG, J.Y.; CHEN, Y.
2006-06-23
The BSNS injection system is designed to take one uninterrupted long drift in one of the four dispersion-free straight sections to host all the injection devices. Painting bumper magnets are used for both horizontal and vertical phase space painting. Closed-orbit bumper magnets are used for facilitating the installation of the injection septa and decreasing proton traversal in the stripping foil. Even with large beam emittance of about 300 {pi}mm.mrad used, BSNS/RCS still approaches the space charge limit during the injection/trapping phase for the accumulated particles of 1.9*10{sup 13} and at the low injection energy of 80 MeV. Uniform-like beam distributionmore » by well-designed painting scheme is then obtained to decrease the tune shift/spread. ORBIT code is used for the 3D simulations. Upgrading to higher injection energy has also been considered.« less
Coaxial tube array space transmission line characterization
NASA Technical Reports Server (NTRS)
Switzer, Colleen A.; Bents, David J.
1987-01-01
The coaxial tube array tether/transmission line used to connect an SP-100 nuclear power system to the space station was characterized over the range of reactor-to-platform separation distances of 1 to 10 km. Characterization was done with respect to array performance, physical dimensions and masses. Using a fixed design procedure, a family of designs was generated for the same power level (300 kWe), power loss (1.5 percent), and meteoroid survival probability (99.5 percent over 10 yr). To differentiate between vacuum insulated and gas insulated lines, two different maximum values of the E field were considered: 20 kV/cm (appropriate to vacuum insulation) and 50 kV/cm (compressed SF6). Core conductor, tube, bumper, standoff, spacer and bumper support dimensions, and masses were also calculated. The results of the characterization show mainly how transmission line size and mass scale with reactor-to-platform separation distance.
Spacecraft outer thermal blankets as hypervelocity impact bumpers
NASA Astrophysics Data System (ADS)
Cour-Palais, B. G.
1996-05-01
A thermal barrier consisting of a woven fabric outer layer followed by several layers of aluminized mylar insulation has been the primary impact protection against micrometeoroid and orbital impacts for many spacecraft currently in orbit. This paper examines its effectiveness as a hypervelocity "bumper" based on the performance of a NASA space suit. In this case, the thermal barrier consisted of a fabric layer followed by five layers of the aluminized mylar, which shielded either an aluminum rear wall or a rubberized pressure garment. The total areal density of the fabric and mylar layers was 0.052 g/cm2 and the fabric stand-off was 4 mm from the protected surfaces, with the aluminized mylar filling the space. Test results obtained with hypervelocity aluminum projectile impacts up to 8.5 km/s on the thermal barrier and aluminum wall are described, and a semi-empirical equation for this type of shielding is suggested.
Sharif Hossain, A B M; Ibrahim, Nasir A; AlEissa, Mohammed Saad
2016-09-01
The innovative study was carried out to produce nano-cellulose based bioplastic biomaterials for vehicle use coming after bioprocess technology. The data show that nano-cellulose particle size was 20 nm and negligible water absorption was 0.03% in the bioplastic. Moreover, burning test, size and shape characterizations, spray coating dye, energy test and firmness of bioplastic have been explored and compared with the standardization of synthetic vehicle plastic bumper following the American Society for Testing and Materials (ASTM). Tensile test was observed 120 MPa/kg m(3). In addition to that pH and cellulose content were found positive in the bioplastic compared to the synthetic plastic. Chemical tests like K, CO3, Cl2, Na were determined and shown positive results compared to the synthetic plastic using the EN-14214 (European Norm) standardization.
International Space Station (ISS) Meteoroid/Orbital Debris Shielding
NASA Technical Reports Server (NTRS)
Christiansen, Eric L.
1999-01-01
Design practices to provide protection for International Space Station (ISS) crew and critical equipment from meteoroid and orbital debris (M/OD) Impacts have been developed. Damage modes and failure criteria are defined for each spacecraft system. Hypervolocity Impact -1 - and analyses are used to develop ballistic limit equations (BLEs) for each exposed spacecraft system. BLEs define Impact particle sizes that result in threshold failure of a particular spacecraft system as a function of Impact velocity, angles and particle density. The BUMPER computer code Is used to determine the probability of no penetration (PNP) that falls the spacecraft shielding based on NASA standard meteoroid/debris models, a spacecraft geometry model, and the BLEs. BUMPER results are used to verify spacecraft shielding requirements Low-weight, high-performance shielding alternatives have been developed at the NASA Johnson Space Center (JSC) Hypervelocity Impact Technology Facility (HITF) to meet spacecraft protection requirements.
NASA Technical Reports Server (NTRS)
Susko, M.
1984-01-01
A review of meteoroid flux measurements and models for low orbital altitudes of the Space Station has been made in order to provide information that may be useful in design studies and laboratory hypervelocity impact tests which simulate micrometeoroids in space for design of the main wall of the Space Station. This report deals with the meteoroid flux mass model, the defocusing and shielding factors that affect the model, the probability of meteoroid penetration of the main wall of a Space Station. Whipple (1947) suggested a meteoroid bumper, a thin shield around the spacecraft at some distance from the wall, as an effective device for reducing penetration, which has been discussed in this report. The equations of the probability of meteoroid penetration, the average annual cumulative total flux, and the equations for the thickness of the main wall and the bumper are presented in this report.
Coaxial tube array space transmission line characterization
NASA Astrophysics Data System (ADS)
Switzer, Colleen A.; Bents, David J.
The coaxial tube array tether/transmission line used to connect an SP-100 nuclear power system to the space station was characterized over the range of reactor-to-platform separation distances of 1 to 10 km. Characterization was done with respect to array performance, physical dimensions and masses. Using a fixed design procedure, a family of designs was generated for the same power level (300 kWe), power loss (1.5 percent), and meteoroid survival probability (99.5 percent over 10 yr). To differentiate between vacuum insulated and gas insulated lines, two different maximum values of the E field were considered: 20 kV/cm (appropriate to vacuum insulation) and 50 kV/cm (compressed SF6). Core conductor, tube, bumper, standoff, spacer and bumper support dimensions, and masses were also calculated. The results of the characterization show mainly how transmission line size and mass scale with reactor-to-platform separation distance.
Kim, Boowook; Yoon, Jin-Ha; Choi, Byung-Soon; Shin, Yong Chul
2013-01-01
A 46-year-old man who had worked as a bumper spray painter in an automobile body shop for 15 years developed lung cancer. The patient was a nonsmoker with no family history of lung cancer. To determine whether the cancer was related to his work environment, we assessed the level of exposure to carcinogens during spray painting, sanding, and heat treatment. The results showed that spray painting with yellow paint increased the concentration of hexavalent chromium in the air to as much as 118.33 μg/m3. Analysis of the paint bulk materials showed that hexavalent chromium was mostly found in the form of lead chromate. Interestingly, strontium chromate was also detected, and the concentration of strontium chromate increased in line with the brightness of the yellow color. Some paints contained about 1% crystalline silica in the form of quartz. PMID:24422178
Otoliths reveal a diverse age structure for humper lake trout in Lake Superior
Burnham-Curtis, Mary K.; Bronte, Charles R.
1996-01-01
Humpers are one of at least three morphological variants of wild lake trout Salvelinus namaycush that maintain self-sustaining populations in Lake Superior. In an early study, bumpers from Isle Royale were shown to have a sharply truncated age distribution that was attributed to high mortality after age 11, but we suspected that these fish were underaged. In August of 1989 and 1992 we collected spawning humper lake trout from the same area and estimated their ages using both scales and sagittal otoliths. Humpers in our sample ranged from 5 to 13 years, based on scale annuli, but counts of sagitta annuli revealed ages of 8 to 28 years. Individual discrepancies between ages from scales and sagittae varied from –2 to 20 years, but differences between scale and otolith ages did not increase with individual age. We applied the von Bertalanffy growth model to the humper length-at-age data to indirectly assess the accuracy of aging estimates. The model significantly overestimated mean asymptotic length when scale ages were used, but the mean asymptotic length estimate was more similar to observed lengths when sagitta ages were used. Our results corroborate evidence that bumpers in Lake Superior grow more slowly and mature at a smaller size than lean lake trout; however, the age composition of bumpers is more diverse than previously thought. This particular population experiences little or no exploitation; the presence of older fish provides one standard by which the success of lake trout rehabilitation programs can be evaluated and emphasizes the need for accurate aging techniques.
11 CFR 100.22 - Expressly advocating (2 U.S.C. 431(17)).
Code of Federal Regulations, 2010 CFR
2010-01-01
... slogan(s) or individual word(s), which in context can have no other reasonable meaning than to urge the election or defeat of one or more clearly identified candidate(s), such as posters, bumper stickers...
Self-Resetting Energy Absorber
NASA Technical Reports Server (NTRS)
De La Fuente, Horacio M.; Nagy, Kornel; Wesselski, Clarence J.
1992-01-01
Device uses friction to dissipate kinetic energy. When moving mass pushes in one direction, it offers substantial friction. Pushed in opposite direction, it offers negligible friction. Built-in spring resets for another shock-absorption cycle. Used in industrial machinery, automobile bumpers and suspensions, and parachute lanyards.
Passenger vehicles sustain huge damage in 5 Mph tests
DOT National Transportation Integrated Search
2000-04-15
Seventeen new cars, all 1999 and 2000 models, turned in mostly disappointing results in 5 mph crash tests conducted to assess how well the bumpers resist costly damage in the kinds of impacts that frequently occur in commuter traffic and parking lots...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-02
... [Docket No. NHTSA-2009-0066; Notice 2] RIN 2127-AK40 Civil Penalties AGENCY: National Highway Traffic... civil penalty amounts for violations of motor vehicle safety requirements involving school buses, bumper... theft protection requirements. This action is taken pursuant to the Federal Civil Monetary Penalty...
49 CFR 581.7 - Test procedures.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 7 2013-10-01 2013-10-01 false Test procedures. 581.7 Section 581.7... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) BUMPER STANDARD § 581.7 Test procedures. (a) Longitudinal impact test procedures. (1) Impact the vehicle's front surface and its rear surface two times each...
49 CFR 581.7 - Test procedures.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 7 2011-10-01 2011-10-01 false Test procedures. 581.7 Section 581.7... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) BUMPER STANDARD § 581.7 Test procedures. (a) Longitudinal impact test procedures. (1) Impact the vehicle's front surface and its rear surface two times each...
Code of Federal Regulations, 2010 CFR
2010-10-01
..., DEPARTMENT OF TRANSPORTATION (CONTINUED) IMPORTATION OF VEHICLES AND EQUIPMENT SUBJECT TO FEDERAL SAFETY, BUMPER AND THEFT PREVENTION STANDARDS § 591.3 Applicability. This part applies to any person offering a motor vehicle or item of motor vehicle equipment for importation into the United States. [55 FR 11378...
49 CFR 591.8 - Conformance bond and conditions.
Code of Federal Regulations, 2010 CFR
2010-10-01
... SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) IMPORTATION OF VEHICLES AND EQUIPMENT SUBJECT TO FEDERAL SAFETY, BUMPER AND THEFT PREVENTION STANDARDS § 591.8 Conformance bond and conditions. (a) The bond required under section 591.6(c) for importation of a vehicle not originally manufactured...
49 CFR 592.9 - Forfeiture of bond.
Code of Federal Regulations, 2010 CFR
2010-10-01
... Federal motor vehicle safety, bumper, and theft prevention standard in effect at the time the vehicle was... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) REGISTERED IMPORTERS OF VEHICLES NOT ORIGINALLY MANUFACTURED TO CONFORM TO THE FEDERAL MOTOR VEHICLE SAFETY STANDARDS § 592.9 Forfeiture of bond. A Registered...
49 CFR 591.6 - Documents accompanying declarations.
Code of Federal Regulations, 2010 CFR
2010-10-01
... SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) IMPORTATION OF VEHICLES AND EQUIPMENT SUBJECT TO FEDERAL SAFETY, BUMPER AND THEFT PREVENTION STANDARDS § 591.6 Documents accompanying... public roads, or that the equipment item was not manufactured for use on a motor vehicle or is not an...
49 CFR 581.7 - Test procedures.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 7 2012-10-01 2012-10-01 false Test procedures. 581.7 Section 581.7... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) BUMPER STANDARD § 581.7 Test procedures. (a) Longitudinal impact test procedures. (1) Impact the vehicle's front surface and its rear surface two times each...
Empirical predictions of hypervelocity impact damage to the space station
NASA Technical Reports Server (NTRS)
Rule, W. K.; Hayashida, K. B.
1991-01-01
A family of user-friendly, DOS PC based, Microsoft BASIC programs written to provide spacecraft designers with empirical predictions of space debris damage to orbiting spacecraft is described. The spacecraft wall configuration is assumed to consist of multilayer insulation (MLI) placed between a Whipple style bumper and the pressure wall. Predictions are based on data sets of experimental results obtained from simulating debris impacts on spacecraft using light gas guns on Earth. A module of the program facilitates the creation of the data base of experimental results that are used by the damage prediction modules of the code. The user has the choice of three different prediction modules to predict damage to the bumper, the MLI, and the pressure wall. One prediction module is based on fitting low order polynomials through subsets of the experimental data. Another prediction module fits functions based on nondimensional parameters through the data. The last prediction technique is a unique approach that is based on weighting the experimental data according to the distance from the design point.
40 CFR Table 1 to Subpart E of... - Product-Weighted Reactivity Limits by Coating Category
Code of Federal Regulations, 2014 CFR
2014-07-01
... Primers ABP 1.55 Automotive Bumper and Trim Products ABT 1.75 Aviation or Marine Primers AMP 2.00 Aviation... Finish—Engine Enamel EEE 1.70 Exact Match Finish—Automotive EFA 1.50 Exact Match Finish—Industrial EFI 2...
Jacks--A Study of Simple Machines.
ERIC Educational Resources Information Center
Parsons, Ralph
This vocational physics individualized student instructional module on jacks (simple machines used to lift heavy objects) contains student prerequisites and objectives, an introduction, and sections on the ratchet bumper jack, the hydraulic jack, the screw jack, and load limitations. Designed with a laboratory orientation, each section consists of…
Research perspectives overview at DBNRRC to maintain sustainable food security
USDA-ARS?s Scientific Manuscript database
The research issues that the Dale Bumpers National Rice Research Center (DBNRRC) is addressing for the rice industry and research community are 1) changing rice production practices, 2) diminishing irrigation resources, 3) loss of export markets due to poor quality, 4) emerging high value specialty...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-28
..., Office of Vehicle Safety Compliance (NVS-223), National Highway Traffic Safety Administration, West... INFORMATION: National Highway Traffic Safety Administration Title: Importation of Vehicles and Equipment Subject to the Federal Motor Vehicle Safety, Bumper, and Theft Prevention Standards. OMB Number: 2127-0002...
ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A BUMPER REFINISHING PLANT
The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at se...
Multi-Shock Shield Performance at 15 MJ for Catalogued Debris
NASA Technical Reports Server (NTRS)
Miller, J. E.; Davis, B. A.; Christiansen, E. L.; Lear, D. M.
2015-01-01
While orbital debris of ten centimeters or more are tracked and catalogued, the difficulty of finding and accurately accounting for forces acting on the objects near the ten centimeter threshold results in both uncertainty of their presence and location. These challenges result in difficult decisions for operators balancing potential costly operational approaches with system loss risk. In this paper, the assessment of the feasibility of protecting a spacecraft from this catalogued debris is described using numerical simulations and a test of a multi-shock shield system against a cylindrical projectile impacting normal to the surface with approximately 15 MJ of kinetic energy. The hypervelocity impact test has been conducted at the Arnold Engineering Development Complex (AEDC) with a 598 g projectile at 6.905 km/s on a NASA supplied multi-shock shield. The projectile used is a hollow aluminum and nylon cylinder with an outside diameter of 8.6 cm and length of 10.3 cm. Figure 1 illustrates the multi-shock shield test article, which consisted of five separate bumpers, four of which are fiberglass fabric and one of steel mesh, and two rear walls, each consisting of Kevlar fabric. The overall length of the test article was 2.65 m. The test article was a 5X scaled-up version of a smaller multi-shock shield previously tested using a 1.4 cm diameter aluminum projectile for an inflatable module project. The distances represented by S1 and S1/2 in the figure are 61 cm and 30.5 cm, respectively. Prior to the impact test, hydrodynamic simulations indicated that some enhancement to the standard multi-shock system is needed to address the effects of the cylindrical shape of the projectile. Based on the simulations, a steel mesh bumper has been added to the shield configuration to enhance the fragmentation of the projectile. The AEDC test occurred as planned, and the modified NASA multi-shock shield successfully stopped 598 g projectile using 85.6 kg/m(exp 2). The fifth bumper layer remained in tact, although it was torn free from its support structure and thrown into the first rear wall. The outer Kevlar layer of the first rear wall tore likely from the impact of the fifth bumper's support structure, but the back of the rear wall was intact. No damage occurred to the second rear wall, or to the witness plate behind the target.
30 CFR 56.9301 - Dump site restraints.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Dump site restraints. 56.9301 Section 56.9301 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... § 56.9301 Dump site restraints. Berms, bumper blocks, safety hooks, or similar impeding devices shall...
30 CFR 56.9301 - Dump site restraints.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Dump site restraints. 56.9301 Section 56.9301 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... § 56.9301 Dump site restraints. Berms, bumper blocks, safety hooks, or similar impeding devices shall...
30 CFR 57.9301 - Dump site restraints.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Dump site restraints. 57.9301 Section 57.9301 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... § 57.9301 Dump site restraints. Berms, bumper blocks, safety hooks, or similar impeding devices shall...
Sandia National Laboratories: Bumper crop of partnerships
of IR Dynamics LLC of Santa Fe, is working with Sandia's Nelson Bell (1815) through a Cooperative Research and Development Agreement. IR Dynamics is developing thermochromic materials to control infrared analysis of human visual perception and cognition with dynamic content. IR Dynamics LLC: The Santa Fe
2008 Tactical Wheeled Vehicles Conference (TWV) Volume 1
2008-02-05
additional LSAC cabs FMTV Gunners Restraint (2,022 LSAC; 1,855 RACK) Counterweight bumper for M1078 Cargo with LSAC Cab and GPK 3 Jan 08NDIA TWV Conference...Objective Gunner Protection Kits to support Up-Armored HMMWV’s GPK Upgrade Program. Partnerships: Ensured partnerships with commercial manufacturers
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-24
.... On its domestic sales, Benteler would be able to choose the duty rate during customs entry procedures...: Metal stampings (crash cans, reinforcement plates, flange plates); bumper beams; toe hooks; cross member shells; side tubes; steel blanks; brackets; gussets; closing plates; castings of aluminum; flat-rolled...
49 CFR 591.7 - Restrictions on importations.
Code of Federal Regulations, 2010 CFR
2010-10-01
... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) IMPORTATION OF VEHICLES AND EQUIPMENT SUBJECT TO FEDERAL SAFETY, BUMPER AND THEFT PREVENTION STANDARDS § 591.7 Restrictions on importations. (a) A vehicle or... a vehicle or equipment item under § 591.5(j) does not intend to export or destroy the vehicle or...
49 CFR 567.4 - Requirements for manufacturers of motor vehicles.
Code of Federal Regulations, 2010 CFR
2010-10-01
... applicable Federal motor vehicle safety, bumper, and theft prevention standards in effect on the date of... statement: “This vehicle conforms to all applicable Federal motor vehicle safety and theft prevention... conforms to the applicable Federal motor vehicle theft prevention standard in effect on the date of...
Rice diversity panels available through the genetic stocks oryza collection
USDA-ARS?s Scientific Manuscript database
The Genetic Stocks Oryza (GSOR) Collection was established in 2004 at the USDA-ARS, Dale Bumpers National Rice Research Center (DBNRRC) located in Stuttgart, AR. The mission of GSOR is to provide unique genetic resources to the rice research community for genetic and genomics related research. GSOR ...
49 CFR Appendix C to Part 591 - Power of Attorney and Agreement
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 7 2011-10-01 2011-10-01 false Power of Attorney and Agreement C Appendix C to Part 591 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY... EQUIPMENT SUBJECT TO FEDERAL SAFETY, BUMPER AND THEFT PREVENTION STANDARDS Pt. 591, App. C Appendix C to...
40 CFR Table 1 to Subpart E of... - Product-Weighted Reactivity Limits by Coating Category
Code of Federal Regulations, 2011 CFR
2011-07-01
... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for Aerosol Coatings... primers ABP 1.55 Automotive Bumper and Trim Products ABT 1.75 Aviation or Marine Primers AMP 2.00 Aviation...
USDA-ARS?s Scientific Manuscript database
Rice feeds around 3.5 billion people and provides a significant proportion of calories for many of the world’s poor. The USA is a major producer and exporter of rice. The USDA/ARS Dale Bumpers National Rice Research Center (DBNRRC) is located in the heart of the southern USA rice growing region in A...
49 CFR 567.5 - Requirements for manufacturers of vehicles manufactured in two or more stages.
Code of Federal Regulations, 2010 CFR
2010-10-01
... applicable Federal Motor Vehicle Safety Standards, [and Bumper and Theft Prevention Standards, if applicable... 49 Transportation 6 2010-10-01 2010-10-01 false Requirements for manufacturers of vehicles... CERTIFICATION § 567.5 Requirements for manufacturers of vehicles manufactured in two or more stages. (a...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-14
... Management receives them by February 28, 2011. ADDRESSES: Comments should refer to the docket and notice...://www.regulations.gov . Follow the online instructions for submitting comments. Mail: Docket Management... documentary proof of the vehicle's destruction, exportation, or abandonment within 15 days from the date of...
The Media Is the Message: Using the Media to Improve School Attendance.
ERIC Educational Resources Information Center
Nyangoni, Betty
The problem of truancy and irregular school attendance is widespread in urban, suburban, and rural school districts. The media have interesting and far-reaching capabilities for combating this problem. Possible uses of the print media in this area include posters, bumper stickers, billboards, leaflets and flyers, handouts, buttons, T-shirts,…
ERIC Educational Resources Information Center
Nunn, Lisa M.; Bolt, Sophia C.
2015-01-01
College campuses are known to be heteronormative environments that often foster heterosexism and homophobia. There is a broad call for lesbian, gay, bisexual, transgender, and queer (LGBTQ) awareness-building curricula as one avenue for positive change in campus climates. This study interrogates the effects of an experiential learning activity…
Microstructure and mechanical properties of sheep horn.
Zhu, Bing; Zhang, Ming; Zhao, Jian
2016-07-01
The sheep horn presents outstanding mechanical properties of impact resistance and energy absorption, which suits the need of the vehicle bumper design, but the mechanism behind this phenomenon is less investigated. The microstructure and mechanical properties of the sheep horn of Small Tailed Han Sheep (Ovis aries) living in northeast China were investigated in this article. The effect of sampling position and orientation of the sheep horn sheath on mechanical properties were researched by tensile and compression tests. Meanwhile, the surface morphology and microstructure of the sheep horn were observed using scanning electron microscopy (SEM). The formation mechanism of the mechanical properties of the sheep horn was investigated by biological coupling analysis. The analytical results indicated that the outstanding mechanical properties of the sheep horn are determined by configuration, structure, surface morphology and material coupling elements. These biological coupling elements make the sheep horn possess super characteristics of crashworthiness and energy absorption through the internal coupling mechanism. We suppose that these findings would make a difference in vehicle bumper design. Microsc. Res. Tech. 79:664-674, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Metallic materials for mechanical damping capacity applications
NASA Astrophysics Data System (ADS)
Crăciun, R. C.; Stanciu, S.; Cimpoeșu, R.; (Dragoș Ursanu, A. I.; Manole, V.; Paraschiv, P.; Chicet, D. L.
2016-08-01
Some metallic materials exhibit good damping capacity of mechanical energy into thermal energy. This property along with the others metallic characteristics make this materials interesting for a big number of applications. These materials can be used as bumpers in different applications including automotive field. Beside grey cast iron and shape memory alloys few new metallic materials are presented for the supposition of high damping capacity. We analyze the causes that increase the internal friction of some metallic materials and possibilities to enhance this property through different mechanical, physical or chemical methods. Shape memory alloys, especially those based on copper, present a different damping capacity on martensite, austenite or transition state. In the transformation range M ↔A, which in case of copper base shape memory alloys is quite large, the metallic intelligent materials present a high internal friction, almost comparable with natural rubber behavior that can transform mechanical energy into thermal energy till a certain value of the external solicitation. These materials can be used as noise or small vibrations bumpers or even as shock absorbers in automotive industry.
Flexible Shields for Protecting Spacecraft Against Debris
NASA Technical Reports Server (NTRS)
Christiansen, Eric L.; Crews, Jeanne Lee
2004-01-01
A report presents the concept of Flexshield a class of versatile, lightweight, flexible shields for protecting spacecraft against impacts by small meteors and orbiting debris. The Flexshield concept incorporates elements of, but goes beyond, prior spacecraft-shielding concepts, including those of Whipple shields and, more recently, multi-shock shields and multi-shock blankets. A shield of the Flexshield type includes multiple outer layers (called bumpers in the art) made, variously, of advanced ceramic and/or polymeric fibers spaced apart from each other by a lightweight foam. As in prior such shields, the bumpers serve to shock an impinging hypervelocity particle, causing it to disintegrate vaporize, and spread out over a larger area so that it can be stopped by an innermost layer (back sheet). The flexibility of the fabric layers and compressibility of the foam make it possible to compress and fold the shield for transport, then deploy the shield for use. The shield can be attached to a spacecraft by use of snaps, hook-and-pile patches, or other devices. The shield can also contain multilayer insulation material, so that it provides some thermal protection in addition to mechanical protection.
Advocacy for Art Education: Beyond Tee-Shirts and Bumper Stickers
ERIC Educational Resources Information Center
Bobick, Bryna; DiCindio, Carissa
2012-01-01
Advocacy is not new to art education. Over the years, Goldfarb (1979), Hodsoll (1985), and Erickson and Young (1996) have written about the importance of arts advocacy, but the concept of advocacy has evolved with the times. For example, in the 1970s, arts advocacy was described as a "movement" and brought together art educators,…
32 CFR 636.10 - Hunter Army Airfield vehicle registration.
Code of Federal Regulations, 2011 CFR
2011-07-01
...) Temporary passes will be conspicuously placed on the left side of the vehicle dashboard between the... registered in one of two places: (1) Exterior, front windshield lower left corner. (2) Front, left bumper of... decal with the month on the left and the year on the right. (4) Decals will not be affixed to any other...
29 CFR 1910.179 - Overhead and gantry cranes.
Code of Federal Regulations, 2013 CFR
2013-07-01
... percent of rated load speed. (b) The bumper shall be so mounted that there is no direct shear on bolts... overstressed. (v) While any employee is on the load or hook, there shall be no hoisting, lowering, or traveling... tried out under no load. Extreme care shall be exercised; the block shall be “inched” into the limit or...
29 CFR 1910.179 - Overhead and gantry cranes.
Code of Federal Regulations, 2012 CFR
2012-07-01
... percent of rated load speed. (b) The bumper shall be so mounted that there is no direct shear on bolts... overstressed. (v) While any employee is on the load or hook, there shall be no hoisting, lowering, or traveling... tried out under no load. Extreme care shall be exercised; the block shall be “inched” into the limit or...
29 CFR 1910.179 - Overhead and gantry cranes.
Code of Federal Regulations, 2014 CFR
2014-07-01
... percent of rated load speed. (b) The bumper shall be so mounted that there is no direct shear on bolts... overstressed. (v) While any employee is on the load or hook, there shall be no hoisting, lowering, or traveling... tried out under no load. Extreme care shall be exercised; the block shall be “inched” into the limit or...
29 CFR 1910.179 - Overhead and gantry cranes.
Code of Federal Regulations, 2011 CFR
2011-07-01
... percent of rated load speed. (b) The bumper shall be so mounted that there is no direct shear on bolts... overstressed. (v) While any employee is on the load or hook, there shall be no hoisting, lowering, or traveling... tried out under no load. Extreme care shall be exercised; the block shall be “inched” into the limit or...
1981-03-01
Final Report: February 1978 ZAUTOMATIC OSCILLATING TURRET SYSTEM September 1980 * 6. PERFORMING 01G. REPORT NUMBER .J7. AUTHOR(S) S. CONTRACT OR GRANT...o....e.... *24 APPENDIX P-4 OSCILLATING BUMPER TURRET ...................... 25 A. DESCRIPTION 1. Turret Controls ...Other criteria requirements were: 1. Turret controls inside cab. 2. Automatic oscillation with fixed elevation to range from 20* below the horizontal to
49 CFR 591.9 - Petitions for remission or mitigation of forfeiture.
Code of Federal Regulations, 2010 CFR
2010-10-01
... VEHICLES AND EQUIPMENT SUBJECT TO FEDERAL SAFETY, BUMPER AND THEFT PREVENTION STANDARDS § 591.9 Petitions... forfeiture only if the motor vehicle has been imported pursuant to paragraph 591.5(f) and the condition not met relates to the compliance of a passenger motor vehicle with part 581 of this chapter. (b) A...
Former Autoworkers Resist Colleges' Call
ERIC Educational Resources Information Center
Ashburn, Elyse
2006-01-01
Since Jennifer L. Gigliotti was in elementary school, the 70-acre Ford Motor Company plant in northwestern Ohio has been a constant in her life. Her mother and father have worked the production line at the Maumee Stamping Plant for almost 60 years combined, making bumpers and body panels for generations of Ford vehicles. So when her father's name…
Youth Risk Taking Behavior: The Role of Schools. A Center Policy & Practice Analysis Brief
ERIC Educational Resources Information Center
Center for Mental Health in Schools at UCLA, 2007
2007-01-01
Risk taking is natural. As the bumper stickers says: "Risk taking happens!" Risk taking behavior may be beneficial or harmful. Some risk taking is unintentional. But a considerable amount stems from proactive or reactive motivation. For schools, some forms of student risk taking behavior are a necessity, and some forms are a problem. With respect…
Tapping in "to" Tapped Out: "Thinking about Conceptual Art"
ERIC Educational Resources Information Center
Lincoln, Kim; Stephens, Pam
2005-01-01
Perhaps one of the best ways to describe conceptual art is to quote an old bumper sticker, "If you like conceptual art, think about honking." Conceptual art is an art movement that came into prominence in the 1960s. Like other movements in modern art, conceptual art broke with established tradition. In conceptual art, ideas or perceptions are as…
Media Madness: With TV and the Internet Available 24/7, Can Libraries Compete?
ERIC Educational Resources Information Center
Jones, Jami
2004-01-01
Today's teens face an endless barrage of media--television, movies, radio, the Internet, magazines, and electronic games, not to mention those advertising slogans that shout out at them from billboards, bumper stickers, and even T-shirts. The sheer amount of time that teens spend with media is mind-boggling. Over the course of a year, young adults…
49 CFR Appendix A to Part 591 - Section 591.5(f) Bond for the Entry of a Single Vehicle
Code of Federal Regulations, 2010 CFR
2010-10-01
... VEHICLES AND EQUIPMENT SUBJECT TO FEDERAL SAFETY, BUMPER AND THEFT PREVENTION STANDARDS Pt. 591, App. A Appendix A to Part 591—Section 591.5(f) Bond for the Entry of a Single Vehicle Department of Transportation... Vehicle A Appendix A to Part 591 Transportation Other Regulations Relating to Transportation (Continued...
Development of a Vision-Based Robotic Follower Vehicle
2009-02-01
25 Figure 24: Determining the angles to the target...cable spooled out and the angle between the cable and the bumper to determine the range and bearing to a leader vehicle. To the author’s knowledge...Control Control of the pan/tilt angles can be modelled as a regulation problem, driving the angles to the target in the image to zero. However, the
49 CFR 567.4 - Requirements for manufacturers of motor vehicles.
Code of Federal Regulations, 2011 CFR
2011-10-01
..., or the door edge that meets the door-latch post, next to the driver's seating position, or if none of... applicable Federal motor vehicle safety, bumper, and theft prevention standards in effect on the date of... standards in effect on the date of manufacture shown above.” The expression “U.S.” or “U.S.A.” may be...
49 CFR 567.4 - Requirements for manufacturers of motor vehicles.
Code of Federal Regulations, 2012 CFR
2012-10-01
..., or the door edge that meets the door-latch post, next to the driver's seating position, or if none of... applicable Federal motor vehicle safety, bumper, and theft prevention standards in effect on the date of... standards in effect on the date of manufacture shown above.” The expression “U.S.” or “U.S.A.” may be...
49 CFR 567.4 - Requirements for manufacturers of motor vehicles.
Code of Federal Regulations, 2014 CFR
2014-10-01
..., or the door edge that meets the door-latch post, next to the driver's seating position, or if none of... applicable Federal motor vehicle safety, bumper, and theft prevention standards in effect on the date of... standards in effect on the date of manufacture shown above.” The expression “U.S.” or “U.S.A.” may be...
Capacitors Would Help Protect Against Hypervelocity Impacts
NASA Technical Reports Server (NTRS)
Edwards, David; Hubbs, Whitney; Hovater, Mary
2007-01-01
A proposal investigates alternatives to the present bumper method of protecting spacecraft against impacts of meteoroids and orbital debris. The proposed method is based on a British high-voltage-capacitance technique for protecting armored vehicles against shaped-charge warheads. A shield, according to the proposal, would include a bare metal outer layer separated by a gap from an inner metal layer covered with an electrically insulating material. The metal layers would constitute electrodes of a capacitor. A bias potential would be applied between the metal layers. A particle impinging at hypervelocity on the outer metal layer would break apart into a debris cloud that would penetrate the electrical insulation on the inner metal layer. The cloud would form a path along which electric current could flow between the metal layers, thereby causing the capacitor to discharge. With proper design, the discharge current would be large enough to vaporize the particles in the debris cloud to prevent penetration of the spacecraft. The shield design can be mass optimized to be competitive with existing bumper designs. Parametric studies were proposed to determine optimum correction between bias voltage, impacting particle velocity, gap space, and insulating material required to prevent spacecraft penetration.
Optimum structure of Whipple shield against hypervelocity impact
NASA Astrophysics Data System (ADS)
Lee, M.
2014-05-01
Hypervelocity impact of a spherical aluminum projectile onto two spaced aluminum plates (Whipple shield) was simulated to estimate an optimum structure. The Smooth Particle Hydrodynamics (SPH) code which has a unique migration scheme from a rectangular coordinate to an axisymmetic coordinate was used. The ratio of the front plate thickness to sphere diameter varied from 0.06 to 0.48. The impact velocities considered here were 6.7 km/s. This is the procedure we explored. To guarantee the early stage simulation, the shapes of debris clouds were first compared with the previous experimental pictures, indicating a good agreement. Next, the debris cloud expansion angle was predicted and it shows a maximum value of 23 degree for thickness ratio of front bumper to sphere diameter of 0.23. A critical sphere diameter causing failure of rear wall was also examined while keeping the total thickness of two plates constant. There exists an optimum thickness ratio of front bumper to rear wall, which is identified as a function of the size combination of the impacting body, front and rear plates. The debris cloud expansion-correlated-optimum thickness ratio study provides a good insight on the hypervelocity impact onto spaced target system.
The Bumper Boats Effect: Effect of Inertia on Self Propelled Active Particles Systems
NASA Astrophysics Data System (ADS)
Dai, Chengyu; Bruss, Isaac; Glotzer, Sharon
Active matter has been well studied using the standard Brownian dynamics model, which assumes that the self-propelled particles have no inertia. However, many examples of active systems, such as sub-millimeter bacteria and colloids, have non-negligible inertia. Using particle-based Langevin Dynamics simulation with HOOMD-blue, we study the role of particle inertia on the collective emergent behavior of self-propelled particles. We find that inertia hinders motility-induced phase separation. This is because the effective speed of particles is reduced due to particle-particle collisions-\\x9Dmuch like bumper boats, which take time to reach terminal velocity after a crash. We are able to fully account for this effect by tracking a particle's average rather than terminal velocity, allowing us to extend the standard Brownian dynamics model to account for the effects of momentum. This study aims to inform experimental systems where the inertia of the active particles is non-negligible. We acknowledge the funding support from the Center for Bio-Inspired Energy Science (CBES), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award # DE-SC0000989.
Assessing MMOD Impacts on Seal Performance
NASA Technical Reports Server (NTRS)
deGroh, Henry C., III; Daniels, C.; Dunlap, P.; Steinetz, B.
2007-01-01
The elastomer seal needed to seal in cabin air when NASA s Crew Exploration Vehicle is docked is exposed to space prior to docking. While open to space, the seal might be hit by orbital debris or meteoroids. The likelihood of damage of this type depends on the size of the particle. Our campaign is designed to find the smallest particle that will cause seal failure resulting in loss of mission. We will then be able to estimate environmental risks to the seal. Preliminary tests indicate seals can withstand a surprising amount of damage and still function. Collaborations with internal and external partners are in place and include seal leak testing, modeling of the space environment using a computer code known as BUMPER, and hypervelocity impact (HVI) studies at Caltech. Preliminary work at White Sands Test Facility showed a 0.5 mm diameter HVI damaged areas about 7 times that diameter, boring deep (5 mm) into elastomer specimens. BUMPER simulations indicate there is a 1 in 1440 chance of getting hit by a particle of diameter 0.08 cm for current Lunar missions; and 0.27 cm for a 10 year ISS LIDS seal area exposure.
Cooking Dinner at Home--From the Office
NASA Technical Reports Server (NTRS)
2005-01-01
It is well past quitting time, but you are still stuck in the office. Your spouse left work over an hour ago, but is caught in bumper-to-bumper traffic. As a result, neither of you were available to pick up your daughter on time from her soccer game. If your son hadn't gotten detention at school today, which also made him late for work, he could have picked her up. The next thing you know, it is already 8:30 at night, and your family members are finally all together under the same roof. No one has had a bite to eat since lunch, and dinner certainly isn't going to cook itself, or is it? For those who are all too familiar with this situation, it might be time to welcome the oven of the future into your homes: the ConnectIo Intelligent Oven, brought to you by TMIO, LLC, of Cleveland. Applying the same remote command and control concepts that NASA uses to run experiments on the International Space Station (ISS), ConnectIo allows its owners to cook dinner from the road, via a cell phone, personal digital assistant, or Internet connection.
Hynd, David; Depinet, Paul; Lorenz, Bernd
2013-01-01
The United Nations Economic Commission for Europe Informal Group on GTR No. 7 Phase 2 are working to define a build level for the BioRID II rear impact (whiplash) crash test dummy that ensures repeatable and reproducible performance in a test procedure that has been proposed for future legislation. This includes the specification of dummy hardware, as well as the development of comprehensive certification procedures for the dummy. This study evaluated whether the dummy build level and certification procedures deliver the desired level of repeatability and reproducibility. A custom-designed laboratory seat was made using the seat base, back, and head restraint from a production car seat to ensure a representative interface with the dummy. The seat back was reinforced for use in multiple tests and the recliner mechanism was replaced by an external spring-damper mechanism. A total of 65 tests were performed with 6 BioRID IIg dummies using the draft GTR No.7 sled pulse and seating procedure. All dummies were subject to the build, maintenance, and certification procedures defined by the Informal Group. The test condition was highly repeatable, with a very repeatable pulse, a well-controlled seat back response, and minimal observed degradation of seat foams. The results showed qualitatively reasonable repeatability and reproducibility for the upper torso and head accelerations, as well as for T1 Fx and upper neck Fx . However, reproducibility was not acceptable for T1 and upper neck Fz or for T1 and upper neck My . The Informal Group has not selected injury or seat assessment criteria for use with BioRID II, so it is not known whether these channels would be used in the regulation. However, the ramping-up behavior of the dummy showed poor reproducibility, which would be expected to affect the reproducibility of dummy measurements in general. Pelvis and spine characteristics were found to significantly influence the dummy measurements for which poor reproducibility was observed. It was also observed that the primary neck response in these tests was flexion, not extension. This correlates well with recent findings from Japan and the United States showing a correlation between neck flexion and injury in accident replication simulations and postmortem human subjects (PMHS) studies, respectively. The present certification tests may not adequately control front cervical spine bumper characteristics, which are important for neck flexion response. The certification sled test also does not include the pelvis and so cannot be used to control pelvis response and does not substantially load the lumbar bumpers and so does not control these parts of the dummy. The stiffness of all spine bumpers and of the pelvis flesh should be much more tightly controlled. It is recommended that a method for certifying the front cervical bumpers should be developed. Recommendations are also made for tighter tolerance on the input parameters for the existing certification tests.
NASA Astrophysics Data System (ADS)
Kessler, D. J.
What is currently known about the orbital debris flux is from a combination of ground based and in-space measurements. These measurements have revealed an increasing population with decreasing size. A summary of measurements is presented for the following sources: the North American Aerospace Defense Command Catalog, the Perimeter Acquisition and Attack Characterization System Radar, ground based optical telescopes, the Explorer 46 Meteoroid Bumper Experiment, spacecraft windows, and Solar Max surfaces.
NASA Technical Reports Server (NTRS)
Kessler, D. J.
1986-01-01
What is currently known about the orbital debris flux is from a combination of ground based and in-space measurements. These measurements have revealed an increasing population with decreasing size. A summary of measurements is presented for the following sources: the North American Aerospace Defense Command Catalog, the Perimeter Acquisition and Attack Characterization System Radar, ground based optical telescopes, the Explorer 46 Meteoroid Bumper Experiment, spacecraft windows, and Solar Max surfaces.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-25
... used as a basis for the non-automatic suspension of an RI registration, deletes redundant text from... Part 592 as a Basis for the Non-Automatic Suspension or Revocation of an RI Registration B. Deletion of... violations of the regulations in part 592 as a basis for the non-automatic suspension or revocation of an RI...
Student and Faculty Perceptions of Plus/Minus Grading and Its Effect on Course Grade Point Averages
ERIC Educational Resources Information Center
Edgar, Leslie D.; Johnson, Donald M.; Graham, Donna L.; Dixon, Bruce L.
2014-01-01
In fall 2005, the Dale Bumpers College of Agricultural, Food and Life Sciences at the University of Arkansas authorized the optional use of a plus/minus grading system. Since 2005, approximately one-half of courses have been graded using plus/minus and one-half using the straight letter grade system. This study examined student (n = 338) and…
FTIR Analyses of Hypervelocity Impact Deposits: DebriSat Tests
2015-03-27
Aerospace Concept Design Center advised on selection of materials for various subsystems. • Test chamber lined with “soft catch” foam panels to trap...C-0001 Authorized by: Space Systems Group Distribution Statement A: Approved for public release; distribution unlimited Report...Pre Preshot target was a multi-shock shield supplied by NASA designed to catch the projectile. It consisted of seven bumper panels consisting of
Shortleaf pine seed production in natural stands in the Ouachita and Ozark mountains
Michael G. Shelton; Robert F. Wittwer
1996-01-01
Seed production of shortleaf pine (Pinus echinata Mill.) was monitored from 1965 to 1974 to determine the periodicity qf seed crops in both woods-run stands and seed-production areas. One bumper and two good seed crops occurred during the 9-yr period. The two largest crops occurred in successive years, then seed production was low for 4 yr before...
Physics of debris clouds from hypervelocity impacts
NASA Technical Reports Server (NTRS)
Zee, Ralph
1993-01-01
The protection scheme developed for long duration space platforms relies primarily upon placing thin metal plates or 'bumpers' around flight critical components. The effectiveness of this system is highly dependent upon its ability to break up and redistribute the momentum of any particle which might otherwise strike the outer surface of the spacecraft. Therefore it is of critical importance to design the bumpers such that maximum dispersion of momentum is achieved. This report is devoted to an in-depth study into the design and development of a laboratory instrument which would permit the in-situ monitoring of the momentum distribution as the impact event occurs. A series of four designs were developed, constructed and tested culminating with the working instrument which is currently in use. Each design was individually tested using the Space Environmental Effects Facility (SEEF) at the Marshall Space Flight Center in Huntsville, Alabama. Along with the development of the device, an experimental procedure was developed to assist in the investigation of various bumper materials and designs at the SEEF. Preliminary results were used to compute data which otherwise were not experimentally obtainable. These results were shown to be in relative agreement with previously obtained values derived through other methods. The results of this investigation indicated that momentum distribution could in fact be measured in-situ as the impact event occurred thus giving a more accurate determination of the effects of experimental parameters on the momentum spread. Data produced by the instrument indicated a Gaussian-type momentum distribution. A second apparatus was developed and it was placed before the shield in the line of travel utilized a plate to collect impact debris scattered backwards. This plate had a passage hole in the center to allow the particle to travel through it and impact the proposed shield material. Applying the law of conservation of angular momentum a backward momentum vector was determined from the angular velocity of the plate. The forward scattered and backward scattered momentum values were then analyzed to judge the distribution of debris. Loss of momentum was attributed to the inaccuracies of the means of measurement. Assumptions of symmetrical debris for the forward and backward scattered directions also contributed to this loss.
Viewport concept for space station modules
NASA Technical Reports Server (NTRS)
Douglas, F., III
1986-01-01
The generic design of a 20-in. diameter viewport for the space station modules is discussed. It should possess the capabilities of meteoroid/debris protection (with no metallic cover), redundancies in its meteoroid/debris protection, and pressure sealing systems. In addition, it should provide ease of change out for maintenance or repair. The design does not take into account the bumper-shield effect of the outermost panes in the meteoroid/debris analysis.
NASA Technical Reports Server (NTRS)
Christiansen, Eric L. (Inventor); Crews, Jeanne L. (Inventor)
2005-01-01
Flexible multi-shock shield system and method are disclosed for defending against hypervelocity particles. The flexible multi-shock shield system and method may include a number of flexible bumpers or shield layers spaced apart by one or more resilient support layers, all of which may be encapsulated in a protective cover. Fasteners associated with the protective cover allow the flexible multi-shock shield to be secured to the surface of a structure to be protected.
Robert F. Wittwer; Micahel G. Shelton; James M. Guldin
2003-01-01
Shortleaf pine (Pinus echinata Mill.) seed production was monitored for 4 yr in stands harvested by a range of even- and uneven-aged reproduction cutting methods. The fifty-two 35â40 ac stands were distributed throughout the Ouachita Mountains from central Arkansas to eastern Oklahoma. Seed crops were characterized as good, poor, poor, and bumper,...
Fort Leonard Wood German POW Stonework: Maintenance and Repair
2017-07-01
powered chisels, scaler (power chipper), and thin diamond- bladed grinders should be approved by architect or project manager. All work should be...Figure 5. Deteriorated mortar and plant growth on the patio of Garlington House. Photo NCPTT 8 • Raising mower blades to avoid low-ly- ing features...protective perimeter around features, attaching protective bumpers to the lawn mower, raising mower blades to avoid low-lying features, and using smaller
System Engineering Analysis of Topside Cranes Installed on AD, AR, and AS Class Ships
1982-02-06
4 severity CASREPs. Water or moisture in oumzs or motors accounted for five CASREPs; moisture in a transformer caused a class C fire , which resulted...Components of Bridge Cranes, Monorail Hoist Systems, and Side Port Hoists Associated Equipment: Accumulators Ladders Speed reducers Brakes Load blocks...Switches Bridge Locking devices *Tow bars Bumpers * Monorails Tracks Collector assembly Motors (electrical *Trolley buses Controller and hydraulic) *Trolleys
ERIC Educational Resources Information Center
Patterson, Jerry; Kelleher, Paul
2005-01-01
School leaders remember the good old days when resources were adequate, school boards were stable, superintendents stayed a while, and forces outside the school district trusted those inside the school district to do the best job possible educating students. It used to be such smooth sailing! Whether this version of history is fact, illusion or…
JPRS Report, China 1989 Selected Provincial Economic Reports
1989-08-23
bumper harvest, and the supply of grain and the main nonstaple foods continued to increase. Upon implementing the responsibility system of linking...grain production topped 2,346,000 tons, surpassing the plan by 24,600 tons. Output of all of the main nonstaple foods exceeded the plan. Seeding...1988 were mainly urban infrastructure construction projects, such as the Fuxingmen to Bawangfen Subway and the Gaobeidian Sewage Treatment Plant
Seed dissemination in small clearcuttings in north-central California
Philip M. McDonald
1980-01-01
In a 1964-1967 study on the Challenge Experimental Forest, seedfall was evaluated in 2-, 5-, and 10-acre circular clearcuttings. During the 4 years, 10 seed crops, ranging from light to bumper, were produced by ponderosa pine. white fir, Douglas-fir, and incense cedar. Seedfall ranged from 76 to 40,691 sound seed per acre (188 to lOO,547/ha) for a single species in a...
Analysis of Energy-Absorbing Foundations.
1978-12-15
side rails. At the top of the rebound, air brakes are automatically activated which press against the rails and stop the table, preventing a second...for the same application to automobile bumpers , was greater than that used in an alternate design in which the tube was crushed axially, so it appears...shock mounts prepared by Burns [48]. Typi- cal non-linear, elastic, load-deflection curves are given for helical springs, pneumatic cylinders, hydraulic
On projectile fragmentation at high-velocity perforation of a thin bumper
NASA Astrophysics Data System (ADS)
Myagkov, N. N.; Stepanov, V. V.
2014-09-01
By means of 3D numerical simulations, we study the statistical properties of the fragments cloud formed during high-velocity impact of a spherical projectile on a mesh bumper. We present a quantitative description of the projectile fragmentation, and study the nature of the transition from the damage to the fragmentation of the projectile when the impact velocity varies. A distinctive feature of the present work is that the calculations are carried out by smoothed particle hydrodynamics (SPH) method applied to the equations of mechanics of deformable solids (MDS). We describe the materials behavior by the Mie-Grüneisen equation of state and the Johnson-Cook model for the yield strength. The maximum principal stress spall model is used as the fracture model. It is shown that the simulation results of fragmentation based on the MDS equations by the SPH method are qualitatively consistent with the results obtained earlier on the basis of the molecular dynamics and discrete element models. It is found that the power-law distribution exponent does not depend on energy imparted to the projectile during the high-velocity impact. At the same time, our calculations show that the critical impact velocity, the power-law exponent and other critical exponents depend on the fracture criterion.
Studies about the Behavior of the Crash Boxes of a Car Body
NASA Astrophysics Data System (ADS)
Constantin, B. A.; Iozsa, D.; Fratila, G.
2016-11-01
A continuous evolution of requirements and standards sheds over the development of new vehicles (for example EuroNCAP ratings) in order to create competition between same market models customer related. The low speed impact protection has to be permanently improved as the damage of the front end structure of the vehicle to be reduced to minimal. As a consequence, a lower damage implies less repair costs and therefore a lower insurance category. The front end structure, including the bumper, responds for the absorption of the kinetic energy created during the impact with maximum efficiency in order to avoid the large deformation of structural components. This is only one of the constraints that the front end structure has to cope with, additionally we can mention the dimensioning of the front end of the vehicle which can affect the packaging, which is mainly influenced by the design, styling and the pedestrian requirements intended to be accomplished by the vehicle. The present paper focuses on the low speed urban impact, offering an overview over the actual state, the load configuration, the applicable regulation, the challenging requirements of a modern front structure, which the modern bumper has to comply with and the finite element simulation of this kind of test.
Characterization of the Protein Crystal Growth Apparatus for Microgravity Aboard the Space Station
NASA Technical Reports Server (NTRS)
Kundrot, Craig E.; Roeber, D.; Achari, A.; Stinson, Thomas N. (Technical Monitor)
2002-01-01
We have conducted experiments to determine the equilibration rates of some major precipitants used in protein crystallography aboard the International Space Station (ISS). The solutions were placed in the Protein Crystallization Apparatus for Microgravity (PCAM) which mimic Cryschem sitting drop trays. The trays were placed in cylinders. These cylinders were placed inside a Single locker Thermal Enclosure System (STES), and were activated for different durations during the flight. Bumpers pressed against elastomers seal drops in a deactivated state during pre-flight and prior to transfer to the ISS. Activation occurs while in flight on the ISS by releasing the bumpers allowing the drops to be exposed to the reservoir. PCAM was flown to the ISS on STS 100, Flight 6A, on April 19, 2001. Six series of equilibration experiments were tested for each precipitant with a small amount of Green Fluorescent Protein (GFP). Cylinder 10 was never activated, 7 was activated for 40 days, 8 was activated for 20 days, 9 was activated for 10 days, 11 was activated for 4 days and 12 was activated for 2 days. Upon the return to Earth by STS 104 on July 24,2001 the samples were transferred to Marshall Space Flight Center. The samples were then brought to the lab and the volumes of each sample were measured.
Vessel structural support system
Jenko, James X.; Ott, Howard L.; Wilson, Robert M.; Wepfer, Robert M.
1992-01-01
Vessel structural support system for laterally and vertically supporting a vessel, such as a nuclear steam generator having an exterior bottom surface and a side surface thereon. The system includes a bracket connected to the bottom surface. A support column is pivotally connected to the bracket for vertically supporting the steam generator. The system also includes a base pad assembly connected pivotally to the support column for supporting the support column and the steam generator. The base pad assembly, which is capable of being brought to a level position by turning leveling nuts, is anchored to a floor. The system further includes a male key member attached to the side surface of the steam generator and a female stop member attached to an adjacent wall. The male key member and the female stop member coact to laterally support the steam generator. Moreover, the system includes a snubber assembly connected to the side surface of the steam generator and also attached to the adjacent wall for dampening lateral movement of the steam generator. In addition, the system includes a restraining member of "flat" attached to the side surface of the steam generator and a bumper attached to the adjacent wall. The flat and the bumper coact to further laterally support the steam generator.
Analytic Ballistic Performance Model of Whipple Shields
NASA Technical Reports Server (NTRS)
Miller, J. E.; Bjorkman, M. D.; Christiansen, E. L.; Ryan, S. J.
2014-01-01
The dual-wall Whipple shield is the shield of choice for lightweight, long-duration flight. The shield uses an initial sacrificial wall to initiate fragmentation and melt an impacting threat that expands over a void before hitting a subsequent shield wall of a critical component. The key parameters to this type of shield are the rear wall and its mass which stops the debris, as well as the minimum pressure generated under threat particle impact of the sacrificial wall and the amount of void that is available for expansion. Ensuring the minimum pressure is sufficiently high to achieve large scale fragmentation/melt of the threat particle enables the expansion of the threat and reduces the momentum flux of the debris on the rear wall. Three key factors in the minimum pressure achieved are the thickness of the sacrificial wall relative to the characteristic dimension of the impacting particle, the density and material cohesion contrast of the sacrificial wall relative to the threat particle and the impact speed. The mass of the rear wall and the sacrificial wall are desirable to minimize for launch costs and dynamic concerns making it important to have an understanding of the effects of density contrast and impact speed. In this paper a fourth key parameter is identified related to fragmentation, which corresponds to the ratio of the size of the projectile relative to the transition from brittle to ductile hole growth in the projectile. Ballistic limit equations have been developed to define the failure limits of a MMOD shield, generally in terms of projectile diameter (or mass), impact velocity, and angle. Within the range of impact velocities relevant for Earth-orbiting spacecraft, three distinct regions of penetration phenomenology have been identified for Whipple shields: center dot Low velocity: the projectile is eroded (and possibly deformed) during its passage through the bumper plate, but is not fragmented. Thus, perforation of the rear wall is by a fragment with a mass and speed equal to or less than the original impactor. center dot Intermediate (shatter) velocity: impact velocities are sufficient to induce projectile fragmentation upon impact with the bumper plate, resulting in a coarse debris cloud with large solid fragments. Increasing velocity within the shatter regime results in increased fragmentation, and eventually melting, of the projectile and bumper fragments, generating a finer and more evenly dispersed debris cloud. Failure of the rear wall is a complicated combination of modes observed at low- and hypervelocity. center dot Hypervelocity: the projectile and holed-out bumper material is completely, or nearly completely, melted and/or vaporized by the initial impact. The resultant debris cloud impacts over a dispersed area of the rear wall, loading it impulsively and inducing failure through rupture or petalling. While each of these regimes are well observed with extensive empirical methods to describe these regions, differences in impactor materials, configurations of shields and questions about the limitations of the attainable impact speeds have left questions that are difficult to answer from completely empirical methods.
Multiple-foil microabrasion package (A0023)
NASA Technical Reports Server (NTRS)
Mcdonnell, J. A. M.; Ashworth, D. G.; Carey, W. C.; Flavill, R. P.; Jennison, R. C.
1984-01-01
The specific scientific objectives of this experiment are to measure the spatial distribution, size, velocity, radiance, and composition of microparticles in near-Earth space. The technological objectives are to measure erosion rates resulting from microparticle impacts and to evaluate thin-foil meteor 'bumpers'. The combinations of sensitivity and reliability in this experiment will provide up to 1000 impacts per month for laboratory analysis and will extend current sensitivity limits by 5 orders of magnitude in mass.
Anti-Access/Area Denial: Time To Ditch the Bumper Sticker?
2013-05-20
since the fall of the Soviet Union. Several nations, particularly China, are rapidly becoming capable of challenging the status quo. This fact... economic modernization for at least the coming fifty years. 2 However, that view later changed rapidly. “The revolution in air-delivered weapons...attempted to take Constantinople . 10 The ends were that the Turks denied the enemy access to the waters near their city. The means were the use of the
Hypervelocity impact simulations of Whipple shields
NASA Technical Reports Server (NTRS)
Segletes, Steven B.; Zukas, Jonas A.
1992-01-01
The problem associated with protecting space vehicles from space debris impact is described. Numerical simulation is espoused as a useful complement to experimentation: as a means to help understand and describe the hypervelocity impact phenomena. The capabilities of a PC-based hydrocode, ZeuS, are described, for application to the problem of hypervelocity impact. Finally, results of ZeuS simulations, as applied to the problem of bumper shield impact, are presented and compared with experimental results.
2000-07-15
At the 50th anniversary gala that capped a year-long celebration of 50 years of rocket launches from Cape Canaveral Air Force Station, gala chairman Ed Gormel (left) presents a plaque to Capt. Harry Sheffield, Commander, Naval Ordnance Test Unit, Cape Canaveral. The first launch at CCAFS took place at 9:28 a.m. on July 24, 1950, with the liftoff of Bumper 8 from Launch Complex 3. The gala was hosted by the Cape Canaveral Chapter Air Force Association
2000-07-15
At the 50th anniversary gala that capped a year-long celebration of 50 years of rocket launches from Cape Canaveral Air Force Station, gala chairman Ed Gormel (left) presents a plaque to Capt. Harry Sheffield, Commander, Naval Ordnance Test Unit, Cape Canaveral. The first launch at CCAFS took place at 9:28 a.m. on July 24, 1950, with the liftoff of Bumper 8 from Launch Complex 3. The gala was hosted by the Cape Canaveral Chapter Air Force Association
External tank space debris considerations
NASA Technical Reports Server (NTRS)
Elfer, N.; Baillif, F.; Robinson, J.
1992-01-01
Orbital debris issues associated with maintaining a Space Shuttle External Tank (ET) on orbit are presented. The first issue is to ensure that the ET does not become a danger to other spacecraft by generating space debris, and the second is to protect the pressurized ET from penetration by space debris or meteoroids. Tests on shield designs for penetration resistance showed that when utilized with an adequate bumper, thermal protection system foam on the ET is effective in preventing penetration.
Autonomous mobile robot for radiologic surveys
Dudar, A.M.; Wagner, D.G.; Teese, G.D.
1994-06-28
An apparatus is described for conducting radiologic surveys. The apparatus comprises in the main a robot capable of following a preprogrammed path through an area, a radiation monitor adapted to receive input from a radiation detector assembly, ultrasonic transducers for navigation and collision avoidance, and an on-board computer system including an integrator for interfacing the radiation monitor and the robot. Front and rear bumpers are attached to the robot by bumper mounts. The robot may be equipped with memory boards for the collection and storage of radiation survey information. The on-board computer system is connected to a remote host computer via a UHF radio link. The apparatus is powered by a rechargeable 24-volt DC battery, and is stored at a docking station when not in use and/or for recharging. A remote host computer contains a stored database defining paths between points in the area where the robot is to operate, including but not limited to the locations of walls, doors, stationary furniture and equipment, and sonic markers if used. When a program consisting of a series of paths is downloaded to the on-board computer system, the robot conducts a floor survey autonomously at any preselected rate. When the radiation monitor detects contamination, the robot resurveys the area at reduced speed and resumes its preprogrammed path if the contamination is not confirmed. If the contamination is confirmed, the robot stops and sounds an alarm. 5 figures.
Autonomous mobile robot for radiologic surveys
Dudar, Aed M.; Wagner, David G.; Teese, Gregory D.
1994-01-01
An apparatus for conducting radiologic surveys. The apparatus comprises in the main a robot capable of following a preprogrammed path through an area, a radiation monitor adapted to receive input from a radiation detector assembly, ultrasonic transducers for navigation and collision avoidance, and an on-board computer system including an integrator for interfacing the radiation monitor and the robot. Front and rear bumpers are attached to the robot by bumper mounts. The robot may be equipped with memory boards for the collection and storage of radiation survey information. The on-board computer system is connected to a remote host computer via a UHF radio link. The apparatus is powered by a rechargeable 24-volt DC battery, and is stored at a docking station when not in use and/or for recharging. A remote host computer contains a stored database defining paths between points in the area where the robot is to operate, including but not limited to the locations of walls, doors, stationary furniture and equipment, and sonic markers if used. When a program consisting of a series of paths is downloaded to the on-board computer system, the robot conducts a floor survey autonomously at any preselected rate. When the radiation monitor detects contamination, the robot resurveys the area at reduced speed and resumes its preprogrammed path if the contamination is not confirmed. If the contamination is confirmed, the robot stops and sounds an alarm.
Safety assessment characteristics of pedestrian legform impactors in vehicle-front impact tests.
Matsui, Yasuhiro
2014-12-01
This study investigated the characteristics of safety assessment results of front-area vehicle impact tests carried out using the Transport Research Laboratory (TRL) legform impactor and a flexible legform impactor (FLEX legform impactor). Different types of vehicles (sedan, sport utility vehicle, high-roof K-car, and light cargo van) were examined. The impact locations in the study were the center of the bumper and an extremely stiff structure of the bumper (i.e., in front of the side member) of each tested vehicle. The measured injury criteria were normalized by injury assessment reference values of each legform impactor. The test results for center and side-member impacts indicated that there were no significant differences in ligament injury assessments derived from the normalized knee ligament injury measures between the TRL legform impactor and the FLEX legform impactor. Evaluations made using the TRL legform impactor and the FLEX legform impactor are thus similar in the vehicle safety investigation for knee ligament injury. Vehicle-center impact test results revealed that the tibia fracture assessments derived from the normalized tibia fracture measures did not significantly differ between the TRL legform impactor and the FLEX legform impactor. However, for an impact against an extremely stiff structure, there was a difference in the tibia fracture assessment between the FLEX legform impactor and the TRL legform impactor owing to their different sensor types. Copyright © 2014 Elsevier Ltd. All rights reserved.
Second molar impaction associated with lip bumper therapy
Jacob, Helder Baldi; LeMert, Shawn; Alexander, Richard G.; Buschang, Peter H.
2014-01-01
INTRODUCTION: Although lip bumpers (LBs) provide significant clinical gain of mandibular arch perimeter in mixed-dentition patients, orthodontists are reluctant to use them due to the possibility of permanent second molar eruptive disturbances. OBJECTIVE: The present study was conducted to assess second molar impaction associated with the use of LBs, and to investigate how they can be solved. MATERIAL AND METHODS: Lateral and panoramic radiographs of 67 patients (34 females and 33 males) were assessed prior (T1) and post-LB treatment (T2). LB therapy lasted for approximately 1.8 ± 0.9 years. Concomitant rapid palatal expansion (RPE) was performed in the maxilla at LB treatment onset. Impaction of mandibular second molars was assessed by means of panoramic radiographs in relation to the position of first mandibular molars. Horizontal and vertical movements of first and second molars were assessed cephalometrically on lateral cephalometric radiographs based on mandibular superimpositions. RESULTS: Eight (11.9%) patients had impacted second molars at the end of LB therapy. Two patients required surgical correction, whereas five required spacers and one patient was self-corrected. Mandibular first molar tip and apex migrated forward 1.3 mm and 2.3 mm, respectively. Second molar tip showed no statistically significant horizontal movement. CONCLUSION: Although LB therapy increased the risk of second molar impaction, impactions were, in most instances, easily solved. PMID:25628086
Multimaterial lamination as a means of retarding penetration and spallation failures in plates
NASA Technical Reports Server (NTRS)
Dibattista, J. D.; Humes, D. H.
1972-01-01
Experimental data are presented which show that hypervelocity impact spallation and penetration failures of a single solid aluminum plate and of a solid aluminum plate spaced a distance behind a Whipple meteor bumper may be retarded by replacing the solid aluminum plate with a laminated plate. Four sets of experiments were conducted. The first set of experiments was conducted with projectile mass and velocity held constant and with polycarbonate cylinders impacted into single plates of different construction. The second set of experiments was done with single plates of various construction and aluminum spherical projectiles of similar mass but different velocities. These two experiments showed that a laminated plate of aluminum and polycarbonate or aluminum and methyl methacrylate could prevent spallation and penetration failures with a lower areal density than either an all-aluminum laminated plate or a solid aluminum plate. The aluminum laminated plate was in turn superior to the solid aluminum plate in resisting spallation and penetration failures. In addition, through an example of 6061-T6 aluminum and methyl methacrylate, it is shown that a laminated structure ballistically superior to its parent materials may be built. The last two sets of experiments were conducted using bumper-protected main walls of solid aluminum and of laminated aluminum and polycarbonate. Again, under hypervelocity impact conditions, the laminated main walls were superior to the solid aluminum main walls in retarding spallation and penetration failures.
Reducing Latin America’s Bumper Crop: Babies.
birth control measures. Data was gathered using a literature search which relied heavily on periodicals and materials written as a result of on site research in Latin America by the American Universities Field Staff. The high birth rate in Latin America is caused primarily either by the prohibitions of the Catholic Church against artifical contraceptive methods nor by cultural attitudes towards large families. High birth rates are caused primarily by poverty, illiteracy, and underdevelopment. Where socioechnomic conditions have improved in Latin America birth rates have
1994-04-07
detector mated to wide- angle optics to continuously view a large conical volume of space in the vicinity of the orbiting spacecraft . When a debris... large uncertainties. This lack of reliable data for debris particles in the millimeter/centimeter size range presents a problem to spacecraft designers...by smaller particles (<I mm) can be negated by the use of meteor bumpers covering the critical parts of a spacecraft , without incurring too large a
Phenomena after meteoroid penetration of a bumper plate
NASA Technical Reports Server (NTRS)
Todd, F. C.
1971-01-01
The analysis of hypervelocity impact of particles on a detector in space, with flow and shock penetration through fluid, plastic, and elastic zones was studied. The original paper and computer program on this topic is presented. Improvements in the program for the study of the formation of a cone of debris are discussed. The truncated apex of the cone is at the hole formed by the penetration of an initially spherical rock through a thin plate. A solution for the penetration of the thin plate was sought.
NASA Technical Reports Server (NTRS)
Goldowskiy, M. P.
1984-01-01
A self regulating, nonfrictional, active magnetic bearing is disclosed which has an elongated cylindrical housing for containing a shaft type armature with quadrature positioned shaft position sensors and equidistantly positioned electromagnets located at one end of the housing. Each set of sensors is responsive to orthogonal displacement of the armature and is used to generate control signals to energize the electromagnets to center the armature. A bumper magnet assembly is located at one end of the housing for dampening any undesired axial movement of the armature or to axially move the armature either continuously or fixedly.
ERIC Educational Resources Information Center
Congress of the U.S., Washington, DC. Senate Committee on Small Business.
The text of a Senate Committee on Small Business hearing on the cost and availability of liability insurance for small business is presented in this document. The crisis faced by small business with skyrocketing insurance rates is described in statements by Senators Lowell Weicker, Jr., Robert Kasten, Jr., Dale Bumpers, Paul Trible, Jr., James…
MUVES-S2 Adaptive Geometry User Guide
2015-09-01
wheeled vehicle (HMMWV) with gunner protection kit ( GPK ) and 4 doors would have 6 top-level groups: • HMMWV (0 mm, 0 mm, 0 mm): front bumper centerline...on ground plane • GPK (–1,400 mm, 0 mm, 0 mm): rotate about Z axis center on turret ring • Front_left_door (–1,200 mm, 1,142.7 mm, 0 mm): rotate...an analysis which included opening and closing all doors and slewing the GPK the readme file would read as such: • HMMWV (0mm, 0mm, 0mm): front
1982-11-15
Metca) for each ring 6 Aluminum orirlce end ring 15 Rubber bumpers 7 Back plate inner boot ring 16 Castor oil rill-fluid I ’)-ring %eals I ’ Nikel ...electrode .ab% with hook-up wire -ig. 6 - Sectional v-icw orf ISRI) typc (662 tran.dhcer 9 YOUNG, TIMS. AND HENRIQUFZ 0.42 m. Approximately 85% of the...electrical leads for each ring are routed to individual bulkhead connectors on the trans- ducer back plate with high-voltage silicone-jacketed hookup wire
If we're not merging for for the people, why bother?
Gonzalez, W G
2001-01-01
When Batts Inc., a family business that invented wooden clothes hangers in 1903 was sold to Tyco International, it's ardent competitor, in 1999, nobody bothered to tell its 500 loyal employees in Holland that the plants would be closed, their jobs--perhaps entire careers--ended. And when Lescoa, a family-owned, auto-accessory manufacturing company in west Michigan since 1945, was combined with American Bumper, it's competitor from Ionia, the pledge to "not take the company apart" was communicated. However, that pledge was quickly forgotten as American's executives took over, ignoring the family-styled people-culture of decades past.
Optimization techniques applied to passive measures for in-orbit spacecraft survivability
NASA Technical Reports Server (NTRS)
Mog, Robert A.; Helba, Michael J.; Hill, Janeil B.
1992-01-01
The purpose of this research is to provide Space Station Freedom protective structures design insight through the coupling of design/material requirements, hypervelocity impact phenomenology, meteoroid and space debris environment sensitivities, optimization techniques and operations research strategies, and mission scenarios. The goals of the research are: (1) to develop a Monte Carlo simulation tool which will provide top level insight for Space Station protective structures designers; (2) to develop advanced shielding concepts relevant to Space Station Freedom using unique multiple bumper approaches; and (3) to investigate projectile shape effects on protective structures design.
Device for coupling a first vehicle to a second vehicle
NASA Technical Reports Server (NTRS)
Rudmann, A. A. (Inventor)
1980-01-01
A device is disclosed, carried by a first vehicle such as an orbiting space shuttle, having a plurality of contact members for engaging and holding an annular ring on a second vehicle such as an orbiting payload. The contact members are connected to manipulator arms which are mounted at a fulcrum point and which are moved by an iris type mechanism. Movement of the manipulator arms causes the contact members to grasp or release the annular ring. Bumper devices are provided to axially align the annular ring and draw the contact members into engagement therewith.
Orbital Debris Research in the United States
NASA Technical Reports Server (NTRS)
Stansbery, Gene
2009-01-01
The presentation includes information about growth of the satellite population, the U.S. Space Surveillance Network, tracking and catalog maintenance, Haystack and HAX radar observation, Goldstone radar, the Michigan Orbital Debris Survey Telescope (MODEST), spacecraft surface examinations and sample of space shuttle impacts. GEO/LEO observations from Kwajalein Atoll, NASA s Orbital Debris Engineering Model (ORDEM2008), a LEO-to-GEO Environment Debris Model (LEGEND), Debris Assessment Software (DAS) 2.0, the NASA/JSC BUMPER-II meteoroid/debris threat assessment code, satellite reentry risk assessment, optical size and shape determination, work on more complicated fragments, and spectral studies.
NASA Technical Reports Server (NTRS)
1996-01-01
Heat Pipes were originally developed by NASA and the Los Alamos Scientific Laboratory during the 1960s to dissipate excessive heat build- up in critical areas of spacecraft and maintain even temperatures of satellites. Heat pipes are tubular devices where a working fluid alternately evaporates and condenses, transferring heat from one region of the tube to another. KONA Corporation refined and applied the same technology to solve complex heating requirements of hot runner systems in injection molds. KONA Hot Runner Systems are used throughout the plastics industry for products ranging in size from tiny medical devices to large single cavity automobile bumpers and instrument panels.
Honeycomb vs. Foam: Evaluating Potential Upgrades to ISS Module Shielding
NASA Technical Reports Server (NTRS)
Ryan, Shannon J.; Christiansen, Eric L.
2009-01-01
The presence of honeycomb cells in a dual-wall structure is advantageous for mechanical performance and low weight in spacecraft primary structures but detrimental for shielding against impact of micrometeoroid and orbital debris particles (MMOD). The presence of honeycomb cell walls acts to restrict the expansion of projectile and bumper fragments, resulting in the impact of a more concentrated (and thus lethal) fragment cloud upon the shield rear wall. The Multipurpose Laboratory Module (MLM) is a Russian research module scheduled for launch and ISS assembly in 2011 (currently under review). Baseline shielding of the MLM is expected to be predominantly similar to that of the existing Functional Energy Block (FGB), utilizing a baseline triple wall configuration with honeycomb sandwich panels for the dual bumpers and a thick monolithic aluminum pressure wall. The MLM module is to be docked to the nadir port of the Zvezda service module and, as such, is subject to higher debris flux than the FGB module (which is aligned along the ISS flight vector). Without upgrades to inherited shielding, the MLM penetration risk is expected to be significantly higher than that of the FGB module. Open-cell foam represents a promising alternative to honeycomb as a sandwich panel core material in spacecraft primary structures as it provides comparable mechanical performance with a minimal increase in weight while avoiding structural features (i.e. channeling cells) detrimental to MMOD shielding performance. In this study, the effect of replacing honeycomb sandwich panel structures with metallic open-cell foam structures on MMOD shielding performance is assessed for an MLM-representative configuration. A number of hypervelocity impact tests have been performed on both the baseline honeycomb configuration and upgraded foam configuration, and differences in target damage, failure limits, and derived ballistic limit equations are discussed.
NASA Technical Reports Server (NTRS)
Jolly, William H.
1992-01-01
Relationships defining the ballistic limit of Space Station Freedom's (SSF) dual wall protection systems have been determined. These functions were regressed from empirical data found in Marshall Space Flight Center's (MSFC) Hypervelocity Impact Testing Summary (HITS) for the velocity range between three and seven kilometers per second. A stepwise linear least squares regression was used to determine the coefficients of several expressions that define a ballistic limit surface. Using statistical significance indicators and graphical comparisons to other limit curves, a final set of expressions is recommended for potential use in Probability of No Critical Flaw (PNCF) calculations for Space Station. The three equations listed below represent the mean curves for normal, 45 degree, and 65 degree obliquity ballistic limits, respectively, for a dual wall protection system consisting of a thin 6061-T6 aluminum bumper spaced 4.0 inches from a .125 inches thick 2219-T87 rear wall with multiple layer thermal insulation installed between the two walls. Normal obliquity is d(sub c) = 1.0514 v(exp 0.2983 t(sub 1)(exp 0.5228). Forty-five degree obliquity is d(sub c) = 0.8591 v(exp 0.0428) t(sub 1)(exp 0.2063). Sixty-five degree obliquity is d(sub c) = 0.2824 v(exp 0.1986) t(sub 1)(exp -0.3874). Plots of these curves are provided. A sensitivity study on the effects of using these new equations in the probability of no critical flaw analysis indicated a negligible increase in the performance of the dual wall protection system for SSF over the current baseline. The magnitude of the increase was 0.17 percent over 25 years on the MB-7 configuration run with the Bumper II program code.
A Field Data Analysis of Risk Factors Affecting the Injury Risks in Vehicle-To-Pedestrian Crashes
Zhang, Guanjun; Cao, Libo; Hu, Jingwen; Yang, King H.
2008-01-01
The head, torso, and lower extremity are the most commonly injured body regions during vehicle-to-pedestrian crashes. A total of 312 cases were selected from the National Automotive Sampling System (NASS) Pedestrian Crash Data Study (PCDS) database to investigate factors affecting the likelihood of sustaining MAIS 3+, AIS 3+ head, AIS 3+ torso, and AIS 2+ lower extremity injuries during vehicle-to-pedestrian frontal crashes. The inclusion criteria were pedestrians: (a) aged 14 years or older, (b) with a height of 1.5 m and taller, and (c) who were injured in an upright standing position via vehicle frontal collision. The injury odds ratios (ORs) calculated from logistic regression analyses were used to evaluate the association between selected injury predictors and the odds of sustaining pedestrian head, torso, and lower extremity injuries. These predictors included a crash factor (impact speed), pedestrian factors (age, gender, height, and weight), and vehicle factors (front bumper central height, front bumper lead, ground to front/top transition point height (FTTPH), and rear hood opening distance (RHOD)). Results showed that impact speed was a statistically significant predictor for head, torso, and lower extremity injury odds, as expected. Comparison of people 65 years of age and older to young adults aged 14 to 64 showed that age was also a significant predictor for torso (p<0.001, OR=23.8) and lower extremity (p=0.020, OR=2.44) injury odds, but not for head injuries (p=0.661). Vehicles with higher FTTPH and more vertical frontal structures were aggressive to pedestrians, especially regarding injuries to the torso. A very short RHOD would be more likely to lead the pedestrian to impact the windshield and windshield frame, thus increasing the head injury risk. PMID:19026237
Liu, Xuejun; Yang, Jikuang
2003-12-01
To investigate the effects of vehicle impact velocity and front-end structure on the dynamic responses of child pedestrians, an extensive parametric study was carried out using two child mathematical models at 6 and 15 years old. The effect of the vehicle impact velocity was studied at 30, 40, and 50 km/h in terms of the head linear velocity, impact angle, and head angular velocity as well as various injury parameters concerning the head, chest, pelvis, and lower extremities. The variation of vehicle front-end shape was determined according to the shape corridors of modern vehicles, while the stiffness characteristics of the bumper, hood edge, and hood were varied within stiffness corridors obtained from dynamic component tests. The simulation results show that the vehicle impact speed is of great importance on the kinematics and resulting injury severity of child pedestrians. A significant reduction in all injury parameters can be achieved as the vehicle impact speed decreases to 30 km/h. The head and lower extremities of children are at higher injury risks than other body regions. Older children are exposed to higher injury risks to the head and lower leg, whereas younger ones sustain more severe impact loads to the pelvis and upper leg. The results from factorial analysis indicate that the hood-edge height has a significant effect on the kinematics and head impact responses of children. A higher hood edge could reduce the severity of head impact for younger children, but aggravate the risks of head injury for older ones. A significant interaction exists between the bumper height and the hood-edge height on the head impact responses of younger child. Nevertheless, improving the energy absorption performance of the hood seems effective for mitigating the severity of head injuries for children.
NASA Astrophysics Data System (ADS)
Jolly, William H.
1992-05-01
Relationships defining the ballistic limit of Space Station Freedom's (SSF) dual wall protection systems have been determined. These functions were regressed from empirical data found in Marshall Space Flight Center's (MSFC) Hypervelocity Impact Testing Summary (HITS) for the velocity range between three and seven kilometers per second. A stepwise linear least squares regression was used to determine the coefficients of several expressions that define a ballistic limit surface. Using statistical significance indicators and graphical comparisons to other limit curves, a final set of expressions is recommended for potential use in Probability of No Critical Flaw (PNCF) calculations for Space Station. The three equations listed below represent the mean curves for normal, 45 degree, and 65 degree obliquity ballistic limits, respectively, for a dual wall protection system consisting of a thin 6061-T6 aluminum bumper spaced 4.0 inches from a .125 inches thick 2219-T87 rear wall with multiple layer thermal insulation installed between the two walls. Normal obliquity is d(sub c) = 1.0514 v(exp 0.2983 t(sub 1)(exp 0.5228). Forty-five degree obliquity is d(sub c) = 0.8591 v(exp 0.0428) t(sub 1)(exp 0.2063). Sixty-five degree obliquity is d(sub c) = 0.2824 v(exp 0.1986) t(sub 1)(exp -0.3874). Plots of these curves are provided. A sensitivity study on the effects of using these new equations in the probability of no critical flaw analysis indicated a negligible increase in the performance of the dual wall protection system for SSF over the current baseline. The magnitude of the increase was 0.17 percent over 25 years on the MB-7 configuration run with the Bumper II program code.
Making `Internal Thermal Energy' Visible
NASA Astrophysics Data System (ADS)
Zou, Xueli
2004-09-01
In a 1992 paper published in this journal, Uri Ganiel described a pair of model carts used to demonstrate elastic and inelastic collisions. The wooden carts had low-friction wheels and a steel-strip bumper on one end. On one of the carts, a number of brass washers were rigidly mounted in vertical stacks to a wooden framework. The other cart was similar except that the washers were tied to rubber bands that were stretched horizontally and diagonally across the framework. When the first cart was rolled into a wall it bounced off with only a small reduction in speed ("elastic" collision). The second cart, on the other hand, was found to come nearly to a complete stop upon colliding with the wall ("inelastic" collision). Following the instructions given in Ganiel's paper, I built a pair of carts and demonstrated them to introductory-level physics students at a large public university. It was interesting to find that many students were distracted by the different-looking structures of the two model carts.2 They thought the different distributions of washers between the carts resulted in the rubber-band cart bouncing back a significantly shorter distance than the rigid-rod one after they both collided with a wall at the same initial speed. Apparently, the students had difficulties in understanding the collisions and used surface features to reason about them. To avoid this superficial distraction and to help students visualize easily "where the kinetic energy goes in an inelastic collision," I modified the rigid-rod cart to have washers fixed on hollow aluminum rods mounted at four different levels horizontally and diagonally (see Fig. 1). The new pair of the model carts look very similar to each other: They have the same bumpers, same wheels, same distributions of washers, and same masses.
A canopy architectural model to study the competitive ability of chickpea with sowthistle.
Cici, S-Zahra-Hosseini; Adkins, Steve; Hanan, Jim
2008-06-01
Improving the competitive ability of crops is a sustainable method of weed management. This paper shows how a virtual plant model of competition between chickpea (Cicer arietinum) and sowthistle (Sonchus oleraceus) can be used as a framework for discovering and/or developing more competitive chickpea cultivars. The virtual plant models were developed using the L-systems formalism, parameterized according to measurements taken on plants at intervals during their development. A quasi-Monte Carlo light-environment model was used to model the effect of chickpea canopy on the development of sowthistle. The chickpea-light environment-sowthistle model (CLES model) captured the hypothesis that the architecture of chickpea plants modifies the light environment inside the canopy and determines sowthistle growth and development pattern. The resulting CLES model was parameterized for different chickpea cultivars (viz. 'Macarena', 'Bumper', 'Jimbour' and '99071-1001') to compare their competitive ability with sowthistle. To validate the CLES model, an experiment was conducted using the same four chickpea cultivars as different treatments with a sowthistle growing under their canopy. The growth of sowthistle, both in silico and in glasshouse experiments, was reduced most by '99071-1001', a cultivar with a short phyllochron. The second rank of competitive ability belonged to 'Macarena' and 'Bumper', while 'Jimbour' was the least competitive cultivar. The architecture of virtual chickpea plants modified the light inside the canopy, which influenced the growth and development of the sowthistle plants in response to different cultivars. This is the first time that a virtual plant model of a crop-weed interaction has been developed. This virtual plant model can serve as a platform for a broad range of applications in the study of chickpea-weed interactions and their environment.
Fractal Risk Assessment of ISS Propulsion Module in Meteoroid and Orbital Debris Environments
NASA Technical Reports Server (NTRS)
Mog, Robert A.
2001-01-01
A unique and innovative risk assessment of the International Space Station (ISS) Propulsion Module is conducted using fractal modeling of the Module's response to the meteoroid and orbital debris environments. Both the environment models and structural failure modes due to the resultant hypervelocity impact phenomenology, as well as Module geometry, are investigated for fractal applicability. The fractal risk assessment methodology could produce a greatly simplified alternative to current methodologies, such as BUMPER analyses, while maintaining or increasing the number of complex scenarios that can be assessed. As a minimum, this innovative fractal approach will provide an independent assessment of existing methodologies in a unique way.
2014-12-05
NASA's Orion spacecraft is on rubber bumpers in the flooded well deck of the USS Anchorage in the Pacific Ocean about 600 miles off the coast of San Diego, California. Orion splashed down after its first flight test in Earth orbit. NASA, the U.S. Navy and Lockheed Martin are coordinating efforts to recover Orion and secure the spacecraft in the well deck of the USS Anchorage. Orion completed a two-orbit, four-and-a-half hour mission, to test systems critical to crew safety, including the launch abort system, the heat shield and the parachute system. The Ground Systems Development and Operations Program is leading the recovery efforts.
Meteoroid Bumper Experiment on Explorer 46
1981-01-01
4 1 21-6-9, now known as Nitronic 40 : P..•gistered trademark of Armco Steel Corp. £ 4 t During launch, the panels were rolled up like window shades...41 74 058 05 23 58 25 .136 End --- 26 .137 End --- 27 .136 (*) (*) 28 .135 73 025 20 01 44 73 026 13 25 28 29 .134 73 317 02 40 50 73 318 12 57 26 30...h m s y d h m s 38 0.119 End --- 39 .118 End --- 40 .120 End -- 41 .123 73 288 19 42 42 73 289 11 21 38 42 .128 End --- 43 .131 End 44 .133 End -- 45
McDonnell, Terence E
2010-05-01
AIDS media lead unexpected lives once distributed through urban space: billboards fade, posters go missing, bumper stickers travel to other cities. The materiality of AIDS campaign objects and of the urban settings in which they are displayed structures how the public interprets their messages. Ethnographic observation of AIDS media in situ and interview data reveal how the materiality of objects and places shapes the availability of AIDS knowledge in Accra, Ghana. Significantly for AIDS organizations, these material conditions often systematically obstruct access to AIDS knowledge for particular groups. Attending to materiality rethinks how scholars assess the cultural power of media.
Diseases of American lobsters (Homarus americanus): a review.
Cawthorn, Richard J
2011-01-01
The American lobster fishery is a significant economic driver in coastal communities of North America. Increasingly, the impacts of infectious disease are recognized as important components and factors in the population ecology and subsequent management of the lobster fishery. Both environmental and anthropogenic factors impact marine diseases. The review herein highlights aspects of several important bacterial, fungal and protistan diseases, including gaffkemia, shell disease, vibriosis, disease caused by species of Lagenidium, Haliphthoros and Fusarium, paramoebiasis and Bumper Car disease. As the global environment continues to change, these diseases could more severely affect both wild caught and impounded lobsters. Copyright © 2010 Elsevier Inc. All rights reserved.
Electron beam surface modifications in reinforcing and recycling of polymers
NASA Astrophysics Data System (ADS)
Czvikovszky, T.; Hargitai, H.
1997-08-01
Thermoplastic polymers can be fiber-reinforced in the recycling step through a reactive modification of the interface between the polymer matrix and fiber. Recollected automobile bumpers made of polypropylene copolymers have been reinforced during the reprocessing with eight different types of high-strength fibers, with waste cord-yarns of the tire industry. A thin layer reactive interface of acrylic oligomers has been applied and activated through low energy (175 keV) electron beam (EB). The upcycling (upgrading recycling) resulted in a series of extrudable and injection-mouldable, fiber-reinforced thermoplastic of enhanced bending strength, increased modulus of elasticity and acceptable impact strength. EB treatment has been compared with conventional methods.
NASA Astrophysics Data System (ADS)
Damberg, W.; Floegel, K.; Sahm, A.
1983-02-01
A noise reduction device for pneumatic nailers was developed. Conditions of use, range of products available, market regulations and measuring methods were studied. Ease of operation, service life, functional reliability and maintenance capacity were studied. Results show that the essential noise sources of the device are the compressed air blasts of the working and relation phases and the impact of the piston on the bumper. Packages of measures implemented on a laboratory scale indicate noise reduction possibilities for nailers in the short, medium and long term. The sound level of a single shot can be reduced from 110 dB to 93 dB.
NASA Technical Reports Server (NTRS)
Robinson, Ross B.; Morris, Odell A.
1960-01-01
An investigation has been conducted in the Langley 4- by 4-foot supersonic pressure tunnel to determine the aerodynamic characteristics in pitch of a two-stage-rocket model configuration which simulated the last two stages of the launching vehicle for an inflatable sphere. Tests were made through an angle-of-attack range from -6 deg to 18 deg at dynamic pressures of 102 and 255 pounds per square foot with corresponding Mach numbers of 1.89 and 1.98 for the model both with and without a bumper arrangement designed to protect the rocket casing from the outer shell of the vehicle.
Impact verification of space suit design for space station
NASA Technical Reports Server (NTRS)
Fish, Richard H.
1987-01-01
The ballistic limits of single sheet and double sheet structures made of 6061 T6 Aluminum of 1.8 mm and larger nominal thickness were investigated for projectiles of 1.5 mm diameter fired in the Vertical Gun Range Test Facility and NASA Ames Research Center. The hole diameters and sheet deformation behavior were studied for various ratios of sheet spacing to projectile diameter. The results indicate that for projectiles of less than 1.5 mm diameter the ballistic limit exceeds the nominal 10 km/sec orbital debris encounter velocity, if a single-sheet suit of 1.8 mm thickness is behind a single bumper sheet of 1 mm thickness spaced 12.5 mm apart.
NASA Astrophysics Data System (ADS)
Kim, Andrew C.
This research is motivated by recent activity to improve automotive safety, especially for pedestrians. In many parts of the world today, injuries and fatalities from road accidents are a significant problem. Safety features such as seat restraints and air bags provide considerable levels of protection for car occupants; however, no such protective measures currently exist for pedestrians. Drawing upon the success and effectiveness of occupant air bag systems, current research aims to develop similar devices for pedestrians. These active pedestrian protection systems deploy a safety feature such as an external air bag when a pedestrian is hit by a vehicle. Contact with the front bumper induces a body rotation that may result in a violent head collision. The deployable safety device provides a cushioning surface for the vulnerable pedestrian during impact. The challenge of such a system is an effective sensory unit that can rapidly and correctly discriminate pedestrian impacts from non-pedestrian ones. The fast kinematics of the automobile-pedestrian impact leaves a minimal amount of time for signal processing and computation. This research study focuses on a discrimination scheme that satisfies both the time and accuracy requirements for a proposed sensory system for pedestrian protection. A unique methodology was developed to identify structural impacts using dominant frequency features extracted from sensory data. Contact sensors mounted on the front bumper of an automobile measure the strain response from an impact event. The dominant frequencies obtained from these sensor signals are greatly influenced by the impact object's properties and can be used to discriminate between different objects. Extensive tests were conducted to gather sensor data and validate the proposed methodology and impact discrimination algorithm. Results of the impact tests indicate that the approach is sound, and the sensory system effectively identifies "pedestrian" impacts within a short period of time.
Points of view: where do we look when we watch TV?
Brasel, S Adam; Gips, James
2008-01-01
How is our gaze dispersed across the screen when watching television? An exploratory eyetracker study with a custom-designed show indicated a very strong center-of-screen bias with gaze points following a roughly normal distribution peaked near screen center. Examining the show across time revealed that people were rarely all looking at the same location, and the amount of gaze dispersion within frames was highly variable. Different forms of programming yielded different levels of dispersion: static network 'bumpers' created the tightest visual groupings, and gaze dispersion for frames with show content was less than the dispersion for commercials. Advertising frames with brand logos generated higher dispersion than the non-branded advertisement portions, and repeated advertisements generated higher dispersion than their first-run counterparts.
2014-12-05
SAN DIEGO, Calif. -- NASA's Orion spacecraft is on rubber bumpers in the flooded well deck of the USS Anchorage in the Pacific Ocean about 600 miles off the coast of San Diego, California. Orion splashed down after its first flight test in Earth orbit. NASA, the U.S. Navy and Lockheed Martin are coordinating efforts to recover Orion and secure the spacecraft in the well deck of the USS Anchorage. Orion completed a two-orbit, four-and-a-half hour mission, to test systems critical to crew safety, including the launch abort system, the heat shield and the parachute system. The Ground Systems Development and Operations Program is leading the recovery efforts. For more information, visit www.nasa.gov/orion Photo credit: NASA/Kenny Allen
Phenomena after meteoroid penetration of a bumper plate
NASA Technical Reports Server (NTRS)
Todd, F. C.
1972-01-01
The results are presented of a study to obtain a computer program for the penetration of a thin plate of aluminum by a sphere of rock. The study was divided into two projects. One project covers the initial impact, the crushing of the sphere of rock, the break up of the aluminum sheet, and the conversion of the sufficiently shock-compressed regions of rock and aluminum into a plasma. The other project considers the ejection of a cone of plasma with entrained particles from the impact zone, its expansion as it traverses a region of free space, and its impact on a stack of paper sheets. The ablation of fragments in penetrating the stack of paper sheets is also considered.
2011-02-24
CAPE CANAVERAL, Fla. -- Rubber bumpers are stowed on the deck of Freedom Star, one of NASA's solid rocket booster retrieval ships. The ship has set sail to be in position in the Atlantic Ocean to recover the spent boosters after space shuttle Discovery's STS-133 launch. The shuttle’s two solid rocket booster casings and associated flight hardware are recovered in the Atlantic Ocean after every launch by Liberty Star and Freedom Star. The boosters impact the Atlantic about seven minutes after liftoff and the retrieval ships are stationed about 10 miles from the impact area at the time of splashdown. After the spent segments are processed, they will be transported to Utah, where they will be refurbished and stored, if needed. Photo credit: NASA/Ben Smegelsky
Interpolation/extrapolation technique with application to hypervelocity impact of space debris
NASA Technical Reports Server (NTRS)
Rule, William K.
1992-01-01
A new technique for the interpolation/extrapolation of engineering data is described. The technique easily allows for the incorporation of additional independent variables, and the most suitable data in the data base is automatically used for each prediction. The technique provides diagnostics for assessing the reliability of the prediction. Two sets of predictions made for known 5-degree-of-freedom, 15-parameter functions using the new technique produced an average coefficient of determination of 0.949. Here, the technique is applied to the prediction of damage to the Space Station from hypervelocity impact of space debris. A new set of impact data is presented for this purpose. Reasonable predictions for bumper damage were obtained, but predictions of pressure wall and multilayer insulation damage were poor.
Long stroke jar bumper sub with safety sleeve
DOE Office of Scientific and Technical Information (OSTI.GOV)
Downen, J.L.; Sutliff, W.N.
1981-04-14
A hydraulic jar apparatus to be disposed in a drilling string embodying inner and outer telescopically arranged elements. Overlapping portions of the elements provide an annual chamber confining an operating liquid by an annular seal fixed to the outer element at the lower end of the chamber and an annular polly pack seal fixed to the outer element at the upper end of the chamber. A piston is extended radially from the inner element into the chamber and the chamber is divided by a cylinder on the outer element into low and high pressure sections. Impact shoulders are provided onmore » the elements in axially opposed relation to produce a jarring blow and the elements are telescopically coupled by a hexagonal spline sub assembly.« less
Have pedestrian subsystem tests improved passenger car front shape?
Li, Guibing; Wang, Fang; Otte, Dietmar; Cai, Zhihua; Simms, Ciaran
2018-06-01
Subsystem impactor tests are the main approaches for evaluation of safety performance of vehicle front design for pedestrian protection in legislative regulations. However, the main aspects of vehicle safety for pedestrians are shape and stiffness, and though it is clear that subsystem impact tests encourage lower vehicle front stiffness, it is unclear whether they promote improved vehicle front shapes for pedestrian protection. The purpose of this paper is therefore to investigate the effects of European pedestrian safety regulations on passenger car front shape and pedestrian injury risk using recent German In-Depth Accident Study (GIDAS) pedestrian collision data and numerical simulations. Firstly, a sample of 579 pedestrian collision cases involving 190 different car models between 2000-2015 extracted from the GIDAS was used to compare front-end shapes of passenger cars manufactured before and after the legislative pedestrian safety regulations were introduced in Europe. The focus was on changes in passenger car front shape and differences in pedestrian AIS2+ (Abbreviated Injury Scale at least level 2) leg, pelvis/femur and head injury risk observed in collisions. Multi-body simulations were also used to assess changes in vehicle aggressivity due to the observed changes in vehicle shape. The results show that newer passenger cars tend to have a flatter and wider bumper, higher bonnet leading edge, shorter and steeper bonnet and a shallower windscreen. Both the collision data and the numerical simulations indicate that newer passenger car front bumper designs are significantly safer for pedestrians' legs. However, the results also show that the higher bonnet leading edge in newer passenger cars is poor for pedestrian pelvis/femur protection, even though newer cars show an obviously lower AIS2+ injury risk to younger pedestrians in collisions. Newer cars have a lower AIS2+ head injury risk for pedestrians in collisions, but the numerical analysis indicate that this is not likely due to shape changes in passenger car fronts. Overall, the introduction of pedestrian safety regulations has resulted in reductions in pedestrian injury risk, but further benefits would accrue from tests which promote a lower bonnet leading edge. The influence of vehicle shape on pedestrian head injury risk remains unclear. Copyright © 2018 Elsevier Ltd. All rights reserved.
Carbon monoxide exposure from aircraft fueling vehicles.
McCammon, C S; Halperin, W F; Lemen, R A
1981-01-01
Investigators from the National Institute for Occupational Safety and Health observed deficiencies in maintenance of fueling trucks at an international airport. The exhaust system is vented under the front bumper, a standard design on fueling trucks which is intended to minimize the proximity of the exhaust system to the jet fuel in the vehicles. Carbon monoxide levels were measured in the cabs of 17 fueling trucks with windows closed, heaters on, and in different positions relative to the wind. One truck had an average CO level of 300 ppm, two exceeded 100 ppm, five others exceeded 50 ppm, while levels in the other nine averaged less than or equal to 500 ppm. Levels of CO depended on the mechanical condition of the vehicle and the vehicle's orientation to the wind. Stringent maintenance is required as the exhaust design is not fail-safe.
Effectiveness of metal matrix and ceramic matrix composites as orbital debris shield materials
NASA Technical Reports Server (NTRS)
Mcgill, Preston B.; Mount, Angela R.
1992-01-01
The effectiveness of two metal matrix composites and one ceramic matrix material in defeating hypervelocity impacts at about 3.8 km/s are evaluated to determine the potential of these composites as spacecraft shield materials. The metal matrix composites investigated consist of SiC particles (70 percent by volume) in an aluminum matrix and Al2O3 particles (50 percent by volume) in an Al matrix. The ceramic composite consists of ZrB2 platelets in a ZrC matrix. Both the metal matrix and ceramic matrix composites are found to perform as well or better than 6061-T6 aluminum, which is presently used in the Whipple type bumper shield of Space Station Freedom. Test results indicate that the composites tested may have applications as micrometeoroid/orbital debris shield materials.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
A hearing on the management of the Department of Interior's (DOI) Onshore Oil and Gas Leasing Program examined the question of geology versus market forces in determining lease boundaries and lease offerings. At issue was the question of possible fraud and the loss of revenue to states when leases are sold over the counter or by lottery, as described by Senator Dale Bumpers of Arkansas and the Governor of Wyoming, and the potential environmental damage that could result from an accelerated federal leasing program. Representatives of DOI described leasing procedures and efforts to balance the need for orderly exploration whilemore » also meeting economic and environmental goals. The witnesses also included representatives of environmental groups, geologists, and the oil and gas industry. An appendix with additional correspondence, statements, and other material submitted for the record follows the testimony of the 13 witnesses.« less
Experiments on a non-smoothly-forced oscillator
NASA Astrophysics Data System (ADS)
Virgin, Lawrence N.; George, Christopher; Kini, Ashwath
2015-12-01
This paper describes some typical behavior encountered in the response of a harmonically-excited mechanical system in which a severe nonlinearity occurs due to an impact. Although such systems have received considerable recent attention (most of it from a theoretical viewpoint), the system scrutinized in this paper also involves a discrete input of energy at the impact condition. That is, it is kicked when contact is made. One of the motivations for this work is related to a classic pinball machine in which a ball striking a bumper experiences a sudden impulse, introducing additional unpredictability to the motion of the ball. A one-dimensional analog of a pinball machine was the subject of a detailed mathematical study in Pring and Budd (2011), and the current paper details behavior obtained from a mechanical experiment and describes dynamics not observed in a conventional (passive) impact oscillator.
Shields for Enhanced Protection Against High-Speed Debris
NASA Technical Reports Server (NTRS)
Christiansen, Eric L.; Kerr, Justin H.
2003-01-01
A report describes improvements over the conventional Whipple shield (two thin, spaced aluminum walls) for protecting spacecraft against high-speed impacts of orbiting debris. The debris in question arise mainly from breakup of older spacecraft. The improved shields include exterior bumper layers composed of hybrid fabrics woven from combinations of ceramic fibers and high-density metallic wires or, alternatively, completely metallic outer layers composed of high-strength steel or copper wires. These shields are designed to be light in weight, yet capable of protecting against orbital debris with mass densities up to about 9 g/cm3, without generating damaging secondary debris particles. As yet another design option, improved shields can include sparsely distributed wires made of shape-memory metals that can be thermally activated from compact storage containers to form shields of predetermined shape upon arrival in orbit. The improved shields could also be used to augment shields installed previously.
Shields for Enhanced Protection Against High-Speed Debris
NASA Technical Reports Server (NTRS)
Christiansen, Eric L.; Kerr, Justin H.
2003-01-01
A report describes improvements over the conventional Whipple shield (two thin, spaced aluminum walls) for protecting spacecraft against high-speed impacts of orbiting debris. The debris in question arises mainly from breakup of older spacecraft. The improved shields include exterior "bumper" layers composed of hybrid fabrics woven from combinations of ceramic fibers and high-density metallic wires or, alternatively, completely metallic outer layers composed of high-strength steel or copper wires. These shields are designed to be light in weight, yet capable of protecting against orbital debris with mass densities up to about 9 g/cubic cm, without generating damaging secondary debris particles. As yet another design option, improved shields can include sparsely distributed wires made of shape memory metals that can be thermally activated from compact storage containers to form shields of predetermined shape upon arrival in orbit. The improved shields could also be used to augment shields installed previously.
Meteoroid/orbital debris impact damage predictions for the Russian space station MIR
NASA Technical Reports Server (NTRS)
Christiansen, E. L.; Hyde, J. L.; Lear, D.
1997-01-01
Components of the Mir space station have been exposed to the meteoroid/orbital debris (M/OD) environment for up to 11 years. During this period, no M/OD impact perforation of the pressure shell of the manned modules were reported. The NASA standard M/OD analysis code BUMPER was used to predict the probability of M/OD impact damage to various components of Mir. The analysis indicates a 1 in 2.2 chance that a M/OD impact would have caused a penetration resulting in a pressure leak of the Mir modules since its launch up to the February 1997. For the next five years, the estimated odds become 1 in 3. On an annual basis, penetration risks are 60 percent higher, on the average, in the next five years due to the larger size of Mir and the growth in the orbital debris population.
Validation of Organics for Advanced Stirling Convertor (ASC)
NASA Astrophysics Data System (ADS)
Shin, E. Eugene; Scheiman, Dan; Cybulski, Michelle; Quade, Derek; Inghram, Linda; Burke, Chris
2008-01-01
Organic materials are an essential part of the Advanced Stirling Convertor (ASC) construction as adhesives, potting, wire insulation, lubrication coatings, bobbins, bumpers, insulators, thread lockers. Since a long lifetime of such convertors to be used in the Advanced Stirling Radioisotope Generator (ASRG), sometimes up to 17 years, is required in various space applications such as Mars rovers, deep space missions, and lunar surface power, performance, durability and reliability of those organics should be critically evaluated in every possible material-process-fabrication-service environment relations. The objective of this study was to evaluate, validate, and recommend organics for use in ASCs. Systematic and extensive evaluation methodologies were developed and conducted for various organic materials. The overall efforts dealing with organics materials for the last several years are summarized in the key areas, e.g., process-fabrication optimization, adhesive bonding integrity, outgassing, thermal stability, and durability
Protein Crystal Growth Apparatus for Microgravity
NASA Technical Reports Server (NTRS)
Carter, Daniel C. (Inventor); Dowling, Timothy E. (Inventor)
1997-01-01
Apparatus for growing protein crystals under microgravity environment includes a plurality of protein growth assemblies stacked one above the other within a canister. Each of the protein growth assemblies includes a tray having a number of spaced apart growth chambers recessed below an upper surface. the growth chambers each having an upstanding pedestal and an annular reservoir about the pedestal for receiving a wick and precipitating agents. A well is recessed below the top of each pedestal to define a protein crystal growth receptacle. A flexible membrane is positioned on the upper surface of each tray and a sealing plate is positioned above each membrane, each sealing plate having a number of bumpers corresponding in number and alignment to the pedestals for forcing the membrane selectively against the upper end of the respective pedestal to seal the reservoir and the receptacle when the sealing plate is forced down.
NASA Technical Reports Server (NTRS)
Borroni-Bird, Christopher E. (Inventor); Lapp, Anthony Joseph (Inventor); Vitale, Robert L. (Inventor); Lee, Chunhao J. (Inventor); Bluethmann, William J. (Inventor); Ridley, Justin S. (Inventor); Junkin, Lucien Q. (Inventor); Ambrose, Robert O. (Inventor); Lutz, Jonathan J. (Inventor); Guo, Raymond (Inventor)
2015-01-01
A modular robotic vehicle includes a chassis, driver input devices, an energy storage system (ESS), a power electronics module (PEM), modular electronic assemblies (eModules) connected to the ESS via the PEM, one or more master controllers, and various embedded controllers. Each eModule includes a drive wheel containing a propulsion-braking module, and a housing containing propulsion and braking control assemblies with respective embedded propulsion and brake controllers, and a mounting bracket covering a steering control assembly with embedded steering controllers. The master controller, which is in communication with each eModule and with the driver input devices, communicates with and independently controls each eModule, by-wire, via the embedded controllers to establish a desired operating mode. Modes may include a two-wheel, four-wheel, diamond, and omni-directional steering modes as well as a park mode. A bumper may enable docking with another vehicle, with shared control over the eModules of the vehicles.
Influences of Vehicle Size and Mass and Selected Driver Factors on Odds of Driver Fatality
Padmanaban, Jeya
2003-01-01
Research was undertaken to determine vehicle size parameters influencing driver fatality odds, independent of mass, in two-vehicle collisions. Forty vehicle parameters were evaluated for 1,500 vehicle groupings. Logistic regression analyses show driver factors (belt use, age, drinking) collectively contribute more to fatality odds than vehicle factors, and that mass is the most important vehicular parameter influencing fatality odds for all crash configurations. In car crashes, other vehicle parameters with statistical significance had a second order effect compared to mass. In light truck-to-car crashes, “vehicle type-striking vehicle is light truck” was the most important parameter after mass, followed by vehicle height and bumper height, with second order effect. To understand the importance of “vehicle type” variable, further investigation of vehicle “stiffness” and other passenger car/light truck differentiating parameters is warranted. PMID:12941244
Research on Impact Stress and Fatigue Simulation of a New Down-to-the-Hole Impactor Based on ANSYS
NASA Astrophysics Data System (ADS)
Wu, Tao; Wang, Wei; Yao, Aiguo; Li, Yongbo; He, Wangyong; Fei, Dongdong
2018-06-01
In the present work, a down-to-the-hole electric hammer driven by linear motor is reported for drilling engineering. It differs from the common hydraulic or pneumatic hammers in that it can be applied to some special occasions without circulating medium due to its independence of the drilling fluid. The impact stress caused by the reciprocating motion between stator and rotor and the fatigue damage in key components of linear motor are analyzed by the ANSYS Workbench software and 3D model. Based on simulation results, the hammer's structure is optimized by using special sliding bearing, increasing the wall thickness of key and multilayer buffer gasket. Fatigue life and coefficient issues of the new structure are dramatically improved. However buffer gasket reduces the impactor's energy, different bumper structure effect on life improving and energy loss have also been elaborated.
NASA Technical Reports Server (NTRS)
Cody, Dennis J.; Concepcion, Allan G.; Watras, Edward C., III
1995-01-01
This project, conducted in cooperation with the NASA Advanced Space Design Program, is part of an ongoing effort to place an experiment package into space. The goal of this project is to build and test flight-ready hardware that can be launched from the Space Shuttle. Get Away Special Canister 2 (GASCan 2) consists of three separate experiments. The Ionospheric Properties and Propagation Experiment (IPPE) determines effects of the ionosphere on radio wave propagation. The Microgravity Ignition experiment (MGI) tests the effects of combustion in a microgravity environment. The Rotational Fluid Flow experiment (RFF) examines fluid behavior under varying levels of gravity. This year the following tasks were completed: design of the IPPE antenna, X- and J-cell battery boxes, J-cell battery box enclosure, and structural bumpers; construction of the MGI canisters, MGI mounting brackets, IPPE antenna, and battery boxes; and the selection of the RFF's operating fluid and the analysis of the fluid behavior under microgravity test conditions.
Optimization techniques applied to passive measures for in-orbit spacecraft survivability
NASA Technical Reports Server (NTRS)
Mog, Robert A.; Price, D. Marvin
1991-01-01
Spacecraft designers have always been concerned about the effects of meteoroid impacts on mission safety. The engineering solution to this problem has generally been to erect a bumper or shield placed outboard from the spacecraft wall to disrupt/deflect the incoming projectiles. Spacecraft designers have a number of tools at their disposal to aid in the design process. These include hypervelocity impact testing, analytic impact predictors, and hydrodynamic codes. Analytic impact predictors generally provide the best quick-look estimate of design tradeoffs. The most complete way to determine the characteristics of an analytic impact predictor is through optimization of the protective structures design problem formulated with the predictor of interest. Space Station Freedom protective structures design insight is provided through the coupling of design/material requirements, hypervelocity impact phenomenology, meteoroid and space debris environment sensitivities, optimization techniques and operations research strategies, and mission scenarios. Major results are presented.
Three Point Bending of Top-Hat Stiffened Chopped Short Fibre Ramie/HDPE Thermoplastic Composite Beam
NASA Astrophysics Data System (ADS)
Hadi, Bambang K.; Nuril, Yogie S.
2018-04-01
The use of natural fibre and thermoplastic matrices in composite materials increased significantly during the last decade especially in the automotive industries. Ramie is one of these potential natural fibres. In this paper, a three point bending of top-hat beam made of ramie/HDPE (High-Density-Polyethylene) composites was performed. Top-hat stiffened structures were common structures found in the aerospace industries. Nevertheless, these structures are beginning to be applied in automotive structures in the forms of chassis and bumpers. The ramie/HDPE composite was manufactured using hot-press technique. The temperature was set to be 135°C and the pressure was 6 bars. Chopped short ramie fibre was used, due to good drape ability characteristics. The experiments showed that the beams produced a large non-linearity. Linear Finite Element Analysis was carried out to be compared with the experimental data. The differences are reasonable.
Li, Guibing; Yang, Jikuang; Simms, Ciaran
2017-03-01
Vehicle front shape has a significant influence on pedestrian injuries and the optimal design for overall pedestrian protection remains an elusive goal, especially considering the variability of vehicle-to-pedestrian accident scenarios. Therefore this study aims to develop and evaluate an efficient framework for vehicle front shape optimization for pedestrian protection accounting for the broad range of real world impact scenarios and their distributions in recent accident data. Firstly, a framework for vehicle front shape optimization for pedestrian protection was developed based on coupling of multi-body simulations and a genetic algorithm. This framework was then applied for optimizing passenger car front shape for pedestrian protection, and its predictions were evaluated using accident data and kinematic analyses. The results indicate that the optimization shows a good convergence and predictions of the optimization framework are corroborated when compared to the available accident data, and the optimization framework can distinguish 'good' and 'poor' vehicle front shapes for pedestrian safety. Thus, it is feasible and reliable to use the optimization framework for vehicle front shape optimization for reducing overall pedestrian injury risk. The results also show the importance of considering the broad range of impact scenarios in vehicle front shape optimization. A safe passenger car for overall pedestrian protection should have a wide and flat bumper (covering pedestrians' legs from the lower leg up to the shaft of the upper leg with generally even contacts), a bonnet leading edge height around 750mm, a short bonnet (<800mm) with a shallow or steep angle (either >17° or <12°) and a shallow windscreen (≤30°). Sensitivity studies based on simulations at the population level indicate that the demands for a safe passenger car front shape for head and leg protection are generally consistent, but partially conflict with pelvis protection. In particular, both head and leg injury risk increase with increasing bumper lower height and depth, and decrease with increasing bonnet leading edge height, while pelvis injury risk increases with increasing bonnet leading edge height. However, the effects of bonnet leading edge height and windscreen design on head injury risk are complex and require further analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.
Smirenin, S A; Fetisov, V A; Grigoryan, V G; Gusarov, A A; Kucheryavets, Yu O
The disabling injuries inflicted during road traffic accidents (RTA) create a serious challenge for the public health services and are at the same time a major socio-economic problem in the majority of the countries throughout the world. The injuries to the lower extremities of the pedestrians make up the largest fraction of the total number of the non-lethal RTA injuries. Most of them are responsible for the considerable deterioration of the quality of life for the participants in the accidents during the subsequent period. The objective of the present study was to summarize the currently available results of experimental testing of the biomechanical models of the pedestrians' lower extremities in the framework of the program for the prevention of the road traffic accidents as proposed by the World Health Organization (WHO, 2004). The European Enhanced Safety Vehicle Committee (EEVC) has developed a series of crash-tests with the use of the models of the pedestrians' lower extremities simulating the vehicle bumper-pedestrian impact. The models are intended for the assessment of the risk of the tibia fractures and the injuries to the knee joint ligaments. The experts of EEVC proposed the biomechanical criteria for the acceleration of the knee and talocrural parts of the lower limbs as well as for the shear displacement of the knee and knee-bending angle. The engineering solution of this problem is based on numerous innovation proposals being implemented in the machine-building industry with the purpose of reducing the stiffness of structural elements of the bumper and other front components of a modern vehicle designed to protect the pedestrians from severe injuries that can be inflicted in the road traffic accidents. The activities of the public health authorities (in the first place, bureaus of forensic medical expertise and analogous facilities) have a direct bearing on the solution of the problem of control of road traffic injuries because they are possessed of comprehensive and reliable objective information about all forms of the damage to health associated with vehicle-pedestrian collisions and their victims' condition. It is concluded that making use of the experience and professional knowledge of forensic medical experts and automotive specialists could considerably contribute to the enhancement of safety of all the participants in the vehicular traffic.
Hypervelocity Impact Performance of Open Cell Foam Core Sandwich Panel Structures
NASA Technical Reports Server (NTRS)
Ryan, Shannon; Christiansen, Eric; Lear, Dana
2009-01-01
Metallic foams are a relatively new class of materials with low density and novel physical, mechanical, thermal, electrical and acoustic properties. Although incompletely characterized, they offer comparable mechanical performance to traditional spacecraft structural materials (i.e. honeycomb sandwich panels) without detrimental through-thickness channeling cells. There are two competing types of metallic foams: open cell and closed cell. Open cell foams are considered the more promising technology due to their lower weight and higher degree of homogeneity. Leading micrometeoroid and orbital debris shields (MMOD) incorporate thin plates separated by a void space (i.e. Whipple shield). Inclusion of intermediate fabric layers, or multiple bumper plates have led to significant performance enhancements, yet these shields require additional non-ballistic mass for installation (fasteners, supports, etc.) that can consume up to 35% of the total shield weight [1]. Structural panels, such as open cell foam core sandwich panels, that are also capable of providing sufficient MMOD protection, represent a significant potential for increased efficiency in hypervelocity impact shielding from a systems perspective through a reduction in required non-ballistic mass. In this paper, the results of an extensive impact test program on aluminum foam core sandwich panels are reported. The effect of pore density, and core thickness on shielding performance have been evaluated over impact velocities ranging from 2.2 - 9.3 km/s at various angles. A number of additional tests on alternate sandwich panel configurations of comparable-weight have also been performed, including aluminum honeycomb sandwich panels (see Figure 1), Nomex honeycomb core sandwich panels, and 3D aluminum honeycomb sandwich panels. A total of 70 hypervelocity impact tests are reported, from which an empirical ballistic limit equation (BLE) has been derived. The BLE is in the standard form suitable for implementation in risk analysis software, and includes the effect of panel thickness, core density, and facesheet material properties. A comparison between the shielding performance of foam core sandwich panel structures and common MMOD shielding configurations is made for both conservative (additional 35% non-ballistic mass) and optimistic (additional mass equal to 30% of bumper mass) considerations. Suggestions to improve the shielding performance of foam core sandwich panels are made, including the use of outer mesh layers, intermediate fabric/composite layers, and varying pore density.
Consideration of alternative designs for a Percutaneous Endoscopic Gastrostomy feeding tube
NASA Astrophysics Data System (ADS)
Yerrabolu, Santosh Rohit
The inability of some people to chew or swallow foods (but can digest foods) due to problems associated with various diseases and complications leads them to insufficient nutritional intake and loss of quality of life. These individuals are generally provided with nutritional support by means of injecting or infusing food directly into their stomachs or small intestines via feeding tubes. Gastrostomy feeding tubes (G-tubes) are used when such nutritional support is required for over 3-6 weeks. Percutaneous Endoscopic Gastrostomy (PEG) tubes are one of the most widely used G- Tubes and devices which are inserted via an incision through the abdominal wall either through a pull or push method. This investigation proposes conceptual alternative Percutaneous Endoscopy Gastrostomy (PEG) feeding tube designs with optimized materials selection to be used for their construction. The candidate materials were chosen from 18 commercial catheters, 2 reference grade polymers and a commercial polymer; using tissue-catheter-friction testing and surface chemistry characterization (Infrared spectroscopy and Critical Surface Tension approximation). The main objectives considered were to minimize slipping/dislodgement of gastrostomy tube/seal, to reduce peristomal leakage, and to attain size variability of PEG tubes while maintaining a low profile. Scanning Electron Microscope- Energy Dispersive X-ray Spectroscopy was employed to further determine the filler materials used in the samples. Nylon coated with fatty ester and filled with Barium sulphate was determined as the optimum material for the construction of the tube part of the feeding tubes to reduce slipping/dislodgment of gastrostomy tube/seal and to minimize peristomal leakage. Nylon coated with fatty ester and filled with Silica is the suggested as a candidate material for construction of the bumper/mushroom sections of the feeding tubes to avoid the Buried Bumper Syndrome. Fused Deposition Modeling, Selective Laser Sintering and/or 3-D printing are proposed for manufacturing of the product. Radio Frequency Glow Discharge Treatment is proposed as a sterilizing technique. Further investigations suggested are pilot Finite Element Analysis of the biomechanics involved and the subsequent validation and optimization of the conceptual designs apart from pursuing materials performance evaluation with stomach tissue-skin composites and long-term placement of tubes/ catheters at variable surface roughness profiles, filler materials, modulus of rigidities, tube-pull-through speeds and tissue stretch ratios.
Corrective Action Plan for Corrective Action Unit 563: Septic Systems, Nevada Test Site, Nevada
DOE Office of Scientific and Technical Information (OSTI.GOV)
NSTec Environmental Restoration
This Corrective Action Plan (CAP) has been prepared for Corrective Action Unit (CAU) 563, Septic Systems, in accordance with the Federal Facility Agreement and Consent Order. CAU 563 consists of four Corrective Action Sites (CASs) located in Areas 3 and 12 of the Nevada Test Site. CAU 563 consists of the following CASs: CAS 03-04-02, Area 3 Subdock Septic Tank CAS 03-59-05, Area 3 Subdock Cesspool CAS 12-59-01, Drilling/Welding Shop Septic Tanks CAS 12-60-01, Drilling/Welding Shop Outfalls Site characterization activities were performed in 2007, and the results are presented in Appendix A of the CAU 563 Corrective Action Decision Document.more » The scope of work required to implement the recommended closure alternatives is summarized below. CAS 03-04-02, Area 3 Subdock Septic Tank, contains no contaminants of concern (COCs) above action levels. No further action is required for this site; however, as a best management practice (BMP), all aboveground features (e.g., riser pipes and bumper posts) will be removed, the septic tank will be removed, and all open pipe ends will be sealed with grout. CAS 03-59-05, Area 3 Subdock Cesspool, contains no COCs above action levels. No further action is required for this site; however, as a BMP, all aboveground features (e.g., riser pipes and bumper posts) will be removed, the cesspool will be abandoned by filling it with sand or native soil, and all open pipe ends will be sealed with grout. CAS 12-59-01, Drilling/Welding Shop Septic Tanks, will be clean closed by excavating approximately 4 cubic yards (yd3) of arsenic- and chromium-impacted soil. In addition, as a BMP, the liquid in the South Tank will be removed, the North Tank will be removed or filled with grout and left in place, the South Tank will be filled with grout and left in place, all open pipe ends will be sealed with grout or similar material, approximately 10 yd3 of chlordane-impacted soil will be excavated, and debris within the CAS boundary will be removed. CAS 12-60-01, Drilling/Welding Shop Outfalls, contains no COCs above action levels. No further action is required for this site; however, as a BMP, three drain pipe openings will be sealed with grout.« less
Surveys of ISS Returned Hardware for MMOD Impacts
NASA Technical Reports Server (NTRS)
Hyde, James; Christiansen, E.; Lear, D.; Nagy, K.
2017-01-01
Since February 2001, the Hypervelocity Impact Technology (HVIT) group at the Johnson Space Center in Houston has performed 26 post-flight inspections on space exposed hardware that have been returned from the International Space Station. Data on 1,024 observations of MMOD damage have been collected from these inspections. Survey documentation typically includes impact feature location and size measurements as well as microscopic photography (25-200x). Sampling of impacts sites for projectile residue was performed for the largest features. Results of Scanning Electron Microscopy (SEM) analysis to discern impactor source is included in the database. This paper will summarize the post-flight MMOD inspections, and focus on two inspections in particular: (1) Pressurized Mating Adapter-2 (PMA-2) cover returned in 2015 after 1.6 years exposure with 26 observed damages, and (2) Airlock shield panels returned in 2010 after 8.7 years exposure with 58 MMOD damages. Feature sizes from the observed data are compared to predictions using the Bumper risk assessment code.
Surveys of Returned ISS Hardware for MMMOD Impacts
NASA Technical Reports Server (NTRS)
Hyde, J. L.; Christiansen, E. L.; Lear, D. M.; Nagy, K.; Berger, E. L.
2017-01-01
Since February 2001, the Hypervelocity Impact Technology (HVIT) group at the Johnson Space Center (JSC) in Houston has performed 35 post-flight inspections on space exposed hardware returned from the International Space Station (ISS). Data on 1,188 observations of micrometeoroid and orbital debris (MMOD) damage have been collected from these inspections. Survey documentation typically includes impact feature location and size measurements as well as microscopic photography (25-200x). Sampling of impacts sites for projectile residue was performed for the largest features. Results of energy dispersive X-ray spectroscopic analysis to discern impactor source are included in the database when available. This paper will focus on two inspections, the Pressurized Mating Adapter 2 (PMA-2) cover returned in 2015 after 1.6 years exposure with 26 observed impact features, and two Airlock shield panels returned in 2010 after 8.75 years exposure with 58 MMOD impacts. Feature sizes from the observed data are compared to predictions using the Bumper 3 risk assessment code.
High Energy Wide Area Blunt Impact on Composite Aircraft Structures
NASA Astrophysics Data System (ADS)
DeFrancisci, Gabriela K.
The largest source of damage to commercial aircraft is caused by accidental contact with ground service equipment (GSE). The cylindrical bumper typically found on GSE distributes the impact load over a large contact area, possibly spanning multiple internal structural elements (frame bays) of a stiffened-skin fuselage. This type of impact can lead to damage that is widespread and difficult to detect visually. To address this problem, monolithic composite panels of various size and complexity have been modeled and tested quasi-statically and dynamically. The experimental observations have established that detectability is dependent on the impact location and immediately-adjacent internal structure of the panel, as well as the impactor geometry and total deformation of the panel. A methodology to model and predict damage caused by wide area blunt impact events was established, which was then applied to more general cases that were not tested in order to better understand the nature of this type of impact event and how it relates to the final damage state and visual detectability.
NASA Technical Reports Server (NTRS)
Henderson, A. J., Jr.
1984-01-01
Tentatively scheduled to fly on STS-17 (41G), this get away special aims to demonstrate amateur radio transmissions to global ground stations in the English language. Experiments No. 1, 2, and 3 use the micro-gravity of space flight to study the solidification of lead-antimony and aluminum-copper alloys, the germination of radish seeds, and the growth of potassium-tetracyanoplatinate hydrate crystals in an aqueous solution. Flight results are to be compared with Earth-based data. Experiment No. 4 (the Marshall Amateur Radio Club Experiment - MARCE) features radio transmissions and also provides timing for the start of all other experiments. A microprocessor obtains real-time data from all experiments as well as temperature and pressure measurements within the GAS canister. These data are to be transmitted on previously announced amateur radio frequencies after they are converted into the English language by a digitalker for general reception. The support structure for the G #007 experiments consists of two primary plates and four bumper assemblies.
Time-dependent crashworthiness of polyurethane foam
NASA Astrophysics Data System (ADS)
Basit, Munshi Mahbubul; Cheon, Seong Sik
2018-05-01
Time-dependent stress-strain relationship as well as crashworthiness of polyurethane foam was investigated under constant impact energy with different velocities, considering inertia and strain-rate effects simultaneously during the impact testing. Even though the impact energies were same, the percentage in increase in densification strain due to higher impact velocities was found, which yielded the wider plateau region, i.e. growth in crashworthiness. This phenomenon is analyzed by the microstructure of polyurethane foam obtained from scanning electron microscopy. The equations, coupled with the Sherwood-Frost model and the impulse-momentum theory, were employed to build the constitutive equation of the polyurethane foam and calculate energy absorption capacity of the foam. The nominal stress-strain curves obtained from the constitutive equation were compared with results from impact tests and were found to be in good agreement. This study is dedicated to guiding designer use polyurethane foam in crashworthiness structures such as an automotive bumper system by providing crashworthiness data, determining the crush mode, and addressing a mathematical model of the crashworthiness.
NASA Technical Reports Server (NTRS)
Murray, K. A.
1988-01-01
A system of heat pipe radiators has been designed to provide waste heat rejection for an inertial fusion powered spacecraft capable of manned missions to other planets. The radiators are arrays of unfinned, arterial heat pipes operating at 1500 and 900 K. Liquid metal coolant carries up to 8000 MW of waste heat through feed pipes from on-board components (laser drivers and coil shield). The radiators do not rely on armor for protection from micrometeoroid penetration. An armored radiator design for this application with a 99 percent survivability would have a specific mass of 0.06 to 0.11 kg/kW at 1500 K. Instead, a segmentation of heat pipes is used, and bumpers are utilized to protect the feed pipes. This design reduces the specific mass to 0.015 to 0.04 kg/kW for the coil shield radiator (1500 K) and 0.06 to 0.12 kg/kW for the laser driver radiator (900 K).
Combined Aero and Underhood Thermal Analysis for Heavy Duty Trucks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vegendla, Prasad; Sofu, Tanju; Saha, Rohit
2017-01-31
Aerodynamic analysis of the medium-duty delivery truck was performed to achieve vehicle design optimization. Three dimensional CFD simulations were carried out for several improved designs, with a detailed external component analysis of wheel covers, side skirts, roof fairings, and rounded trailer corners. The overall averaged aerodynamics drag reduction through the design modifications were shown up to 22.3% through aerodynamic considerations alone, which is equivalent to 11.16% fuel savings. The main identified fuel efficiencies were based on second generation devices, including wheel covers, side skirts, roof fairings, and rounded trailer corners. The important findings of this work were; (i) the optimummore » curvature radius of the rounded trailer edges found to be 125 mm, with an arc length of 196.3 mm, (ii) aerodynamic drag reduction increases with dropping clearance of side skirts between wheels and ground, and (iii) aerodynamic drag reduction increases with an extension of front bumper towards the ground.« less
Study of Thermal Control Systems for orbiting power systems
NASA Technical Reports Server (NTRS)
Howell, H. R.
1981-01-01
Thermal control system designs were evaluated for the 25 kW power system. Factors considered include long operating life, high reliability, and meteoroid hazards to the space radiator. Based on a cost advantage, the bumpered pumped fluid radiator is recommended for the initial 25 kW power system and intermediate versions up to 50 kW. For advanced power systems with heat rejection rates above 50 kW the lower weight of the advanced heat pipe radiator offsets the higher cost and this design is recommended. The power system payloads heat rejection allocations studies show that a centralized heat rejection system is the most weight and cost effective approach. The thermal interface between the power system and the payloads was addressed and a concept for a contact heat exchanger that eliminates fluid transfer between the power system and the payloads was developed. Finally, a preliminary design of the thermal control system, with emphasis on the radiator and radiator deployment mechanism, is presented.
Child pedestrian anthropometry: evaluation of potential impact points during a crash.
Serre, Thierry; Lalys, Loïc; Bartoli, Christophe; Christia-Lotter, Amandine; Leonetti, Georges; Brunet, Christian
2010-11-01
This paper highlights the potential impact points of a child pedestrian during a crash with the front end of a vehicle. Child anthropometry was defined for ages between 3 and 15 years. It was based on the measurement of seven different segment body heights (knee, femur, pelvis, shoulder, neck, chin, vertex) performed on about 2,000 French children. For each dimension, the 5(th), 50(th) and 95(th) percentile values were reported, and the corresponding linear regression lines were given. Then these heights were confronted with three different vehicle shapes, corresponding to a passenger car, a sport utility vehicle and a light truck, to identify impact points. In particular, we show that the thigh is directly hit by the bumper for children above 12 years of age, whereas the head principally impacts the hood. The influence of child anthropometry on the pedestrian trajectory and the comparison with test procedures in regulation are discussed. 2010 Elsevier Ltd. All rights reserved.
Meteoroid-bumper interactions program
NASA Technical Reports Server (NTRS)
Gough, P. S.
1970-01-01
An investigation has been made of the interaction of meteoroids with shielded structures. The interaction has been simulated by the impact of Lexan cylinders onto lead shields in order to provide the vaporous debris believed to be created by meteoroid impact on a space vehicle. Shock compression data for Lexan was determined. This, in combination with the known shock compression data for the lead shield, has permitted the definition of the initial high pressure states in the impacted projectile and shield. The debris from such impact events has been permitted to interact with aluminum main walls. The walls were chosen to be sufficiently large to be effectively infinite in diameter compared to the loaded area. The thickness of the wall and the spacing from the shield were varied to determine the effect of these parameters. In addition, the effect of having a body of water behind the wall has been assessed. Measurements of the stagnation pressure in the debris cloud have been made and correlated with the response of the main wall.
NASA Astrophysics Data System (ADS)
Aseer, J. R.; Sankaranarayanasamy, K.
2017-12-01
Today, the utilization of biodegradable materials has been hogging much attention throughout the world. Due to the disposal issues of petroleum based products, there is a focus towards developing biocomposites with superior mechanical properties and degradation rate. In this research work, Hibiscus Sabdariffa (HS) fibers were used as the reinforcement for making biocomposites. The HS fibers were reinforced in the polyester resin by compression moulding method. Water absorption studies of the composite at room temperature are carried out as per ASTM D 570. Also, degradation behavior of HS/Polyester was done by soil burial method. The HS/polyester biocomposites containing 7.5 wt% of HS fiber has shown higher value of tensile strength. The tensile strength retention of the HS/Polyester composites are higher than the neat polyester composites. This value increases with increase of HS fiber loading in the composites. The results indicated that HS/polyester biocomposites can be used for making automobile components such as bumper guards etc.
JSC Director's Discretionary Fund 1992 Annual Report
NASA Technical Reports Server (NTRS)
Jenkins, Lyle (Compiler)
1993-01-01
Annual report of the Johnson Space Center Director's Discretionary Fund documenting effective use of resources. The $1,694,000 funding for FY92 was distributed among 27 projects. The projects are an overall aid to the NASA mission, as well as providing development opportunities for the science and engineering staff with eventual spinoff to commercial uses. Projects described include space-based medical research such as the use of stable isotopes of deuterium and oxygen to measure crew energy use and techniques for noninvasive motion sickness medication. Recycling essentials for space crew support is conducted in the Regenerative Life Support and the Hybrid Regenerative Water Recovery test beds. Two-phase fluid flow simulated under low-gravity conditions, hypervelocity particle impact on open mesh bumpers, and microcalorimetry to measure the long-term hydrazine/material compatibility were investigated. A patent application was made on a shape-memory-alloy release nut. Computer estimate of crew accommodations for advanced concepts was demonstrated. Training techniques were evaluated using multimedia and virtual environment. Upgrades of an electronic still camera provide high resolution images from orbit are presented.
Mechanical Properties and Microstructure of High-Strength Steel Controlled by Hot Stamping Process
NASA Astrophysics Data System (ADS)
Ou, Hang; Zhang, Xu; Xu, Junrui; Li, Guangyao; Cui, Junjia
2018-03-01
A novel design and manufacturing method, dubbed "precast," of the cooling system and tools for a hot forming process was proposed in this paper. The integrated structures of the punch and blank holder were determined by analyzing the bending and reverse-bending deformation of the forming parts. The desired crashworthiness performance of an automotive front bumper constructed with this process was obtained by a tailored phase transformation, which generated martensite-bainite in the middle and full martensite transformation in the corner areas. Varying cooling effects in the formed parts caused the highest temperature to be located in the bottom and the lowest on the end of the formed parts. Moreover, the microstructural distributions demonstrated that the bottom possessed a relatively lower content of martensite, while, conversely, the end possessed a higher content. This was precisely the most desired phase distributions for the hot formed parts. For the six-process cycle stamping, the temperatures reached a stable status after an initial rapid increase in the first three process cycles. The microstructural results verified the feasibility of the hot forming tools under multiprocess cycles.
Hypervelocity impact testing above 10 km/s of advanced orbital debris shields
NASA Astrophysics Data System (ADS)
Christiansen, Eric L.; Crews, Jeanne Lee; Kerr, Justin H.; Chhabildas, Lalit C.
1996-05-01
NASA has developed enhanced performance shields to improve the protection of spacecraft from orbital debris and meteoroid impacts. One of these enhanced shields includes a blanket of Nextel™ ceramic fabric and Kevlar™ high strength fabric that is positioned midway between an aluminum bumper and the spacecraft pressure wall. As part of the evaluation of this new shielding technology, impact data above 10 km/sec has been obtained by NASA Johnson Space Center (JSC) from the Sandia National Laboratories HVL ("hypervelocity launcher") and the Southwest Research Institute inhibited shaped charge launcher (ISCL). The HVL launches flyer-plates in the velocity range of 10 to 15 km/s while the ISCL launches hollow cylinders at ˜11.5 km/s. The >10 km/s experiments are complemented by hydrocode analysis and light-gas gun testing at the JSC Hypervelocity Impact Test Facility (HIT-F) to assess the effects of projectile shape on shield performance. Results from the testing and analysis indicate that the Nextel™/Kevlar™ shield provides superior protection performance compared to an all-aluminum shield alternative.
Osteological evidence of genetic divergence of lake trout (Salvelinus namaycush) in Lake Superior
Burnham-Curtis, Mary K.; Smith, Gerald R.
1994-01-01
Three phenotypes of Salvelinus namaycush in Lake Superior, the lean, siscowet, and bumper, are traditionally identified primarily by fat content and body shape. Their taxonomic status is in question because of intermediates as well as the possibility that the diagnostic characters are ecophenotypic. Two osteological characters, the dorsal opercular notch (first recorded by Agassiz in his description of the siscowet) and radii on the anterodorsal part of the supraethmoid, differ between most leans and siscowets. The notch in the opercle near its articulation with the hyomandibular bone is present in humpers, usually present in siscowets, and usually absent in leans. Radii on the anterodorsal surface of the supraethmoid bone usually are found in siscowets and humpers but usually are absent in leans. The correlations among these characters and other features of the phenotype indicate a significant level of differentiation between the three phenotypes. Available evidence suggests that the differentiation is genetic. The frequency of mixed phenotypes is evidence of limited gene flow among the phenotypes. The siscowet and humper phenotypes apparently originated in Lake Superior in postglacial time.
4th Day of Equipment Being Loaded for Recovery of Orion
2014-11-20
The Orion handling fixture, special bumpers and other ground support equipment are secured in the well deck of the USS Anchorage at Naval Base San Diego in California. The equipment will be used during recovery of the Orion crew module after its first flight test. Before launch of Orion on a Delta IV Heavy rocket from Cape Canaveral Air Force Station in Florida, NASA, Lockheed Martin and U.S. Navy personnel will head out to sea in the USS Anchorage and the USNS Salvor, a salvage ship, and wait for splashdown of the Orion crew module in the Pacific Ocean. The Ground Systems Development and Operations Program will lead the recovery efforts. Orion is the exploration spacecraft designed to carry astronauts to destinations not yet explored by humans, including an asteroid and Mars. It will have emergency abort capability, sustain the crew during space travel and provide safe re-entry from deep space return velocities. The first unpiloted flight test of Orion is scheduled to launch in December atop a United Launch Alliance Delta IV Heavy rocket and in 2018 on NASA’s Space Launch System rocket.
Ultra wideband ground penetrating radar imaging of heterogeneous solids
Warhus, J.P.; Mast, J.E.
1998-11-10
A non-invasive imaging system for analyzing engineered structures comprises pairs of ultra wideband radar transmitters and receivers in a linear array that are connected to a timing mechanism that allows a radar echo sample to be taken at a variety of delay times for each radar pulse transmission. The radar transmitters and receivers are coupled to a position determining system that provides the x,y position on a surface for each group of samples measured for a volume from the surface. The radar transmitter and receivers are moved about the surface, e.g., attached to the bumper of a truck, to collect such groups of measurements from a variety of x,y positions. Return signal amplitudes represent the relative reflectivity of objects within the volume and the delay in receiving each signal echo represents the depth at which the object lays in the volume and the propagation speeds of the intervening material layers. Successively deeper z-planes are backward propagated from one layer to the next with an adjustment for variations in the expected propagation velocities of the material layers that lie between adjacent z-planes. 11 figs.
Ultra wideband ground penetrating radar imaging of heterogeneous solids
Warhus, John P.; Mast, Jeffrey E.
1998-01-01
A non-invasive imaging system for analyzing engineered structures comprises pairs of ultra wideband radar transmitters and receivers in a linear array that are connected to a timing mechanism that allows a radar echo sample to be taken at a variety of delay times for each radar pulse transmission. The radar transmitters and receivers are coupled to a position determining system that provides the x,y position on a surface for each group of samples measured for a volume from the surface. The radar transmitter and receivers are moved about the surface, e.g., attached to the bumper of a truck, to collect such groups of measurements from a variety of x,y positions. Return signal amplitudes represent the relative reflectivity of objects within the volume and the delay in receiving each signal echo represents the depth at which the object lays in the volume and the propagation speeds of the intervening material layers. Successively deeper z-planes are backward propagated from one layer to the next with an adjustment for variations in the expected propagation velocities of the material layers that lie between adjacent z-planes.
Lightweight Radiator System for a Spacecraft
NASA Technical Reports Server (NTRS)
Copeland, Robert J.; Mason, Georgia; Weislogel, Mark M.
2005-01-01
Three documents describe various aspects of a proposed lightweight, deployable radiator system for dissipating excess heat from the life-support system of a habitable spacecraft. The first document focuses on a radiator tube that would include a thin metal liner surrounded and supported by a thicker carbon-fiber-reinforced composite tubular structure that, in turn, would be formed as part of a unitary composite radiator-fin structure consisting mostly of a sheet of reticulated vitreous carbon laminated between carbon-fiber-reinforced face sheets. The thermal and mechanical properties, including the anisotropies, of the component materials are taken into account in the design. The second document describes thermo-structural bumpers, in the form of exterior multiple-ply carbon-fiber sheets enclosing hollows on opposite sides of a radiator fin, which would protect the radiator tube against impinging micrometeors and orbital debris. The third document describes a radiator system that would include multiple panels containing the aforementioned components, among others. The system would also include mechanisms for deploying the panels from compact stowage. Deployment would not involve breaking and remaking of fluid connections to the radiator panels.
An approach to achieve progress in spacecraft shielding
NASA Astrophysics Data System (ADS)
Thoma, K.; Schäfer, F.; Hiermaier, S.; Schneider, E.
2004-01-01
Progress in shield design against space debris can be achieved only when a combined approach based on several tools is used. This approach depends on the combined application of advanced numerical methods, specific material models and experimental determination of input parameters for these models. Examples of experimental methods for material characterization are given, covering the range from quasi static to very high strain rates for materials like Nextel and carbon fiber-reinforced materials. Mesh free numerical methods have extraordinary capabilities in the simulation of extreme material behaviour including complete failure with phase changes, combined with shock wave phenomena and the interaction with structural components. In this paper the benefits from combining numerical methods, material modelling and detailed experimental studies for shield design are demonstrated. The following examples are given: (1) Development of a material model for Nextel and Kevlar-Epoxy to enable numerical simulation of hypervelocity impacts on complex heavy protection shields for the International Space Station. (2) The influence of projectile shape on protection performance of Whipple Shields and how experimental problems in accelerating such shapes can be overcome by systematic numerical simulation. (3) The benefits of using metallic foams in "sandwich bumper shields" for spacecraft and how to approach systematic characterization of such materials.
Infant Deaths and Injuries Associated with Wearable Blankets, Swaddle Wraps, and Swaddling
McDonnell, Emily; Moon, Rachel Y.
2014-01-01
Objective To assess risks involved in using wearable blankets, swaddle wraps, and swaddling. Study design Retrospective review of incidents reported to the Consumer Product Safety Commission in 2004–2012. Results 36 incidents involving wearable blankets and swaddle wraps were reviewed, including 10 deaths, 2 injuries, and 12 incidents without injury. The median age at death was 3.5 months; 80% of deaths were attributed to positional asphyxia related to prone sleeping. 70% had additional risk factors, usually soft bedding. Two injuries involved tooth extraction from the zipper. The 12 incidents without injury reported concern for strangulation/suffocation when the swaddle wrap became wrapped around the face/neck, and potential choking hazard when the zipper detached. All 12 incidents involving swaddling in ordinary blankets resulted in death. The median age was 2 months; 58% of deaths were attributed to positional asphyxia related to prone sleeping. 92% involved additional risk factors, most commonly soft bedding. Conclusions Reports of sudden unexpected death in swaddled infants are rare. Risks can be reduced by placing infants supine, and discontinuing swaddling as soon as an infant’s earliest attempts to roll are observed. Risks can be further reduced by removing soft bedding and bumper pads from the sleep environment. When using commercial swaddle wraps, fasteners must be securely attached. PMID:24507866
Tennis injuries: prevention and treatment. A review.
Kulund, D N; McCue, F C; Rockwell, D A; Gieck, J H
1979-01-01
When players are engaged in the sport of tennis, injuries may occur to the eyes, in the neck, to the shoulder and back, arm and elbow, wrist and hand, and feet. The key to prevention and treatment of these injuries is good coaching and a formal stretching and strengthening program. The drooped "tennis shoulder" of professionals and senior tennis players is a natural response to heavy use. Shoulder elevating exercises are useful when soreness is associated. The treatment of tennis elbow includes wrist extensor stretching, isometrics, and light weightlifting. When a player follows this program, injections or counterforce braces are rarely needed. It is important for the player to bring his racket to the examination so that his stroke mechanics and grip can be checked. Wrist soreness in a tennis player may denote a hamate hook fracture. Special radiographic views are needed to discern the fracture and it is treated with a short arm cast and little finger extension splint. Nonunion of a hamate hook requires excision. The calf pain prodrome of "tennis leg" requires rest and then a stretching program. Tennis shoes should have rolled heels and large toe boxes with reinforced toe bumpers. The physician may have to fashion soft inserts for the tennis shoes; arch supports may be insufficient.
Surface protection in bio-shields via a functional soft skin layer: Lessons from the turtle shell.
Shelef, Yaniv; Bar-On, Benny
2017-09-01
The turtle shell is a functional bio-shielding element, which has evolved naturally to provide protection against predator attacks that involve biting and clawing. The near-surface architecture of the turtle shell includes a soft bi-layer skin coating - rather than a hard exterior - which functions as a first line of defense against surface damage. This architecture represents a novel type of bio-shielding configuration, namely, an inverse structural-mechanical design, rather than the hard-coated bio-shielding elements identified so far. In the current study, we used experimentally based structural modeling and FE simulations to analyze the mechanical significance of this unconventional protection architecture in terms of resistance to surface damage upon extensive indentations. We found that the functional bi-layer skin of the turtle shell, which provides graded (soft-softer-hard) mechanical characteristics to the bio-shield exterior, serves as a bumper-buffer mechanism. This material-level adaptation protects the inner core from the highly localized indentation loads via stress delocalization and extensive near-surface plasticity. The newly revealed functional bi-layer coating architecture can potentially be adapted, using synthetic materials, to considerably enhance the surface load-bearing capabilities of various engineering configurations. Copyright © 2017 Elsevier Ltd. All rights reserved.
Transition by head-on collision: mechanically mediated manoeuvres in cockroaches and small robots.
Jayaram, Kaushik; Mongeau, Jean-Michel; Mohapatra, Anand; Birkmeyer, Paul; Fearing, Ronald S; Full, Robert J
2018-02-01
Exceptional performance is often considered to be elegant and free of 'errors' or missteps. During the most extreme escape behaviours, neural control can approach or exceed its operating limits in response time and bandwidth. Here we show that small, rapid running cockroaches with robust exoskeletons select head-on collisions with obstacles to maintain the fastest escape speeds possible to transition up a vertical wall. Instead of avoidance, animals use their passive body shape and compliance to negotiate challenging environments. Cockroaches running at over 1 m or 50 body lengths per second transition from the floor to a vertical wall within 75 ms by using their head like an automobile bumper, mechanically mediating the manoeuvre. Inspired by the animal's behaviour, we demonstrate a passive, high-speed, mechanically mediated vertical transitions with a small, palm-sized legged robot. By creating a collision model for animal and human materials, we suggest a size dependence favouring mechanical mediation below 1 kg that we term the 'Haldane limit'. Relying on the mechanical control offered by soft exoskeletons represents a paradigm shift for understanding the control of small animals and the next generation of running, climbing and flying robots where the use of the body can off-load the demand for rapid sensing and actuation. © 2018 The Authors.
Transition by head-on collision: mechanically mediated manoeuvres in cockroaches and small robots
Mongeau, Jean-Michel; Mohapatra, Anand; Birkmeyer, Paul; Fearing, Ronald S.; Full, Robert J.
2018-01-01
Exceptional performance is often considered to be elegant and free of ‘errors’ or missteps. During the most extreme escape behaviours, neural control can approach or exceed its operating limits in response time and bandwidth. Here we show that small, rapid running cockroaches with robust exoskeletons select head-on collisions with obstacles to maintain the fastest escape speeds possible to transition up a vertical wall. Instead of avoidance, animals use their passive body shape and compliance to negotiate challenging environments. Cockroaches running at over 1 m or 50 body lengths per second transition from the floor to a vertical wall within 75 ms by using their head like an automobile bumper, mechanically mediating the manoeuvre. Inspired by the animal's behaviour, we demonstrate a passive, high-speed, mechanically mediated vertical transitions with a small, palm-sized legged robot. By creating a collision model for animal and human materials, we suggest a size dependence favouring mechanical mediation below 1 kg that we term the ‘Haldane limit’. Relying on the mechanical control offered by soft exoskeletons represents a paradigm shift for understanding the control of small animals and the next generation of running, climbing and flying robots where the use of the body can off-load the demand for rapid sensing and actuation. PMID:29445036
Ghana's army goes into combat readiness against HIV.
1992-01-01
Ghana's professional army of 12,000 men were joined by the national police in launching a campaign of education about AIDS which promotes condom use. The campaign received some funding from USAID and AIDS Tech/Family Health International. 94% of the soldiers had 7 years of education and 95% were married. 47% had never used the condom, 37% used it only occasionally, and only 19% used it regularly. An AIDS Awareness Day was followed up by 3000 posters, 1800 bumper stickers, 1500 T-shirts, 300 press packs, 1000 keychains and a video. Comic books in the local pidgin English idiom also proved popular for promotion. In a social marketing scheme, condoms were made available in barracks, army shops, and canteens for a modest price. The sales of condoms rose from about 500 a month in 1991 to 6000-7000 by January 1992. The army AIDS policy spelled out that HIV positivity will be revealed to the infected soldier. HIV-positive soldIers will not be sent abroad, curtailing the chances of disease transmission. They are kept in active service as long as they are capable of meeting their duties. Nevertheless, this policy hinges on the outcome of the AIDS education campaign whose failure could result in a policy of dismissing HIV-infected soldiers.
NASA Astrophysics Data System (ADS)
Jyoti, Jeevan; Pratap Singh, Bhanu; Chockalingam, Sreekumar; Joshi, Amish G.; Gupta, Tejendra K.; Dhakate, S. R.
2018-04-01
Herein, multiwall carbon nanotubes (MWCNTs), reduced graphene oxide (rGO), graphene oxide-carbon nanotubes (GCNTs) hybrid reinforced acrylonitrile butadiene styrene (ABS) nanocomposites have been prepared by micro twin screw extruder with back flow channel and the effect of different type of fillers on the nanomechanical properties are studied. The combination of both graphene oxide and CNT has enhanced the dispersion in polymer matrix and lower the probability of CNTs aggregation. GCNTs hybrid have been synthesized via novel chemical route and well characterized using Raman spectroscopic technique. The nanoindentation hardness and elastic modulus of GCNTs-ABS hybrid nanocomposites were improved from 211.3 MPa and 4.12 GPa of neat ABS to 298.9 MPa and 6.02 GPa, respectively at 5wt% GCNTs loading. In addition to hardness and elastic modulus, other mechanical properties i.e. plastic index parameter, elastic recovery, ratio of residual displacement after load removal and displacement at the maximum load and plastic deformation energy have also been investigated. These results were correlated with Raman and X-ray photoelectron spectroscopic (XPS) techniques and microstructural characterizations (scanning electron microscopy). Our demonstration would provide guidelines for the fabrication of hard and scratches nanocomposite materials for potential use in, automotive trim components and bumper bars, carrying cases and electronic industries and electromagnetic interference shielding.
NASA Astrophysics Data System (ADS)
Schonberg, William P.
Traditional perforation-resistant wall design for long-duration spacecraft consists of a "bumper" that is placed a small distance away from the main "pressure wall" of a spacecraft compartment or module. This concept has been studied extensively as a means of reducing the perforation threat of hypervelocity projectiles such as meteoroids and orbital debris. If a dual-wall system is employed on an earth-orbiting spacecraft, then a blanket of multi-layer insulation (MLI) will typically be included within the dual-wall system for thermal protection purposes. This paper presents the results of an experimental study in which aluminum dual-wall structures were tested under a variety of high-speed impact conditions to study the effect of MLI thickness and location on perforation resistance. The results presented consist of test-by-test comparisons of the damage sustained by similar dual-wall systems with blanket MLI of various thicknesses and at various locations within the dual-wall systems under similar impact loading conditions. The analyses performed revealed that the placement of the MLI had a significant effect on the ballistic limit of the dual-wall structures considered while reducing the thickness of the MLI by as much as 1/3 did not.
Design of the Cross Section Shape of AN Aluminum Crash Box for Crashworthiness Enhancement of a CAR
NASA Astrophysics Data System (ADS)
Kim, S. B.; Huh, H.; Lee, G. H.; Yoo, J. S.; Lee, M. Y.
This paper deals with the crashworthiness of an aluminum crash box for an auto-body with the various shapes of cross section such as a rectangle, a hexagon and an octagon. First, crash boxes with various cross sections were tested with numerical simulation to obtain the energy absorption capacity and the mean load. In case of the simple axial crush, the octagon shape shows higher mean load and energy absorption than the other two shapes. Secondly, the crash boxes were assembled to a simplified auto-body model for the overall crashworthiness. The model consists of a bumper, crash boxes, front side members and a sub-frame representing the behavior of a full car at the low speed impact. The analysis result shows that the rectangular cross section shows the best performance as a crash box which deforms prior to the front side member. The hexagonal and octagonal cross sections undergo torsion and local buckling as the width of cross section decreases while the rectangular cross section does not. The simulation result of the rectangular crash box was verified with the experimental result. The simulation result shows close tendency in the deformed shape and the load-displacement curve to the experimental result.
Biofidelity Evaluation of a Prototype Hybrid III 6 Year-Old ATD Lower Extremity.
Boucher, Laura C; Bing, Julie; Bolte, John H
2016-09-01
Incomplete instrumentation and a lack of biofidelity in the extremities of the 6 year-old anthropomorphic test device (ATD) pose challenges when studying regions of the body known to interact with the vehicle interior. This study sought to compare a prototype Hybrid III 6 year-old ATD leg (ATD-LE), with a more biofidelic ankle and tibia load cell, to previously collected child volunteer data and to the current Hybrid III 6 year-old ATD (HIII). Anthropometry, range of motion (ROM), and stiffness measurements were taken, along with a dynamic evaluation of the ATD-LE using knee-bolster airbag (KBA) test scenarios. Anthropometry values were similar in eight of twelve measurements. Total ankle ROM was improved in the ATD-LE with no bumper compared to the HIII. The highest tibia moments and tibia index values were recorded in KBA scenarios when the toes were positioned in contact with the dashboard prior to airbag deployment, forcing the ankle into axial loading and dorsiflexion. While improvements in the biofidelity of the ATD-LE are still necessary, the results of this study are encouraging. Continued advancement of the 6 year-old ATD ankle is necessary to provide a tool to directly study the behavior of the leg during a motor vehicle crash.
The composition and plasma signature of a large dust impact on the Giotto spacecraft
NASA Technical Reports Server (NTRS)
Goldstein, R.; Goldstein, B. E.; Balsiger, H.; Coates, A. J.; Curdt, W.
1991-01-01
At about 14,800 km from the Comet Halley nucleus, on the inbound leg, at least six of the sensors onboard the Giotto spacecraft observed an unusual, brief (about 30 to 500 ms) event: the ion-mass spectrometer data show a brief flow of energetic (up to several hundred electron volts) plasma consisting of protons, water group, and heavier ions. The Johnstone plasma analyzer data show a short burst of plasma, while the dust impact detector system data show an impact event in four of its detectors. The magnetometer signature of the event shows two brief dips in the field. The sudden change in the spacecraft attitude and spin rate observed by the camera at that same time has been interpreted as the result of a large (5 mg or more) dust-particle impact on the front bumper shield of the spacecraft. In addition, at about the same time the spacecraft star-tracker suffered damage. The report combines direct measurements of the composition and dynamics of a dust-impact plasma cloud, the dust particle mass, and the location of the impact on the spacecraft. Analysis of the data indicate that the impacting particle was water or ice-bearing, possibly loosely compared, and was composed of one or more of: carbon, nitrogen, and silicon.
Metal flow of a tailor-welded blank in deep drawing process
NASA Astrophysics Data System (ADS)
Yan, Qi; Guo, Ruiquan
2005-01-01
Tailor welded blanks were used in the automotive industry to consolidate parts, reduce weight, and increase safety. In recent years, this technology was developing rapidly in China. In Chinese car models, tailor welded blanks had been applied in a lot of automobile parts such as rail, door inner, bumper, floor panel, etc. Concerns on the properties of tailor welded blanks had become more and more important for automobile industry. A lot of research had shown that the strength of the welded seam was higher than that of the base metal, such that the weld failure in the aspect of strength was not a critical issue. However, formability of tailor welded blanks in the stamping process was complex. Among them, the metal flow of tailor welded blanks in the stamping process must be investigated thoroughly in order to reduce the scrap rate during the stamping process in automobile factories. In this paper, the behavior of metal flow for tailor welded blanks made by the laser welding process with two types of different thickness combinations were studied in the deep drawing process. Simulations and experiment verification of the movement of weld line for tailor welded blanks were discussed in detail. Results showed that the control on the movement of welded seam during stamping process by taking some measures in the aspect of blank holder was effective.
NASA Technical Reports Server (NTRS)
Levin, George M.; Christiansen, Eric L.
1997-01-01
The pre-flight predictions and postflight assessments carried out in relation to a series of Space Shuttle missions are reviewed, and data are presented for the meteoroid and orbital debris damage observed on the Hubble Space Telescope during the 1994 Hubble repair mission. Pre-flight collision risk analyses are carried out prior to each mission, and in the case of an unacceptable risk, the mission profile is altered until the risk is considered to be acceptable. The NASA's BUMPER code is used to compute the probability of damage from debris and meteoroid particle impacts based on the Poisson statistical model for random events. The penetration probability calculation requires information concerning the geometry of the critical systems, the penetration resistance and mission profile parameters. Following each flight, the orbiter is inspected for meteoroid and space debris damage. The emphasis is on areas such as the radiator panels, the windows and the reinforced carbon-carbon structures on the leading wing edges and on the nose cap. The contents of damage craters are analyzed using a scanning electron microscope to determine the nature and origin of the impactor. Hypervelocity impact tests are often performed to simulate the observed damage and to estimate the nature of the damaging particles. The number and type of damage observed provides information concerning the orbital debris environment.
Stochastic optimal preview control of a vehicle suspension
NASA Astrophysics Data System (ADS)
Marzbanrad, Javad; Ahmadi, Goodarz; Zohoor, Hassan; Hojjat, Yousef
2004-08-01
Stochastic optimal control of a vehicle suspension on a random road is studied. The road roughness height is modelled as a filtered white noise stochastic process and a four-degree-of-freedom half-car model is used in the analysis. It is assumed that a sensor is mounted in the front bumper that measures the road irregularity at some distances in the front of the vehicle. Two other sensors also measure relative velocities of the vehicle body with respect to the unsprung masses in the vehicle suspension spaces. All measurements are assumed to be conducted in a noisy environment. The state variables of the vehicle system are estimated using a method similar to the Kalman filter. The suspension system is optimized by minimizing the performance index containing the mean-square values of body accelerations (including effects of heave and pitch), tire deflections and front and rear suspension rattle spaces. The effect of delay between front and rear wheels is included in the analysis. For stochastic active control with and without preview, the suspension performance and the power demand are evaluated and compared with those of the passive system. The results show that the inclusion of time delay between the front and rear axles and the preview information measured by the sensor mounted on the vehicle improves all aspects of the suspension performance, while reducing the energy consumption.
A rapid assessment survey of invasive species of macrobenthic invertebrates in Korean waters
NASA Astrophysics Data System (ADS)
Park, Chul; Kim, Sung-Tae; Hong, Jae-Sang; Choi, Keun-Hyung
2017-09-01
Introduced species are a growing and imminent threat to living marine resources in parts of the world's oceans. The present study is a rapid assessment survey of invasive macrobenthic invertebrate species in Korean ports. We surveyed over 40 ports around Korea during the period of May 2010 March 2013. Among the sampling sites were concrete walls, docks and associated floats, bumpers, tires, and ropes which might harbor non-native species. We found 15 invasive species as follows: one Sponge, two Bryozoans, three Mollusks, one Polychaete, four Cirripedes, and four Ascidians. Three morphologically similar species, namely X. atrata, M. galloprovincialis, and X. securis were further examined for distinctions in their morphology. Although they could be reasonably distinguished based on shell shapes, significant overlap was noted so that additional analysis may be required to correctly distinguish them. Although many of the introduced species have already spread to all three coastal areas, newly arrived invasive species showed a relatively restricted range, with a serpulid polychaete Ficopomatus enigmaticus and a mytilid bivalve Xenostrobus securis found only at a few sites on the East Coast. An exception is for Balanus perforatus, which has rapidly colonized the East coast of Korea following its introduction into the region. Successful management of invasive macrobenthic invertebrates should be established in order to contain the spread of these newly arrived species.
NASA Technical Reports Server (NTRS)
Rhatigan, Jennifer L.; Christiansen, Eric L.; Fleming, Michael L.
1990-01-01
A great deal of experimentation and analysis was performed to quantify penetration thresholds of components which will experience orbital debris impacts. Penetration was found to depend upon mission specific parameters such as orbital altitude, inclination, and orientation of the component; and upon component specific parameters such as material, density and the geometry particular to its shielding. Experimental results are highly dependent upon shield configuration and cannot be extrapolated with confidence to alternate shield configurations. Also, current experimental capabilities are limited to velocities which only approach the lower limit of predicted orbital debris velocities. Therefore, prediction of the penetrating particle size for a particular component having a complex geometry remains highly uncertain. An approach is described which was developed to assess on-orbit survivability of the solar dynamic radiator due to micrometeoroid and space debris impacts. Preliminary analyses are presented to quantify the solar dynamic radiator survivability, and include the type of particle and particle population expected to defeat the radiator bumpering (i.e., penetrate a fluid flow tube). Results of preliminary hypervelocity impact testing performed on radiator panel samples (in the 6 to 7 km/sec velocity range) are also presented. Plans for further analyses and testing are discussed. These efforts are expected to lead to a radiator design which will perform to requirements over the expected lifetime.
Treatment of Class II malocclusion with mandibular skeletal anchorage.
Cakir, Ezgi; Malkoç, Siddik; Kirtay, Mustafa
2017-06-01
The aim of this case report was to present the dentofacial changes obtained with bone anchorage in a Class II patient with moderate to severe crowding. A boy, aged 14.5 years, with a dolichofacial type, convex profile, and skeletal and dental Class II relationships was examined. After evaluation, functional treatment with bone anchorage and 4 first premolar extractions was decided as the treatment approach. Miniplates were placed on the buccal shelves of the mandibular third molars. The hook of the anchor was revealed from the first molar level. After surgery, the 4 first premolars were extracted to retract the protrusive mandibular incisors. The maxillary and mandibular first molars were banded, and a lip bumper was inserted to apply elastics and to help distalize the maxillary first molars. Orthodontic forces of 300 to 500 g were applied immediately after placement, originating from the miniscrews to the hooks of the appliance to advance the mandible. After 20 months of treatment, the patient had a dental and skeletal Class I relationship, the mandible was advanced, the maxilla was restrained, and overjet was decreased. The combination of a bone anchor, Class II elastics, and an inner bow is a promising alternative to functional treatment, along with extractions, in Class II patients. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.
"Sniffer"—a novel tool for chasing vehicles and measuring traffic pollutants
NASA Astrophysics Data System (ADS)
Pirjola, L.; Parviainen, H.; Hussein, T.; Valli, A.; Hämeri, K.; Aaalto, P.; Virtanen, A.; Keskinen, J.; Pakkanen, T. A.; Mäkelä, T.; Hillamo, R. E.
To measure traffic pollutants with high temporal and spatial resolution under real conditions a mobile laboratory was designed and built in Helsinki Polytechnic in close co-operation with the University of Helsinki. The equipment of the van provides gas phase measurements of CO and NO x, number size distribution measurements of fine and ultrafine particles by an electrical low pressure impactor, an ultrafine condensation particle counter and a scanning mobility particle sizer. Two inlet systems, one above the windshield and the other above the bumper, enable chasing of different type of vehicles. Also, meteorological and geographical parameters are recorded. This paper introduces the construction and technical details of the van, and presents data from the measurements performed during an LIPIKA campaign on the highway in Helsinki. Approximately 90% of the total particle number concentration was due to particles smaller than 50 nm on the highway in Helsinki. The peak concentrations exceeded often 200,000 particles cm -3 and reached sometimes a value of 10 6 cm -3. Typical size distribution of fine particles possessed bimodal structure with the modal mean diameters of 15-20 nm and ˜150 nm. Atmospheric dispersion of traffic pollutions were measured by moving away from the highway along the wind direction. At a distance of 120-140 m from the source the concentrations were diluted to one-tenth from the values at 9 m from the source.
Optical fiber sensors embedded in flexible polymer foils
NASA Astrophysics Data System (ADS)
van Hoe, Bram; van Steenberge, Geert; Bosman, Erwin; Missinne, Jeroen; Geernaert, Thomas; Berghmans, Francis; Webb, David; van Daele, Peter
2010-04-01
In traditional electrical sensing applications, multiplexing and interconnecting the different sensing elements is a major challenge. Recently, many optical alternatives have been investigated including optical fiber sensors of which the sensing elements consist of fiber Bragg gratings. Different sensing points can be integrated in one optical fiber solving the interconnection problem and avoiding any electromagnetical interference (EMI). Many new sensing applications also require flexible or stretchable sensing foils which can be attached to or wrapped around irregularly shaped objects such as robot fingers and car bumpers or which can even be applied in biomedical applications where a sensor is fixed on a human body. The use of these optical sensors however always implies the use of a light-source, detectors and electronic circuitry to be coupled and integrated with these sensors. The coupling of these fibers with these light sources and detectors is a critical packaging problem and as it is well-known the costs for packaging, especially with optoelectronic components and fiber alignment issues are huge. The end goal of this embedded sensor is to create a flexible optical sensor integrated with (opto)electronic modules and control circuitry. To obtain this flexibility, one can embed the optical sensors and the driving optoelectronics in a stretchable polymer host material. In this article different embedding techniques for optical fiber sensors are described and characterized. Initial tests based on standard manufacturing processes such as molding and laser structuring are reported as well as a more advanced embedding technique based on soft lithography processing.
Decisions of black parents about infant bedding and sleep surfaces: a qualitative study.
Ajao, Taiwo I; Oden, Rosalind P; Joyner, Brandi L; Moon, Rachel Y
2011-09-01
The goal of this qualitative study was to examine factors influencing decisions by black parents regarding use of soft bedding and sleep surfaces for their infants. We conducted focus groups and individual interviews with black mothers of lower and higher socioeconomic status (SES). Mothers were asked about many infant care practices, including sleep surface and bedding. Eighty-three mothers were interviewed, 73 (47 lower and 26 higher SES) in focus groups and 10 (7 lower and 3 higher SES) in individual interviews. The primary reason for using soft surfaces was infant comfort. Parents perceived that infants were uncomfortable if the surface was not soft. Many parents also interpreted "firm sleep surface" to mean taut; they were comfortable with and believed that they were following recommendations for a firm sleep surface when they placed pillows/blankets on the mattress as long as a sheet was pulled tautly over the pillows/blankets. The primary reasons for using soft bedding (including bumper pads) were comfort, safety, and aesthetics. In addition to using bedding to soften sleep surfaces, bedding was used to prevent infant rollover and falls, particularly for infants sleeping on a bed or sofa. Some parents used soft bedding to create an attractive space for the infant. Many black parents believe that soft bedding will keep their infant safe and comfortable. There is much misunderstanding about the meaning of a "firm" sleep surface. Additional educational messages apparently are needed to change parental perceptions and practices.
Mathematical model for studying cyclist kinematics in vehicle-bicycle frontal collisions
NASA Astrophysics Data System (ADS)
Condrea, OA; Chiru, A.; Chiriac, RL; Vlase, S.
2017-10-01
For the development of effective vehicle related safety solutions to improve cyclist protection, kinematic predictions are essential. The objective of the paper was the elaboration of a simple mathematical model for predicting cyclist kinematics, with the advantage of yielding simple results for relatively complicated impact situations. Thus, the use of elaborated math software is not required and the calculation time is shortened. The paper presents a modelling framework to determine cyclist kinematic behaviour for the situations in which a M1 category vehicle frontally hits the rear part of a bicycle. After the primary impact between the vehicle front bumper and the bicycle, the cyclist hits the vehicle’s bonnet, the windscreen or both the vehicle’s bonnet and the windscreen in short succession. The head-windshield impact is often the most severe impact, causing serious and potentially lethal injuries. The cyclist is represented by a rigid segment and the equations of motion for the cyclist after the primary impact are obtained by applying Newton’s second law of motion. The impact time for the contact between the vehicle and the cyclist is yielded afterwards by formulating and intersecting the trajectories for two points positioned on the cyclist’s head/body and the vehicle’s windscreen/bonnet while assuming that the cyclist’s equations of motion after the primary impact remain the same. Postimpact kinematics for the secondary impact are yielded by applying linear and angular momentum conservation laws.
Shock reliability analysis and improvement of MEMS electret-based vibration energy harvesters
NASA Astrophysics Data System (ADS)
Renaud, M.; Fujita, T.; Goedbloed, M.; de Nooijer, C.; van Schaijk, R.
2015-10-01
Vibration energy harvesters can serve as a replacement solution to batteries for powering tire pressure monitoring systems (TPMS). Autonomous wireless TPMS powered by microelectromechanical system (MEMS) electret-based vibration energy harvester have been demonstrated. The mechanical reliability of the MEMS harvester still has to be assessed in order to bring the harvester to the requirements of the consumer market. It should survive the mechanical shocks occurring in the tire environment. A testing procedure to quantify the shock resilience of harvesters is described in this article. Our first generation of harvesters has a shock resilience of 400 g, which is far from being sufficient for the targeted application. In order to improve this aspect, the first important aspect is to understand the failure mechanism. Failure is found to occur in the form of fracture of the device’s springs. It results from impacts between the anchors of the springs when the harvester undergoes a shock. The shock resilience of the harvesters can be improved by redirecting these impacts to nonvital parts of the device. With this philosophy in mind, we design three types of shock absorbing structures and test their effect on the shock resilience of our MEMS harvesters. The solution leading to the best results consists of rigid silicon stoppers covered by a layer of Parylene. The shock resilience of the harvesters is brought above 2500 g. Results in the same range are also obtained with flexible silicon bumpers, which are simpler to manufacture.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steffens, H.D.; Kern, H.; Janczak, J.
The potential benefits and the current state-of-the-art in MMCs will be presented through a discussion of their processing and related aspects. The advantages and limitations of most common manufacturing techniques of fiber reinforced metals, e.g. realized property potential and commercial possibilities, will be outlined. The emphasis will be given on novel powder metallurgy techniques such as rapid solidification (e.g. atomization techniques and plasma processes) and new materials systems (e.g. intermetallic matrix composites). The technical barriers which prevent the transition of MMCs from aerospace to a wider range of applications will be highlighted, Special attention will be drawn to the relationmore » between processing parameters, fiber-matrix interface and composite properties. The challenge of composite modeling and design as well as interface controlling for successful processing utilization of MMCs will be mentioned. The benefits of use of computer techniques (databases, simulations, knowledge based systems) to aid the composite design and process control (fuzzy logic) will be shown on several examples. The technical possibilities of adaptation of interface tailoring approaches from the PMC area such as graded interphase or rubber-bumper interface will be studied. In addition, on the basis of recent forecasts by different experts on composite materials the question of the MMCs future will be discussed. Have they a chance in the next few years to meet the requirements of successful commercial applications, especially those of clients? The problems which have to be solved and options for solution will be dealt with.« less
How to decrease pedestrian injuries: conceptual evolutions starting from 137 crash tests.
Thollon, Lionel; Jammes, Christian; Behr, Michel; Arnoux, Pierre-Jean; Cavallero, Claude; Brunet, Christian
2007-02-01
The improvement of vulnerable users' protection has become an essential objective for our society. Injury assessments observed in clinical traumatology have led researchers and manufacturers to understand the mechanisms involved and to design safe vehicles (to reduce the severity of pedestrian injuries). In all, 137 crash tests between 1979 and 2004 with postmortal human subjects (PMHS) were performed at the Laboratory of Applied Biomechanics to access pedestrian protection. A retrospective analysis of these experimental tests, pedestrian/car impacts (full scale or subsystems), performed at the laboratory is thus proposed. This document focuses on injury mechanisms investigation on the evolution of the experimental approach, as well as on the vehicles' technological improvements performed by car manufacturers. The analysis of experimental results (injury assessment, kinematics, vehicle deformations, etc.) shows the complexity and variety of injury mechanisms. The injury assessment shows the need to improve lower-limb joints protection, as well as head and spine segments, because of the difficulties of surgical repair of these injuries. Experimental tests contribute to evaluate the automobile safety evolution in the field of pedestrian protection. The main induced car improvements concern considerable efforts on vehicle material behavior and their capacity to dissipate energy during shocks (replacement of the convex rigid bumpers by deformable structures, modification of the windscreen structure). They also concern the suppression of all aggressive structures for the pedestrian (spare wheel initially placed on the front part of the vehicle, protection of the heels of windscreen wiper, etc.).
Estimating Consequences of MMOD Penetrations on ISS
NASA Technical Reports Server (NTRS)
Evans, H.; Hyde, James; Christiansen, E.; Lear, D.
2017-01-01
The threat from micrometeoroid and orbital debris (MMOD) impacts on space vehicles is often quantified in terms of the probability of no penetration (PNP). However, for large spacecraft, especially those with multiple compartments, a penetration may have a number of possible outcomes. The extent of the damage (diameter of hole, crack length or penetration depth), the location of the damage relative to critical equipment or crew, crew response, and even the time of day of the penetration are among the many factors that can affect the outcome. For the International Space Station (ISS), a Monte-Carlo style software code called Manned Spacecraft Crew Survivability (MSCSurv) is used to predict the probability of several outcomes of an MMOD penetration-broadly classified as loss of crew (LOC), crew evacuation (Evac), loss of escape vehicle (LEV), and nominal end of mission (NEOM). By generating large numbers of MMOD impacts (typically in the billions) and tracking the consequences, MSCSurv allows for the inclusion of a large number of parameters and models as well as enabling the consideration of uncertainties in the models and parameters. MSCSurv builds upon the results from NASA's Bumper software (which provides the probability of penetration and critical input data to MSCSurv) to allow analysts to estimate the probability of LOC, Evac, LEV, and NEOM. This paper briefly describes the overall methodology used by NASA to quantify LOC, Evac, LEV, and NEOM with particular emphasis on describing in broad terms how MSCSurv works and its capabilities and most significant models.
Future direction of direct writing
NASA Astrophysics Data System (ADS)
Kim, Nam-Soo; Han, Kenneth N.
2010-11-01
Direct write technology using special inks consisting of finely dispersed metal nanoparticles in liquid is receiving an undivided attention in recent years for its wide range of applicability in modern electronic industry. The application of this technology covers radio frequency identification-tag (RFID-tag), flexible-electronics, organic light emitting diodes (OLED) display, e-paper, antenna, bumpers used in flip-chip, underfilling, frit, miniresistance applications and biological uses, artificial dental applications and many more. In this paper, the authors have reviewed various direct write technologies on the market and discussed their advantages and shortfalls. Emphasis has given on microdispensing deposition write (MDDW), maskless mesoscale materials deposition (M3D), and ink-jet technologies. All of these technologies allow printing various patterns without employing a mask or a resist with an enhanced speed with the aid of computer. MDDW and M3D are capable of drawing patterns in three-dimension and MDDW, in particular, is capable of writing nanoinks with high viscosity. However, it is still far away for direct write to be fully implemented in the commercial arena. One of the hurdles to overcome is in manufacturing conductive inks which are chemically and physically stable, capable of drawing patterns with acceptable conductivity, and also capable of drawing patterns with acceptable adhesiveness with the substrates. The authors have briefly discussed problems involved in manufacturing nanometal inks to be used in various writing devices. There are numerous factors to be considered in manufacturing such inks. They are reducing agents, concentrations, oxidation, compact ability allowing good conductivity, and stability in suspension.
Ramwell, A; Rice-Oxley, M; Bond, A; Simson, J N L
2011-10-01
Bowel dysfunction results in a major lifestyle disruption for many patients with severe central neurologic disease. Percutaneous endoscopic sigmoid colostomy for irrigation (PESCI) allows antegrade irrigation of the distal large bowel for the management of both incontinence and constipation. This study prospectively assessed the safety and efficacy of PESCI. A PESCI tube was placed endoscopically in the sigmoid colon of 25 patients to allow antegrade irrigation. Control of constipation and fecal incontinence was improved for 21 (84%) of the 25 patients. These patients were followed up for 6-83 months (mean, 43 months), with long-term success for 19 (90%) of the patients. No PESCI had to be removed for technical reasons or for PESCI complications. Late removal of the PESCI was necessary for 2 of the 21 patients. A modified St. Marks Fecal Incontinence Score to assess bowel function before and after PESCI showed a highly significant improvement (P < 0.0001). There were no procedure-related deaths. Complications included minor sepsis at the initial PESCI tube site in four patients and bumper migration in two patients, but there were no complications related to the button device. This study showed that PESCI is a simple, safe, and effective technique for distal antegrade irrigation in the management bowel dysfunction for selected patients with central neurologic disease. A successful PESCI is very likely to continue functioning satisfactorily for a long time without technical problems or local complications.
Predicting the Consequences of MMOD Penetrations on the International Space Station
NASA Technical Reports Server (NTRS)
Hyde, James; Christiansen, E.; Lear, D.; Evans
2018-01-01
The threat from micrometeoroid and orbital debris (MMOD) impacts on space vehicles is often quantified in terms of the probability of no penetration (PNP). However, for large spacecraft, especially those with multiple compartments, a penetration may have a number of possible outcomes. The extent of the damage (diameter of hole, crack length or penetration depth), the location of the damage relative to critical equipment or crew, crew response, and even the time of day of the penetration are among the many factors that can affect the outcome. For the International Space Station (ISS), a Monte-Carlo style software code called Manned Spacecraft Crew Survivability (MSCSurv) is used to predict the probability of several outcomes of an MMOD penetration-broadly classified as loss of crew (LOC), crew evacuation (Evac), loss of escape vehicle (LEV), and nominal end of mission (NEOM). By generating large numbers of MMOD impacts (typically in the billions) and tracking the consequences, MSCSurv allows for the inclusion of a large number of parameters and models as well as enabling the consideration of uncertainties in the models and parameters. MSCSurv builds upon the results from NASA's Bumper software (which provides the probability of penetration and critical input data to MSCSurv) to allow analysts to estimate the probability of LOC, Evac, LEV, and NEOM. This paper briefly describes the overall methodology used by NASA to quantify LOC, Evac, LEV, and NEOM with particular emphasis on describing in broad terms how MSCSurv works and its capabilities and most significant models.
A Plasma Drag Hypervelocity Particle Accelerator (HYPER)
NASA Technical Reports Server (NTRS)
Best, Steve R.; Rose, M. Frank
1998-01-01
Current debris models are able to predict the growth of the space debris problem and suggest that spacecraft must employ armor or bumper shields for some orbital altitudes now and that the problem will become worse as a function of time. The practical upper limit to the velocity distribution is on the order of 40 km/s and is associated with the natural environment. The velocity distribution of the man-made component peaks at 9-10 km/s with maximum velocity in the 14-16 km/s range. Experience in space has verified that the "high probability of impact" particles are in the microgram to milligram range. These particles can have very significant effects on coatings, insulators, and thin metallic layers. The surface of thick materials becomes pitted and the local debris component is enhanced by ejecta from the impact events. In this paper, the HYPER facility is described which produces a reasonable simulation of the man-made space debris spectrum in a controlled environment. The facility capability is discussed in terms of drive geometry, energetics, velocity distribution, diagnostics, and projectile/debris loading. The facility has been used to study impact phenomena on Space Station Freedom's solar array structure, the calibration of space debris collectors, other solar array materials, potential structural materials for use in space, electrical breakdown in the space environment, and as a means of clarifying or duplicating the impact phenomena on surfaces which have been exposed in space.
Baker, Bryan C; Nolan, Joseph M; O'Neill, Brian; Genetos, Alexander P
2008-01-01
Passenger vehicles are designed to absorb crash energy in frontal crashes through deformation or crush of energy-absorbing structures forward of the occupant compartment. In collisions between cars and light trucks (i.e., pickups and SUVs), however, the capacity of energy-absorption structures may not be fully utilized because mismatches often exist between the heights of these structures in the colliding vehicles. In 2003 automakers voluntarily committed to new design standards aimed at reducing the height mismatches between cars and light trucks. By September 2009 all new light trucks will have either the primary front structure (typically the frame rails) or a secondary structure connected to the primary structure low enough to interact with the primary structures in cars, which for most cars is about the height of the front bumper. To estimate the overall benefit of the voluntary commitment, the real-world crash experience of light trucks already meeting the height-matching criteria was compared with that of light trucks not meeting the criteria for 2000-2003 model light trucks in collisions with passenger cars during calendar years 2001-2004. The estimated benefits of lower front energy-absorbing structure were a 19 percent reduction (p<0.05) in fatality risk to belted car drivers in front-to-front crashes with light trucks and a 19 percent reduction (p<0.05) in fatality risk to car drivers in front-to-driver-side crashes with light trucks.
Nocturnal Video Assessment of Infant Sleep Environments
Batra, Erich K.; Teti, Douglas M.; Schaefer, Eric W.; Neumann, Brooke A.; Meek, Elizabeth A.
2016-01-01
BACKGROUND AND OBJECTIVE: Reports describing factors associated with sleep-related infant death rely on caregiver report or postmortem findings. We sought to determine the frequency of environmental risk factors by using nocturnal sleep videos of infants. METHODS: Healthy, term newborns were recruited for a parent study examining the role of parenting in the development of nighttime infant sleep patterns. For 1 night at ages 1, 3, and 6 months, video recordings were conducted within family homes. Videos were coded for sudden infant death syndrome risk factors in post hoc secondary analyses after the parent study was completed. RESULTS: Among 160 one-month-olds, initially 21% were placed to sleep on nonrecommended sleep surfaces and 14% were placed nonsupine; 91% had loose/nonapproved items on their sleep surface, including bedding, bumper pads, pillows, stuffed animals, and sleep positioners. Among 151 three-month-olds, 10% were initially placed on a nonrecommended sleep surface, 18% were placed nonsupine, and 87% had potentially hazardous items on their sleep surface. By 6 months, 12% of the 147 infants initially slept on a nonrecommended surface, 33% were placed to bed nonsupine, and 93% had loose/nonrecommended items on their surface. At 1, 3, and 6 months, 28%, 18%, and 12% changed sleep locations overnight, respectively, with an increased likelihood of bed-sharing and nonsupine position at the second location at each time point. CONCLUSIONS: Most parents, even when aware of being recorded, placed their infants in sleep environments with established risk factors. If infants were moved overnight, the second sleep environment generally had more hazards. PMID:27527797
Experimental research on pedestrian lower leg impact
NASA Astrophysics Data System (ADS)
Constantin, B. A.; Iozsa, D. M.; Stan, C.
2017-10-01
The present paper is centred on the research of deceleration measured at the level of the lower leg during a pedestrian impact in multiple load cases. Basically, the used methodology for physical test setup is similar to EuroNCAP and European Union regulatory requirements. Due cost reduction reasons, it was not used a pneumatic system in order to launch the lower leg impactor in the direction of the vehicle front-end. During the test it was used an opposite solution, namely the vehicle being in motion, aiming the standstill lower leg impactor. The impactor has similar specifications to those at EU level, i.e. dimensions, materials, and principle of measurement of the deceleration magnitude. Therefore, all the results obtained during the study comply with the requirements of both EU regulation and EuroNCAP. As a limitation, due to unavailability of proper sensors in the equipment of the lower leg impactor, that could provide precise results, the bending angle, the shearing and the detailed data at the level of knee ligaments were not evaluated. The knee joint should be improved for future studies as some bending angles observed during the post processing of several impact video files were too high comparing to other studies. The paper highlights the first pedestrian impact physical test conducted by the author, following an extensive research in the field. Deceleration at the level of pedestrian knee can be substantially improved by providing enough volume between the bumper fascia and the front-end structure and by using pedestrian friendly materials for shock absorbers, such as foams.
Gill, Pooria; Ranjbar, Bijan; Saber, Reza; Khajeh, Khosro; Mohammadian, Mehdi
2011-07-01
Cauliflower-like DNAs are stem-loop DNAs that are fabricated periodically in inverted repetitions from deoxyribonucleic acid phosphates (dNTPs) by loop-mediated isothermal amplification (LAMP). Cauliflower-like DNAs have ladder-shape behaviors on gel electrophoresis, and increasing the time of LAMP leads to multiplying the repetitions, stem-loops, and electrophoretic bands. Cauliflower-like DNAs were fabricated via LAMP using two loop primers, two bumper primers, dNTPs, a λ-phage DNA template, and a Bst DNA polymerase in 75- and 90-min periods. These times led to manufacturing two types of cauliflower-like DNAs with different contents of inverted repetitions and stem-loops, which were clearly indicated by two comparable electrophoresis patterns in agarose gel. LAMP-fabricated DNAs and natural dsB-DNA (salmon genomic DNA) were dialyzed in Gomori phosphate buffer (10 mM, pH 7.4) to be isolated from salts, nucleotides, and primers. Dialyzed DNAs were studied using UV spectroscopy, circular dichroism spectropolarimetry, and fluorescence spectrophotometry. Structural analyses indicated reduction of the molecular ellipticity and extinction coefficients in comparison with B-DNA. Also, cauliflower-like DNAs demonstrated less intrinsic and more extrinsic fluorescence in comparison with natural DNA. The overwinding and lengthening of the cauliflower-like configurations of LAMP DNAs led to changes in physical parameters of this type of DNA in comparison with natural DNA. The results obtained introduced new biomolecular characteristics of DNA macromolecules fabricated within a LAMP process and show the effects of more inverted repeats and stem-loops, which are manufactured by lengthening the process.
NASA Astrophysics Data System (ADS)
Zhang, Hongshen; Chen, Ming
2015-11-01
The recovery and utilization of automotive plastics are a global concern because of the increasing number of end-of-life vehicles. In-depth studies on technologies for the removal of coatings from automotive plastics can contribute to the high value-added levels of the recycling and utilization of automotive plastic. The liquid waste generated by removing chemical paint by using traditional methods is difficult to handle and readily produces secondary pollution. Therefore, new, clean, and highly efficient techniques of paint removal must be developed. In this article, a method of coating removal from passenger-vehicle plastics was generated based on high-pressure water jet technology to facilitate the recycling of these plastics. The established technology was theoretically analyzed, numerically simulated, and experimentally studied. The high-pressure water jet equipment for the removal of automotive-plastic coatings was constructed through research and testing, and the detailed experiments on coating removal rate were performed by using this equipment. The results showed that high-pressure water jet technology can effectively remove coatings on the surfaces of passenger-vehicle plastics. The research also revealed that the coating removal rate increased as jet pressure ( P) increased and then decreased when jet moving speed ( Vn) increased. The rate decreased as the distance from nozzle to work piece ( S nw ) and the nozzle angle ( Φ) increased. The mathematical model for the rate of removal of coatings from bumper surfaces by water jet was derived based on the experiment data and can effectively predict coating removal rate under different operating conditions.
Hypervelocity impact facility for simulating materials exposure to impact by space debris
NASA Technical Reports Server (NTRS)
Rose, M. F.; Best, S.; Chaloupka, T.; Stephens, B.; Crawford, G.
1993-01-01
As a result of man's venturing into space, the local debris contributed by his presence exceeds, at some orbital altitudes, that of the natural component. Man's contribution ranges from fuel residue to large derelect satellites that weigh many kilograms. Current debris models are able to predict the growth of the problem and suggest that spacecraft must employ armor or bumper shields for some orbital altitudes now, and that, the problem will become worse as a function of time. The practical upper limit to the velocity distribution is on the order of 40 km/s and is associated with the natural environment. The maximum velocity of the man-made component is in the 14-16 km/s range. The Long Duration Exposure Facility (LDEF) has verified that the 'high probability of impact' particles are in the microgram to milligram range. These particles can have significant effects on coatings, insulators, and thin metallic layers. The surface of thick materials becomes pitted and the local debris component is enhanced by ejecta from the debris spectrum in a controlled environment. The facility capability is discussed in terms of drive geometry, energetics, velocity distribution, diagnostics, and projectile/debris loading. The facility is currently being used to study impact phenomena on Space Station Freedom's solar array structure, other solar array materials, potential structural materials for use in the station, electrical breakdown in the space environment, and as a means of clarifying or duplicating the impact phenomena on the LDEF surfaces. The results of these experiments are described in terms of the mass/velocity distribution incident on selected samples, crater dynamics, and sample geometry.
A vibro-haptic human-machine interface for structural health monitoring
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mascarenas, David; Plont, Crystal; Brown, Christina
The structural health monitoring (SHM) community’s goal has been to endow physical systems with a nervous system not unlike those commonly found in living organisms. Typically the SHM community has attempted to do this by instrumenting structures with a variety of sensors, and then applying various signal processing and classification procedures to the data in order to detect the presence of damage, the location of damage, the severity of damage, and to estimate the remaining useful life of the structure. This procedure has had some success, but we are still a long way from achieving the performance of nervous systemsmore » found in biology. This is primarily because contemporary classification algorithms do not have the performance required. In many cases expert judgment is superior to automated classification. This work introduces a new paradigm. We propose interfacing the human nervous system to the distributed sensor network located on the structure and developing new techniques to enable human-machine cooperation. Results from the field of sensory substitution suggest this should be possible. This study investigates a vibro-haptic human-machine interface for SHM. The investigation was performed using a surrogate three-story structure. The structure features three nonlinearity-inducing bumpers to simulate damage. Accelerometers are placed on each floor to measure the response of the structure to a harmonic base excitation. The accelerometer measurements are preprocessed. As a result, the preprocessed data is then encoded encoded as a vibro-tactile stimulus. Human subjects were then subjected to the vibro-tactile stimulus and asked to characterize the damage in the structure.« less
The static breaking technique for sustainable and eco-environmental coal mining.
Bing-yuan, Hao; Hui, Huang; Zi-jun, Feng; Kai, Wang
2014-01-01
The initiating explosive devices are prohibited in rock breaking near the goaf of the highly gassy mine. It is effective and applicable to cracking the hard roof with static cracking agent. By testing the static cracking of cubic limestone (size: 200 × 200 × 200 mm) with true triaxial rock mechanics testing machine under the effect of bidirectional stress and by monitoring the evolution process of the cracks generated during the acoustic emission experiment of static cracking, we conclude the following: the experiment results of the acoustic emission show that the cracks start from the lower part of the hole wall until they spread all over the sample. The crack growth rate follows a trend of "from rapidness to slowness." The expansion time is different for the two bunches of cracks. The growth rates can be divided into the rapid increasing period and the rapid declining period, of which the growth rate in declining period is less than that in the increasing period. Also, the growth rate along the vertical direction is greater than that of the horizontal direction. Then the extended model for the static cracking is built according to the theories of elastic mechanics and fracture mechanics. Thus the relation formula between the applied forces of cracks and crack expansion radius is obtained. By comparison with the test results, the model proves to be applicable. In accordance with the actual geological situation of Yangquan No. 3 Mine, the basic parameters of manpower manipulated caving breaking with static crushing are settled, which reaps bumper industrial effects.
A vibro-haptic human-machine interface for structural health monitoring
Mascarenas, David; Plont, Crystal; Brown, Christina; ...
2014-11-01
The structural health monitoring (SHM) community’s goal has been to endow physical systems with a nervous system not unlike those commonly found in living organisms. Typically the SHM community has attempted to do this by instrumenting structures with a variety of sensors, and then applying various signal processing and classification procedures to the data in order to detect the presence of damage, the location of damage, the severity of damage, and to estimate the remaining useful life of the structure. This procedure has had some success, but we are still a long way from achieving the performance of nervous systemsmore » found in biology. This is primarily because contemporary classification algorithms do not have the performance required. In many cases expert judgment is superior to automated classification. This work introduces a new paradigm. We propose interfacing the human nervous system to the distributed sensor network located on the structure and developing new techniques to enable human-machine cooperation. Results from the field of sensory substitution suggest this should be possible. This study investigates a vibro-haptic human-machine interface for SHM. The investigation was performed using a surrogate three-story structure. The structure features three nonlinearity-inducing bumpers to simulate damage. Accelerometers are placed on each floor to measure the response of the structure to a harmonic base excitation. The accelerometer measurements are preprocessed. As a result, the preprocessed data is then encoded encoded as a vibro-tactile stimulus. Human subjects were then subjected to the vibro-tactile stimulus and asked to characterize the damage in the structure.« less
Watanabe, Ryosuke; Katsuhara, Tadasuke; Miyazaki, Hiroshi; Kitagawa, Yuichi; Yasuki, Tsuyoshi
2012-10-01
Injuries in car to pedestrian collisions are affected by various factors such as the vehicle body type, pedestrian body size and impact location as well as the collision speed. This study aimed to investigate the influence of such factors taking a Finite Element (FE) approach. A total of 72 collision cases were simulated using three different vehicle FE models (Sedan, SUV, Mini-Van), three different pedestrian FE models (AM50, AF05, AM95), assuming two different impact locations (center and the corner of the bumper) and at four different collision speeds (20, 30, 40 and 50 km/h). The impact kinematics and the responses of the pedestrian model were validated against those in the literature prior to the simulations. The relationship between the collision speed and the predicted occurrence of head and chest injuries was examined for each case, analyzing the impact kinematics of the pedestrian against the vehicle body and resultant loading to the head and the chest. Strain based indicators were used in the simulation model to estimate skeletal injury (bony fracture) and soft tissue (brain and internal organs) injury. The study results primarily showed that the injury risk became higher with the collision speed, but was also affected by the combination of the factors such as the pedestrian size and the impact location. The study also discussed the injury patterns and trends with respect to the factors examined. In all of the simulated conditions, the model did not predict any severe injury at a collision speed of 20 km/h.
Progress in HTS trapped field magnets: J(sub c), area, and applications
NASA Technical Reports Server (NTRS)
Weinstein, Roy; Ren, Yanru; Liu, Jianxiong; Sawh, Ravi; Parks, Drew; Foster, Charles; Obot, Victor; Arndt, G. Dickey; Crapo, Alan
1995-01-01
Progress in trapped field magnets is reported. Single YBCO grains with diameters of 2 cm are made in production quantities, while 3 cm, 4 1/2 cm and 6 cm diameters are being explored. For single grain tiles: J(sub c) is approximately 10,000 A/cm(exp 2) for melt textured grains; J(sub c) is approximately 40,000 A/cm2 for light ion irradiation; and J(sub c) is approximately 85,000 A/cm(exp 2) for heavy ion irradiation. Using 2 cm diameter tiles bombarded by light ions, we have fabricated a mini-magnet which trapped 2.25 Tesla at 77K, and 5.3 Tesla at 65K. A previous generation of tiles, 1 cm x 1 cm, was used to trap 7.0 Tesla at 55K. Unirradiated 2.0 cm tiles were used to provide 8 magnets for an axial gap generator, in a collaborative experiment with Emerson Electric Co. This generator delivered 100 Watts to a resistive load, at 2265 rpm. In this experiment activation of the TFMs was accomplished by a current pulse of 15 ms duration. Tiles have also been studied for application as a bumper-tether system for the soft docking of spacecraft. A method for optimizing tether forces, and mechanisms of energy dissipation are discussed. A bus bar was constructed by welding three crystals while melt-texturing, such that their a,b planes were parallel and interleaved. The bus bar, an area of approximately 2 cm(exp 2), carried a transport current of 1000 amps, the limit of the testing equipment available.
Progress in HTS Trapped Field Magnets: J(sub c), Area, and Applications
NASA Technical Reports Server (NTRS)
Weinstein, Roy; Ren, Yanru; Liu, Jian-Xiong; Sawh, Ravi; Parks, Drew; Foster, Charles; Obot, Victor; Arndt, G. Dickey; Crapo, Alan
1995-01-01
Progress in trapped field magnets is reported. Single YBCO grains with diameters of 2 cm are made in production quantities, while 3 cm, 4 1/2 cm and 6 cm diameters are being explored. For single grain tiles: J(sub c) - 10,000 A/sq cm for melt textured grains; J(sub c) - 40,000 A/sq cm for light ion irradiation; and J(sub c) - 85,000 A/J(sub c) for heavy ion irradiation. Using 2 cm diameter tiles bombarded by light ions, we have fabricated a mini-magnet which trapped 2.25 Tesla at 77K, and 5.3 Tesla at 65K. A previous generation of tiles, 1 cm x 1 cm, was used to trap 7.0 Tesla at 55K. Unirradiated 2.0 cm tiles were used to provide 8 magnets for an axial gap generator, in a collaborative experiment with Emerson Electric Co. This generator delivered 100 Watts to a resistive load, at 2265 rpm. In this experiment, activation of the TFMs was accomplished by a current pulse of 15 ms duration. Tiles have also been studied for application as a bumper-tether system for the soft docking of spacecraft. A method for optimizing tether forces, and mechanisms of energy dissipation are discussed. A bus bar was constructed by welding three crystals while melt-texturing, such that their a,b planes were parallel and interleaved. The bus bar, of area approx. 2 sq cm, carried a transport current of 1000 amps, the limit of the testing equipment available.
Decisions of Black Parents About Infant Bedding and Sleep Surfaces: A Qualitative Study
Ajao, Taiwo I.; Oden, Rosalind P.; Joyner, Brandi L.
2011-01-01
OBJECTIVE: The goal of this qualitative study was to examine factors influencing decisions by black parents regarding use of soft bedding and sleep surfaces for their infants. METHODS: We conducted focus groups and individual interviews with black mothers of lower and higher socioeconomic status (SES). Mothers were asked about many infant care practices, including sleep surface and bedding. RESULTS: Eighty-three mothers were interviewed, 73 (47 lower and 26 higher SES) in focus groups and 10 (7 lower and 3 higher SES) in individual interviews. The primary reason for using soft surfaces was infant comfort. Parents perceived that infants were uncomfortable if the surface was not soft. Many parents also interpreted “firm sleep surface” to mean taut; they were comfortable with and believed that they were following recommendations for a firm sleep surface when they placed pillows/blankets on the mattress as long as a sheet was pulled tautly over the pillows/blankets. The primary reasons for using soft bedding (including bumper pads) were comfort, safety, and aesthetics. In addition to using bedding to soften sleep surfaces, bedding was used to prevent infant rollover and falls, particularly for infants sleeping on a bed or sofa. Some parents used soft bedding to create an attractive space for the infant. CONCLUSIONS: Many black parents believe that soft bedding will keep their infant safe and comfortable. There is much misunderstanding about the meaning of a “firm” sleep surface. Additional educational messages apparently are needed to change parental perceptions and practices. PMID:21859921
NASA Technical Reports Server (NTRS)
Khatiwada, Suman; Laughman, Jay W.; Armada, Carlos A.; Christiansen, Eric L.; Barrera, Enrique V.
2012-01-01
Advanced composites with multi-functional capabilities are of great interest to the designers of aerospace structures. Polymer matrix composites (PMCs) reinforced with high strength fibers provide a lightweight and high strength alternative to metals and metal alloys conventionally used in aerospace architectures. Novel reinforcements such as nanofillers offer potential to improve the mechanical properties and add multi-functionality such as radiation resistance and sensing capabilities to the PMCs. This paper reports the hypervelocity impact (HVI) test results on ultra-high molecular weight polyethylene (UHMWPE) fiber composites reinforced with single-walled carbon nanotubes (SWCNT) and boron nitride nanotubes (BNNT). Woven UHMWPE fabrics, in addition to providing excellent impact properties and high strength, also offer radiation resistance due to inherent high hydrogen content. SWCNT have exceptional mechanical and electrical properties. BNNT (figure 1) have high neutron cross section and good mechanical properties that add multi-functionality to this system. In this project, epoxy based UHMWPE composites containing SWCNT and BNNT are assessed for their use as bumper shields and as intermediate plates in a Whipple Shield for HVI resistance. Three composite systems are prepared to compare against one another: (I) Epoxy/UHMWPE, (II) Epoxy/UHMWPE/SWCNT and (III) Epoxy/UHMWPE/SWCNT/BNNT. Each composite is a 10.0 by 10.0 by 0.11 cm3 panel, consisting of 4 layers of fabrics arranged in cross-ply orientation. Both SWCNT and BNNT are 0.5 weight % of the fabric preform. Hypervelocity impact tests are performed using a two-stage light gas gun at Rice University
Using the lead vehicle as preview sensor in convoy vehicle active suspension control
NASA Astrophysics Data System (ADS)
Rahman, Mustafizur; Rideout, Geoff
2012-12-01
Both ride quality and roadholding of actively suspended vehicles can be improved by sensing the road ahead of the vehicle and using this information in a preview controller. Previous applications have used look-ahead sensors mounted on the front bumper to measure terrain beneath. Such sensors are vulnerable, potentially confused by water, snow, or other soft obstacles and offer a fixed preview time. For convoy vehicle applications, this paper proposes using the overall response of the preceding vehicle(s) to generate preview controller information for follower vehicles. A robust observer is used to estimate the states of a quarter-car vehicle model, from which road profile is estimated and passed on to the follower vehicle(s) to generate a preview function. The preview-active suspension, implemented in discrete time using a shift register approach to improve simulation time, reduces sprung mass acceleration and dynamic tyre deflection peaks by more than 50% and 40%, respectively. Terrain can change from one vehicle to the next if a loose obstacle is dislodged, or if the vehicle paths are sufficiently different so that one vehicle misses a discrete road event. The resulting spurious preview information can give suspension performance worse than that of a passive or conventional active system. In this paper, each vehicle can effectively estimate the road profile based on its own state trajectory. By comparing its own road estimate with the preview information, preview errors can be detected and suspension control quickly switched from preview to conventional active control to preserve performance improvements compared to passive suspensions.
NASA Astrophysics Data System (ADS)
Ke, Fa-wei; Huang, Jie; Wen, Xue-zhong; Ma, Zhao-xia; Liu, Sen
2016-10-01
In order to study the cracking and intercepting mechanism of stuffed layer configuration on the debris cloud and to develop stuffed layer configuration with better performance, the hypervelocity impact tests on shielding configurations with stuffed layer were carried out. Firstly, the hypervelocity impact tests on the shielding configuration with stuffed layer of 3 layer ceramic fibre and 3 layer aramid fibre were finished, the study results showed that the debris cloud generated by the aluminum sphere impacting bumper at the velocity of about 6.2 km/s would be racked and intercepted by the stuffed layer configuration efficiently when the ceramic fibre layers and aramid fibre layers were jointed together, however, the shielding performance would be declined when the ceramic fibre layers and aramid fibre layers were divided by some distance. The mechanism of stuffed layer racking and intercepting the debris cloud was analyzed according to the above test results. Secondly, based on the mechanism of the stuffed layer cracking and intercepint debirs cloud the hypervelocity impact tests on the following three stuffed layer structures with the equivalent areal density to the 1 mm-thick aluminum plate were also carried out to compare their performance of cracking and intercepting debris cloud. The mechanisms of stuffed layer racking and intercepting the debris cloud were validated by the test result. Thirdly, the influence of the stuffed layer position on the shielding performance was studied by the test, too. The test results would provide reference for the design of better performance shielding configuration with stuffed layer.
Safe Sleep Guideline Adherence in Nationwide Marketing of Infant Cribs and Products.
Kreth, Matthew; Shikany, Tammy; Lenker, Claire; Troxler, R Bradley
2017-01-01
Sudden infant death syndrome and sleep-related sudden unexpected infant death remain leading causes of infant mortality in the United States despite 4 safe sleep guideline restatements over the previous 24 years. Advertising and retail crib displays often promote infant sleep environments that are counter to the most recent American Academy of Pediatrics (AAP) guidelines. Magazine advertisements featuring sleep in parenting magazines from 1992, 2010, and 2015 were reviewed for adherence. Crib displays from nationwide retailers were surveyed for adherence to the latest AAP safe sleep guidelines. The primary outcome was adherence to the guidelines. Of 1758 retail crib displays reviewed, only half adhered to the latest AAP guidelines. The most common reasons for nonadherence were the use of bumper pads and loose bedding. The depiction of infant cribs and sleep products in magazine advertising has become significantly more adherent over time; however, 35% of current advertisements depict nonadherent, unsafe sleep environments. Magazine advertising portraying safe sleep environments revealed racial and ethnic disparities. Although improvements have been made over time with increased adherence to AAP safe sleep guidelines, significant deficiencies remain. Advertising continues to depict unsafe sleep environments. Crib manufacturers and retail establishments continue to market and sell bedding and sleep products considered unsafe by the AAP in approximately half of retail crib displays. Pediatric and public health care providers should continue educational and advocacy efforts aimed at the public, but should also include retailers, manufacturers, and advertising professionals to foster improved sleep environments for all children. Copyright © 2017 by the American Academy of Pediatrics.
Martyna, Agnieszka; Zadora, Grzegorz; Neocleous, Tereza; Michalska, Aleksandra; Dean, Nema
2016-08-10
Many chemometric tools are invaluable and have proven effective in data mining and substantial dimensionality reduction of highly multivariate data. This becomes vital for interpreting various physicochemical data due to rapid development of advanced analytical techniques, delivering much information in a single measurement run. This concerns especially spectra, which are frequently used as the subject of comparative analysis in e.g. forensic sciences. In the presented study the microtraces collected from the scenarios of hit-and-run accidents were analysed. Plastic containers and automotive plastics (e.g. bumpers, headlamp lenses) were subjected to Fourier transform infrared spectrometry and car paints were analysed using Raman spectroscopy. In the forensic context analytical results must be interpreted and reported according to the standards of the interpretation schemes acknowledged in forensic sciences using the likelihood ratio approach. However, for proper construction of LR models for highly multivariate data, such as spectra, chemometric tools must be employed for substantial data compression. Conversion from classical feature representation to distance representation was proposed for revealing hidden data peculiarities and linear discriminant analysis was further applied for minimising the within-sample variability while maximising the between-sample variability. Both techniques enabled substantial reduction of data dimensionality. Univariate and multivariate likelihood ratio models were proposed for such data. It was shown that the combination of chemometric tools and the likelihood ratio approach is capable of solving the comparison problem of highly multivariate and correlated data after proper extraction of the most relevant features and variance information hidden in the data structure. Copyright © 2016 Elsevier B.V. All rights reserved.
Health education: historic windows of opportunity.
Grant, J P
1992-01-01
In 1991, the Executive Director of UNICEF addressed the World Conference on Health Education in Helsinki, Finland which centered on international cooperation in improving health. Health educators should convince world leaders to apply the money available after reductions in military spending due to the end of the Cold War toward revitalizing health and education systems and alleviating poverty. Another opportunity that they should not let slip away is that more countries are choosing democracy. The international consensus is now leaning toward human centered development. At least 71 national leaders and representatives from 88 other countries have supported the World Summit Plan of Action which emphasizes health education efforts leading toward child survival. This global, political endorsement also presents a plan for social mobilization. Health educators have already contributed greatly to the success of achieving universal child immunization (80%) by the end of 1990. They communicated health education messages via the mass media and traditional channels to motivate individuals and society to immunize their children. UNICEF has 27 goals for the 1990s such as eradication of polio and guinea worm disease. In 1989, UNICEF, WHO, UNESCO, and about 100 other agencies began the Facts for Life initiative by 1st publishing a book. Lay and professional health educators have incorporated its messages into various media: street theater, radio, comics, soap operas, billboards, T-shirts, and bumper stickers. Medical research has shown that individual responsibility for one's own health adds years to life expectancy, e.g., individuals should not smoke. Health educators face the challenge of reaching adolescents, especially since most behavior patterns are established during adolescence. Other challenges include developing effective messages to curb the AIDS pandemic, to motivate hospitals to promote breast feeding, and to encourage world leaders to place children's needs at the top of society's priorities.
The regulatory contract and restructuring: A modest proposal
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hartman, R.S.; Tabors, R.
1996-12-01
History does not support the notion that the regulatory contract has treated utilities unfairly. But to the extent it is decided, for other reasons, that utilities should receive transition payments as the industry is pushed to a more competitive framework, there are four important principles to keep firmly in mind. To paraphrase the contemporary bumper sticker, `in the economic, social and/or romantic affairs of man and/or woman, unexpected events happen.` A more thoughtful interpretation of this notion would be that in economic and social interrelationships, individuals formulate behavioral plans based upon expectations about the state of the world and/or themore » behavior of other individuals. Should those expectations turn out to be incorrect, the individuals relying upon those expectations and their plans will be frustrated. The frustrated individuals may rail against their fate; they may accept their disappointment stoically. They may `take arms against a sea of troubles, and by opposing end them.` Alternatively and more likely in late twentieth century America, they may litigate (or threaten litigation) for breach of contract, claiming that some implicit or explicit, oral or written contract has been breached and that reliance upon that contract has consequently damaged them. The discussion of assets potentially stranded by the ongoing restructuring of the U.S. electric power industry has been characterized by the latter response. As some utilities have faced the possible economic obsolescence of particular generation assets in light of technological changes and altered regulatory rules, they have invoked the notion of a `regulatory contract` having governed their expectations, behavior and past capital investment. By implication, these utilities argue that they should be fully compensated for all cost incurred under good faith adherence to past regulatory processes and procedures.« less
Meteoroid and Orbital Debris Threats to NASA's Docking Seals: Initial Assessment and Methodology
NASA Technical Reports Server (NTRS)
deGroh, Henry C., III; Nahra, Henry K.
2009-01-01
The Crew Exploration Vehicle (CEV) will be exposed to the Micrometeoroid Orbital Debris (MMOD) environment in Low Earth Orbit (LEO) during missions to the International Space Station (ISS) and to the micrometeoroid environment during lunar missions. The CEV will be equipped with a docking system which enables it to connect to ISS and the lunar module known as Altair; this docking system includes a hatch that opens so crew and supplies can pass between the spacecrafts. This docking system is known as the Low Impact Docking System (LIDS) and uses a silicone rubber seal to seal in cabin air. The rubber seal on LIDS presses against a metal flange on ISS (or Altair). All of these mating surfaces are exposed to the space environment prior to docking. The effects of atomic oxygen, ultraviolet and ionizing radiation, and MMOD have been estimated using ground based facilities. This work presents an initial methodology to predict meteoroid and orbital debris threats to candidate docking seals being considered for LIDS. The methodology integrates the results of ground based hypervelocity impacts on silicone rubber seals and aluminum sheets, risk assessments of the MMOD environment for a variety of mission scenarios, and candidate failure criteria. The experimental effort that addressed the effects of projectile incidence angle, speed, mass, and density, relations between projectile size and resulting crater size, and relations between crater size and the leak rate of candidate seals has culminated in a definition of the seal/flange failure criteria. The risk assessment performed with the BUMPER code used the failure criteria to determine the probability of failure of the seal/flange system and compared the risk to the allotted risk dictated by NASA's program requirements.
An Agent-Based Interface to Terrestrial Ecological Forecasting
NASA Technical Reports Server (NTRS)
Golden, Keith; Nemani, Ramakrishna; Pang, Wanlin; Votava, Petr
2005-01-01
The latest generation of NASA Earth Observing System (EOS) satellites has brought a new dimension to continuous monitoring of the living part of the Earth System, the biosphere. EOS data can now provide weekly global measures of vegetation productivity and ocean chlorophyll, and many related biophysical factors such as land cover changes or snowmelt rates. However, the highest economic value would come from forecasting impending conditions of the biosphere, to allow decision makers to mitigate dangers or exploit positive trends. NASA's strategic plan for the Earth Science Enterprise i d e n a s ecological forecasting as a focus for research. Ecological forecasting predicts the effects of changes in the physical, chemical and biological environment on ecosystem activity. Possible applications of such a system include predicting shortfalls or bumper crops of agricultural production, populations of threatened or invasive species or wildfire danger in time to allow improves preparation and logistical efficiency. Petabytes of remote sensing data are now available to help measure, understand and forecast changes in the Earth system, but using these data effectively can be surprisingly hard. The volume and variety of data files and formats are daunting. Simple data management activities, such as locating and transferring files, changing file formats, gridding point data, and scaling and reprojecting gridded data, can consume far more personnel time and resources than the actual data analysis. Some scientists commit to a particular data source or resolution just because using anything different would be more effort that it's worth. Better tools can help, but most of the tools developed to date are little more than shell scripts; they lack the flexibility to meet the diverse needs of users and are difficult to extend to handle changes in available data sources.
Self-Supervised Learning of Terrain Traversability from Proprioceptive Sensors
NASA Technical Reports Server (NTRS)
Bajracharya, Max; Howard, Andrew B.; Matthies, Larry H.
2009-01-01
Robust and reliable autonomous navigation in unstructured, off-road terrain is a critical element in making unmanned ground vehicles a reality. Existing approaches tend to rely on evaluating the traversability of terrain based on fixed parameters obtained via testing in specific environments. This results in a system that handles the terrain well that it trained in, but is unable to process terrain outside its test parameters. An adaptive system does not take the place of training, but supplements it. Whereas training imprints certain environments, an adaptive system would imprint terrain elements and the interactions amongst them, and allow the vehicle to build a map of local elements using proprioceptive sensors. Such sensors can include velocity, wheel slippage, bumper hits, and accelerometers. Data obtained by the sensors can be compared to observations from ranging sensors such as cameras and LADAR (laser detection and ranging) in order to adapt to any kind of terrain. In this way, it could sample its surroundings not only to create a map of clear space, but also of what kind of space it is and its composition. By having a set of building blocks consisting of terrain features, a vehicle can adapt to terrain that it has never seen before, and thus be robust to a changing environment. New observations could be added to its library, enabling it to infer terrain types that it wasn't trained on. This would be very useful in alien environments, where many of the physical features are known, but some are not. For example, a seemingly flat, hard plain could actually be soft sand, and the vehicle would sense the sand and avoid it automatically.
Optimized Trajectories to the Nearest Stars Using Lightweight High-velocity Photon Sails
NASA Astrophysics Data System (ADS)
Heller, René; Hippke, Michael; Kervella, Pierre
2017-09-01
New means of interstellar travel are now being considered by various research teams, assuming lightweight spaceships to be accelerated via either laser or solar radiation to a significant fraction of the speed of light (c). We recently showed that gravitational assists can be combined with the stellar photon pressure to decelerate an incoming lightsail from Earth and fling it around a star or bring it to rest. Here, we demonstrate that photogravitational assists are more effective when the star is used as a bumper (I.e., the sail passes “in front of” the star) rather than as a catapult (I.e., the sail passes “behind” or “around” the star). This increases the maximum deceleration at α Cen A and B and reduces the travel time of a nominal graphene-class sail (mass-to-surface ratio 8.6× {10}-4 {{g}} {{{m}}}-2) from 95 to 75 years. The maximum possible velocity reduction upon arrival depends on the required deflection angle from α Cen A to B and therefore on the binary’s orbital phase. Here, we calculate the variation of the minimum travel times from Earth into a bound orbit around Proxima for the next 300 years and then extend our calculations to roughly 22,000 stars within about 300 lt-yr. Although α Cen is the most nearby star system, we find that Sirius A offers the shortest possible travel times into a bound orbit: 69 years assuming 12.5% c can be obtained at departure from the solar system. Sirius A thus offers the opportunity of flyby exploration plus deceleration into a bound orbit of the companion white dwarf after relatively short times of interstellar travel.
Meteoroid and Orbital Debris Threats to NASA's Docking Seals: Initial Assessment and Methodology
NASA Technical Reports Server (NTRS)
deGroh, Henry C., III; Gallo, Christopher A.; Nahra, Henry K.
2009-01-01
The Crew Exploration Vehicle (CEV) will be exposed to the Micrometeoroid Orbital Debris (MMOD) environment in Low Earth Orbit (LEO) during missions to the International Space Station (ISS) and to the micrometeoroid environment during lunar missions. The CEV will be equipped with a docking system which enables it to connect to ISS and the lunar module known as Altair; this docking system includes a hatch that opens so crew and supplies can pass between the spacecrafts. This docking system is known as the Low Impact Docking System (LIDS) and uses a silicone rubber seal to seal in cabin air. The rubber seal on LIDS presses against a metal flange on ISS (or Altair). All of these mating surfaces are exposed to the space environment prior to docking. The effects of atomic oxygen, ultraviolet and ionizing radiation, and MMOD have been estimated using ground based facilities. This work presents an initial methodology to predict meteoroid and orbital debris threats to candidate docking seals being considered for LIDS. The methodology integrates the results of ground based hypervelocity impacts on silicone rubber seals and aluminum sheets, risk assessments of the MMOD environment for a variety of mission scenarios, and candidate failure criteria. The experimental effort that addressed the effects of projectile incidence angle, speed, mass, and density, relations between projectile size and resulting crater size, and relations between crater size and the leak rate of candidate seals has culminated in a definition of the seal/flange failure criteria. The risk assessment performed with the BUMPER code used the failure criteria to determine the probability of failure of the seal/flange system and compared the risk to the allotted risk dictated by NASA s program requirements.
Drivers of U.S. mineral demand
Sznopek, John L.
2006-01-01
Introduction: The word 'demand' has different meanings for different people. To some, it means their 'wants and needs,' to others it is what they consume. Yet, when considering economics, demand refers to the specific amounts of goods or services that individuals will purchase at various prices. Demand is measured over a given time period. It is determined by a number of factors including income, tastes, and the price of complementary and substitute goods. In this paper, the term consumption is used fairly synonymously with the term demand. Most mineral commodities, like iron ore, copper, zinc, and gravel, are intermediate goods, which means that they are used in the production of other goods, called final goods. Demand for intermediate goods is called derived demand because such demand is derived from the demand for final goods. When demand increases for a commodity, generally the price rises. With everything else held constant, this increases the profits for those who provide this commodity. Normally, this would increase profits of existing producers and attract new producers to the market. When demand for a commodity decreases, generally the price falls. Normally, this would cause profits to fall and, as a consequence, the least efficient firms may be forced from the industry. Demand changes for specific materials as final goods or production techniques are reengineered while maintaining or improving product performance, for example, the use of aluminum in the place of copper in long distance electrical transmission lines or plastic replacing steel in automobile bumpers. Substitution contributes to efficient material usage by utilizing cheaper or technically superior materials. In this way, it may also alleviate materials scarcity. If a material becomes relatively scarce (and thus more expensive), a more abundant (and less expensive) material generally replaces it (Wagner and others, 2003, p. 91).
NASA Astrophysics Data System (ADS)
Humber, M. L.; Becker-Reshef, I.; Nordling, J.; Barker, B.; McGaughey, K.
2014-12-01
The GEOGLAM Crop Monitor's Crop Assessment Tool was released in August 2013 in support of the GEOGLAM Crop Monitor's objective to develop transparent, timely crop condition assessments in primary agricultural production areas, highlighting potential hotspots of stress/bumper crops. The Crop Assessment Tool allows users to view satellite derived products, best available crop masks, and crop calendars (created in collaboration with GEOGLAM Crop Monitor partners), then in turn submit crop assessment entries detailing the crop's condition, drivers, impacts, trends, and other information. Although the Crop Assessment Tool was originally intended to collect data on major crop production at the global scale, the types of data collected are also relevant to the food security and rangelands monitoring communities. In line with the GEOGLAM Countries at Risk philosophy of "foster[ing] the coordination of product delivery and capacity building efforts for national and regional organizations, and the development of harmonized methods and tools", a modified version of the Crop Assessment Tool is being developed for the USAID Famine Early Warning Systems Network (FEWS NET). As a member of the Countries at Risk component of GEOGLAM, FEWS NET provides agricultural monitoring, timely food security assessments, and early warnings of potential significant food shortages focusing specifically on countries at risk of food security emergencies. While the FEWS NET adaptation of the Crop Assessment Tool focuses on crop production in the context of food security rather than large scale production, the data collected is nearly identical to the data collected by the Crop Monitor. If combined, the countries monitored by FEWS NET and GEOGLAM Crop Monitor would encompass over 90 countries representing the most important regions for crop production and food security.
Nyström, Max; Machytka, Evzen; Norén, Erik; Testoni, Pier Alberto; Janssen, Ignace; Turró Homedes, Jesus; Espinos Perez, Jorge Carlos; Turro Arau, Roman
2018-02-01
The objective of this post-market study was to evaluate long-term safety and efficacy of aspiration therapy (AT) in a clinical setting in five European clinics. The AspireAssist® System (Aspire Bariatrics, Inc. King of Prussia, PA) is an endoscopic weight loss therapy utilizing a customized percutaneous endoscopic gastrostomy tube and an external device to aspirate approximately 30% of ingested calories after a meal, in conjunction with lifestyle counseling. A total of 201 participants, with body mass index (BMI) of 35.0-70.0 kg/m 2 , were enrolled in this study from June 2012 to December 2016. Mean baseline BMI was 43.6 ± 7.2 kg/m 2 . Mean percent total weight loss at 1, 2, 3, and 4 years, respectively, was 18.2% ± 9.4% (n/N = 155/173), 19.8% ± 11.3% (n/N = 82/114), 21.3% ± 9.6% (n/N = 24/43), and 19.2% ± 13.1% (n/N = 12/30), where n is the number of measured participants and N is the number of participants in the absence of withdrawals or lost to follow-up. Clinically significant reductions in glycated hemoglobin (HbA1C), triglycerides, and blood pressure were observed. For participants with diabetes, HbA1C decreased by 1% (P < 0.0001) from 7.8% at baseline to 6.8% at 1 year. The only serious complications were buried bumpers, experienced by seven participants and resolved by removal/replacement of the A-Tube, and a single case of peritonitis, resolved with a 2-day course of intravenous antibiotics. This study establishes that aspiration therapy is a safe, effective, and durable weight loss therapy in people with classes II and III obesity in a clinical setting. ISRCTN 49958132.
Grassia, Vincenzo; d'Apuzzo, Fabrizia; Jamilian, Abdolreza; Femiano, Felice; Favero, Lorenzo; Perillo, Letizia
2015-01-01
Aim of this retrospective observational study was to compare upper and lower dental changes in patients treated with Rapid Maxillary Expansion (RME) and Mixed Maxillary Expansion (MME), assessed by dental cast analysis. Treatment groups consisted of 42 patients: the RME group (n = 21) consisted of 13 female and 8 male subjects with the mean age of 8.8 years ± 1.37 at T0 and 9.6 years ± 1.45 at T1; the MME group (n = 21) consisted of 12 female and 9 male patients with a mean age of 8.9 years ± 2.34 at T0 and 10.5 years ± 2.08 at T1. The upper and lower arch analysis was performed on four dental bilateral landmarks, on upper and lower casts; also upper and lower arch depths were measured. The groups were compared using independent sample t-test to estimate dental changes in upper and lower arches. Before expansion treatment (T0), the groups were similar for all examined variables (p>0.05). In both RME and MME group, significant increments in all the variables for maxillary and mandibular arch widths were observed after treatment. No significant differences in maxillary and mandibular arch depths were observed at the end of treatment in both groups. An evaluation of the changes after RME and MME (T1) showed statistically significant differences in mandibular arch depth (p<0.001) and maxillary intercanine widths (p<0.05). Differences in maxillary arch depth and arch width measurements were not significant. RME and MME can be considered two effective treatment options to improve transverse arch dimensions and gain space in the dental arches. A greater lower arch expansion was observed in the MME group, which might be attributed to the "lip bumper effects" observed in the MME protocol.
Are Weeds Hitchhiking a Ride on Your Car? A Systematic Review of Seed Dispersal on Cars
Ansong, Michael; Pickering, Catherine
2013-01-01
When traveling in cars, we can unintentionally carry and disperse weed seed; but which species, and where are they a problem? To answer these questions, we systematically searched the scientific literature to identify all original research studies that assess seed transported by cars and listed the species with seed on/in cars. From the 13 studies that fit these criteria, we found 626 species from 75 families that have seed that can be dispersed by cars. Of these, 599 are listed as weeds in some part of the world, with 439 listed as invasive or naturalized alien species in one or more European countries, 248 are invasive/noxious weeds in North America, 370 are naturalized alien species in Australia, 167 are alien species in India, 77 are invasive species in China and 23 are declared weeds/invaders in South Africa. One hundred and one are classified as internationally important environmental weeds. Although most (487) were only recorded once, some species such as Chenopodium album, Poa pratensis and Trifolium repens were common among studies. Perennial graminoids seem to be favoured over annual graminoids while annual forbs are favoured over perennial forbs. Species characteristics including seed size and morphology and where the plants grew affected the probability that their seed was transported by cars. Seeds can be found in many different places on cars including under the chassis, front and rear bumpers, wheel wells and rims, front and back mudguards, wheel arches, tyres and on interior floor mats. With increasing numbers of cars and expanding road networks in many regions, these results highlight the importance of cars as a dispersal mechanism, and how it may favour invasions by some species over others. Strategies to reduce the risk of seed dispersal by cars include reducing seed on cars by mowing road verges and cleaning cars. PMID:24265803
Forward Collision Warning: Clues to Optimal Timing of Advisory Warnings
Aksan, Nazan; Sager, Lauren; Hacker, Sarah; Marini, Robert; Dawson, Jeffrey; Anderson, Steven; Rizzo, Matthew
2016-01-01
We examined the effectiveness of a heads-up Forward Collision Warning (FCW) system in 39 younger to middle aged drivers (25-50, mean = 35 years) and 37 older drivers (66-87, mean = 77 years). The warnings were implemented in a fixed based, immersive, 180 degree forward field of view simulator. The FCW included a visual advisory component consisting of a red horizontal bar which flashed in the center screen of the simulator that was triggered at time-to-collision (TTC) 4 seconds. The bar roughly overlapped the rear bumper of the lead vehicle, just below the driver's line-of-sight. A sustained auditory tone (~80 dB) was activated at TTC=2 to alert the driver to an imminent collision. Hence, the warning system differed from the industry standard in significant ways. 95% Confidence intervals for the safety gains ranged from −.03 to .19 seconds in terms of average correction time across several activations. Older and younger adults did not differ in terms of safety gains. Closer inspection of data revealed that younger to middle aged drivers were already braking (42%) on a larger proportion of FCW activations than older drivers (26%), p < .001. Conversely, older drivers were still accelerating (38%) on a larger proportion of FCW activations than younger to middle aged drivers (23%) at the time FCW was activated, p < .009. There were no differences in the proportion of activations when drivers were coasting at the time FCW was activated, p = .240. Furthermore, large individual differences in basic visual, motor, and cognitive function predicted the tendency to brake prior to FCW activation. Those who tended to be better functioning in each of these domains were more likely to be already braking prior to FCW activation at the fixed threshold of TTC=4. These findings suggest optimal timing for advisory alerts for forward events may need to be larger than TTC=4. PMID:27648455
AN ANALYSIS OF THE IMPACT OF SPORTS UTILITY VEHICLES IN THE UNITED STATES
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, S.C.
During the 1990s, sport utility vehicles (SUVs) became the fastest growing segment of the auto industry, especially those in the medium-size category. In 1999, SUV sales reached almost 19% of the total light vehicle market and the mix of SUVs on the road, as measured by registration data, was about 8.7%. This immense popularity has been called by some a passing fad--vehicle purchases based on the SUV ''image''. But the continued yearly increases in SUV sales seem to indicate a more permanent trend. Additional explanations for SUV popularity include the general economic well being in the United States, a perceptionmore » of safety, and ''utility''. Generally larger and heavier than the typical automobile, SUVs require more fuel per mile to operate and produce greater amounts of pollutants. They are also driven further annually than are automobiles of the same vintage, a fact that exacerbates the fuel-use and emission problems. Although buyers believe that SUVs are safer than automobiles which they are in some cases, SUVs are more prone to roll-overs than are automobiles. In addition, SUVs, with their higher bumpers and greater weight, may be a threat to other vehicles on the highway, especially in side-impact crashes. With sales projected to grow to over 3 million units per year beginning in 2001, SUVs show no sign of decreasing in popularity. These vehicles are used primarily for general mobility, rather than off-road activities. An emphasis on better fuel economy and improved emissions control could address environmental and oil dependency concerns. In fact, recently, two vehicle manufacturers announced intentions of improving the fuel economy of their SUVs in the next few years. Also, tests simulating crashes involving automobiles and SUVs could provide valuable data for identifying potential safety design issues. It is clear that automobiles and SUVs will be sharing the highways for years to come.« less
[Whiplash injury of the neck from concepts to facts].
Revel, M
2003-04-01
To focus on a topic of traumatology and rehabilitation becoming recently a much debated public health problem. A references search from Medline database with whiplash as keyword was carried out. Were selected articles with abstracts in french or english and focusing on accidentology, biomechanics, demonstrated lesions, epidemiology and treatments. From 1664 references found, 232 were reviewed. The usual mechanism of crash is a rear-end collision inducing in the occupants of the bumped vehicle a sudden lower cervical spine extension with upper flexion followed by a global flexion. In nearly 50% of the cases, the stress occurring in the collision is comparable to that observed in bumper cars. The velocity changes are seldom up to 15 km/h. A headrest at the level of the center of gravity of the head restrict significantly the extension of the neck. Every structure of the cervical spine could be damaged and mainly the facet joints but the lesions were only demonstrated in severes traumatisms. The discrepancies in incidence among the different countries could be related to their medicolegal system. Although subjectives, the early symptoms are rather similar among patients suggesting true anatomical or functional disorders but the chronicity seems to be mainly related to social and psychological factors. The association of: no posterior midline cervical tenderness, no intoxication, normal alertness, no focal neurological deficit and no painful distracting injuries has a good predictive value of the lack of osteo-articular lesion on X-rays. Except the grade IV of the Quebec task Force (0, no symptom; 1, pain and stiffness; 2, neck complaint and physical signs; 3, neck complaint and neurological signs; 4, fracture or dislocation) the use of a collar should be avoided and the cervical spine should be mobilized. In most whiplash injuries, the mildness should be early stated, mobilization encouraged, and procedures of compensation shortened.
Wenzel, Tom
2013-07-01
The National Highway Traffic Safety Administration (NHTSA) recently updated its 2003 and 2010 logistic regression analyses of the effect of a reduction in light-duty vehicle mass on US fatality risk per vehicle mile traveled (VMT). The current NHTSA analysis is the most thorough investigation of this issue to date. LBNL's assessment of the analysis indicates that the estimated effect of mass reduction on risk is smaller than in the previous studies, and statistically non-significant for all but the lightest cars. The effects three recent trends in vehicle designs and technologies have on societal fatality risk per VMT are estimated, and whether these changes might affect the relationship between vehicle mass and fatality risk in the future. Side airbags are found to reduce fatality risk in cars, but not necessarily light trucks or CUVs/minivans, struck in the side by another light-duty vehicle; reducing the number of fatalities in cars struck in the side is predicted to reduce the estimated detrimental effect of footprint reduction, but increase the detrimental effect of mass reduction, in cars on societal fatality risk. Better alignment of light truck bumpers with those of other vehicles appears to result in a statistically significant reduction in risk imposed on car occupants; however, reducing this type of fatality will likely have little impact on the estimated effect of mass or footprint reduction on risk. Finally, shifting light truck drivers into safer, car-based vehicles, such as sedans, CUVs, and minivans, would result in larger reductions in societal fatalities than expected from even substantial reductions in the masses of light trucks. A strategy of shifting drivers from truck-based to car-based vehicles would reduce fuel use and greenhouse gas emissions, while improving societal safety. Copyright © 2013 Elsevier Ltd. All rights reserved.
Are weeds hitchhiking a ride on your car? A systematic review of seed dispersal on cars.
Ansong, Michael; Pickering, Catherine
2013-01-01
When traveling in cars, we can unintentionally carry and disperse weed seed; but which species, and where are they a problem? To answer these questions, we systematically searched the scientific literature to identify all original research studies that assess seed transported by cars and listed the species with seed on/in cars. From the 13 studies that fit these criteria, we found 626 species from 75 families that have seed that can be dispersed by cars. Of these, 599 are listed as weeds in some part of the world, with 439 listed as invasive or naturalized alien species in one or more European countries, 248 are invasive/noxious weeds in North America, 370 are naturalized alien species in Australia, 167 are alien species in India, 77 are invasive species in China and 23 are declared weeds/invaders in South Africa. One hundred and one are classified as internationally important environmental weeds. Although most (487) were only recorded once, some species such as Chenopodium album, Poa pratensis and Trifolium repens were common among studies. Perennial graminoids seem to be favoured over annual graminoids while annual forbs are favoured over perennial forbs. Species characteristics including seed size and morphology and where the plants grew affected the probability that their seed was transported by cars. Seeds can be found in many different places on cars including under the chassis, front and rear bumpers, wheel wells and rims, front and back mudguards, wheel arches, tyres and on interior floor mats. With increasing numbers of cars and expanding road networks in many regions, these results highlight the importance of cars as a dispersal mechanism, and how it may favour invasions by some species over others. Strategies to reduce the risk of seed dispersal by cars include reducing seed on cars by mowing road verges and cleaning cars.
Secondary Impacts on Structures on the Lunar Surface
NASA Technical Reports Server (NTRS)
Christiansen, Eric; Walker, James D.; Grosch, Donald J.
2010-01-01
The Altair Lunar Lander is being designed for the planned return to the Moon by 2020. Since it is hoped that lander components will be re-used by later missions, studies are underway to examine the exposure threat to the lander sitting on the Lunar surface for extended periods. These threats involve both direct strikes of meteoroids on the vehicle as well as strikes from Lunar regolith and rock thrown by nearby meteorite strikes. Currently, the lander design is comprised of up to 10 different types of pressure vessels. These vessels included the manned habitation module, fuel, cryogenic fuel and gas storage containers, and instrument bays. These pressure vessels have various wall designs, including various aluminum alloys, honeycomb, and carbon-fiber composite materials. For some of the vessels, shielding is being considered. This program involved the test and analysis of six pressure vessel designs, one of which included a Whipple bumper shield. In addition to the pressure vessel walls, all the pressure vessels are wrapped in multi-layer insulation (MLI). Two variants were tested without the MLI to better understand the role of the MLI in the impact performance. The tests of performed were to examine the secondary impacts on these structures as they rested on the Lunar surface. If a hypervelocity meteor were to strike the surface nearby, it would throw regolith and rock debris into the structure at a much lower velocity. Also, when the manned module departs for the return to Earth, its rocket engines throw up debris that can impact the remaining lander components and cause damage. Glass spheres were used as a stimulant for the regolith material. Impact tests were performed with a gas gun to find the V50 of various sized spheres striking the pressure vessels. The impacts were then modeled and a fast-running approximate model for the V50 data was developed. This model was for performing risk analysis to assist in the vessel design and in the identification of ideal long-term mission sites. This paper reviews the impact tests and analysis and modeling examining the impact threat to various components in the lander design.
Nicholson, J D W; Nicholson, K L; Frenzel, L L; Maddock, R J; Delmore, R J; Lawrence, T E; Henning, W R; Pringle, T D; Johnson, D D; Paschal, J C; Gill, R J; Cleere, J J; Carpenter, B B; Machen, R V; Banta, J P; Hale, D S; Griffin, D B; Savell, J W
2013-10-01
This survey consisted of data collected from 23 beef harvest plants to document transportation procedures, management practices, and health assessments of market beef and dairy cows and bulls (about n ≅ 7,000 animals). Gooseneck/bumper-pulled trailers were used more often to transport dairy cattle than beef cattle to market whereas tractor-trailers were used more often to transport beef cattle than dairy cattle. All loads (n = 103) met the American Meat Institute Foundation guidelines for spacing. Loads where more than 3% of the cattle slipped during unloading were observed in 27.3% of beef loads and 29.0% of the dairy loads. Beef loads had numerically greater usage of electrical prods (32.4%) versus dairy loads (15.4%) during unloading and were more likely to have a variety of driving aids used more aggressively on them. Fewer cattle had horns, brands, and mud/manure contamination on hides than in the previous survey in 1999. The predominant hide color for beef cows was black (44.2%) whereas the predominant color for dairy cows was the Holstein pattern (92.9%). Fewer cattle displayed evidence of bovine ocular neoplasia (2.9%) than in previous surveys in 1994 (8.5%) and 1999 (4.3%). Knots on live cattle were found less in the round (0.5%) and more in the shoulder region (4.6%) than in 1999 (1.4% and 0.4%, respectively). Dairy cows were more frequently lame in 2007 (48.7%) than 1999 (39.2%) whereas beef cows had numerically less lameness (16.3% vs. 26.6%, respectively). Most beef cows (62.3%) and dairy cows (68.9%) received midpoint body condition scores (3, 4, and 5 for beef; 2 and 3 for dairy). Beef cows had higher numerical percentages of no defects present (72.0%) versus dairy cows (63.0%) when evaluated for a variety of reproductive, health, or management conditions. Continued improvements in several key factors related to transportation, management, and health were observed in this survey, which could result in increased value in market beef and dairy cows and bulls.
Single endoscopist-performed percutaneous endoscopic gastrostomy tube placement.
Erdogan, Askin
2013-07-14
To investigate whether single endoscopist-performed percutaneous endoscopic gastrostomy (PEG) is safe and to compare the complications of PEG with those reported in the literature. Patients who underwent PEG placement between June 2001 and August 2011 at the Baskent University Alanya Teaching and Research Center were evaluated retrospectively. Patients whose PEG was placed for the first time by a single endoscopist were enrolled in the study. PEG was performed using the pull method. All of the patients were evaluated for their indications for PEG, major and minor complications resulting from PEG, nutritional status, C-reactive protein (CRP) levels and the use of antibiotic treatment or antibiotic prophylaxis prior to PEG. Comorbidities, rates, time and reasons for mortality were also evaluated. The reasons for PEG removal and PEG duration were also investigated. Sixty-two patients underwent the PEG procedure for the first time during this study. Eight patients who underwent PEG placement by 2 endoscopists were not enrolled in the study. A total of 54 patients were investigated. The patients' mean age was 69.9 years. The most common indication for PEG was cerebral infarct, which occurred in approximately two-thirds of the patients. The mean albumin level was 3.04 ± 0.7 g/dL, and 76.2% of the patients' albumin levels were below the normal values. The mean CRP level was high in 90.6% of patients prior to the procedure. Approximately two-thirds of the patients received antibiotics for either prophylaxis or treatment for infections prior to the PEG procedure. Mortality was not related to the procedure in any of the patients. Buried bumper syndrome was the only major complication, and it occurred in the third year. In such case, the PEG was removed and a new PEG tube was placed via surgery. Eight patients (15.1%) experienced minor complications, 6 (11.1%) of which were wound infections. All wound infections except one recovered with antibiotic treatment. Two patients had bleeding from the PEG site, one was resolved with primary suturing and the other with fresh frozen plasma transfusion. The incidence of major and minor complications is in keeping with literature. This finding may be noteworthy, especially in developing countries.
NASA Astrophysics Data System (ADS)
Economou, T. E.; Tuzzolino, A. J.; Green, S. F.
On January 2nd, 2004, the Stardust spacecraft successfully encountered the Wild 2 comet. The Dust Flux Monitor Instrument (DFMI) provided quantitative measurements of dust particle fluxes and particle mass distribution throughout the entire flythrough. The DFMI consists of two different dust detector systems --- a polyvinylidene fluoride (PVDF) dust sensor unit (SU), which measures particles in the 10-11 to 10-4 mass, and a dual acoustic sensor system (DASS), which utilizes two piezoelectric accelerometers mounted on the first two layers of the spacecraft Whipple dust shield to measure the flux ofparticles with mass larger than 10-4 g. The DFMI on the stardust mission was designed, built and tested at the University of Chicago. The Open University provided the calibration and will perform the analysis of the data from the acoustic sensors. The DFMI instrument was turned on 15 minutes before the estimated closest approach. It started to detect the first dust particles just a few minutes before the closest approach with both types of the sensors in the instrument. As the S/C was departing the comet several more dust particle streams were encountered some 2-12 minutes after the closest approach. The time distribution of dust particles detected by DFMI is not uniform and they seem to come in closely spaced swarms of particles separated by many seconds with no events. The source of these particles is believed to be several of the jet streams that were observed in many of the images obtained by the navigation camera on the STARDUST spacecraft. Data flux rates and dust particle mass distribution are currently being evaluated and will be presented at the meeting. The instrument detected thousands of small particles and a few of them were large enough to even penetrate the first layer of the Whipple bumper shield. From the DFMI data it has been estimated that more than several thousands particles larger than 20 μ in diameter have been collected in the aerogel collector that will returned back to Earth in January 2006.
Petit, Philippe; Trosseille, Xavier; Dufaure, Nicolas; Dubois, Denis; Potier, Pascal; Vallancien, Guy
2014-11-01
In the ECE 127 Regulation on pedestrian leg protection, as well as in the Euro NCAP test protocol, a legform impactor hits the vehicle at the speed of 40 kph. In these tests, the knee is fully extended and the leg is not coupled to the upper body. However, the typical configuration of a pedestrian impact differs since the knee is flexed during most of the gait cycle and the hip joint applies an unknown force to the femur. This study aimed at investigating the influence of the inertia of the upper body (modelled using an upper body mass fixed at the proximal end of the femur) and the initial knee flexion angle on the lower limb injury outcome. In total, 18 tests were conducted on 18 legs from 9 Post Mortem Human Subjects (PMHS). The principle of these tests was to impact the leg at 40 kph using a sled equipped with 3 crushing steel tubes, the stiffness of which were representative of the front face of a European sedan (bonnet leading edge, bumper and spoiler). The mass of the equipped sled was 74.5 kg. The test matrix was designed to perform 4 tests in 4 configurations combining two upper body masses (either 0 or 3 kg) and two knee angles (0 or 20 degrees) at 40 kph (11 m/s) plus 2 tests at 9 m/s. Autopsies were performed on the lower limbs and an injury assessment was established. The findings of this study were first that the increase of the upper body mass resulted in more severe injuries, second that an initial flexion of the knee, corresponding to its natural position during the gait cycle, decreased the severity of the injuries, and third that based on the injury outcome, a test conducted with no upper body mass and the knee fully extended was as severe as a test conducted with a 3 kg upper body mass and an initial knee flexion of 20°.
Thermal and photochemical reactions of NO2 on chromium(III) oxide surfaces at atmospheric pressure.
Nishino, Noriko; Finlayson-Pitts, Barbara J
2012-12-05
While many studies of heterogeneous chemistry on Cr(2)O(3) surfaces have focused on its catalytic activity, less is known about chemistry on this surface under atmospheric conditions. We report here studies of the thermal and photochemical reactions of NO(2) on Cr(2)O(3) at one atm in air. In order to follow surface species, the interaction of 16-120 ppm NO(2) with a 15 nm Cr(2)O(3) thin film deposited on a germanium crystal was monitored in a flow system using attenuated total reflectance (ATR) coupled to a Fourier transform infrared (FTIR) spectrometer. Gas phase products were monitored in the effluent of an ~285 ppm NO(2)-air mixture that had passed over Cr(2)O(3) powder in a flow system. A chemiluminescence NO(y) analyzer, a photometric O(3) analyzer and a long-path FTIR spectrometer were used to probe the gaseous products. In the absence of added water vapor, NO(2) formed nitrate (NO(3)(-)) ions coordinated to Cr(3+). These surface coordinated NO(3)(-) were reversibly solvated by water under humid conditions. In both dry and humid cases, nitrate ions decreased during irradiation of the surface at 302 nm, and NO and NO(2) were generated in the gas phase. Under dry conditions, NO was the major gaseous product while NO(2) was the dominant species in the presence of water vapor. Heating of the surface after exposure to NO(2) led to the generation of both NO(2) and NO under dry conditions, but only NO(2) in the presence of water vapor. Elemental chromium incorporated into metal alloys such as stainless steel is readily oxidized in contact with ambient air, forming a chromium-rich metal oxide surface layer. The results of these studies suggest that active photo- and thermal chemistry will occur when boundary layer materials containing chromium(III) or chromium oxide such as stainless steel, roofs, automobile bumpers etc. are exposed to NO(2) under tropospheric conditions.
Design of crashworthy structures with controlled behavior in HCA framework
NASA Astrophysics Data System (ADS)
Bandi, Punit
The field of crashworthiness design is gaining more interest and attention from automakers around the world due to increasing competition and tighter safety norms. In the last two decades, topology and topometry optimization methods from structural optimization have been widely explored to improve existing designs or conceive new designs with better crashworthiness. Although many gradient-based and heuristic methods for topology- and topometry-based crashworthiness design are available these days, most of them result in stiff structures that are suitable only for a set of vehicle components in which maximizing the energy absorption or minimizing the intrusion is the main concern. However, there are some other components in a vehicle structure that should have characteristics of both stiffness and flexibility. Moreover, the load paths within the structure and potential buckle modes also play an important role in efficient functioning of such components. For example, the front bumper, side frame rails, steering column, and occupant protection devices like the knee bolster should all exhibit controlled deformation and collapse behavior. The primary objective of this research is to develop new methodologies to design crashworthy structures with controlled behavior. The well established Hybrid Cellular Automaton (HCA) method is used as the basic framework for the new methodologies, and compliant mechanism-type (sub)structures are the highlight of this research. The ability of compliant mechanisms to efficiently transfer force and/or motion from points of application of input loads to desired points within the structure is used to design solid and tubular components that exhibit controlled deformation and collapse behavior under crash loads. In addition, a new methodology for controlling the behavior of a structure under multiple crash load scenarios by adaptively changing the contributions from individual load cases is developed. Applied to practical design problems, the results demonstrate that the methodologies provide a practical tool to aid the design engineer in generating design concepts for crashworthy structures with controlled behavior. Although developed in the HCA framework, the basic ideas behind these methods are generic and can be easily implemented with other available topology- and topometry-based optimization methods.
Basic forensic identification of artificial leather for hit-and-run cases.
Sano, Tetsuya; Suzuki, Shinichi
2009-11-20
Single fibers retrieved from a victim's garments and adhered to the suspect's automobile have frequently been used to prove the relationship between victim and suspect's automobile. Identification method for single fiber discrimination has already been conducted. But, a case was encountered requiring discrimination of artificial leather fragments retrieved from the victim's bag and fused fibers from the bumper of the suspect's automobile. In this report, basic studies were conducted on identification of artificial leathers and single fibers from leather materials. Fiber morphology was observed using scanning electron microscopy (SEM), color of these leather sheets was evaluated by microspectrophotometry (MSP), the leather components were measured by infrared micro spectrometry (micro-FT-IR) and the inorganic contents were ascertained by micro-X-ray fluorescence spectrometry (micro-XRF). These two methods contribute to other analytical methods too, in the case of utilized single fiber analytical methods. The combination of these techniques showed high potential of discrimination ability in forensic examinations of these artificial leather samples. In regard with smooth surface artificial leather sheet samples, a total of 182 sheets were obtained, including 177 colored sheets directly from 10 of 24 manufacturers in Japan, and five of them were purchased at retail circulation products. Nine samples of suede-like artificial leather were obtained, 6 of them were supplied from 2 manufacturers and 3 sheets were purchased as retailing product. Single fibers from the smooth surface artificial leather sheets showed characteristic for surface markings, and XRF could effectively discriminate between these sheets. The combination of results of micro-FT-IR, color evaluation by MSP and the contained inorganic elements by XRF enabled to discriminate about 92% of 15,576 pairs comparison. Five smooth surface samples form retailing products were discriminated by their chemical composition into four categories, and in addition color information to this result, they were clearly distinguished. Suede-like artificial leather sheets showed characteristic extra-fine fibers on their surface by the observation of SEM imaging, providing high discriminating ability, in regard with suede-like artificial leather sheets were divided into three categories by micro-FT-IR, and the combination of these results and color evaluation information, it was possible to discriminate all the nine suede-like artificial leather sheets examined.
Single endoscopist-performed percutaneous endoscopic gastrostomy tube placement
Erdogan, Askin
2013-01-01
AIM: To investigate whether single endoscopist-performed percutaneous endoscopic gastrostomy (PEG) is safe and to compare the complications of PEG with those reported in the literature. METHODS: Patients who underwent PEG placement between June 2001 and August 2011 at the Baskent University Alanya Teaching and Research Center were evaluated retrospectively. Patients whose PEG was placed for the first time by a single endoscopist were enrolled in the study. PEG was performed using the pull method. All of the patients were evaluated for their indications for PEG, major and minor complications resulting from PEG, nutritional status, C-reactive protein (CRP) levels and the use of antibiotic treatment or antibiotic prophylaxis prior to PEG. Comorbidities, rates, time and reasons for mortality were also evaluated. The reasons for PEG removal and PEG duration were also investigated. RESULTS: Sixty-two patients underwent the PEG procedure for the first time during this study. Eight patients who underwent PEG placement by 2 endoscopists were not enrolled in the study. A total of 54 patients were investigated. The patients’ mean age was 69.9 years. The most common indication for PEG was cerebral infarct, which occurred in approximately two-thirds of the patients. The mean albumin level was 3.04 ± 0.7 g/dL, and 76.2% of the patients’ albumin levels were below the normal values. The mean CRP level was high in 90.6% of patients prior to the procedure. Approximately two-thirds of the patients received antibiotics for either prophylaxis or treatment for infections prior to the PEG procedure. Mortality was not related to the procedure in any of the patients. Buried bumper syndrome was the only major complication, and it occurred in the third year. In such case, the PEG was removed and a new PEG tube was placed via surgery. Eight patients (15.1%) experienced minor complications, 6 (11.1%) of which were wound infections. All wound infections except one recovered with antibiotic treatment. Two patients had bleeding from the PEG site, one was resolved with primary suturing and the other with fresh frozen plasma transfusion. CONCLUSION: The incidence of major and minor complications is in keeping with literature. This finding may be noteworthy, especially in developing countries. PMID:23864780
Radiometric calibration status of Landsat-7 and Landsat-5
Barsi, J.A.; Markham, B.L.; Helder, D.L.; Chander, G.
2007-01-01
Launched in April 1999, Landsat-7 ETM+ continues to acquire data globally. The Scan Line Corrector in failure in 2003 has affected ground coverage and the recent switch to Bumper Mode operations in April 2007 has degraded the internal geometric accuracy of the data, but the radiometry has been unaffected. The best of the three on-board calibrators for the reflective bands, the Full Aperture Solar Calibrator, has indicated slow changes in the ETM+, but this is believed to be due to contamination on the panel rather then instrument degradation. The Internal Calibrator lamp 2, though it has not been used regularly throughout the whole mission, indicates smaller changes than the FASC since 2003. The changes indicated by lamp 2 are only statistically significant in band 1, circa 0.3% per year, and may be lamp as opposed to instrument degradations. Regular observations of desert targets in the Saharan and Arabian deserts indicate the no change in the ETM+ reflective band response, though the uncertainty is larger and does not preclude the small changes indicated by lamp 2. The thermal band continues to be stable and well-calibrated since an offset error was corrected in late-2000. Launched in 1984, Landsat-5 TM also continues to acquire global data; though without the benefit of an on-board recorder, data can only be acquired where a ground station is within range. Historically, the calibration of the TM reflective bands has used an onboard calibration system with multiple lamps. The calibration procedure for the TM reflective bands was updated in 2003 based on the best estimate at the time, using only one of the three lamps and a cross-calibration with Landsat-7 ETM+. Since then, the Saharan desert sites have been used to validate this calibration model. Problems were found with the lamp based model of up to 13% in band 1. Using the Saharan data, a new model was developed and implemented in the US processing system in April 2007. The TM thermal band was found to have a calibration offset error of 0.092 W/m 2 sr ??m (0.68K at 300K) based on vicarious calibration data between 1999 and 2006. The offset error was corrected in the US processing system on April 2007 for all data acquired since April 1999.
Cratering Equations for Zinc Orthotitanate Coated Aluminum
NASA Technical Reports Server (NTRS)
Hyde, James; Christiansen, Eric; Liou, Jer-Chyi; Ryan, Shannon
2009-01-01
The final STS-125 servicing mission (SM4) to the Hubble Space Telescope (HST) in May of 2009 saw the return of the 2nd Wide Field Planetary Camera (WFPC2) aboard the shuttle Discovery. This hardware had been in service on HST since it was installed during the SM1 mission in December of 1993 yielding one of the longest low Earth orbit exposure times (15.4 years) of any returned space hardware. The WFPC2 is equipped with a 0.8 x 2.2 m radiator for thermal control of the camera electronics (Figure 1). The space facing surface of the 4.1 mm thick aluminum radiator is coated with Z93 zinc orthotitanate thermal control paint with a nominal thickness of 0.1 0.2 mm. Post flight inspections of the radiator panel revealed hundreds of micrometeoroid/orbital debris (MMOD) impact craters ranging in size from less than 300 to nearly 1000 microns in diameter. The Z93 paint exhibited large spall areas around the larger impact sites (Figure 2) and the craters observed in the 6061-T651 aluminum had a different shape than those observed in uncoated aluminum. Typical hypervelocity impact craters in aluminum have raised lips around the impact site. The craters in the HST radiator panel had suppressed crater lips, and in some cases multiple craters were present instead of a single individual crater. Humes and Kinard observed similar behavior after the WFPC1 post flight inspection and assumed the Z93 coating was acting like a bumper in a Whipple shield. Similar paint behavior (spall) was also observed by Bland2 during post flight inspection of the International Space Station (ISS) S-Band Antenna Structural Assembly (SASA) in 2008. The SASA, with similar Z93 coated aluminum, was inspected after nearly 4 years of exposure on the ISS. The multi-crater phenomena could be a function of the density, composition, or impact obliquity angle of the impacting particle. For instance, a micrometeoroid particle consisting of loosely bound grains of material could be responsible for creating the multiple craters. Samples were obtained from the HST largest craters for examination by electron microscope equipped with x-ray spectrometers to determine impactor source (micrometeoroid or orbital debris). In an attempt to estimate the MMOD particle diameters that produced these craters, this paper will present equations for spall diameter, crater depth and crater diameter in Z93 coated aluminum. The equations will be based on hypervelocity impact tests of Z93 painted aluminum at the NASA White Sands Test Facility. Equations inputs for velocities beyond the testable regime are expected from hydrocode simulations of Z93 coated aluminum using CTH and ANSYS AUTODYN.
Characteristics of Whipple Shield Performance in the Shatter Regime
NASA Technical Reports Server (NTRS)
Ryan, Shannon; Bjorkman, Michael; Christiansen, Eric L.
2009-01-01
Between the onset of projectile fragmentation and the assumption of rear wall failure due to an impulsive load, multi-wall ballistic limit equations are linearly interpolated to provide reasonable yet conservative predictions of perforation thresholds with conveniently simple mathematics. Although low velocity and hypervelocity regime predictions are based on analytical expressions, there is no such scientific foundation for predictions in the intermediate (or shatter) regime. As the debris flux in low earth orbit (LEO) becomes increasingly dominated by manmade pollution, the profile of micrometeoroid and orbital debris (MMOD) risk shifts continually towards lower velocities. For the International Space Station (ISS), encounter velocities below 7 km/s now constitute approximately 50% of the penetration risk. Considering that the transition velocity from shatter to hypervelocity impact regimes described by common ballistic limit equations (e.g. new non-optimum Whipple shield equation [1]) occurs at 7 km/s, 50% of station risk is now calculated based on failure limit equations with little analytical foundation. To investigate projectile and shield behavior for impact conditions leading to projectile fragmentation and melt, a series of hypervelocity impact tests have been performed on aluminum Whipple shields. In the experiments projectile diameter, bumper thickness, and shield spacing were kept constant, while rear wall thickness was adjusted to determine spallation and perforation limits at various impact velocities and angles. The results, shown in Figure 1 for normal and 45 impacts, demonstrated behavior that was not sufficiently described by the simplified linear interpolation of the NNO equation (also shown in Figure 1). Hopkins et al. [2] investigated the performance of a nominally-identical aluminum Whipple shield, identifying the effects of phase change in the shatter regime. The results (conceptually represented in Figure 2) were found to agree well with those obtained in this study at normal incidence, suggesting that shielding performance in the shatter regime could be well described by considering more complex phase conditions than currently implemented in most BLEs. Furthermore, evidence of these phase effects were found in the oblique test results, providing the basis for an empirical description of these effects that can be applied in MMOD risk assessment software. In this paper, results of the impact experiments are presented, and characteristics of target damage are evaluated. A comparison of intermediate velocity impact failure mechanisms in current BLEs are discussed and compared to the findings of the experimental study. Risk assessment calculations have been made on a simplified structure using currently implemented penetration equations and predicted limits from the experimental program, and the variation in perceived mission risk is discussed. It was found that ballistic limit curves that explicitly incorporated phase change effects within the intermediate regime lead to a decrease in predicted MMOD risk for ISS-representative orbits. When considered for all Whipple-based shielding configurations onboard the ISS, intermediate phase change effects could lead to significant variations in predicted mission risk.
Boddula, Madhav R; Adamson, Gregory J; Gupta, Akash; McGarry, Michelle H; Lee, Thay Q
2012-04-01
Both simple and mattress repair techniques have been utilized with success for type II superior labral anterior-posterior (SLAP) lesions; however, direct anatomic and biomechanical comparisons of these techniques have yet to be clearly demonstrated. For type II SLAP lesions, the mattress suture repair technique will result in greater labral height and better position on the glenoid face and exhibit stronger biomechanical characteristics, when cyclically loaded and loaded to failure through the biceps, compared with the simple suture repair technique. Controlled laboratory study. Six matched pairs of cadaveric shoulders were dissected, and a clock face was created on the glenoid from 9 o'clock (posterior) to 3 o'clock (anterior). For the intact specimen, labral height and labral distance from the glenoid edge were measured using a MicroScribe. A SLAP lesion was then created from 10 o'clock to 2 o'clock. Lesions were repaired with two 3.0-mm BioSuture-Tak anchors placed at 11 o'clock and 1 o'clock. For each pair, a mattress repair was used for one shoulder, and a simple repair was used for the contralateral shoulder. After repair, labral height and labral distance from the glenoid edge were again measured. The specimens were then cyclically loaded and loaded to failure through the biceps using an Instron machine. A paired t test was used for statistical analysis. After mattress repair, a significant increase in labral height occurred compared with intact from 2.5 ± 0.3 mm to 4.3 ± 0.3 mm at 11 o'clock (P = .013), 2.7 ± 0.5 mm to 4.2 ± 0.7 mm at 12:30 o'clock (P = .007), 3.1 ± 0.5 mm to 4.2 ± 0.7 mm at 1 o'clock (P = .006), and 2.8 ± 0.7 mm to 3.7 ± 0.8 mm at 1:30 o'clock (P = .037). There was no significant difference in labral height between the intact condition and after simple repair at any clock face position. Labral height was significantly increased in the mattress repairs compared with simple repairs at 11 o'clock (mean difference, 2.0 mm; P = .008) and 12:30 o'clock (mean difference, 1.3 mm; P = .044). Labral distance from the glenoid edge was not significantly different between techniques. No difference was observed between the mattress and simple repair techniques for all biomechanical parameters, except the simple technique had a higher load and energy absorbed at 2-mm displacement. The mattress technique created a greater labral height while maintaining similar biomechanical characteristics compared with the simple repair, with the exception of load and energy absorbed at 2-mm displacement, which was increased for the simple technique. Mattress repair for type II SLAP lesions creates a higher labral bumper compared with simple repairs, while both techniques resulted in similar biomechanical characteristics.
Secondary impact hazard assessment
NASA Technical Reports Server (NTRS)
1986-01-01
A series of light gas gun shots (4 to 7 km/sec) were performed with 5 mg nylon and aluminum projectiles to determine the size, mass, velocity, and spatial distribution of spall and ejecta from a number of graphite/epoxy targets. Similar determinations were also performed on a few aluminum targets. Target thickness and material were chosen to be representative of proposed Space Station structure. The data from these shots and other information were used to predict the hazard to Space Station elements from secondary particles resulting from impacts of micrometeoroids and orbital debris on the Space Station. This hazard was quantified as an additional flux over and above the primary micrometeoroid and orbital debris flux that must be considered in the design process. In order to simplify the calculations, eject and spall mass were assumed to scale directly with the energy of the projectile. Other scaling systems may be closer to reality. The secondary particles considered are only those particles that may impact other structure immediately after the primary impact. The addition to the orbital debris problem from these primary impacts was not addressed. Data from this study should be fed into the orbital debris model to see if Space Station secondaries make a significant contribution to orbital debris. The hazard to a Space Station element from secondary particles above and beyond the micrometeoroid and orbital debris hazard is categorized in terms of two factors: (1) the 'view factor' of the element to other Space Station structure or the geometry of placement of the element, and (2) the sensitivity to damage, stated in terms of energy. Several example cases were chosen, the Space Station module windows, windows of a Shuttle docked to the Space Station, the habitat module walls, and the photovoltaic solar cell arrays. For the examples chosen the secondary flux contributed no more than 10 percent to the total flux (primary and secondary) above a given calculated critical energy. A key assumption in these calculations is that above a certain critical energy, significant damage will be done. This is not true for all structures. Double-walled, bumpered structures are an example for which damage may be reduced as energy goes up. The critical energy assumption is probably conservative, however, in terms of secondary damage. To understand why the secondary impacts seem to, in general, contribute less than 10 percent of the flux above a given critical energy, consider the case of a meteoroid impact of a given energy on a fixed, large surface. This impact results in a variety of secondary particles, all of which have much less energy than the original impact. Conservation of energy prohibits any other situation. Thus if damage is linked to a critical energy of a particle, the primary flux will always deliver particles of much greater energy. Even if all the secondary particles impacted other Space Station structures, none would have a kinetic energy more than a fraction of the primary impact energy.
INTERGALACTIC 'PIPELINE' FUNNELS MATTER BETWEEN COLLIDING GALAXIES
NASA Technical Reports Server (NTRS)
2002-01-01
This visible-light picture, taken by NASA's Hubble Space Telescope, reveals an intergalactic 'pipeline' of material flowing between two battered galaxies that bumped into each other about 100 million years ago. The pipeline [the dark string of matter] begins in NGC 1410 [the galaxy at left], crosses over 20,000 light-years of intergalactic space, and wraps around NGC 1409 [the companion galaxy at right] like a ribbon around a package. Although astronomers have taken many stunning pictures of galaxies slamming into each other, this image represents the clearest view of how some interacting galaxies dump material onto their companions. These results are being presented today at the 197th meeting of the American Astronomical Society in San Diego, CA. Astronomers used the Space Telescope Imaging Spectrograph to confirm that the pipeline is a continuous string of material linking both galaxies. Scientists believe that the tussle between these compact galaxies somehow created the pipeline, but they're not certain why NGC 1409 was the one to begin gravitationally siphoning material from its partner. And they don't know where the pipeline begins in NGC 1410. More perplexing to astronomers is that NGC 1409 is seemingly unaware that it is gobbling up a steady flow of material. A stream of matter funneling into the galaxy should have fueled a spate of star birth. But astronomers don't see it. They speculate that the gas flowing into NGC 1409 is too hot to gravitationally collapse and form stars. Astronomers also believe that the pipeline itself may contribute to the star-forming draught. The pipeline, a pencil-thin, 500 light-year-wide string of material, is moving a mere 0.02 solar masses of matter a year. Astronomers estimate that NGC 1409 has consumed only about a million solar masses of gas and dust, which is not enough material to spawn some of the star-forming regions seen in our Milky Way. The low amount means that there may not be enough material to ignite star birth in NGC 1409, either. The glancing blow between the galaxies was enough, however, to toss stars deep into space and ignite a rash of star birth in NGC 1410. The arms of NGC 1410, an active, gas-rich spiral galaxy classified as a Seyfert, are awash in blue, the signature color of star-forming regions. The bar of material bisecting the center of NGC 1409 also is a typical byproduct of galaxy collisions. Astronomers expect more fireworks to come. The galaxies are doomed to continue their game of 'bumper cars,' hitting each other and moving apart several times until finally merging in another 200 million years. The galaxies' centers are only 23,000 light-years apart, which is slightly less than Earth's distance from the center of the Milky Way. They are bound together by gravity, orbiting each other at 670,000 miles an hour (1 million kilometers an hour). The galaxies reside about 300 million light-years from Earth in the constellation Taurus. The Hubble picture was taken Oct. 25, 1999. Credits: NASA, William C. Keel (University of Alabama, Tuscaloosa)
Computational Fluid Dynamics (CFD) Simulations of a Humvee Airdropped from Aircraft
NASA Astrophysics Data System (ADS)
Reyes, Phillip M.
Military airdrop is a means of transporting and delivering cargo to inaccessible locales faster and more efficiently. The Humvee, an all-terrain truck, is one such payload that the U.S. Army drops routinely. Here, interesting physics occurs both structurally and aerodynamically. From a fluid dynamics and trajectory standpoint, determining the aerodynamic forces and moments acting on the parachute and payload is crucial particularly for trajectory prediction. This study primarily used Computational Fluid Dynamics (CFD) to simulate the aerodynamics of an airdrop Humvee model in two regimes of fall, namely, right after clearing the aircraft ramp, and during descent under parachute. This study was performed at a Reynolds number of 3.07x10. 6 and at an airspeedof 9.144m/s (30ft/s). The first humvee part of the study analyzed the aerodynamic coefficients drag, lift, and pitching moment over a 360 degree range of pitch angles for the Humvee configured for extraction. The second set of humvee simulations focused on the aerodynamic coefficients at pitch angles of -40 degrees to +40 degrees with the platform and vehicle configured for descent under parachute. The Humvee after ramp tip-off has a parachute pack on its hood, but lacks one during the descent phase. The numerical data was compared with the results of geometries from previous studies. These geometries include: the flat plate, Type-V LVADS and 10K-JPADS containers, and a cargo-carrying platform outfitted with a bumper. Our results clearly show the effects of the many angular features that characterize the shape of a Humvee in comparison to those of a simple cuboid, particularly with regards to the loss of lift in a sub-range of pitch angle (-45 degrees to -180 degrees). First, the aerodynamic coefficients were calculated over one full-revolution of the humvee (-180 degrees to +180 degrees static pitch angles with respect to the humvee's platform) best matched in lift, drag, and moment those of the type V LVADS payload analyzed in a previous study. Here, three important findings emerge: (1) Lift is not symmetric with positive to negative angles and more so, lift is negligible at pitch angles less than -45 degrees (2) the humvee-platofrm may be considered stable when oriented perpendicular to the flow (both 90 degrees and -90 degrees); (3) there is a range of pitch angle (52 degrees to 117 degrees) where the lift coefficient is linearly dependent on angle of attack. This is the orientation at which the oncoming flow meets the platform first (i.e. before moving past the humvee's body), thereby producing a forward-projected area similar to that of a flat-plate. The second part of the study (descent under parachute) also shows a similar result. Negative pitch angles show a continual increase in lift and moment coefficients, whereas for positive pitch angles at 30 degrees and 40 degrees the negative lift values do not decrease as fast as earlier positive pitch angles. This difference is explained with pressure coefficient curves. Validation of our CFD modeling is also discussed, with the presentation of numerical results generated on benchmark cases such as the flows about flat plates held at various pitch angles.
NASA Technical Reports Server (NTRS)
Hill, S. A.
1994-01-01
BUMPERII is a modular program package employing a numerical solution technique to calculate a spacecraft's probability of no penetration (PNP) from man-made orbital debris or meteoroid impacts. The solution equation used to calculate the PNP is based on the Poisson distribution model for similar analysis of smaller craft, but reflects the more rigorous mathematical modeling of spacecraft geometry, orientation, and impact characteristics necessary for treatment of larger structures such as space station components. The technique considers the spacecraft surface in terms of a series of flat plate elements. It divides the threat environment into a number of finite cases, then evaluates each element of each threat. The code allows for impact shielding (shadowing) of one element by another in various configurations over the spacecraft exterior, and also allows for the effects of changing spacecraft flight orientation and attitude. Four main modules comprise the overall BUMPERII package: GEOMETRY, RESPONSE, SHIELD, and CONTOUR. The GEOMETRY module accepts user-generated finite element model (FEM) representations of the spacecraft geometry and creates geometry databases for both meteoroid and debris analysis. The GEOMETRY module expects input to be in either SUPERTAB Universal File Format or PATRAN Neutral File Format. The RESPONSE module creates wall penetration response databases, one for meteoroid analysis and one for debris analysis, for up to 100 unique wall configurations. This module also creates a file containing critical diameter as a function of impact velocity and impact angle for each wall configuration. The SHIELD module calculates the PNP for the modeled structure given exposure time, operating altitude, element ID ranges, and the data from the RESPONSE and GEOMETRY databases. The results appear in a summary file. SHIELD will also determine the effective area of the components and the overall model, and it can produce a data file containing the probability of penetration values per surface area for each element in the model. The SHIELD module writes this data file in either SUPERTAB Universal File Format or PATRAN Neutral File Format so threat contour plots can be generated as a post-processing feature of the FEM programs SUPERTAB and PATRAN. The CONTOUR module combines the functions of the RESPONSE module and most of the SHIELD module functions allowing determination of ranges of PNP's by looping over ranges of shield and/or wall thicknesses. A data file containing the PNP's for the corresponding shield and vessel wall thickness is produced. Users may perform sensitivity studies of two kinds. The effects of simple variations in orbital time, surface area, and flux may be analyzed by making changes to the terms in the equation representing the average number of penetrating particles per unit time in the PNP solution equation. The package analyzes other changes, including model environment, surface area, and configuration, by re-running the solution sequence with new GEOMETRY and RESPONSE data. BUMPERII can be run with no interactive output to the screen during execution. This can be particularly useful during batch runs. BUMPERII is written in FORTRAN 77 for DEC VAX series computers running under VMS, and was written for use with the finite-element model code SUPERTAB or PATRAN as both a pre-processor and a post-processor. Use of an alternate FEM code will require either development of a translator to change data format or modification of the GEOMETRY subroutine in BUMPERII. This program is available in DEC VAX BACKUP format on a 9-track 1600 BPI magnetic tape (standard distribution media) or on TK50 tape cartridge. The original BUMPER code was developed in 1988 with the BUMPERII revisions following in 1991 and 1992. SUPERTAB is a former name for I-DEAS. I-DEAS Finite Element Modeling is a trademark of Structural Dynamics Research Corporation. DEC, VAX, VMS and TK50 are trademarks of Digital Equipment Corporation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coppola, Anthony; Faruque, Omar; Truskin, James F
As automotive fuel economy requirements increase, the push for reducing overall vehicle weight will likely include the consideration of materials that have not previously been part of mainstream vehicle design and manufacturing, including carbon fiber composites. Vehicle manufacturers currently rely on computer-aided engineering (CAE) methods as part of the design and development process, so going forward, the ability to accurately and predictably model carbon fiber composites will be necessary. If composites are to be used for structural components, this need applies to both, crash and quasi-static modeling. This final report covers the results of a five-year, $6.89M, 50% cost-shared researchmore » project between Department of Energy (DOE) and the US Advanced Materials Partnership (USAMP) under Cooperative Agreement DE-EE-0005661 known as “Validation of Material Models for Automotive Carbon Fiber Composite Structures Via Physical and Crash Testing (VMM).” The objective of the VMM Composites Project was to validate and assess the ability of physics-based material models to predict crash performance of automotive primary load-carrying carbon fiber composite structures. Simulation material models that were evaluated included micro-mechanics based meso-scale models developed by the University of Michigan (UM) and micro-plane models by Northwestern University (NWU) under previous collaborations with the DOE and Automotive Composites Consortium/USAMP, as well as five commercial crash codes: LS-DYNA, RADIOSS, VPS/PAM-CRASH, Abaqus, and GENOA-MCQ. CAE predictions obtained from seven organizations were compared with experimental results from quasi-static testing and dynamic crash testing of a thermoset carbon fiber composite front-bumper and crush-can (FBCC) system gathered under multiple loading conditions. This FBCC design was developed to demonstrate progressive crush, virtual simulation, tooling, fabrication, assembly, non-destructive evaluation and crash testing advances in order to assess the correlation of the predicted results to the physical tests. The FBCC was developed to meet a goal of 30-35% mass reduction while aiming for equivalent energy absorption as a steel component for which baseline experimental results were obtained from testing in the same crash modes. The project also evaluated crash performance of thermoplastic composite structures fabricated from commercial prepreg materials and low cost carbon fiber sourced from Oak Ridge National Laboratory. The VMM Project determined that no set of predictions from a CAE supplier were found to be universally accurate among all the six crash modes evaluated. In general, crash modes that were most dependent on the properties of the prepreg were more accurate than those that were dependent on the behavior of the joints. The project found that current CAE modeling methods or best practices for carbon fiber composites have not achieved standardization, and accuracy of CAE is highly reliant on the experience of its users. Coupon tests alone are not sufficient to develop an accurate material model, but it is necessary to bridge the gap between the coupon data and performance of the actual structure with a series of subcomponent level tests. Much of the unreliability of the predictions can be attributed to shortcomings in our ability to mathematically link the effects of manufacturing and material variability into the material models. This is a subject of ongoing research in the industry. The final report is organized by key technical tasks to describe how the validation project developed, modeled and compared crash data obtained on the composite FBCC to the multiple sets of CAE predictions. Highlights of the report include a discussion of the quantitative comparison between predictions and experimental data, as well as an in-depth discussion of remaining technological gaps that exist in the industry, which are intended to spur innovations and improvements in CAE technology.« less
Safer Vehicles for People and the Planet: Letter to the Editor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wenzel, Thomas P; Wenzel, Thomas P; Ross, Marc
Letter to the Editors from Leonard Evans, Bloomfield Hills, MI: Single-vehicle crashes, which account for half of occupant fatalities, are not mentioned in 'Safer Vehicles for People and the Planet', by Thomas P. Wenzel and Marc Ross (March-April). Simple physics shows that in such crashes risk declines as vehicle mass increases. The authors write 'driving imported luxury cars carries extremely low risk, for reasons that are not obvious'. The reasons are obvious--the cars are purchased by low-risk drivers. If they swapped vehicles with drivers of sports cars (which have high risk), the risks would stick with the drivers, not themore » vehicles. The article reflects the American belief that death on our roads can be substantially reduced by making vehicles in which it is safer to crash. From 1979 through 2002, Great Britain, Canada and Australia reduced fatalities by an average of 49 percent, compared with 16 percent in the U.S. Accumulating the differences over this time shows that by merely matching the safety performance of these other countries, about 200,000 fewer Americans would have died. These trends continue. In 2006 the U.S. recorded 42,642 traffic deaths, a modest 22 percent decline from our all-time high. Sweden recorded 445, a reduction of 66 percent from their all-time high. The obsessive focus on vehicles rather than on countermeasures that scientific research shows substantially reduce risk is at the core of our dramatic safety failure. The only way to substantially reduce deaths is to reduce the risk of crashing, not to make it safer to crash. The response from Drs. Wenzel and Ross: Of course Dr. Evans is correct in stating that driver behavior influences crash risk. In our article we made clear that our estimates of risk include how well a vehicle/driver combination avoids a crash, as well as how crash-worthy a vehicle (and robust a driver) is once a crash occurs. We also analyzed two variables that can account for driver behavior: the fraction of all driver fatalities that are young men, and a 'bad driver' rating that combines information about the current crash (drug or alcohol involvement, driving without a license, or reckless driving) as well as the operator's driving record for the previous three years. For example, the high risks of sports cars, and the low risks of minivans, are clearly influenced by who drives these types of vehicles (36 percent young males and 0.77 bad driver rating for sports cars, vs. 4 percent and 0.21 for minivans; the average values for all types of cars are 20 percent and 0.50). On the other hand, we were surprised to find that the imported luxury cars, with the lowest risks, have only average drivers (21 percent young males, 0.57 bad driver rating). That is the basis for our conclusion that the design of imported luxury vehicles, or at least specific safety features on them, overcome risky behavior taken by their drivers. The safety of vehicles has greatly improved over the years. In our studies we have found several examples of models that greatly reduced their risks over time; for example, the Ford Focus has a much better risk to its drivers (118) than the Ford Escort it replaced (148). Our data indicate that more young males drive the Focus (21 percent) than the Escort (15 percent), and that Focus drivers are perhaps slightly more risky (0.50 vs. 0.44 bad driver rating). Clearly vehicle design does not play as small a role in vehicle safety as Dr. Evans suggests. Dr. Evans asserts that we ignore single-vehicle crashes and that simple physics dictates that vehicle mass provides safety in single-vehicle crashes. By itself, additional vehicle mass does provide some protection from rapid deceleration in crashes with a movable object, particularly for an unbelted occupant. However, when it comes to vehicle safety, our research by vehicle model indicates that there is essentially no relationship between car mass and risk, even in frontal crashes. In his own papers, Dr. Evans appears to admit that it is not clear whether mass, or size (specifically crush space) is inherent to vehicle safety. Additional research indicates that it is not size per se that protects in two-vehicle crashes, but how well the stiff structures on the vehicles are aligned. The auto manufacturing industry has voluntarily made design changes to their pickup trucks to increase the likelihood that truck and car bumpers will interact in a frontal crash, reducing the aggressivity of pickup trucks in recent years. Regarding the differences in experiences between the U.S. and other countries, it is important to keep in mind that the U.S. vehicle fleet is fairly unique; about half of U.S. vehicles are light duty trucks (pickups, SUVs and minivans), which many studies have shown are dangerous to other road users.« less
EDITORIAL: A physicist's journey to the centre of the Earth
NASA Astrophysics Data System (ADS)
Hipkin, Roger
1999-07-01
It is a paradox that, despite it being the planet on which all our experience is founded, the bulk Earth is as inaccessible as a remote galaxy. In South African diamond mines, man has penetrated about 3 km into the solid Earth; intact core from boreholes has been recovered from about 7 km and, in the Kola Peninsula of northern Russia, drill chippings have been sluiced up from about 13 km. Nevertheless, even if we had the resources to pepper the outer layer with exploratory boreholes, direct observation of the remaining 99% of the Earth's volume will always remain an impossibility. And yet we know some quite detailed properties of the interior of the Earth. Contrary to primitive cosmologies inspired by watching volcanoes erupt, and although below 2890 km there is a core of molten steel, we know that only in rare, shallow and isolated pockets are the rocks of the Earth's interior molten. The interior of the Earth is like an onion-skin: properties (density, electrical conductivity, sound speed etc) change mainly with depth. Taking the Earth's response to stress as one example, the material behaves like a brittle elastic solid only to depths of about 10-20 km. Below that, Earth materials exhibit the properties of both a solid and a liquid: to short-period effects like sound waves, they respond as a conventional solid but, when subjected to long-period stress, they can also flow like a liquid with a very high viscosity. Viscosity is initially controlled by the increasing mobility of atoms as temperature increases (viscosity decreases from about 1025 Pa s in the upper 20 km to about 1020 Pa s at a depth of 250 km); but atomic mobility is then offset by the counteracting effects of increasing pressure (viscosity increases to perhaps 1023 Pa s at 2500 km). We also have a quantitative physical picture of Earth behaviour stretching back over 4.5 billion years, despite having only 4500 years of recorded scientific observations about the Earth. Using the same physics that designed the platework of ships and bridges, we see the upper elastic layer of the Earth bending under the loads applied by mountains and ice sheets: about 11 000 years ago, a 2 km load of ice melted, and Scandinavia and northern Canada are still springing back into shape at about 10 mm per year. About 100 million years ago, the plate supporting North America and Europe fractured, and we can measure their continuing separation with lasers and microwaves at a few cm per year. We are now just able to make acoustic images of turbulent plumes churning up the Earth's deep interior as heat from radioactive decay is converted into the motion of convective overturn: the Earth is a heat engine! So how is all this `knowledge' possible when there are absolutely no direct observations of the interior of the Earth or its remote past? Over the course of the last few centuries, careful laboratory observations have identified patterns in the way natural materials behave which we now codify as the laws of physics. They enable us to construct a model of how materials would behave under more exotic conditions and at past and future times. As one example, we measure the rate at which radioactive atoms decay and identify that the half-life of a particular species is a `constant of nature', that is, we have so far found no ambient conditions that cause it to vary. With this experience, we measure radioactive isotopes in a rock to find the proportion of parent atoms remaining to the daughter atoms produced by its decay. Knowing the half-life makes the rock a natural clock with which to date an event in the remote past. In the special feature on Geophysics in this issue, we have picked just a few examples to show how basic physics - gravity, electricity, magnetism and sound - can be harnessed to investigate what we can never observe directly. `Antarctic seismology' is an example of the Earth being doubly remote: its surface as well as its interior are inaccessible. Here, practical fieldwork extending to distant parts of the globe must be combined with international collaboration. ` `Little g' revisited' illustrates how a global picture of the Earth's gravity field is being created by supplementing such ground-based measurements with remote-sensing from satellites. Satellites now form the main source of information about `The Earth's main magnetic field', the consequence of a vast dynamo within the molten iron core. For such global problems of the deep interior, the impossibility of making direct observations is absolute but cost can often be an equally strict limitation for much geophysical work. While we could in principle look for oil reservoirs or shallow regions where poison has contaminated the ground by digging it all up or drilling, this would be economically prohibitive. `Investigating brownfield sites with electrical resistivity' illustrates that, for the geophysicist, investigating the Earth's core and mapping subsurface chemical pollutants are aspects of the same problem - using basic physics to find out about the Earth's inaccessible interior. Editor's note. In this bumper issue of Physics Education we also have a trio of articles about absolutely nothing, showing that there is more to nothing than might be apparent to the casual eye!
hwhap_Ep28_3 Weeks in a Capsule
2018-01-19
Gary Jordan (Host): Houston, we have a podcast. Welcome to the official podcast of the NASA Johnson Space Center Episode 28, Three Weeks in a Capsule. I'm Gary Jordan, and I'll be your host today. So this is the podcast. We'll be bringing the experts. NASA scientists, engineers, astronauts, all to tell you the coolest information about what's going on here at NASA. So today we're talking about what it will be like to live and work in the Orion Capsule with Jessica Vos. She's a crew systems engineer here at the NASA Johnson Space Center in Houston, Texas, and we had a great discussion about how astronauts will operate in the Orion capsule for missions that can go up to three weeks. Like how they'll eat, sleep, exercise, work, and if needed be prepared for the worst. So with no further delay, let's go light speed and jump right ahead to our talk with Ms. Jessica Vos. Enjoy. [ Music ] Host: So living on Orion is going to be, it's going to be tough. How long are the missions that you're going to be living, if you were to say you're going to live on Orion for blank, what are you planning for? How long of a mission? Jessica Vos: The longest that we're really thinking, it's designed to do four crew for 21 days. The longest that we're really thinking, that will really work out, is probably in that like 15-, 16-day range. Host: Huh. Jessica Vos: Because once you start docking to DSG, you've facilities there, so you would just basically kind of shut down or close off the Orion and go use your habitat module. Host: Okay. Jessica Vos: The much bigger, spacious, better stuff, right. Host: Yeah. Jessica Vos: And this in thing, you're going to be on a transport vehicle when you're going that has some sort of a habitat kind of feature to it when you're going to Mars. Host: Right. Jessica Vos: So, the just Orion piece, probably the longest you'd really need to be living in there is, it's designed for 21 days. Host: Okay. And the 21 days takes into account in case something goes wrong and you need some extra time, or is it just the redundancy aspect of things? Jessica Vos: Well it was more like the sizing. Host: Sizing, okay. Jessica Vos: You can try to squeeze a mission in that's right up to your 21 days and then you just have no margin for, you know, anything, but-- Host: Yeah. Jessica Vos: But the size of all of the consumables and how much, you know, CO2 scrubbing and how much water you need and stuff, it's for four crew for 21 days. Host: Okay. So then more likely it'll be like a 16-day thing. Cool. So today let's talk about just Orion, living on it, and what that's going to look like. You know, like you said, the 21-day mission profile, it can support someone for 21 days and what that's going to look like if you were to live there for, you know, up to that much but probably like you said, shorter, 16 days, so let's start with Orion, like what, what is it. Because we talked with Najude and Morancy about this in a previous episode, but for those who didn't listen to it, let's talk about like what is Orion, what's the shape of it. Like if you were living in it, what's this house look like. Jessica Vos: Okay, so basically volume wise you're talking about maybe like a double minivan, you know. So like if you take the size of a minivan, if you've ever been on a road trip, you try to squeeze four to six people in a minivan, it can be kind of tight, but if you double that volume, that's kind of what we're talking about. It's about 300 cubic feet of space. We are talking about putting four people in, and the shape is very similar to what you saw in the Apollo days in terms of that cone capsule, right. Physics kind of dictates that in terms of when you're coming back from deep space, there's a lot of energy that needs to be released through the atmosphere, and particular blunt body shape does that really well. So you've got, you know, the wide bottom with the skinnier top makes it look like a little cone. So, very similar to that. Host: Okay, cool. But it sounds like, you said double minivan for four people, that's more space than I would think. Jessica Vos: Yeah, and, you know, what's even better about it is the fact that you've got all of the volume to work with once you're in microgravity. Host: That's right. Jessica Vos: You don't just have the floor space. You now have this really truly 3D space to do whatever you need to do in, so it's not just the four people in a double minivan in their seats and rocking around on the bottom of the car or being strapped in their seats, it's truly floating within that space, so. Host: Okay. So you got this double minivan sort of space, let's-- how about the lay of the land. I'm imaging the one in building nine is the mockup of it. Once you enter through that hatch, what are you looking at, like where are the seats, where are the screens, where is all that stuff? Jessica Vos: Yeah, so we are fortunate enough to have a full-scale Orion mockup here in building nine at Johnson Space Center, and the space vehicle mockup facility it's like a big playground for spacecraft. When we enter our mockup, you enter through the side hatch, and as you enter, you first step on a step. And when you get in, you'll see there's a little bit of a space between your foot and the seat pan, the leg pan of the seats for the crew. And there are four of those seats aligned two and two. So two of them kind of, they don't stack like lay on top of each other like bunk beds, it's not like that. But they're aligned two and two in like rows to your left. Host: Okay. Jessica Vos: If the crew were laying in their seats to see you as you come into the side hatch, they would need to turn their heads to the right. Host: Okay. Jessica Vos: So their feet-- Host: So the first, yeah, the first thing you see are their feet, and their heads are kind of towards the wall. Jessica Vos: Right, yep. Host: Okay. Jessica Vos: So their legs are kind of oriented towards the center of the spacecraft, and their heads are toward the outside so that their heads can line up pretty much directly underneath the displays and controls as well as the windows. Host: Oh. Jessica Vos: So without moving their head a whole lot, they have visibility to look out the windows for orientation during, you know, dynamic phases of flight and understanding where they are relative to the stars, through the window, and then they also have all of the information that they need to execute those maneuvers on the displays and controls right in front of them. It also is, a real interesting thing about that design of the seats, they don't have to do a whole lot of manipulation, like if you think about, oh, well why don't we do really super fancy touch screens. Well, if you're in a vibration environment like during launch, your hands are really heavy actually, and your fingers are going to be moving around if you unstrap them from that seat and then try to go touch the screen. Host: Right. Jessica Vos: So they much prefer, of course, the switches and the dials and the buttons, which we have on the outer edges of our displays and controls. We recently did some testing. It was just, I think it was last year, about this time last year, where we did a legibility under vibration test with the crew, and so you had the whole system of the seat, the suit, and the human all vibrating under what we would determine, what we had determined to be our launch loading condition, the vibration condition, and then they have to tell us basically are they able to read the screen and execute what they're supposed to be doing based on those commands under the vibration condition. So the whole point is that they're able to do what they need to be doing under all the dynamic phases of flight. So the seat is, the design is for that purpose. Host: All right. Yeah, I'm imagining like a, I don't know if you've ever been like in the car or something, you see the clock like going up and down, like the digital clock, and it's really hard to read, and you're like what time is it. Jessica Vos: And if you do need to reach and push the button next to the clock like can you, you know. Are you going to push the right one. Host: That's true, because when they're launched, you got all this weight on you. Jessica Vos: So then after that you got the, you got the screens. So then they have these buttons around the screens, right, that you can press? Host: Yep. So that's, and that's part of the design, right, three screens? Jessica Vos: Yes, that is part of the design. You've got two people monitoring those three screens, so you've got a little bit of that kind of ability for both people to operate both screens. Now, I would say two screens at a time. So that middle screen, you're going to get people being, reach and access wise, those two crew members, you know, copilot and pilot are going to be able to both see and touch at least those two screens in front of them, and then you kind of got the outer screens being monitored by one person at a time. Host: Okay. Jessica Vos: The switches are very important. That's what gives them that tactile feedback of knowing that they actually done something while they're wearing, while they have their gloves on. So it's easy for us, you know, with the fancy iPhones to just really gently feel a tap on the home screen button, right. Host: Yeah. Jessica Vos: But that's the same when you've got layers of a suit going around your hands, right. So for them to know that they indeed have actuated something, they really like that switch feel. And so there are specific designs around how those switches feel to the crew member to make sure that they know that they have in fact actuated what they were supposed to actuate. Host: Yeah. It's the space version of responsive design, where like, as if your phone, but a lot of other things to consider. Jessica Vos: Yep. Host: Awesome. So that's like the, that's the pilot area, and that's where you would, you would, I guess, quote unquote fly Orion, right. So then, so is the rest of the area that you're looking at, like you said when you go through the hatch, this whole area, is that the living area or is there more? Jessica Vos: So there is space that's up back behind their heads. Host: Okay. Jessica Vos: And, now recall that the ECLS wall, ECLS is environmental control and life support, so there's like a wall back there that houses all of that equipment, and then in front of that is a bunch of stowage, a bunch of webbing kind of material. Host: Yeah. Jessica Vos: Like you know kind carabineer or hook to different D-rings in places to kind of stow stuff in and kind of keep it stowed back there. Underneath the pallet, the floor, underneath the floor is more stowage. That is also where some of the avionics bays are, I believe, and then some of the other systems for the vehicle that humans require such as the waste management system. Host: Very important. Jessica Vos: Very important. So, yeah, somehow it all squeezes in there. Host: Okay. And that's really the, that's really what Orion is, is trying to, trying to get, you know, like this camper that you're going to be living in for 16, 21 days, whatever, and just squeeze all this stuff in that you need for all of that stuff, knowing that it's not like you can stop at a convenience store or gas station along the way to pick anything up. Jessica Vos: Exactly. In fact, as I speak to you this afternoon, there's a team of engineers at one of the off-site mockup facilities that are doing a stowage evaluation. So they're literally right now playing that 3D game of Tetris and trying to figure out where all this mass and stuff is going to go. Because you also have to think about the CG of the vehicle, both on launch and on landing, it's got to be very specific, so things have to be put in certain places. And then there's also another very good consideration or important consideration, and that is, with respect to reach and access with the crew coming home and going through this dynamic phase of flight, there are certain things that you're going to want them to be able to get to pretty much right away. So there's some stowage that is literally right on their seats. There's stowage of things that's right next to them or such that one particular crew member can get there in a very quick amount of time. So it's not like you can just put stuff wherever you want to. There's also consideration, right, for not storing things like food next to things like the [inaudible]. So it gets tricky, and so they redo these evaluations as the designs for all of this equipment, crew equipment matures. Host: All right. Yeah, I'm going to have to, I'm going to have to get some tips from you for my dad because to, how to pack a camper for a camping trip, to make it the most efficient way possible. He could definitely appreciate that because he's an expert packer, but not compared to an Orion crew system [inaudible]. Jessica Vos: Yeah, these guys have got it down, I'm telling you. Host: Wow, all right. So obviously, you know, you're maximizing the limited space that you have and thinking about every component about where things are stored and where things are, so, you know, the living portion of things, right. What is, what's the lay of the land for, you know, now you can get out of your seat, and it's time to go do stuff. Where is everything else? Like food. Jessica Vos: So there is a series of lockers both on that kind of ECLS wall that I was telling you about and a few more underneath the pallet on the floor, and I think portions of the food are stored in both of those places if I understand correctly. It could be that all of it maybe went in one of lockers underneath the seats now that I'm thinking about it, but they need to, they're each stored-- the way that the food is going to be stored is very similar to what we see currently on the space station, which is that they're flown up in very specific sized compartments. I think they call them CTBs, and they'll be organized either by crew member or by, you know, type of food that it is, and each of those gets put into a certain locker and given a certain, you know, spot to be. Host: Yeah. Jessica Vos: That's the same for a lot of the equipment actually. It's just, it's all going to be in a particular locker. There's a few different sizes of lockers and a few different kind of orientations, but it's all stowed away. I think more interestingly there is the exercise device, and the exercise device is this neat little box that is going to be, going to serve as the step to the side hatch as well. So in zero gravity, of course you don't need a step, right, to do anything with the side hatch. You're not using the side hatch. You really don't want that hatch to open on orbit. But on landing, when the crew is somewhat deconditioned after having been in microgravity for 16 to 21 days, they might need a step to get up and over that edge. So the idea is that this box that's taking up space serves two functions. It's going to be the step to allow the crew to get in and out, and the recovery crew as well, and it's the exercise device. And right now the exercise device is planned to be, it's kind of cool because it doesn't require any power. It's just a flywheel-based device that's got some smart settings to it that allow the crew to execute different prescriptions that the ASCRs give them. That's the astronaut strength and condition rehabilitation specialist I think. Host: Got to have acronyms. Jessica Vos: The ASCRs. They provide the exercise prescriptions, and that one box alone will allow the crew members to get at least 30 minutes of exercise activity that will challenge their cardiovascular systems and their musculoskeletal systems as required, so-- Host: All right. Jessica Vos: Yeah. Host: So a little tiny box, and it's kind of like a, I'm imagining a rowing machine, right, that you would see in the gym, kind of like that, but obviously more advanced so it can do aerobic and resistive exercise, meet all the needs that you need. Jessica Vos: Right. [00:19:52] Host: Because the space station right now has the advanced resistive exercise device-- Jessica Vos: Absolutely. Host: Which is like a big weightlifting machine. You don't have room for that. Jessica Vos: No, we don't have room for that. [laughter] Host: And it's got a treadmill, I mean, from what Nujoud said, you could potentially stand up, right, if you were to like touch the base, like there's enough room where you can stand up straight? Jessica Vos: Yes, yes. You can. I believe, I know I can, but I'm only five three. Host: Oh, okay. Jessica Vos: So I don't know that the, I believe the crew module is sized for I think up to a six four individual. Host: Wow. Jessica Vos: If I'm correct. So, yeah, you don't have to be particularly short. You will, you know, there is limits to which seat we can put you in if you are on that taller edge. Host: Oh. Jessica Vos: But, and I do believe that I think somebody at least up to six foot would be able to, like Nujoud said, stand in the center of the capsule. Host: Wow. Jessica Vos: But you're right, when you're rowing, you're still going to get into a standing stature position, but in zero gravity, we're going to have you do it through the center of the spacecraft. Host: So you're not going up to the tip of the cone, right, you're going, yeah. Jessica Vos: You're not going up, yeah, you're not going up to where the docking hatch is on the top at the very, at the tip, you're going to the other side of the spacecraft. So you're starting at the side hatch, right underneath the side hatch, and you're extending your body long out to the other side of the spacecraft. Host: Ah, okay. So that's, so that takes up a decent amount of real estate, right, that's the, that's the working out real estate. Jessica Vos: It sure does. Host: And where is everyone else while someone is working out? I guess they're all in the same room, right. Jessica Vos: Yeah, they absolutely are. And it's funny because when you think about how much time is really going to spent each day when you have four crew members doing at least 30 minutes each, it's like a couple hours that that person is going to be basically occupying a good chunk of the space while they exercise, and everyone else is going to have to be kind of staying out of the way, right. Host: Yeah. Jessica Vos: So it's going to be interesting. Host: Plus the noise, I'm thinking of a rowing machine, right. So plus the noise of rump, rump, for hours. Jessica Vos: Oh yeah, absolutely. That's a good topic actually. Host: Really? Jessica Vos: There are several acoustic requirements imposed on every system that goes into the cabin for just that reason. Like it's very hard to concentrate and focus and get real work done, right, if you are constantly, you know, having to deal with a buzz. You know how annoying that can be. Host: Yeah. Jessica Vos: So there are a lot of acoustic requirements placed on all of the different systems that have to be continuously operating, and yeah, the exercise device is one of them absolutely. Host: So there's an acoustic, it has to be, it can't exceed like this noise level or something. Jessica Vos: Yep. Host: Interesting. Jessica Vos: Yeah. Host: So have you simulated something, like an environment where people are living in Orion for a couple days already, or is that still to come, like so you can understand the acoustic environment and say, hey, that's annoying or something like that. Jessica Vos: So there hasn't been, there has not been to my knowledge any day in the life of type of tests specific to the Orion capsule. However, there have been a series of analogue tests being done in terms of the isolated environment. So right here at Johnson Space Center, the human research program owns the HERA, which is the Human Exploration Research Analogue. Host: Yeah. Jessica Vos: And they do study how humans behave in isolation and the effects on team dynamics, and they try to stress them out a little bit, right, and try to see how they can improve on the team dynamics basically. It's very BHP, behavioral health and performance oriented, not as much as hey, you know, is the Orion design adequate or sufficient. We haven't gotten to that point with the Orion design yet in terms of verification and validation. We will with EM1 and EM2. We've got sensors on the EM1 mission that uses the Orion capsule that will measure acoustics and radiation and all that good stuff. But in terms of the people aspect, we study it here through the human research program in HERA, and unfortunately the volume of that is just way beyond what-- it's huge in there. Host: Yeah. Jessica Vos: So they have way more volume in space to live and work in. Host: Yeah. Jessica Vos: The acoustics though I would say is probably one of the things that they do tweak to try to see if it stresses the crew out, but I couldn't speak to the results of that, but I'm sure that it's one of the things that they try to tweak, as a variable, to see what kind of impacts in terms of stress it has on the crew. Host: Definitely, we actually just had Lisa Spence and Paul Haugen here earlier today to talk about HERA, and by the time this comes out, I believe there's the HERA episode already, Space Habitats. Jessica Vos: Awesome. Host: So there should already be a little bit more anybody that, and I was picking her brain, but obviously there's still, there's still researching. They still have to collect the data-- Jessica Vos: Oh, yeah. Host: So they haven't, they haven't like, you know, consolidated everything into a published paper quite yet, and more to come, but absolutely, totally transferrable to an Orion environment. The human element to that. Jessica Vos: Yep, yep. Host: So, what other sorts of living systems are on, are on Orion. I guess, well, okay, I'll lead in the right direction for, for example, environmental, right. So to live you have to, you know, you're in space, but it's got to be a certain temperature, right? Jessica Vos: Yeah. Host: You got to have oxygen and carbon dioxide removal and stuff like that. Jessica Vos: Yeah, those humans are rather picky, right. Like we take an exact just so much of a temperature swing or a pressure swing, and we just get uncomfortable really fast. So, there's comfort and survival, right. Host: Yeah, yeah. Jessica Vos: So, Orion will be pressurized at 14.7 pounds per square inch, or PSI, which is exactly what you would see here in Houston, Texas, because we live pretty much at sea level. So that's fantastic. Host: Yeah. Jessica Vos: We don't really have to deal with any sort of feelings or impacts to performance due to changes in pressure. Host: Cool. Jessica Vos: The air is also the exact same concentration of oxygen and nitrogen and all the rest of the trace contaminants, well we should be cleaner, honestly. But, yeah, so we're looking at 21 percent oxygen and the rest nitrogen for the most part, so. Host: All right. So it's, okay, so it's emulating all of that, and all of this is in a tiny, is the environmental systems, do they have to be designed to be more compact, or was it kind of a cut and paste sort of technology? Jessica Vos: Great question. So I believe that what we are flying on Orion is a fairly new and more compact system. It is a mean swing bed, it's a solid mean swing bed technology, which we have three units, and it's designed to be, as most systems are on this spacecraft, anything that's needed in different nominal missions, and nominal mission duration for four crew for 21 days, we try to design redundancy into, so that if something happens and you're just not quite sure what it was, okay, you know what, we're going to switch to this other thing instead, or we're just going to use the second one that we, you know, built into the system. So that's how the ECLS system is. We have three units, and each unit has two beds that swing. So, what the purpose of the solid mean is to basically remove the CO2 from the air. There's other kinds of filters within that system that'll take out other types of contaminants, but the main thing that we really worry about from a human health perspective and human performance perspective is that CO2. So, it'll take out the CO2. It basically attaches, the solid mean is really sticky. It likes the CO2, and then when we flip the bed and expose it to vacuum, all of it goes away. Host: Wow. Jessica Vos: Yeah, so once the bed is full, you turn around and expose it to vacuum, I think it's like 20 minutes or something max, and then you flip it around again, and we have three different units that do that same process. Host: All right. Jessica Vos: Yeah. Host: All right. So, pretty efficient then, I would guess, right? Because you're right, you built in the redundancy. Jessica Vos: Yep. Host: And talking with Nujoud before, that redundancy is built like, all right, we can have this amount, but if we go, if we do, you know, more redundant systems, then that's more weight, so what's the right amount, and then, boom, you locked in on the three, you said, right. Jessica Vos: Yep. Host: Yeah, very cool. Jessica Vos: Yep, and like every single system has to have that trade of how much tolerance you're going to build into it. Some systems we just say, you know what, we're going to have to, we can't afford it, we're going to have to fly in terms of mass. We don't have the spare mass for this one versus this other more important one that we need the mass for, so we are going to decide to control it via operational controls in flight instead. Just make sure that we only operate it for this much time or we only use it for this much, and you can, you know, there are, those are some of the other ways that you can manage the resources and the consumables that you don't have extra of, right. Host: Yeah. Jessica Vos: Power is like that quite a bit. It's the same way on the space station right now. Host: Yeah. Jessica Vos: Like you have to know exactly what you're plugging into and how long you're plugging into it because you could short something else out over here, you know, so. Host: So, I'm guessing Orion has power constraints too, right. Jessica Vos: Yeah. Host: Is it going to be solar powered? Jessica Vos: Yes. Host: Okay. Very cool. So how is the solar panels now. Because I've seen various pictures in the past of, you know, you got the ones that are more circular and ones that are more like an X. Jessica Vos: We're the X. Host: We're the X now. Jessica Vos: Yeah. Host: Cool, I like that one. Jessica Vos: Yeah, yeah, we are the X. We've got four. Host: Sweet. Jessica Vos: You know, that kind of do the pretty unfolding thing. Host: All right. Jessica Vos: So, yeah, but they go, they extend out fairly long, I don't know the exact numbers, but yeah. Host: Okay, and that will, it'll be solar powered and-- Jessica Vos: Um-hum. Host: Okay, very cool. So another big one that I know about is, and you were talking about all of the important stuff being around, the waste management, right. Jessica Vos: Um-hum. Host: Right. So you're going to be on there in the one room with four people for quite some time. Jessica Vos: Yep. Host: So how is the bathroom situation? Jessica Vos: Tiny. It is a very tiny, like smaller than a telephone booth like closet thing. Host: All right. Jessica Vos: It is very tiny, and it's really funny too because I believe as it's oriented right now, just because you only have so much room in the spacecraft, right, I think the exercise device sits right above the door for the WM. Host: No. Jessica Vos: So you may have to interrupt somebody's exercise session to go in and then, you know, interrupt it again to get out, so you know. But, you know, that's what it's like when you're camping and living in a camper. That's how things go. So-- Host: It's true. Jessica Vos: But, yeah, the design of the actual system itself, of the potty itself, is similar in, you know, concept to what we use on station today. Host: Okay. Jessica Vos: It's basically purposely driven airflow that's being intentionally directed in a certain way, you know, to help stuff get out and not get all over the place. Host: Also very important. Jessica Vos: Yes. And then it gets contained into a canister that's got some odor control features to it, and then once that canister gets full, it can be sealed and closed off and then you stick a brand-new one in, and so-- Host: All right. Jessica Vos: It's kind of a fancy bucket with a hose on the end of it and some odor-control features. Host: Hey, that's going to come in handy, because that's right next to the exercise [inaudible]. Jessica Vos: Yes, I know. Host: That whole area, I know I would hang out on the other side if I was at Orion for the most part for sure. Jessica Vos: But, yeah, in general I'm not sure that there's a whole lot of privacy going to be offered on this vehicle. I mean, of course there's always the option of hanging up your sleeping bag. I mean you had a question about that, and it's really more of just a blanket with Velcro straps on it that allow you to adjust the squeezability, right, how tight it is on your body, and then some D-rings to adhere it to some pieces of structure so that you don't go floating off into each other when you're sleeping. But there is the option of hanging that up, you know, putting the D-ring up, or getting it unfolded and sticking out so that you want to be behind it. But I'm just, I can't imagine that with 21 days of taking that much time and energy to make sure that you get, you know, behind your little curtain, I don't know. Host: Well, you know what, I would assume with a crew of four astronauts that are going on these missions, I would assume that they are going to be a very tight-knit group of people. Jessica Vos: Yeah. Host: And just talking with space stations astronauts and even HERA, just talking with them too, whenever you're with people in these environments, you learn to, you know, teamwork is very important. Camaraderie is very important, and all of that sort of translates into if you're going to the bathroom, respect each other, so-- Jessica Vos: Yeah. Absolutely. Host: Yeah. Just out of curiosity, I’m thinking about the movie Apollo 13. So when they were on that trip, they didn’t have the water recycling system that we have on the International Space Station, they literally ejected it out into space. And it had this sort of cool crystal effect as it was floating away. Is that what’s going to happen on Orion? Jessica Vos: It absolutely is. Host: Ah that is so cool. Jessica Vos: Yeah, I’m not sure that they’re going to be able to see it the same way. You know, just based on where the windows are and where that ejection port it, but – or the evacuation port I guess – but that’s how we’re going to do it. Host: Ah, okay. I hope they get some good views – this kind of sounds weird to say – but it is kind of cool to see the crystallization of pee. Jessica Vos: Yeah, so I’ve heard! Host: Very cool. There's a, you know, one thing I was thinking about actually is, we just moved right from flying the thing and like how, where everyone's going to be sitting to just kind of living, but I know there's going to be a launch and entry suit that you have to wear at first, right. So these bulky like orange suits, right. It's kind of like the, it's an upgraded, new, fancy pumpkin suit, right. Jessica Vos: Right. Host: Kind of. So once you're wearing that and now you're in orbit and now you're transitioning to living on Orion, where does that pumpkin suit go? Jessica Vos: So it has, it has another locker. Host: A locker, okay, cool. Jessica Vos: Yeah, just another locker, but that suit becomes really important in some of the, on orbit, in the event that some emergency happens like a depressed cabin, so if something happens that causes your cabin to depress for any reason, all of the systems in there including the food system and everything are meant to be, to provide for 144 hours of depressurized cabin survival. Host: Oh, okay. Jessica Vos: So 144 hours, basically six days. Host: Yeah. Jessica Vos: That's kind of like, yeah, worst case you're on the far side of the moon and something happens, your cabin depresses, and you have six days until you can get home. Host: From the far side of the moon though, how long until you get home? Jessica Vos: Six days. Host: Oh, okay. So it's literally planned for exactly that, in worst case scenario. Jessica Vos: It's meant to cover that worst case scenario, absolutely. Host: Got it, okay. Jessica Vos: So, in that event, you're getting in your suit, and you're living in your suit. So that suit also has some unique features to it that the pumpkin suits from the space shuttle program did not have. Host: Oh, okay. Jessica Vos: That would allow for, you know, the collection and mitigation of human waste. Host: Wow. Jessica Vos: Yeah, because that's six days' worth of living, right. Host: Um-hum, yep. It's also going to allow you to take in some calories and some water. Host: Okay. Jessica Vos: So there's special food bags and food-like consistent, what am I trying to say, like material, like it's going to be, and you wouldn't normal eat it, but if you had to, it's going to be like this, I don't want to say sludge, but it's kind of like a, it's like a powdery mixture that you would-- Host: It's not like the running gel, right? Is it kind of like that? Jessica Vos: It would be kind of like that. Host: Okay. Jessica Vos: Yeah, that would allow you to take in a lot of calories. Host: Yeah, that's what those are for, right. Jessica Vos: In a pouch, right. Host: Yeah, yeah. Jessica Vos: But it's specific to interfacing with the spacesuit and being operated with gloved hands and with a vacuum on the outside environment, right. So it's a pretty tricky thing to-- Host: Is it like a straw that goes through the helmet or something and then you squeeze it through? Jessica Vos: Basically that's what you would see. Host: Oh, okay, yeah. Jessica Vos: Yes, yeah. Host: Oh, yeah, that's how I'm imagining. I'm sure it's more complicated. Jessica Vos: Right, right. So there's a whole team of engineers that is working on putting that system together to make sure that the crew won't be starving for that 144 hours that they will. But you can't pop the visor, you can't, you know, the whole, the whole interior of the spacecraft at that point is a vacuum. Host: Right. Jessica Vos: So-- Host: So you have to survive in the suit, and that suit has to support you for six days. Jessica Vos: Yep. Host: Whoa. Jessica Vos: Yeah. Host: That's cool. I actually think, is it, is it Cody Kelly? Jessica Vos: Yeah. Host: Jessica Vos: Is that the guy? Jessica Vos: Yeah. Host: Okay, yeah, I got his name about crew survival and stuff, so we're really going to have to bring him on the podcast. Jessica Vos: Oh, absolutely. That would be a-- he's a fun person, and he does all the fun stuff so-- Host: Awesome. That would be cool. Yeah, so the suits themselves are designed, but then, you know, they go into a tiny little locker, and then, you know, hands off for that. Jessica Vos: In fact, the seats do as well. Host: Oh, the seats go in lockers? Jessica Vos: Yeah. The whole cabin configuration just kind of changes from okay we're in flight mode to now were in just coast mode, right. Host: Whoa. Jessica Vos: And just live and do science experiments. Host: Do the screens stay? Jessica Vos: Yes. Host: The screens stay, the chairs go, the suits go, and it opens up this whole thing. Jessica Vos: Yep. Host: Oh, that's so cool. You know what, I did skip over, because you did briefly mention it, and then I just sort of skipped over it, but beds, you know, like sleeping. It sounds like it's just going to be a sleeping bag strapped to a wall. Jessica Vos: Right, yeah. I was going to say, not so much with the bed. There's no mattress, no, but there's also no gravity, so it's kind of cool, and this is, it's very similar to on space station. Host: Right. Jessica Vos: They find themselves rather comfortable once, you know, they adjust, that whole, you know, the way you feel when you first enter microgravity and the first couple of days can be a little, a little strange on the body. Host: Yeah. Jessica Vos: But you do get used to it fairly quickly. It only takes a couple of days, but once you're there, it's really comfortable, and what they do is they have a blanket. It's just thin though. It's not like a big poufy sleeping bag or anything like that. It's just thin because the temperature inside the cabin is, you know, that very comfortable kind of 72 to 75 degrees, and it's got various straps in places so that where you want to feel that snuggy feeling, right, you can, do it tight, but for the most part, they actually like to just kind of leave it a little bit loose, and you'll see them, they kind of sleep like zombies. Host: Right. Jessica Vos: Like they have their arms out in front of them, and they're just kind of hanging and they're floating, and it's funny because the station sleeping, quote unquote, sleeping bags are, they've got all of these straps and this and that to make sure your head doesn't go bobbling around and so you can hook yourself to the wall and you can get it super tight if you want. And it just seems like none of that gets used. Just floating there feels nice. Host: Yeah. Jessica Vos: You know, you can imagine, if you just kind of let your body just float in a pool. Host: Oh, yeah, that's a good feeling, that's a good feeling. Jessica Vos: You know, yeah. So they're just like, all right, I'm going to sleep now. Just lean back and let their arms float and-- Host: Yeah. Jessica Vos: You know, but they do, they do, I think, at least give themselves a little bit of a restraint so that they know they're not going to end up in somebody else's space overnight or into a different module entirely. Host: That's true. You don't want to play like space bumper cars in the middle of the night, just kind of slamming into each other. That would be weird. Yeah, just from talking to a couple astronauts, they both said, sleeping, you know, once you get used to it, sleeping in space is probably the best sleep you'll ever get. Because, if you think about it, right, even in a bed here on Earth, you still have gravity pushing you against that bed. In space you have-- Jessica Vos: And it's pushing that weight of the blanket on you too, which is so comforting. Host: Oh, that is, that is comforting, yeah. But just nothing pressing on you, that's got to be a fantastic feeling. Jessica Vos: Yeah. Host: I bet you it should. Jessica Vos: Yeah. Host: Just out of curiosity, for the way the mission is designed, for Orion missions, would it be kind of lights out, crew go to sleep, all at the same time, or are they going to be shifting? Jessica Vos: As far as I understand it, there's not going to be much shifting. They're going to be on a very similar, in terms of a day night schedule and sleep schedule, it'll be fairly similar. What they will shift is their exercise sessions and their kind of personal time sessions, but from a day-night cycle, it would be the same. Host: Okay. Do they have the ability to sort of switch to like night mode and maybe turn the lights off or change them to like a warmer color? Jessica Vos: Well, so that's interesting you ask that, because lighting is a big deal in terms of, you know, the habitability of an environment, right. Host: Definitely. Jessica Vos: You can have some really harsh lighting and just get headaches all the time, and you'd just be really like, grrr, and it's due to the lighting. So I believe that the systems, there are requirements now for how we design habitable environments and what kind of lighting is required, and I know that they've implemented some interesting new blue light stuff up on space station. So, I believe that that is one of the, going to be one of the capabilities with the lighting system in Orion, is to have different basically modes of light. I don't know how fancy they're going to get, because it's not light we've got the Lexus of space crafts here, you know. But that is something that is, in terms of helping them stick to a cycle, a day-night cycle, the whole circadian rhythms and all of that stuff, all of that science has been done, we know it works. And so I believe that part of, at least some of that is going to be implemented in the lighting system in Orion. Host: Yeah. Because I know they are doing, it's called the lighting effect study on station, and it's exactly that. LED lights, change them to a little warmer things in your crew quarters or something, so at night you don't have this big fluorescent light in your [inaudible]. Jessica Vos: Absolutely, yeah, they use them in HERA too. Host: Oh, oh yeah they do. That's right. Jessica Vos: The whole bottom floor of the lab has a completely different set of lights than the habitation floors, both with the galley and the exercise equipment and stuff and then the sleeping tents, you know, on the very top floor of HERA, so-- Host: Yeah, just actually learning some of this stuff from HERA from this light effect study, I actually put like a blue light filter on my phone and on my computer like so at night I can, you know, I can browse a little bit without having to worry about it actually affecting my sleep. Jessica Vos: Yep. Host: Which after learning about it, I realized, oh my gosh, that's why I'm not sleeping, because I'm screens before bed. You can't do it. Jessica Vos: So in terms of speaking of screens, they will have laptops. Host: Cool. Jessica Vos: Anywhere between two and four. There might be a couple laptops and a couple of iPads. All of that is still to be determined, but it is currently accounted for in terms of the mass allotment for that kind of a system. Host: All right. Jessica Vos: And there's some dependencies there and some reasons why we would use that stuff. One is to get rid of a bunch of paper, right. You can do all of your procedures and stuff from your tablet. They do that on station all the time now. And another, especially from the crew health perspective is that that's how they would be able to do any sort of video conferencing, right, with home. So I say that, at the same time, the way that EM2, the EM2 vehicle is currently equipped, it's only got the S band communication technology. Host: So only radio, no visual. Jessica Vos: Pretty much. You might be able to squeeze a little bit in there, pictures but probably not real-time skype-like video. Host: Yeah, yeah. Jessica Vos: So, but there is some potential to expand Orion's capability with optical communication, and once they would do that, then for sure they'd be using these laptops to do more, you know, videoing with their families at home. But they absolutely will have time each day or at least every other day or something along those lines to be communicating with their families. Host: Nice. All right. So that's part of their day, right. Actually that's a good conversation to have is we know that they are, you know, they're going to be working out. We know that they're going to be sleeping. What's a day on Orion like on this mission. I guess, you know, talking with family, but, you know, is that built into the mission profile? Jessica Vos: So we are flying people that are very good pilots for a reason. Good pilots and good scientists, right. Okay, well I guess it's pilots, scientists, and engineers. Host: All right. Jessica Vos: And the reason for that is because you need people, this EM2 mission is a mission that has not been done before. Similar things have been done in Apollo, but that spacecraft was different, and the designs and how we got the mission done was a little bit different. So this EM2 mission is really a checkout mission, and there's a lot of dynamic phases of flight. A lot of, you know, translunar injection burns and stuff going on. We're co-manifesting a payload on this mission, so there is a lot to, and it's just the first time that all of this stuff is going to be used in the manner that it was meant to be used by humans, right. EM1 will test out a lot of the structure and the systems that are just automated and controlled from the ground, so that's good, but this is when the humans will kind of, you know, be doing the ringing out of all the different things that may or may not have been known about how this design is going to work. Host: Yeah, yeah. Jessica Vos: So they're going to be doing a lot of, you know, checking out, a lot of system checkout and kind of on purpose, you know, kind of driving certain systems to do certain things. They're going to be piloting and navigating that spacecraft through all the different dynamic phases of flight. They are going to be, there probably will be some science, but I don't expect that to come until like a little bit later missions, once we've really kind of flushed out what the system can handle and what it can't, because they need to be ready just in case something just isn't working the way it was planned to, designed to for whatever reason. Host: Right. Jessica Vos: They will spend a little bit of time doing their meal prep and meal time, and for the most part, that's kind of the only planned relaxation time, right. They do have their personal time of personal hygiene, which usually is right after the exercise, right, but as a crew and being able to just relax, sit back, and, you know, I wouldn't say drink your coffee, but squeeze your coffee because it's in the same kind of like, it's like a Capri Sun for coffee, the same kind of thing, with a special straw in it that keeps it from leaking out when you're not actually sucking on it. And so from that standpoint, there is meal prep time. The food comes in lots of different kinds of packages that take different kinds of preparation, whether that's just heating or putting water in and letting it sit out and that kind of thing. So they'll prep the food. They'll prepare their coffee, and then they'll sit back and eat, and they'll do that two, three times a day. So, yeah, I think that's pretty much the extent of what they're going to be doing on EM2. And then once we start getting, hopefully we'll understand how these systems behave and how much maintenance they all really require and be able to move into doing more science, even on the shorter Orion missions and then extend that into what the deep space gateway would have with their habitation module and their labs and stuff. Host: All right. I can think of like a lot of different podcast episodes just on all of this, right. Like we could probably do one just on EM2 so people understand what that's all about. We could probably do one just on some concepts for deep space gateway. Like there's a lot of like, because I can definitely ask a lot of questions, but we will be here for hours. Jessica Vos: No, let's not do that. Host: Yeah, yeah. Jessica Vos: It's freezing in here. [laughter] Host: I'm so sorry. I should have said to bring a jacket. We did talk briefly with Nujoud about EM1 and just the structure of that mission real brief, right. Another thing we need to do is actually cover EM1 through and through, but that's going to be no crew. It's going to be going translunar injection, way out past the moon, coming back super-fast to test the heat shields. And you're right, a lot of it is structural and just understanding about the space craft. Jessica Vos: Yep. Host: Do you think you can give like a two-minute explanation of EM2, or is that really something we should probably save for a podcast. Jessica Vos: Well, for the two-minute explanation, we will be launching from Kennedy Space Center on top of the SLS, and there will be a comanifested payload along with this mission. So not only is it the first manned mission of Orion, but we will also be bringing [inaudible] payload along with us. And the AA2, I was trying to think about the launch abort, so there will be the LAS system on top of the Orion, so in terms of the rocket sack that you'll see, you'll see SLS. You will see Orion, but Orion will be covered by the LAS shroud, the Launch Abort Systems shroud. But the test of that system is actually coming up before EM1, so that will be really exciting to see. Host: Yeah. Jessica Vos: So, once we, after we launch and we get rid of the LAS, because we didn't need it, thank goodness, right, everybody was cool, we will be going around the orbit one time in kind of a low Earth orbit, and then we'll continue on into a high Earth orbit, at which point we'll kind of separate from the first stage and let that go, and the comanifested payload in Orion will go in different directions, both going to the moon, but in different orbit trajectories, orbital trajectories. Host: Ah, okay. Jessica Vos: So there will be two different stages of the rocket taking these two things in two different directions, and they'll do two different translunar injections, but at that point in the mission, the Orion and the service module are heading out to the moon as are the comanifested payload, or as is the comanifested payload. When it is on a trajectory that's going to take several, several days to get into a different orbit, it's going to be a near rectilinear halo orbit that the comanifested payload will be going into, and we will be going into just a free return trajectory around the moon. Host: Okay, all right. And then-- Jessica Vos: And that is expected, from the Orion perspective, it takes about, yeah, about 10 to 12 days to do that mission. Host: Okay, 10 to 12, and that's when we're getting to the Orion can last for 21 days, but this is more of a 10 to 12 sort of deal. Jessica Vos: Yeah. Host: Okay. So the comanifested payload, that stays there, right. It doesn't come back? Jessica Vos: It does not come back. Host: But the people definitely do, right. Jessica Vos: Yes, exactly. Host: Yeah, cool. Jessica Vos: But, yeah, the comanifested payload will be staying in that NRHO orbit around the moon, kind of that polar orbit, it looks that way. Host: Yeah, uh-huh. Jessica Vos: And, yeah, but we'll be coming, we'll be coming back. Host: Cool. All right. Jessica Vos: So there's a whole suite of landing and recovery systems as well that allow us to retrieve the capsule once it lands and allows us to survive re-entry and then get to the capsule and recover it. Host: Yeah, so landing and recovery, is that like a, what's included in that package? Is that parachutes or am I-- Jessica Vos: Yeah, yeah. Like everything that we need on that heat shield, the parachutes. There's a system called the command module uprighting system that is, or the crew module uprighting system, excuse me, not the Apollo. It is what will make sure that we are able to upright the vehicle should it land with its, you know, docking hatch side down in the water. We don't want it, that's not the proper orientation, right, that would have the crew hanging in a funny position in their seats, so we want it to flip back over on it's own. So those come out and inflate. Those are those big orange, you know, balloon things that you see on the top of the capsule. Host: Oh. Jessica Vos: They used them in EFT1's. Host: Yes, yes. I know what you're talking about. They're just, they look like big puffy life jackets sort of, I guess. Yeah, cool. Jessica Vos: And there's a series of parachutes that go to that. I think there's 11 total parachutes, when you think about all the droves and then the main, so, yeah that's a whole system in and of itself, just like the abort system protects you from anything that might go wrong on the pad. Host: Yeah. Jessica Vos: And then we also have a service module abort capability, which is, should anything go wrong, when you made it to orbit but now something happened that you're not able to complete the entire mission, but you don't have to lose the crew, you can just abort to an Earth orbit and then come back in, you know, intentionally, from that orbit instead of having gone all the way out to the moon and back. Host: Ah. Jessica Vos: So lots of orbit capability. A lot of capability for keeping the crew alive. In fact, you've got that launch abort capability. You've got the system, sorry, service module abort capability. You've got the 144-hour survival scenario. Host: Right. Jessica Vos: So when the crew is in their suits. Host: Yes. Jessica Vos: And then you also have, should you land just something off nominal, the cabin is required to provide the crew with a habitable environment for up to 24 hours. So that would be a not very fun 24 hours. I can tell you right now. It's going to be, you're going to feel thick just from having gone through what you went through, let alone bobbing and rocking on the ocean. Depending on where you landed, that might be kind of a warm cabin, not a whole lot of cooling available for that time. There is ventilation. You open up what's called a snorkel fan, and you will get airflow, but, yeah, it's going to be, but the point is, is that they're not going to, they will be able to stay alive and be kept safe on the ocean for up to 24 hours. Host: All right. A lot of things to think about for a worst case scenario, but it seems like you got it, you got it like covered all along the way. You got launch abort, you have crew survival within the suits, you got this whole waving in the ocean but still able to, you know, figure it out, even if the capsule lands upside-down, flipping it up like right side up, so. Jessica Vos: Yeah, that is basically what human spaceflight is all about. In order to bring back, you know, that experience that they have and to be able to use that knowledge and expertise during the mission, you got to keep them alive, and you got to keep them performing well. Host: Yeah. Jessica Vos: So, all of that goes into, you know, making sure that we, those are national assets at that point, right. All of our astronauts that go and get all this knowledge. Host: The human and the human space flight is definitely the most important [inaudible]. For sure. Awesome. Well, Jessica, thank you so much for coming on the podcast. That was an awesome description of, I felt like I was there. I felt like I was living in Orion. I felt like I was slurping on those things through the suit. I didn't want to, but I felt it. But, yeah, no, that was really, that was really awesome. We're definitely, and I thought of so many different more podcast episodes that we can do, just covering all of these different things, because this was just like a high level like, you know, even just, you know, going through the intricate details of living on Orion, there's still so much more to talk about, so definitely looking forward to another podcast. Thanks so much for coming on. Maybe one more time, we'll probably have to have you another time. Jessica Vos: All right, thank you so much. Host: Yeah, cool. [ Music ] Host: Hey, thanks for sticking around. So today we talked with Jessica Vos about living in Orion and kind of the space of how it's all laid out, and there's a lot more that we could have talked about with Orion as I mentioned at the end of the podcast. If you want to know more right now and just can't wait for another episode of Houston We Have a Podcast, go to NASA.gov/Orion. I would say there's definitely some cool stuff to come in Houston We Have a Podcast, but if you want to know right now, just go to that website. Or on Facebook, Twitter, and Instagram, it's @NASAOrion, that's on Facebook. Twitter is @NASA_Orion, and then on Instagram @exploreNASA is like Orion and space launch system all of that kind of combined. If you have a question specifically about Orion, use the hashtag askNASA on any one of those platforms, and ask that question there, or you can submit and idea to the podcast. Just make sure to mention it's for Houston We Have a Podcast. This podcast was recorded on November 16, 2017. Thanks to Alex Perryman, Rachel Kraft, and Laura Rochon. And thanks again to Ms. Jessica Vos for coming on the show. We'll be back next week.