Lateral impact injuries with side airbag deployments—A descriptive study

PubMed Central

Yoganandan, Narayan; Pintar, Frank A.; Zhang, Jiangyue; Gennarelli, Thomas A.

2006-01-01

The present study was designed to provide descriptive data on side impact injuries in vehicles equipped with side airbags using the United States National Automotive Sampling System (NASS). The database was queried with the constraint that all vehicles must adhere to the Federal Motor Vehicle Safety Standards FMVSS 214, injured occupants be in the front outboard seats with no rollovers or ejections, and side impacts airbags be deployed in lateral crashes. Out of the 7812 crashes in the 1997–2004 weighted NASS files, AIS ≥ 2 level injuries occurred to 5071 occupants. There were 3828 cases of torso-only airbags, 955 cases of torso–head bag combination, and 288 inflatable tubular structure/curtain systems. Side airbags were not attributed to be the cause of head or chest injury to any occupant at this level of severity. The predominance of torso-only airbags followed by torso–head airbag combination reflected vehicle model years and changing technology. Head and chest injuries were coupled for the vast majority of occupants with injuries to more than one body region. Comparing literature data for side impacts without side airbag deployments, the presence of a side airbag decreased AIS = 2 head, chest, and extremity injuries when examining raw data incidence rates. Although this is the first study to adopt strict inclusion–exclusion criteria for side crashes with side airbag deployments, future studies are needed to assess side airbag efficacy using datasets such as matched-pair occupants in side impacts. PMID:16911812

Reducing risks to children in vehicles with passenger airbags.

PubMed

Graham, J D; Goldie, S J; Segui-Gomez, M; Thompson, K M; Nelson, T; Glass, R; Simpson, A; Woerner, L G

1998-07-01

This review examines the risk that passenger airbags pose for children and discusses behavioral and technologic measures aimed at protecting children from airbag deployment. Although airbags reduce fatal crash injuries among adult drivers and passengers, this safety technology increases mortality risk among children younger than age 12. The magnitude of the risk is multiplied when children are unrestrained or restrained improperly. As new vehicles are resold to buyers who tend to be less safety-conscious than new car owners, the number of children endangered by passenger airbag deployment may increase. For vehicles already in the fleet, strong measures are required to secure children in the rear seat and increase the proper use of appropriate restraint systems through police enforcement of laws. One promising strategy is to amend child passenger safety laws to require that parents secure children in the rear seats. For future vehicles, a mandatory performance standard should be adopted that suppresses airbag deployment automatically if a child is located in the front passenger seat. Other promising improvements in airbag design also are discussed. Major changes in passenger airbag design must be evaluated in a broad analytical framework that considers the welfare of adults as well as children.

A Case of Severe Airbag Related Ocular Alkali Injury

PubMed Central

Wong, William; Affeldt, John C

2012-01-01

While airbags have saved many lives and are clearly beneficial overall, sodium hydroxide (NaOH) powder produced by the inflation reaction can cause significant alkali ocular injury if not irrigated promptly. Here we report a case of severe airbag related ocular alkali injury as a way to bring attention to the need for prompt ocular irrigation following motor vehicle accidents (MVA) with airbag deployment. A 47-year-old man was involved in a MVA with airbag deployment in a rural setting. Attention was paid to several other life-threatening traumatic injuries, however, ocular irrigation was not performed until some 6–7 hours after the MVA. Over the course of 6 months, airbag related alkali injury caused severe limbal ischemia, conjunctivalization of the cornea, corneal epithelial defects, cicatricial scarring, haze, and corneal/limbal vascularization despite amniotic membrane graft. Awareness of the importance of ocular irrigation following airbag deployment must be raised both in the ophthalmology and emergency medicine communities. PMID:22900239

Protection against impact with the ground using wearable airbags.

PubMed

Fukaya, Kiyoshi; Uchida, Mitsuya

2008-01-01

Incidental falls from heights, falls on the same level caused by slipping or tripping, and falls from wheelchair overturns are commonplace phenomena, associated with serious injuries from impact with the ground. A wearable airbag device is a countermeasure applicable to all these types of incidents. Three types of wearable airbag systems were developed and evaluated: for protection against falls from heights (Type-1), against wheelchair overturns (Type-2), and against falls on the same level (Type-3). The systems consist of an airbag, sensor, inflator, and jacket. The sensor detects the fall and the airbag inflates to protect the user. Fall tests using dummies with/without the airbags demonstrated the effectiveness of these devices. In the experiments with system Type-1, for fall heights of less than 2m, the airbags reduced the impact acceleration, and the Head Injury Criterion (HIC) values were under 1,000, the auto-crash test requirement. However, there are limits to the amount of protection afforded: in Type-1, the airbag can protect only the back of the head.; in Types-2 and 3, the fall height of the center of gravity is lower than 2m, and there is some margin of extra protective resource, which can be used to extend the protected area.

Airbag induced corneal ectasia.

PubMed

Mearza, Ali A; Koufaki, Fedra N; Aslanides, Ioannis M

2008-02-01

To report a case of airbag induced corneal ectasia. Case report. A patient 3 years post-LASIK developed bilateral corneal ectasia worse in the right eye following airbag deployment in a road traffic accident. At last follow up, best corrected vision was 20/40 with -4.00/-4.00 x 25 in the right eye and 20/25 with -1.25/-0.50 x 135 in the left eye. This is a rare presentation of trauma induced ectasia in a patient post-LASIK. It is possible that reduction in biomechanical integrity of the cornea from prior refractive surgery contributed to this presentation.

Lifting and protecting residential structures from subsidence damage using airbags

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

Triplett, T.L.; Bennett, R.M.

1998-12-31

Conventional practice in protecting residential structures from subsidence damage concentrates on saving the superstructure. The foundation is sacrificed, even though it represents the structural component with the greatest replacement cost. In this study, airbags were used to lift a 20 ft x 30 ft structure to test their ability to protect both the foundation and superstructure from ground settlement. Two contiguous sides of the test foundation were unreinforced, and the other two contiguous sides incorporated footing and wall reinforcement. The airbags successfully lifted the structure without causing damage, even on the unreinforced sides. This paper gives a procedure for determiningmore » airbag spacing, and describes installation and operation techniques of the airbags. The paper then focuses on the performance of the airbags in lifting the structure, and shows that airbags can preserve existing foundations during subsidence movements.« less

Are airbags effective in decreasing trauma in auto accidents?

PubMed

Williams, Regan F; Croce, Martin A

2009-01-01

Multiple studies have addressed the effect of airbags on injury and mortality after motor vehicle collision with discrepant results (Table 1). Although large, population-based studies have minimized the protective effect of airbags, the most recent studies examining airbags have shown a decrease in injury and death, with the greatest protective effect seen when they are used in conjunction with seatbelts. Optimal restraint use is also associated with a decrease in infectious morbidity and hospital resource utilization. The widespread use of seatbelts and airbags will continue to save lives and decrease morbidity after motor vehicle collision.

Airbags and Sojourner Rover

NASA Image and Video Library

1997-07-05

This image from the Imager for Mars Pathfinder (IMP) camera shows the rear part of the Sojourner rover, the rolled-up rear ramp, and portions of the partially deflated airbags. The Alpha Proton X-ray Spectrometer instrument is protruding from the rear (right side) of the rover. The airbags behind the rover are presently blocking the ramp from being safely unfurled. The ramps are a pair of deployable metal reels that will provide a track for the rover as it slowly rolls off the lander, and onto the surface of Mars, once Pathfinder scientists determine it is safe to do so. http://photojournal.jpl.nasa.gov/catalog/PIA00614

FRP : Strengthened RC Structures

NASA Astrophysics Data System (ADS)

Teng, J. G.; Chen, J. F.; Smith, S. T.; Lam, L.

2002-01-01

The strengthening of reinforced concrete (RC) structures using advanced fibre-reinforced polymer (FRP) composites, and in particular the behaviour of FRP-strengthened RC structures is a topic which has become very popular in recent years. This popularity has arisen due to the need to maintain and upgrade essential infrastructure in all parts of the world, combined with the well-known advantages of FRP composites, such as good corrosion resistance and ease for site handling due to their light weight. The continuous reduction in the material cost of FRP composites has also contributed to their popularity. While a great amount of research now exists in the published literature on this topic, it is scattered in various journals and conference proceedings. This book therefore provides the first ever comprehensive, state-of-the-art summary of the existing research on FRP strengthening of RC structures, with the emphasis being on structural behaviour and strength models. The main topics covered include: Bond behaviour Flexural and shear strengthening of beams Column strengthening Flexural strengthening of slabs. For each area, the methods of strengthening are discussed, followed by a description of behaviour and failure modes and then the presentation of rational design recommendations, for direct use in practical design of FRP strengthening measures. Researchers, practicing engineers, code writers and postgraduate students in structural engineering and construction materials, as well as consulting firms, government departments, professional bodies, contracting firms and FRP material suppliers will find this an invaluable resource.

The effects of depowered airbags on skin injuries in frontal automobile crashes.

PubMed

Rath, Amber L; Jernigan, M Virginia; Stitzel, Joel D; Duma, Stefan M

2005-02-01

The purpose of this study was to determine the effects of depowered frontal airbags on the incidence of skin injuries. The National Automotive Sampling System database files from 1993 to 2000 were examined in a study including 2,246,524 occupants exposed to airbag deployment in the United States. There was no significant difference between full-powered and depowered airbags, with 60.2 percent of those exposed to a full-powered deployment sustaining a skin injury versus 59.5 percent of occupants exposed to a depowered airbag (p = 0.19). Whether occupants were exposed to a full-powered airbag (1,936,485 occupants) or a depowered airbay (310,039 occupants), the majority of skin injuries were to the upper extremity and the face. Regardless of airbag power, the overwhelming majority of the skin injuries were minor (99.8 percent). There was not a significantly greater risk of injury from any source for occupants exposed to a depowered airbag or a full-powered airbag (p = 0.87). The data suggest that the implementation of depowered airbags did not affect the number, seriousness, location, or source of skin injuries.

Examination of the impact of airbags on renal injury using a national database.

PubMed

Smith, Thomas G; Wessells, Hunter B; Mack, Chris D; Kaufman, Robert; Bulger, Eileen M; Voelzke, Bryan B

2010-09-01

Little is known about preventative measures to lessen solid organ injury in motor vehicle collisions (MVCs). To evaluate the efficacy of airbags in reducing renal injuries in MVC, we analyzed renal injury rates in vehicles with and without airbags using the Crash Injury Research and Engineering Network (CIREN) database. The CIREN database was queried for MVC and renal injury from 1996 to September 2008. CIREN is weighted toward late model vehicles and selects more severely injured patients. Search fields were primary direction of force (PDOF), presence of airbags, and location of airbags (steering wheel, instrument panel, seat back, door panel, and roof-side curtain). Abdominal Abbreviated Injury Score was converted to AAST renal injury grade. Renal injury rates were compared between vehicles with and without frontal and side airbags. We reviewed 2,864 records and identified 139 renal injuries (28.9% AAST grade III to V). In MVCs with renal injuries, frontal impact was 54.7% of total (n = 76) and side impact was 45.3% of total (n = 63). Most occupants in frontal impact MVCs had exposure to a steering wheel airbag (74.9%); 16.6% had an instrument panel (passenger) airbags. In side impact MVCs, 32.2% of occupants had a side airbag. Compared with the non-airbags cohort, frontal airbags and side airbags were associated with a 45.3% and 52.8% reduction in renal injury, respectively. Passengers in automobiles with frontal and side airbags have a reduced rate of renal injury compared with those without airbags. Our data support further study of the role of airbags in reducing renal injury after MVC. Copyright 2010 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

[A development of FRP frame for crown and bridge resin. (2) Rigidity and adaptability of FRP frame].

PubMed

Kimura, H; Teraoka, F

1990-05-01

Retainer and pontic of FRP frame for crown and bridge resin were constructed with two different prepregs, used glass cloth and roving as reinforcement. Rigidity and adaptability of the FRP frame and bonding strength of jointing of retainer and pontic were investigated. The glass content was about 50 wt% for both kinds of prepregs. Bonding strength and modulus of FRP plate reinforced with glass roving were about 1.5 times larger than that of the FRP plate reinforced with glass cloth. Bonding strength of FRP specimen constructed by curing the prepreg put on the FRP plate was about 3 kgf/mm2. However, the bonding strength of specimen constructed by curing simultaneously the two prepregs was about 12 kgf/mm2. Though discrepancy of the FRP frame to stone cast of abutment tooth was proportional to the length of pontic, that of the FRP frame with a 50 mm pontic was less than 0.05 mm.

Airbag Retraction

NASA Image and Video Library

1997-07-05

This image shows that the Mars Pathfinder airbags have been successfully retracted, allowing safe deployment of the rover ramps. The Sojourner rover is at lower right, and rocks are visible in the background. Mars Pathfinder landed successfully on the surface of Mars today at 10:07 a.m. PDT. http://photojournal.jpl.nasa.gov/catalog/PIA00618

Airbag Retraction

NASA Image and Video Library

1997-07-05

This image shows that the Mars Pathfinder airbags have been successfully retracted, allowing safe deployment of the rover ramps. The Sojourner rover, still in its deployed position, is at center image, and rocks are visible in the background. Mars Pathfinder landed successfully on the surface of Mars today at 10:07 a.m. PDT. http://photojournal.jpl.nasa.gov/catalog/PIA00617

The Blue Ribbon Panel on Depowered and Advanced Airbags — Status Report on Airbag Performance

PubMed Central

Ferguson, Susan A.; Schneider, Lawrence; Segui-Gomez, Maria; Arbogast, Kristy; Augenstein, Jeffrey; Digges, Kennerly H.

2003-01-01

SUMMARY In February 2000, a group of highway safety organizations sent a letter to the Secretary of the U.S. Department of Transportation expressing concern about a possible return to the 30-mph rigid barrier test using unbelted dummies previously required by Federal Motor Vehicle Safety Standard (FMVSS) 208. The letter asked the National Highway Traffic Safety Administration (NHTSA) to expedite data collection of the real-world crash experience of airbag-equipped vehicles certified to the 30-mph sled test using unbelted dummies because of suggestions that depowered airbags may not provide the same level of protection, particularly to larger, unbelted occupants. For the same reason, the letter also recommended that the auto industry commit funding for additional data collection and to establish a panel of experts to evaluate the data. In response, the Alliance of Automobile Manufacturers (Alliance) committed to funding a 3-year program to be managed by an independent third party. A panel of experts consisting of representatives from the highway safety research community, the National Transportation Safety Board, academia, medical institutions, and the insurance industry was established as the Blue Ribbon Panel (BRP) for Evaluation of Depowered and Advanced Airbags and met for the first time in February 2001. The BRP also includes representatives from NHTSA and the automobile industry who participate as observers. The BRP held its first public meeting in April 2003 to provide an update of its activities and to summarize the real-world evidence on the performance of depowered airbags. This AAAM session will provide a brief summary of the public meeting. PMID:12941215

Dynamic response of a collidant impacting a low pressure airbag

NASA Astrophysics Data System (ADS)

Dreher, Peter A.

There are many uses of low pressure airbags, both military and commercial. Many of these applications have been hampered by inadequate and inaccurate modeling tools. This dissertation contains the derivation of a four degree-of-freedom system of differential equations from physical laws of mass and energy conservation, force equilibrium, and the Ideal Gas Law. Kinematic equations were derived to model a cylindrical airbag as a single control volume impacted by a parallelepiped collidant. An efficient numerical procedure was devised to solve the simplified system of equations in a manner amenable to discovering design trends. The largest public airbag experiment, both in scale and scope, was designed and built to collect data on low-pressure airbag responses, otherwise unavailable in the literature. The experimental results were compared to computational simulations to validate the simplified numerical model. Experimental response trends are presented that will aid airbag designers. The two objectives of using a low pressure airbag to demonstrate the feasibility to (1) accelerate a munition to 15 feet per second velocity from a bomb bay, and (2) decelerate humans hitting trucks below the human tolerance level of 50 G's, were both met.

Establishment and validation for the theoretical model of the vehicle airbag

NASA Astrophysics Data System (ADS)

Zhang, Junyuan; Jin, Yang; Xie, Lizhe; Chen, Chao

2015-05-01

The current design and optimization of the occupant restraint system (ORS) are based on numerous actual tests and mathematic simulations. These two methods are overly time-consuming and complex for the concept design phase of the ORS, though they're quite effective and accurate. Therefore, a fast and directive method of the design and optimization is needed in the concept design phase of the ORS. Since the airbag system is a crucial part of the ORS, in this paper, a theoretical model for the vehicle airbag is established in order to clarify the interaction between occupants and airbags, and further a fast design and optimization method of airbags in the concept design phase is made based on the proposed theoretical model. First, the theoretical expression of the simplified mechanical relationship between the airbag's design parameters and the occupant response is developed based on classical mechanics, then the momentum theorem and the ideal gas state equation are adopted to illustrate the relationship between airbag's design parameters and occupant response. By using MATLAB software, the iterative algorithm method and discrete variables are applied to the solution of the proposed theoretical model with a random input in a certain scope. And validations by MADYMO software prove the validity and accuracy of this theoretical model in two principal design parameters, the inflated gas mass and vent diameter, within a regular range. This research contributes to a deeper comprehension of the relation between occupants and airbags, further a fast design and optimization method for airbags' principal parameters in the concept design phase, and provides the range of the airbag's initial design parameters for the subsequent CAE simulations and actual tests.

Do motor vehicle airbags increase risk of ocular injuries in adults?

PubMed

Lehto, Kirsti S; Sulander, Pekka O; Tervo, Timo M T

2003-06-01

This study was undertaken to evaluate the risk of eye injury in motor vehicle accidents in which airbags deploy. An attempt was made to assess the possible associations between eye injuries and eyewear in these accidents. Retrospective observational case series and literature review with analysis. We conducted a literature review of 62 case reports and articles describing 110 adult cases of eye injury after deployment of an airbag and examined two Finnish accident cohorts. The fatal accident series (FAS; fatal injuries with one or more cars involved) included 121 individuals sitting behind an airbag that deployed (65 survivors), and the Airbag study (AB; nonfatal, relatively serious accidents) included 210 individuals (survivors). The type of eye injury, eyewear, and crash dynamics were studied in each of the reviewed case reports. The fatal accident series and AB studies were analyzed to disclose the eye injuries and use of eyewear and to estimate their possible relation to deployment of airbags. Analysis of the published reports revealed that airbag-induced eye injuries were not more frequently reported among wearers of eyeglasses than among nonwearers. However, open-eye injuries were reported three times more often among eyeglass wearers (P = 0.04), whereas all injuries from airbag chemicals occurred among nonwearers. With the exception of one orbital fracture with hyphema, all eye traumas (n = 7) in the FAS and AB cohorts were mild (eyebrow laceration, lid contusion, bruising). The risk of airbag-related eye injury was 2.5% for any eye injury and 0.4% for severe eye injury. In single accidents when seat belts were used, the risks were 2.0% and 0.5%, respectively. In the accidents from the FAS data no difference was observed in the risk for eye injury between survivors in incidents involving airbag deployment and incidents not involving airbags. This risk was not found to be greater among eyeglass wearers. Despite reported cases in the literature, we found that

Efficacy of side airbags in reducing driver deaths in driver-side car and SUV collisions.

PubMed

McCartt, Anne T; Kyrychenko, Sergey Y

2007-06-01

To estimate the efficacy of side airbags in preventing driver deaths in passenger vehicles struck on the driver side. Risk ratios for driver deaths per driver-side collision were computed for side airbag-equipped cars and SUVs, relative to vehicles without side airbags. Driver fatality ratios also were calculated for the same vehicles in front and rear impacts, and these were used to adjust the side crash risk ratios for differences in fatality risk unrelated to side airbags. Risk ratios were calculated separately for side airbags providing torso-only protection and side airbags with head protection; almost all head protecting airbags also had airbags protecting the torso. Car driver death risk in driver-side crashes was reduced by 37 percent for head protecting airbags and 26 percent for torso-only side airbags. Car driver death risk was reduced for older and younger drivers, males and females, and drivers of small and midsize cars, and when the striking vehicle was an SUV/pickup or a car/minivan. Death risk for drivers of SUVs was reduced by 52 percent with head protecting side airbags and by 30 percent with torso-only airbags. The effectiveness of side airbags could not be assessed for pickups and minivans due to the small number of these vehicles with airbags involved in crashes. Side airbags substantially reduce the risk of car and SUV driver death in driver-side collisions. Making side airbags with head protection available to drivers and right front passengers in all passenger vehicles could reduce the number of fatalities in motor vehicle crashes in the United States by about 2,000 each year.

Cervical spine injuries associated with the incorrect use of airbags in motor vehicle collisions.

PubMed

Donaldson, William F; Hanks, Stephen E; Nassr, Ahmad; Vogt, Molly T; Lee, Joon Y

2008-03-15

Retrospective database review and analysis. The purpose of this study is to determine the rate of cervical spine injuries with correct and incorrect use of front driver and passenger-side airbags. Summary of Background Data. Although there are abundant literature showing reduced injury severity and fatalities from seatbelts and airbags, no recent studies have delineated the affect of incorrect use of airbags in cervical spine injuries. The database from the Pennsylvania Trauma Systems Foundation was searched for drivers and front-seat passenger injuries from 1990 to 2002. The resulting records were then grouped into those using both seatbelt and the airbag, airbag-only, seatbelt-only, and no restraints. The data were then analyzed for frequency of cervical spine fractures with or without spinal cord injury and injury severity indexes. The drivers using the airbag-only had significantly higher rate (54.1%) of cervical fractures than those using both airbag and a seatbelt (42.1%). Overall, drivers using the airbag-alone were 1.7 times more likely to suffer a cervical spine fracture than those using both protective devices. Likewise, passengers using the airbag-alone were 6.7 times more likely to suffer from a cervical spine fracture with spinal cord injury than those using both protective devices. In addition, the injury severity indexes (Glasgow coma scale, Injury Severity Score, Intensive Care Unit stays, and Total Hospital days) were significantly worse in patients who used an airbag-only. Airbag use without the concomitant use of a seatbelt is associated with a higher incidence of cervical spine fractures with or without spinal cord injuries. Airbag misuse is also associated with higher Injury Severity Score, lower Glasgow coma scale, and longer intensive care unit and total hospital stays, indicating that these patients suffer worse injury than those who use the airbag properly.

Difference in dummy responses in matched side impact tests of vehicles with and without side airbags.

PubMed

Viano, David C; Parenteau, Chantal S

2016-07-03

Insurance Institute for Highway Safety (IIHS) high-hooded side impacts were analyzed for matched vehicle tests with and without side airbags. The comparison provides a measure of the effectiveness of side airbags in reducing biomechanical responses for near-side occupants struck by trucks, SUVs, and vans at 50 km/h. The IIHS moving deformable barrier (MDB) uses a high-hooded barrier face. It weighs 1,500 kg and impacts the driver side perpendicular to the vehicle at 50 km/h. SID IIs dummies are placed in the driver and left second-row seats. They represent fifth percentile female occupants. IIHS tests were reviewed for matches with one test with a side airbag and another without it in 2003-2007 model year (MY) vehicles. Four side airbag systems were evaluated: (1) curtain and torso side airbags, (2) head and torso side airbag, (3) curtain side airbag, and (4) torso side airbag. There were 24 matched IIHS vehicle tests: 13 with and without a curtain and torso side airbags, 4 with and without a head and torso side airbag, 5 with and without a side curtain airbag, and 2 with and without a torso airbag. The head, chest, and pelvis responses were compared for each match and the average difference was determined across all matches for a type of side airbag. The average reduction in head injury criterion (HIC) was 68 ± 16% (P < .001) with curtain and torso side airbags compared to the HIC without side airbags. The average HIC was 296 with curtain and torso side airbags and 1,199 without them. The viscous response (VC) was reduced 54 ± 19% (P < .005) with curtain and torso side airbags. The combined acetabulum and ilium force (7 ± 15%) and pelvic acceleration (-2 ± 17%) were essentially similar in the matched tests. The head and torso side airbag reduced HIC by 42 ± 30% (P < .1) and VC by 32 ± 26% compared to vehicles without a side airbag. The average HIC was 397 with the side head and torso airbag compared to 729 without it. The curtain airbag and torso airbag

Tracks Seam Like Airbags

NASA Image and Video Library

2004-01-28

Bearing a striking resemblance to a cluster of paper lanterns, these inflated airbags show a pattern of seams exactly like those left in the martian soil by the Mars Exploration Rover Opportunity during landing at Meridiani Planum, Mars.

Characterization of Martian Rock Shape for MER Airbag Drop Tests

NASA Astrophysics Data System (ADS)

Dimaggio, E. N.; Schroeder, R.; Castle, N.; Golombek, M.

2002-12-01

Rock distributions for the final platforms used in airbag drop tests are currently being designed for the Mars Exploration Rovers (MER) scheduled to launch in 2003. Like Mars Pathfinder (MPF), launched in 1996, MER will use a series of airbags to cushion its landing on the surface of Mars. Previous MER airbag drop tests have shown that sharp, angular (triangular) rocks >20 cm high may be hazardous. To aid in defining the rock distributions for the final airbag tests, images from the Viking Landers 1 and 2 and MPF were used to identify rocks that are >20 cm high, and characterize them as triangular, square or round. Approximately 33% of all rocks analyzed are triangular. Of the rocks analyzed that are ~20-60 cm high, ~14% are triangular. Most of these triangular rocks are small, ~20-30 cm high. Rock distributions of previous airbag platforms were similarly classified and show a greater percentage of triangular and square rocks that are ~20-60 cm high than at the landing sites. The burial of a rock (perched, partially buried or buried) was also considered because perched rocks may pose less of a threat to the airbags than those buried because perched rocks can be dislodged and roll during impact. Approximately 19% of all rocks analyzed, and ~19% of rocks that are ~20-60 cm high, are triangular and partially buried or buried. These data suggest that the platform rock distributions appropriately represented the risks to the airbags associated with triangular rocks. A similar percentage of >20 cm high triangular rocks will be added to the drop test platforms to represent landing site rock distributions.

Analysis-test correlation of airbag impact for Mars landing

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

Salama, M.; Davis, G.; Kuo, C.P.

1994-12-31

The NASA Mars Pathfinder mission is intended to demonstrate key low cost technologies for use in future science missions to Mars. Among these technologies is the landing system. Upon entering in Martian atmosphere at about 7000 m/sec., the spacecraft will deploy a series of breaking devices (parachute and solid rockets) to slow down its speed to less than 20 m/sec. as it impacts with the Martian ground. To cushion science instruments form the landing impact, an airbag system is inflated to surround the lander approximately five seconds before impact. After multiple bounces, the lander/airbags comes to rest, the airbags aremore » deflated and retracted, and the lander opens up its petals to allow a microrover to begin exploration. Of interest here, is the final landing phase. Specifically, this paper will focus on the methodology used to simulate the nonlinear dynamics of lander/airbags landing impact, and how this simulation correlates with initial tests.« less

A personal airbag system for the Orion Crew Exploration Vehicle

NASA Astrophysics Data System (ADS)

Do, Sydney; de Weck, Olivier

2012-12-01

Airbag-based methods for crew impact attenuation have been highlighted as a potential simple, lightweight means of enabling safe land-landings for the Orion Crew Exploration Vehicle, and the next generation of ballistic shaped spacecraft. To investigate the feasibility of this concept during a nominal 7.62 m/s Orion landing, a full-scale personal airbag system 24% lighter than the Orion baseline has been developed, and subjected to 38 drop tests on land. Through this effort, the system has demonstrated the ability to maintain the risk of injury to an occupant during a 7.85 m/s, 0° impact angle land-landing to within the NASA specified limit of 0.5%. In accomplishing this, the personal airbag system concept has been proven to be feasible. Moreover, the obtained test results suggest that by implementing anti-bottoming airbags to prevent direct contact between the system and the landing surface, the system performance during landings with 0° impact angles can be further improved, by at least a factor of two. Additionally, a series of drop tests from the nominal Orion impact angle of 30° indicated that severe injury risk levels would be sustained beyond impact velocities of 5 m/s. This is a result of the differential stroking of the airbags within the system causing a shearing effect between the occupant seat structure and the spacecraft floor, removing significant stroke from the airbags.

The effects of airbags and seatbelts on occupant injury in longitudinal barrier crashes.

PubMed

Gabauer, Douglas J; Gabler, Hampton C

2010-02-01

Longitudinal barriers, such as guardrails, are designed to prevent a vehicle that leaves the roadway from impacting a more dangerous object while minimizing the risk of injury to the vehicle occupants. Current full-scale test procedures for these devices do not consider the effect of occupant restraints such as seatbelts and airbags. The purpose of this study was to determine the extent to which restraints are used or deployed in longitudinal barrier collisions and their subsequent effect on occupant injury. Binary logistic regression models were generated to predict occupant injury risk using data from the National Automotive Sampling System / Crashworthiness Data System from 1997 through 2007. In tow-away longitudinal barrier crashes, airbag deployment rates were 70% for airbag-equipped vehicles. Compared with unbelted occupants without an airbag available, seat belt restrained occupants with an airbag available had a dramatically decreased risk of receiving a serious (MAIS 3+) injury (odds-ratio (OR)=0.03; 95% CI: 0.004-0.24). A similar decrease was observed among those restrained by seat belts, but without an airbag available (OR=0.03; 95% CI: 0.001- 0.79). No significant differences in risk of serious injuries were observed between unbelted occupants with an airbag available compared with unbelted occupants without an airbag available (OR=0.53; 95% CI=0.10-2.68). This study refutes the perception in the roadside safety community that airbags rarely deploy in frontal barrier crashes, and suggests that current longitudinal barrier occupant risk criteria may over-estimate injury potential for restrained occupants involved in a longitudinal barrier crash. Copyright 2010 Elsevier Ltd. All rights reserved.

Splenic trauma as an adverse effect of torso-protecting side airbags: biomechanical and case evidence.

PubMed

Hallman, Jason J; Brasel, Karen J; Yoganandan, Narayan; Pintar, Frank A

2009-10-01

Injury mechanisms from frontal airbags, first identified in anecdotal reports, are now well documented for pediatric, small female, and out-of-position occupants. In contrast, torso side airbags have not yet been consistently associated with specific injury risks in field assessments. To determine possible torso side airbag-related injuries, the present study identified crashes involving side airbags from reports within the CIREN, NASS, and SCI databases. Injury patterns were compared to patterns from lateral crashes in absence of side airbag. Splenic trauma (AIS 3+) was found present in five cases of torso side airbag deployment at lower impact severity (as measured by velocity change and compartment intrusion) than cases of splenic trauma without side airbag. Five additional cases were found to contain similar injury patterns but occurred with greater crash severity. To supplement case analyses, full scale sled tests were conducted with a THOR-NT dummy and cadaveric specimen. Four THOR tests with door- and seat-mounted torso side airbags confirmed that out-of-position (early inflation stage) airbag contact elevated thoracic injury metrics compared to optimal (fully inflated) contact. Out-of-position seat-mounted airbag deployment also produced AIS 3 splenic trauma in the cadaveric specimen. Due to potentially sudden or delayed onset of intraperitoneal hemorrhage and hypovolemic shock following splenic trauma, further biomechanical investigation of this anecdotal evidence is essential to identify injury mechanisms, prevention techniques, and methods for early diagnosis.

Splenic Trauma as an Adverse Effect of Torso-Protecting Side Airbags: Biomechanical and Case Evidence

PubMed Central

Hallman, Jason J.; Brasel, Karen J.; Yoganandan, Narayan; Pintar, Frank A.

2009-01-01

Injury mechanisms from frontal airbags, first identified in anecdotal reports, are now well documented for pediatric, small female, and out-of-position occupants. In contrast, torso side airbags have not yet been consistently associated with specific injury risks in field assessments. To determine possible torso side airbag-related injuries, the present study identified crashes involving side airbags from reports within the CIREN, NASS, and SCI databases. Injury patterns were compared to patterns from lateral crashes in absence of side airbag. Splenic trauma (AIS 3+) was found present in five cases of torso side airbag deployment at lower impact severity (as measured by velocity change and compartment intrusion) than cases of splenic trauma without side airbag. Five additional cases were found to contain similar injury patterns but occurred with greater crash severity. To supplement case analyses, full scale sled tests were conducted with a THOR-NT dummy and cadaveric specimen. Four THOR tests with door- and seat-mounted torso side airbags confirmed that out-of-position (early inflation stage) airbag contact elevated thoracic injury metrics compared to optimal (fully inflated) contact. Out-of-position seat-mounted airbag deployment also produced AIS 3 splenic trauma in the cadaveric specimen. Due to potentially sudden or delayed onset of intraperitoneal hemorrhage and hypovolemic shock following splenic trauma, further biomechanical investigation of this anecdotal evidence is essential to identify injury mechanisms, prevention techniques, and methods for early diagnosis. PMID:20184829

FRP debonding monitoring using OTDR techniques

NASA Astrophysics Data System (ADS)

Hou, Shuang; Cai, C. S. Steve; Ou, Jinping

2009-07-01

Debonding failure has been reported as the dominant failure mode for FRP strengthening in flexure. This paper explores a novel debonding monitoring method for FRP strengthened structures by means of OTDR-based fiber optic technology. Interface slip as a key factor in debonding failures will be measured through sensing optic fibers, which is instrumented in the interface between FRP and concrete in the direction perpendicular to the FRP filaments. Slip in the interface will induce power losses in the optic fiber signals at the intersection point of the FRP strip and the sensing optic fiber and the signal change will be detected through OTDR device. The FRP double shear tests and three-point bending tests were conducted to verify the effectiveness of the proposed monitoring method. It is found that the early bebonding can be detected before it causes the interface failure. The sensing optic fiber shows signal changes in the slip value at about 36~156 micrometer which is beyond sensing capacity of the conventional sensors. The tests results show that the proposed method is feasible in slip measurement with high sensitivity, and would be cost effective because of the low price of sensors used, which shows its potential of large-scale applications in civil infrastructures, especially for bridges.

Minimizing the injury potential of deploying airbag interactions with car occupants.

PubMed

Mertz, Harold J; Prasad, Priya; Dalmotas, Dainius

2013-11-01

Minimizing the injury potential of the interactions between deploying airbags and car occupants is the major issue with the design of airbag systems. This concern was identified in 1964 by Carl Clark when he presented the results of human volunteer and dummy testing of the "Airstop" system that was being developed for aircraft. The following is a chronological summary of the actions taken by the car manufacturers, airbag suppliers, SAE and ISO task groups, research institutes and universities, and consumer and government groups to address this issue.

Soil disturbance by airbags

NASA Technical Reports Server (NTRS)

1997-01-01

Disturbance of the drift at the Pathfinder landing site reveals a shallow subsurface that is slightly darker but has similar spectral properties. The top set of images, in true color, shows the soils disturbed by the last bounce of the lander on its airbags before coming to rest and the marks created by retraction of the airbags. In the bottom set of images color differences have been enhanced. The mast at center is the Atmospheric Structure Instrument/Meteorology Package (ASI/MET). The ASI/MET is an engineering subsytem that acquired atmospheric data during Pathfinder's descent, and will continue to get more data through the entire landed mission. A shadow of the ASI/MET appears on a rock at left.

Mars Pathfinder was developed and managed by the Jet Propulsion Laboratory (JPL) for the National Aeronautics and Space Administration. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

Severe upper extremity injuries in frontal automobile crashes: the effects of depowered airbags.

PubMed

Jernigan, M Virginia; Rath, Amber L; Duma, Stefan M

2005-03-01

The purpose of this study was to determine the effects of depowered frontal airbags on the incidence of severe upper extremity injuries. The National Automotive Sampling System database files from 1993 to 2000 were examined in a study that included 2,413,347 occupants who were exposed to an airbag deployment in the United States. Occupants exposed to a depowered airbag deployment were significantly more likely to sustain a severe upper extremity injury (3.9%) than those occupants exposed to a full-powered airbag deployment (2.5%) (P=.01). Full-powered systems resulted in an injury distribution of 89.2% fractures and 7.9% dislocations compared with depowered systems with 55.3% fractures and 44.3% dislocations. Although depowered airbags were designed to reduce the risk of injuries, they appear to have increased the overall incidence of severe upper extremity injuries through a shift from long bone fractures to joint dislocations.

[Development of visible-light cured FRP denture].

PubMed

Yu, P Y

1990-06-01

Acrylic denture may be fractured easily because it has a relatively poor resistance to stresses of impact, and the thick acrylic denture base also uncomforted to denture wearers. In this study, for improvement of the mechanical properties, the FRP is applied to the denture base, and try to make a thin denture base. Using the visible light-curing system, the laboratory fabrication time is saved dramatically. To develop the visible light-cured FRP denture base, with various combination of matrix resins and reinforcements, the physical properties of FRP plates were investigated first. From the results of the bending test, hardness test, and manipulation considering, the sateen weave's glasscloth was choose as the reinforcement of the prepreg. The matrix resin of Bis-GMA/UDMA/3G at 48/48/4 wt% was determined. The 3 plies glasscloth included FRP plate is 0.8 mm thickness has the maximum bending strength about 50 kgf/mm2, which is about 5 times larger than that of acrylic resin. Succeeding the study of above, the FRP denture base was fabricated by using the 0.8 mm thickness 3 plies included prepreg. This repreg is manufactured in sheet form beforehand, which is ease to manipulate at laboratory. By using the visible light curing system, it is only taken 10 min. to make a FRP denture base. The following procedures of fabricating a FRP denture is the same as metalplate denture. The visible-light cured FRP denture has some advantages such as accuracy of fit, ease of fabrication and manipulation, and only 0.8 mm thickness but has superior strength.

Self-sensing concrete-filled FRP tubes using FBG strain sensors

NASA Astrophysics Data System (ADS)

Yan, Xin; Li, Hui

2007-07-01

Concrete-filled fiber-reinforced polymer (FRP) tube is a type of newly developed structural column. It behaves brittle failure at its peak strength, and so the health monitoring on the hoop strain of the FRP tube is essential for the life cycle safety of the structure. Herein, three types of FRP tubes including 5-ply tube, 2-ply tube with local reinforcement and FRP-steel composite tube were embedded with the optic fiber Bragg grating (FBG) strain sensors in the inter-ply of FRP or the interface between FRP and steel in the middle height and the hoop direction. The compressive behaviors of the concrete-filled FRP tubes were experimentally studied. The hoop strains of the FRP tubes were recorded in real time using the embedded FBG strain sensors as well as the embedded or surface electric resistance strain gauges. Results indicated that the FBG strain sensors can faithfully record the hoop strains of the FRP tubes in compression as compared with the embedded or surface electric resistance strain gauges, and the strains recorded can reach more than μɛ.

Biomechanical and injury response to posterolateral loading from torso side airbags.

PubMed

Hallman, Jason J; Yoganandan, Narayan; Pintar, Frank A

2010-11-01

This study characterized thoracoabdominal response to posterolateral loading from a seat-mounted side airbag. Seven unembalmed post-mortem human subjects were exposed to ten airbag deployments. Subjects were positioned such that the deploying airbag first contacted the posterolateral thorax between T6 and L1 while stationary (n = 3 x 2 aspects) or while subjected to left lateral sled impact at ΔV = 6.7 m/s (n = 4). Chestband contours were analyzed to quantify deformation direction in the thoracic x-y plane (zero degrees indicating anterior and 180° indicating posterior), magnitude, rate, and viscous response. Skeletal injuries were consistent with posterolateral contact; visceral injuries consisted of renal (n = 1) or splenic (n = 3) lacerations. Deformation direction was transient during sled impact, progressing from 122 ± 5° at deformation onset to 90° following maximum deflection. Angles from stationary subjects progressed from 141 ± 9° to 120°. Peak normalized deflections, peak rates, and VCmax ranges were 0.075 - 0.171, 3.7 - 12.7 m/s, and 0.3 - 0.6 m/s with stationary airbag, respectively; ranges were 0.167 - 0.297, 7.4 - 18.3 m/s, and 0.7 - 3.0 m/s with airbag sled impact, respectively. Peak deflections were measured at angles between 99° - 135° and 98° - 125° for stationary and dynamic conditions, respectively. Because of deflection angle transience and localized injury response, both posterolateral and lateral injury metrics may be required for this boundary condition. Contrasted with flat rigid or anterolateral loading, biomechanical response to side airbag interaction may be augmented by peak normalized deflection or VCmax at 130°.

Next-generation airbags and the possibility of negative outcomes due to thoracic injury.

PubMed

Khouzam, Rami N; Al-Mawed, Saleem; Farah, Victor; Mizeracki, Adam

2014-04-01

Airbags have been shown to decrease morbidity and mortality associated with motor vehicle accidents when used in conjunction with seat belts. Airbag deployment alone however, has recently been implicated as a cause of significant thoracic injuries to unrestrained drivers. Resulting injuries include major cardiovascular and pulmonary complications. Airbags provide safety to occupants of cars and reduce mortality by 25%-30%. When not used in accordance with international standards, however, they can cause serious injury. We searched online databases from 1970 to January 2013 and included 17 retrospective studies, 12 systematic review articles, 18 case reports, 5 prospective studies, 1 lab study, 3 cohort studies, and 1 meta-analysis. Outcomes included clinical/functional response, left ventricular remodelling, hospitalizations, and mortality. Physicians must maintain a high index of suspicion for injury when evaluating drivers who were not wearing seat belts when airbags deployed, regardless of the speed of the collision, because increased risk of thoracic injury with airbags has been described in the literature. Our review indicates that even new technology, specifically the side air bag, has been associated with a risk of thoracic injury. Considering that regulations are a driving force for airbag technology, further research and scrutiny by medical teams is needed to consider the effects of airbag technology advancements on morbidity and mortality rates of car accidents, to help in guiding further improvement, and to help lawmakers in implementing rules that protect the safety of occupants. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Bumper and grille airbags concept for enhanced vehicle compatibility in side impact: phase II.

PubMed

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

Biomechanical and Injury Response to Posterolateral Loading from Torso Side Airbags

PubMed Central

Hallman, Jason J.; Yoganandan, Narayan; Pintar, Frank A.

2013-01-01

This study characterized thoracoabdominal response to posterolateral loading from a seat-mounted side airbag. Seven unembalmed post-mortem human subjects were exposed to ten airbag deployments. Subjects were positioned such that the deploying airbag first contacted the posterolateral thorax between T6 and L1 while stationary (n = 3 × 2 aspects) or while subjected to left lateral sled impact at ΔV = 6.7 m/s (n = 4). Chestband contours were analyzed to quantify deformation direction in the thoracic x–y plane (zero degrees indicating anterior and 180° indicating posterior), magnitude, rate, and viscous response. Skeletal injuries were consistent with posterolateral contact; visceral injuries consisted of renal (n = 1) or splenic (n = 3) lacerations. Deformation direction was transient during sled impact, progressing from 122 ± 5° at deformation onset to 90° following maximum deflection. Angles from stationary subjects progressed from 141 ± 9° to 120°. Peak normalized deflections, peak rates, and VCmax ranges were 0.075 – 0.171, 3.7 – 12.7 m/s, and 0.3 – 0.6 m/s with stationary airbag, respectively; ranges were 0.167 – 0.297, 7.4 – 18.3 m/s, and 0.7 – 3.0 m/s with airbag sled impact, respectively. Peak deflections were measured at angles between 99° – 135° and 98° – 125° for stationary and dynamic conditions, respectively. Because of deflection angle transience and localized injury response, both posterolateral and lateral injury metrics may be required for this boundary condition. Contrasted with flat rigid or anterolateral loading, biomechanical response to side airbag interaction may be augmented by peak normalized deflection or VCmax at 130°. PMID:21512911

Seat belts are more effective than airbags in reducing thoracic aortic injury in frontal motor vehicle crashes.

PubMed

Brasel, Karen J; Quickel, Robert; Yoganandan, Narayan; Weigelt, John A

2002-08-01

Airbags reduce the probability of death in frontal collisions, but the effect is small compared with seat belts. Little is known about the influence of seat belts and airbags on the incidence of thoracic aortic injury (TAI). The National Automotive Sampling System database was queried for the years 1993 to 1998 to determine the impact of seat belts and airbags on the incidence of TAI in survivors of frontal motor vehicle crashes. Proportions were compared using the two-sample Z test. Seat belts prevent TAI regardless of airbag deployment. The effect of airbags is limited to those wearing seat belts. In frontal collisions without seat belt use, airbag deployment does not alter TAI incidence. Seat belts are considerably more effective in preventing TAI than airbags after frontal motor vehicle crashes. Prevention efforts should continue to emphasize the use of active restraints. Restraint use should be considered a risk factor in evaluating patients for potential TAI.

Impact of airbags on a Level I trauma center: injury patterns, infectious morbidity, and hospital costs.

PubMed

Williams, Regan F; Fabian, Timothy C; Fischer, Peter E; Zarzaur, Ben L; Magnotti, Louis J; Croce, Martin A

2008-05-01

To date, no study has evaluated the potential impact of supplemental restraint use on resource use at a Level I trauma center. We hypothesized that airbag use would be related to decreased injury severity of motor vehicle collision survivors admitted to a Level I trauma center, leading to a decrease in infectious morbidity and hospital resource use. Using the trauma registry, motor vehicle collision victims admitted during an 11-year period were identified. Restraint groups were defined as unrestrained (reference group), seatbelt only, airbag only, or airbag and seatbelt. Multivariable logistic regression was used to determine the relationship between restraint type and injury patterns. Other outcomes measured included prevalence of ventilator-associated pneumonia and bacteremia, hospital length of stay, days in the ICU, and hospital mortality. A total of 14,390 patients (unrestrained, n = 7,881; airbag only, n = 692; seatbelt only, n = 4,909; airbag and seatbelt, n = 908) had restraint data available. Both airbag and seatbelt use were associated with a substantial reduction in injury to the brain, face, cervical spine, thorax, and abdomen. The largest reduction occurred when these restraints were used in combination. The only injury associated with airbag deployment was extremity fractures. Compared with unrestrained persons, any restraint use was associated with substantially reduced injury severity, significant infectious morbidity, and resource use. Airbags are associated with reduced in-hospital mortality. Airbags are also associated with decreased injury severity, substantial infectious morbidity, and resource use. Cost savings from reduced resource use associated with supplemental restraints could be tremendous.

Special issue : new federal airbag rule

DOT National Transportation Integrated Search

2000-06-17

time the federal government has issued a regulation to protect people from the safety : systems in their cars. Besides assuring that airbags will continue to prevent deaths and : injuries in serious crashes, the new standard for occupant protection i...

Martian Surface & Pathfinder Airbags

NASA Image and Video Library

1997-07-05

This image of the Martian surface was taken in the afternoon of Mars Pathfinder's first day on Mars. Taken by the Imager for Mars Pathfinder (IMP camera), the image shows a diversity of rocks strewn in the foreground. A hill is visible in the distance (the notch within the hill is an image artifact). Airbags are seen at the lower right. http://photojournal.jpl.nasa.gov/catalog/PIA00612

Field Data on Head Injuries in Side Airbag Vehicles in Lateral Impact

PubMed Central

Yoganandan, Narayan; Pintar, Frank A.; Gennarelli, Thomas A.

2005-01-01

Field data on side airbag deployments in lateral crashes and head injuries have largely remained anecdotal. Consequently, the purpose of this research was to report head injuries in lateral motor vehicle impacts. Data from the National Automotive Sampling System files were extracted from side impacts associated with side airbag deployments. Matched pairs with similar vehicle characteristics but without side airbags were also extracted. All data were limited to the United States Federal Motor vehicle Safety Standards FMVSS 214 compliant vehicles so that the information may be more effectively used in the future. In this study, some fundamental analyses are presented regarding occupant- and vehicle-related parameters. PMID:16179147

Experimental evaluation and design of unfilled and concrete-filled FRP composite piles, task 1 - mechanical properties of FRP piles.

DOT National Transportation Integrated Search

2014-10-01

The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP : composite piles for load-bearing in bridges. This report covers Task 1, Mechanical Properties of FRP Piles. : Mechanical and geotechnic...

Experimental evaluation and design of unfilled and concrete-filled FRP composite piles, task 3 - FRP composite pile flexural testing.

DOT National Transportation Integrated Search

2014-06-01

The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP : composite piles for load-bearing in bridges. This report covers Task 3, FRP Composite Pile Flexural Testing. : Hollow and concrete filled...

Injury risks between first- and second-generation airbags in frontal motor vehicle collisions.

PubMed

MacLennan, Paul A; Ashwander, William S; Griffin, Russell; McGwin, Gerald; Rue, Loring W

2008-07-01

Airbags in vehicles manufactured after 1997 were depowered to decrease injury risks for infants/children and small adults. It is possible that compared to earlier airbags second-generation airbags provide less injury protection due to their depowered nature. A cohort study was conducted using 1995-2004 national data. Risk ratios (RRs) and 95% confidence intervals (CIs) compared injury risks for occupants involved in frontal collisions in vehicles wherein a first- or second-generation airbag deployed by body region and injury severity using the Abbreviated Injury Scale (AIS). Associations were adjusted for crash severity, seatbelt use, seat position, occupant location, and vehicle curb weight. For upper extremity injuries reduced RRs were observed for AIS 1 or greater (RR=0.76, CI 0.67-0.86), AIS 2 or greater (RR=0.76, CI 0.58-1.00) and AIS 3 (RR=0.81, CI 0.64-1.03). Elevated risks were observed for AIS 5 thoracic injuries (RR=1.46, CI 1.04-2.07) but were made null when differences in age and gender were adjusted for. Vehicles equipped with first- and second-generation airbags appear to offer similar protection for front-seated occupants. The observed decreased risks for upper extremity injury and increased risks for severe thoracic injuries warrant further attention.

Feasibility Study of an Airbag-Based Crew Impact Attenuation System for the Orion MPCV

NASA Technical Reports Server (NTRS)

Do, Sydney; deWeck, Olivier

2011-01-01

Airbag-based methods for crew impact attenuation have been highlighted as a potential lightweight means of enabling safe land-landings for the Orion Multi-Purpose Crew Vehicle, and the next generation of ballistic shaped spacecraft. To investigate the performance feasibility of this concept during a nominal 7.62m/s Orion landing, a full-scale personal airbag system 24% lighter than the Orion baseline has been developed, and subjected to 38 drop tests on land. Through this effort, the system has demonstrated the ability to maintain the risk of injury to an occupant during a 7.85m/s, 0 deg. impact angle land-landing to within the NASA specified limit of 0.5%. In accomplishing this, the airbag-based crew impact attenuation concept has been proven to be feasible. Moreover, the obtained test results suggest that by implementing anti-bottoming airbags to prevent direct contact between the system and the landing surface, the system performance during landings with 0 deg impact angles can be further improved, by at least a factor of two. Additionally, a series of drop tests from the nominal Orion impact angle of 30 deg indicated that severe injury risk levels would be sustained beyond impact velocities of 5m/s. This is a result of the differential stroking of the airbags within the system causing a shearing effect between the occupant seat structure and the spacecraft floor, removing significant stroke from the airbags.

Experimental evaluation and design of unfilled and concrete-filled FRP composite piles, task 6 - FRP composite pile axial compression testing.

DOT National Transportation Integrated Search

2015-04-01

The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP : composite piles for load-bearing in bridges. This report covers Task 6, FRP Composite Pile Axial Compression : Testing. : Hollow and conc...

Complex Multi-Chamber Airbag Performance Simulation Final Report CRADA No. TSB-961-94

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

Kay, Gregory; Kithil, Philip

The purpose of this small business CRADA was to evaluate the performance of new airbag concepts which were developed by the Advanced Safety Concepts, Inc. (ASCI). These new airbag concepts, if successful, could have major potential savings to society in terms of fewer injuries, lost time and lives.

Dynamic strain distribution of FRP plate under blast loading

NASA Astrophysics Data System (ADS)

Saburi, T.; Yoshida, M.; Kubota, S.

2017-02-01

The dynamic strain distribution of a fiber re-enforced plastic (FRP) plate under blast loading was investigated using a Digital Image Correlation (DIC) image analysis method. The testing FRP plates were mounted in parallel to each other on a steel frame. 50 g of composition C4 explosive was used as a blast loading source and set in the center of the FRP plates. The dynamic behavior of the FRP plate under blast loading were observed by two high-speed video cameras. The set of two high-speed video image sequences were used to analyze the FRP three-dimensional strain distribution by means of DIC method. A point strain profile extracted from the analyzed strain distribution data was compared with a directly observed strain profile using a strain gauge and it was shown that the strain profile under the blast loading by DIC method is quantitatively accurate.

A Summary of the Development of a Nominal Land Landing Airbag Impact Attenuation System for the Orion Crew Module

NASA Technical Reports Server (NTRS)

Tutt, Ben; Gill, Susannah; Wilson, Aaron; Johnson, Keith

2009-01-01

Airborne Systems North America (formally Irvin Aerospace Inc) has developed an Airbag Landing System for the Orion Crew Module of the Crew Exploration Vehicle. This work is in support of the NASA Langley Research Center Landing System Advanced Development Project. Orion is part of the Constellation Program to send human explorers back to the moon, and then onwards to Mars and other destinations in the Solar System. A component of the Vision for Space Exploration, Orion is being developed to also enable access to space following the retirement of the Space Shuttle in the next decade. This paper documents the development of a conceptual design, fabrication of prototype assemblies, component level testing and two generations of airbag landing system testing. The airbag system has been designed and analyzed using the transient dynamic finite element code LS-DYNA(RegisteredTradeMark). The landing system consists of six airbag assemblies; each assembly comprising a primary impact venting airbag and a non-venting anti-bottoming airbag. The anti-bottoming airbag provides ground clearance following the initial impact attenuation sequence. Incorporated into each primary impact airbag is an active vent that allows the entrapped gas to exit the control volume. The size of the vent is tailored to control the flow-rate of the exiting gas. An internal shaping structure is utilized to control the shape of the primary or main airbags prior to ground impact; this significantly improves stroke efficiency and performance.

Behaviour of concrete beams reinforced withFRP prestressed concrete prisms

NASA Astrophysics Data System (ADS)

Svecova, Dagmar

The use of fibre reinforced plastics (FRP) to reinforce concrete is gaining acceptance. However, due to the relatively low modulus of FRP, in comparison to steel, such structures may, if sufficient amount of reinforcement is not used, suffer from large deformations and wide cracks. FRP is generally more suited for prestressing. Since it is not feasible to prestress all concrete structures to eliminate the large deflections of FRP reinforced concrete flexural members, researchers are focusing on other strategies. A simple method for avoiding excessive deflections is to provide sufficiently high amount of FRP reinforcement to limit its stress (strain) to acceptable levels under service loads. This approach will not be able to take advantage of the high strength of FRP and will be generally uneconomical. The current investigation focuses on the feasibility of an alternative strategy. This thesis deals with the flexural and shear behaviour of concrete beams reinforced with FRP prestressed concrete prisms. FRP prestressed concrete prisms (PCP) are new reinforcing bars, made by pretensioning FRP and embedding it in high strength grout/concrete. The purpose of the research is to investigate the feasibility of using such pretensioned rebars, and their effect on the flexural and shear behaviour of reinforced concrete beams over the entire loading range. Due to the prestress in the prisms, deflection of concrete beams reinforced with this product is substantially reduced, and is comparable to similarly steel reinforced beams. The thesis comprises both theoretical and experimental investigations. In the experimental part, nine beams reinforced with FRP prestressed concrete prisms, and two companion beams, one steel and one FRP reinforced were tested. All the beams were designed to carry the same ultimate moment. Excellent flexural and shear behaviour of beams reinforced with higher prestressed prisms is reported. When comparing deflections of three beams designed to have the

Applications of FRP-OFBG sensors on bridge cables

NASA Astrophysics Data System (ADS)

Zhou, Zhi; Zhang, Zhichun; Deng, Nianchun; Zhao, Xuefeng; Li, Dongsheng; Wang, Chuang; Ou, Jinping

2005-05-01

It is still a practical problem how to effectively install FBG sensors on bridge cabes. In this paper, a simple and effective solution is introduced to develop smart bridge cables using FRP-OFBG bars developed in HIT (Harbin Institute of Technology). Here, the FRP-OFBG bar acts as one component of the cable and shows force resistance and well-protected sensors in service. The installation techniques and the sensing properties of FBGs in three kinds of cables, FRP cables, common steel-wire cable and extruded-anchor cable, are introduced and tested under dead load. Moreover, the preliminary introduction of a practical field application based on this solution has been also given. The experimental results show that the deformability of FRP-OFBG bars in the smart cables can reach the terminal and show wonderful accuracy, which shows that such kind of smart cable is practical in field application.

Airbag retraction

NASA Technical Reports Server (NTRS)

1997-01-01

This image shows that the Mars Pathfinder airbags have been successfully retracted, allowing safe deployment of the rover ramps. The Sojourner rover is at lower right, and rocks are visible in the background. Mars Pathfinder landed successfully on the surface of Mars today at 10:07 a.m. PDT.

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

Airbag retraction

NASA Technical Reports Server (NTRS)

1997-01-01

This image shows that the Mars Pathfinder airbags have been successfully retracted, allowing safe deployment of the rover ramps. The Sojourner rover, still in its deployed position, is at center image, and rocks are visible in the background. Mars Pathfinder landed successfully on the surface of Mars today at 10:07 a.m. PDT.

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

Injury Patterns Sustained in Fatal Motor Vehicle Collisions with Driver's Third-Generation Airbag Deployment.

PubMed

Kuk, Mariya; Shkrum, Michael J

2018-05-01

The Office of the Chief Coroner for Ontario database for 2011-2012 was used to compare fatal injury patterns in drivers whose third-generation airbags deployed compared to first- and second-generation airbag deployments and airbag nondeployments with and without seatbelt use. There were 110 frontal and offset frontal crashes analyzed. The small sample size meant that the odds of craniocerebral, cervical spinal, thoracic, and abdominal injuries were not statistically different for airbag generation, deployment status, and seatbelt use; however, the risk of fatal thoracic injuries in third- and second-generation cases was increased. Seatbelt usage in third- and second-generation deployment cases reduced the risk of all injuries except abdominal trauma. High severity impacts and occupant compartment intrusion were frequently observed. The analyses in this retrospective study were challenged by data that were not collated in a standardized way and were limited in details about scene, vehicle, and driver variables. © 2017 American Academy of Forensic Sciences.

Elimination of deck joints using a corrosion resistant FRP approach

NASA Astrophysics Data System (ADS)

Aleti, Ashok Reddy

The research presented herein describes the development of durable link slabs for jointless bridge decks based on using FRP grid for reinforcement. Specifically, the ductility of the FRP material was utilized to accommodate bridge deck deformations imposed by girder deflection, temperature variations, and concrete shrinkage. It would also provide a solution to a number of deterioration problems associated with bridge deck joints. The design concept of the link slabs was then examined to form the basis of design for FRP grid link slabs. Improved design of FRP grid link slab/concrete deck slab interface was confirmed in the numerical analysis. The mechanical properties between the FRP grid and concrete were evaluated. The behavior of the link slab was investigated and confirmed for durability. The results indicated that the technique would allow simultaneous achievement of structural need (lower flexural stiffness of the link slab approaching the behavior of a hinge) and durability need of the link slab. Also, the development length results confirm that the bond between the FRP grid and the concrete was highly improved. The overall investigation supports the contention that durable jointless concrete bridge decks may be designed and constructed with FRP grid link slabs. It is recommended that the link slab technique be used during new construction of the bridge decks and in repair and retrofit of the bridge decks.

FRP/steel composite damage acoustic emission monitoring and analysis

NASA Astrophysics Data System (ADS)

Li, Dongsheng; Chen, Zhi

2015-04-01

FRP is a new material with good mechanical properties, such as high strength of extension, low density, good corrosion resistance and anti-fatigue. FRP and steel composite has gotten a wide range of applications in civil engineering because of its good performance. As the FRP/steel composite get more and more widely used, the monitor of its damage is also getting more important. To monitor this composite, acoustic emission (AE) is a good choice. In this study, we prepare four identical specimens to conduct our test. During the testing process, the AE character parameters and mechanics properties were obtained. Damaged properties of FRP/steel composite were analyzed through acoustic emission (AE) signals. By the growing trend of AE accumulated energy, the severity of the damage made on FRP/steel composite was estimated. The AE sentry function has been successfully used to study damage progression and fracture emerge release rate of composite laminates. This technique combines the cumulative AE energy with strain energy of the material rather than analyzes the AE information and mechanical separately.

Patterns of Injury Among Drivers Hospitalized in Level-I Trauma Centers: Have Frontal Airbags Made a Difference?

PubMed Central

Segui-Gomez, Maria; Graham, John D.

2000-01-01

This study describes the injuries of drivers discharged from Level-I Trauma Centers between 1995–1997. Differences in the drivers’ injuries and outcomes by airbag deployment status and gender were evaluated using Chi2 and T-tests. Data on 1,065 drivers (66 with airbags, 423 females) were obtained from the Massachusetts Registry of Motor Vehicle and Trauma Registries. Once admitted to trauma centers, drivers with airbags did not differ from drivers without airbags regarding the number, type, clustering, severity or outcome of their injuries. The only exception was that female drivers sustained more fractures to the upper extremities and less injuries to blood vessels and certain traumatic complications (p<0.05). PMID:11558082

An experimental study on the shear strength of FRP perfobond shear connector

NASA Astrophysics Data System (ADS)

Gwon, S. C.; Kim, S. H.; Yoon, S. J.; Choi, C. W.

2018-06-01

In this study, push-out tests were conducted to investigate shear behaviour of FRP perfobond shear connector. The parameters influencing shear capacity of FRP perfobond shear connector are concrete dowel effect, shear resistance effect of the laterally reinforced FRP re- bar, and frictional effect between shear connector and concrete. The specimens were designed to consider these parameters. The specimens coated with sand to increase frictional resistance between the FRP re-bar and concrete. Based on the test results and the parameters, new equation was suggested to predict shear strength of FRP perfobond shear connectors. The predicted results and the experimental results were compared to check the feasibility of prediction.

Airbag Tracks on Mars

NASA Technical Reports Server (NTRS)

2004-01-01

The circular shapes seen on the martian surface in these images are 'footprints' left by the Mars Exploration Rover Opportunity's airbags during landing as the spacecraft gently rolled to a stop. Opportunity landed at approximately 9:05 p.m. PST on Saturday, Jan. 24, 2004, Earth-received time. The circular region of the flower-like feature on the right is about the size of a basketball. Scientists are studying the prints for more clues about the makeup of martian soil. The images were taken at Meridiani Planum, Mars, by the panoramic camera on the Mars Exploration Rover Opportunity.

Splicing and local reinforcement of concrete filled FRP tubes.

DOT National Transportation Integrated Search

2014-01-01

This report includes fulfillment of Task 1 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 1 investigates and develops a feasible solution for splicing the concrete filled FRP : tubes. This w...

A development of visible light cured FRP plate denture.

PubMed

Kimura, H; Teraoka, F

1990-12-01

A FRP denture base, which was made from visible light curing prepreg, was developed. The visible light cured FRP denture base had advantages with respect to an adequate strength, bonding strength of acrylic base resin, esthetic properties and ease to manipulation. The matrix resin of Bis-GMA/UDMA/3 G at 48/48/4 was determined from the results of the bending test and manipulation processing. The sateen weave's glasscloth was used for the reinforcement of the prepreg. The adaptability of the FRP plate denture was better than that of the resin base denture constructed with microwave heating.

Rocky terrain & airbags

NASA Technical Reports Server (NTRS)

1997-01-01

An area of very rocky terrain at the Ares Vallis landing site, along with the lander's deflated airbags, were imaged by the Imager for Mars Pathfinder (IMP) before its deployment on Sol 2. The metallic object at the bottom is a bracket for the IMP's release mechanism.

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

Upper extremity interaction with a helicopter side airbag: injury criteria for dynamic hyperextension of the female elbow joint.

PubMed

Duma, Stefan M; Hansen, Gail A; Kennedy, Eric A; Rath, Amber L; McNally, Craig; Kemper, Andrew R; Smith, Eric P; Brolinson, P Gunnar; Stitzel, Joel D; Davis, Martin B; Bass, Cameron R; Brozoski, Frederick T; McEntire, B Joseph; Alem, Nabih M; Crowley, John S

2004-11-01

This paper describes a three part analysis to characterize the interaction between the female upper extremity and a helicopter cockpit side airbag system and to develop dynamic hyperextension injury criteria for the female elbow joint. Part I involved a series of 10 experiments with an original Army Black Hawk helicopter side airbag. A 5(th) percentile female Hybrid III instrumented upper extremity was used to demonstrate side airbag upper extremity loading. Two out of the 10 tests resulted in high elbow bending moments of 128 Nm and 144 Nm. Part II included dynamic hyperextension tests on 24 female cadaver elbow joints. The energy source was a drop tower utilizing a three-point bending configuration to apply elbow bending moments matching the previously conducted side airbag tests. Post-test necropsy showed that 16 of the 24 elbow joint tests resulted in injuries. Injury severity ranged from minor cartilage damage to more moderate joint dislocations and severe transverse fractures of the distal humerus. Peak elbow bending moments ranged from 42.4 Nm to 146.3 Nm. Peak bending moment proved to be a significant indicator of any elbow injury (p = 0.02) as well as elbow joint dislocation (p = 0.01). Logistic regression analyses were used to develop single and multiple variate injury risk functions. Using peak moment data for the entire test population, a 50% risk of obtaining any elbow injury was found at 56 Nm while a 50% risk of sustaining an elbow joint dislocation was found at 93 Nm for the female population. These results indicate that the peak elbow bending moments achieved in Part I are associated with a greater than 90% risk for elbow injury. Subsequently, the airbag was re-designed in an effort to mitigate this as well as the other upper extremity injury risks. Part III assessed the redesigned side airbag module to ensure injury risks had been reduced prior to implementing the new system. To facilitate this, 12 redesigned side airbag deployments were conducted

Nde of Frp Wrapped Columns Using Infrared Thermography

NASA Astrophysics Data System (ADS)

Halabe, Udaya B.; Dutta, Shasanka Shekhar; GangaRao, Hota V. S.

2008-02-01

This paper investigates the feasibility of using Infrared Thermography (IRT) for detecting debonds in Fiber Reinforced Polymer (FRP) wrapped columns. Laboratory tests were conducted on FRP wrapped concrete cylinders of size 6″×12″ (152.4 mm×304.8 mm) in which air-filled and water-filled debonds of various sizes were placed underneath the FRP wraps. Air-filled debonds were made by cutting plastic sheets into the desired sizes whereas water-filled debonds were made by filling water in custom made polyethylene pouches. Both carbon and glass fiber reinforced wraps were considered in this study. Infrared tests were conducted using a fully radiometric digital infrared camera which was successful in detecting air-filled as well as water-filled subsurface debonds. In addition to the laboratory testing, two field trips were made to Moorefield, West Virginia for detecting subsurface debonds in FRP wrapped timber piles of a railroad bridge using infrared testing. The results revealed that infrared thermography can be used as an effective nondestructive evaluation tool for detecting subsurface debonds in structural components wrapped with carbon or glass reinforced composite fabrics.

Deformation Analysis of RC Ties Externally Strengthened with FRP Sheets

NASA Astrophysics Data System (ADS)

Gribniak, V.; Arnautov, A. K.; Kaklauskas, G.; Jakstaite, R.; Tamulenas, V.; Gudonis, E.

2014-11-01

The current study has two objectives: to validate the ability of the Atena finite-element software to estimate the deformations of reinforced concrete (RC) elements strengthened with fiber-reinforced polymer (FRP) sheets and to assess the effect of FRP-to-concrete bond strength on the results of numerical simulation. It is shown that the bond strength has to be selected according to the overall stiffness of the composite element. The numerical results found are corroborated experimentally by tensile tests of RC elements strengthened with basalt FRP sheets.

Development of ductile hybrid fiber reinforced polymer (D-H-FRP) reinforcement for concrete structures

NASA Astrophysics Data System (ADS)

Somboonsong, Win

The corrosion of steel rebars has been the major cause of the reinforced concrete deterioration in transportation structures and port facilities. Currently, the Federal Highway Administration (FHWA) spends annually $31 billion for maintaining and repairing highways and highway bridges. The study reported herein represents the work done in developing a new type of reinforcement called Ductile Hybrid Fiber Reinforced Polymer or D-H-FRP using non-corrosive fiber materials. Unlike the previous FRP reinforcements that fail in a brittle manner, the D-H-FRP bars exhibit the stress-strain curves that are suitable for concrete reinforcement. The D-H-FRP stress-strain curves are linearly elastic with a definite yield point followed by plastic deformation and strain hardening resembling that of mild steel. In addition, the D-H-FRP reinforcement has integrated ribs required for concrete bond. The desirable mechanical properties of D-H-FRP reinforcement are obtained from the integrated design based on the material hybrid and geometric hybrid concepts. Using these concepts, the properties can be tailored to meet the specific design requirements. An analytical model was developed to predict the D-H-FRP stress-strain curves with different combination of fiber materials and geometric configuration. This model was used to optimize the design of D-H-FRP bars. An in-line braiding-pultrusion manufacturing process was developed at Drexel University to produce high quality D-H-FRP reinforcement in diameters that can be used in concrete structures. A series of experiments were carried out to test D-H-FRP reinforcement as well as their individual components in monotonic and cyclic tensile tests. Using the results from the tensile tests and fracture analysis, the stress-strain behavior of the D-H-FRP reinforcement was fully characterized and explained. Two series of concrete beams reinforced with D-H-FRP bars were studied. The D-H-FRP beam test results were then compared with companion

Elimination of deck joints using a corrosion resistant FRP approach.

DOT National Transportation Integrated Search

2009-09-01

The research presented herein describes the development of durable link slabs for jointless bridge decks based on : using a fiber reinforced polymer (FRP) grid for reinforcement. Specifically the ductility of the FRP material was : utilized to accomm...

Elimination of deck joints using a corrosion resistant FRP approach.

DOT National Transportation Integrated Search

2009-09-01

The research presented herein describes the development of durable link slabs for jointless bridge decks based on using a fiber reinforced polymer (FRP) grid for reinforcement. Specifically the ductility of the FRP material was utilized to accommodat...

Analysis of particles produced during airbag deployment by scanning electron microscopy with energy dispersive x-ray spectroscopy and their deposition on surrounding surfaces: a mid-research summary

NASA Astrophysics Data System (ADS)

Wyatt, J. Matney

2011-06-01

Airbags can be encountered in forensic work when investigating a car crash and are typically constructed with primerlike material to begin the deployment apparatus. The mechanisms of airbag deployment can produce particles ideal for scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS) analysis. A recent study published by Berk studied airbags with vents and showed that it is possible for particles generated from the deployment of these airbags to deposit on surfaces in the vehicle as the airbags deflate.1 Another paper published by Berk reported particles similar in morphology and composition to primer gunshot residue (GSR) are produced by side impact airbags.2 This paper's aim will be to show mid-point results of a study still in progress in which non-vented airbags were analyzed to determine if they exhibited the same particle depositing features as their vented airbag counterparts. Further investigation in this study is being performed to find more airbags which produce primer gunshot residue-like particles containing lead, barium, and antimony from airbag deployment. To date, the study has resulted in (1) non-vented airbags exhibiting deposition of particles suitable for SEM/EDS analysis and (2) no gunshot residue-like particles being detected from the airbag residues studied thus far.

A late and failure of airbag deployment case study for drivers of passenger cars in rear-end collisions

NASA Astrophysics Data System (ADS)

Toganel, George-Radu; Ovidiu Soica, Adrian

2017-10-01

The presented study was directed at two types of airbag miss-deployments: late deployment and non-deployment. Late deployment can be a product of override or underride road traffic accidents. Non-deployment can be a product of technical failure or trigger algorithm’s inability to correctly assume the state of the accident to happen. In order to analyse the phenomena through physical tests, a specialized test device was used for a series of 8 non-deployment tests and a series of 4 airbag firing tests, totalling 12 tests. Acceleration based data was recorded and analysed for the movement of the device part simulating the driver head. High speed video recording was used to analyse the mechanics of airbag deployment and correlate with the acceleration based data. It has been determined, in the limitations of the laboratory testing environment, a significant variation of the time frame for the airbag deployments, despite using similar testing conditions and identical tested products. Also, the initial time frame for airbag deployment delay was overshadowed by other factors such as time to impact.

Study on RC beams using BOTDA(R)-FRP-OF technique

NASA Astrophysics Data System (ADS)

He, Jianping; Zhou, Zhi; Huang, Ying; Ou, Jinping

2008-03-01

Brillouin based fiber optic sensing turns to be a promising technology for Structural Health Monitoring (SHM). However, the bare optical fiber is too fragile to act as a practical sensor, so high durability and large range (large strain) Brillouin distributed sensors are in great needs in field applications. For this reason, high durable and large range optical fiber Brillouin Optical Time Domain Analysis sensors packaged by Fiber Reinforcement Polymer (FRP), named BOTDA(R)-FRP-OF, have been studied and developed. Besides, in order to study the large strain, crack and slip between the rebar and concrete in reinforced concrete (RC) beams using BOTDR(A) technique, two RC Beams installed with BOTDA(R)-FRP-OF sensors have been set up. And the damage characteristics of the RC beams were investigated by comparing the strain measured by the BOTDA(R)-FRP-OF sensors and the strain from traditional electric strain gauges. The test results show that the BOTDA(R)-FRP-OF sensor can effectively detect the damage (including crack and slip) characteristic of RC beam, and it is suitable for the long-term structural health monitoring on concrete structures such as bridge, big dam and so on.

Airbags & children: making correct choices in child passenger restraints.

PubMed

Kamerling, Susan Nudelman

2002-01-01

Countless numbers of young lives are lost each year due to motor vehicle crashes. One of the most effective means of reducing the number of children killed and injured as occupants in motor vehicles is through the use of child passenger restraints. Seat belts and child safety seats save lives and reduce the severity of injuries sustained by occupants in motor vehicle crashes. Nurses are in a unique position to educate and influence families on the proper way to safely transport all motor vehicle passengers. Therefore, nurses working with infants, children, and families have a moral and professional obligation to understand the basics of child passenger safety. At the very least, nurses should be able to direct families appropriately for specifics related to child passenger restraints. The intent of this article is to provide an overview of child passenger safety through a historical, theoretical, and clinical approach. Proper child restraint use is reviewed based on current recommendations for age and size. The potential hazards of child restraint misuse, with an in-depth discussion on airbags, is presented. The discussion on airbags serves to dispel any misconceptions that may be held about airbags. The article includes two case studies that illustrate the injury potential of relatively common misuse patterns. The clinical implications for maternal-child nurses include the recognition that child passenger deaths are primarily due to child restraint nonuse and misuse and the realization of nursing's role in the promotion of proper child passenger restraint.

The Impact of Seat belts and Airbags on High Grade Renal Injuries and Nephrectomy Rates in Motor Vehicle Collisions

PubMed Central

Bjurlin, Marc A; Fantus, Richard J.; Mellett, Michele M.; Fantus, Richard J.; Villines, Dana

2015-01-01

Purpose Motor vehicle collisions (MVCs) are the most common cause of blunt genitourinary trauma. We compared renal injuries with no protective device to those with seat belts and/or airbags utilizing the National Trauma Data Bank (NTDB). Our primary endpoint was a reduction in high-grade renal injuries (grades III-V) with a secondary endpoint of reduction in nephrectomy rate. Materials and Methods The NTDB research datasets, admission year 2010, 2011, and 2012, were queried for MVC occupants with renal injury. Subjects were stratified by protective device and airbag deployment. Abbreviated Injury Score was converted to American Association for the Surgery of Trauma renal injury grade and nephrectomy rates were evaluated. Intergroup comparisons were analyzed for renal injury grades, nephrectomy, length of stay, and mortality with chi-square or one-way ANOVA. Protective device relative risk reduction was determined. Results A review of 466,028 MVCs revealed 3,846 renal injuries. Injured occupants without a protective device had a higher rate of high grade renal injury (45.1%) compared to those with seat belts (39.9%, p=0.008), airbags (42.3%, p=0.317), and seat belts with airbags (34.7%, p<0.001). Seat belts (20.0%, p<0.001), airbags (10.5% p<0.001), and seat belts with airbags (13.3%, p<0.001) reduced the rate of nephrectomy compared to no protective device (56.2%). The combination of seatbelts and airbags also reduced total hospital length of stay (p<0.001) and ICU days (p=0.005). Relative risk reduction of high-grade renal injuries (23.1%) and nephrectomy (39.9%) were highest for combined protective devices. Conclusions Occupants of MVCs with protective devices have reduced rates of high-grade renal injury and nephrectomy. Reduction appears most pronounced with the combination of seat belts and airbags. PMID:24846798

Design and Fabrication of FRP Truck Trailer Side Racks.

DTIC Science & Technology

1983-08-01

0.100 in. All contact surfaces in the mold were sealed with white shellac and finished with five coats of carnauba wax . The completed mold is shown in...Figure 10. 15 II Figure 10. FRP prototype mold. FRP molding procedures were duplicated for each part produced. In general, the waxed mold was coated

Study on the quality of FRP fishing vessel based on improved Fishbone Chart

NASA Astrophysics Data System (ADS)

Sui, J. H.; Yu, Y. F.; Du, Q. F.; Jiang, D. W.

2018-01-01

The construction quality of FRP fishing vessels influences their production, use and industry development. In order to explore the factors that affect the construction quality of FRP fishing vessels, key factors affecting the construction quality of FRP fishing vessels are determined based on the quality problems of FRP fishing vessels constructed. The improved Fishbone Chart is used to analyze the eight factors of “human, machine, material, process, environment, inspection, design and information”. Taking the factors that affect the construction quality of FRP fishing vessels as the central target, the eight influencing factors were condensed into five aspects and a composite Fishbone Chart is drawn. The Fishbone Chart is used as the basic model, the influencing factors are sorted, screened and discriminated, and the system model convenient for construction site management and control is established. Finally, the causes of poor construction of FRP fishing vessels are analyzed and discussed, and relevant suggestions are put forward.

Development of a nondestructive evaluation method for FRP bridge decks

NASA Astrophysics Data System (ADS)

Brown, Jeff; Fox, Terra

2010-05-01

Open steel grids are typically used on bridges to minimize the weight of the bridge deck and wearing surface. These grids, however, require frequent maintenance and exhibit other durability concerns related to fatigue cracking and corrosion. Bridge decks constructed from composite materials, such as a Fiber-reinforced Polymer (FRP), are strong and lightweight; they also offer improved rideability, reduced noise levels, less maintenance, and are relatively easy to install compared to steel grids. This research is aimed at developing an inspection protocol for FRP bridge decks using Infrared thermography. The finite element method was used to simulate the heat transfer process and determine optimal heating and data acquisition parameters that will be used to inspect FRP bridge decks in the field. It was demonstrated that thermal imaging could successfully identify features of the FRP bridge deck to depths of 1.7 cm using a phase analysis process.

Experimental investigation of RC beams using BOTDA(R)-FRP-OF

NASA Astrophysics Data System (ADS)

Zhou, Zhi; He, Jianping; Huang, Ying; Ou, Jinping

2008-04-01

Brillouin based fiber optic sensing turns to be a promising technology for Structural Health Monitoring (SHM). However, the bare optical fiber is too fragile to act as a practical sensor, so high durability and large range (large strain) Brillouin distributed sensors are in great needs in field applications. For this reason, high durable and large range optical fiber Brillouin Optical Time Domain Analysis (Reflectometer) sensors packaged by Fiber Reinforcement Polymer (FRP), named BOTDA(R)-FRP-OF, have been studied and developed. Besides, in order to study the large strain, crack and slip between the rebar and concrete in reinforced concrete (RC) beams using BOTDR(A) technique, five RC Beams installed with BOTDA(R)-FRP-OF sensors have been set up. And the damage characteristics of the RC beams were investigated by comparing the strain measured by the BOTDA(R)-FRP-OF sensors and the strain from traditional electric strain gauges and Fiber Bragg Grating (FBG) sensors, respectively. The test results show that the BOTDA(R)-FRP-OF sensor can effectively detect the damage (including crack and slip) characteristic of RC beam, and it is suitable for the long-term structural health monitoring on concrete structures such as bridge, big dam and so on.

Crack Monitoring Method for an FRP-Strengthened Steel Structure Based on an Antenna Sensor.

PubMed

Liu, Zhiping; Chen, Kai; Li, Zongchen; Jiang, Xiaoli

2017-10-20

Fiber-reinforced polymer (FRP) has been increasingly applied to steel structures for structural strengthening or crack repair, given its high strength-to-weight ratio and high stiffness-to-weight ratio. Cracks in steel structures are the dominant hidden threats to structural safety. However, it is difficult to monitor structural cracks under FRP coverage and there is little related research. In this paper, a crack monitoring method for an FRP-strengthened steel structure deploying a microstrip antenna sensor is presented. A theoretical model of the dual-substrate antenna sensor with FRP is established and the sensitivity of crack monitoring is studied. The effects of the weak conductivity of carbon fiber reinforced polymers (CFRPs) on the performance of crack monitoring are analyzed via contrast experiments. The effects of FRP thickness on the performance of the antenna sensor are studied. The influence of structural strain on crack detection coupling is studied through strain-crack coupling experiments. The results indicate that the antenna sensor can detect cracks in steel structures covered by FRP (including CFRP). FRP thickness affects the antenna sensor's performance significantly, while the effects of strain can be ignored. The results provide a new approach for crack monitoring of FRP-strengthened steel structures with extensive application prospects.

Crack Monitoring Method for an FRP-Strengthened Steel Structure Based on an Antenna Sensor

PubMed Central

Liu, Zhiping; Li, Zongchen

2017-01-01

Fiber-reinforced polymer (FRP) has been increasingly applied to steel structures for structural strengthening or crack repair, given its high strength-to-weight ratio and high stiffness-to-weight ratio. Cracks in steel structures are the dominant hidden threats to structural safety. However, it is difficult to monitor structural cracks under FRP coverage and there is little related research. In this paper, a crack monitoring method for an FRP-strengthened steel structure deploying a microstrip antenna sensor is presented. A theoretical model of the dual-substrate antenna sensor with FRP is established and the sensitivity of crack monitoring is studied. The effects of the weak conductivity of carbon fiber reinforced polymers (CFRPs) on the performance of crack monitoring are analyzed via contrast experiments. The effects of FRP thickness on the performance of the antenna sensor are studied. The influence of structural strain on crack detection coupling is studied through strain–crack coupling experiments. The results indicate that the antenna sensor can detect cracks in steel structures covered by FRP (including CFRP). FRP thickness affects the antenna sensor’s performance significantly, while the effects of strain can be ignored. The results provide a new approach for crack monitoring of FRP-strengthened steel structures with extensive application prospects. PMID:29053614

LSA SAF Meteosat FRP products - Part 1: Algorithms, product contents, and analysis

NASA Astrophysics Data System (ADS)

Wooster, M. J.; Roberts, G.; Freeborn, P. H.; Xu, W.; Govaerts, Y.; Beeby, R.; He, J.; Lattanzio, A.; Fisher, D.; Mullen, R.

2015-11-01

Characterizing changes in landscape fire activity at better than hourly temporal resolution is achievable using thermal observations of actively burning fires made from geostationary Earth Observation (EO) satellites. Over the last decade or more, a series of research and/or operational "active fire" products have been developed from geostationary EO data, often with the aim of supporting biomass burning fuel consumption and trace gas and aerosol emission calculations. Such Fire Radiative Power (FRP) products are generated operationally from Meteosat by the Land Surface Analysis Satellite Applications Facility (LSA SAF) and are available freely every 15 min in both near-real-time and archived form. These products map the location of actively burning fires and characterize their rates of thermal radiative energy release (FRP), which is believed proportional to rates of biomass consumption and smoke emission. The FRP-PIXEL product contains the full spatio-temporal resolution FRP data set derivable from the SEVIRI (Spinning Enhanced Visible and Infrared Imager) imager onboard Meteosat at a 3 km spatial sampling distance (decreasing away from the west African sub-satellite point), whilst the FRP-GRID product is an hourly summary at 5° grid resolution that includes simple bias adjustments for meteorological cloud cover and regional underestimation of FRP caused primarily by underdetection of low FRP fires. Here we describe the enhanced geostationary Fire Thermal Anomaly (FTA) detection algorithm used to deliver these products and detail the methods used to generate the atmospherically corrected FRP and per-pixel uncertainty metrics. Using SEVIRI scene simulations and real SEVIRI data, including from a period of Meteosat-8 "special operations", we describe certain sensor and data pre-processing characteristics that influence SEVIRI's active fire detection and FRP measurement capability, and use these to specify parameters in the FTA algorithm and to make recommendations

The impact of seat belts and airbags on high grade renal injuries and nephrectomy rate in motor vehicle collisions.

PubMed

Bjurlin, Marc A; Fantus, Richard Jacob; Fantus, Richard Joseph; Mellett, Michele M; Villines, Dana

2014-10-01

Motor vehicle collisions are the most common cause of blunt genitourinary trauma. We compared renal injuries with no protective device to those with seat belts and/or airbags using NTDB. Our primary end point was a decrease in high grade (grades III-V) renal injuries with a secondary end point of a nephrectomy rate reduction. The NTDB research data sets for hospital admission years 2010, 2011 and 2012 were queried for motor vehicle collision occupants with renal injury. Subjects were stratified by protective device and airbag deployment. The AIS was converted to AAST renal injury grade and nephrectomy rates were evaluated. Intergroup comparisons were analyzed for renal injury grades, nephrectomy, length of stay and mortality using the chi-square test or 1-way ANOVA. The relative risk reduction of protective devices was determined. A review of 466,028 motor vehicle collisions revealed a total of 3,846 renal injuries. Injured occupants without a protective device had a higher rate of high grade renal injuries (45.1%) than those with seat belts (39.9%, p = 0.008), airbags (42.3%, p = 0.317) and seat belts plus airbags (34.7%, p <0.001). Seat belts (20.0%), airbags (10.5%) and seat belts plus airbags (13.3%, each p <0.001) decreased the nephrectomy rate compared to no protective device (56.2%). The combination of seatbelts and airbags also decreased total hospital length of stay (p <0.001) and intensive care unit days (p = 0.005). The relative risk reductions of high grade renal injuries (23.1%) and nephrectomy (39.9%) were highest for combined protective devices. Occupants of motor vehicle collisions with protective devices show decreased rates of high grade renal injury and nephrectomy. Reduction appears most pronounced with the combination of seat belts and airbags. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Polyurethane foam infill for fiber-reinforced polymer (FRP) bridge deck panels.

DOT National Transportation Integrated Search

2014-05-01

Although still in their infancy, fiber-reinforced polymer (FRP) bridges have shown great promise in eliminating corrosion : concerns and meeting (or exceeding) FHWAs goal of 100-year life spans for bridges. While FRP bridges are cost-effective in ...

Repair and retrofit of concrete bridge girders using hybrid FRP sheets.

DOT National Transportation Integrated Search

2012-02-01

The use of carbon fibers (CF) and glass fibers (GF) were combined to strengthen potentially non-ductile flexural : members. Based on tension tests of fiber-reinforced polymer (FRP) rovings and sheets, as well as theoretical : research on hybrid FRP, ...

Investigation of mRNA expression for secreted frizzled-related protein 2 (sFRP2) in chick embryos.

PubMed

Lin, Chung-Tien; Lin, Yu-Ting; Kuo, Tzong-Fu

2007-08-01

The roles of secreted frizzled-related protein 2 (sFRP2) in organ development of vertebrate animals are not well understood. We investigated expression of sFRP2 during embryogenesis of Arbor Acre broiler chicken eggs. Expression of sFRP2 was detected in the folds and lateral layer of developing brains. The sFRP2 signals in the developing eye were marked as a circle along the orbit. In younger embryos on days 3-6, the sFRP2 signals were consistent with growth of the sclerotome, suggesting that sFRP2 may be associated with somite development. Furthermore, with the exception of bones, sFRP2 mRNA was detectable in the interdigital tissue of embryos older than eight days as the limbs matured. This revealed that sFRP2 might play a role in myogenesis. In situ hybridization was also used to analyze the expression of sFRP2 in day 3-10 chick embryos. Signals were expressed in the gray matter of the developing brain coelom, including the optic lobe, metencephalon, myelencephalon, mesencephalon and diencephalon. The developing eyes contained an intercellular distribution of sFRP2 in the pigmented layer of the retina and photoreceptors. Furthermore, sFRP2 was expressed in the mantle layer of the neural tube and notochord. Based on these findings, it seems reasonable to suggest that sFRP2 may play an active role in embryogenesis, especially in development of the neural system, eyes, muscles and limbs.

Experimental evaluation and design of unfilled and concrete-filled FRP composite piles, task 2 - FRP composite pile driving at the Richmond-Dresden bridge over the Kennebec River.

DOT National Transportation Integrated Search

2014-01-01

The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP : composite piles for load-bearing in bridges. This report covers Task 2, FRP Composite Pile Driving at the : Richmond-Dresden Bridge over ...

Investigation of rectangular concrete columns reinforced or prestressed with fiber reinforced polymer (FRP) bars or tendons

NASA Astrophysics Data System (ADS)

Choo, Ching Chiaw

Fiber reinforced polymer (FRP) composites have been increasingly used in concrete construction. This research focused on the behavior of concrete columns reinforced with FRP bars, or prestressed with FRP tendons. The methodology was based the ultimate strength approach where stress and strain compatibility conditions and material constitutive laws were applied. Axial strength-moment (P-M) interaction relations of reinforced or prestressed concrete columns with FRP, a linearly-elastic material, were examined. The analytical results identified the possibility of premature compression and/or brittle-tension failure occurring in FRP reinforced and prestressed concrete columns where sudden and explosive type failures were expected. These failures were related to the rupture of FRP rebars or tendons in compression and/or in tension prior to concrete reaching its ultimate strain and strength. The study also concluded that brittle-tension failure was more likely to occur due to the low ultimate tensile strain of FRP bars or tendons as compared to steel. In addition, the failures were more prevalent when long term effects such as creep and shrinkage of concrete, and creep rupture of FRP were considered. Barring FRP failure, concrete columns reinforced with FRP, in some instances, gained significant moment resistance. As expected the strength interaction of slender steel or FRP reinforced concrete columns were dependent more on column length rather than material differences between steel and FRP. Current ACI minimum reinforcement ratio for steel (rhomin) reinforced concrete columns may not be adequate for use in FRP reinforced concrete columns. Design aids were developed in this study to determine the minimum reinforcement ratio (rhof,min) required for rectangular reinforced concrete columns by averting brittle-tension failure to a failure controlled by concrete crushing which in nature was a less catastrophic and more gradual type failure. The proposed method using rhof

Nonlinear behaviors of FRP-wrapped tall trees subjected to high wind loads

NASA Astrophysics Data System (ADS)

Kang, J.; Yi, Z. Z.; Choi, S. G.

2017-12-01

This study investigated the mechanical stability of historical tall trees wrapped with fiber-reinforced polymer (FRP) laminates using finite element (FE) analysis. High wind loads are considered as external loading conditions as they are one of the major threats on the structural stability of tall old trees. There have been several traditional practices to enhance the stability of tall trees exposed to high windstorms such as tree supporters and anchorages. They, however, have been sometimes causing negative effects with their misuses as the application guidelines for those methods were not adequately studied or documented. Furthermore, the oldest known trees in the country should be protected from the damage of external surface as well as ruin of the landscape. The objective of this study was to evaluate the structural effects of FRP wraps applied to tall trees subjected to high wind loads. The anisotropic material properties of wood and FRP laminates were considered in the analysis in addition to geometrically nonlinear behaviors. This study revealed that FRP wrapping for tall trees could effectively reduce the deflections and maximum stresses of trees, which results in the enhanced stability of tall trees. The optimum geometry and thicknesses of FRP wraps proposed in this study would provide fundemental guidelines for designing and constructing the application of innovative FRP wraps on tall trees, which are structurally unstable or should be preserved nationally and historically.

Flexural behaviour of RCC beams with externally bonded FRP

NASA Astrophysics Data System (ADS)

Vignesh, S. Arun; Sumathi, A.; Saravana Raja Mohan, K.

2017-07-01

The increasing use of carbon and glass fibre reinforced polymer (FRP) sheets for strengthening existing reinforced concrete beams has generated considerable interest in understanding the behavior of the FRP sheets when subjected to bending. The study on flexure includes various parameters like percentage of increase in strength of the member due to the externally bonded Fiber reinforced polymer, examining the crack patterns, reasons of debonding of the fibre from the structure, scaling, convenience of using the fibres, cost effectiveness etc. The present work aims to study experimentally about the reasons behind the failure due to flexure of an EB-FRP concrete beam by studying the various parameters. Deflection control may become as important as flexural strength for the design of FRPreinforced concrete structures. A numerical model is created using FEM software and the results are compared with that of the experiment.

Design and construction guidelines for strengthening bridges using fiber reinforced polymers (FRP).

DOT National Transportation Integrated Search

2014-09-01

This research concerns the development of guidelines : for the design and use of externally-bonded FRP : strengthening systems on bridges in Michigan. Si : x representative international FRP-related guidelines : were analyzed and compared for applica...

Pathfinder Rover, Airbags, & Martian Terrain

NASA Image and Video Library

1997-07-05

This is one of the first pictures taken by the camera on the Mars Pathfinder lander shortly after its touchdown at 10:07 AM Pacific Daylight Time on July 4, 1997. The small rover, named Sojourner, is seen in the foreground in its position on a solar panel of the lander. The white material on either side of the rover is part of the deflated airbag system used to absorb the shock of the landing. Between the rover and the horizon is the rock-strewn martian surface. Two hills are seen in the right distance, profiled against the light brown sky. http://photojournal.jpl.nasa.gov/catalog/PIA00611

Repair & Strengthening of Distressed/Damaged Ends of Prestressed Beams with FRP Composites

DOT National Transportation Integrated Search

2018-02-01

Over the past few decades, fiber reinforced polymer (FRP) composites have emerged as a lightweight and efficient material used for the repair and retrofit of concrete infrastructures. FRP can be applied to concrete as either externally bonded laminat...

Repairing/strengthening of bridges with post-tensioned FRP strands and performance evaluation.

DOT National Transportation Integrated Search

2008-06-01

The proposed project is to take advantage of some new developments in bridge engineering to apply fiber reinforced polymers (FRP) post-tensioning strands on a selected structure. The use of externally post-tensioned FRP strands to repair/strengthen b...

Concrete Open-Wall Systems Wrapped with FRP under Torsional Loads

PubMed Central

Mancusi, Geminiano; Feo, Luciano; Berardi, Valentino P.

2012-01-01

The static behavior of reinforced concrete (RC) beams plated with layers of fiber-reinforced composite material (FRP) is widely investigated in current literature, which deals with both its numerical modeling as well as experiments. Scientific interest in this topic is explained by the increasing widespread use of composite materials in retrofitting techniques, as well as the consolidation and upgrading of existing reinforced concrete elements to new service conditions. The effectiveness of these techniques is typically influenced by the debonding of the FRP at the interface with concrete, where the transfer of stresses occurs from one element (RC member) to the other (FRP strengthening). In fact, the activation of the well-known premature failure modes can be regarded as a consequence of high peak values of the interfacial interactions. Until now, typical applications of FRP structural plating have included cases of flexural or shear-flexural strengthening. Within this context, the present study aims at extending the investigation to the case of wall-systems with open cross-section under torsional loads. It includes the results of some numerical analyses carried out by means of a finite element approximation.

Small female head and neck interaction with a deploying side airbag.

PubMed

Duma, Stefan M; Crandall, Jeff R; Rudd, Rodney W; Kent, Richard W

2003-09-01

This paper presents dummy and cadaver experiments designed to investigate the injury potential of an out-of-position small female head and neck from a deploying side airbag. Seat-mounted, thoracic-type, side airbags were selected for this study to represent those currently available on selected luxury automobiles. A computer simulation program was used to identify the worst case loading position for the small female head and neck. Once the initial position was identified, experiments were performed with the Hybrid III 5th percentile dummy and three small female cadavers, using three different inflators. Peak head center of gravity (CG) accelerations for the dummy ranged from 71x g to 154 x g, and were greater than cadaver values, which ranged from 68 x g to 103 x g. Peak neck tension as measured at the upper load cell of the dummy increased with inflator aggressivity from 992 to 1670N. A conservative modification of the US National Highway Traffic Safety Administration's (NHTSA's) N(ij) proposed neck injury criteria, which combines neck tension and bending, was used. All values were well below the 1.0 injury threshold for the dummy and suggested a very low possibility of neck injury. In agreement with this prediction, no injuries were observed. Even in a worst case position, small females are at low risk of head or neck injuries under loading from these thoracic-type airbags; however, injury risk increases with increasing inflator aggressivity.

HP3 on ExoMars - Cutting airbag cloths with the sharp tip of a mechanical mole

NASA Astrophysics Data System (ADS)

Krause, C.; Izzo, M.; Re, E.; Mehls, C.; Richter, L.; Coste, P.

2009-04-01

The HP3 - Heat Flow and Physical Properties Package - is planned to be one of the Humboldt lander-based instruments on the ESA ExoMars mission. HP3 will allow the measurement of the subsurface temperature gradient and physical as well as thermophysical properties of the subsurface regolith of Mars down to a depth of 5 meters. From these measurements, the planetary heat flux can be inferred. The HP³ instrument package consists of a mole trailing a package of thermal and electrical sensors into the regolith. Beside the payload elements Thermal Excitation and Measurement Suite and a Permittivity Probe the HP3 experiment includes sensors to detect the forward motion and the tilt of the HP3 payload compartment. The HP3 experiment will be integrated into the lander platform of the ExoMars mission. The original accommodation featured a deployment device or a robotic arm to place HP3 onto the soil outside the deflated lander airbags. To avoid adding such deployment devices, it was suggested that the HP3 mole should be capable of piercing the airbags under the lander. The ExoMars lander airbag is made of 4 Kevlar layers (2 abrasive and 2 bladders). A double fold of the airbag (a worst case) would represent a pile of 12 layers. An exploratory study has examined the possibility of piercing airbag cloths by adding sharp cutting blades on the tip of a penetrating mole. In the experimental setup representative layers were laid over a Mars soil simulant. Initial tests used a hammer-driven cutting tip and had moderate to poor results. More representative tests used a prototype of the HP3 mole and were fully successful: the default 4 layer configuration was pierced as well as the 12 layer configuration, the latter one within 3 hours and about 3000 mole strokes This improved behaviour is attributed to the use of representative test hardware where guidance and suppression of mole recoil were concerned. The presentation will provide an explanation of the technical requirements on

Push-out tests and evaluation of FRP perfobond rib shear connectors performance

NASA Astrophysics Data System (ADS)

Kolpasky, Ludvik; Ryjacek, Pavel

2017-09-01

The behavioural characteristics of FRP (fibre-reinforced polymer) perfobond rib shear connector was examined through push-out tests in order to verify the applicability for pedestrian bridge structure. The aim of this study is to determine interaction between high performance concrete slab and handmade FRP plate which represent web of the composite beam. Combination of these modern materials leads to structural system with both great load bearing capacity and also sufficient flexural stiffness of the composite element. Openings cut into the GFRP plate at a variable spacing allow GFRP reinforcement bars to be inserted to act as shear studs. Hand lay-up process can increase suitable properties of FRP for connection by perfobond rib shear connectors. In this study, three push-out tests on fiber-reinforced polymer were performed to investigate their shear behaviour. The results of the push-out tests on FRP perfobond rib shear connector indicates great promise for application in full scale structures.

A model for predicting the shear bearing capacity of FRP-strengthened beams

NASA Astrophysics Data System (ADS)

Sas, G.; Carolin, A.; Täljsten, B.

2008-05-01

The shear failure of reinforced concrete beams needs more attention than the bending failure since no or only small warning precedes the failure. For this reason, it is of utmost importance to understand the shear bearing capacity and also to be able to undertake significant rehabilitation work if necessary. In this paper, a design model for the shear strengthening of concrete beams by using fiber-reinforced polymers (FRP) is presented, and the limitations of the truss model analogy are highlighted. The fracture mechanics approach is used in analyzing the bond behavior between the FRP composites and concrete. The fracture energy of concrete and the axial rigidity of the FRP are considered to be the most important parameters. The effective strain in the FRP when the debonding occurs is determined. The limitations of the anchorage length over the cross section are analyzed. A simple iterative design method for the shear debonding is finally proposed.

Dynamic response of RC beams strengthened with near surface mounted Carbon-FRP rods subjected to damage

NASA Astrophysics Data System (ADS)

Capozucca, R.; Blasi, M. G.; Corina, V.

2015-07-01

Near surface mounted (NSM) technique with fiber reinforced polymer (FRP) is becoming a common method in the strengthening of concrete beams. The availability of NSM FRP technique depends on many factors linked to materials and geometry - dimensions of the rods used, type of FRP material employed, rods’ surface configuration, groove size - and to adhesion between concrete and FRP rods. In this paper detection of damage is investigated measuring the natural frequency values of beam in the case of free-free ends. Damage was due both to reduction of adhesion between concrete and carbon-FRP rectangular and circular rods and cracking of concrete under static bending tests on beams. Comparison between experimental and theoretical frequency values evaluating frequency changes due to damage permits to monitor actual behaviour of RC beams strengthened by NSM CFRP rods.

Non-linear heterogeneous FE approach for FRP strengthened masonry arches

NASA Astrophysics Data System (ADS)

Bertolesi, Elisa; Milani, Gabriele; Fedele, Roberto

2015-12-01

A fast and reliable non-linear heterogeneous FE approach specifically conceived for the analysis of FRP-reinforced masonry arches is presented. The approach proposed relies into the reduction of mortar joints to interfaces exhibiting a non-linear holonomic behavior, with a discretization of bricks by means of four-noded elastic elements. The FRP reinforcement is modeled by means of truss elements with elastic-brittle behavior, where the peak tensile strength is estimated by means of a consolidated approach provided by the Italian guidelines CNR-DT200 on masonry strengthening with fiber materials, where the delamination of the strip from the support is taken into account. The model is validated against some recent experimental results relying into circular masonry arches reinforced at both the intrados and the extrados. Some sensitivity analyses are conducted varying the peak tensile strength of the trusses representing the FRP reinforcement.

The impact of airbags and seat belts on the incidence and severity of maxillofacial injuries in automobile accidents in New York State.

PubMed

Mouzakes, J; Koltai, P J; Kuhar, S; Bernstein, D S; Wing, P; Salsberg, E

2001-10-01

To evaluate the effect driver-side and passenger-side airbags have had on the incidence and severity of maxillofacial trauma in victims of automobile accidents. Retrospective analysis of all automobile (passenger cars and light trucks) accidents reported in 1994. New York State. Of the 595910 individuals involved in motor vehicle accidents in New York in 1994, 377054 individuals were initially selected from accidents involving cars and light trucks. Of this subset, 164238 drivers and 62755 right front passengers were selected for analysis. Each case is described in a single record with approximately 100 variables describing the accident, eg, vehicle, safety equipment installed and utilized or deployed, occupant position, patient demographics, International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnoses, and procedural treatments rendered. A maxillofacial trauma severity scale was devised, based on the ICD-9-CM diagnoses. Individuals using airbags and seat belts sustained facial injuries at a rate of 1 in 449, compared with a rate of 1 in 40 for individuals who did not use seat belts or airbags (P<.001). Those using airbags alone sustained facial injuries at the intermediate rate of 1 in 148, and victims using seat belts without airbags demonstrated an injury rate of 1 in 217 (P<.001). Use of driver-side airbags, when combined with use of seat belts, has resulted in a decrease in the incidence and severity of maxillofacial trauma.

The engineering of construction specifications for externally bonded FRP composites

NASA Astrophysics Data System (ADS)

Yang, Xinbao

This dissertation, consisting of six technical papers, presents the results of research on the theme of developing engineering and the construction specifications for externally bonded FRP composites. For particular, the work focuses on three critical aspects of the performance of FRP systems: fiber misalignment, corner radius, and lap splice length. Based on both experimental and theoretical investigations, the main contribution of this work is the development of recommendations on fiber misalignment limit, minimum corner radius, lap splice length to be used as guidance in the construction practice of FRP strengthening of concrete structures. The first three papers focus on the strength and stiffness degradation of CFRP laminates from fiber misalignment. It was concluded that misalignment affects strength more than stiffness. In practice, when all fibers in a laminate can be regarded as through fibers, it is recommended to use a reduction factor for strength and no reduction factor for stiffness to account for fiber misalignment. Findings from concrete beams strengthened with misaligned CFRP laminates verified these recommendations. The fourth and fifth papers investigate the effect of corner radius on the mechanical properties of CFRP laminates wrapped around a rectangular cross section. A unique reusable test device was fabricated to determine fiber stress and radial stress of CFRP laminates with different corner radii. Comparison performed with finite element analyses shows that the test method and the reusable device were viable and the stress concentration needs to be considered in FRP laminate wrapped corners. A minimum of 1.0 in. corner radius was recommended for practice. The sixth paper summarizes the research on the lap splice length of FRP laminates under static and repeated loads. Although a lap splice length of 1.5 in. is sufficient for CFRP laminates to develop the ultimate static tensile strength, a minimum of 4.0 in. is recommended in order to

Blast Design of Reinforced Concrete and Masonry Components Retrofitted with FRP

DTIC Science & Technology

2010-07-01

1 BLAST DESIGN OF REINFORCED CONCRETE AND MASONRY COMPONENTS RETROFITTED WITH FRP Marlon L. Bazan, Ph.D. and Charles J. Oswald, P.E., Ph.D...as an alternative to traditional methods for strengthening and retrofitting concrete and masonry structures to resist blast loads. The development...and experimental validation of a methodology for modeling the response of blast loaded concrete and masonry structural components retrofitted with FRP

Reliability model for ductile hybrid FRP rebar using randomly dispersed chopped fibers

NASA Astrophysics Data System (ADS)

Behnam, Bashar Ramzi

Fiber reinforced polymer composites or simply FRP composites have become more attractive to civil engineers in the last two decades due to their unique mechanical properties. However, there are many obstacles such as low elasticity modulus, non-ductile behavior, high cost of the fibers, high manufacturing costs, and absence of rigorous characterization of the uncertainties of the mechanical properties that restrict the use of these composites. However, when FRP composites are used to develop reinforcing rebars in concrete structural members to replace the conventional steel, a huge benefit can be achieved since FRP materials don't corrode. Two FRP rebar models are proposed that make use of multiple types of fibers to achieve ductility, and chopped fibers are used to reduce the manufacturing costs. In order to reach the most optimum fractional volume of each type of fiber, to minimize the cost of the proposed rebars, and to achieve a safe design by considering uncertainties in the materials and geometry of sections, appropriate material resistance factors have been developed, and a Reliability Based Design Optimization (RBDO), has been conducted for the proposed schemes.

A Review on Strengthening Steel Beams Using FRP under Fatigue

PubMed Central

Jumaat, Mohd Zamin; Ramli Sulong, N. H.

2014-01-01

In recent decades, the application of fibre-reinforced polymer (FRP) composites for strengthening structural elements has become an efficient option to meet the increased cyclic loads or repair due to corrosion or fatigue cracking. Hence, the objective of this study is to explore the existing FRP reinforcing techniques to care for fatigue damaged structural steel elements. This study covers the surface treatment techniques, adhesive curing, and support conditions under cyclic loading including fatigue performance, crack propagation, and failure modes with finite element (FE) simulation of the steel bridge girders and structural elements. FRP strengthening composites delay initial cracking, reduce the crack growth rate, extend the fatigue life, and decrease the stiffness decay with residual deflection. Prestressed carbon fibre-reinforced polymer (CFRP) is the best strengthening option. End anchorage prevents debonding of the CRRP strips at the beam ends by reducing the local interfacial shear and peel stresses. Hybrid-joint, nanoadhesive, and carbon-flex can also be attractive for strengthening systems. PMID:25243221

A review on strengthening steel beams using FRP under fatigue.

PubMed

Kamruzzaman, Mohamed; Jumaat, Mohd Zamin; Sulong, N H Ramli; Islam, A B M Saiful

2014-01-01

In recent decades, the application of fibre-reinforced polymer (FRP) composites for strengthening structural elements has become an efficient option to meet the increased cyclic loads or repair due to corrosion or fatigue cracking. Hence, the objective of this study is to explore the existing FRP reinforcing techniques to care for fatigue damaged structural steel elements. This study covers the surface treatment techniques, adhesive curing, and support conditions under cyclic loading including fatigue performance, crack propagation, and failure modes with finite element (FE) simulation of the steel bridge girders and structural elements. FRP strengthening composites delay initial cracking, reduce the crack growth rate, extend the fatigue life, and decrease the stiffness decay with residual deflection. Prestressed carbon fibre-reinforced polymer (CFRP) is the best strengthening option. End anchorage prevents debonding of the CRRP strips at the beam ends by reducing the local interfacial shear and peel stresses. Hybrid-joint, nanoadhesive, and carbon-flex can also be attractive for strengthening systems.

Review of Punching Shear Behaviour of Flat Slabs Reinforced with FRP Bars

NASA Astrophysics Data System (ADS)

Mohamed, Osama A.; Khattab, Rania

2017-10-01

Using Fibre Reinforced Polymer (FRP) bars to reinforce two-way concrete slabs can extend the service life, reduce maintenance cost and improve-life cycle cost efficiency. FRP reinforcing bars are more environmentally friendly alternatives to traditional reinforcing steel. Shear behaviour of reinforced concrete structural members is a complex phenomenon that relies on the development of internal load-carrying mechanisms, the magnitude and combination of which is still a subject of research. Many building codes and design standards provide design formulas for estimation of punching shear capacity of FRP reinforced flat slabs. Building code formulas take into account the effects of the axial stiffness of main reinforcement bars, the ratio of the perimeter of the critical section to the slab effective depth, and the slab thickness on the punching shear capacity of two-way slabs reinforced with FRP bars or grids. The goal of this paper is to compare experimental data published in the literature to the equations offered by building codes for the estimation of punching shear capacity of concrete flat slabs reinforced with FRP bars. Emphasis in this paper is on two North American codes, namely, ACI 440.1R-15 and CSA S806-12. The experimental data covered in this paper include flat slabs reinforced with GFRP, BFRP, and CFRP bars. Both ACI 440.1R-15 and CSA S806-12 are shown to be in good agreement with test results in terms of predicting the punching shear capacity.

Nonlinear micromechanics-based finite element analysis of the interfacial behaviour of FRP-strengthened reinforced concrete beams

NASA Astrophysics Data System (ADS)

Abd El Baky, Hussien

This research work is devoted to theoretical and numerical studies on the flexural behaviour of FRP-strengthened concrete beams. The objectives of this research are to extend and generalize the results of simple experiments, to recommend new design guidelines based on accurate numerical tools, and to enhance our comprehension of the bond performance of such beams. These numerical tools can be exploited to bridge the existing gaps in the development of analysis and modelling approaches that can predict the behaviour of FRP-strengthened concrete beams. The research effort here begins with the formulation of a concrete model and development of FRP/concrete interface constitutive laws, followed by finite element simulations for beams strengthened in flexure. Finally, a statistical analysis is carried out taking the advantage of the aforesaid numerical tools to propose design guidelines. In this dissertation, an alternative incremental formulation of the M4 microplane model is proposed to overcome the computational complexities associated with the original formulation. Through a number of numerical applications, this incremental formulation is shown to be equivalent to the original M4 model. To assess the computational efficiency of the incremental formulation, the "arc-length" numerical technique is also considered and implemented in the original Bazant et al. [2000] M4 formulation. Finally, the M4 microplane concrete model is coded in FORTRAN and implemented as a user-defined subroutine into the commercial software package ADINA, Version 8.4. Then this subroutine is used with the finite element package to analyze various applications involving FRP strengthening. In the first application a nonlinear micromechanics-based finite element analysis is performed to investigate the interfacial behaviour of FRP/concrete joints subjected to direct shear loadings. The intention of this part is to develop a reliable bond--slip model for the FRP/concrete interface. The bond

Comparing Driver Frontal Mortality in Vehicles with Redesigned and Older-Design Front Airbags

PubMed Central

Braver, Elisa R.; Kyrychenko, Sergey Y.; Ferguson, Susan A.

2004-01-01

In 1997, the National Highway Traffic Safety Administration amended its requirements for frontal crash performance under Federal Motor Vehicle Safety Standard 208 to temporarily allow 30 mph (48 kph) sled tests with unbelted dummies as an alternative to 30 mph head-on rigid-barrier vehicle tests. This change permitted automakers to reduce airbag inflation forces so that they would be less likely to injure occupants who are close to airbags when they first deploy. Most vehicle models were sled-certified starting in model year 1998. Airbag-related deaths have decreased since 1997; however, controversy persists about whether reduced inflation forces might be decreasing protection for some occupants in high-severity frontal crashes. To examine the effects of the regulatory changes, this study computed rate ratios (RR) and 95 percent confidence intervals (95% CI) for passenger vehicle driver deaths per vehicle registration during 2000–02 at principal impact points of 12 o’clock for 1998–99 model year vehicles relative to 1997 models. Passenger vehicles included in the study had both driver and passenger front airbags, had the same essential designs during the 1997–99 model years, and had been sled-certified for drivers throughout model years 1998 and 1999. An adjustment was made for the higher annual mileage of newer vehicles. Findings were that the effect of the regulatory change varied by vehicle type. For cars, sport utility vehicles, and minivans combined, there was an 11 percent decrease in fatality risk in frontal crashes after changing to sled certification (RR=0.89; 95% CI=0.82–0.96). Among pickups, however, estimated frontal fatality risk increased 35 percent (RR=1.35; 95% CI=1.12–1.62). For a broad range of frontal crashes (11, 12, and 1 o’clock combined), the results indicated a modest net benefit of the regulatory change across all vehicle types and driver characteristics. However, the contrary finding for pickups needs to be researched further

Comparing driver frontal mortality in vehicles with redesigned and older-design front airbags.

PubMed

Braver, Elisa R; Kyrychenko, Sergey Y; Ferguson, Susan A

2004-01-01

In 1997, the National Highway Traffic Safety Administration amended its requirements for frontal crash performance under Federal Motor Vehicle Safety Standard 208 to temporarily allow 30 mph (48 kph) sled tests with unbelted dummies as an alternative to 30 mph head-on rigid-barrier vehicle tests. This change permitted automakers to reduce airbag inflation forces so that they would be less likely to injure occupants who are close to airbags when they first deploy. Most vehicle models were sled-certified starting in model year 1998. Airbag-related deaths have decreased since 1997; however, controversy persists about whether reduced inflation forces might be decreasing protection for some occupants in high-severity frontal crashes. To examine the effects of the regulatory changes, this study computed rate ratios (RR) and 95 percent confidence intervals (95% CI) for passenger vehicle driver deaths per vehicle registration during 2000-02 at principal impact points of 12 o'clock for 1998-99 model year vehicles relative to 1997 models. Passenger vehicles included in the study had both driver and passenger front airbags, had the same essential designs during the 1997-99 model years, and had been sled-certified for drivers throughout model years 1998 and 1999. An adjustment was made for the higher annual mileage of newer vehicles. Findings were that the effect of the regulatory change varied by vehicle type. For cars, sport utility vehicles, and minivans combined, there was an 11 percent decrease in fatality risk in frontal crashes after changing to sled certification (RR=0.89; 95% CI=0.82-0.96). Among pickups, however, estimated frontal fatality risk increased 35 percent (RR=1.35; 95% CI=1.12-1.62). For a broad range of frontal crashes (11, 12, and 1 o'clock combined), the results indicated a modest net benefit of the regulatory change across all vehicle types and driver characteristics. However, the contrary finding for pickups needs to be researched further.

Development of advanced grid stiffened (AGS) fiber reinforced polymer (FRP) tube-encased concrete columns.

DOT National Transportation Integrated Search

2013-03-01

In this project, a new type of confining device, a latticework of interlacing fiber reinforced polymer (FRP) ribs that are jacketed by a FRP skin, is proposed, manufactured, tested, and modeled to encase concrete cylinders. This systematic study incl...

SOFTWARE ENGINEERING INSTITUTE (SEI)

EPA Science Inventory

The Software Engineering Institute (SEI) is a federally funded research and development center established in 1984 by the U.S. Department of Defense and operated by Carnegie Mellon University. SEI has a broad charter to provide leadership in the practice of software engineering t...

Third SEI Technical Interchange: Proceedings

NASA Technical Reports Server (NTRS)

1992-01-01

Given here are the proceedings of the 3rd Space Exploration Initiative (SEI) Technical Interchange. Topics covered include the First Lunar Outpost (FLO), the Lunar Resource Mapper, lunar rovers, lunar habitat concepts, lunar shelter construction analysis, thermoelectric nuclear power systems for SEI, cryogenic storage, a space network for lunar communications, the moon as a solar power satellite, and off-the-shelf avionics for future SEI missions.

Bridge-in-a-Backpack(TM). Task 7 : investigation of damage and repairs for concrete filled FRP tubular arches.

DOT National Transportation Integrated Search

2015-04-01

This report includes fulfillment of Task 7 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. : Damage due to impact of the FRP shell of the concrete filled FRP tubular arch bridges has been and stil...

Validation of FRP Matting Requirements

DTIC Science & Technology

2016-08-01

airfield pavements using crushed stone. A side-by-side comparison between FRP and folded fiberglass matting (FFM) was performed on simulated small...medium, and large craters in Portland cement concrete and asphalt concrete pavements . The demonstration took place at the Silver Flag Exercise Site...report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. DESTROY THIS

Modeling delamination of FRP laminates under low velocity impact

NASA Astrophysics Data System (ADS)

Jiang, Z.; Wen, H. M.; Ren, S. L.

2017-09-01

Fiber reinforced plastic laminates (FRP) have been increasingly used in various engineering such as aeronautics, astronautics, transportation, naval architecture and their impact response and failure are a major concern in academic community. A new numerical model is suggested for fiber reinforced plastic composites. The model considers that FRP laminates has been constituted by unidirectional laminated plates with adhesive layers. A modified adhesive layer damage model that considering strain rate effects is incorporated into the ABAQUS / EXPLICIT finite element program by the user-defined material subroutine VUMAT. It transpires that the present model predicted delamination is in good agreement with the experimental results for low velocity impact.

Hybrid FRP-concrete bridge deck system final report II : long term performance of hybrid FRP-concrete bridge deck system.

DOT National Transportation Integrated Search

2009-06-01

This report describes the investigation of the long term structural performance of a : hybrid FRP-concrete (HFRPC) bridge deck on steel girders. The study aimed at : assessing three long term aspects pertaining to the HFRPC bridge deck: (1) creep : c...

Highly accelerated lifetime for externally applied bond critical fiber-reinforced polymer (FRP) infrastructure materials : [summary].

DOT National Transportation Integrated Search

2014-03-01

The Florida Department of Transportation (FDOT) uses fiber-reinforced polymer (FRP) composites to repair bridges and strengthen bridge decks. Proven mechanical characteristics make FRP composites cost-effective in extending the life span of bridges o...

Distributed Long-Gauge Optical Fiber Sensors Based Self-Sensing FRP Bar for Concrete Structure

PubMed Central

Tang, Yongsheng; Wu, Zhishen

2016-01-01

Brillouin scattering-based distributed optical fiber (OF) sensing technique presents advantages for concrete structure monitoring. However, the existence of spatial resolution greatly decreases strain measurement accuracy especially around cracks. Meanwhile, the brittle feature of OF also hinders its further application. In this paper, the distributed OF sensor was firstly proposed as long-gauge sensor to improve strain measurement accuracy. Then, a new type of self-sensing fiber reinforced polymer (FRP) bar was developed by embedding the packaged long-gauge OF sensors into FRP bar, followed by experimental studies on strain sensing, temperature sensing and basic mechanical properties. The results confirmed the superior strain sensing properties, namely satisfied accuracy, repeatability and linearity, as well as excellent mechanical performance. At the same time, the temperature sensing property was not influenced by the long-gauge package, making temperature compensation easy. Furthermore, the bonding performance between self-sensing FRP bar and concrete was investigated to study its influence on the sensing. Lastly, the sensing performance was further verified with static experiments of concrete beam reinforced with the proposed self-sensing FRP bar. Therefore, the self-sensing FRP bar has potential applications for long-term structural health monitoring (SHM) as embedded sensors as well as reinforcing materials for concrete structures. PMID:26927110

An investigation into the impact of cryogenic environment on mechanical stresses in FRP composites

NASA Astrophysics Data System (ADS)

Fifo, O.; Basu, B.

2015-07-01

Fibre reinforced polymer (FRP) composites are fast becoming a highly utilised engineering material for high performance applications due to their light weight and high strength. Carbon fibre and other high strength fibres are commonly used in design of aerospace structures, wind turbine blades, etc. and potentially for propellant tanks of launch vehicles. For the aforementioned fields of application, stability of the material is essential over a wide range of temperature particularly for structures in hostile environments. Many studies have been conducted, experimentally, over the last decade to investigate the mechanical behaviour of FRP materials at varying subzero temperature. Likewise, tests on aging and cycling effect (room to low temperature) on the mechanical response of FRP have been reported. However, a relatively lesser focused area has been the mechanical behaviour of FRP composites under cryogenic environment. This article reports a finite element method of investigating the changes in the mechanical characteristics of an FRP material when temperature based analysis falls below zero. The simulated tests are carried out using a finite element package with close material properties used in the cited literatures. Tensile test was conducted and the results indicate that the mechanical responses agree with those reported in the literature sited.

Distributed Long-Gauge Optical Fiber Sensors Based Self-Sensing FRP Bar for Concrete Structure.

PubMed

Tang, Yongsheng; Wu, Zhishen

2016-02-25

Brillouin scattering-based distributed optical fiber (OF) sensing technique presents advantages for concrete structure monitoring. However, the existence of spatial resolution greatly decreases strain measurement accuracy especially around cracks. Meanwhile, the brittle feature of OF also hinders its further application. In this paper, the distributed OF sensor was firstly proposed as long-gauge sensor to improve strain measurement accuracy. Then, a new type of self-sensing fiber reinforced polymer (FRP) bar was developed by embedding the packaged long-gauge OF sensors into FRP bar, followed by experimental studies on strain sensing, temperature sensing and basic mechanical properties. The results confirmed the superior strain sensing properties, namely satisfied accuracy, repeatability and linearity, as well as excellent mechanical performance. At the same time, the temperature sensing property was not influenced by the long-gauge package, making temperature compensation easy. Furthermore, the bonding performance between self-sensing FRP bar and concrete was investigated to study its influence on the sensing. Lastly, the sensing performance was further verified with static experiments of concrete beam reinforced with the proposed self-sensing FRP bar. Therefore, the self-sensing FRP bar has potential applications for long-term structural health monitoring (SHM) as embedded sensors as well as reinforcing materials for concrete structures.

Constitutive Behavior and Finite Element Analysis of FRP Composite and Concrete Members.

PubMed

Ann, Ki Yong; Cho, Chang-Geun

2013-09-10

The present study concerns compressive and flexural constitutive models incorporated into an isoparametric beam finite element scheme for fiber reinforced polymer (FRP) and concrete composites, using their multi-axial constitutive behavior. The constitutive behavior of concrete was treated in triaxial stress states as an orthotropic hypoelasticity-based formulation to determine the confinement effect of concrete from a three-dimensional failure surface in triaxial stress states. The constitutive behavior of the FRP composite was formulated from the two-dimensional classical lamination theory. To predict the flexural behavior of circular cross-section with FRP sheet and concrete composite, a layered discretization of cross-sections was incorporated into nonlinear isoparametric beam finite elements. The predicted constitutive behavior was validated by a comparison to available experimental results in the compressive and flexural beam loading test.

Constitutive Behavior and Finite Element Analysis of FRP Composite and Concrete Members

PubMed Central

Ann, Ki Yong; Cho, Chang-Geun

2013-01-01

The present study concerns compressive and flexural constitutive models incorporated into an isoparametric beam finite element scheme for fiber reinforced polymer (FRP) and concrete composites, using their multi-axial constitutive behavior. The constitutive behavior of concrete was treated in triaxial stress states as an orthotropic hypoelasticity-based formulation to determine the confinement effect of concrete from a three-dimensional failure surface in triaxial stress states. The constitutive behavior of the FRP composite was formulated from the two-dimensional classical lamination theory. To predict the flexural behavior of circular cross-section with FRP sheet and concrete composite, a layered discretization of cross-sections was incorporated into nonlinear isoparametric beam finite elements. The predicted constitutive behavior was validated by a comparison to available experimental results in the compressive and flexural beam loading test. PMID:28788312

76 FR 63316 - Prospective Grant of Exclusive License: Secreted Frizzled Related Protein-1 (sFRP-1) and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-12

... Exclusive License: Secreted Frizzled Related Protein-1 (sFRP-1) and derivatives thereof and their Use In... belonging to the patent families having HHS Reference Numbers E-160-1997/0,/1,/2 and/3; E-014-2000/0; and E... Related Protein-1 (sFRP-1). sFRP-1, also known as SARP-2 (Secreted Apoptosis Related Protein-2). The IP...

Development of Lateral Prestress in High-Strength Concrete-Filled FRP Tubes

NASA Astrophysics Data System (ADS)

Vincent, T.; Ozbakkaloglu, T.

2018-02-01

This paper reports on an experimental investigation into the axial and lateral strain development of fiber reinforced polymer (FRP) confined high-strength concrete (HSC) with prestressed FRP shells. A total of 24 aramid FRP (AFRP)-confined concrete specimens were manufactured as concrete-filled FRP tubes (CFFTs) with instrumentation to measure the strain variations during application of prestress, removal of end constraints and progressive prestress losses. Prestressed CFFT specimens were prepared with three different dose rates of expansive mineral admixture to create a range of lateral prestress applied to AFRP tubes manufactured with sheet thicknesses of 0.2 or 0.3 mm/ply and referred to as lightly- or well-confined, respectively. In addition to these three levels of prestress, non-prestressed companion specimens were manufactured and tested to determine baseline performance. The experimental results from this study indicate that lateral prestressing of CFFTs manufactured with HSC can be achieved by varying the expansive mineral admixture dose rate with a lateral prestress of up to 7.3 MPa recorded in this study. Significant strain variations were measured during removal of the end constraints with up to 700 microstrain recorded in the axial direction. Finally, the measurement of prestress losses for the month following prestress application revealed minimal progressive losses, with only 250 and 100 με recorded for the axial and hoop strains, respectively.

Investigating the Effects of Side Airbag Deployment in Real-World Crashes Using Crash Comparison Techniques

PubMed Central

Loftis, Kathryn L.; Weaver, Ashley A.; Stitzel, Joel D.

2011-01-01

The objective of this study was to investigate side airbag (SAB) deployment in near side crashes and compare injuries and contact points between occupants with and without SAB deployment. Using NASS 2000–2008 and selecting for near side cases, with PDOF ± 20 degrees from 90 or 270, for non-pregnant adult belted occupants, there were 20,253 (weighted) SAB deployments. NASS showed that SABs have been increasing within the fleet, comprising 2% of airbags in 2000 and increasing to 33% of airbags in 2008. To investigate deployed SABs, we developed a three-step methology to pair CIREN cases to study the effects of deployment on occupant outcome. The first step involved extracting near side impacts from CIREN with adult, non-pregnant occupants seated in row 1 (drivers or right front passengers). In the second step, each case was quantitatively compared to FMVSS 214 barrier test standards using a 6 point similarity scoring system. Cases scoring at least 3 points were then qualitatively analyzed and 33 pairs of cases of the same vehicle make/model but opposite SAB status were chosen. Occupants with deployed SAB had reduced occurrences and severity of head and face, neck and cervical spine, and thoracic injuries and fewer injurious contacts to side components including the door, a-pillar, and window sill. SAB deployment was statistically significant for reducing occupant MAIS and ISS and thorax airbags were statistically significant for reducing thoracic and neck/cervical spine injury severity. The average ISS with SAB deployment was 21, while the average ISS of those without was 33. This study establishes methods for performing comparisons between CIREN cases based on regulatory conditions and shows injury reduction in key body regions with SAB deployment. PMID:22105386

Design Optimization of Hybrid FRP/RC Bridge

NASA Astrophysics Data System (ADS)

Papapetrou, Vasileios S.; Tamijani, Ali Y.; Brown, Jeff; Kim, Daewon

2018-04-01

The hybrid bridge consists of a Reinforced Concrete (RC) slab supported by U-shaped Fiber Reinforced Polymer (FRP) girders. Previous studies on similar hybrid bridges constructed in the United States and Europe seem to substantiate these hybrid designs for lightweight, high strength, and durable highway bridge construction. In the current study, computational and optimization analyses were carried out to investigate six composite material systems consisting of E-glass and carbon fibers. Optimization constraints are determined by stress, deflection and manufacturing requirements. Finite Element Analysis (FEA) and optimization software were utilized, and a framework was developed to run the complete analyses in an automated fashion. Prior to that, FEA validation of previous studies on similar U-shaped FRP girders that were constructed in Poland and Texas is presented. A finer optimization analysis is performed for the case of the Texas hybrid bridge. The optimization outcome of the hybrid FRP/RC bridge shows the appropriate composite material selection and cross-section geometry that satisfies all the applicable Limit States (LS) and, at the same time, results in the lightest design. Critical limit states show that shear stress criteria determine the optimum design for bridge spans less than 15.24 m and deflection criteria controls for longer spans. Increased side wall thickness can reduce maximum observed shear stresses, but leads to a high weight penalty. A taller cross-section and a thicker girder base can efficiently lower the observed deflections and normal stresses. Finally, substantial weight savings can be achieved by the optimization framework if base and side-wall thickness are treated as independent variables.

Elimination of deck joints using a corrosion resistant FRP approach : LTRC technical summary report 443.

DOT National Transportation Integrated Search

2009-01-01

In the literature survey of fiber reinforced polymer (FRP) grid reinforced concrete : structures, a limited number of studies were found on FRP grid stiffened concrete slabs : in bridge deck applications and other non-structural applications in build...

Packing and deploying Soft Origami to and from cylindrical volumes with application to automotive airbags

PubMed Central

Nelson, Todd G.; Zimmerman, Trent K.; Fernelius, Janette D.; Magleby, Spencer P.; Howell, Larry L.

2016-01-01

Packing soft-sheet materials of approximately zero bending stiffness using Soft Origami (origami patterns applied to soft-sheet materials) into cylindrical volumes and their deployment via mechanisms or internal pressure (inflation) is of interest in fields including automobile airbags, deployable heart stents, inflatable space habitats, and dirigible and parachute packing. This paper explores twofold patterns, the ‘flasher’ and the ‘inverted-cone fold’, for packing soft-sheet materials into cylindrical volumes. Two initial packing methods and mechanisms are examined for each of the flasher and inverted-cone fold patterns. An application to driver’s side automobile airbags is performed, and deployment tests are completed to compare the influence of packing method and origami pattern on deployment performance. Following deployment tests, two additional packing methods for the inverted-cone fold pattern are explored and applied to automobile airbags. It is shown that modifying the packing method (using different methods to impose the same base pattern on the soft-sheet material) can lead to different deployment performance. In total, two origami patterns and six packing methods are examined, and the benefits of using Soft Origami patterns and packing methods are discussed. Soft Origami is presented as a viable method for efficiently packing soft-sheet materials into cylindrical volumes. PMID:27703707

Packing and deploying Soft Origami to and from cylindrical volumes with application to automotive airbags

NASA Astrophysics Data System (ADS)

Bruton, Jared T.; Nelson, Todd G.; Zimmerman, Trent K.; Fernelius, Janette D.; Magleby, Spencer P.; Howell, Larry L.

2016-09-01

Packing soft-sheet materials of approximately zero bending stiffness using Soft Origami (origami patterns applied to soft-sheet materials) into cylindrical volumes and their deployment via mechanisms or internal pressure (inflation) is of interest in fields including automobile airbags, deployable heart stents, inflatable space habitats, and dirigible and parachute packing. This paper explores twofold patterns, the `flasher' and the `inverted-cone fold', for packing soft-sheet materials into cylindrical volumes. Two initial packing methods and mechanisms are examined for each of the flasher and inverted-cone fold patterns. An application to driver's side automobile airbags is performed, and deployment tests are completed to compare the influence of packing method and origami pattern on deployment performance. Following deployment tests, two additional packing methods for the inverted-cone fold pattern are explored and applied to automobile airbags. It is shown that modifying the packing method (using different methods to impose the same base pattern on the soft-sheet material) can lead to different deployment performance. In total, two origami patterns and six packing methods are examined, and the benefits of using Soft Origami patterns and packing methods are discussed. Soft Origami is presented as a viable method for efficiently packing soft-sheet materials into cylindrical volumes.

Packing and deploying Soft Origami to and from cylindrical volumes with application to automotive airbags.

PubMed

Bruton, Jared T; Nelson, Todd G; Zimmerman, Trent K; Fernelius, Janette D; Magleby, Spencer P; Howell, Larry L

2016-09-01

Packing soft-sheet materials of approximately zero bending stiffness using Soft Origami (origami patterns applied to soft-sheet materials) into cylindrical volumes and their deployment via mechanisms or internal pressure (inflation) is of interest in fields including automobile airbags, deployable heart stents, inflatable space habitats, and dirigible and parachute packing. This paper explores twofold patterns, the 'flasher' and the 'inverted-cone fold', for packing soft-sheet materials into cylindrical volumes. Two initial packing methods and mechanisms are examined for each of the flasher and inverted-cone fold patterns. An application to driver's side automobile airbags is performed, and deployment tests are completed to compare the influence of packing method and origami pattern on deployment performance. Following deployment tests, two additional packing methods for the inverted-cone fold pattern are explored and applied to automobile airbags. It is shown that modifying the packing method (using different methods to impose the same base pattern on the soft-sheet material) can lead to different deployment performance. In total, two origami patterns and six packing methods are examined, and the benefits of using Soft Origami patterns and packing methods are discussed. Soft Origami is presented as a viable method for efficiently packing soft-sheet materials into cylindrical volumes.

Crack detection and fatigue related delamination in FRP composites applied to concrete

NASA Astrophysics Data System (ADS)

Brown, Jeff; Baker, Rebecca; Kallemeyn, Lisa; Zendler, Andrew

2008-03-01

Reinforced concrete beams are designed to allow minor concrete cracking in the tension zone. The severity of cracking in a beam element is a good indicator of how well a structure is performing and whether or not repairs are needed to prevent structural failure. FRP composites are commonly used to increase the flexural and shear capacity of RC beam elements, but one potential disadvantage of this method is that strengthened surfaces are no longer visible and cracks or delaminations that result from excessive loading or fatigue may go undetected. This research investigated thermal imaging techniques for detecting load induced cracking in the concrete substrate and delamination of FRP strengthening systems applied to reinforced concrete (RC). One small-scale RC beam (5 in. x 6 in. x 60 in.) was strengthened with FRP and loaded to failure monotonically. An infrared thermography inspection was performed after failure. A second strengthened beam was loaded cyclically for 1,750,000 cycles to investigate how fatigue might affect substrate cracking and delamination growth throughout the service-life of a repaired element. No changes were observed in the FRP bond during/after the cyclic loading. The thermal imaging component of this research included pixel normalization to enhance detectability and characterization of this specific type of damage.

Mechanical properties and aesthetics of FRP orthodontic wire fabricated by hot drawing.

PubMed

Imai, T; Watari, F; Yamagata, S; Kobayashi, M; Nagayama, K; Toyoizumi, Y; Nakamura, S

1998-12-01

The FRP wires 0.5 mm in diameter with a multiple fiber structure were fabricated by drawing the fiber polymer complex at 250 degrees C for an esthetic, transparent orthodontic wire. Biocompatible CaO-P2O5-SiO2-Al2O3 (CPSA) glass fibers of 8-20 microm in diameter were oriented unidirectionally in the longitudinal direction in PMMA matrix. The mechanical properties were investigated by 3-point flexural test. The FRP wire showed sufficient strength and a very good elastic recovery after deformation. Young's modulus and the flexural load at deflection 1 mm were nearly independent of the fiber diameter and linearly increased with the fiber fraction. The dependence on fiber fraction obeys well the rule of mixture. This FRP wire could cover the range of strength corresponding to the conventional metal orthodontic wires from Ni-Ti used in the initial stage of orthodontic treatments to Co-Cr used in the final stage by changing the volume ratio of glass fibers with the same external diameter. The estheticity in external appearance was excellent. Thus the new FRP wire can satisfy both mechanical properties necessary for an orthodontic wire and enough estheticity, which was not possible for the conventional metal wire.

LSA SAF Meteosat FRP products - Part 2: Evaluation and demonstration for use in the Copernicus Atmosphere Monitoring Service (CAMS)

NASA Astrophysics Data System (ADS)

Roberts, G.; Wooster, M. J.; Xu, W.; Freeborn, P. H.; Morcrette, J.-J.; Jones, L.; Benedetti, A.; Jiangping, H.; Fisher, D.; Kaiser, J. W.

2015-11-01

Characterising the dynamics of landscape-scale wildfires at very high temporal resolutions is best achieved using observations from Earth Observation (EO) sensors mounted onboard geostationary satellites. As a result, a number of operational active fire products have been developed from the data of such sensors. An example of which are the Fire Radiative Power (FRP) products, the FRP-PIXEL and FRP-GRID products, generated by the Land Surface Analysis Satellite Applications Facility (LSA SAF) from imagery collected by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard the Meteosat Second Generation (MSG) series of geostationary EO satellites. The processing chain developed to deliver these FRP products detects SEVIRI pixels containing actively burning fires and characterises their FRP output across four geographic regions covering Europe, part of South America and Northern and Southern Africa. The FRP-PIXEL product contains the highest spatial and temporal resolution FRP data set, whilst the FRP-GRID product contains a spatio-temporal summary that includes bias adjustments for cloud cover and the non-detection of low FRP fire pixels. Here we evaluate these two products against active fire data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) and compare the results to those for three alternative active fire products derived from SEVIRI imagery. The FRP-PIXEL product is shown to detect a substantially greater number of active fire pixels than do alternative SEVIRI-based products, and comparison to MODIS on a per-fire basis indicates a strong agreement and low bias in terms of FRP values. However, low FRP fire pixels remain undetected by SEVIRI, with errors of active fire pixel detection commission and omission compared to MODIS ranging between 9-13 % and 65-77 % respectively in Africa. Higher errors of omission result in greater underestimation of regional FRP totals relative to those derived from simultaneously collected MODIS

LSA SAF Meteosat FRP Products: Part 2 - Evaluation and demonstration of use in the Copernicus Atmosphere Monitoring Service (CAMS)

NASA Astrophysics Data System (ADS)

Roberts, G.; Wooster, M. J.; Xu, W.; Freeborn, P. H.; Morcrette, J.-J.; Jones, L.; Benedetti, A.; Kaiser, J.

2015-06-01

Characterising the dynamics of landscape scale wildfires at very high temporal resolutions is best achieved using observations from Earth Observation (EO) sensors mounted onboard geostationary satellites. As a result, a number of operational active fire products have been developed from the data of such sensors. An example of which are the Fire Radiative Power (FRP) products, the FRP-PIXEL and FRP-GRID products, generated by the Land Surface Analysis Satellite Applications Facility (LSA SAF) from imagery collected by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on-board the Meteosat Second Generation (MSG) series of geostationary EO satellites. The processing chain developed to deliver these FRP products detects SEVIRI pixels containing actively burning fires and characterises their FRP output across four geographic regions covering Europe, part of South America and northern and southern Africa. The FRP-PIXEL product contains the highest spatial and temporal resolution FRP dataset, whilst the FRP-GRID product contains a spatio-temporal summary that includes bias adjustments for cloud cover and the non-detection of low FRP fire pixels. Here we evaluate these two products against active fire data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS), and compare the results to those for three alternative active fire products derived from SEVIRI imagery. The FRP-PIXEL product is shown to detect a substantially greater number of active fire pixels than do alternative SEVIRI-based products, and comparison to MODIS on a per-fire basis indicates a strong agreement and low bias in terms of FRP values. However, low FRP fire pixels remain undetected by SEVIRI, with errors of active fire pixel detection commission and omission compared to MODIS ranging between 9-13 and 65-77% respectively in Africa. Higher errors of omission result in greater underestimation of regional FRP totals relative to those derived from simultaneously collected MODIS

The Airbag as a Supplement to Standard Restraint Systems in the AH-1 and AH-64 Attack Helicopters and Its Role in Reducing Head Strikes of the Copilot/ Gunner. Volume 1

DTIC Science & Technology

1991-01-01

shelf and locally available automotive airbag system was selected for the tests. The system was a driver’s side airbag designed by Honda Motor Company...allowance for hardware redesign or modifi- cation. Despite these limitations, the study succeeded in demonstrating a problem exists and a supplemental airbag ...JSAARL Repqrt No. 91-8 AD-A233 349 Volume’ I(3 The Airbag as a Supplement to Standard Restraint Systems in the AH-1 and AH-64 Attack Helicopters and

Fabrication and experimentation of FRP helical spring

NASA Astrophysics Data System (ADS)

Ekanthappa, J.; Shiva Shankar, G. S.; Amith, B. M.; Gagan, M.

2016-09-01

In present scenario, the automobile industry sector is showing increased interest in reducing the unsprung weight of the automobile & hence increasing the fuel Efficiency. One of the feasible sub systems of a vehicle where weight reduction may be attempted is vehicle- suspension system. Usage of composite material is a proven way to lower the component weight without any compromise in strength. The composite materials are having high specific strength, more elastic strain energy storage capacity in comparison with those of steel. Therefore, helical coil spring made of steel is replaceable by composite cylindrical helical coil spring. This research aims at preparing a re-usable mandrel (mould) of Mild steel, developing a setup for fabrication, fabrication of FRP helical spring using continuous glass fibers and Epoxy Resin (Polymer). Experimentation has been conducted on fabricated FRP helical spring to determine its strength parameters & for failure analysis. It is found that spring stiffness (K) of Glass/Epoxy helical-spring is greater than steel-coil spring with reduced weight.

Increased expression of the WNT antagonist sFRP-1 in glaucoma elevates intraocular pressure

PubMed Central

Wang, Wan-Heng; McNatt, Loretta G.; Pang, Iok-Hou; Millar, J. Cameron; Hellberg, Peggy E.; Hellberg, Mark H.; Steely, H. Thomas; Rubin, Jeffrey S.; Fingert, John H.; Sheffield, Val C.; Stone, Edwin M.; Clark, Abbot F.

2008-01-01

Elevated intraocular pressure (IOP) is the principal risk factor for glaucoma and results from excessive impedance of the fluid outflow from the eye. This abnormality likely originates from outflow pathway tissues such as the trabecular meshwork (TM), but the associated molecular etiology is poorly understood. We discovered what we believe to be a novel role for secreted frizzled-related protein-1 (sFRP-1), an antagonist of Wnt signaling, in regulating IOP. sFRP1 was overexpressed in human glaucomatous TM cells. Genes involved in the Wnt signaling pathway were expressed in cultured TM cells and human TM tissues. Addition of recombinant sFRP-1 to ex vivo perfusion-cultured human eyes decreased outflow facility, concomitant with reduced levels of β-catenin, the Wnt signaling mediator, in the TM. Intravitreal injection of an adenoviral vector encoding sFRP1 in mice produced a titer-dependent increase in IOP. Five days after vector injection, IOP increased 2 fold, which was significantly reduced by topical ocular administration of an inhibitor of a downstream suppressor of Wnt signaling. Thus, these data indicate that increased expression of sFRP1 in the TM appears to be responsible for elevated IOP in glaucoma and restoring Wnt signaling in the TM may be a novel disease intervention strategy for treating glaucoma. PMID:18274669

Efficacy of seat-mounted thoracic side airbags in the German vehicle fleet.

PubMed

Gaylor, Luke; Junge, Mirko; Abanteriba, Sylvester

2017-11-17

Thoracic side airbags (tSABs) deploy within close proximity to the occupant. Their primary purpose is to provide a protective cushion between the occupant and the intruding door. To date, various field studies investigating their injury mitigation has been limited and contradicting. The research develops efficacy estimations associated for seat-mounted tSABs in their ability to mitigate injury risk from the German collision environment. A matched cohort study using German In-Depth Accident Study (GIDAS) data was implemented and aims to investigate the efficacy of seat-mounted tSAB units in preventing thoracic injury. Inclusion in the study required a nearside occupant involved in a lateral collision where the target vehicle exhibited a design year succeeding 1990. Collisions whereby a tSAB deployed were matched on a 1:n basis to collisions of similar severity where no airbag was available in the target vehicle. The outcome of interest was an incurred bodily or thoracic regional injury. Through conditional logistic regression, an estimated efficacy value for the deployed tSAB was determined. A total of 255 collisions with the deployed tSAB matched with 414 collisions where no tSAB was present. For the given sample, results indicated that the deployed tSAB was not able to provide an unequivocal benefit to the occupant thoracic region, because individuals exposed to the deployed tSAB were at equal risk of injury (Thorax Maximum Abbreviated Injury Scale (Tho.MAIS)2+ odds ratio [OR] = 1.04, 95% confidence interval [CI], 0.41-2.62; Tho.MAIS3+ OR = 1.15, 95% CI, 0.41-3.18). When attempting to isolate an effect for skeletal injuries, a similar result was obtained. Yet, when the tSAB was coupled with a head curtain airbag, a protective effect became apparent, most noticeable for head/face/neck (HFN) injuries (OR = 0.59, 95% CI, 0.21-1.65). The reduction in occupant HFN injury risk associated with the coupled tSAB and curtain airbag may be attributable to its ability to

[Development of denture base resin. 2. Manufacturing of visible-light cured prepreg and physical properties of FRP].

PubMed

Kimura, H; Yu, P Y; Teraoka, F; Sugita, M

1989-09-01

To develop the visible light-cured FRP denture base, we investigated the physical properties and the warp of FRP plate by using various combinations of matrix resin and reinforcement. From the results of the bending test, hardness test and manipulation processing, the matrix resin of Bis-GMA/UDMA/3 G at 48/48/4 wt% was determined. The sateen weave's glasscloth as the reinforcement of the prepreg was used. The maximum plies included FRP of 0.5 mm, 0.8 and 1.0 mm thickness have the same maximum bending strengths of 45 kgf/mm2, which is about 5 times larger than that of conventional acrylic resin. The warp of these FRP plates were not found.

Martian Surface & Pathfinder Airbags

NASA Technical Reports Server (NTRS)

1997-01-01

This image of the Martian surface was taken in the afternoon of Mars Pathfinder's first day on Mars. Taken by the Imager for Mars Pathfinder (IMP camera), the image shows a diversity of rocks strewn in the foreground. A hill is visible in the distance (the notch within the hill is an image artifact). Airbags are seen at the lower right.

The IMP is a stereo imaging system with color capability provided by 24 selectable filters -- twelve filters per 'eye.' It stands 1.8 meters above the Martian surface, and has a resolution of two millimeters at a range of two meters.

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

Vibrational characteristics of FRP-bonded concrete interfacial defects in a low frequency regime

NASA Astrophysics Data System (ADS)

Cheng, Tin Kei; Lau, Denvid

2014-04-01

As externally bonded fiber-reinforced polymer (FRP) is a critical load-bearing component of strengthened or retrofitted civil infrastructures, the betterment of structural health monitoring (SHM) methodology for such composites is imperative. Henceforth the vibrational characteristics of near surface interfacial defects involving delamination and trapped air pockets at the FRP-concrete interface are investigated in this study using a finite element approach. Intuitively, due to its lower interfacial stiffness compared with an intact interface, a damaged region is expected to have a set of resonance frequencies different from an intact region when excited by acoustic waves. It has been observed that, when excited acoustically, both the vibrational amplitudes and frequency peaks in the response spectrum of the defects demonstrate a significant deviation from an intact FRP-bonded region. For a thin sheet of FRP bonded to concrete with sizable interfacial defects, the fundamental mode under free vibration is shown to be relatively low, in the order of kHz. Due to the low resonance frequencies of the defects, the use of low-cost equipment for interfacial defect detection via response spectrum analysis is highly feasible.

Perspectives Of Employment Of Pultruded FRP Structural Elements In Seismic Engineering Field

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

Russo, Salvatore; Silvestri, Mirko

2008-07-08

Today the employment of FRP material in structural engineering is in common use, with excellent results in term of applications especially as reinforcement of existing structures. This success is related to the very reduced weight of FRP material, to its performance in term of strength and durability and thanks to the easy use in technical application. There is a modern way to use this material disguised as structural pultruded element (with weight equal to 1600-1800 kg/m{sup 3}) in new constructions, local reinforcements and in other seismic applications. Actually the international technical and scientific literature in form of draft, recommendations andmore » researches on this topic is very rich also taking into account Italian contribution. Some interesting applications of all FRP structures in seismic engineering field are showed in this research in real terms and in form of capability.« less

Parametric Study of Shear Strength of Concrete Beams Reinforced with FRP Bars

NASA Astrophysics Data System (ADS)

Thomas, Job; Ramadass, S.

2016-09-01

Fibre Reinforced Polymer (FRP) bars are being widely used as internal reinforcement in structural elements in the last decade. The corrosion resistance of FRP bars qualifies its use in severe and marine exposure conditions in structures. A total of eight concrete beams longitudinally reinforced with FRP bars were cast and tested over shear span to depth ratio of 0.5 and 1.75. The shear strength test data of 188 beams published in various literatures were also used. The model originally proposed by Indian Standard Code of practice for the prediction of shear strength of concrete beams reinforced with steel bars IS:456 (Plain and reinforced concrete, code of practice, fourth revision. Bureau of Indian Standards, New Delhi, 2000) is considered and a modification to account for the influence of the FRP bars is proposed based on regression analysis. Out of the 196 test data, 110 test data is used for the regression analysis and 86 test data is used for the validation of the model. In addition, the shear strength of 86 test data accounted for the validation is assessed using eleven models proposed by various researchers. The proposed model accounts for compressive strength of concrete ( f ck ), modulus of elasticity of FRP rebar ( E f ), longitudinal reinforcement ratio ( ρ f ), shear span to depth ratio ( a/ d) and size effect of beams. The predicted shear strength of beams using the proposed model and 11 models proposed by other researchers is compared with the corresponding experimental results. The mean of predicted shear strength to the experimental shear strength for the 86 beams accounted for the validation of the proposed model is found to be 0.93. The result of the statistical analysis indicates that the prediction based on the proposed model corroborates with the corresponding experimental data.

An exact stiffness theory for unidirectional xFRP composites

NASA Astrophysics Data System (ADS)

Klasztorny, M.; Konderla, P.; Piekarski, R.

2009-01-01

UD xFRP composites, i.e., isotropic plastics reinforced with long transversely isotropic fibres packed unidirectionally according to the hexagonal scheme are considered. The constituent materials are geometrically and physically linear. The previous formulations of the exact stiffness theory of such composites are revised, and the theory is developed further based on selected boundary-value problems of elasticity theory. The numerical examples presented are focussed on testing the theory with account of previous variants of this theory and experimental values of the effective elastic constants. The authors have pointed out that the exact stiffness theory of UD xFRP composites, with the modifications proposed in our study, will be useful in the engineering practice and in solving the current problems of the mechanics of composite materials.

Automotive Airbag Safety Enhancement Final Report CRADA No. TSB-1165-95

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

Cutting, Jack; Durrell, Robert

The Vehicle Safety systems (VSS) Division of Quantic Industries, Inc. (QII) manufactured automotive airbag components. When both the driver and the passenger side airbags inflated in a tightly sealed passenger compartment, the compression of the surrounding air could and, in some instances, would cause damage to the eardrums of the occupants. The Aerospace and Division (ADD) of QII had partially developed the technology to fracture the canopy of a jet aircraft at the time of pilot ejection. The technical problem was how to adapt the canopy fracturing technology to the rear window of a motor vehicle in a safe andmore » cost effective manner. The existing approach was to replace the embedded rear window defroster with a series-parallel network of exploding bridge wires (EBWs). This would still provide the defrost function at low voltage/ current, but would cause fracturing of the window when a high current/voltage pulse was applied without pyrotechnics or explosives. The elements of this system were the embedded EBW network and a trunk-mounted fireset. The fireset would store the required energy to fire the network upon the receipt of a trigger signal from the existing air bag crash sensor.« less

Estimation of seatbelt and frontal-airbag effectiveness in trucks : U.S. and Chinese perspectives.

DOT National Transportation Integrated Search

2013-01-01

The objectives of this study were (1) to estimate the effectiveness of seatbelts and driver : airbags for mitigating medium- and heavy-truck driver injuries, and (2) to discuss the : implication of these estimates with respect to truck-driving condit...

Development of advanced grid stiffened (AGS) fiber reinforced polymer (FRP) tube-encased concrete columns : [technical summary].

DOT National Transportation Integrated Search

2013-03-01

In recent years, the use of fi ber reinforced polymer (FRP) tube-encased concrete columns for new construction and rebuilding : of engineering structures has increased. The purpose in FRP tube-encased concrete columns is to replace the steel rebar by...

Large scale distribution monitoring of FRP-OF based on BOTDR technique for infrastructures

NASA Astrophysics Data System (ADS)

Zhou, Zhi; He, Jianping; Yan, Kai; Ou, Jinping

2007-04-01

BOTDA(R) sensing technique is considered as one of the most practical solution for large-sized structures as the instrument. However, there is still a big obstacle to apply BOTDA(R) in large-scale area due to the high cost and the reliability problem of sensing head which is associated to the sensor installation and survival. In this paper, we report a novel low-cost and high reliable BOTDA(R) sensing head using FRP(Fiber Reinforced Polymer)-bare optical fiber rebar, named BOTDA(R)-FRP-OF. We investigated the surface bonding and its mechanical strength by SEM and intensity experiments. Considering the strain difference between OF and host matrix which may result in measurement error, the strain transfer from host to OF have been theoretically studied. Furthermore, GFRP-OFs sensing properties of strain and temperature at different gauge length were tested under different spatial and readout resolution using commercial BOTDA. Dual FRP-OFs temperature compensation method has also been proposed and analyzed. And finally, BOTDA(R)-OFs have been applied in Tiyu west road civil structure at Guangzhou and Daqing Highway. This novel FRP-OF rebar shows both high strengthen and good sensing properties, which can be used in long-term SHM for civil infrastructures.

Smart FRP Composite Sandwich Bridge Decks in Cold Regions

DOT National Transportation Integrated Search

2011-07-01

In this study, new and integrated Smart honeycomb Fiber-Reinforced Polymer (S-FRP) : sandwich materials for various transportation construction applications, with particular emphasis : on highway bridge decks in cold regions, were developed and teste...

Smart FRP Composite Sandwich Bridge Decks in Cold Regions

DOT National Transportation Integrated Search

2011-07-01

In this study, new and integrated Smart honeycomb Fiber-Reinforced Polymer (S-FRP) sandwich materials for various transportation construction applications, with particular emphasis on highway bridge decks in cold regions, were developed and tested. T...

Benefits of Australian Design Rule 69 (full frontal crash protection) and airbags in frontal crashes in Australia

PubMed Central

Fitzharris, Michael; Fildes, Brian; Newstead, Stuart; Logan, David

2004-01-01

In-depth data at MUARC was used to evaluate the Australian Design Rule 69 (ADR69) - Full frontal dynamic crash requirement, as well as the effectiveness of frontal airbag deployment on injury risk and associated cost of injury. ADR69 was introduced in Australia in mid-1995 and was based largely on the US equivalent FMVSS-208. The results indicate reductions in excess of 90% in the likelihood of sustaining AIS 2+ injuries in body regions where frontal airbags would be expected to benefit. The average injury cost savings for drivers of post-ADR69 manufactured vehicles was found to be up to AUD$19,000 depending on body region considered. Limitations and implications of these findings are discussed.

Fiber reinforced polymer (FRP) composite piles used on pier rehabilitation, Little Diamond Island, Casco Bay, Portland, Maine.

DOT National Transportation Integrated Search

2012-10-01

Fiber reinforced polymer (FRP) composite piles were used on a pier rehabilitation project at : Little Diamond Island in Casco Bay near Portland Maine. The project was the replacement : of an aging wooden pier at the ferry berthing terminal. The FRP p...

Study on effects of different patterns and cracking for wastes FRP (used banner) wrapping on compressive strength of confined concrete

NASA Astrophysics Data System (ADS)

Syazani Leman, Alif; Shahidan, Shahiron; Azmi, M. A. M.; Syamir Senin, Mohamad; Ali, N.; Abdullah, S. R.; Zuki, S. S. Mohd; Ibrahim, M. H. Wan; Nazri, Fadzli Mohamed

2017-11-01

Previous researches have shown that FRP are being introduce into wide variety of civil engineering applications. Fibre Reinforce Concrete (FRP) are also used as repairing method in concrete structures. FRP such as S-glass, AR-glass, E-glass, C-glass, and Aramid Fibre are the common material used in industry. The FRP strips provide the necessary longitudinal and hoop reinforcement. However, there are lots waste materials that can be form as fibre and used in repairing. Banner is a type of waste material fibre that can be used in repairing. In this study, banner will be used as the replacement of the common FRP. The confined concrete (cylinder) of 300mm height and 150mm diameter were cast with M35 grade concrete and tested until it is crack. Next banner are used as the wrapping along the cracking of the concrete with three different pattern that are full wrapping, two band wrapping and cross wrapping using epoxy. Epoxy is a common name for a type of strong adhesive used for sticking things together and covering surface. The objective of this study is to determine the maximum strength and the effect of different patterns wrapping of FRP (banner) on the compressive strength of confined concrete. The results are shows that banner are suitable as a replacement of material for FRP.

Benefits of Australian Design Rule 69 (full frontal crash protection) and airbags in frontal crashes in Australia.

PubMed

Fitzharris, Michael; Fildes, Brian; Newstead, Stuart; Logan, David

2004-01-01

In-depth data at MUARC was used to evaluate the Australian Design Rule 69 (ADR69) - Full frontal dynamic crash requirement, as well as the effectiveness of frontal airbag deployment on injury risk and associated cost of injury. ADR69 was introduced in Australia in mid-1995 and was based largely on the US equivalent FMVSS-208. The results indicate reductions in excess of 90% in the likelihood of sustaining AIS 2+ injuries in body regions where frontal airbags would be expected to benefit. The average injury cost savings for drivers of post-ADR69 manufactured vehicles was found to be up to AUD19,000 dollars depending on body region considered. Limitations and implications of these findings are discussed.

Detection of Fatigue Crack in Basalt FRP Laminate Composite Pipe using Electrical Potential Change Method

NASA Astrophysics Data System (ADS)

Altabey, Wael A.; Noori, Mohammed

2017-05-01

Novel modulation electrical potential change (EPC) method for fatigue crack detection in a basalt fibre reinforced polymer (FRP) laminate composite pipe is carried out in this paper. The technique is applied to a laminate pipe with an embedded crack in three layers [0º/90º/0º]s. EPC is applied for evaluating the dielectric properties of basalt FRP pipe by using an electrical capacitance sensor (ECS) to discern damages in the pipe. Twelve electrodes are mounted on the outer surface of the pipe and the changes in the modulation dielectric properties of the piping system are analyzed to detect damages in the pipe. An embedded crack is created by a fatigue internal pressure test. The capacitance values, capacitance change and node potential distribution of ECS electrodes are calculated before and after crack initiates using a finite element method (FEM) by ANSYS and MATLAB, which are combined to simulate sensor characteristics and fatigue behaviour. The crack lengths of the basalt FRP are investigated for various number of cycles to failure for determining crack growth rate. Response surfaces are adopted as a tool for solving inverse problems to estimate crack lengths from the measured electric potential differences of all segments between electrodes to validate the FEM results. The results show that, the good convergence between the FEM and estimated results. Also the results of this study show that the electrical potential difference of the basalt FRP laminate increases during cyclic loading, caused by matrix cracking. The results indicate that the proposed method successfully provides fatigue crack detection for basalt FRP laminate composite pipes.

Cutaway of SEIS (Artist's Concept)

NASA Image and Video Library

2018-04-09

This artist's rendering shows a cutaway of the Seismic Experiment for Interior Structure instrument, or SEIS, which will fly as part of NASA's Mars InSight lander. SEIS is a highly sensitive seismometer that will be used to detect marsquakes from the Red Planet's surface for the first time. There are two layers in this cutaway. The outer layer is the Wind and Thermal Shield -- a covering that protects the seismometer from the Martian environment. The wind on Mars, as well as extreme temperature changes, could affect the highly sensitive instrument. The inside layer is SEIS itself, a brass-colored dome that houses the instrument's three pendulums. These insides are inside a titanium vacuum chamber to further isolate them from temperature changes on the Martian surface. https://photojournal.jpl.nasa.gov/catalog/PIA22320

Martian Terrain, Unfurled Rover Ramps & Deflated Airbags

NASA Image and Video Library

1997-07-05

The Imager for Mars Pathfinder (IMP) took this image of surrounding terrain in the mid-morning on Mars (2:30 PM Pacific Daylight Time) earlier today. Part of the small rover, Sojourner, is visible on the left side of the picture. The tan cylinder to the right of the rover is one of two rolled-up ramps by which the rover will descend to the ground. The white, billowy material in the center of the picture is part of the airbag system. Many rocks of different shapes and sizes are visible between the lander and the horizon. Two hills are visible on the horizon. The notch on the left side of the leftmost conical hill is an artifact of the processing of this picture. http://photojournal.jpl.nasa.gov/catalog/PIA00613

Response of No-Name Creek FRP Bridge to Local Weather

DOT National Transportation Integrated Search

2012-09-01

Since 1996, over 30 Fiber Reinforced Polymer (FRP) composite bridges have been installed in the United States. Bridge : locations are in Kansas, Missouri, New York, Iowa, Colorado, West Virginia, Ohio, California, Idaho, Washington, Pennsylvania, : I...

Styrene vapor control systems in FRP yacht plants.

PubMed

Todd, W F

1985-01-01

The production of large (greater than 25-ft) fiber-reinforced plastic (FRP) yachts has presented problems of styrene exposure in excess of the Occupational Safety and Health Administration permissible exposure level (OSHA PEL) of 100 ppm. Also, the National Institute for Occupational Safety and Health (NIOSH) is currently recommending a 10-hour workshift, 40-hour workweek time weighted average (TWA) of 50 ppm for styrene. Meeting this challenge will require a system of engineering, work practice, personal protective equipment, and monitoring control measures. NIOSH has performed a study of the engineering controls in three FRP yacht plants. Work practices and the use of personal protective equipment (PPE) were also considered in the evaluation. The three systems evaluated included a dilution system, a local ventilation system, and a push-pull ventilation system. The cost of constructing and operating these systems was not evaluated in this study. Study results indicated that each type of ventilation system can meet the present PEL of 100 ppm styrene; however, it is not certain that these systems can meet a lower PEL of 50 ppm styrene.

Research notes : non-destructive evaluation of FRP-strengthened reinforced concrete.

DOT National Transportation Integrated Search

2005-04-01

Many reinforced concrete structures across the country are being strengthened with fiber reinforced polymer (FRP) composites to increase the load capacity. In many cases, composites provide the most cost effective strengthening option, and they do no...

H-60A/L Passenger Airbag Protection: Vertical and Horizontal Impact Tests

DTIC Science & Technology

2013-04-30

aft facing seating . While impact testing has been widely performed on ejection seats , only limited testing has been done on helicopter seating ...manikins with the LARD scaled to represent large occupants in the aerospace environment. LARD is also used by the Air Force and JSF in ejection seat ...for all rigid seat tests, resulting in no notable differences (manikin motion , manikin response) between the standard and airbag restraints. The

Long term monitoring of mechanical properties of FRP repair materials.

DOT National Transportation Integrated Search

2013-06-01

Over the years, Fiber Reinforced Polymer (FRP) composites have gained popularity in transportation infrastructure as a material able to restore and increase the capacity of existing concrete elements. Properties such as a high strength to weight rati...

Biomechanics of side impact: injury criteria, aging occupants, and airbag technology.

PubMed

Yoganandan, Narayan; Pintar, Frank A; Stemper, Brian D; Gennarelli, Thomas A; Weigelt, John A

2007-01-01

This paper presents a survey of side impact trauma-related biomedical investigations with specific reference to certain aspects of epidemiology relating to the growing elderly population, improvements in technology such as side airbags geared toward occupant safety, and development of injury criteria. The first part is devoted to the involvement of the elderly by identifying variables contributing to injury including impact severity, human factors, and national and international field data. This is followed by a survey of various experimental models used in the development of injury criteria and tolerance limits. The effects of fragility of the elderly coupled with physiological changes (e.g., visual, musculoskeletal) that may lead to an abnormal seating position (termed out-of-position) especially for the driving population are discussed. Fundamental biomechanical parameters such as thoracic, abdominal and pelvic forces; upper and lower spinal and sacrum accelerations; and upper, middle and lower chest deflections under various initial impacting conditions are evaluated. Secondary variables such as the thoracic trauma index and pelvic acceleration (currently adopted in the United States Federal Motor Vehicle Safety Standards), peak chest deflection, and viscous criteria are also included in the survey. The importance of performing research studies with specific focus on out-of-position scenarios of the elderly and using the most commonly available torso side airbag as the initial contacting condition in lateral impacts for occupant injury assessment is emphasized.

Biomechanics of side impact: Injury criteria, aging occupants, and airbag technology

PubMed Central

Yoganandan, Narayan; Pintar, Frank A.; Stemper, Brian D.; Gennarelli, Thomas A.; Weigelt, John A.

2007-01-01

This paper presents a survey of side impact trauma-related biomedical investigations with specific reference to certain aspects of epidemiology relating to the growing elderly population, improvements in technology such as side airbags geared toward occupant safety, and development of injury criteria. The first part is devoted to the involvement of the elderly by identifying variables contributing to injury including impact severity, human factors, and national and international field data. This is followed by a survey of various experimental models used in the development of injury criteria and tolerance limits. The effects of fragility of the elderly coupled with physiological changes (e.g., visual, musculoskeletal) that may lead to an abnormal seating position (termed out-of-position) especially for the driving population are discussed. Fundamental biomechanical parameters such as thoracic, abdominal and pelvic forces; upper and lower spinal and sacrum accelerations; and upper, middle and lower chest deflections under various initial impacting conditions are evaluated. Secondary variables such as the thoracic trauma index and pelvic acceleration (currently adopted in the United States Federal Motor Vehicle Safety Standards), peak chest deflection, and viscous criteria are also included in the survey. The importance of performing research studies with specific focus on out-of-position scenarios of the elderly and using the most commonly available torso side airbag as the initial contacting condition in lateral impacts for occupant injury assessment is emphasized. PMID:16527285

Finite element modeling of concrete structures strengthened with FRP laminates

DOT National Transportation Integrated Search

2001-05-01

Linear and non-linear method models were developed for a reinforced concrete bridge that had been strengthened with fiber reinforced polymer (FRP) composites. ANSYS and SAP2000 modeling software were used; however, most of the development effort used...

Long-term monitoring of mechanical properties of FRP repair materials.

DOT National Transportation Integrated Search

2013-07-01

Fiber- reinforced polymer composites (FRP) are an attractive repair option for existing concrete structures. : CDOT has used this material on some projects, in particular the repair of the Castlewood Canyon Bridge in : 2003. Further use of the materi...

An experimentally based analytical model for the shear capacity of FRP-strengthened reinforced concrete beams

NASA Astrophysics Data System (ADS)

Pellegrino, C.; Modena, C.

2008-05-01

This paper deals with the shear strengthening of Reinforced Concrete (RC) flexural members with externally bonded Fiber-Reinforced Polymers (FRPs). The interaction between an external FRP and an internal transverse steel reinforcement is not considered in actual code recommendations, but it strongly influences the efficiency of the shear strengthening rehabilitation technique and, as a consequence, the computation of interacting contributions to the nominal shear strength of beams. This circumstance is also discussed on the basis of the results of an experimental investigation of rectangular RC beams strengthened in shear with "U-jacketed" carbon FRP sheets. Based on experimental results of the present and other investigations, a new analytical model for describing the shear capacity of RC beams strengthened according to the most common schemes (side-bonded and "U-jacketed"), taking into account the interaction between steel and FRP shear strength contributions, is proposed.

Behavior of Insulated Carbon-FRP-Strengthened RC Beams Exposed to Fire

NASA Astrophysics Data System (ADS)

Sayin, B.

2014-09-01

There are two main approaches to improving the fire resistance of fiber-reinforced polymer (FRP) systems. While the most common method is to protect or insulate the FRP system, an other way is to use fibers and resins with a better fire performance. This paper presents a numerical investigation into the five protection behavior of insulated carbon-fiber-reinforced-polymer (CFRP)-strengthened reinforced concrete (RC) beams. The effects of external loading and thermal expansion of materials at elevated temperatures are taken into consideration in a finite-element model. The validity of the numerical model is demonstrated with results from an existing experimental study on insulated CFRP-strengthened RC beams. Conclusions of this investigation are employed to predict the structural behavior of CFRP-strengthened concrete structures.

The Effects of Curtain Airbag on Occupant Kinematics and Injury Index in Rollover Crash

PubMed Central

Li, Hongyun; Cui, Dong; Lu, Shuang

2018-01-01

Background Occupant injuries in rollover crashes are associated with vehicle structural performance, as well as the restraint system design. For a better understanding of the occupant kinematics and injury index in certain rollover crash, it is essential to carry out dynamic vehicle rollover simulation with dummy included. Objective This study focused on effects of curtain airbag (CAB) parameters on occupant kinematics and injury indexes in a rollover crash. Besides, optimized parameters of the CAB were proposed for the purpose of decreasing the occupant injuries in such rollover scenario. Method and Material The vehicle motion from the physical test was introduced as the input for the numerical simulation, and the 50% Hybrid III dummy model from the MADYMO database was imported into a simulation model. The restraint system, including a validated CAB module, was introduced for occupant kinematics simulation and injury evaluation. TTF setting, maximum inflator pressure, and protection area of the CAB were analysed. Results After introducing the curtain airbag, the maximum head acceleration was reduced from 91.60 g to 49.52 g, and the neck Mx and neck Fz were reduced significantly. Among these CAB parameters, the TTF setting had the largest effect on the head acceleration which could reduce 8.6 g furthermore after optimization. The neck Fz was decreased from 3766.48 N to 2571.77 N after optimization of CAB protection area. Conclusions Avoiding hard contact is critical for the occupant protection in the rollover crashes. The simulation results indicated that occupant kinematics and certain injury indexes were improved with the help of CAB in such rollover scenario. Appropriate TTF setting and inflator selection could benefit occupant kinematics and injury indexes. Besides, it was advised to optimize the curtain airbag thickness around the head contact area to improve head and neck injury indexes. PMID:29765463

Aspects of the passenger airbag E.C.U. location

NASA Astrophysics Data System (ADS)

Soica, A.

2016-08-01

Road accidents represent the dark side of road traffic, their consequences leading to material damage and often to vehicle occupant fatalities. Passive safety systems offer a high level of protection to vehicle occupants; yet, depending on a number of constructive factors and not only, these systems can not always ensure a high survival rate. The costs of road traffic accidents are to be borne by the whole society, with high amounts of money required. In this paper we analyze how the collision is felt in various points on the vehicle, at a given time and how this may affect the proper functioning of the passive safety systems, especially the airbag system.

Experimental evaluation and design of unfilled and concrete-filled FRP composite piles : Task 5 : laminate durability testing : final report.

DOT National Transportation Integrated Search

2015-05-01

The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP composite piles for load-bearing in bridges. This report covers Task 5, Laminate Durability Testing. : Mechanical properties of the FRP mat...

Design of FRP systems for strengthening concrete girders in shear.

DOT National Transportation Integrated Search

2011-06-01

FRP systems have been used on a project-specific basis for the last two decades. They are now becoming a widely accepted method of : strengthening concrete structures. The acceptance and utilization of these new strengthening techniques depend on the...

Effect of the tapered end of a FRP plate on the interfacial stresses in a strengthened beam used in civil engineering applications

NASA Astrophysics Data System (ADS)

Mahi, B. E.; Benrahou, K. H.; Belakhdar, Kh.; Tounsi, A.; Bedia, E. A. Adda

2014-09-01

The interfacial stresses of a beam strengthened with a FRP plate, which is widely employed in the civil engineering for rehabilitation and retrofitting of conventional structures, is investigated. An important feature of the reinforced beam is significant stress concentrations in the adhesive at the ends of the FRP plate. To reduce these interfacial stresses, a FRP plate with a tapered end is often used. The finite-difference method is utilized in this work to predict the distribution of interfacial stresses in beams strengthened with a FRP plate having a tapered end. Numerical results from the analysis are presented to demonstrate the advantages of using tapers in the design of strengthened beams.

Parental awareness and perception for correct use of child restraint systems and airbags in Brazil.

PubMed

Souza, Bruno Gonçalves Schröder E; Evangelista de Melo, Tiago; Pereira Lisboa, Tales; Bastos Miranda, Marcos; Schroder E Souza, Thiago Gonçalves; de Oliveira, Valdeci Manoel

2017-02-17

The objective of this study was to obtain information about the current knowledge and habits of parents who transport children in cars in Brazil. A cross-sectional survey was conducted using specifically designed self-report questionnaires to parents of children attending a private pediatric office in a town in southwest Brazil. Data were collected regarding children's age, gender, height, and weight and possession of an automobile child restraint system (CRS), its type, frequency and adequacy of use, and reasons for not possessing or not using the devices. Parents were asked whether their cars were equipped with airbags and about the use of the restraints in seats with airbags. We interviewed parents of 293 children transported in cars who met the criteria for use of a CRS. Children were younger than 1 year in 15.3% of the cases, between 1 and 4 years in 38.6%, and older than 4 in 46.1%. Cars were equipped with CRS in 78.5% of the cases, but in only 58% of the cases was the device proper for child's age and adequately installed in the seat. Among owners of the devices, 84.3% reported that they always used it. Reasons for infrequency were forgetting the device at home or in another car (6.4%), the child disliking the device (3.2%), or the false impression that the child was grown enough not to use it (3.2%)l 87.1% did not justify why they did not always use the CRS. Considering type of CRS, correct installation of the seat, and frequency of use, only 44.4% of children under 1 year, 69.9% of those 1 to 4 years, and 52.6% over age 4 were protected. Only 28.6% of the parents knew that children should never be positioned in a seat with active airbags. Considering appropriateness for age, correctness of installation (in the back seat in the correct orientation), and frequency of use, only 50.85% (149/293) of the children were reported as always protected with a CRS. Children between 1 and 4 years were more likely to always use a CRS in this Brazilian survey. We were

Vacuum Surface Flashover Characteristics and Secondary Electron Emission Characteristics of Epoxy Resin and FRP Insulator

NASA Astrophysics Data System (ADS)

Yamano, Yasushi; Takahashi, Masahiro; Kobayashi, Shinichi; Hanada, Masaya; Ikeda, Yoshitaka

Neutral beam injectors (NBI) used for JT-60 are required to generate negative ions of 500 keV energies. To produce such high-energy ions, the electrostatic accelerators consisting of 3-stage of electrodes and three insulator rings are applied. The insulators are made of Fiberglass Reinforced Plastic (FRP) which is composed of epoxy resin and glass fibers. The surface discharges along the insulators are one of the most serious problems in the development of NBI. To increase the hold-off voltage against surface flashover events, it is necessary to investigate the FRP and epoxy resin insulator properties related to surface discharges in vacuum. This paper describes surface flashover characteristics for epoxy resin, FRP and Alumina samples under vacuum condition. In addition, the measurements of secondary electron emission (SEE) characteristics are also reported. These are important parameters to analyze surface discharge characteristics of insulators in vacuum.

Rover, Airbags & Martian Terrain

NASA Image and Video Library

1997-07-04

This picture from Mars Pathfinder was taken at 9:30 AM in the martian morning (2:30 PM Pacific Daylight Time), after the spacecraft landed earlier today (July 4, 1997). The Sojourner rover is perched on one of three solar panels. The rover is 65 cm (26 inches) long by 18 cm (7 inches) tall; each of its wheels is about 13 cm (5 inches) high. The white material to the left of the front of the rover is part of the airbag system used to cushion the landing. Many rocks of different of different sizes can be seen, set in a background of reddish soil. The landing site is in the mouth of an ancient channel carved by water. The rocks may be primarily flood debris. The horizon is seen towards the top of the picture. The light brown hue of the sky results from suspended dust. Pathfinder, a low-cost Discovery mission, is the first of a new fleet of spacecraft that are planned to explore Mars over the next ten years. Mars Global Surveyor, already en route, arrives at Mars on September 11 to begin a two year orbital reconnaissance of the planet's composition, topography, and climate. Additional orbiters and landers will follow every 26 months. http://photojournal.jpl.nasa.gov/catalog/PIA00608

Estimating Landscape Fire Particulate Matter (PM) Emissions over Southern Africa using MSG-SEVIRI Fire Radiative Power (FRP) and MODIS Aerosol Optical Thickness Observations

NASA Astrophysics Data System (ADS)

Mota, Bernardo; Wooster, Martin J.

2016-04-01

The approach to estimating landscape fire fuel consumption based on the remotely sensed fire radiative power (FRP) thermal energy release rate, as opposed to burned area, is now relatively widely used in studies of fire emissions, including operationally within the Copernicus Atmosphere Monitoring Service (CAMS). Nevertheless, there are still limitations to the approach, including uncertainties associated with using only the few daily overpasses typically provided by polar orbiting satellite systems, the conversion between FRP and smoke emissions, and the increased likelihood that the more frequent data from geostationary systems fails to detect the (probably highly numerous) smaller (i.e. low FRP) component of a regions fire regime. In this study, we address these limitations to directly estimate fire emissions of Particular Matter (PM; or smoke aerosols) by presenting an approach combining the "bottom-up" FRP observations available every 15 minutes across Africa from the Meteosat Spinning Enhanced Visible and Infrared Imager (SEVIRI) Fire Radiative Product (FRP) processed at the EUMETSAT LSA SAF, and the "top-down" aerosol optical thickness (AOT) measures of the fire plumes themselves as measured by the Moderate-resolution Imaging Spectro-radiometer (MODIS) sensors aboard the Terra (MOD04_L2) and Aqua (MYD04_L2) satellites. We determine PM emission coefficients that relate directly to FRP measures by combining these two datasets, and the use of the almost continuous geostationary FRP observations allows us to do this without recourse to (uncertain) data on wind speed at the (unknown) height of the matching plume. We also develop compensation factors to address the detection limitations of small/low intensity (low FRP) fires, and remove the need to estimate fuel consumption by going directly from FRP to PM emissions. We derive the smoke PM emissions coefficients per land cover class by comparing the total fire radiative energy (FRE) released from individual fires

FRCM and FRP composites for the repair of damaged PC girders.

DOT National Transportation Integrated Search

2015-01-01

Fabric-reinforced-cementitious-matrix (FRCM) and fiber-reinforced polymer (FRP) composites have : emerged as novel strengthening technologies. FRCM is a composite material consisting of a sequence of : one or more layers of cement-based matrix reinfo...

Development of a self-stressing NiTiNb shape memory alloy (SMA)/fiber reinforced polymer (FRP) patch

NASA Astrophysics Data System (ADS)

El-Tahan, M.; Dawood, M.; Song, G.

2015-06-01

The objective of this research is to develop a self-stressing patch using a combination of shape memory alloys (SMAs) and fiber reinforced polymer (FRP) composites. Prestressed carbon FRP patches are emerging as a promising alternative to traditional methods to repair cracked steel structures and civil infrastructure. However, prestressing these patches typically requires heavy and complex fixtures, which is impractical in many applications. This paper presents a new approach in which the prestressing force is applied by restraining the shape memory effect of NiTiNb SMA wires. The wires are subsequently embedded in an FRP overlay patch. This method overcomes the practical challenges associated with conventional prestressing. This paper presents the conceptual development of the self-stressing patch with the support of experimental observations. The bond between the SMA wires and the FRP is evaluated using pull-out tests. The paper concludes with an experimental study that evaluates the patch response during activation subsequent monotonic tensile loading. The results demonstrate that the self-stressing patch with NiTiNb SMA is capable of generating a significant prestressing force with minimal tool and labor requirements.

Damping mathematical modelling and dynamic responses for FRP laminated composite plates with polymer matrix

NASA Astrophysics Data System (ADS)

Liu, Qimao

2018-02-01

This paper proposes an assumption that the fibre is elastic material and polymer matrix is viscoelastic material so that the energy dissipation depends only on the polymer matrix in dynamic response process. The damping force vectors in frequency and time domains, of FRP (Fibre-Reinforced Polymer matrix) laminated composite plates, are derived based on this assumption. The governing equations of FRP laminated composite plates are formulated in both frequency and time domains. The direct inversion method and direct time integration method for nonviscously damped systems are employed to solve the governing equations and achieve the dynamic responses in frequency and time domains, respectively. The computational procedure is given in detail. Finally, dynamic responses (frequency responses with nonzero and zero initial conditions, free vibration, forced vibrations with nonzero and zero initial conditions) of a FRP laminated composite plate are computed using the proposed methodology. The proposed methodology in this paper is easy to be inserted into the commercial finite element analysis software. The proposed assumption, based on the theory of material mechanics, needs to be further proved by experiment technique in the future.

Polyurethane foam infill for fiber-reinforced polymer (FRP) bridge deck panels.

DOT National Transportation Integrated Search

2014-05-01

The objective of the proposed research is to develop, test, and evaluate fiber-reinforced, polyurethane foams to replace the costly : honeycomb construction currently used to manufacture FRP bridge deck panels. The effort will focus on developing an ...

Use of a Molecular Decoy to Segregate Transport from Antigenicity in the FrpB Iron Transporter from Neisseria meningitidis

PubMed Central

Saleem, Muhammad; Prince, Stephen M.; Rigby, Stephen E. J.; Imran, Muhammad; Patel, Hema; Chan, Hannah; Sanders, Holly; Maiden, Martin C. J.; Feavers, Ian M.; Derrick, Jeremy P.

2013-01-01

FrpB is an outer membrane transporter from Neisseria meningitidis, the causative agent of meningococcal meningitis. It is a member of the TonB-dependent transporter (TBDT) family and is responsible for iron uptake into the periplasm. FrpB is subject to a high degree of antigenic variation, principally through a region of hypervariable sequence exposed at the cell surface. From the crystal structures of two FrpB antigenic variants, we identify a bound ferric ion within the structure which induces structural changes on binding which are consistent with it being the transported substrate. Binding experiments, followed by elemental analysis, verified that FrpB binds Fe3+ with high affinity. EPR spectra of the bound Fe3+ ion confirmed that its chemical environment was consistent with that observed in the crystal structure. Fe3+ binding was reduced or abolished on mutation of the Fe3+-chelating residues. FrpB orthologs were identified in other Gram-negative bacteria which showed absolute conservation of the coordinating residues, suggesting the existence of a specific TBDT sub-family dedicated to the transport of Fe3+. The region of antigenic hypervariability lies in a separate, external sub-domain, whose structure is conserved in both the F3-3 and F5-1 variants, despite their sequence divergence. We conclude that the antigenic sub-domain has arisen separately as a result of immune selection pressure to distract the immune response from the primary transport function. This would enable FrpB to function as a transporter independently of antibody binding, by using the antigenic sub-domain as a ‘molecular decoy’ to distract immune surveillance. PMID:23457610

Use of a molecular decoy to segregate transport from antigenicity in the FrpB iron transporter from Neisseria meningitidis.

PubMed

Saleem, Muhammad; Prince, Stephen M; Rigby, Stephen E J; Imran, Muhammad; Patel, Hema; Chan, Hannah; Sanders, Holly; Maiden, Martin C J; Feavers, Ian M; Derrick, Jeremy P

2013-01-01

FrpB is an outer membrane transporter from Neisseria meningitidis, the causative agent of meningococcal meningitis. It is a member of the TonB-dependent transporter (TBDT) family and is responsible for iron uptake into the periplasm. FrpB is subject to a high degree of antigenic variation, principally through a region of hypervariable sequence exposed at the cell surface. From the crystal structures of two FrpB antigenic variants, we identify a bound ferric ion within the structure which induces structural changes on binding which are consistent with it being the transported substrate. Binding experiments, followed by elemental analysis, verified that FrpB binds Fe(3+) with high affinity. EPR spectra of the bound Fe(3+) ion confirmed that its chemical environment was consistent with that observed in the crystal structure. Fe(3+) binding was reduced or abolished on mutation of the Fe(3+)-chelating residues. FrpB orthologs were identified in other Gram-negative bacteria which showed absolute conservation of the coordinating residues, suggesting the existence of a specific TBDT sub-family dedicated to the transport of Fe(3+). The region of antigenic hypervariability lies in a separate, external sub-domain, whose structure is conserved in both the F3-3 and F5-1 variants, despite their sequence divergence. We conclude that the antigenic sub-domain has arisen separately as a result of immune selection pressure to distract the immune response from the primary transport function. This would enable FrpB to function as a transporter independently of antibody binding, by using the antigenic sub-domain as a 'molecular decoy' to distract immune surveillance.

A phenomenological intra-laminar plasticity model for FRP composite materials

NASA Astrophysics Data System (ADS)

Zhou, Yinhua; Hou, Chi; Wang, Wenzhi; Zhao, Meiying; Wan, Xiaopeng

2015-07-01

The nonlinearity of fibre-reinforced polymer (FRP) composites have significant effects on the analysis of composite structures. This article proposes a phenomenological intralaminar plasticity model to represent the nonlinearity of FRP composite materials. Based on the model presented by Ladeveze et al., the plastic potential and hardening functions are improved to give a more rational description of phenomenological nonlinearity behavior. A four-parameter hardening model is built to capture important features of the hardening curve and consequently gives the good matching of the experiments. Within the frame of plasticity theory, the detailed constitutive model, the numerical algorithm and the derivation of the tangent stiffness matrix are presented in this study to improve model robustness. This phenomenological model achieved excellent agreement between the experimental and simulation results in element scale respectively for glass fibre-reinforced polymer (GFRP) and carbon fibre-reinforced polymer (CFRP). Moreover, the model is capable of simulating the nonlinear phenomenon of laminates, and good agreement is achieved in nearly all cases.

In-situ monitoring of curing and ageing effects in FRP plates using embedded FBG sensors

NASA Astrophysics Data System (ADS)

Xian, Guijun; Wang, Chuan; Li, Hui

2010-04-01

In recent years, fiber reinforced polymer (FRP) composites have been widely applied in civil engineering for retrofitting or renewal of existing structures. Since FRP composite may degrade when exposed to severe outdoor environments, a serious concern has been raised on its long term durability. In the present study, fiber Bragg grating (FBG) sensors were embedded in glass-, carbon- and basalt-fiber reinforced epoxy based FRP plates with wet lay-up technology, to in-situ monitor the stain changes in FRPs during the curing, and water immersion and freeze-thaw ageing processes. The study demonstrates that the curing of epoxy resin brings in a slight tension strain (e.g., 10 ~ 30 μɛ) along the fiber direction and a high contraction (e.g., ~ 1100μɛ) in the direction perpendicular to the fibers, mainly due to the resin shrinkage. The cured FRP strips were then subjected to distilled water immersion at 80oC and freeze-thaw cycles from -30°C to 30°C. Remarkable strain changes of FRPs due to the variation of the temperatures during freeze-thaw cycles indicate the potential property degradation from fatigue. The maximum strain change is dependent on the fiber types and directions to the fiber. Based on the monitored strain values with temperature change and water uptake content, CTE (coefficient of thermal expansion) and CME (coefficient of moisture expansion) are exactly determined for the FRPs.

Evaluation of wearing surface materials for FRP bridge decks : final report.

DOT National Transportation Integrated Search

2005-07-01

The wearing surface on many fiber reinforced polymer (FRP) composite bridge decks have cracked or delaminated after only a short time in service. Consequently, a set of tests were conducted on four wearing surface products in order to select the mate...

Response of No-Name Creek FRP Bridge to Local Weather : Technical Summary

DOT National Transportation Integrated Search

2012-09-01

Since 1996, over 30 Fiber Reinforced Polymer (FRP) composite bridges have been installed in the United States. Bridge locations are in Kansas, Missouri, New York, Iowa, Colorado, West Virginia, Ohio, California, Idaho, Washington, Pennsylvania, Illin...

Response of No-Name Creek FRP Bridge to Local Weather : Technical Summary

DOT National Transportation Integrated Search

2012-09-01

Since 1996, over 30 Fiber Reinforced Polymer (FRP) composite bridges have been installed : in the United States. Bridge locations are in Kansas, Missouri, New York, Iowa, Colorado, West : Virginia, Ohio, California, Idaho, Washington, Pennsylvania, I...

A state of the art review on reinforced concrete beams with openings retrofitted with FRP

NASA Astrophysics Data System (ADS)

Osman, Bashir H.; Wu, Erjun; Ji, Bohai; S Abdelgader, Abdeldime M.

2016-09-01

The use of externally bonded fiber reinforced polymer (FRP) sheets, strips or steel plates is a modern and convenient way for strengthening of reinforced concrete (RC) beams. Several researches have been carried out on reinforced concrete beams with web openings that strengthened using fiber reinforced polymer composite. Majority of researches focused on shear strengthening compared with flexural strengthening, while others studied the effect of openings on shear and flexural separately with various loading. This paper investigates the impact of more than sixty articles on opening reinforced concrete beams with and without strengthening by fiber reinforcement polymers FRP. Moreover, important practical issues, which are contributed in shear strengthening of beams with different strengthening techniques, such as steel plate and FRP laminate, and detailed with various design approaches are discussed. Furthermore, a simple technique of applying fiber reinforced polymer contributed with steel plate for strengthening the RC beams with openings under different load application is concluded. Directions for future research based on the existing gaps of the present works are presented.

Census study of real-life near-side crashes with modern side airbag-equipped vehicles in the United States.

PubMed

Sunnevång, Cecilia; Sui, Bo; Lindkvist, Mats; Krafft, Maria

2015-01-01

This study aimed to investigate the crash characteristics, injury distribution, and injury mechanisms for Maximum Abbreviated Injury Score (MAIS) 2+ injured belted, near-side occupants in airbag-equipped modern vehicles. Furthermore, differences in injury distribution for senior occupants compared to non-senior occupants was investigated, as well as whether the near-side occupant injury risk to the head and thorax increases or decreases with a neighboring occupant. National Automotive Sampling System's Crashworthiness Data System (NASS-CDS) data from 2000 to 2012 were searched for all side impacts (GAD L&R, all principal direction of force) for belted occupants in modern vehicles (model year > 1999). Rollovers were excluded, and only front seat occupants over the age of 10 were included. Twelve thousand three hundred fifty-four MAIS 2+ injured occupants seated adjacent to the intruding structure (near-side) and protected by at least one deployed side airbag were studied. To evaluate the injury risk influenced by the neighboring occupant, odds ratio with an induced exposure approach was used. The most typical crash occurred either at an intersection or in a left turn where the striking vehicle impacted the target vehicle at a 60 to 70° angle, resulting in a moderate change of velocity (delta-V) and intrusion at the B-pillar. The head, thorax, and pelvis were the most frequent body regions with rib fracture the most frequent specific injury. A majority of the head injuries included brain injuries without skull fracture, and non-senior rather than senior occupants had a higher frequency of head injuries on the whole. In approximately 50% of the cases there was a neighboring occupant influencing injury outcome. Compared to non-senior occupants, the senior occupants sustained a considerably higher rate of thoracic and pelvis injuries, which should be addressed by improved thorax side airbag protection. The influence on near-side occupant injury risk by the neighboring

SeisFlows-Flexible waveform inversion software

NASA Astrophysics Data System (ADS)

Modrak, Ryan T.; Borisov, Dmitry; Lefebvre, Matthieu; Tromp, Jeroen

2018-06-01

SeisFlows is an open source Python package that provides a customizable waveform inversion workflow and framework for research in oil and gas exploration, earthquake tomography, medical imaging, and other areas. New methods can be rapidly prototyped in SeisFlows by inheriting from default inversion or migration classes, and code can be tested on 2D examples before application to more expensive 3D problems. Wave simulations must be performed using an external software package such as SPECFEM3D. The ability to interface with external solvers lends flexibility, and the choice of SPECFEM3D as a default option provides optional GPU acceleration and other useful capabilities. Through support for massively parallel solvers and interfaces for high-performance computing (HPC) systems, inversions with thousands of seismic traces and billions of model parameters can be performed. So far, SeisFlows has run on clusters managed by the Department of Defense, Chevron Corp., Total S.A., Princeton University, and the University of Alaska, Fairbanks.

Meteosat SEVIRI Fire Radiative Power (FRP) products from the Land Surface Analysis Satellite Applications Facility (LSA SAF) - Part 1: Algorithms, product contents and analysis

NASA Astrophysics Data System (ADS)

Wooster, M. J.; Roberts, G.; Freeborn, P. H.; Xu, W.; Govaerts, Y.; Beeby, R.; He, J.; Lattanzio, A.; Mullen, R.

2015-06-01

Characterising changes in landscape scale fire activity at very high temporal resolution is best achieved using thermal observations of actively burning fires made from geostationary Earth observation (EO) satellites. Over the last decade or more, a series of research and/or operational "active fire" products have been developed from these types of geostationary observations, often with the aim of supporting the generation of data related to biomass burning fuel consumption and trace gas and aerosol emission fields. The Fire Radiative Power (FRP) products generated by the Land Surface Analysis Satellite Applications Facility (LSA SAF) from data collected by the Meteosat Second Generation (MSG) Spinning Enhanced Visible and Infrared Imager (SEVIRI) are one such set of products, and are freely available in both near real-time and archived form. Every 15 min, the algorithms used to generate these products identify and map the location of new SEVIRI observations containing actively burning fires, and characterise their individual rates of radiative energy release (fire radiative power; FRP) that is believed proportional to rates of biomass consumption and smoke emission. The FRP-PIXEL product contains the highest spatial resolution FRP dataset, delivered for all of Europe, northern and southern Africa, and part of South America at a spatial resolution of 3 km (decreasing away from the west African sub-satellite point) at the full 15 min temporal resolution. The FRP-GRID product is an hourly summary of the FRP-PIXEL data, produced at a 5° grid cell size and including simple bias adjustments for meteorological cloud cover and for the regional underestimation of FRP caused, primarily, by the non-detection of low FRP fire pixels at SEVIRI's relatively coarse pixel size. Here we describe the enhanced geostationary Fire Thermal Anomaly (FTA) algorithm used to detect the SEVIRI active fire pixels, and detail methods used to deliver atmospherically corrected FRP information

Occupant kinematics and estimated effectiveness of side airbags in pole side impacts using a human FE model with internal organs.

PubMed

Hayashi, Shigeki; Yasuki, Tsuyoshi; Kitagawa, Yuichi

2008-11-01

When a car collides against a pole-like obstacle, the deformation pattern of the vehicle body-side tends to extend to its upper region. A possible consequence is an increase of loading to the occupant thorax. Many studies have been conducted to understand human thoracic responses to lateral loading, and injury criteria have been developed based on the results. However, injury mechanisms, especially those of internal organs, are not well understood. A human body FE model was used in this study to simulate occupant kinematics in a pole side impact. Internal organ parts were introduced into the torso model, including their geometric features, material properties and connections with other tissues. The mechanical responses of the model were validated against PMHS data in the literature. Although injury criterion for each organ has not been established, pressure level and its changes can be estimated from the organ models. Finite element simulations were conducted assuming a case where a passenger vehicle collides against a pole at 29km/h. Occupant kinematics, force-deformation responses and pressure levels were compared between cases with and without side airbag deployment. The results indicated that strain to the ribs and pressure to the organs was smaller with side airbag deployment. The side airbag widened the contact area at the torso, helping to distribute the force to the shoulder, arm and chest. Such distributed force helped generate relatively smaller deformation in the ribs. Furthermore, the side airbag deployment helped restrict the spine displacement. The smaller displacement contributed to lowering the magnitude of contact force between the torso and the door. The study also examined the correlations between the pressure levels in the internal organs, rib deflection, and V*C of chest. The study found that the V*C(t) peak appeared to be synchronized with the organ pressure peak, suggesting that the pressure level of the internal organs could be one possible

Dynamic assessment of reinforced concrete beams repaired with externally bonded FRP sheets

NASA Astrophysics Data System (ADS)

Bonfiglioli, B.; Pascale, G.

2006-01-01

This research deals with RC beams strengthened with FRP. An experimental research is presented which is aimed at evaluating the capability of an experimental modal analysis to assess the stiffness decrease due to damage, as well as the stiffness recovery due to strengthening. Ten beams were tested. All of them were subjected to loading cycles with increasing load levels in order to induce cracking of different severity in them. The beams were then retrofitted by externally bonded FRP sheets. Three types of composites were used. The number of layers was varied, too. Modal tests were carried out after each loading-unloading cycle. The modal frequencies and damping ratios were determined for the first four vibration modes. The results obtained indicate that an experimental modal analysis can give useful information on the severity of damage and the effectiveness of strengthening.

Static-dynamic friction transition of FRP esthetic orthodontic wires on various brackets by suspension-type friction test.

PubMed

Suwa, N; Watari, F; Yamagata, S; Iida, J; Kobayashi, M

2003-11-15

A new testing apparatus for the measurement of frictional properties was designed and the frictional coefficients were obtained and compared with each other in various combinations of brackets and orthodontic wires, including esthetic fiber-reinforced plastic (FRP) wire that was especially designed and manufactured. Three kinds of wires (stainless steel, nickel-titanium, and FRP) and four brackets (single-crystal alumina, polycrystalline alumina, polycarbonate, and stainless steel) were used. The testing was done under dry and wet conditions. The friction testing equipment was designed to attach the bracket to a C-shaped bar suspended with a variable mass, and sliding along a fixed wire. The transition between static and dynamic friction was measured as a breakaway force, with the use of a universal test machine. In addition to material properties, this testing fixture eliminates geometrical factors, such as the rotational moment at the edge of the bracket slot, deflection of the orthodontic wire, and tension of the ligature wire. Nearly ideal frictional properties between materials are obtained. The frictional properties of FRP wire were similar to those of metal wires on all brackets, except the polycrystalline alumina bracket. The frictional coefficient between the polycrystalline ceramic bracket and FRP wire was larger than that of other combinations. There was little difference in frictional coefficients between dry and wet conditions. Copyright 2003 Wiley Periodicals, Inc.

Role of DDC-4/sFRP-4, a secreted frizzled-related protein, at the onset of apoptosis in mammary involution.

PubMed

Lacher, M D; Siegenthaler, A; Jäger, R; Yan, Xi; Hett, S; Xuan, L; Saurer, S; Lareu, R R; Dharmarajan, A M; Friis, R

2003-05-01

Using differential display, we isolated DDC-4, a secreted frizzled-related protein (sFRP), which is induced in the physiological apoptosis of hormonally regulated, reproductive tissues such as mammary gland, prostate, corpus luteum and uterus. The role of this gene in apoptosis was studied in animals overexpressing ectopic DDC-4/sFRP-4. Transgenic mice bearing the DDC-4/sFRP-4 cDNA under the control of the MMTV-LTR promoter showed lactational insufficiency and many apoptotic cells in the alveoli between day 19 of pregnancy and day 4 of lactation as demonstrated by TUNEL reaction and the presence of activated caspase-3. We performed a PKB/Akt kinase assay and studied several of its substrates using phosphorylation-specific antibodies to show reduced phosphorylation in PKB/Akt itself, as well as in glycogen synthetase kinase-3beta (GSK-3beta), BAD, and Forkhead. Taken together, our results show a role for DDC-4/sFRP-4 in abrogating an epithelial cell survival pathway at the onset of mammary gland involution.

Photogrammetric Measurements of CEV Airbag Landing Attenuation Systems

NASA Technical Reports Server (NTRS)

Barrows, Danny A.; Burner, Alpheus W.; Berry, Felecia C.; Dismond, Harriett R.; Cate, Kenneth H.

2008-01-01

High-speed photogrammetric measurements are being used to assess the impact dynamics of the Orion Crew Exploration Vehicle (CEV) for ground landing contingency upon return to earth. Test articles representative of the Orion capsule are dropped at the NASA Langley Landing and Impact Research (LandIR) Facility onto a sand/clay mixture representative of a dry lakebed from elevations as high as 62 feet (18.9 meters). Two different types of test articles have been evaluated: (1) half-scale metal shell models utilized to establish baseline impact dynamics and soil characterization, and (2) geometric full-scale drop models with shock-absorbing airbags which are being evaluated for their ability to cushion the impact of the Orion CEV with the earth s surface. This paper describes the application of the photogrammetric measurement technique and provides drop model trajectory and impact data that indicate the performance of the photogrammetric measurement system.

Effects of child age and body size on serious injury from passenger air-bag presence in motor vehicle crashes.

PubMed

Newgard, Craig D; Lewis, Roger J

2005-06-01

Current recommendations regarding children traveling in passenger vehicles equipped with passenger air bags are based, in part, on evidence that the air-bag-related risk of injury and death is higher for children < or =12 years of age. However, the age or body size required to allow a child to be seated safely in front of a passenger air bag is unknown. To evaluate specific cutoff points for age, height, and weight as effect modifiers of the association between the presence of a passenger air bag and serious injury among children involved in motor vehicle crashes (MVCs), while controlling for important crash factors. A national population-based cohort of children involved in MVCs and included in the National Automotive Sampling System (NASS) Crashworthiness Data System (CDS) database from 1995 to 2002 was studied. NASS CDS clusters, strata, and weights were included in all analyses. Children 0 to 18 years of age involved in MVCs and seated in the right front passenger seat. Serious injury, defined as an Abbreviated Injury Scale score of > or =3 for any body region. A total of 3790 patients (1 month to 18 years of age) were represented in the NASS CDS database during the 8-year period. Sixty children (1.6%) were seriously injured (Abbreviated Injury Scale score of > or =3). Among age, height, and weight, age of 0 to 14 years (versus 15-18 years) was the only consistent effect modifier of the association between air-bag presence (or air-bag deployment) and serious injury, particularly for crashes with a moderate probability of injury. In analyses stratified according to age and adjusted for important crash factors, children 0 to 14 years of age involved in frontal collisions seemed to be at increased risk of serious injury from air-bag presence (odds ratio [OR]: 2.66; 95% confidence interval [CI]: 0.23-30.9) and deployment (OR: 6.13; 95% CI: 0.30-126), although these values did not reach statistical significance. Among children 15 to 18 years of age involved in

Bridge-in-a-backpack(TM) task 3.3 : investigate soil-structure interaction-modeling and experimental results of concrete filled FRP tube arches.

DOT National Transportation Integrated Search

2015-12-01

This report includes fulfillment of Task 3.3 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 3 is an investigation of soil-structure interaction for the FRP tubes. Task 3.3 is the : modeling ...

SeisComP 3 - Where are we now?

NASA Astrophysics Data System (ADS)

Saul, Joachim; Becker, Jan; Hanka, Winfried; Heinloo, Andres; Weber, Bernd

2010-05-01

The seismological software SeisComP has evolved within the last approximately 10 years from a pure acquisition modules to a fully featured real-time earthquake monitoring software. The now very popular SeedLink protocol for seismic data transmission has been the core of SeisComP from the very beginning. Later additions included simple, purely automatic event detection, location and magnitude determination capabilities. Especially within the development of the 3rd-generation SeisComP, also known as "SeisComP 3", automatic processing capabilities have been augmented by graphical user interfaces for vizualization, rapid event review and quality control. Communication between the modules is achieved using a a TCP/IP infrastructure that allows distributed computing and remote review. For seismological metadata exchange export/import to/from QuakeML is avalable, which also provides a convenient interface with 3rd-party software. SeisComP is the primary seismological processing software at the GFZ Potsdam. It has also been in use for years in numerous seismic networks in Europe and, more recently, has been adopted as primary monitoring software by several tsunami warning centers around the Indian Ocean. In our presentation we describe the current status of development as well as future plans. We illustrate its possibilities by discussing different use cases for global and regional real-time earthquake monitoring and tsunami warning.

Design for FRP systems for strengthening concrete girders in shear : status letter.

DOT National Transportation Integrated Search

2010-09-24

This is to let you know that we have completed our NCHRP 12-75 project entitled DESIGN OF : FRP SYSTEMS FOR STRENGTHENING CONCRETE GIRDERS IN SHEAR and submitted the final : report on June 7, 2010. The report is undergoing final editorial revis...

ASSESSMENT OF STYRENE EMISSION CONTROLS FOR FRP/C AND BOAT BUILDING INDUSTRIES

EPA Science Inventory

The report gives results of an evaluation of several conventional and novel emission control technologies that have been used or could be used to treat styrene emissions from open molding processes in fiberglass-reinforced plastics/composites (FRP/C) and fiberglass boat building ...

High-temperature solid electrolyte interphases (SEI) in graphite electrodes

NASA Astrophysics Data System (ADS)

Rodrigues, Marco-Tulio F.; Sayed, Farheen N.; Gullapalli, Hemtej; Ajayan, Pulickel M.

2018-03-01

Thermal fragility of the solid electrolyte interphase (SEI) is a major source of performance decay in graphite anodes, and efforts to overcome the issues offered by extreme environments to Li-ion batteries have had limited success. Here, we demonstrate that the SEI can be extensively reinforced by carrying the formation cycles at elevated temperatures. Under these conditions, decomposition of the ionic liquid present in the electrolyte favored the formation of a thicker and more protective layer. Cells in which the solid electrolyte interphase was cast at 90 °C were significantly less prone to self-discharge when exposed to high temperature, with no obvious damages to the formed SEI. This additional resilience was accomplished at the expense of rate capability, as charge transfer became growingly inefficient in these systems. At slower rates, however, cells that underwent SEI formation at 90 °C presented superior performances, as a result of improved Li+ transport through the SEI, and optimal wetting of graphite by the electrolyte. This work analyzes different graphite hosts and ionic liquids, showing that this effect is more pervasive than anticipated, and offering the unique perspective that, for certain systems, temperature can actually be an asset for passivation.

A review of the application Acoustic Emission (AE) incorporating mechanical approach to monitor Reinforced concrete (RC) strengthened with Fiber Reinforced Polymer (FRP) properties under fracture

NASA Astrophysics Data System (ADS)

Syed Mazlan, S. M. S.; Abdullah, S. R.; Shahidan, S.; Noor, S. R. Mohd

2017-11-01

Concrete durability may be affected by so many factors such as chemical attack and weathering action that reduce the performance and the service life of concrete structures. Low durability Reinforced concrete (RC) can be greatly improved by using Fiber Reinforce Polymer (FRP). FRP is a commonly used composite material for repairing and strengthening RC structures. A review on application of Acoustic Emission (AE) techniques of real time monitoring for various mechanical tests for RC strengthened with FRP involving four-point bending, three-point bending and cyclic loading was carried out and discussed in this paper. Correlations between each AE analyses namely b-value, sentry and intensity analysis on damage characterization also been critically reviewed. From the review, AE monitoring involving RC strengthened with FRP using b-value, sentry and intensity analysis are proven to be successful and efficient method in determining damage characterization. However, application of AE analysis using sentry analysis is still limited compared to b-value and intensity analysis in characterizing damages especially for RC strengthened with FRP specimen.

Repair of impact damaged utility poles with fiber reinforced polymers (FRP), phase II.

DOT National Transportation Integrated Search

2015-06-01

Vehicle collisions with steel or aluminum utility poles are common occurrences that yield substantial but often repairable : damage. This project investigates the use of a fiber-reinforced polymer (FRP) composite system for in situ repair that : mini...

Behavior of Concrete Cylinders Strengthened with a Basalt-FRP and Subjected to Mechanical Loads and Elevated Temperatures

NASA Astrophysics Data System (ADS)

Tulendinov, T.; Zesers, A.; Tamužs, V.

2017-09-01

Concrete samples were manufactured and strengthened with a basalt FRP (BFRP) using two kinds of winding patterns (spiral and tight). The efficiency of common and temperature-resistant epoxy binders were studied. Some of the samples were encased in an external concrete shell for an additional protection of the FRP reinforcement during heating. Both plain and polypropylene-microfiber-reinforced concretes were used for the external casing. Stress-strain relations of the samples before and after heating were obtained. The effects of high temperatures on the integrity of concrete samples with a BFRP reinforcement was investigated.

Behavior of hollow-core FRP-concrete-steel columns subjected to cyclic axial compression.

DOT National Transportation Integrated Search

2014-08-01

This report presents the results of an experimental study that was conducted to investigate the effects of key parameters on the compressive behavior of fiber reinforced polymer (FRP)-concrete-steel double-skin tubular columns (FSDT). Hybrid FSDT col...

Review on modeling of the anode solid electrolyte interphase (SEI) for lithium-ion batteries

NASA Astrophysics Data System (ADS)

Wang, Aiping; Kadam, Sanket; Li, Hong; Shi, Siqi; Qi, Yue

2018-03-01

A passivation layer called the solid electrolyte interphase (SEI) is formed on electrode surfaces from decomposition products of electrolytes. The SEI allows Li+ transport and blocks electrons in order to prevent further electrolyte decomposition and ensure continued electrochemical reactions. The formation and growth mechanism of the nanometer thick SEI films are yet to be completely understood owing to their complex structure and lack of reliable in situ experimental techniques. Significant advances in computational methods have made it possible to predictively model the fundamentals of SEI. This review aims to give an overview of state-of-the-art modeling progress in the investigation of SEI films on the anodes, ranging from electronic structure calculations to mesoscale modeling, covering the thermodynamics and kinetics of electrolyte reduction reactions, SEI formation, modification through electrolyte design, correlation of SEI properties with battery performance, and the artificial SEI design. Multi-scale simulations have been summarized and compared with each other as well as with experiments. Computational details of the fundamental properties of SEI, such as electron tunneling, Li-ion transport, chemical/mechanical stability of the bulk SEI and electrode/(SEI/) electrolyte interfaces have been discussed. This review shows the potential of computational approaches in the deconvolution of SEI properties and design of artificial SEI. We believe that computational modeling can be integrated with experiments to complement each other and lead to a better understanding of the complex SEI for the development of a highly efficient battery in the future.

76 FR 72729 - SEI Investments Management Corporation, et al.

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-25

...] SEI Investments Management Corporation, et al. November 18, 2011. AGENCY: Securities and Exchange... Application: Applicants request an order to permit open-end management investment companies relying on rule 12d1-2 under the Act to invest in certain financial instruments. Applicants: SEI Investments Management...

Disbond detection with piezoelectric wafer active sensors in RC structures strengthened with FRP composite overlays

NASA Astrophysics Data System (ADS)

Giurgiutiu, Victor; Harries, Kent; Petrou, Michael; Bost, Joel; Quattlebaum, Josh B.

2003-12-01

The capability of embedded piezoelectric wafer active sensors (PWAS) to perform in-situ nondestructive evaluation (NDE) for structural health monitoring (SHM) of reinforced concrete (RC) structures strengthened with fiber reinforced polymer (FRP) composite overlays is explored. First, the disbond detection method were developed on coupon specimens consisting of concrete blocks covered with an FRP composite layer. It was found that the presence of a disbond crack drastically changes the electromechanical (E/M) impedance spectrum measured at the PWAS terminals. The spectral changes depend on the distance between the PWAS and the crack tip. Second, large scale experiments were conducted on a RC beam strengthened with carbon fiber reinforced polymer (CFRP) composite overlay. The beam was subject to an accelerated fatigue load regime in a three-point bending configuration up to a total of 807,415 cycles. During these fatigue tests, the CFRP overlay experienced disbonding beginning at about 500,000 cycles. The PWAS were able to detect the disbonding before it could be reliably seen by visual inspection. Good correlation between the PWAS readings and the position and extent of disbond damage was observed. These preliminary results demonstrate the potential of PWAS technology for SHM of RC structures strengthened with FRP composite overlays.

Highly accelerated lifetime for externally applied bond critical fiber-reinforced polymer (FRP) infrastructure materials.

DOT National Transportation Integrated Search

2014-03-01

This report describes a research project to investigate accelerated aging protocols for fiber-reinforced : polymer (FRP) reinforcement of concrete. This research was conducted in three stages. In the first : stage, various spectroscopic techniques we...

Fire Radiative Power (FRP)-based Emission Factors of PM2.5, CO and NOX for Remote Sensing of Biomass Burning Emissions

NASA Astrophysics Data System (ADS)

Karandana Gamalathge, T. D.; Chen, L. W. A.

2015-12-01

Large-scale biomass burning such as forest fires represents an important and yet uncertain source of air pollutants and greenhouse gases on a global scale. Due to the highly accidental nature of forest fires, satellite remote sensing could be a promising method to develop regional and global fire emission inventories on a real-time basis. Reliable fire radiative power (FRP)-based fuel consumption and emission factors are critical in this approach. In an attempt to obtain the information, laboratory combustion experiments were conducted to simultaneously monitor FRP, fuel consumption, and emissions of fine particulate matter (PM2.5), carbon monoxide (CO), and reactive nitrogen oxides (NO and NO2). FRP were quantified using temperature-resolved values from a thermal imager instead of conventionally used average temperature, as the former provides more realistic estimates. For dry Ponderosa pine branches, a common fuel in the Sierra Nevada, a strong correlation (r2 ~ 0.8) between FRP and the mass reduction rate (MRR) was found. This led to a radiative energy yield (REY) of 8.5 ± 1.2 MJ/kg, assuming blackbody radiation and a flame emissivity of 0.5. Mass-based emission factors were determined with the carbon balance approach. Considering the ratio of mass-based emission factors and the REY, FRP-based emission factors: PM2.5: 11 g/MJ, CO: 8.0 g/MJ, NO: 0.33 g/MJ, and NO2: 0.07 g/MJ were quantified. The application of this approach to other fuel types and uncertainties in the measurements will be discussed.

Secreted Frizzled-related protein 1 (sFRP1) regulates spermatid adhesion in the testis via dephosphorylation of focal adhesion kinase and the nectin-3 adhesion protein complex

PubMed Central

Wong, Elissa W. P.; Lee, Will M.; Cheng, C. Yan

2013-01-01

Development of spermatozoa in adult mammalian testis during spermatogenesis involves extensive cell migration and differentiation. Spermatogonia that reside at the basal compartment of the seminiferous epithelium differentiate into more advanced germ cell types that migrate toward the apical compartment until elongated spermatids are released into the tubule lumen during spermiation. Apical ectoplasmic specialization (ES; a testis-specific anchoring junction) is the only cell junction that anchors and maintains the polarity of elongating/elongated spermatids (step 8–19 spermatids) in the epithelium. Little is known regarding the signaling pathways that trigger the disassembly of the apical ES at spermiation. Here, we show that secreted Frizzled-related protein 1 (sFRP1), a putative tumor suppressor gene that is frequently down-regulated in multiple carcinomas, is a crucial regulatory protein for spermiation. The expression of sFRP1 is tightly regulated in adult rat testis to control spermatid adhesion and sperm release at spermiation. Down-regulation of sFRP1 during testicular development was found to coincide with the onset of the first wave of spermiation at approximately age 45 d postpartum, implying that sFRP1 might be correlated with elongated spermatid adhesion conferred by the apical ES before spermiation. Indeed, administration of sFRP1 recombinant protein to the testis in vivo delayed spermiation, which was accompanied by down-regulation of phosphorylated (p)-focal adhesion kinase (FAK)-Tyr397 and retention of nectin-3 adhesion protein at the apical ES. To further investigate the functional relationship between p-FAK-Tyr397 and localization of nectin-3, we overexpressed sFRP1 using lentiviral vectors in the Sertoli-germ cell coculture system. Consistent with the in vivo findings, overexpression of sFRP1 induced down-regulation of p-FAK-Tyr397, leading to a decline in phosphorylation of nectin-3. In summary, this report highlights the critical role of sFRP

Hybrid FRP-concrete bridge deck system final report I : development and system performance validation.

DOT National Transportation Integrated Search

2009-10-01

In this study, the concept of the hybrid FRP-concrete structural systems was applied to both bridge : superstructure and deck systems. Results from the both experimental and computational analysis for : both the hybrid bridge superstructure and deck ...

Development of load and resistance factor design for FRP strengthening of reinforced concrete bridges.

DOT National Transportation Integrated Search

2006-05-01

Externally bonded fiber reinforced polymer (FRP) composites are an increasingly adopted technology for the renewal of existing concrete structures. In order to encourage the further use of these materials, a design code is needed that considers the i...

An Experimental Study on Shrinkage Strains of Normal-and High-Strength Concrete-Filled Frp Tubes

NASA Astrophysics Data System (ADS)

Vincent, Thomas; Ozbakkaloglu, Togay

2017-09-01

It is now well established that concrete-filled fiber reinforced polymer (FRP) tubes (CFFTs) are an attractive construction technique for new columns, however studies examining concrete shrinkage in CFFTs remain limited. Concrete shrinkage may pose a concern for CFFTs, as in these members the curing of concrete takes place inside the FRP tube. This paper reports the findings from an experimental study on concrete shrinkage strain measurements for CFFTs manufactured with normal- and high-strength concrete (NSC and HSC). A total of 6 aramid FRP (AFRP)-confined concrete specimens with circular cross-sections were manufactured, with 3 specimens each manufactured using NSC and HSC. The specimens were instrumented with surface and embedded strain gauges to monitor shrinkage development of exposed concrete and concrete sealed inside the CFFTs, respectively. All specimens were cylinders with a 152 mm diameter and 305 mm height, and their unconfined concrete strengths were 44.8 or 83.2 MPa. Analysis of the shrinkage measurements from concrete sealed inside the CFFTs revealed that embedment depth and concrete compressive strength only had minor influences on recorded shrinkage strains. However, an analysis of shrinkage measurements from the exposed concrete surface revealed that higher amounts of shrinkage can occur in HSC. Finally, it was observed that shrinkage strains are significantly higher for concrete exposed at the surface compared to concrete sealed inside the CFFTs.

Strengthening of Route 378 bridge over Wynantskill Creek in New York using FRP laminates

DOT National Transportation Integrated Search

2001-03-01

This report describes application of Fiber-Reinforced Polymer (FRP) composite laminates to strengthen an aging reinforced-concrete T-beam bridge in South Troy, Rensselaer County, New York. Leakage at the end joints of this single-span structure led t...

Performance range of SMA actuator wires and SMA-FRP structure in terms of manufacturing, modeling and actuation

NASA Astrophysics Data System (ADS)

Hübler, M.; Gurka, M.; Schmeer, S.; Breuer, U. P.

2013-09-01

In this contribution we present a comprehensive theoretical and experimental description of an active shape memory alloy (SMA) fiber reinforced composite (FRP) hybrid structure. The major influences on actuation performance arising from variations in the design and manufacturing process are discussed, utilizing a new phenomenological model to describe the actuating SMA material. The different material properties for the activated, respective the unactivated, SMA as well as the influence of different loading conditions or pre-treatment of the material are taken into account in this model. To validate our material model we performed new actuation experiments with an exemplary SMA-FRP structure, which we compared to finite element (FE) simulation results. Our FE-model is based on a material model for the actuating SMA elements derived from experiments and data on the actual microscopic geometry of the hybrid composite. Therefore it is able to predict very precisely the actuation behavior of a typical FRP structure for industrial use cases: a thin walled CFRP sheet with SMA wires attached to the top for performing a bending motion with a maximum deflection of approx. 25% of its length.

Cross-correlation between the controlled collision environment and real-world motor vehicle collisions: Evaluating the protection of the thoracic side airbag.

PubMed

Gaylor, Luke; Junge, Mirko; Abanteriba, Sylvester

2018-05-19

Thoracic side airbags (tSABs) were integrated into the vehicle fleet to attenuate and distribute forces on the occupant's chest and abdomen, dissipate the impact energy, and move the occupant away from the intruding structure, all of which reduce the risk of injury. This research piece investigates and evaluates the safety performance of the airbag unit by cross-correlating data from a controlled collision environment with field data. We focus exclusively on vehicle-vehicle lateral impacts from the NHTSA's Vehicle Crash Test Database and NASS-CDS database, which are replicated in the controlled environment by the (crabbed) barrier impact. Similar collisions with and without seat-embedded tSABs are matched to each other and the injury risks are compared. Results indicated that dummy-based thoracic injury metrics were significantly lower with tSAB exposure (P <.001). Yet, when the controlled collision environment data were cross-correlated with NASS-CDS collisions, deployment of the tSAB indicated no association with thoracic injury (tho. MAIS 2+ unadjusted relative risk [RR] = 1.14; 90% confidence interval [CI], 0.80-1.62; tho. MAIS 3+ unadjusted RR = 1.12; 90% CI, 0.76-1.65). The data from the controlled collision environment indicated an unequivocal benefit provided by the thoracic side airbag for the crash dummy; however, the real-world collisions demonstrate that no benefit is provided to the occupant. This has resulted from a noncorrelation between the crash test/dummy-based design taking the abstracting process too far to represent the real-world collision scenario.

Airbags to Martian Landers: Analyses at Sandia National Laboratories

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

Gwinn, K.W.

1994-03-01

A new direction for the national laboratories is to assist US business with research and development, primarily through cooperative research and development agreements (CRADAs). Technology transfer to the private sector has been very successful as over 200 CRADAs are in place at Sandia. Because of these cooperative efforts, technology has evolved into some new areas not commonly associated with the former mission of the national laboratories. An example of this is the analysis of fabric structures. Explicit analyses and expertise in constructing parachutes led to the development of a next generation automobile airbag; which led to the construction, testing, andmore » analysis of the Jet Propulsion Laboratory Mars Environmental Survey Lander; and finally led to the development of CAD based custom garment designs using 3D scanned images of the human body. The structural analysis of these fabric structures is described as well as a more traditional example Sandia with the test/analysis correlation of the impact of a weapon container.« less

ADDENDUM TO ASSESSMENT OF STYRENE EMISSION CONTROLS FOR FRP/C AND BOAT BUILDING INDUSTRIES

EPA Science Inventory

This report is an addendum to a 1996 report, Assessment of Styrene Emission Controls for FRP/C and Boat Building Industries. It presents additional evaluation of the biological treatment of styrene emissions, Dow Chemical Company's Sorbathene solvent vapor recovery system, Occupa...

Space exploration initiative (SEI) logistics support lessons from the DoD

NASA Astrophysics Data System (ADS)

Cox, John R.; McCoy, Walbert G.; Jenkins, Terence

Proven and innovative logistics management approaches and techniques used for developing and supporting DoD and Strategic Defense Initiative Office (SDIO) systems are described on the basis of input from DoD to the SEI Synthesis Group; SDIO-developed logistics initiatives, innovative tools, and methodologies; and logistics planning support provided to the NASA/Johnson Planet Surface System Office. The approach is tailored for lunar/Martian surface operations, and provides guidelines for the development and management of a crucial element of the SEI logistics support program. A case study is presented which shows how incorporation of DoD's proven and innovative logistics management approach, tools, and techniques can substantially benefit early logistics planning for SEI, while also implementing many of DoD's recommendations for SEI.

Pro-Inflammatory wnt5a and Anti-Inflammatory sFRP5 Are Differentially Regulated by Nutritional Factors in Obese Human Subjects

PubMed Central

Schulte, Dominik M.; Müller, Nike; Neumann, Katrin; Oberhäuser, Frank; Faust, Michael; Güdelhöfer, Heike; Brandt, Burkhard; Krone, Wilhelm; Laudes, Matthias

2012-01-01

Background Obesity is associated with macrophage infiltration of adipose tissue. These inflammatory cells affect adipocytes not only by classical cytokines but also by the secreted glycopeptide wnt5a. Healthy adipocytes are able to release the wnt5a inhibitor sFRP5. This protective effect, however, was found to be diminished in obesity. The aim of the present study was to examine (1) whether obese human subjects exhibit increased serum concentrations of wnt5a and (2) whether wnt5a and/or sFRP5 serum concentrations in obese subjects can be influenced by caloric restriction. Methodology 23 obese human subjects (BMI 44.1±1.1 kg/m2) and 12 age- and sex-matched lean controls (BMI 22.3±0.4 kg/m2) were included in the study. Obese subjects were treated with a very low-calorie diet (approximately 800 kcal/d) for 12 weeks. Body composition was assessed by impedance analysis, insulin sensitivity was estimated by HOMA-IR and the leptin-to-adiponectin ratio and wnt5a and sFRP5 serum concentrations were measured by ELISA. sFRP5 expression in human adipose tissue biopsies was further determined on protein level by immunohistology. Principal Findings Pro-inflammatory wnt5a was not measurable in any serum sample of lean control subjects. In patients with obesity, however, wnt5a became significantly detectable consistent with low grade inflammation in such subjects. Caloric restriction resulted in a weight loss from 131.9±4.0 to 112.3±3.2 kg in the obese patients group. This was accompanied by a significant decrease of HOMA-IR and leptin-to-adiponectin ratio, indicating improved insulin sensitivity. Interestingly, these metabolic improvements were associated with a significant increase in serum concentrations of the anti-inflammatory factor and wnt5a-inhibitor sFRP5. Conclusions/Significance Obesity is associated with elevated serum levels of pro-inflammatory wnt5a in humans. Furthermore, caloric restriction beneficially affects serum concentrations of anti-inflammatory sFRP5

Assessment of mechanically fastened fiber reinforced polymer (MF-FRP) strips for extending bridge service life.

DOT National Transportation Integrated Search

2015-03-01

The enhancement of load rating concrete structures by the installation of Fiber reinforced : polymer strips (FRP) is becoming a preferred short-term action. The addition of supplemental : tensile capacity to concrete beams by applying high tensile st...

Using the Fire Weather Index (FWI) to improve the estimation of fire emissions from fire radiative power (FRP) observations

NASA Astrophysics Data System (ADS)

Di Giuseppe, Francesca; Rémy, Samuel; Pappenberger, Florian; Wetterhall, Fredrik

2018-04-01

The atmospheric composition analysis and forecast for the European Copernicus Atmosphere Monitoring Services (CAMS) relies on biomass-burning fire emission estimates from the Global Fire Assimilation System (GFAS). The GFAS is a global system and converts fire radiative power (FRP) observations from MODIS satellites into smoke constituents. Missing observations are filled in using persistence, whereby observed FRP values from the previous day are progressed in time until a new observation is recorded. One of the consequences of this assumption is an increase of fire duration, which in turn translates into an increase of emissions estimated from fires compared to what is available from observations. In this study persistence is replaced by modelled predictions using the Canadian Fire Weather Index (FWI), which describes how atmospheric conditions affect the vegetation moisture content and ultimately fire duration. The skill in predicting emissions from biomass burning is improved with the new technique, which indicates that using an FWI-based model to infer emissions from FRP is better than persistence when observations are not available.

Evaluation of the SEI using a multilayer spectroscopic ellipsometry model

DOE PAGES

Dufek, Eric J.

2014-08-28

A multilayer spectroscopic ellipsometry (SE) model has been developed to characterize SEI formation. The model, which consists of two Cauchy layers, is constructed with an inner layer meant to model primarily inorganic compounds adjacent to an electrode and an outer layer which mirrors polymeric, organic constituents on the exterior of the SEI. Comparison of 1:1 EC:EMC and 1:4 EC:EMC with 1.0 M LiPF₆ shows distinct differences in the two modeled layers. The data suggest that the thickness of both layers change over a wide potential range. These changes have been linked with other reports on the growth of the SEI.

Development of Embedded Vascular Networks in FRP for Active/Passive Thermal Management

DTIC Science & Technology

2015-04-01

Passive Thermal Management Katarzyna...To) 30 September 2012 – 31 December 2014 4. TITLE AND SUBTITLE Development of Embedded Vascular Networks in FRP for Active/ Passive Thermal Management   5a...Active/ Passive   Thermal   Management   Reference:       EOARD  grant  (FA8655-­‐12-­‐1-­‐2144)   Investigators:    

Passenger head in impact with frontal airbag in OOP postures

NASA Astrophysics Data System (ADS)

Ovidiu Soica, Adrian; Toganel, George-Radu

2017-10-01

Road accidents represent an aspect of road traffic that may lead negative consequences. In order to solve the problems associated with such events, interdisciplinary knowledge is called for, complex teams of engineers, doctors, lawyers, experts working together in order to reduce the severity of such events. Road safety is a continuous concern for both experts and various government organizations with the aim of protecting the lives of the participants in traffic. It has been estimated that the costs of traffic accidents account for 1-3% of a country GDP, depending on the level of country development [26]. In this paper we analyze a particular class of cases of injuries caused to passengers caused by the inflation of the frontal airbag when they are with the passenger out of position. Head kinematics, accelerations, as well as the severity of injuries expressed by HIC, as related to the AIS scale have been analysed.

SEIS-PROV: Practical Provenance for Seismological Data

NASA Astrophysics Data System (ADS)

Krischer, L.; Smith, J. A.; Tromp, J.

2015-12-01

It is widely recognized that reproducibility is crucial to advance science, but at the same time it is very hard to actually achieve. This results in it being recognized but also mostly ignored by a large fraction of the community. A key ingredient towards full reproducibility is to capture and describe the history of data, an issue known as provenance. We present SEIS-PROV, a practical format and data model to store provenance information for seismological data. In a seismological context, provenance can be seen as information about the processes that generated and modified a particular piece of data. For synthetic waveforms the provenance information describes which solver and settings therein were used to generate it. When looking at processed seismograms, the provenance conveys information about the different time series analysis steps that led to it. Additional uses include the description of derived data types, such as cross-correlations and adjoint sources, enabling their proper storage and exchange. SEIS-PROV is based on W3C PROV (http://www.w3.org/TR/prov-overview/), a standard for generic provenance information. It then applies an additional set of constraints to make it suitable for seismology. We present a definition of the SEIS-PROV format, a way to check if any given file is a valid SEIS-PROV document, and two sample implementations: One in SPECFEM3D GLOBE (https://geodynamics.org/cig/software/specfem3d_globe/) to store the provenance information of synthetic seismograms and another one as part of the ObsPy (http://obspy.org) framework enabling automatic tracking of provenance information during a series of analysis and transformation stages. This, along with tools to visualize and interpret provenance graphs, offers a description of data history that can be readily tracked, stored, and exchanged.

FRP MODEL - VERSION 1.0 FOR ESTIMATING STYRENE EMISSIONS FROM FIBER-REINFORCED PLASTICS FABRICATION PROCESSES

EPA Science Inventory

This software estimates styrene emissions from the manufacture of fiber-reinforced plastics/composite (FRP/C) products. In using the model, the user first chooses the appropriate process: gel coating, resin sprayup, hand layup, etc. Choosing a process will cause the 'baseline' in...

Design equations for the assessment and FRP-strengthening of reinforced rectangular concrete columns under combined biaxial bending and axial loads

NASA Astrophysics Data System (ADS)

Alessandri, S.; Monti, G.

2008-05-01

A simple procedure is proposed for the assessment of reinforced rectangular concrete columns under combined biaxial bending and axial loads and for the design of a correct amount of FRP-strengthening for underdesigned concrete sections. Approximate closed-form equations are developed based on the load contour method originally proposed by Bresler for reinforced concrete sections. The 3D failure surface is approximated along its contours, at a constant axial load, by means of equations given as the sum of the acting/resisting moment ratio in the directions of principal axes of the sections, raised to a power depending on the axial load, the steel reinforcement ratio, and the section shape. The method is extended to FRP-strengthened sections. Moreover, to make it possible to apply the load contour method in a more practical way, simple closed-form equations are developed for rectangular reinforced concrete sections with a two-way steel reinforcement and FRP strengthenings on each side. A comparison between the approach proposed and the fiber method (which is considered exact) shows that the simplified equations correctly represent the section interaction diagram.

SEI Approach to Harmonization

DTIC Science & Technology

2008-07-18

PAs and PLA ISO 15504 and ISO 12207 COBIT EFQM ISO 9001 Improvement Method Elements Change management techniques: IDEAL and Six Sigma...Multimodel Improvement in Practice 12 SEI Webinar Series Northrop Grumman Mission Systems • CMMI, Six Sigma, ISO , KM • ―.. accelerate achievement of Levels...CMMI, ITIL, ISO 9001, P-CMM  ―Integrated Quality Mgmt System‖ • ―…development center…reduce[d]...in-process failure costs...5 to 1%...‖ Wipro • ISO

Development of FRP composite structural biomaterials: ultimate strength of the fiber/matrix interfacial bond in in vivo simulated environments.

PubMed

Latour, R A; Black, J

1992-05-01

Fiber reinforced polymer (FRP) composites are being developed as alternatives to metals for structural orthopedic implant applications. FRP composite fracture behavior and environmental interactions are distinctly different from those which occur in metals. These differences must be accounted for in the design and evaluation of implant performance. Fiber/matrix interfacial bond strength in a FRP composite is known to strongly influence fracture behavior. The interfacial bond strength of four candidate fiber/matrix combinations (carbon fiber/polycarbonate, carbon fiber/polysulfone, polyaramid fiber/polycarbonate, polyaramid fiber/polysulfone) were investigated at 37 degrees C in dry and in vivo simulated (saline, exudate) environments. Ultimate bond strength was measured by a single fiber-microdroplet pull-out test. Dry bond strengths were significantly decreased following exposure to either saline or exudate with bond strength loss being approximately equal in both the saline and exudate. Bond strength loss is attributed to the diffusion of water and/or salt ions into the sample and their interaction with interfacial bonding. Because bond degradation is dependent upon diffusion, diffusional equilibrium must be obtained in composite test samples before the full effect of the test environment upon composite mechanical behavior can be determined.

Advancing Cyber Intelligence Practices Through the SEI’s Consortium

DTIC Science & Technology

2015-01-27

blogsjsocial media Extracurricular Activities Vu lnerabilities from these individuals roles with non-target entities-non-profits, activist groups, or...information to identify, track, and predict cyber capabilities, intentions, and activities to offer courses of action that enhance decision making 7 SEI...8 SEI Webinar Series January 27, 2015 © 2015 Carnegie Mellon University Offerings Steering Committee: Guide Consortium activities and plan for

Concrete Infill Monitoring in Concrete-Filled FRP Tubes Using a PZT-Based Ultrasonic Time-of-Flight Method.

PubMed

Luo, Mingzhang; Li, Weijie; Hei, Chuang; Song, Gangbing

2016-12-07

Concrete-filled fiber-reinforced polymer tubes (CFFTs) have attracted interest for their structural applications in corrosive environments. However, a weak interfacial strength between the fiber-reinforced polymer (FRP) tube and the concrete infill may develop due to concrete shrinkage and inadequate concrete compaction during concrete casting, which will destroy the confinement effect and thereby reduce the load bearing capacity of a CFFT. In this paper, the lead zirconate titanate (PZT)-based ultrasonic time-of-flight (TOF) method was adopted to assess the concrete infill condition of CFFTs. The basic idea of this method is that the velocity of the ultrasonic wave propagation in the FRP material is about half of that in concrete material. Any voids or debonding created along the interface between the FRP tube and the concrete will delay the arrival time between the pairs of PZT transducers. A comparison of the arrival times of the PZT pairs between the intact and the defected CFFT was made to assess the severity of the voids or the debonding. The feasibility of the methodology was analyzed using a finite-difference time-domain-based numerical simulation. Experiments were setup to validate the numerical results, which showed good agreement with the numerical findings. The results showed that the ultrasonic time-of-flight method is able to detect the concrete infill condition of CFFTs.

Concrete Infill Monitoring in Concrete-Filled FRP Tubes Using a PZT-Based Ultrasonic Time-of-Flight Method

PubMed Central

Luo, Mingzhang; Li, Weijie; Hei, Chuang; Song, Gangbing

2016-01-01

Concrete-filled fiber-reinforced polymer tubes (CFFTs) have attracted interest for their structural applications in corrosive environments. However, a weak interfacial strength between the fiber-reinforced polymer (FRP) tube and the concrete infill may develop due to concrete shrinkage and inadequate concrete compaction during concrete casting, which will destroy the confinement effect and thereby reduce the load bearing capacity of a CFFT. In this paper, the lead zirconate titanate (PZT)-based ultrasonic time-of-flight (TOF) method was adopted to assess the concrete infill condition of CFFTs. The basic idea of this method is that the velocity of the ultrasonic wave propagation in the FRP material is about half of that in concrete material. Any voids or debonding created along the interface between the FRP tube and the concrete will delay the arrival time between the pairs of PZT transducers. A comparison of the arrival times of the PZT pairs between the intact and the defected CFFT was made to assess the severity of the voids or the debonding. The feasibility of the methodology was analyzed using a finite-difference time-domain-based numerical simulation. Experiments were setup to validate the numerical results, which showed good agreement with the numerical findings. The results showed that the ultrasonic time-of-flight method is able to detect the concrete infill condition of CFFTs. PMID:27941617

Deformation behavior of FRP-metal composites locally reinforced with carbon fibers

NASA Astrophysics Data System (ADS)

Scholze, M.; Kolonko, A.; Lindner, T.; Lampke, T.; Helbig, F.

2016-03-01

This study investigates variations of hybrid laminates, consisting of one aluminum sheet and a unidirectional glass fiber (GF) reinforced polyamide 6 (PA6) basic structure with partial carbon fiber (CF) reinforcement. To create these heterogeneous FRP laminates, it is necessary to design and produce semi-finished textile-based products. Moreover, a warp knitting machine in conjunction with a warp thread offset unit was used to generate bionic inspired compounds. By the variation of stacking prior to the consolidation process of the hybrid laminate, an oriented CF reinforcement at the top and middle layer of the FRP is realized. In both cases the GFRP layer prevents contact between the aluminum and carbon fibers. In so doing, the high strength of carbon fibers can be transferred to the hybrid laminate in load directions with an active prevention of contact corrosion. The interface strength between thermoplastic and metal component was improved by a thermal spray coating on the aluminum sheet. Because of the high surface roughness and porosity, mechanical interlock was used to provide high interface strength without bonding agents between both components. The resulting mechanical properties of the hybrid laminates are evaluated by three point bending tests in different load directions. The effect of local fiber orientation and layer positioning on failure and deformation mechanism is additionally investigated by digital image correlation (DIC).

Fabry-Perot sensors for the monitoring of FRP reinforced bridge decks

NASA Astrophysics Data System (ADS)

Benmokrane, Brahim; Quirion, Marco; El-Salakawy, Ehab; Debaiky, Ahmed S.; Lackey, Tom

2004-07-01

The extensive use of deicing salts in Canada during winter times is identified as the main reason behind the deterioration of highway bridges and parking garages. To fight this infrastructure crisis, Fibre Reinforced Polymers (FRP) has become a very attractive alternative to traditional reinforcing steel due to their non-corrosive nature and light weight. The replacement of steel with Glass FRP bars in bridge deck slabs has been extensively researched in the last few years. This paper presents the first efforts to implement these bars in two highway bridges in Quebec, Canada, and Vermont, USA. These projects are aimed to prove the feasibility of using GFRP bars in bridge construction. GFRP bars were used as reinforcement for parts of the deck slabs in the two bridges while traditional steel was used in the remaining parts. Fibre Optic Sensors (FOS) were used to measure strains in the concrete, reinforcing bars and steel girders. The sensors were surface mounted on the bars or steel girders using standard glue, or embedded in concrete. Static and dynamic testing of the bridges was done using loaded trucks placed for maximum stresses. The design, construction, testing, and results obtained from the bridges are briefly outlined in this paper. The results indicated the accuracy of the sensors and their feasibility for bridge construction and remote monitoring.

The VBB SEIS experiment of InSight

NASA Astrophysics Data System (ADS)

De Raucourt, Sebastien; Gabsi, Taoufik; Tanguy, Nebut; Mimoun, David; Lognonne, Philippe; Gagnepain-Beyneix, Jeannine; Banerdt, William; Tillier, Sylvain; Hurst, Kenneth

2012-07-01

SEIS is the core payload of InSight, one of the three missions selected for competitive phase A in the frame of the 2010 Discovery AO. It aims at providing unique observation of the interior structure of Mars and to monitor seismic activity of Mars. SEIS will provide the first seismic model from another planet than Earth. SEIS is an hybrid seismometer composed of 3 SPs and 3 VBBs axes providing ground motion measurement from Dc to 50Hz. A leveling system will ensure the coupling between the ground and the sensors as well as the horizontality of the VBB sphere. This assembly will be deployed on the ground of Mars and will be shielded by a strong thermal insulation and a wind shield. The 24 bits low noise acquisition electronics will remain in the warm electronic box of the lander with the sensors feedback and leveling system electronics. The VBB sphere enclosed three single axis sensors. Those sensors are based on an inverted leaf spring pendulum, which convert ground acceleration into mobile mass displacement. A capacitive displacement sensor monitors this mass displacement to provide a measurement. A force feedback allows transfer function and sensitivity tuning. The VBB sensor has a very strong heritage from previous project and benefits from recent work to improve its performances. Both the mechanical design and the displacement sensors have optimized to improve performances while reducing technological risk and keeping a high TRL. From those development a self-noise well below 10 ^{-9} m.s ^{-2}/sqrt Hz is expected. Environmental sensitivity of SEIS has been minimized by the design of a very efficient wind and thermal shield. Remaining noise is expected to be very close to the VBB self-noise. Associated sources and budget will be discussed. If InSight is selected to fly in 2016, this experiment will provide very high quality seismic signal measurement with a wider bandwidth, higher sensitivity and lower noise than previous Mars seismometer (Viking and Optimism

Modeling of high-strength concrete-filled FRP tube columns under cyclic load

NASA Astrophysics Data System (ADS)

Ong, Kee-Yen; Ma, Chau-Khun; Apandi, Nazirah Mohd; Awang, Abdullah Zawawi; Omar, Wahid

2018-05-01

The behavior of high-strength concrete (HSC) - filled fiber-reinforced-polymer (FRP) tubes (HSCFFTs) column subjected to cyclic lateral loading is presented in this paper. As the experimental study is costly and time consuming, a finite element analysis (FEA) is chosen for the study. Most of the previous studies have focused on examining the axial load behavior of HSCFFT column instead of seismic behavior. The seismic behavior of HSCFFT columns has been the main interest in the industry. The key objective of this research is to develop a reliable numerical non-linear FEA model to represent the seismic behavior of such column. A FEA model was developed using the Concrete Damaged Plasticity Model (CDPM) available in the finite element software package (ABAQUS). Comparisons between experimental results from previous research and the predicted results were made based on load versus displacement relationships and ultimate strength of the column. The results showed that the column increased in ductility and able to deform to a greater extent with the increase of the FRP confinement ratio. With the increase of confinement ratio, HSCFFT column achieved a higher moment resistance, thus indicated a higher failure strength in the column under cyclic lateral load. It was found that the proposed FEA model can regenerate the experimental results with adequate accuracy.

Experimental evaluation and design of unfilled and concrete-filled FRP composite piles : Task 4A : design specifications.

DOT National Transportation Integrated Search

2015-08-01

The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP composite piles for load-bearing in bridges. This report covers Task 4A, Design Specifications. : Structural design specifications are base...

Strain Gage Loads Calibration Testing with Airbag Support for the Gulfstream III SubsoniC Research Aircraft Testbed (SCRAT)

NASA Technical Reports Server (NTRS)

Lokos, William A.; Miller, Eric J.; Hudson, Larry D.; Holguin, Andrew C.; Neufeld, David C.; Haraguchi, Ronnie

2015-01-01

This paper describes the design and conduct of the strain-gage load calibration ground test of the SubsoniC Research Aircraft Testbed, Gulfstream III aircraft, and the subsequent data analysis and results. The goal of this effort was to create and validate multi-gage load equations for shear force, bending moment, and torque for two wing measurement stations. For some of the testing the aircraft was supported by three airbags in order to isolate the wing structure from extraneous load inputs through the main landing gear. Thirty-two strain gage bridges were installed on the left wing. Hydraulic loads were applied to the wing lower surface through a total of 16 load zones. Some dead-weight load cases were applied to the upper wing surface using shot bags. Maximum applied loads reached 54,000 lb. Twenty-six load cases were applied with the aircraft resting on its landing gear, and 16 load cases were performed with the aircraft supported by the nose gear and three airbags around the center of gravity. Maximum wing tip deflection reached 17 inches. An assortment of 2, 3, 4, and 5 strain-gage load equations were derived and evaluated against independent check cases. The better load equations had root mean square errors less than 1 percent. Test techniques and lessons learned are discussed.

Value engineering and cost effectiveness of various fiber reinforced polymer (FRP) repair systems : final report, June 2007.

DOT National Transportation Integrated Search

2007-06-01

This report is an extension to the final report for NCDOT project 2004-15 Value Engineering and Cost-Effectiveness of : Various Fiber Reinforced Polymers (FRP) Repair Systems, submitted in June 2005. In that report, seventeen 30-ft long : prest...

Strengthening of rural bridges using rapid-installation FRP technology : route 63 bridge no. H356, Phelps County.

DOT National Transportation Integrated Search

2009-10-01

This report presents the use of externally bonded fiber reinforced polymers (FRP) laminates for the flexural strengthening of a : concrete bridge. The bridge selected for this project is a two-span simply supported reinforced concrete slab with no tr...

BlueSeis3A - performance, laboratory tests and applications

NASA Astrophysics Data System (ADS)

Bernauer, F.; Wassermann, J. M.; de Toldi, E.; Guattari, F.; Ponceau, D.; Ripepe, M.; Igel, H.

2017-12-01

One of the most emerging developments in seismic instrumentation is the application of fiber optic gyroscopes as portable rotational ground motion sensors. In the framework of the European Research Council Project, ROMY (ROtational Motions in seismologY), BlueSeis3A was developed in a collaboration between researchers from Ludwig-Maximilians University of Munich, Germany, and the fiber optic sensors manufacturer iXblue, France. With its high sensitivity (20 nrads-1Hz-1/2) in a broad frequency range (0.001 Hz to 50 Hz) BlueSeis3A opens a variety of applications which were up to now hampered by the lack of such an instrument. In this contribution, we will first present performance characteristics of BlueSeis3A with a focus on timing stability and scale factor linearity. In a second part we demonstrate the benefit of directly measured rotational motion for dynamic tilt correction of measurements made with a classical seismometer. A well known tilt signal was produced with a shake table and recorded simultaneously with a classical seismometer and BlueSeis3A. The seismometer measurement could be improved significantly by subtracting the coherent tilt signal which was measured directly with the rotational motion sensor. As a last part we show the advantage of directly measured rotational motion for applications in civil engineering. Results from a measurement campaign in the Giotto bell tower in the city of Florence, Italy, show the possibility of direct observation of torsional modes by deploying a rotational motion sensor inside the structure.

Numerical Analysis of a Masonry Panel Reinforced with Pultruded FRP Frames

NASA Astrophysics Data System (ADS)

Casalegno, C.; Russo, S.; Sciarretta, F.

2018-05-01

The paper presents a numerical study on the retrofit of traditional masonry with pultruded GFRP profile frames adjacent to a wall and connected to it by mechanical fasteners. This kind of retrofit solution, not having been explored yet either in theory or practice, is similar to the common steel frame retrofits, but offers the advantages of lightness and durability of FRP composite materials. The retrofit system proposed, once proven effective and advantageous, would bring a considerable potential innovation into its available options. Three different frame geometries and two cases of masonry thickness were considered to investigate the effectiveness of the retrofit GFRP frame on the inplane static response of the wall to horizontal loads. The global and local (connection) failure behavior of the wall-frame system was investigated using the 3D finite-element method. A general increase in strength after the retrofit, up to about 130%, was found, and a switch from rocking to the diagonal tension failure mode was observed. The strength hierarchy of the retrofitted systems was also analyzed to clarify the effectiveness of the retrofit in imparting a residual strength to masonry. A thinner masonry structure was clearly recognized to have got the greatest benefits, but the retrofit could also significantly improve the inplane shear strength of a thicker wall. A comparison with steel structures of analogous capacity in terms of weight and natural vibration frequencies supported the viability of composite FRP frames for retrofit.

Tricuspid valve chordal rupture due to airbag injury and review of pathophysiological mechanisms.

PubMed

Thekkudan, Joyce; Luckraz, Heyman; Ng, Alex; Norell, Mike

2012-09-01

Blunt trauma to the chest is associated with significant morbidity and mortality. The latter is usually due to an aortic transection, whereas the former is related to myocardial contusion, cardiac valve injury, coronary artery disruption and intracardiac shunts due to the formation of septal defects. The main mechanisms causing these injuries are due to the sudden deceleration force and compression within the chest cavity. Moreover, there is also the sudden increase in intravascular pressure due to a mechanical compression effect and a hormonal adrenergic surge during the event. We report a case of a tricuspid valve injury caused by the deployment of the airbag during a high-speed impact car accident and the subsequent damage to the tricuspid valve chordal mechanism. The patient's management and the pathophysiological mechanisms involved in the injury are reviewed.

Experimental Research of FRP Composite Tube Confined Steel-reinforced Concrete Stub Columns Under Axial Compression

NASA Astrophysics Data System (ADS)

Wang, Ji Zhong; Cheng, Lu; Wang, Xin Pei

2018-06-01

A new column of FRP composite tube confined steel-reinforced concrete (FTCSRC) column was proposed. This paper elaborates on laboratorial and analytical studies on the behavior of FCTSRC columns subjected to axial compressive load. Eight circular FTCSRC stub columns and one circular steel tube confined concrete (STCC) stub column were tested to investigate the failure mode and axial compression performance of circular FTCRSC columns. Parametric analysis was implemented to inquire the influence of confinement material (CFRP-steel tube or CFRP-GFRP tube), internal steel and CFRP layers on the ultimate load capacity. CFRP-steel composite tube was composed of steel tube and CFRP layer which was wrapped outside the steel tube, while CFRP-GFRP composite tube was composite of GFRP tube and CFRP layer. The test results indicate that the confinement effect of CFRP-steel tube is greatly superior to CFRP-GFRP tube. The ductility performance of steel tube confined high-strength concrete column can be improved obviously by encasing steel in the core concrete. Furthermore, with the increase in the layers of FRP wraps, the axial load capacity increases greatly.

Experimental evaluation and design of unfilled and concrete-filled FRP composite piles : Task 7 : final report : thesis.

DOT National Transportation Integrated Search

2015-05-01

The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP composite piles for load-bearing in bridges. This report covers Task 7, Final Report - Thesis. : This final report covers Tasks 1, 2, 3, 5 ...

Simulation of air-bag impact on an eye with transsclerally fixated posterior chamber intraocular lens using finite element analysis.

PubMed

Uchio, Eiichi; Kadonosono, Kazuaki; Matsuoka, Yasuhiro; Goto, Satoru

2004-02-01

To determine the physical and mechanical conditions of an impacting air bag that would rupture an eye with a transsclerally fixated posterior chamber intraocular lens (IOL). Numerical simulation study on a computer. Simulations in a model human eye were performed with a computer using the finite element analysis program PAM-CRASH (Nihon ESI). The air bag was set to impact the surface of an eye with a transsclerally fixated posterior chamber IOL at various velocities. The tensile force limit of a 10-1 polypropylene suture was assumed to be 0.16 N, which is specified in the U.S. Pharmacopeia XXII. At the lowest velocity of 20.0 m/s, 10-0 polypropylene sutures were not likely to break. Sutures fixating the IOL might break and a corneoscleral incision was likely to open after 0.3 second at the medium impacting velocity (30 m/s). Suture rupture was very likely at the highest velocity (40 m/s) since the tensile force on the sutures continuously exceeded the breaking force after the impact. In an eye with a transsclerally fixated posterior chamber IOL, severe ocular trauma can be caused by an air bag at high velocity. Small individuals such as elderly women are at greater risk for air-bag ocular injury. Further research on modifying air-bag design and deployment is important to minimize the risk for ocular injury.

SeisCode: A seismological software repository for discovery and collaboration

NASA Astrophysics Data System (ADS)

Trabant, C.; Reyes, C. G.; Clark, A.; Karstens, R.

2012-12-01

SeisCode is a community repository for software used in seismological and related fields. The repository is intended to increase discoverability of such software and to provide a long-term home for software projects. Other places exist where seismological software may be found, but none meet the requirements necessary for an always current, easy to search, well documented, and citable resource for projects. Organizations such as IRIS, ORFEUS, and the USGS have websites with lists of available or contributed seismological software. Since the authors themselves do often not maintain these lists, the documentation often consists of a sentence or paragraph, and the available software may be outdated. Repositories such as GoogleCode and SourceForge, which are directly maintained by the authors, provide version control and issue tracking but do not provide a unified way of locating geophysical software scattered in and among countless unrelated projects. Additionally, projects are hosted at language-specific sites such as Mathworks and PyPI, in FTP directories, and in websites strewn across the Web. Search engines are only partially effective discovery tools, as the desired software is often hidden deep within the results. SeisCode provides software authors a place to present their software, codes, scripts, tutorials, and examples to the seismological community. Authors can choose their own level of involvement. At one end of the spectrum, the author might simply create a web page that points to an existing site. At the other extreme, an author may choose to leverage the many tools provided by SeisCode, such as a source code management tool with integrated issue tracking, forums, news feeds, downloads, wikis, and more. For software development projects with multiple authors, SeisCode can also be used as a central site for collaboration. SeisCode provides the community with an easy way to discover software, while providing authors a way to build a community around their

Draft SEI Program Plans: 1994-1998

DTIC Science & Technology

1993-08-01

process must depersonalize risks so they are viewed as opportunities for program success. Factors for communication are in all the method devel...and the undergraduate level to adequately prepare new soft- ware engineers entering the work force. Educators and trainers of current professionals...learning opportu- nities. The technical foundation for many of these products is the evolving SEI model curricula for graduate and undergraduate degree

Monitoring Poisson's Ratio Degradation of FRP Composites under Fatigue Loading Using Biaxially Embedded FBG Sensors.

PubMed

Akay, Erdem; Yilmaz, Cagatay; Kocaman, Esat S; Turkmen, Halit S; Yildiz, Mehmet

2016-09-19

The significance of strain measurement is obvious for the analysis of Fiber-Reinforced Polymer (FRP) composites. Conventional strain measurement methods are sufficient for static testing in general. Nevertheless, if the requirements exceed the capabilities of these conventional methods, more sophisticated techniques are necessary to obtain strain data. Fiber Bragg Grating (FBG) sensors have many advantages for strain measurement over conventional ones. Thus, the present paper suggests a novel method for biaxial strain measurement using embedded FBG sensors during the fatigue testing of FRP composites. Poisson's ratio and its reduction were monitored for each cyclic loading by using embedded FBG sensors for a given specimen and correlated with the fatigue stages determined based on the variations of the applied fatigue loading and temperature due to the autogenous heating to predict an oncoming failure of the continuous fiber-reinforced epoxy matrix composite specimens under fatigue loading. The results show that FBG sensor technology has a remarkable potential for monitoring the evolution of Poisson's ratio on a cycle-by-cycle basis, which can reliably be used towards tracking the fatigue stages of composite for structural health monitoring purposes.

Required number of records for ASCE/SEI 7 ground-motion scaling procedure

USGS Publications Warehouse

Reyes, Juan C.; Kalkan, Erol

2011-01-01

The procedures and criteria in 2006 IBC (International Council of Building Officials, 2006) and 2007 CBC (International Council of Building Officials, 2007) for the selection and scaling ground-motions for use in nonlinear response history analysis (RHA) of structures are based on ASCE/SEI 7 provisions (ASCE, 2005, 2010). According to ASCE/SEI 7, earthquake records should be selected from events of magnitudes, fault distance, and source mechanisms that comply with the maximum considered earthquake, and then scaled so that the average value of the 5-percent-damped response spectra for the set of scaled records is not less than the design response spectrum over the period range from 0.2Tn to 1.5Tn sec (where Tn is the fundamental vibration period of the structure). If at least seven ground-motions are analyzed, the design values of engineering demand parameters (EDPs) are taken as the average of the EDPs determined from the analyses. If fewer than seven ground-motions are analyzed, the design values of EDPs are taken as the maximum values of the EDPs. ASCE/SEI 7 requires a minimum of three ground-motions. These limits on the number of records in the ASCE/SEI 7 procedure are based on engineering experience, rather than on a comprehensive evaluation. This study statistically examines the required number of records for the ASCE/SEI 7 procedure, such that the scaled records provide accurate, efficient, and consistent estimates of" true" structural responses. Based on elastic-perfectly-plastic and bilinear single-degree-of-freedom systems, the ASCE/SEI 7 scaling procedure is applied to 480 sets of ground-motions. The number of records in these sets varies from three to ten. The records in each set were selected either (i) randomly, (ii) considering their spectral shapes, or (iii) considering their spectral shapes and design spectral-acceleration value, A(Tn). As compared to benchmark (that is, "true") responses from unscaled records using a larger catalog of ground

Cluster-search based monitoring of local earthquakes in SeisComP3

NASA Astrophysics Data System (ADS)

Roessler, D.; Becker, J.; Ellguth, E.; Herrnkind, S.; Weber, B.; Henneberger, R.; Blanck, H.

2016-12-01

We present a new cluster-search based SeisComP3 module for locating local and regional earthquakes in real time. Real-time earthquake monitoring systems such as SeisComP3 provide the backbones for earthquake early warning (EEW), tsunami early warning (TEW) and the rapid assessment of natural and induced seismicity. For any earthquake monitoring system fast and accurate event locations are fundamental determining the reliability and the impact of further analysis. SeisComP3 in the OpenSource version includes a two-stage detector for picking P waves and a phase associator for locating earthquakes based on P-wave detections. scanloc is a more advanced earthquake location program developed by gempa GmbH with seamless integration into SeisComP3. scanloc performs advanced cluster search to discriminate earthquakes occurring closely in space and time and makes additional use of S-wave detections. It has proven to provide fast and accurate earthquake locations at local and regional distances where it outperforms the base SeisComP3 tools. We demonstrate the performance of scanloc for monitoring induced seismicity as well as local and regional earthquakes in different tectonic regimes including subduction, spreading and intra-plate regions. In particular we present examples and catalogs from real-time monitoring of earthquake in Northern Chile based on data from the IPOC network by GFZ German Research Centre for Geosciences for the recent years. Depending on epicentral distance and data transmission, earthquake locations are available within a few seconds after origin time when using scanloc. The association of automatic S-wave detections provides a better constraint on focal depth.

Strengthening of reinforced concrete beams with basalt-based FRP sheets: An analytical assessment

NASA Astrophysics Data System (ADS)

Nerilli, Francesca; Vairo, Giuseppe

2016-06-01

In this paper the effectiveness of the flexural strengthening of RC beams through basalt fiber-reinforced sheets is investigated. The non-linear flexural response of RC beams strengthened with FRP composites applied at the traction side is described via an analytical formulation. Validation results and some comparative analyses confirm soundness and consistency of the proposed approach, and highlight the good mechanical performances (in terms of strength and ductility enhancement of the beam) produced by basalt-based reinforcements in comparison with traditional glass or carbon FRPs.

Strengthening of reinforced concrete beams with basalt-based FRP sheets: An analytical assessment

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

Nerilli, Francesca; Vairo, Giuseppe

2016-06-08

In this paper the effectiveness of the flexural strengthening of RC beams through basalt fiber-reinforced sheets is investigated. The non-linear flexural response of RC beams strengthened with FRP composites applied at the traction side is described via an analytical formulation. Validation results and some comparative analyses confirm soundness and consistency of the proposed approach, and highlight the good mechanical performances (in terms of strength and ductility enhancement of the beam) produced by basalt-based reinforcements in comparison with traditional glass or carbon FRPs.

How many records should be used in ASCE/SEI-7 ground motion scaling procedure?

USGS Publications Warehouse

Reyes, Juan C.; Kalkan, Erol

2012-01-01

U.S. national building codes refer to the ASCE/SEI-7 provisions for selecting and scaling ground motions for use in nonlinear response history analysis of structures. Because the limiting values for the number of records in the ASCE/SEI-7 are based on engineering experience, this study examines the required number of records statistically, such that the scaled records provide accurate, efficient, and consistent estimates of “true” structural responses. Based on elastic–perfectly plastic and bilinear single-degree-of-freedom systems, the ASCE/SEI-7 scaling procedure is applied to 480 sets of ground motions; the number of records in these sets varies from three to ten. As compared to benchmark responses, it is demonstrated that the ASCE/SEI-7 scaling procedure is conservative if fewer than seven ground motions are employed. Utilizing seven or more randomly selected records provides more accurate estimate of the responses. Selecting records based on their spectral shape and design spectral acceleration increases the accuracy and efficiency of the procedure.

Experimental evaluation and design of unfilled and concrete-filled FRP composite piles : Task 4B : material & construction specifications : final report.

DOT National Transportation Integrated Search

2015-07-01

The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP composite piles for load-bearing in bridges. This report covers Task 4B, Materials and Construction Specifications. : This technical report...

Shizuko Sei, MD | Division of Cancer Prevention

Cancer.gov

Dr. Shizuko Sei (formerly Shizuko Aoki) is a medical officer with over 27 years of translational and clinical research experience in the field of cancer and AIDS. After completing her pediatric oncology fellowship at NCI Center for Cancer Research (CCR), she held various positions in the CCR and Division of Cancer Treatment and Diagnosis (DCTD) before joining the DCP in July

The GEMS-2 SEIS Experiment

NASA Astrophysics Data System (ADS)

Tillier, S.; De Raucourt, S.; Mimoun, D.; Lognonne, P.; Giardini, D.; Christensen, U. R.; Pike, W. T.; Banerdt, B.; Laudet, P.; Kerjean, L.; Hurst, K. J.; Zweifel, P.; Mance, D.; Roll, R.; Bierwirth, M.; Gagnepain-Beyneix, J.; Nibut, T.; Robert, O.; Gabsi, T.; Pot, O.; Lecomte, B.; Schibler, P.; Mocquet, A.; Garcia, R.

2011-12-01

The SEIS experiment is the primary payload of the Geophysical Monitoring Station (GEMS) Mission Proposal, submitted to NASA in the frame of the 2010 Discovery program, and recently selected for the phase A study. The objective of the GEMS SEIS experiment is the determination of the deep internal structure of Mars. In particular, geophysical parameters of first importance, such as the state (liquid/solid) and size of the core, as well as structure of the mantle and shape of discontinuities will be determined by the experiment. It will measure seismic activity in a very broad band of signal, from the tidal frequencies (0.05 mHz) up to the short period frequencies (50 Hz), to address the widest range of scientific questions, from the state of the inner core to the meteoritic rate measurement. Infrasound, which might be associated to dust devils and atmospheric discharge, will be also monitored. The instrument integrates a Very Broad Band (VBB) 3 axis seismometer, completed by another trihedron of MEMS short period seismometers, environmental sensors for pressure, wind and temperature, and an infrasound sensor is additionally considered. The sensors will be deployed on the Martian ground by a robotic arm from the Phoenix lander platform and protected by a wind and thermal shield. The sensor assembly, which contains all seismic sensors, the leveling system, as well as house-keeping and temperature measurements, will be deployed on the soil in order to allow the best possible mechanical coupling with the ground motion. Thanks to the wind and thermal shield, together with the sensors' specific containers (vacuum sphere for VBBs), long term VBB bias will be protected from both temperature and pressure variations (as well as passively compensated), allowing the sensor to operate in the rough Martian thermal environment. A dedicated electronics will manage the overall experiment and ultra-low noise, space qualified 24 bits A/D converters will perform the acquisition. The

Monitoring Poisson’s Ratio Degradation of FRP Composites under Fatigue Loading Using Biaxially Embedded FBG Sensors

PubMed Central

Akay, Erdem; Yilmaz, Cagatay; Kocaman, Esat S.; Turkmen, Halit S.; Yildiz, Mehmet

2016-01-01

The significance of strain measurement is obvious for the analysis of Fiber-Reinforced Polymer (FRP) composites. Conventional strain measurement methods are sufficient for static testing in general. Nevertheless, if the requirements exceed the capabilities of these conventional methods, more sophisticated techniques are necessary to obtain strain data. Fiber Bragg Grating (FBG) sensors have many advantages for strain measurement over conventional ones. Thus, the present paper suggests a novel method for biaxial strain measurement using embedded FBG sensors during the fatigue testing of FRP composites. Poisson’s ratio and its reduction were monitored for each cyclic loading by using embedded FBG sensors for a given specimen and correlated with the fatigue stages determined based on the variations of the applied fatigue loading and temperature due to the autogenous heating to predict an oncoming failure of the continuous fiber-reinforced epoxy matrix composite specimens under fatigue loading. The results show that FBG sensor technology has a remarkable potential for monitoring the evolution of Poisson’s ratio on a cycle-by-cycle basis, which can reliably be used towards tracking the fatigue stages of composite for structural health monitoring purposes. PMID:28773901

Anchorage strength models for end-debonding predictions in RC beams strengthened with FRP composites

NASA Astrophysics Data System (ADS)

Nardini, V.; Guadagnini, M.; Valluzzi, M. R.

2008-05-01

The increase in the flexural capacity of RC beams obtained by externally bonding FRP composites to their tension side is often limited by the premature and brittle debonding of the external reinforcement. An in-depth understanding of this complex failure mechanism, however, has not yet been achieved. With specific regard to end-debonding failure modes, extensive experimental observations reported in the literature highlight the important distinction, often neglected in strength models proposed by researchers, between the peel-off and rip-off end-debonding types of failure. The peel-off failure is generally characterized by a failure plane located within the first few millimetres of the concrete cover, whilst the rip-off failure penetrates deeper into the concrete cover and propagates along the tensile steel reinforcement. A new rip-off strength model is described in this paper. The model proposed is based on the Chen and Teng peel-off model and relies upon additional theoretical considerations. The influence of the amount of the internal tensile steel reinforcement and the effective anchorage length of FRP are considered and discussed. The validity of the new model is analyzed further through comparisons with test results, findings of a numerical investigation, and a parametric study. The new rip-off strength model is assessed against a database comprising results from 62 beams tested by various researchers and is shown to yield less conservative results.

Effect of Vinylene Carbonate and Fluoroethylene Carbonate on SEI Formation on Graphitic Anodes in Li-Ion Batteries

DOE PAGES

Nie, Mengyun; Demeaux, Julien; Young, Benjamin T.; ...

2015-07-23

Binder free (BF) graphite electrodes were utilized to investigate the effect of electrolyte additives fluoroethylene carbonate (FEC) and vinylene carbonate (VC) on the structure of the solid electrolyte interface (SEI). The structure of the SEI has been investigated via ex-situ surface analysis including X-ray Photoelectron spectroscopy (XPS), Hard XPS (HAXPES), Infrared spectroscopy (IR) and transmission electron microscopy (TEM). The components of the SEI have been further investigated via nuclear magnetic resonance (NMR) spectroscopy of D2O extractions. The SEI generated on the BF-graphite anode with a standard electrolyte (1.2 M LiPF6 in ethylene carbonate (EC) / ethyl methyl carbonate (EMC), 3/7more » (v/v)) is composed primarily of lithium alkyl carbonates (LAC) and LiF. Incorporation of VC (3% wt) results in the generation of a thinner SEI composed of Li2CO3, poly(VC), LAC, and LiF. Incorporation of VC inhibits the generation of LAC and LiF. Incorporation of FEC (3% wt) also results in the generation of a thinner SEI composed of Li2CO3, poly(FEC), LAC, and LiF. The concentration of poly(FEC) is lower than the concentration of poly(VC) and the generation of LAC is inhibited in the presence of FEC. The SEI appears to be a homogeneous film for all electrolytes investigated.« less

[Effect of Biejiajian Pills on Wnt/β-catenin signal pathway and DKK-1 and FrpHe gene expressions in hepatocellular carcinoma cells].

PubMed

He, Songqi; Cheng, Yang; Zhu, Yun; Fan, Qin; Sun, Haitao; Jia, Wenyan

2013-01-01

To investigate the effect of Biejiajian Pills on Wnt signal pathway and its inhibitory gene (DKK-1 and FrpHe) expressions and explore the mechanism underlying the action of Biejiajian Pills to suppress the invasiveness of hepatocellular carcinoma. Twenty-four Wistar rats were randomized equally into 3 groups for gavage of normal saline and Biejiajian Pills at 20- and 10-fold clinical doses for 3 days. Blood samples were then collected from the rats, and the serum was separated and added in HepG2 cell cultures. After 48 h of culture, the cells were collected to determine the cellular content of β-catenin protein using flow cytometry and detect DKK-1 and FrpHe mRNA expressions using qRT-PCR. HepG2 cells cultured in the presence of sera from rats fed with Biejiajian Pills showed significantly lowered β-catenin protein expression and obvious down-regulation of DKK-1 mRNA expression, and the effect was correlated with the doses of the drug administered. The expression of FrpHe mRNA showed no significant differences between the 3 groups. Biejiajian Pills can effectively inhibit the invasiveness and migration of hepatocellular carcinoma cells, which is closely related to decreased expressions of β-catenin and DKK-1 to cause block of the Wnt/β-catenin signal pathway.

[Chang Sei Kim's activities on public health in colonial Korea].

PubMed

Park, Yunjae

2006-12-01

After graduating from Severance Medical College in 1916, Chang Sei Kim went to Shanghai to work as a missionary in a adventist hospital. The establishment of the Korean Provisional Government led him to participate in the independence movement. Educating nurses to assist the forthcoming war for independence, he seemed to realize the fact that the health of Koreans would be a key factor for achieving independence. He left for the U.S. to conduct comprehensive research on medicine. Chang Sei Kim was the first Korean to receive a Ph. D. degree of Public Health, graduating from the Johns Hopkins School of Hygiene and Public Health in 1925. He then gained an opportunity to work for Korea as a professor at Severance Medical College. His objective was the 'Reconstruction of the Korean People In Terms of Physical Constitution.' He pointed out that Koreans' weak state of health was a major reason for Korea's colonization. To gain independence, he emphasized that the Korean people should receive education on public health in order to improve the primitive conditions of sanitation. There is little doubt that Chang Sei Kim's ideas developed Heungsadan's views on medicine in terms of its stress on cultivation of ability, especially considering the fact that he was a member of the organization. As a member of the colonized who could not participate in the developing official policy, Chang Sei Kim was not able to implement his ideas fully, because an individual or a private organization could not carry out policy on public health as large a scale as the government did. Never giving up his hopes for Korean independence, he rejected requests to assume official posts in the Government-General. That was why he was particularly interested in the Self-Governing Movement in 1920s Korea. If the movement had attained its goal, he might have worked for the enhancement of sanitary environment as a director of Sanitary Department. His application for funding to establish a hygiene laboratory

Homogenized rigid body and spring-mass (HRBSM) model for the pushover analysis of out-of-plane loaded unreinforced and FRP reinforced walls

NASA Astrophysics Data System (ADS)

Bertolesi, Elisa; Milani, Gabriele

2017-07-01

The present paper is devoted to the discussion of a series of unreinforced and FRP retrofitted panels analyzed adopting the Rigid Body and Spring-Mass (HRBSM) model developed by the authors. To this scope, a total of four out of plane loaded masonry walls tested up to failure are considered. At a structural level, the non-linear analyses are conducted replacing the homogenized orthotropic continuum with a rigid element and non-linear spring assemblage by means of which out of plane mechanisms are allowed. FRP retrofitting is modeled adopting two noded truss elements whose mechanical properties are selected in order to describe possible debonding phenomenon or tensile rupture of the strengthening. The outcome provided numerically are compared to the experimental results showing a satisfactory agreement in terms of global pressure-deflection curves and failure mechanisms.

Behaviour of square FRP-Confined High-Strength Concrete Columns under Eccentric Compression

NASA Astrophysics Data System (ADS)

Fallah Pour, Ali; Gholampour, Aliakbar; Zheng, Junai; Ozbakkaloglu, Togay

2018-01-01

This paper presents the results of an experimental study on the effect of load eccentricity on the axial compressive behaviour of carbon fibre-reinforced polymer (CFRP)- confined high-strength concrete (HSC) columns with a square cross-section. The axial loading was applied to the specimens at six different load eccentricities ranging from zero to 50 mm. The results show that the load eccentricity significantly influences the axial load-displacement and axial stress-strain behaviour of FRP-confined HSC. Increasing the load eccentricity leads to an increase in the ultimate axial strain but a decrease in the ultimate axial stress and second branch slope of the axial stress-strain curve.

46 CFR 160.035-8 - Construction of fibrous glass reinforced plastic (F.R.P.), oar-, hand-, and motor-propelled...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 6 2011-10-01 2011-10-01 false Construction of fibrous glass reinforced plastic (F.R.P... APPROVAL LIFESAVING EQUIPMENT Lifeboats for Merchant Vessels § 160.035-8 Construction of fibrous glass... set forth in this subpart. (2) Fibrous glass reinforced plastic lifeboats may be of the following...

46 CFR 160.035-8 - Construction of fibrous glass reinforced plastic (F.R.P.), oar-, hand-, and motor-propelled...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 6 2010-10-01 2010-10-01 false Construction of fibrous glass reinforced plastic (F.R.P... APPROVAL LIFESAVING EQUIPMENT Lifeboats for Merchant Vessels § 160.035-8 Construction of fibrous glass... set forth in this subpart. (2) Fibrous glass reinforced plastic lifeboats may be of the following...

SIAH1-induced p34SEI-1 polyubiquitination/degradation mediates p53 preferential vitamin C cytotoxicity.

PubMed

Lee, Soonduck; Kim, Jinsun; Jung, Samil; Li, Chengping; Yang, Young; Kim, Keun Il; Lim, Jong-Seok; Kim, Yonghwan; Cheon, Choong-Il; Lee, Myeong-Sok

2015-03-01

Vitamin C is considered as an important anticancer therapeutic agent although this view is debatable. In this study, we introduce a physiological mechanism demonstrating how vitamin C exerts anticancer activity that induces cell cycle arrest and apoptosis. Our previous and current data reveal that p53 tumor suppressor is the prerequisite factor for stronger anticancer effects of vitamin C. In addition, vitamin C-mediated cancer cell cytotoxicity appears to be achieved at least partly through the downregulation of the p34SEI-1 oncoprotein. Our previous study showed that p34SEI-1 increases the survival of various types of cancer cells by inhibiting their apoptosis. Present data suggest that vitamin C treatment decreases the p34SEI-1 expression at the protein level and therefore alleviates its anti-apoptotic activity. Of note, SIAH1, E3 ubiquitin ligase, appears to be responsible for the p34SEI-1 polyubiquitination and its subsequent degradation, which is dependent on p53. In summary, vitamin C increases cancer cell death by inducing SIAH1-mediated polyubiquitination/degradation of the p34SEI-1 oncoprotein in a p53-dependent manner.

75 FR 39916 - Endangered and Threatened Species; Notice of Intent to Prepare a Recovery Plan for the Sei Whale

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-13

... Fisheries Service (NMFS) is announcing its intent to prepare a recovery plan for the Sei Whale (Balaenoptera... the fax comments as ``Sei Whale Recovery Plan Information'' 3. Mail: National Marine Fisheries Service... and Threatened Species; Notice of Intent to Prepare a Recovery Plan for the Sei Whale AGENCY: National...

Structural Performance of a Hybrid FRP-Aluminum Modular Triangular Truss System Subjected to Various Loading Conditions

PubMed Central

Zhang, Dongdong; Huang, Yaxin; Zhao, Qilin; Li, Fei; Gao, Yifeng

2014-01-01

A novel hybrid FRP-aluminum truss system has been employed in a two-rut modular bridge superstructure composed of twin inverted triangular trusses. The actual flexural behavior of a one-rut truss has been previously investigated under the on-axis loading test; however, the structural performance of the one-rut truss subjected to an off-axis load is still not fully understood. In this paper, a geometrical linear finite element model is introduced and validated by the on-axis loading test; the structural performance of the one-rut truss subjected to off-axis load was numerically obtained; the dissimilarities of the structural performance between the two different loading cases are investigated in detail. The results indicated that (1) the structural behavior of the off-axis load differs from that of the on-axis load, and the off-axis load is the critical loading condition controlling the structural performance of the triangular truss; (2) under the off-axis load, the FRP trussed members and connectors bear certain out-of-plane bending moments and are subjected to a complicated stress state; and (3) the stress state of these members does not match that of the initial design, and optimization for the redesign of these members is needed, especially for the pretightened teeth connectors. PMID:25254254

Effects of FRP application on the seismic response of a masonry church in Emilia-Romagna (Italy)

NASA Astrophysics Data System (ADS)

Milani, Gabriele; Shehu, Rafael; Valente, Marco

2016-12-01

The paper presents some preliminary results of advanced Finite Element (FE) analyses on the upgrading of old masonry constructions by means of Fiber Reinforced Polymers (FRPs). The case study is a masonry Romanesque church, located in Ferrara, Emilia Romagna (Italy). The church exhibits widespread damage caused by the recent earthquake sequence occurred in 2012 about 60 km far from Ferrara with two major seismic events of magnitude 5.8 and 5.9. The main damage involved mainly the columns of the central nave and the apse. A partial detachment of the façade was observed too. First, gravity load analyses and non-linear static and dynamic analyses are performed on the church in the unretrofitted configuration. Numerical results put in evidence the insufficient strength of the apse and the columns of the naves, and the detachment of the façade. A strengthening intervention conducted by means of FRP strips is numerically analysed, assuming the behavior of the strips, especially for what concerns delamination, in agreement with Italian Guidelines. Numerical results show a quite reasonable strength improvement of the weak structural elements due to FRP application, with levels of strength higher than the minimum ones required by Italian Code.

On the Application of a Response Surface Technique to Analyze Roll-over Stability of Capsules with Airbags Using LS-Dyna

NASA Technical Reports Server (NTRS)

Horta, Lucas G.; Reaves, Mercedes C.

2008-01-01

As NASA moves towards developing technologies needed to implement its new Exploration program, studies conducted for Apollo in the 1960's to understand the rollover stability of capsules landing are being revisited. Although rigid body kinematics analyses of the roll-over behavior of capsules on impact provided critical insight to the Apollo problem, extensive ground test programs were also used. For the new Orion spacecraft being developed to implement today's Exploration program, new air-bag designs have improved sufficiently for NASA to consider their use to mitigate landing loads to ensure crew safety and to enable re-usability of the capsule. Simple kinematics models provide only limited understanding of the behavior of these air bag systems, and more sophisticated tools must be used. In particular, NASA and its contractors are using the LS-Dyna nonlinear simulation code for impact response predictions of the full Orion vehicle with air bags by leveraging the extensive air bag prediction work previously done by the automotive industry. However, even in today's computational environment, these analyses are still high-dimensional, time consuming, and computationally intensive. To alleviate the computational burden, this paper presents an approach that uses deterministic sampling techniques and an adaptive response surface method to not only use existing LS-Dyna solutions but also to interpolate from LS-Dyna solutions to predict the stability boundaries for a capsule on airbags. Results for the stability boundary in terms of impact velocities, capsule attitude, impact plane orientation, and impact surface friction are discussed.

Evaluation of RC Bridge Piers Retrofitted using Fiber-Reinforced Polymer (FRP)

NASA Astrophysics Data System (ADS)

Shayanfar, M. A.; Zarrabian, M. S.

2008-07-01

For many long years, steel reinforcements have been considered as the only tool for concrete confinements and studied widely, but nowadays application of Fiber Reinforced Polymer (FRP) as an effective alternative is well appreciated. Many bridges have been constructed in the past that are necessary to be retrofitted for resisting against the earthquake motions. The objective of this research is evaluation of nonlinear behavior of RC bridge piers. Eight RC bridge piers have been modeled by ABAQUS software under micromechanical model for homogeneous anisotropic fibers. Also the Bilinear Confinement Model by Nonlinear Transition Zone of Mirmiran has been considered. Then types and angles of fibers and their effects on the final responses were evaluated [1]. Finally, effects of retrofitting are evaluated and some suggestions presented.

MatSeis and the GNEM R&E regional seismic anaylsis tools.

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

Chael, Eric Paul; Hart, Darren M.; Young, Christopher John

2003-08-01

To improve the nuclear event monitoring capability of the U.S., the NNSA Ground-based Nuclear Explosion Monitoring Research & Engineering (GNEM R&E) program has been developing a collection of products known as the Knowledge Base (KB). Though much of the focus for the KB has been on the development of calibration data, we have also developed numerous software tools for various purposes. The Matlab-based MatSeis package and the associated suite of regional seismic analysis tools were developed to aid in the testing and evaluation of some Knowledge Base products for which existing applications were either not available or ill-suited. This presentationmore » will provide brief overviews of MatSeis and each of the tools, emphasizing features added in the last year. MatSeis was begun in 1996 and is now a fairly mature product. It is a highly flexible seismic analysis package that provides interfaces to read data from either flatfiles or an Oracle database. All of the standard seismic analysis tasks are supported (e.g. filtering, 3 component rotation, phase picking, event location, magnitude calculation), as well as a variety of array processing algorithms (beaming, FK, coherency analysis, vespagrams). The simplicity of Matlab coding and the tremendous number of available functions make MatSeis/Matlab an ideal environment for developing new monitoring research tools (see the regional seismic analysis tools below). New MatSeis features include: addition of evid information to events in MatSeis, options to screen picks by author, input and output of origerr information, improved performance in reading flatfiles, improved speed in FK calculations, and significant improvements to Measure Tool (filtering, multiple phase display), Free Plot (filtering, phase display and alignment), Mag Tool (maximum likelihood options), and Infra Tool (improved calculation speed, display of an F statistic stream). Work on the regional seismic analysis tools (CodaMag, EventID, PhaseMatch, and

Analytical investigation of a three-dimensional FRP-retrofitted reinforced concrete structure's behaviour under earthquake load effect in ANSYS program

NASA Astrophysics Data System (ADS)

Altun, F.; Birdal, F.

2012-12-01

In this study, a 1:3 scaled, three-storey, FRP (Fiber Reinforced Polymer) retrofitted reinforced concrete model structure whose behaviour and crack development were identified experimentally in the laboratory was investigated analytically. Determination of structural behaviour under earthquake load is only possible in a laboratory environment with a specific scale, as carrying out structural experiments is difficult due to the evaluation of increased parameter numbers and because it requires an expensive laboratory setup. In an analytical study, structure was modelled using ANSYS Finite Element Package Program (2007), and its behaviour and crack development were revealed. When experimental difficulties are taken into consideration, analytical investigation of structure behaviour is more economic and much faster. At the end of the study, experimental results of structural behaviour and crack development were compared with analytical data. It was concluded that in a model structure retrofitted with FRP, the behaviour and cracking model can be determined without testing by determining the reasons for the points where analytical results are not converged with experimental data. Better understanding of structural behaviour is analytically enabled with the study.

Proliferation of Shadow Education Institutions (SEI's) in the Philippines: A Time Series Analysis

ERIC Educational Resources Information Center

de Castro, Belinda V.; de Guzman, Allan B.

2013-01-01

While the issue on the existence of shadow education institutions (SEI's) has only recently been the subject of investigation in studies in various countries worldwide, it is clear that its market is a huge industry in much of Asia and is growing fast elsewhere. Capitalizing on the annual number of SEI's gathered from key government agencies and…

Results of SEI Independent Research and Development Projects

DTIC Science & Technology

2008-07-01

and the processes being followed. The coordination occurs uti- lizing one or more different media types. Figure 2-2: Factors Impacting Coordination...use of one media and be continued using another. Table 2-2: Styles of Coordination and Type of Tool Used for Each Style Teleconference E-mail... social and legal issues, stakeholder management, and training and education. These relationships are shown in Figure 4-1. 19 | CMU/SEI-2008-TR

The state of understanding of the lithium-ion-battery graphite solid electrolyte interphase (SEI) and its relationship to formation cycling

DOE PAGES

An, Seong Jin; Li, Jianlin; Daniel, Claus; ...

2016-04-09

An in-depth review is presented on the science of lithium-ion battery (LIB) solid electrolyte interphase (SEI) formation on the graphite anode, including structure, morphology, chemical composition, electrochemistry, formation mechanism, and LIB formation cycling. During initial operation of LIBs, the SEI layer forms on the graphite surfaces, the most commonly used anode material, due to side reactions with the electrolyte solvent/salt at low electro-reduction potentials. It is accepted that the SEI layer is essential to the long-term performance of LIBs, and it also has an impact on its initial capacity loss, self-discharge characteristics, cycle life, rate capability, and safety. While themore » presence of the anode SEI layer is vital, it is difficult to control its formation and growth, as the chemical composition, morphology, and stability depend on several factors. These factors include the type of graphite, electrolyte composition, electrochemical conditions, and cell temperature. Thus, SEI layer formation and electrochemical stability over long-term operation should be a primary topic of future investigation in the development of LIB technology. We review the progression of knowledge gained about the anode SEI, from its discovery in 1979 to the current state of understanding, and covers its formation process, differences in the chemical and structural makeup when cell materials and components are varied, methods of characterization, and associated reactions with the liquid electrolyte phase. It also discusses the relationship of the SEI layer to the LIB formation step, which involves both electrolyte wetting and subsequent slow charge-discharge cycles to grow the SEI.« less

Simulation of the FRP Product

NASA Astrophysics Data System (ADS)

Paugam, Ronan; Wooster, Martin; Johnston, Joshua; Gastellu-Etchegorry, Jean-Philippe

2014-05-01

Among the different alternative of remote sensing technologies for estimating global fire carbon emission, the thermally-based measures of fire radiative power (FRP; and its temporal integration, fire radiative energy or FRE) has the potential to capture the spatial and temporal variability of fire occurrence. It was shown that a strong linear relationship exists between the total amount of thermal radiant energy emitted by a fire over its lifetime (the FRE) and the amount of fuel burned. Since all vegetation is 50(±5)% carbon, it is therefore in theory a potentially simple matter to measure the FRE and estimate the carbon release. In a fire inventory like the Global Fire Assimilation System (GFAS), the total carbon emission is derived from a gridded FRE product forced by the MODIS observation, using Ct = β x FRE x Ef, where β is a conversion factor initially estimated from small scale experiment as β=0.368 and later derived for different bio dome by comparison with the Global Fire Emission Database (GFED). The sensitivities of the above equation to (i) different types of fire activity (ie, flaming, smoldering, torching), (ii) sensor view angles or (iii) soot/smoke absorption have not yet been well studied. The investigation of these types of sensitivity, and of the information content of thermal IR observations of actively burning fires in general, is one of the primary subjects of this study. Our approach is based on a combination of observational work and simulations conducted via the linkage of different fire models and the 3D radiative transfer (RT) model DART operating in the thermal domain. The radiation properties of a fire as seen from above its plume (e.g. space/air borne sensor) depend on the temperature distribution, the gas concentration (mainly CO2, H2O), and the amount, shape, distribution and optical properties of the soot particles in the flame (where they are emitting) and in the cooling plume (where they are mainly absorbing). While gas and

Finite Element Analysis of Folded Airbag in Frontal Impact of Adapted Vehicles for Disabled Drivers

NASA Astrophysics Data System (ADS)

Masiá, J.; Eixerés, B.; Dols, J. F.; Esquerdo, T. V.

2009-11-01

The car control adaptations are used in vehicles in order to facilitate the driving to persons with physical handicaps. This does not have to suppose a decrease of the passive safety that is required to the vehicles. In order to analyze this relation there will be characterized the different control adaptations that are in use together with the different devices of passive safety that can be mounted in the vehicles in diverse cases of impact in order to generate models of simulation. The methodology used to generate this simulation consists of the first phase in which there develops the three-dimensional model of the driving place. For it, there has been used a commercial software of three-dimensional design. Once realized this one divides, the model is imported to the finite elements software in which meshing is generated. Finally, dynamic simulation software is used to assign the most important characteristics like material properties, contact interfaces, gas expansion models, airbag fold types, etc.

Results of SEI Independent Research and Development Projects

DTIC Science & Technology

2011-02-01

ft’s Bit- poten- hout a ut de- r for CMU/SEI-2011-TR-002 | 8 more systems to install them. The implication to the Department of Defense and...Computing, June 2011. 2.7.1 Bibliography Challener, David; Yoder, K.; Catherman, R .; Saford, D.; & Van Doom, L. A Practical Guide to Trusted...number of publications and presentations: Brown, N.; Nord, R .; & Ozkaya, I. “Enabling Agility Through Architecture.” CrossTalk 23, 6 (November

Experimetal study on the FRP-concrete bond behavior under repeated loadings

NASA Astrophysics Data System (ADS)

Lee, J.-Y.; Yi, C.-K.; Cheong, Y.-G.

2009-11-01

In this study, the effects of repeated loads on the FRP-concrete bond strength were investigated experimentally by direct pull out tests according to CSA S806-02. A conventional reinforcing steel bar and two types of glass-fiber-reinforced plastic (GFRP) bars were embedded in concrete and tested under four different loading patterns. The bond strength-slip curves of the bars were obtained and analyzed. The results showed that the maximum bond strengths under the repeated loads differed from those obtained under monotonic ones. In addition, noticeable differences in degradation of the bond strength with respect to the magnitude of slip were observed between the different bar types tested. On the basis of an image analysis of failure surfaces, they were attributed to the different bond failure mechanisms associated with the steel and GFRP bars.

Communications system evolutionary scenarios for Martian SEI support

NASA Technical Reports Server (NTRS)

Kwong, Paulman W.; Bruno, Ronald C.

1992-01-01

In the Space Exploration Initiative (SEI) mission scenarios, expanding human presence is the primary driver for high data rate Mars-Earth communications. To support an expanding human presence, the data rate requirement will be gradual, following the phased implementation over time of the evolving SEI mission. Similarly, the growth and evolution of the space communications infrastructure to serve this requirement will also be gradual to efficiently exploit the useful life of the installed communications infrastructure and to ensure backward compatibility with long-term users. In work conducted over the past year, a number of alternatives for supporting high data rate Mars-Earth communications have been analyzed with respect to their compatibility with gradual evolution of the space communications infrastructure. The alternatives include RF, millimeter wave (MMW), and optical implementations, and incorporate both surface and space-based relay terminals in the Mars and Earth regions. Each alternative is evaluated with respect to its ability to efficiently meet a projected growth in data rate over time, its technology readiness, and its capability to satisfy the key conditions and constraints imposed by evolutionary transition. As a result of this analysis, a set of attractive alternative communications architectures have been identified and described, and a road map is developed that illustrates the most rational and beneficial evolutionary paths for the communications infrastructure.

The SEIS Experiment: A Mars Seismic Package

NASA Technical Reports Server (NTRS)

Schibler, P.; Lognonne, P.; Giardini, D.; Banerdt, B.; Karczewski, J. F.; Mimoun, D.; Zweifel, P.; Pike, T.; Ammann, J.; Anglade, A.

2003-01-01

This experiment will integrate a VBB (Very Broad Band) two axis seismometer, a three axis Short Period seismometer and a series of environmental sensors for pressure, infra-sounds and temperature. IPGP (France) has the overall responsibility of the experiment and is responsible for the VBB and environmental sensors. ETHZ (Switzerland) is responsible for the electronics of the experiment and JPL (USA) for the SP (Short Period) sensors. SEIS instrument was first proposed and accepted for NetLander mission (and will also be in charge of data acquisition for SPICE experiment). This seismic package should also be proposed for future missions.

Insights into the Li Intercalation and SEI Formation on LiSi Nanoclusters

DOE PAGES

Hankins, Kie; Soto, Fernando A.; Balbuena, Perla B.

2017-01-01

We report a first-principles atomic level assessment of the lithiation and reactivity of pre-lithiated Si clusters. Density functional theory formation energy calculations reveal that the pre-lithiated Li 16Si 16 cluster exposed to two different Li fluxes can store Li between the concentrations of Li 2.5Si and Li 3.5Si. This increase in storage capacity is attributed to the start of an amorphization process in the cluster, and more importantly these results show that the intercalation reaction can be controlled by the flux of the Li-ions. However, in a real battery, the lithiation of the anode occurs simultaneously to the electrode-electrolyte reactions.more » Here we simulate the solid-electrolyte interphase (SEI) formation and simultaneous lithiation of a Li 16Si 16 cluster in contact with two different electrolyte solutions: one with pure ethylene carbonate (EC), and another with a 1 M solution of LiPF 6 in EC. Our ab initio molecular dynamics simulations show that the solvent and salt are decomposed leading to the initial stages of the SEI layer formation and large part of the added Li becomes part of the SEI. Interestingly, the pure EC solution results in lower storage capacity and higher reactivity, whereas the presence of the salt causes the opposite effect: higher lithiation and reduced reactivity.« less

First-Principles Analysis of Defect Thermodynamics and Ion Transport in Inorganic SEI Compounds: LiF and NaF

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

Yildirim, Handan; Kinaci, Alper; Chan, Maria K. Y.

The formation mechanism and composition of the solid electrolyte interphase (SEI) in lithium ion batteries has been widely explored. However, relatively little is known about the function of the SEI as a transport medium. Such critical information is directly relevant to battery rate performance, power loss, and capacity fading. To partially bridge this gap in the case of inorganic SEI compounds, we report herein the results of first-principles calculations on the defect thermodynamics, the dominant diffusion carriers, and the diffusion pathways associated with crystalline LiF and NaF, which are stable components of the SEI in Li-ion and Na-ion batteries, respectively.more » The thermodynamics of common point defects are computed, and the dominant diffusion carriers are determined over a voltage range of 0-4 V, corresponding to conditions relevant to both anode and cathode SEI's. Our analyses reveal that for both compounds, vacancy defects are energetically more favorable, therefore form more readily than interstitials, due to the close-packed nature of the crystal structures. However, the vacancy concentrations are very small for the diffusion processes facilitated by defects. Ionic conductivities are calculated as a function of voltage, considering the diffusion carrier concentration and the diffusion barriers as determined by nudged elastic band calculations. These conductivities are more than ten orders of magnitude smaller in NaF than in LiF. As compared to the diffusivity of Li in other common inorganic SEI compounds, such as Li2CO3 and Li2O,the cation diffusivity in LiF and NaF is quite low, with at least three orders of magnitude lower ionic conductivities. The results quantify the extent to which fluorides pose rate limitations in Li and Na batteries.« less

Fall 2014 SEI Research Review High Confidence Cyber Physical Systems

DTIC Science & Technology

2014-10-28

2014 Carnegie Mellon University Fall 2014 SEI Research Review High Confidence Cyber Physical Systems Software Engineering Institute Carnegie... Research Review de Niz Oct 28th, 2014 © 2014 Carnegie Mellon University Copyright 2014 Carnegie Mellon University This material is based upon work...Software Engineering Institute, a federally funded research and development center. Any opinions, findings and conclusions or recommendations expressed

SEI power source alternatives for rovers and other multi-kWe distributed surface applications

NASA Technical Reports Server (NTRS)

Bents, David J.; Kohout, L. L.; Mckissock, Barbara I.; Rodriguez, C. D.; Withrow, C. A.; Colozza, A.; Hanlon, James C.; Schmitz, Paul C.

1991-01-01

To support the Space Exploration Initiative (SEI), a study was performed to investigate power system alternatives for the rover vehicles and servicers that were subsequently generated for each of these rovers and servicers, candidate power sources incorporating various power generation and energy storage technologies were identified. The technologies were those believed most appropriate to the SEI missions, and included solar, electrochemical, and isotope systems. The candidates were characterized with respect to system mass, deployed area, and volume. For each of the missions a preliminary selection was made. Results of this study depict the available power sources in light of mission requirements as they are currently defined.

Self-healing SEI enables full-cell cycling of a silicon-majority anode with a coulombic efficiency exceeding 99.9%

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

Jin, Yang; Li, Sa; Kushima, Akihiro

Despite active developments, full-cell cycling of Li-battery anodes with >50 wt% Si (a Si-majority anode, SiMA) is rare. The main challenge lies in the solid electrolyte interphase (SEI), which when formed naturally (nSEI), is fragile and cannot tolerate the large volume changes of Si during lithiation/delithiation. An artificial SEI (aSEI) with a specific set of mechanical characteristics is henceforth designed; we enclose Si within a TiO 2 shell thinner than 15 nm, which may or may not be completely hermetic at the beginning. In situ TEM experiments show that the TiO 2 shell exhibits 5× greater strength than an amorphousmore » carbon shell. Void-padded compartmentalization of Si can survive the huge volume changes and electrolyte ingression, with a self-healing aSEI + nSEI. The half-cell capacity exceeds 990 mA h g -1 after 1500 cycles. To improve the volumetric capacity, we further compress SiMA 3-fold from its tap density (0.4 g cm -3) to 1.4 g cm -3, and then run the full-cell battery tests against a 3 mA h cm -2 LiCoO 2 cathode. Despite some TiO 2 enclosures being inevitably broken, 2× the volumetric capacity (1100 mA h cm -3) and 2× the gravimetric capacity (762 mA h g -1) of commercial graphite anode is achieved in stable full-cell battery cycling, with a stabilized areal capacity of 1.6 mA h cm -2 at the 100th cycle. The initial lithium loss, characterized by the coulombic inefficiency (CI), is carefully tallied on a logarithmic scale and compared with the actual full-cell capacity loss. In conclusion, it is shown that a strong, non-adherent aSEI, even if partially cracked, facilitates an adaptive self-repair mechanism that enables full-cell cycling of a SiMA, leading to a stabilized coulombic efficiency exceeding 99.9%.« less

Self-healing SEI enables full-cell cycling of a silicon-majority anode with a coulombic efficiency exceeding 99.9%

DOE PAGES

Jin, Yang; Li, Sa; Kushima, Akihiro; ...

2017-01-06

Despite active developments, full-cell cycling of Li-battery anodes with >50 wt% Si (a Si-majority anode, SiMA) is rare. The main challenge lies in the solid electrolyte interphase (SEI), which when formed naturally (nSEI), is fragile and cannot tolerate the large volume changes of Si during lithiation/delithiation. An artificial SEI (aSEI) with a specific set of mechanical characteristics is henceforth designed; we enclose Si within a TiO 2 shell thinner than 15 nm, which may or may not be completely hermetic at the beginning. In situ TEM experiments show that the TiO 2 shell exhibits 5× greater strength than an amorphousmore » carbon shell. Void-padded compartmentalization of Si can survive the huge volume changes and electrolyte ingression, with a self-healing aSEI + nSEI. The half-cell capacity exceeds 990 mA h g -1 after 1500 cycles. To improve the volumetric capacity, we further compress SiMA 3-fold from its tap density (0.4 g cm -3) to 1.4 g cm -3, and then run the full-cell battery tests against a 3 mA h cm -2 LiCoO 2 cathode. Despite some TiO 2 enclosures being inevitably broken, 2× the volumetric capacity (1100 mA h cm -3) and 2× the gravimetric capacity (762 mA h g -1) of commercial graphite anode is achieved in stable full-cell battery cycling, with a stabilized areal capacity of 1.6 mA h cm -2 at the 100th cycle. The initial lithium loss, characterized by the coulombic inefficiency (CI), is carefully tallied on a logarithmic scale and compared with the actual full-cell capacity loss. In conclusion, it is shown that a strong, non-adherent aSEI, even if partially cracked, facilitates an adaptive self-repair mechanism that enables full-cell cycling of a SiMA, leading to a stabilized coulombic efficiency exceeding 99.9%.« less

Sternal fractures occur most often in old cars to seat-belted drivers without any airbag often with concomitant spinal injuries: clinical findings and technical collision variables among 42,055 crash victims.

PubMed

Knobloch, Karsten; Wagner, Sebastian; Haasper, Carl; Probst, Christian; Krettek, Christian; Otte, Dietmar; Richter, Martinus

2006-08-01

The incidence and treatment of sternal fractures caused by traffic accidents is of increasing importance to ensure best possible outcomes. Analysis of technical indicators of the collision, preclinical, and clinical data of patients with sternal fractures from 1985 to 2004 among 42,055 injured patients was assessed by an Accident Research Unit. Two time groups were categorized: 1985 to 1994 (group A) versus 1995 to 2004 (group B). Of 42,055 patients, 267 (0.64%) suffered a sternal fracture. Regarding the vehicle type, the majority occurred after car accidents in 0.81% (251 of 31,183 patients), followed by 0.19% (5 of 2,633 patients) driving motorbike, and 0.11% (4 of 3,258 patients) driving a truck. Ninety-one percent wore a safety belt. Only 13% of all passengers suffering a sternal fracture had an airbag on board (33 of 255 car/trucks), with an airbag malfunction in 18%. The steering column was deformed in 39%, the steering wheel in 36%. Cars in the recent years were significantly older (group B, 7.67 +/- 5 years, versus group A, 5.88 +/- 5 years; p = 0.003). Cervical spine injuries are frequent (23% versus 22%), followed by multiple rib fractures (14% versus 12%) and lung contusions (12% versus 11%). We found 9 of 146 (6%) and 3 of 121 patients (3%) with heart contusion among the 267 sternal fractures. Maximal abbreviated injury scale score was 2.56 +/- 1.3 versus 2.62 +/- 1.3 (group A versus B, p = 0.349). Eighteen percent of patients were polytraumatized, with 11.2% dying at the scene, 2.3% in the hospital. Sternal fractures occur most often in old cars to seat-belted drivers often without any airbag. Severe multiple rib fractures and lung contusion are concomitant injuries in more than 10% each, indicating the severity of the crash. Over a 20-year period, the injury severity encountered was not different, with 18% polytrauma patients suffering sternal fractures.

75 FR 16731 - Young Dodge SEIS; Kootenai National Forest, Lincoln County, MT

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-02

... (SEIS) for the Young Dodge project. The Young Dodge project includes urban interface fuels treatments... management changes, including road decommissioning. The project is located in the Young Dodge planning... Wildland-Urban Interface, to decrease the likelihood that fires would become stand-replacing wildfires; (2...

Experimental Analysis of Dynamic Effects of FRP Reinforced Masonry Vaults.

PubMed

Corradi, Marco; Borri, Antonio; Castori, Giulio; Coventry, Kathryn

2015-11-27

An increasing interest in the preservation of historic structures has produced a need for new methods for reinforcing curved masonry structures, such as arches and vaults. These structures are generally very ancient, have geometries and materials which are poorly defined and have been exposed to long-term historical movements and actions. Consequently, they are often in need of repair or reinforcement. This article presents the results of an experimental study carried out in the laboratory and during on-site testing to investigate the behaviour of brick masonry vaults under dynamic loading strengthened with FRPs (Fiber Reinforced Polymers). For the laboratory tests, the brick vaults were built with solid sanded clay bricks and weak mortar and were tested under dynamic loading. The experimental tests were designed to facilitate analysis of the dynamic behaviour of undamaged, damaged and reinforced vaulted structures. On-site tests were carried out on an earthquake-damaged thin brick vault of an 18th century aristocratic residence in the city of L'Aquila, Italy. The provision of FRP reinforcement is shown to re-establish elastic behavior previously compromised by time induced damage in the vaults.

Experimental Analysis of Dynamic Effects of FRP Reinforced Masonry Vaults

PubMed Central

Corradi, Marco; Borri, Antonio; Castori, Giulio; Coventry, Kathryn

2015-01-01

An increasing interest in the preservation of historic structures has produced a need for new methods for reinforcing curved masonry structures, such as arches and vaults. These structures are generally very ancient, have geometries and materials which are poorly defined and have been exposed to long-term historical movements and actions. Consequently, they are often in need of repair or reinforcement. This article presents the results of an experimental study carried out in the laboratory and during on-site testing to investigate the behaviour of brick masonry vaults under dynamic loading strengthened with FRPs (Fiber Reinforced Polymers). For the laboratory tests, the brick vaults were built with solid sanded clay bricks and weak mortar and were tested under dynamic loading. The experimental tests were designed to facilitate analysis of the dynamic behaviour of undamaged, damaged and reinforced vaulted structures. On-site tests were carried out on an earthquake-damaged thin brick vault of an 18th century aristocratic residence in the city of L’Aquila, Italy. The provision of FRP reinforcement is shown to re-establish elastic behavior previously compromised by time induced damage in the vaults. PMID:28793697

Adaptive harvest management: Adjustments for SEIS 2013

USGS Publications Warehouse

Boomer, Scott; Johnson, Fred A.; Zimmerman, Guthrie S.

2015-01-01

This report provides a summary of revised methods and assessment results based on updated adaptive harvest management (AHM) protocols developed in response to the preferred alternative specified in the Final Supplemental Environmental Impact Statement on the Issuance of Annual Regulations Permitting the Hunting of Migratory Birds (SEIS; U.S. Department of the Interior 2013). We describe necessary changes to optimization procedures and decision processes for the implementation of AHM for midcontinent, eastern and western mallards (Anas platyrhynchos), northern pintails (Anas acuta), and scaup (Aythya affinis, A. marila) decision frameworks. We present this final report for communication purposes, and acknowledge that any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Potentials of Optical Damage Assessment Techniques in Automotive Crash-Concepts composed of FRP-Steel Hybrid Material Systems

NASA Astrophysics Data System (ADS)

Dlugosch, M.; Spiegelhalter, B.; Soot, T.; Lukaszewicz, D.; Fritsch, J.; Hiermaier, S.

2017-05-01

With car manufacturers simultaneously facing increasing passive safety and efficiency requirements, FRP-metal hybrid material systems are one way to design lightweight and crashworthy vehicle structures. Generic automotive hybrid structural concepts have been tested under crash loading conditions. In order to assess the state of overall damage and structural integrity, and primarily to validate simulation data, several NDT techniques have been assessed regarding their potential to detect common damage mechanisms in such hybrid systems. Significant potentials were found particularly in combining 3D-topography laser scanning and X-Ray imaging results. Ultrasonic testing proved to be limited by the signal coupling quality on damaged or curved surfaces.

Dynamic PIV measurement of a compressible flow issuing from an airbag inflator nozzle

NASA Astrophysics Data System (ADS)

Lee, Sang Joon; Jang, Young Gil; Kim, Seok; Kim, Chang Soo

2006-12-01

Among many equipment for passenger safety, the air bag system is the most fundamental and effective device for an automobile. The inflator housing is a main part of the curtain-type air bag system, which supplies high-pressure gases in pumping up the air bag-curtain which is increasingly being adapted in deluxe cars for protecting passengers from the danger of side clash. However, flow information on the inflator housing is very limited. In this study, we measure the instantaneous velocity fields of a high-speed compressible flow issuing from the exit nozzle of an inflator housing using a dynamic PIV system. From the velocity field data measured at a high frame-rate, we evaluate the variation of the mass flow rate with time. The dynamic PIV system consists of a high-repetition Nd:YLF laser, a high-speed CMOS camera, and a delay generator. The flow images are taken at 4000 fps with synchronization of the trigger signal for inflator ignition. From the instantaneous velocity field data of flow ejecting from the airbag inflator housing at the initial stage, we can see a flow pattern of broken shock wave front and its downward propagation. The flow ejecting from the inflator housing is found to have very high velocity fluctuations, with the maximum velocity at about 700 m/s. The time duration of the high-speed flow is very short, and there is no perceptible flow after 100 ms.

On the use of Space Station Freedom in support of the SEI - Life science research

NASA Technical Reports Server (NTRS)

Leath, K.; Volosin, J.; Cookson, S.

1992-01-01

The use of the Space Station Freedom (SSF) for life sciences research is evaluated from the standpoint of requirements for the Space Exploration Initiative (SEI). SEI life sciences research encompasses: (1) biological growth and development in space; (2) life support and environmental health; (3) physiological/psychological factors of extended space travel; and (4) space environmental factors. The platforms required to support useful study in these areas are listed and include ground-based facilities, permanently manned spacecraft, and the Space Shuttle. The SSF is shown to be particularly applicable to the areas of research because its facilities can permit the study of gravitational biology, life-support systems, and crew health. The SSF can serve as an experimental vehicle to derive the required knowledge needed to establish a commitment to manned Mars missions and colonization plans.

Connecting the irreversible capacity loss in Li-ion batteries with the electronic insulating properties of solid electrolyte interphase (SEI) components.

DOE PAGES

Leung, Kevin; Lin, Yu -Xiao; Liu, Zhe; ...

2016-01-01

The formation and continuous growth of a solid electrolyte interphase (SEI) layer are responsible for the irreversible capacity loss of batteries in the initial and subsequent cycles, respectively. In this article, the electron tunneling barriers from Li metal through three insulating SEI components, namely Li 2CO 3, LiF and Li 3PO 4, are computed by density function theory (DFT) approaches. Based on electron tunneling theory, it is estimated that sufficient to block electron tunneling. It is also found that the band gap decreases under tension while the work function remains the same, and thus the tunneling barrier decreases under tensionmore » and increases under compression. A new parameter, η, characterizing the average distances between anions, is proposed to unify the variation of band gap with strain under different loading conditions into a single linear function of η. An analytical model based on the tunneling results is developed to connect the irreversible capacity loss, due to the Li ions consumed in forming these SEI component layers on the surface of negative electrodes. As a result, the agreement between the model predictions and experimental results suggests that only the initial irreversible capacity loss is due to the self-limiting electron tunneling property of the SEI.« less

The SEIS Experiment for the Insight Mission: Development and management plan

NASA Astrophysics Data System (ADS)

Laudet, P.

2015-10-01

SEIS is a Mars seismometer, provided by CNES to JPL to be the threshold instrument of the next Mars mission, InSight, to be launched by NASA in March 2016. Discovery missions leads to a very strict frame of development, where schedule is driving development and qualification plans. We will explain how this constraint has been taken into account during development phases, until delivery of flight model, with a context of international cooperation without exchange of founds between partners.

Subsurface defect detection in first layer of pavement structure and reinforced civil engineering structure by FRP bonding using active infrared thermography

NASA Astrophysics Data System (ADS)

Dumoulin, Jean; Ibos, Laurent

2010-05-01

In many countries road network ages while road traffic and maintenance costs increase. Nowadays, thousand and thousand kilometers of roads are each year submitted to surface distress survey. They generally lean on pavement surface imaging measurement techniques, mainly in the visible spectrum, coupled with visual inspection or image processing detection of emergent distresses. Nevertheless, optimisation of maintenance works and costs requires an early detection of defects within the pavement structure when they still are hidden from surface. Accordingly, alternative measurement techniques for pavement monitoring are currently under investigation (seismic methods, step frequency radar). On the other hand, strengthening or retrofitting of reinforced concrete structures by externally bonded Fiber Reinforced Polymer (FRP) systems is now a commonly accepted and widespread technique. However, the use of bonding techniques always implies following rigorous installing procedures. To ensure the durability and long-term performance of the FRP reinforcements, conformance checking through an in situ auscultation of the bonded FRP systems is then highly suitable. The quality-control program should involve a set of adequate inspections and tests. Visual inspection and acoustic sounding (hammer tap) are commonly used to detect delaminations (disbonds) but are unable to provide sufficient information about the depth (in case of multilayered composite) and width of debonded areas. Consequently, rapid and efficient inspection methods are also required. Among the non destructive methods under study, active infrared thermography was investigated both for pavement and civil engineering structures through experiments in laboratory and numerical simulations, because of its ability to be also used on field. Pulse Thermography (PT), Pulse Phase Thermography (PPT) and Principal Component Thermography (PCT) approaches have been tested onto pavement samples and CFRP bonding on concrete

75 FR 65005 - Intent To Prepare a Draft Supplemental Environmental Impact Statement (SEIS), Mississippi Barrier...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-21

... Supplemental Environmental Impact Statement (SEIS), Mississippi Barrier Island Restoration, Mississippi Coastal... reduction, shoreline erosion, salt water intrusion and fish and wildlife preservation in three coastal... catastrophic damage to lives, property, and natural resources throughout coastal Mississippi. In response, the...

A strategy for enhancing shear strength and bending strength of FRP laminate using MWCNTs

NASA Astrophysics Data System (ADS)

Rawat, Prashant; Singh, K. K.

2016-09-01

Multi-wall carbon nanotubes (MWCNTs) promises to enhance mechanical properties exceptionally when it is doped with fiber reinforced polymer (FRP) composite. Glass fiber symmetrical laminate with eight layers of 4.0 mm thickness was fabricated by hand lay-up technique assisted by vacuum bagging method. Ply orientations for symmetrical laminate used [(0,90)/(+45,-45)/(+45,-45)/(0,90)//(90,0)/(+45,-45)/(+45,-45)/(90,0)]. MWCNTs reinforced three different samples (0 wt.%, 0.5 wt.% and 0.75 wt.% by weight) were tested on universal testing machine (UTM). Short beam strength test and inter laminar shear strength (ILSS) calculation have been done according to ASTM D2344 and ASTM D7264. UTM having maximum load capacity of 50 KN with loading rate of 0.1 mm/min to 50 mm/min was used for mechanical testing. Testing results justified that by adding 0.50 wt.% MWCNTs in symmetrical GFRP laminate can enhance inter laminar shear strength by 13.66% and bending strength by 44.22%.

Lithium Dendrite Suppression and Enhanced Interfacial Compatibility Enabled by an Ex Situ SEI on Li Anode for LAGP-Based All-Solid-State Batteries.

PubMed

Hou, Guangmei; Ma, Xiaoxin; Sun, Qidi; Ai, Qing; Xu, Xiaoyan; Chen, Lina; Li, Deping; Chen, Jinghua; Zhong, Hai; Li, Yang; Xu, Zhibin; Si, Pengchao; Feng, Jinkui; Zhang, Lin; Ding, Fei; Ci, Lijie

2018-06-06

The electrode-electrolyte interface stability is a critical factor influencing cycle performance of All-solid-state lithium batteries (ASSLBs). Here, we propose a LiF- and Li 3 N-enriched artificial solid state electrolyte interphase (SEI) protective layer on metallic lithium (Li). The SEI layer can stabilize metallic Li anode and improve the interface compatibility at the Li anode side in ASSLBs. We also developed a Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 -poly(ethylene oxide) (LAGP-PEO) concrete structured composite solid electrolyte. The symmetric Li/LAGP-PEO/Li cells with SEI-protected Li anodes have been stably cycled with small polarization at a current density of 0.05 mA cm -2 at 50 °C for nearly 400 h. ASSLB-based on SEI-protected Li anode, LAGP-PEO electrolyte, and LiFePO 4 (LFP) cathode exhibits excellent cyclic stability with an initial discharge capacity of 147.2 mA h g -1 and a retention of 96% after 200 cycles.

The Installation of Satellite Modems on SEIS-UK Supported Remote Seismic Deployments

NASA Astrophysics Data System (ADS)

Horleston, A. C.; Brisbourne, A.; Hawthorn, D.

2006-12-01

SEIS-UK, as the UK's NERC funded national seismic equipment facility, is frequently involved in large, often remote, temporary seismic networks (running for up to 2 years). Up till now all these deployments have been managed solely by on-site maintenance but now SEIS-UK is investing in a number of satellite modems. The Michrosat 2400 OEM Modems, provided by Wireless Innovations Ltd, will be integrated within Guralp DCM data-logger units and will be used to provide regular state-of-health reports from remote networks. They will also provide the user the facility to communicate with the deployed systems, apply configuration changes and request system re-boots. This should lead to less instrument down-time and allow for more focussed site visits and thus, hopefully, reduce the cost (and servicing time) of remote installations. The Michrosat Modems are relatively low-powered and draw a maximum current of 2.5A (at 4.4v) for a few microseconds when initialising a call, dropping to bursts of approximately 1A when transmitting. This makes them ideally suited to temporary deployments relying on solar charged battery power. We will present examples of the configuration and typical deployment of the modems and the types of data transmitted.

CU’s Department of Geological Sciences - Science Education Initiative Project (GEOL-SEI): A five-year plan for introducing and supporting an evidence-based and scientific approach to teaching

NASA Astrophysics Data System (ADS)

Arthurs, L.; Budd, D. A.

2009-12-01

The Science Education Initiative (SEI) at the University of Colorado at Boulder was conceived in 2006 with the goal of improving science education at the undergraduate level by changing the basic approach to teaching in science departments. Five departments were selected on a competitive basis for participation in the SEI. The SEI is operating as a five year plan with funding of ~$1 million/year for the five departments. The goal of the SEI is to implement sustainable department-level change for an evidence-based and scientific approach to teaching. Among the five departments receiving funding for discipline-specific SEI projects is the Department of Geological Sciences (GEOL-SEI). The GEOL-SEI has worked to transform geology courses beginning with lower division large enrollment courses and moving towards upper division courses. They are transformed on the basis of existing research into how people learn, and they are characterized by the use of learning goals and effective instructional approaches. Furthermore, a natural component of the transformation towards evidence-based and scientific approaches to teaching is geocognition and geoscience education research. This research focuses on how students think about geologic concepts (e.g. misconceptions) and the effectiveness of different instructional approaches (e.g. the implementation of instructional technologies, peer learning activities, homework, and labs). The research is conducted by post-doctoral fellows (with PhDs in geology and pedagogical training) in collaboration with the instructional faculty members. The directorate of CU’s Science Education Initiative provides the fellows with training useful for conducting the research. Currently, into the 4th year of its 5-year plan, the GEOL-SEI is working towards publishing its findings and exploring options for sustaining various changes made to courses and new departmental programs that support student learning (e.g. GEOL Tutoring & Study Room).

The SEIS Experiment for the InSight mission: status and performance expectations

NASA Astrophysics Data System (ADS)

Mimoun, David; Lognonne, Philippe; Banerdt, W. Bruce; Laudet, Philippe; De Raucourt, Sébastien; IJpelaan, Frans; Kerjean, Laurent; Perez, Rene; Pont, Gabriel; Sylvestre-Baron, Annick; verdier, Nicolas; Denise, Robert; Feldman, Jason; Hurst, Ken; Klein, Kerry; Giardini, Domenico; Zweifel, Peter; Pike, W. Tom; Calcutt, Simon; Bramanti, Christina

2015-04-01

The Insight NASA Discovery mission, led by the Jet Propulsion Laboratory, will deploy in September 2016 a very broadband seismometer on the Mars surface, SEIS (Seismic Experiment for Interior Structure). It is a hybrid 3-axes instrument, which encloses 3 very broadband oblique sensors and 3 short period sensors. The sensor assembly and its wind and thermal shield will by deployed on the Mars surface from the Phoenix-like spacecraft by a robotic arm (IDS). The acquisition system will be hosted in the spacecraft warm electronics box, and connected to the deployed sensor assembly by a tether. The SEIS experiment is provided by CNES, the French Space Agency that makes the coordination of a wide consortium including IPGP of Paris (SEIS PI Institution), Imperial College of London, Oxford University, MPS of Göttingen, ETH of Zürich, ISAE from Toulouse and the Jet Propulsion Laboratory of Pasadena. In addition to the seismometer, the Insight payload will also include a suite of instruments complementary to the seismometer, such as a precision temperature sensor, a micro-barometer, a magnetometer and a wind sensor, making it the first geophysical multi-parameter station on another planet. A heat flow sensor and geodetic measurements will provide additional science measurements, in order to constrain the internal structure of Mars. Several challenges have been overcome to design and realize the planetary seismometer, which will exhibit a noise of about 10-9 m/s2/sqrt(Hz) in its seismic bandwidth bandwidth (0.01-1 Hz) for the very broadband component. These challenges include a very efficient insulation from the external temperature variations, and a finely crafted mechanical design to keep the extreme sensitivity of the seismometer, while allowing enough robustness for the harsh mechanical environment encountered during the launch and landing sequences. Also, specific attention has been paid to understanding the various environment contributions to the noise figure. A

Conceptualizing ¬the Abstractions of Earthquakes Through an Instructional Sequence Using SeisMac and the Rapid Earthquake Viewer

NASA Astrophysics Data System (ADS)

Taber, J.; Hubenthal, M.; Wysession, M.

2007-12-01

Newsworthy earthquakes provide an engaging hook for students in Earth science classes, particularly when discussing their effects on people and the landscape. However, engaging students in an analysis of earthquakes that extends beyond death and damage, is frequently hampered by the abstraction of recorded ground motion data in the form of raw seismograms and the inability of most students to personally relate to ground accelerations. To overcome these challenges, an educational sequence has been developed using two software tools: SeisMac by Daniel Griscom, and the Rapid Earthquake Viewer (REV) developed by the University of South Carolina in collaboration with IRIS and DLESE. This sequence presents a unique opportunity for Earth Science teachers to "create" foundational experiences for students as they construction a framework of understanding of abstract concepts. The first activity is designed to introduce the concept of a three-component seismogram and to directly address the very abstract nature of seismograms through a kinesthetic experience. Students first learn to take the pulse of their classroom through a guided exploration of SeisMac, which displays the output of the laptop's built-in Sudden Motion Sensor (a 3-component accelerometer). This exploration allows students to view a 3-component seismogram as they move or tap the laptop and encourages them to propose and carry out experiments to explain the meaning of the 3-component seismogram. Once completed students are then asked to apply this new knowledge to a real 3-component seismogram printed from REV. Next the activity guides students through the process of identifying P and S waves and using SeisMac to connect the physical motion of the laptop to the "wiggles" they see on the SeisMac display and then comparing those to the "wiggles" they see on their seismogram. At this point students are more fully prepared to engage in an S-P location exercise such as those included in many state standards

Damaged Concrete Viaduct in an Italian Highway: Concrete Characterization and Possible Strengthening Techniques by FRP Applications in Comparison

NASA Astrophysics Data System (ADS)

Tittarelli, Francesca; Ruello, Maria Letizia; Capuani, Domenico; Aprile, Alessandra

2017-10-01

The “Fornello” viaduct in the Italian Orte-Ravenna highway (E45) is seriously damaged. In this paper, the concrete of the reinforced slab has been widely characterized to evaluate the level of damage and to identify the causes of degradation. No-destructive tests, as those based on ultrasonic waves, as well as chemical, physical and mechanical destructive tests have been carried out on specimens drawn from deteriorated and not deteriorated zones of the R/C bridge decks. Into the slab thickness, the concentration distribution of main anions has been quantified by ion chromatography. Porosimetry tests have been carried out to detect the resistance to freeze-thaw cycles of cement paste. Possible strengthening techniques by FRP applications have been compared.

Executive Overview of SEI MOSAIC: Managing for Success Using a Risk-Based Approach

DTIC Science & Technology

2007-03-01

and pro - vides the lens through which all potential outcomes are viewed and interpreted. Defining the con - text is thus an essential first step when...Success Analysis and Improvement Crite- ria (SEI MOSAIC)—a suite of advanced analysis methods for assessing complex, distributed pro - grams, processes...achieve that set of objectives, four ac- tivities must be executed in the order shown, while also adhering to any cost and schedule con - straints. Process

Stability and bifurcation for an SEIS epidemic model with the impact of media

NASA Astrophysics Data System (ADS)

Huo, Hai-Feng; Yang, Peng; Xiang, Hong

2018-01-01

A novel SEIS epidemic model with the impact of media is introduced. By analyzing the characteristic equation of equilibrium, the basic reproduction number is obtained and the stability of the steady states is proved. The occurrence of a forward, backward and Hopf bifurcation is derived. Numerical simulations and sensitivity analysis are performed. Our results manifest that media can regard as a good indicator in controlling the emergence and spread of the epidemic disease.

InSight/SEIS@Mars Educational program : Sharing the InSight NASA mission and the Seismic Discovery of Mars with a International Network of classes

NASA Astrophysics Data System (ADS)

Lognonne, P. H.; Berenguer, J. L.; Sauron, A.; Denton, P.; Carrer, D.; Taber, J.; Bravo, T. K.; Gaboriaud, A.; Houston Jones, J.; Banerdt, W. B.; Martinuzzi, J. M.

2015-12-01

The InSIght mission will deploy in September 2016 a Geophysical Station on Mars, equipped with a suite of geophysical instruments, including 3 axis Very Broad Band Seismometer, 3 axis Short Period Seismometer, 3 axis Flux gate Magnetometer, Heat flow probe, geodetic beacon, infrasound/microbarometer, wind sensors and cameras. As for all NASA missions, Children and teenagers will be associated to the mission in the framework of the K12 InSight program, part of it being associated to the SEIS instrument.The two faces of the InSight/SEIS Education program are directed toward the promotion of Space Technologies and of Space Science.For Space technologies, this has already started with the InSight Elysium Educational project. The goal of the project, supported by CNES and performed by Technical High School near Toulouse, was the fabrication of a full scale mockup of the lander (see more at https://jeunes.cnes.fr/fr/elysium-le-jumeau-terrestre-dinsight ). The mockup was exhibited during the June, 2015 Paris air show. More than 300 students participated to the Elysium project.For Space Science, this will be made with the SEIS@Mars Educational project. Its plan is to transmit the SEIS data to a network of several hundred of middle and high schools worldwide, associated to existing "seismo(graph) at school" programs in the United States (https://www.iris.edu/hq/sis), France (www.edusismo.org) Switzerland (www.seismoatschool.ethz.ch) and United Kingdom (http://www.bgs.ac.uk/schoolseismology/). If the transmission of these data to the SEIS@school network will be automatic after their release by the NASA Planetary Data System, an earlier transmission will be made, especially after mid 2017, but also before through the integration of selected Schools to the project activities: the selected classrooms will perform the same activities as the project scientists. They will have to process rapidly the proprietary data in order to identify MarsQuake(s) and will be allowed to perform

DigitSeis: A New Digitization Software and its Application to the Harvard-Adam Dziewoński Observatory Collection

NASA Astrophysics Data System (ADS)

Bogiatzis, P.; Altoé, I. L.; Karamitrou, A.; Ishii, M.; Ishii, H.

2015-12-01

DigitSeis is a new open-source, interactive digitization software written in MATLAB that converts digital, raster images of analog seismograms to readily usable, discretized time series using image processing algorithms. DigitSeis automatically identifies and corrects for various geometrical distortions of seismogram images that are acquired through the original recording, storage, and scanning procedures. With human supervision, the software further identifies and classifies important features such as time marks and notes, corrects time-mark offsets from the main trace, and digitizes the combined trace with an analysis to obtain as accurate timing as possible. Although a large effort has been made to minimize the human input, DigitSeis provides interactive tools for challenging situations such as trace crossings and stains in the paper. The effectiveness of the software is demonstrated with the digitization of seismograms that are over half a century old from the Harvard-Adam Dziewoński observatory that is still in operation as a part of the Global Seismographic Network (station code HRV and network code IU). The spectral analysis of the digitized time series shows no spurious features that may be related to the occurrence of minute and hour marks. They also display signals associated with significant earthquakes, and a comparison of the spectrograms with modern recordings reveals similarities in the background noise.

Towards a better understanding of the mechanisms controlling the durability of FRP composites in concrete

NASA Astrophysics Data System (ADS)

Kamal, Abu Sayed Md

Wide adoption by the construction industry of Fibre Reinforced Polymer (FRP) rebars - a relatively recent construction material that offers numerous advantages of corrosion resistance, higher strength, lighter weight, etc. over conventional reinforcing materials for concrete, such as steel - is at least partially impeded due to a lack of an effective long term in-service performance prediction model and relatively high initial costs. A reliable service life prediction model for FRP composites in concrete depends on a clear understanding of the transport mechanisms of potentially harmful chemical species into the FRP composites and their subsequent contribution to any potentially active degradation mechanism(s). To identify which mechanisms control the degradation of Glass Fibre Reinforced Polymers (GFRP) in alkaline environments, GFRP rebars were immersed into simulated concrete pore solutions and subjected to accelerated ageing tests (Phase 1). The conditioned samples were analyzed by various electron microscopy (SEM, EDS) and spectroscopic methods (FTIR). Analyses of these tests revealed that fibre-matrix debonding took place in few samples exposed to 75 °C (the highest temperature considered in this study), and tested after one year, despite the fact that the glass fibres and polymer matrix remained essentially intact and that no penetration of alkalis into the GFRP rebars was observed. Hence, this study shows that the Vinyl Ester (VE) polymer matrix used acts as an effective semi-permeable membrane by allowing the penetration of water while blocking alkali ions. The findings showing that most of the damage seems to be confined to the fibre-matrix interphase (or interface), under the considered test conditions, stimulated an investigation on the effects of sizing on the strength retention and water up-take of GFRP rebars in Phase 2 of the testing program. In order to study the effects of sizing on the properties of GFRP rebars, GFRP custom plane sheets with

Performance et caracterisation a l'arrachement des tiges en FRP de carbone utilisees pour renforcement au cisaillement par la methode ETS

NASA Astrophysics Data System (ADS)

Ammar Khodja, L'Hady

The rehabilitation and strengthening concrete structures in shear using composite materials such as externally bonded (EB) or near surface mounted rebar (NSMR) are well established techniques. However, debonding of these strengthening materials is still present and constitute the principal cause of shear failure of beams strengthened with composite materials. A new method called ETS (Embedded Through Section) was recently developed in order to avoid premature failures due to debonding of composite materials. The objective of this study is to highlight the importance and influence of important parameters on the behavior of CFRP bars anchorages subjected to pullout forces. These parameters are: concrete strength, anchorage length of CFRP bars, hole diameter in concrete, diameter of the bar and CFRP surface type (smooth versus sanded). Understanding the influence of these parameters on the relationship between the pullout force and the slip is paramount. This allows an accurate description of the behavior of all elements that contribute to the resistance of the CFRP bars pullout. A series of 25 specimens were subjected to pullout tests. The impact of these parameters on the pullout performance of CFRP rods is summarized in terms of failure mode, ultimate tensile strength and loading force slip relationship. The results of these investigations show that using the ETS method, failure of the anchors can be avoided by providing adequate anchorage length and concrete strength. The method provides greater confinement and thus leads to a substantial improvement in the performance of anchors. As a result, designers will be able to avoid failures that are due to debonding of anchors using thereby the full capabilities of reinforced beams strengthened in shear with EB FRP. Keywords: ETS method, shear, strengthening, anchor, slip, FRP, NSM.

Dissecting seipin function: the localized accumulation of phosphatidic acid at ER/LD junctions in the absence of seipin is suppressed by Sei1p(ΔNterm) only in combination with Ldb16p.

PubMed

Han, Sungwon; Binns, Derk D; Chang, Yu-Fang; Goodman, Joel M

2015-12-04

Seipin is required for the correct assembly of cytoplasmic lipid droplets. In the absence of the yeast seipin homolog Sei1p (formerly Fld1p), droplets are slow to bud from the endoplasmic reticulum, lack the normal component of proteins on their surface, are highly heterogeneous in size and shape, often bud into the nucleus, and promote local proliferation of the endoplasmic reticulum in which they become tangled. But the mechanism by which seipin catalyzes lipid droplet formation is still uncertain. Seipin prevents a localized accumulation of phosphatidic acid (PA puncta) at ER-droplet junctions. PA puncta were detected with three different probes: Opi1p, Spo20p(51-91) and Pah1p. A system of droplet induction was used to show that PA puncta were not present until droplets were formed; the puncta appeared regardless of whether droplets consisted of triacylglycerol or steryl ester. Deletion strains were used to demonstrate that a single phosphatidic acid-producing enzyme is not responsible for the generation of the puncta, and the puncta remain resistant to overexpression of enzymes that metabolize phosphatidic acid, suggesting that this lipid is trapped in a latent compartment. Suppression of PA puncta requires the first 14 amino acids of Sei1p (Nterm), a domain that is also important for initiation of droplet assembly. Consistent with recent evidence that Ldb16p and Sei1p form a functional unit, the PA puncta phenotype in the ldb16Δ sei1Δ strain was rescued by human seipin. Moreover, PA puncta in the sei1Δ strain expressing Sei1p(ΔNterm) was suppressed by overexpression of Ldb16p, suggesting a functional interaction of Nterm with this protein. Overexpression of both Sei1p and Ldb16p, but not Sei1p alone, is sufficient to cause a large increase in droplet number. However, Ldb16p alone increases triacylglycerol accumulation in the ldb16Δ sei1Δ background. We hypothesize that seipin prevents formation of membranes with extreme curvature at endoplasmic reticulum

Social Exclusion Index-for Health Surveys (SEI-HS): a prospective nationwide study to extend and validate a multidimensional social exclusion questionnaire.

PubMed

van Bergen, Addi P L; Hoff, Stella J M; Schreurs, Hanneke; van Loon, Annelies; van Hemert, Albert M

2017-03-14

Social exclusion (SE) refers to the inability of certain groups or individuals to fully participate in society. SE is associated with socioeconomic inequalities in health, and its measurement in routine public health monitoring is considered key to designing effective health policies. In an earlier retrospective analysis we demonstrated that in all four major Dutch cities, SE could largely be measured with existing local public health monitoring data. The current prospective study is aimed at constructing and validating an extended national measure for SE that optimally employs available items. In 2012, a stratified general population sample of 258,928 Dutch adults completed a version of the Netherlands Public Health Monitor (PHM) questionnaire in which 9 items were added covering aspects of SE that were found to be missing in our previous research. Items were derived from the SCP social exclusion index, a well-constructed 15-item instrument developed by the Netherlands Institute for Social Research (SCP). The dataset was randomly divided into a development sample (N =129,464) and a validation sample (N = 129,464). Canonical correlation analysis was conducted in the development sample. The psychometric properties were studied and compared with those of the original SCP index. All analyses were then replicated in the validation sample. The analysis yielded a four dimensional index, the Social Exclusion Index for Health Surveys (SEI-HS), containing 8 SCP items and 9 PHM items. The four dimensions: "lack of social participation", "material deprivation", "lack of normative integration" and "inadequate access to basic social rights", were each measured with 3 to 6 items. The SEI-HS showed adequate internal consistency for both the general index and for two of four dimension scales. The internal structure and construct validity of the SEI-HS were satisfactory and similar to the original SCP index. Replication of the SEI-HS in the validation sample confirmed its

76 FR 336 - Intent To Prepare a Supplemental Environmental Impact Statement (SEIS) for PacRim Coal's Proposed...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-04

... Environmental Impact Statement (SEIS) for PacRim Coal's Proposed Chuitna Coal Project AGENCY: U.S. Army Corps of... Chuitna Coal Project. It is anticipated that the Environmental Protection Agency (EPA), the Native Village... the Alaska Surface Coal Mining Control and Reclamation Act (ASCMCRA) permit, which governs all aspects...

Scientific Exploration of Induced SeisMicity and Stress (SEISMS)

NASA Astrophysics Data System (ADS)

Savage, Heather M.; Kirkpatrick, James D.; Mori, James J.; Brodsky, Emily E.; Ellsworth, William L.; Carpenter, Brett M.; Chen, Xiaowei; Cappa, Frédéric; Kano, Yasuyuki

2017-11-01

Several major fault-drilling projects have captured the interseismic and postseismic periods of earthquakes. However, near-field observations of faults immediately before and during an earthquake remain elusive due to the unpredictable nature of seismicity. The Scientific Exploration of Induced SeisMicity and Stress (SEISMS) workshop met in March 2017 to discuss the value of a drilling experiment where a fault is instrumented in advance of an earthquake induced through controlled fluid injection. The workshop participants articulated three key issues that could most effectively be addressed by such an experiment: (1) predictive understanding of the propensity for seismicity in reaction to human forcing, (2) identification of earthquake nucleation processes, and (3) constraints on the factors controlling earthquake size. A systematic review of previous injection experiments exposed important observational gaps in all of these areas. The participants discussed the instrumentation and technological needs as well as faults and tectonic areas that are feasible from both a societal and scientific standpoint.

NSPWG-recommended safety requirements and guidelines for SEI nuclear propulsion

NASA Technical Reports Server (NTRS)

Marshall, Albert C.; Sawyer, J. C., Jr.; Bari, Robert A.; Brown, Neil W.; Cullingford, Hatice S.; Hardy, Alva C.; Lee, James H.; Mcculloch, William H.; Niederauer, George F.; Remp, Kerry

1992-01-01

An interagency Nuclear Safety Policy Working Group (NSPWG) was chartered to recommend nuclear safety policy, requirements, and guidelines for the Space Exploration Initiative (SEI) nuclear propulsion program to facilitate the implementation of mission planning and conceptual design studies. The NSPWG developed a top-level policy to provide the guiding principles for the development and implementation of the nuclear propulsion safety program and the development of safety functional requirements. In addition, the NSPWG reviewed safety issues for nuclear propulsion and recommended top-level safety requirements and guidelines to address these issues. Safety requirements were developed for reactor start-up, inadvertent criticality, radiological release and exposure, disposal, entry, and safeguards. Guidelines were recommended for risk/reliability, operational safety, flight trajectory and mission abort, space debris and meteoroids, and ground test safety. In this paper the specific requirements and guidelines will be discussed.

Development and characterization of soy-based epoxy resins and pultruded FRP composites

NASA Astrophysics Data System (ADS)

Zhu, Jiang

This dissertation focuses on the development, manufacture and characterization of novel soy-based epoxy FRP composites. Use of alternative epoxy resin systems derived from a renewable resource holds potential for low cost raw materials for the polymer and composite industries. Epoxidized Allyl Soyate (EAS) and Epoxidized Methyl Soyate (EMS) were developed from soybean oil with two chemical modification procedures: transesterification and epoxidation. This research investigates the curing characteristics and thermal and mechanical properties of the neat soyate resin systems. The derived soyate resins have higher reactivity and superior performance compared to commercially available epoxidized soybean oil. An efficient two-step curing method was developed in order to utilize these soyate resins to their full potential. The epoxy co-resin systems with varied soyate resin content were successfully used to fabricate composite material through pultrusion. The pultrusion resin systems with 30 wt% soyate resins yielded improved, or comparable mechanical properties with neat commercial resins. A finite element analysis of the heat transfer and curing process was performed to study the processing characterization on glass/epoxy composite pultrusion. This model can be used to establish baseline process variables and will benefit subsequent optimization. This research demonstrates that soy-based resins, especially EAS, show considerable promise as an epoxy resin supplement for use in polymer and composite structural applications. The new products derived from soybean oil can provide competitive performance, low cost and environmental advantages.

Simultaneous Formation of Artificial SEI Film and 3D Host for Stable Metallic Sodium Anodes.

PubMed

Zhang, Di; Li, Bin; Wang, Shuai; Yang, Shubin

2017-11-22

Metallic sodium is a promising anode for sodium-based batteries, owing to its high theoretical capacity (1165 mAh g -1 ) and low potential (-2.714 V vs standard hydrogen electrode). However, the growth of sodium dendrites and the infinite volume change of metallic sodium during sodium striping/plating result in a low Coulombic efficiency and poor cycling stability, generating a safety hazard of sodium-based batteries. Here, an efficient approach was proposed to simultaneously generate an artificial SEI film and 3D host for metallic sodium based on a conversion reaction (CR) between sodium and MoS 2 (4Na + MoS 2 = 2Na 2 S + Mo) at room temperature. In the resultant sodium-MoS 2 hybrid after the conversion reaction (Na-MoS 2 (CR)), the production Na 2 S is homogeneously dispersed on the surface of metallic sodium, which can act as an artificial SEI film, efficiently preventing the growth of sodium dendrites; the residual MoS 2 nanosheets can construct a 3D host to confine metallic sodium, accommodating largely the volume change of sodium. Consequently, the Na-MoS 2 (CR) hybrid exhibits very low overpotential of 25 mV and a very long cycle stability more than 1000 cycles. This novel strategy is promising to promote the development of metal (lithium, sodium, zinc)-based electrodes.

[Injuries in the throat-nose-ear area by automobile air bags].

PubMed

Klask, J

2001-03-01

Airbags are successful in avoiding or in reducing serious injuries caused by motor vehicle accidents. On the other hand airbag deployment has led to a new kind of injuries. Only a few publications about that item exist. The experiences made with two patients after airbag deployment are described. The relevant literature is discussed. Two patients after airbag injuries were examined. The face of the first patient hit a regularly expanding airbag. Afterwards his nose was obviously deformed. In the other case both front airbags of a car burst triggered by a frontal crash. The symptoms of this patient were painful itching skinlesions in his face, unilateral hearing loss and tinnitus. The first described patient had a clinical and radiological provable fracture of his nasal bone with a frontal impression. The facial skin of the other patient was etched by the filling gas of the airbags. He was also suffering from an acoustic trauma. These cases are compared to other cases found in the literature. Oto-rhino-laryngological injuries can be caused by airbag deployment, especially by bursting airbags. Beside of outward injuries like dermatological hurts and fractures of the facial skeleton also more serious and life-threatening traumata can occur with damage of the cervical spine and upper airway. Moreover otologic handicaps like temporary or permanent hearing loss, tinnitus, vertigo, otalgia and tympanic membrane perforations are possible consequences.

Unmanned Ground Vehicle for Autonomous Non-Destructive Testing of FRP Bridge Decks

NASA Astrophysics Data System (ADS)

Klinkhachorn, P.; Mercer, A. Scott; Halabe, Udaya B.; GangaRao, Hota V. S.

2007-03-01

Current non-destructive techniques for defect analysis of FRP bridge decks have a narrow scope. These techniques are very good at detecting certain types of defects but are not robust enough to detect all defects by themselves. For example, infrared thermography (IRT) can detect air filled defects and Ground Penetrating Radar (GPR) is good at detecting water filled ones. These technologies can be combined to create a more robust defect detection scheme. To accomplish this, an Unmanned Ground Vehicle (UGV) has been designed that incorporates both IR and GPR analysis to create a comprehensive defect map of a bridge deck. The UGV autonomously surveys the deck surface and acquires data. The UGV has two 1.5 GHz ground coupled GPR antennas that are mounted on the front of the UGV to collect GPR data. It also incorporates an active heating source and a radiometric IR camera to capture IR images of the deck, even in less than ideal weather scenarios such as cold cloudy days. The UGV is designed so that it can collect data in an assembly line fashion. It moves in 1 foot increments. When moving, it collects GPR data from the two antennas. When it stops it heats a section of the deck. The next time it stops to heat a section, the IR camera is analyzing the preheated deck section while preparing for the next section. Because the data is being continually collected using this method, the UGV can survey the entire deck in an efficient and timely manner.

Results of SEI Independent Research and Development Projects and Report on Emerging Technologies and Technology Trends

DTIC Science & Technology

2004-10-01

Top-Level Process for Identification and Analysis of Safety-Related Re- quirements 4.4 Collaborators The primary SEI team members were Don Firesmith...Graff, M. & van Wyk, K. Secure Coding Principles & Practices. O’Reilly, 2003. • Hoglund, G. & McGraw, G. Exploiting Software: How to Break Code. Addison...Eisenecker, U.; Glück, R.; Vandevoorde, D.; & Veldhuizen , T. “Generative Programming and Active Libraries (Extended Abstract)” <osl.iu.edu/~tveldhui/papers

Severe soft tissue injuries of the upper extremity in motor vehicle crashes involving partial ejection: the protective role of side curtain airbags.

PubMed

Kaufman, Robert; Fraade-Blanar, Laura; Lipira, Angelo; Friedrich, Jeffrey; Bulger, Eileen

2017-05-01

Partial ejection (PE) of the upper extremity (UE) can occur in a motor vehicle crash (MVC) resulting in complex and severe soft tissue injuries (SSTI). This study evaluated the relationship between partial ejection and UE injuries, notably SSTIs, in MVCs focusing on crash types and characteristics, and further examined the role of side curtain airbags (SCABs) in the prevention of partial ejection and reducing SSTI of the UE. Weighted data was analyzed from the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) from 1993 to 2012. Logistic regression models were used to assess the relationship of PE with SSTI of the UE and the effect of SCABs in both nearside impacts and rollover collisions. Crash Injury Research and Engineering Network (CIREN) case studies illustrated PE involving SSTI of the UE, and long term treatment. Rollover and nearside impact collisions had the highest percentages of partial ejection, with over half occurring in rollover collisions. Annually over 800 SSTIs of the UE occurred in all MVCs. For nearside lateral force impacts, a multivariable analysis adjusting for belt use and delta V showed a 15 times (OR 15.35, 95% CI 4.30, 54.79) greater odds of PE for occupants without SCABs compared to those with a SCAB deployment. No occupants (0 of 51,000) sustained a SSTI of the UE when a SCAB deployed in nearside impacts, compared to 0.01% (114 of 430,000) when SCABs were unavailable or did not deploy. In rollover collisions, a multivariable analysis adjusted for number of quarter turns and belt use showed 3 times the odds (OR 3.02, 95% CI 1.22, 7.47) of PE for occupants without SCABs compared to those with a SCAB deployment. Just 0.17% (32 of 19,000) of the occupants sustained a SSTI of the UE in rollovers with a SCAB deployment, compared to 0.53% (2294 of 431,000) of the occupants when SCABs were unavailable or did not deploy. CIREN case studies illustrated the injury causation of SSTI of the UE due to partial ejection, and the

Computational Exploration of the Li-Electrode|Electrolyte Interface in the Presence of a Nanometer Thick Solid-Electrolyte Interphase Layer [Computational exploration of the Li-electrode|electrolyte interface complicated by a nanometer thin solid-electrolyte interphase (SEI) layer

DOE PAGES

Li, Yunsong; Leung, Kevin; Qi, Yue

2016-09-30

A nanometer thick passivation layer will spontaneously form on Li-metal in battery applications due to electrolyte reduction reactions. This passivation layer in rechargeable batteries must have “selective” transport properties: blocking electrons from attacking the electrolytes, while allowing Li + ion to pass through so the electrochemical reactions can continue. The classical description of the electrochemical reaction, Li + + e → Li 0, occurring at the Li-metal|electrolyte interface is now complicated by the passivation layer and will reply on the coupling of electronic and ionic degrees of freedom in the layer. We consider the passivation layer, called “solid electrolyte interphasemore » (SEI)”, as “the most important but the least understood in rechargeable Li-ion batteries,” partly due to the lack of understanding of its structure–property relationship. In predictive modeling, starting from the ab initio level, we find that it is an important tool to understand the nanoscale processes and materials properties governing the interfacial charge transfer reaction at the Li-metal|SEI|electrolyte interface. Here, we demonstrate pristine Li-metal surfaces indeed dissolve in organic carbonate electrolytes without the SEI layer. Based on joint modeling and experimental results, we point out that the well-known two-layer structure of SEI also exhibits two different Li + ion transport mechanisms. The SEI has a porous (organic) outer layer permeable to both Li + and anions (dissolved in electrolyte), and a dense (inorganic) inner layer facilitate only Li + transport. This two-layer/two-mechanism diffusion model suggests only the dense inorganic layer is effective at protecting Li-metal in electrolytes. This model suggests a strategy to deconvolute the structure–property relationships of the SEI by analyzing an idealized SEI composed of major components, such as Li 2CO 3, LiF, Li 2O, and their mixtures. After sorting out the Li+ ion diffusion carriers

Computational Exploration of the Li-Electrode|Electrolyte Interface in the Presence of a Nanometer Thick Solid-Electrolyte Interphase Layer [Computational exploration of the Li-electrode|electrolyte interface complicated by a nanometer thin solid-electrolyte interphase (SEI) layer

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

Li, Yunsong; Leung, Kevin; Qi, Yue

A nanometer thick passivation layer will spontaneously form on Li-metal in battery applications due to electrolyte reduction reactions. This passivation layer in rechargeable batteries must have “selective” transport properties: blocking electrons from attacking the electrolytes, while allowing Li + ion to pass through so the electrochemical reactions can continue. The classical description of the electrochemical reaction, Li + + e → Li 0, occurring at the Li-metal|electrolyte interface is now complicated by the passivation layer and will reply on the coupling of electronic and ionic degrees of freedom in the layer. We consider the passivation layer, called “solid electrolyte interphasemore » (SEI)”, as “the most important but the least understood in rechargeable Li-ion batteries,” partly due to the lack of understanding of its structure–property relationship. In predictive modeling, starting from the ab initio level, we find that it is an important tool to understand the nanoscale processes and materials properties governing the interfacial charge transfer reaction at the Li-metal|SEI|electrolyte interface. Here, we demonstrate pristine Li-metal surfaces indeed dissolve in organic carbonate electrolytes without the SEI layer. Based on joint modeling and experimental results, we point out that the well-known two-layer structure of SEI also exhibits two different Li + ion transport mechanisms. The SEI has a porous (organic) outer layer permeable to both Li + and anions (dissolved in electrolyte), and a dense (inorganic) inner layer facilitate only Li + transport. This two-layer/two-mechanism diffusion model suggests only the dense inorganic layer is effective at protecting Li-metal in electrolytes. This model suggests a strategy to deconvolute the structure–property relationships of the SEI by analyzing an idealized SEI composed of major components, such as Li 2CO 3, LiF, Li 2O, and their mixtures. After sorting out the Li+ ion diffusion carriers

Automatically produced FRP beams with embedded FOS in complex geometry: process, material compatibility, micromechanical analysis, and performance tests

NASA Astrophysics Data System (ADS)

Gabler, Markus; Tkachenko, Viktoriya; Küppers, Simon; Kuka, Georg G.; Habel, Wolfgang R.; Milwich, Markus; Knippers, Jan

2012-04-01

The main goal of the presented work was to evolve a multifunctional beam composed out of fiber reinforced plastics (FRP) and an embedded optical fiber with various fiber Bragg grating sensors (FBG). These beams are developed for the use as structural member for bridges or industrial applications. It is now possible to realize large scale cross sections, the embedding is part of a fully automated process and jumpers can be omitted in order to not negatively influence the laminate. The development includes the smart placement and layout of the optical fibers in the cross section, reliable strain transfer, and finally the coupling of the embedded fibers after production. Micromechanical tests and analysis were carried out to evaluate the performance of the sensor. The work was funded by the German ministry of economics and technology (funding scheme ZIM). Next to the authors of this contribution, Melanie Book with Röchling Engineering Plastics KG (Haren/Germany; Katharina Frey with SAERTEX GmbH & Co. KG (Saerbeck/Germany) were part of the research group.

Impact Response of US Army and National Football League Helmet Pad Systems

DTIC Science & Technology

2011-01-04

encased in an inflatable airbag with relief channels to neighboring pads in the helmet. The inflatable airbag is for comfort and provides no...s impact filter artifact airbag effect 22 compressed as far as the simple cylinder impact simulation suggests, reducing the peak acceleration

Examination of Air Force Crash Damaged or Disabled Aircraft Recovery Program Resourcing

DTIC Science & Technology

2011-06-01

Positioning for Lift ................................................................................... 2 Figure 4. 26 and 15-Ton Airbags Under Wing...15 Figure 5. Manufacture Depiction of Airbag System...lifting capacities are calculated at an airbag working pressure of seven pounds per square inch. The lifting bag example below is from AGE

Design and Characterization of a Space Based Chromotomographic Hyperspectral Imaging Experiment

DTIC Science & Technology

2011-06-01

shaker there are two sets of airbags . Underneath the side fixtures are two valves on each side of the shaker assembly which will be used during...the next step to inflate all 4 airbags . Watch closely to observe the side panels rise as the airbag inflates. Stop inflating when the panel is...2.12. RCM CONNECT the adapter to the hose and INFLATE all 4 airbags . _____2.13. RCM CONNECT the air supply to the shaker assembly. TURN ON air supply

Restraint use and lower extremity fractures in frontal motor vehicle collisions.

PubMed

Estrada, Lance S; Alonso, Jorge E; McGwin, Gerald; Metzger, Jesse; Rue, Loring W

2004-08-01

Seat belts and air bags have been shown to significantly reduce morbidity and mortality following MVCs. Research suggests that restraint use does not protect against lower extremity fracture; however, no population-based studies of this association exist. The purpose of this study is to compare the effectiveness of combined seat belt and airbag restraint systems with airbag alone, seat belt alone, and no restraints with respect to incidence and location of lower extremity fractures. A retrospective analysis of front seat occupants involved in police-reported, tow-away frontal MVCs was conducted using data from the 1995 through 2000 National Automotive Sampling System (NASS). Incidence and relative risk (RR) of fracture to specific bony regions were measured according to seat belt use and airbag deployment. Compared with unrestrained occupants, occupants restrained with airbag only had significantly higher risk for all types of lower extremity fractures whereas those occupants restrained with either seat belt only or seat belt and airbag had lower risk of fracture. The greatest difference was seen with tibia/fibula fractures in airbag only (RR, 2.14) but this trend continued to be significant with femur and pelvic fractures (RR, 1.13 and 1.23, respectively). While airbags may reduce the risk of death when used alone or in combination with seat belts, the results of this study demonstrate that air bags increase the risk of lower extremity fractures when used as the sole method of passenger protection. Also, they may do so differentially according to skeletal region. This data strongly support the consideration of developing accessory knee bolster airbags to prevent the "submarining" or sliding under the airbag that may be responsible for this finding.

Mars deep internal structure determination using Phobos tide measurement strategy with the SEIS/InSight experiment

NASA Astrophysics Data System (ADS)

Pou, Laurent; Mimoun, David; Garcia, Raphaël; Lognonné, Philippe; Banerdt, William Bruce; Karatekin, Özgür; Dehant, Véronique; Zhu, Ping

2016-04-01

The Insight NASA Discovery mission, led by the Jet Propulsion Laboratory, will deploy in 2018 a very broadband seismometer on the Mars surface, SEIS (Seismic Experiment for Interior Structure). It is a hybrid 3-axes instrument, which encloses 3 very broadband oblique sensors and 3 short period sensors. The sensor assembly and its wind and thermal shield will by deployed on the Mars surface from the Phoenix-like spacecraft by a robotic arm (IDS). The acquisition system will be hosted in the spacecraft warm electronics box, and connected to the deployed sensor assembly by a tether. The SEIS experiment is provided by CNES, the French Space Agency that makes the coordination of a wide consortium including IPGP of Paris, ETH of Zürich, the Jet Propulsion Laboratory of Pasadena, MPS of Göttingen, Imperial College of London, and ISAE from Toulouse. One of the mission goals is to determine the deep internal structure of Mars in order to improve our models on the formation and evolution of telluric planets. In particular, the SEIS experiment aims at assessing the state (solid or liquid) of the planet core together with its size. This will be possible using the Phobos tide, a solid tide on Mars induced by one of its natural satellite, Phobos. As it orbits the planet, Phobos creates a small displacement of the Martian surface which will be measured to determine the absolute amplitude of one of the tide main harmonics which depends on Mars internal structure through the gravimetric factor γ2 (a combination of the gravitational and displacement Love numbers) at a frequency range around 50 μHz. Since Phobos orbital properties are already well-known, comparing these measurements with existing proposed models of Mars allows us to refine the previous estimations of the Mars core state and diameter. Reliable assessment of the core state will be possible if the Phobos tide absolute amplitude is measured with a precision of 2.5 10-11 m/s2 at 50μHz, making noise determination and

SM1.3 Seismic Centers Data Acquisition: an introduction to Antelope, EarthWorm, SeisComP and their usage around the world

NASA Astrophysics Data System (ADS)

Pesaresi, Damiano; Sleeman, Reinoud

2010-05-01

Many medium to big size seismic data centers around the world are facing the same question: which software to use to acquire seismic data in real-time? A home-made or a commercial one? Both choices have pros and cons. The in-house development of software usually requires an increased investment in human resources rather than a financial investment. However, the advantage of fully accomplishing your own needs could be put in danger when the software engineer quits the job! Commercial software offers the advantage of being maintained, but it may require both a considerable financial investment and training. The main seismic software data acquisition suites available nowadays are the public domain SeisComP and EarthWorm packages and the commercial package Antelope. Nanometrics, Guralp and RefTek also provide seismic data acquisition software, but they are mainly intended for single station/network acquisition. Antelope is a software package for real-time acquisition and processing of seismic network data, with its roots in the academic seismological community. The software is developed by Boulder Real Time Technology (BRTT) and commercialized by Kinemetrics. It is used by IRIS affiliates for off-line data processing and it is the main acquisition tool for the USArray program and data centers in Europe like the ORFEUS Data Center, OGS (Italy), ZAMG (Austria), ARSO (Slovenia) and GFU (Czech Republic). SeisComP was originally developed for the GEOFON global network to provide a system for data acquisition, data exchange (SeedLink protocol) and automatic processing. It has evolved into to a widely distributed, networked seismographic system for data acquisition and real-time data exchange over Internet and is supported by ORFEUS as the standard seismic data acquisition tool in Europe. SeisComP3 is the next generation of the software and was developed for the German Indonesian Tsunami Early Warning System (GITEWS). SeisComP is licensed by GFZ (free of charge) and

R & D of smart FRP-OFBG-based steel strand and its application in monitoring of prestressing loss for RC

NASA Astrophysics Data System (ADS)

Zhou, Zhi; Zhou, Hui; Huang, Ying; Ou, Jinping

2008-03-01

The long-term monitoring and performance evaluation techniques for the steel strand based pre-stressed structures are still not mature yet, especially for the prestressing loss monitoring and prediction. The main problem of this issue is lack of reliable monitoring techniques. To resolve this problem, in this paper, a new kind of quasi-distributed smart steel strand based on FRP-OFBG(Fiber Reinforced Polymer-Optical Fiber Bragg Grating) has been developed and its pre-stress monitoring principle has been also given. The test of the post-tension pre-stressed concrete beam with bonded tendons and its tensioning experiments have been conducted. And the prestressing loss of the steel strands has been monitored using the FBG in it. Researches results indicate that this kind of smart steel strand can monitor both instant loss and permanent loss of the prestressing successfully, and it can preferably describe the pre-stress loss state of the pre-stressed structure. Compared with the traditional monitoring instrument, this kind of smart steel strand owns distinct advantages and broad application foregrounds.

Function of fusion regulatory proteins (FRPs) in immune cells and virus-infected cells.

PubMed

Tsurudome, M; Ito, Y

2000-01-01

Two molecules that regulate cell fusion have been identified and designated fusion regulatory protein-1 (FRP-1) and FRP-2. FRP-1 is a complex composed of a glycosylated heavy chain and a nonglycosylated light chain that are disulfide linked. FRP-1 heavy chain is identical to 4F2/CD98 heavy chain, whereas FRP-2 is identical to integrin alpha3 subunit. The FRP-1 heavy chain is a multifunctional molecule: that is, fusion regulator, amino acid transporter, integrin regulator, comitogenic factor, Na+-Ca2+ exchanger, oncogenic protein, and so on. Several aspects of the structure and function of the FRP-1 system are reviewed: fusion regulatory molecular mechanisms, cross-talk between the FRP-1 and integrin, the FRP-1 system as amino acid transporter, and FRP-1-mediated T-cell activation. The FRP-1 system is involved in virus-mediated cell fusion and multinucleated giant cell formation of blood monocytes. Monoclonal antibodies against human FRP-1 heavy chain induce polykaryocytes that have properties as osteoclasts. Multiple steps participate in molecular mechanisms regulating cell fusion. The FRP-1 heavy chain supports amino acid transport activity and the FRP-1 light chains have recently been cloned as amino acid transporters that require association with the heavy chain to exhibit their activity. Novel pathways for monocyte-dependent regulation of T-cell activation have recently been found that are mediated by the FRP-1 system. In conclusion, the FRP-1 molecules are essential factors for basic cellular functions.

KENNEDY SPACE CENTER, FLA. - On Mars Exploration Rover 1 (MER-1) , air bags are installed on the lander. The airbags will inflate to cushion the landing of the spacecraft on the surface of Mars. When it stops bouncing and rolling, the airbags will deflate and retract, the petals will open to bring the lander to an upright position, and the rover will be exposed. NASA's twin Mars Exploration Rovers are designed to study the history of water on Mars. These robotic geologists are equipped with a robotic arm, a drilling tool, three spectrometers, and four pairs of cameras that allow them to have a human-like, 3D view of the terrain. Each rover could travel as far as 100 meters in one day to act as Mars scientists' eyes and hands, exploring an environment where humans can't yet go. MER-1 is scheduled to launch June 25 as MER-B aboard a Delta II rocket from Cape Canaveral Air Force Station.

NASA Image and Video Library

2003-05-10

KENNEDY SPACE CENTER, FLA. - On Mars Exploration Rover 1 (MER-1) , air bags are installed on the lander. The airbags will inflate to cushion the landing of the spacecraft on the surface of Mars. When it stops bouncing and rolling, the airbags will deflate and retract, the petals will open to bring the lander to an upright position, and the rover will be exposed. NASA's twin Mars Exploration Rovers are designed to study the history of water on Mars. These robotic geologists are equipped with a robotic arm, a drilling tool, three spectrometers, and four pairs of cameras that allow them to have a human-like, 3D view of the terrain. Each rover could travel as far as 100 meters in one day to act as Mars scientists' eyes and hands, exploring an environment where humans can't yet go. MER-1 is scheduled to launch June 25 as MER-B aboard a Delta II rocket from Cape Canaveral Air Force Station.

Enterotoxin Gene Cluster-Encoded SEI and SElN from Staphylococcus aureus Isolates are Crucial for the Induction of Human Blood Cell Proliferation and Pathogenicity in Rabbits.

PubMed

Roetzer, Andreas; Gruener, Corina S; Haller, Guenter; Beyerly, John; Model, Nina; Eibl, Martha M

2016-10-28

Among the toxin family of bacterial superantigens, the six members of the enterotoxin gene cluster (egc) seem to have unusual characteristics. They are present in the majority of Staphylococcus aureus strains, but their role in disease remains uncertain. We assessed secretion levels, immunogenicity, and toxicity of native and recombinant egc proteins. After having developed enzyme-linked immunosorbent assays, we found different quantities of egc proteins secreted by bacterial isolates. Supernatants induced proliferation of human peripheral blood mononuclear cells. However, purified recombinant egc proteins were shown to have differing superantigenicity potentials. Immunization with identical amounts of all members of egc, and the prominent toxic agent SEB, resulted in neutralizing antisera. Two egc proteins, SEI and SE l N, were found to play a predominant role within the cluster. Both displayed the highest potential to activate blood cells, and were essential to be neutralized in supernatants. The application of a supernatant of a strain bearing only egc was sufficient for a lethal outcome in a rabbit model. Again, neutralization of SEI and SE l N led to the survival of all tested animals. Finally, nanogram amounts of purified rSEI and rSE l N led to lethality in vivo, pointing out the importance of both as virulence determinants among egc superantigens.

Enterotoxin Gene Cluster-Encoded SEI and SElN from Staphylococcus aureus Isolates are Crucial for the Induction of Human Blood Cell Proliferation and Pathogenicity in Rabbits

PubMed Central

Roetzer, Andreas; Gruener, Corina S.; Haller, Guenter; Beyerly, John; Model, Nina; Eibl, Martha M.

2016-01-01

Among the toxin family of bacterial superantigens, the six members of the enterotoxin gene cluster (egc) seem to have unusual characteristics. They are present in the majority of Staphylococcus aureus strains, but their role in disease remains uncertain. We assessed secretion levels, immunogenicity, and toxicity of native and recombinant egc proteins. After having developed enzyme-linked immunosorbent assays, we found different quantities of egc proteins secreted by bacterial isolates. Supernatants induced proliferation of human peripheral blood mononuclear cells. However, purified recombinant egc proteins were shown to have differing superantigenicity potentials. Immunization with identical amounts of all members of egc, and the prominent toxic agent SEB, resulted in neutralizing antisera. Two egc proteins, SEI and SElN, were found to play a predominant role within the cluster. Both displayed the highest potential to activate blood cells, and were essential to be neutralized in supernatants. The application of a supernatant of a strain bearing only egc was sufficient for a lethal outcome in a rabbit model. Again, neutralization of SEI and SElN led to the survival of all tested animals. Finally, nanogram amounts of purified rSEI and rSElN led to lethality in vivo, pointing out the importance of both as virulence determinants among egc superantigens. PMID:27801832

Real-life fatal outcome in car-to-car near-side impacts--implications for improved protection considering age and crash severity.

PubMed

Sunnevang, Cecilia; Rosén, Erik; Bostrom, Ola

2009-04-01

Recent studies have shown that current side airbags, protecting head and chest, are saving lives in near-side impacts (Kahane 2007; McCartt and Kyrychenko 2007). The aim of this study was to analyze NASS/CDS real-life data on fatal trauma in near-side car-to-car crashes, stratified by age into non-senior and senior occupants. Furthermore, a hypothetical model explaining side airbag effectiveness as a function of lateral delta-v was presented. The model together with the field data was then used to demonstrate further enhancement of side airbag restraint performance. Weighted NASS/CDS data from 1994 to 2006 for front seat occupants in near-side car-to-car impacts was used to calculate the exposure, incidence, and risk of fatal trauma with respect to lateral delta-v. The dataset was also divided into non-senior (10-59 years) and senior (age > or = 60 years) occupants. The hypothetical model was created to adjust the NASS/CDS data to represent a car fleet fully equipped with current side airbag protection. The model was then used to evaluate the increase in effectiveness of improved side airbag protection achieved by increasing the lateral delta-v in the range where the airbag have most mitigating effect, increasing the airbag protection level within the delta-v range currently tested, and a combination of the two approaches. From the NASS/CDS data, the median delta-v for fatal injury was 37 km/h for the total sample. When stratified with respect to age, the median delta-v for fatal injury was 41 km/h for non-seniors and 28 km/h for senior occupants. The exposures for both age groups were similar. However, the fatal incidence showed a difference in delta-v range between non-senior and senior occupants. Applying the airbag model increased the median delta-v to 40 km/h for the total sample and 47 and 30 km/h for non-seniors and seniors, respectively. Current side airbag systems offer very good protection for non-senior occupants up to delta-v 40 km/h. Though still high

SHARD - a SeisComP3 module for Structural Health Monitoring

NASA Astrophysics Data System (ADS)

Weber, B.; Becker, J.; Ellguth, E.; Henneberger, R.; Herrnkind, S.; Roessler, D.

2016-12-01

Monitoring building and structure response to strong earthquake ground shaking or human-induced vibrations in real-time forms the backbone of modern structural health monitoring (SHM). The continuous data transmission, processing and analysis reduces drastically the time decision makers need to plan for appropriate response to possible damages of high-priority buildings and structures. SHARD is a web browser based module using the SeisComp3 framework to monitor the structural health of buildings and other structures by calculating standard engineering seismology parameters and checking their exceedance in real-time. Thresholds can be defined, e.g. compliant with national building codes (IBC2000, DIN4149 or EC8), for PGA/PGV/PGD, response spectra and drift ratios. In case thresholds are exceeded automatic or operator driven reports are generated and send to the decision makers. SHARD also determines waveform quality in terms of data delay and variance to report sensor status. SHARD is the perfect tool for civil protection to monitor simultaneously multiple city-wide critical infrastructure as hospitals, schools, governmental buildings and structures as bridges, dams and power substations.

MOTOR VEHICLE SAFETY: NHTSA’s Ability to Detect and Recall Defective Replacement Crash Parts Is Limited

DTIC Science & Technology

2001-01-01

incorporate airbags , under the used vehicle provision. NHTSA has not developed such standards because it has not identified significant problems with...might incorporate airbags . NHTSA has not developed such standards because it has not identified significant problems with occupant restraint systems...Appendix I: Scope and Methodology 24 Appendix II: State Legislation Governing Aftermarket Crash Parts and Recycled Airbags 27 Figures Figure 1: Replacement

Blast Technologies

DTIC Science & Technology

2011-06-27

Development Generic Hull Testing Airbag and Sensor Technology Development Blast Data Recorder Specifications and Fielding Numerical Model Improvement...seat designs, airbag and restraint systems, and energy absorbing flooring solutions  Vehicle event data recorders for collecting highly accurate...treatments.  Airbag or comparable technologies such as bolsters.  Sensors that can detect and deploy/trigger interior treatments within the timeframe of a

The Multi-factor Predictive Seis &Gis Model of Ecological, Genetical, Population Health Risk and Bio-geodynamic Processes In Geopathogenic Zones

NASA Astrophysics Data System (ADS)

Bondarenko, Y.

I. Goal and Scope. Human birth rate decrease, death-rate growth and increase of mu- tagenic deviations risk take place in geopathogenic and anthropogenic hazard zones. Such zones create unfavourable conditions for reproductive process of future genera- tions. These negative trends should be considered as a protective answer of the com- plex biosocial system to the appearance of natural and anthropogenic risk factors that are unfavourable for human health. The major goals of scientific evaluation and de- crease of risk of appearance of hazardous processes on the territory of Dnipropetrovsk, along with creation of the multi-factor predictive Spirit-Energy-Information Space "SEIS" & GIS Model of ecological, genetical and population health risk in connection with dangerous bio-geodynamic processes, were: multi-factor modeling and correla- tion of natural and anthropogenic environmental changes and those of human health; determination of indicators that show the risk of destruction structures appearance on different levels of organization and functioning of the city ecosystem (geophys- ical and geochemical fields, soil, hydrosphere, atmosphere, biosphere); analysis of regularities of natural, anthropogenic, and biological rhythms' interactions. II. Meth- ods. The long spatio-temporal researches (Y. Bondarenko, 1996, 2000) have proved that the ecological, genetic and epidemiological processes are in connection with de- velopment of dangerous bio-geophysical and bio-geodynamic processes. Mathemat- ical processing of space photos, lithogeochemical and geophysical maps with use of JEIS o and ERDAS o computer systems was executed at the first stage of forma- tion of multi-layer geoinformation model "Dnipropetrovsk ARC View GIS o. The multi-factor nonlinear correlation between solar activity and cosmic ray variations, geophysical, geodynamic, geochemical, atmospheric, technological, biological, socio- economical processes and oncologic case rate frequency, general and primary

Deliberate modification of the solid electrolyte interphase (SEI) during lithiation of magnetite, Fe 3O 4: impact on electrochemistry

DOE PAGES

Bock, David C.; Marschilok, Amy C.; Takeuchi, Kenneth J.; ...

2017-11-20

Here, magnetite is a conversion anode material displaying multi-electron transfer during lithiation and delithiation. The solid electrolyte interphase (SEI) on magnetite, Fe 3O 4, electrodes for lithium ion batteries was deliberately modified through the use of fluoroethylene carbonate (FEC) electrolyte additive, improving both capacity retention and rate capability. Analysis showed reduction of FEC at higher voltage compared to non-fluorinated solvents with formation of a modified lithium flouride containing electrode surface.

Teaching with Real-time Earthquake Data in jAmaSeis

NASA Astrophysics Data System (ADS)

Bravo, T. K.; Coleman, B.; Taber, J.

2011-12-01

Earthquakes can capture the attention of students and inspire them to explore the Earth. The Incorporated Research Institutions in Seismology (IRIS) and Moravian College are collaborating to develop cross-platform software (jAmaSeis) that enables students to access real-time earthquake waveform data. Users can record their own data from several different types of educational seismometers, and they can obtain data in real-time from other jAmaseis users nationwide. Additionally, the ability to stream data from the IRIS Data Management Center (DMC) is under development. Once real-time data is obtained, users of jAmaseis can study seismological concepts in the classroom. The user interface of the software is carefully designed to lead students through the steps to interrogate seismic data following a large earthquake. Users can process data to determine characteristics of seismograms such as time of occurrence, distance from the epicenter to the station, magnitude, and location (via triangulation). Along the way, the software provides graphical clues to assist student interpretations. In addition to the inherent pedagogical features of the software, IRIS provides pre-packaged data and instructional activities to help students learn the analysis steps. After using these activities, students can apply their skills to interpret seismic waves from their own real-time data.

Assessment of the state of the art in life support environmental control for SEI

NASA Technical Reports Server (NTRS)

Simonds, Charles H.; Noyes, Gary P.

1992-01-01

This paper defines the types of technology that would be used in a lunar base for environmental control and life support system and how it might relate to in situ materials utilization (ISMU) for the Space Exploration Initiative (SEI). There are three types of interaction between ISMU and the Environmental Control and Life Support System (ECLSS): (1) ISMU can reduce cost of water, oxygen, and possibly diluent gasses provided to ECLSS--a corollary to this fact is that the availability of indigenous resources can dramatically alter life support technology trade studies; (2) ISMU can use ECLSS waste systems as a source of reductant carbon and hydrogen; and (3) ECLSS and ISMU, as two chemical processing technologies used in spacecraft, can share technology, thereby increasing the impact of technology investments in either area.

Guidelines for the use of fiberglass reinforced plastic in utility FGD systems. [Flue gas desulfurization (FGD); contains glossary

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

Rapoza, R.J.; Vollmer, H.R.; Haberly, K.L.

1992-11-01

Fiberglass reinforced plastic (FRP) materials offer excellent corrosion-resistant properties and long-term cost advantages compared to exotic alloys or organic lining systems. This guideline document provides potential buyers of FRP FGD (flue gas desulfurization) equipment with enough knowledge of FRP materials and methods to make informed decisions when procuring FRP equipment or services. It is divided into the following chapters: application criteria, procurement strategies, FRP basics, guidelines for designing FRP equipment, quality management. A glossary and manufacturers information/recommendations are included.

Mars pathfinder lander deployment mechanisms

NASA Technical Reports Server (NTRS)

Gillis-Smith, Greg R.

1996-01-01

The Mars Pathfinder Lander employs numerous mechanisms, as well as autonomous mechanical functions, during its Entry, Descent and Landing (EDL) Sequence. This is the first US lander of its kind, since it is unguided and airbag-protected for hard landing using airbags, instead of retro rockets, to soft land. The arrival condition, location, and orientation of the Lander will only be known by the computer on the Lander. The Lander will then autonomously perform the appropriate sequence to retract the airbags, right itself, and open, such that the Lander is nearly level with no airbag material covering the solar cells. This function uses two different types of mechanisms - the Airbag Retraction Actuators and the Lander Petal Actuators - which are designed for the high torque, low temperature, dirty environment and for limited life application. The development of these actuators involved investigating low temperature lubrication, Electrical Discharge Machining (EDM) to cut gears, and gear design for limited life use.

Business Case Analysis: Reconfiguration of the Frederick Memorial Healthcare System Courier Service

DTIC Science & Technology

2008-05-13

from each specimen. This figure alone clearly supports the existence of the FMH courier service. The problem , rather, lies in the efficiency and...investigated, to include the Hyundai Accent, Chevrolet Aveo, and the Honda Fit. Each vehicle was evaluated on cost, fuel efficiency, predicted reliability...P175/65R14 Tires Temporary Spare Tire SAFETY Driver Front Airbag and Front Passenger Airbag with Advanced Airbag System 3 Point Driver & Fr Pass

Proceedings of the ATB Model Users Group Conference Held in Phoenix, Arizona on 8-9 February 1996.

DTIC Science & Technology

1996-02-09

8217 0.3 Cards Harness Belt Geomietry iEVRNMNTIHamess F.8 Cards Airbag Geometry EVRNMNT/ Airbags D.4 Cards Spring/Dampers EVIRNIVNTISpring-Dampers 0.8 Cards...Conference Units of Measurement o Specify Length, Force, & Time Units o English - Inches, Pounds, Seconds - Most commonly used - Field width problems ...Proceedings of the 1996 ATB Model Users’ Group Conference 22 Airbags Reaction Panels "Contacting Body DeploymentPrmy Point Reaction Panel Spring-Dampers

UAV Swarm Attack: Protection System Alternatives for Destroyers

DTIC Science & Technology

2012-12-01

Tactical Rocket-Propelled Grenade Airbag Protection System TRL - Technology Readiness Level UAV - Unmanned Aerial Vehicle USN - United States...com- posed of 62 DDGs is $2.014 billion dollars for the 12 year life cycle. J. REACTIVE ARMOR The Tactical Rocket-Propelled Grenade (RPG) Airbag ...Protection System (TRAPS) system involves ‘close-in’ protection using airbags located around a vehicle to minimize the damage from RPGs. This system was

Under-Body Blast Mitigation: Stand-Alone Seat Safety Activation System

DTIC Science & Technology

2014-04-01

Restraints, Airbags or other protection systems) to mitigate injury to the occupant during the onset of the event. Injuries may occur as soon as 2.5 ms...cost-effective sensor to accurately and consistently deploy airbags and other pyrotechnic restraint systems based on accelerometers and other...Circuitry are critically important in order to activate the initiators of air bags and pyrotechnic restraint system such as airbags at the very first

Aircraft Survivability. Summer 2011

DTIC Science & Technology

2011-01-01

airbag systems and the DEA, offer unique advantages for improving rotorcraft crashworthiness, either as stand-alone systems or in conjunction with a...deployment methods were studied with the goal of achieving equivalent deployment times as external airbag systems. Since 2006, experimental evaluation of...Y., Gansman B., and Bradney C., “Rotorcraft External Airbag Protection System,” Proceedings of the AHS 62nd Annual Forum, Phoenix AZ, May 2006. 5

Smart fiber-reinforced polymer anchorage system with optical fiber Bragg grating sensors

NASA Astrophysics Data System (ADS)

Huang, Minghua; Zhou, Zhi; He, Jianping; Chen, Genda; Ou, Jinping

2010-03-01

Civil Engineers have used fiber reinforced polymer (FRP) with high axial strength as an effective and economical alternative to steel in harsh corrosion environments. However, the practical applications of FRP are limited by the tendency of FRP materials to fail suddenly under lateral pressure and surface injury. For example, shear stresses result from the bonding effect between the FRP material and the structure of the anchorage system due to the lower shear strength of FRP. This paper proposes a novel smart FRP anchorage system with embedded optical fiber Bragg grating (FBG) sensors to monitor the axial strain state and accordingly the interfacial shear stress, as well as the interfacial damage characteristics of FRP anchorage. One FBG sensor was embedded in an FRP rod outside the anchorage region to evaluate the properties of the material, and seven FBG sensors were distributed along the rod in the anchor to monitor the axial strain variations and study the interfacial mechanical behaviors of the smart FRP anchorage under a static pulling load. The experimental results agreed well with theoretical predictions. The smart FRP anchorage system with optical FBG sensors proves effective and practical for monitoring the long-term mechanical behavior of FRP anchorage systems.

Behaviour of fibre reinforced polymer confined reinforced concrete columns under fire condition

NASA Astrophysics Data System (ADS)

Chowdhury, Ershad Ullah

In recent years, fibre reinforced polymer (FRP) materials have demonstrated enormous potential as materials for repairing and retrofitting concrete bridges that have deteriorated from factors such as electro-chemical corrosion and increased load requirements. However, concerns associated with fire remain an obstacle to applications of FRP materials in buildings and parking garages due to FRP's sensitivity to high temperatures as compared with other structural materials and to limited knowledge on their thermal and mechanical behaviour in fire. This thesis presents results from an ongoing study on the fire performance of FRP materials, fire insulation materials and systems, and FRP wrapped reinforced concrete columns. The overall goal of the study is to understand the fire behaviour of FRP materials and FRP strengthened concrete columns and ultimately, provide rational fire safety design recommendations and guidelines for FRP strengthened concrete columns. A combined experimental and numerical investigation was conducted to achieve the goals of this research study. The experimental work consisted of both small-scale FRP material testing at elevated temperatures and full-scale fire tests on FRP strengthened columns. A numerical model was developed to simulate the behaviour of unwrapped reinforced concrete and FRP strengthened reinforced concrete square or rectangular columns in fire. After validating the numerical model against test data available in literature, it was determined that the numerical model can be used to analyze the behaviour of concrete axial compressive members in fire. Results from this study also demonstrated that although FRP materials experience considerable loss of their mechanical and bond properties at temperatures somewhat below the glass transition temperature of the resin matrix, externally-bonded FRP can be used in strengthening concrete structural members in buildings, if appropriate supplemental fire protection system is provided over

Estimation of Biomass Burning Emissions by Fusing Fire Radiative Power Observed from Polar-orbiting and Geostationary Satellites across the Continental United States

NASA Astrophysics Data System (ADS)

Li, F.; Zhang, X.; Kondragunta, S.

2016-12-01

Trace gases and aerosols released from biomass burning significantly disturb the energy balance of the Earth and also degrade regional air quality. However, biomass burning emissions (BBE) have been poorly estimated using the traditional bottom-up approach because of the substantial uncertainties in the burned area and fuel loads. Recently, Fire Radiative Power (FRP) derived from satellite fire observations enables the estimation of BBE at multiple spatial scales in near real time. Nonetheless, it is very challenging to accurately produce reliable FRP diurnal cycles from either polar-orbiting satellites or geostationary satellites for the calculation of the temporally integrated FRP, Fire Radiative Energy (FRE). Here we reconstruct FRP diurnal cycles by fusing FRP observed from polar-orbiting and geostationary satellites and estimate BBE from 2011 to 2015 across the Continental United States. Specifically, FRP from the Geostationary Operational Environmental Satellite (GOES) is preprocessed and calibrated using the collocated and concurred observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) over Landsat TM burn scars. The climatologically diurnal FRP curves are then calculated from the calibrated GOES FRP for the 25 Bailey's ecoregions. By fitting MODIS FRP and the calibrated GOES FRP to the climatological curves, FRP diurnal cycles are further reconstructed for individual days at a 0.25-degree grid. Both FRE estimated from FRP diurnal cycles and ecoregion specified FRE combustion rates are used to estimate hourly BBE. The estimated BBE is finally evaluated using QFED and GFED4.0 inventories and emissions modeled using Landsat TM 30m burn severities and 30m fuel loading from Fuel Characteristic Classification System. The results show that BBE estimates are greatly improved by using the reconstructed FRP diurnal cycles from high temporal (GOES) and high spatial resolution (MODIS) FRP observations.

Gas evolution from cathode materials: A pathway to solvent decomposition concomitant to SEI formation.

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

Browning, Katie L; Baggetto, Loic; Unocic, Raymond R

This work reports a method to explore the catalytic reactivity of electrode surfaces towards the decomposition of carbonate solvents [ethylene carbonate (EC), dimethyl carbonate (DMC), and EC/DMC]. We show that the decomposition of a 1:1 wt% EC/DMC mixture is accelerated over certain commercially available LiCoO2 materials resulting in the formation of CO2 while over pure EC or DMC the reaction is much slower or negligible. The solubility of the produced CO2 in carbonate solvents is high (0.025 grams/mL) which masks the effect of electrolyte decomposition during storage or use. The origin of this decomposition is not clear but it ismore » expected to be present on other cathode materials and may affect the analysis of SEI products as well as the safety of Li-ion batteries.« less

The Effect of Driver Age On The Incidence And Severity Of Upper Extremity Injuries Due To Second Generation Front Air Bag Deployment

PubMed Central

Marshall, Rafael; Hunting, Katherine; McKay, Mary Pat

2010-01-01

This study used NHTSA NASS/CDS data to examine whether advancing age was associated with a higher incidence and severity of front airbag-related upper extremity injury (UEI). Using a retrospective cohort design we analyzed weighted data from 1998–2007 for. The study population consisted of lap/shoulder belted people over 16 years of age who were driving passenger vehicles with model years 1998–2003 and were involved in a frontal crash where their front airbag deployed. Drivers who were ejected, involved in a vehicle rollover, or accompanied by a passenger sitting directly behind them were omitted. The exposure variable was age and the outcome variables were UEI incidence and severity. Associations were adjusted for gender, seat track position, vehicle type, vehicle weight, intrusion, and delta-v. Logistic regressions were performed using SAS survey procedures to account for the complex survey design. Overall, 42% of drivers sustained an UEI. Advancing age was associated with a higher incidence (p<0. 0001) and severity (p<0. 0001) of UEI. Nineteen percent of drivers sustained an UEI related to the airbag. No significant differences in the incidence or severity of airbag-related UEI were found between young drivers and older driver age groups. The degree of severity due to airbag-related UEI was generally minor. The majority of airbag-related UEI appeared to shift slightly from abrasions to contusions with aging. These results indicate that UEI due to depowered airbag deployment is common but not disproportionately high among older drivers, and injury severity is generally minor across all age groups. PMID:21050604

Identification of a candidate oncogene SEI-1 within a minimal amplified region at 19q13.1 in ovarian cancer cell lines.

PubMed

Tang, Terence C-M; Sham, Jonathan S T; Xie, Dan; Fang, Yan; Huo, Ke-Ke; Wu, Qiu-Liang; Guan, Xin-Yuan

2002-12-15

High-level amplification of DNA sequence at 19q13.1 is one of the frequent genetic alterations in ovarian cancer. In an attempt to verify the minimal amplified region (MAR) at 19q13.1 and to identify the target oncogenes, 49 probes within a region from D19S425 to D19S907 ( approximately 19.5 cM) were used to survey the amplification status in four ovarian cancer cell lines that have been confirmed as containing amplification at 19q13.1. Two separated overlapping MARs, MAR1 (approximately 200 kb) and MAR2 (approximately 1.1 Mb), were identified at 19q13.1. Two candidate oncogenes, AKT2 and SEI-1, were identified in MAR2. Amplification and overexpression of these two genes in four ovarian cancer cell lines were confirmed by Southern and Northern blot analyses. The proliferation-related function of AKT2 and SEI-1 suggests that both genes are likely to be biological targets of an amplification event at 19q13.1 in ovarian cancer and to play important roles in ovarian tumorigenesis.

SeisCube Instrument and Environment Considerations for the Didymos System Geophysical Exploration

NASA Astrophysics Data System (ADS)

Cadu, Alexandre; Murdoch, Naomi; Mimoun, David; Karatekin, Ozgur; Garica, Raphaël F.; Carrasco, Jose A.; De Quiros, Francisco G.; Vasseur, Hugues; Eubanks, Marshall; Radley, Charles; Ritter, Birgit; Dehant, Veronique

2016-04-01

In the context of the Asteroid Impact & Deviation Assessment (AIDA) mission proposed by ESA and NASA, the Asteroid Geophysical Explorer (AGEX) mission concept has been selected for a preliminary study phase. Two 3-Unit CubeSats are embedded into the AIM probe and released into the asteroid binary system [1]. SeisCube will be deployed close to the secondary to reach its surface at a low relative velocity in order to stay on the ground after several rebounds, in a similar way that is foreseen for Mascot-2. The purpose of SeisCube is to provide information about the surface, the sub-surface and the internal structure of the asteroid, by analyzing rebound acceleration profile and seismic activity [2]. We describe the considered instrumentation necessary to fulfill the science objectives (gravimeters, accelerometers, geophones, etc.) in terms of measurement dynamics, frequency ranges, acquisition methods and other common budgets for space equipment. We also present the environment considerations which have to be taken into account for the platform and payload designs. The thermal aspect will be particularly discussed since it is a major issue in the airless body exploration [3] [4]. It implies some modifications in the CubeSat structure, integration and thermal regulation to ensure survival and operations under extreme conditions at the asteroid surface. We then describe the platform subsystems needed to ensure the operations after the deployment and the associated budgets and accommodation. As a direct consequence of the previous topics, we will finally discuss the possible trades-off to satisfy the main science requirements and the associated concept of operations. [1] O. Karatekin, D. Mimoun, J. A. Carrasco, N. Murdoch, A. Cadu, R. F. Garcia, F. G. De Quiros, H. Vasseur, B. Ritter, M. Eubanks, C. Radley and V. Dehant, "The Asteroid Geophysical Explorer (AGEX): Proposal to explore Didymos system using Cubsats," in European Geophysical Union, 2016. [2] N. Murdoch, A

Seating positions and children's risk of dying in motor vehicle crashes

PubMed Central

Braver, E.; Whitfield, R.; Ferguson, S.

1998-01-01

Objectives—To determine the effects of seating position, combined with restraint use and airbag status, on children's risk of dying in crashes. Methods—Using 1988–95 data from the United States Fatality Analysis Reporting System, risk of death was compared among front and rear seated passengers aged 12 and younger who were involved in fatal crashes for different categories of restraint use and in vehicles with and without passenger airbags. Results—Restrained children in rear seats had the lowest risk of dying in fatal crashes. Among children seated in the rear, risk of death was reduced 35% in vehicles without any airbags, 31% in vehicles equipped only with driver airbags, and 46% in vehicles with passenger airbags. Both restrained and unrestrained children aged 0–12 were at lower risk of dying in rear seats. Rear seats also afforded additional protection to children aged 5–12 restrained only with lap belts compared with lap/shoulder belted children in front seats. Children were about 10–20% less likely to die in rear center than in rear outboard positions. Conclusions—Parents and others who transport children should be strongly encouraged to place infants and children in rear seats whether or not vehicles have airbags. Existing laws requiring restraint use by children should be strengthened and actively enforced. PMID:9788087

Fracture Toughness and Shear Strength of the Bonded Interface Between an Aluminium Alloy Skin and a FRP Patch

NASA Astrophysics Data System (ADS)

Kumar, Prashant; Shinde, Prakash Sonyabapu; Bhoyar, Gaurav

2018-05-01

The existing techniques to determine the fracture properties such as critical energy release rate in mode I (GIc) and mode II (GIIc) of an interface between two sheets of same material were modified to determine these properties between the sheets of dissimilar materials and thickness. In addition, the interface shear strength (ISS) was also determined. Experiments were carried out on the specimens made of a pre-cracked thin aluminium alloy skin and a Fiber reinforced polymer (FRP) patch. Two kinds of surface preparation of the aluminium skin were employed; (i) emery-paper roughened surface (ERS) and (ii) Sodium Hydroxide (NaOH) treated surface (NTS). GIc of ERS specimen was found to be 36.1 J/m2, while it was found to be much higher for NTS specimens, that is, 87.3 J/m2. GIIc was found to be 282.4 J/m2 for ERS specimens and much higher as 734.5 J/m2 for NTS specimens. ISS was determined as 32.6 MPa for ERS specimen and significantly higher for NTS specimen, that is, 44.5 MPa. The micrographs obtained from a field emission-scanning electron microscope (FE-SEM) and the surface roughness test showed that the NTS was significantly rougher than the ERS, explaining the higher values of all the three kinds of NTS specimens.

Quasi-plane-hypothesis of strain coordination for RC beams seismically strengthened with externally-bonded or near-surface mounted fiber reinforced plastic

NASA Astrophysics Data System (ADS)

Ren, Zhenhua; Zeng, Xiantao; Liu, Hanlong; Zhou, Fengjun

2013-03-01

The application of fiber reinforced plastic (FRP), including carbon FRP and glass FRP, for structural repair and strengthening has grown due to their numerous advantages over conventional materials such as externally bonded reinforcement (EBR) and near-surface mounted (NSM) strengthening techniques. This paper summarizes the results from 21 reinforced concrete beams strengthened with different methods, including externally-bonded and near-surface mounted FRP, to study the strain coordination of the FRP and steel rebar of the RC beam. Since there is relative slipping between the RC beam and the FRP, the strain of the FRP and steel rebar of the RC beam satisfy the quasi-plane-hypothesis; that is, the strain of the longitudinal fiber that parallels the neutral axis of the plated beam within the scope of the effective height ( h 0) of the cross section is in direct proportion to the distance from the fiber to the neutral axis. The strain of the FRP and steel rebar satisfies the equation: ɛ FRP= βɛ steel, and the value of β is equal to 1.1-1.3 according to the test results.

KENNEDY SPACE CENTER, FLA. - The Mars Exploration Rover 1 (MER-1) is seen after installation of the air bags on the outside of the lander. The airbags will inflate to cushion the landing of the spacecraft on the surface of Mars. When it stops bouncing and rolling, the airbags will deflate and retract, the petals will open to bring the lander to an upright position, and the rover will be exposed. NASA's twin Mars Exploration Rovers are designed to study the history of water on Mars. These robotic geologists are equipped with a robotic arm, a drilling tool, three spectrometers, and four pairs of cameras that allow them to have a human-like, 3D view of the terrain. Each rover could travel as far as 100 meters in one day to act as Mars scientists' eyes and hands, exploring an environment where humans can't yet go. MER-1 is scheduled to launch June 25 as MER-B aboard a Delta II rocket from Cape Canaveral Air Force Station.

NASA Image and Video Library

2003-05-10

KENNEDY SPACE CENTER, FLA. - The Mars Exploration Rover 1 (MER-1) is seen after installation of the air bags on the outside of the lander. The airbags will inflate to cushion the landing of the spacecraft on the surface of Mars. When it stops bouncing and rolling, the airbags will deflate and retract, the petals will open to bring the lander to an upright position, and the rover will be exposed. NASA's twin Mars Exploration Rovers are designed to study the history of water on Mars. These robotic geologists are equipped with a robotic arm, a drilling tool, three spectrometers, and four pairs of cameras that allow them to have a human-like, 3D view of the terrain. Each rover could travel as far as 100 meters in one day to act as Mars scientists' eyes and hands, exploring an environment where humans can't yet go. MER-1 is scheduled to launch June 25 as MER-B aboard a Delta II rocket from Cape Canaveral Air Force Station.

Glatz Prototype Seat Impact Testing

DTIC Science & Technology

2013-07-03

airbag restraint, H-60A/L, crashworthiness, crashworthy, helicopter, rotorcraft, occupant restraint 16. SECURITY CLASSIFICATION OF: 17...data for Cell C, incorporating the H-60 Comp data, the new Glatz prototype data, and data from the airbag restraint program with a modified H-60A/L seat...1711 GLATZ VDT6290 Glatz 24.37 40.52 YES 922 42.40 1732 AIRBAG VDT6287 H-60A/L w/crotch strap mod 21.39* 40.56 YES 1267 21.27 1373 *Issue with

Improved fault tolerance for air bag release in automobiles

NASA Astrophysics Data System (ADS)

Yeshwanth Kumar, C. H.; Prudhvi Prasad, P.; Uday Shankar, M.; Shanmugasundaram, M.

2017-11-01

In order to increase the reliability of the airbag system in automobiles which in turn increase the safety of the automobile we require improved airbag release system, our project deals with Triple Modular Redundancy (TMR) Technique where we use either three Sensors interfaced with three Microcontrollers which given as input to the software voter which produces majority output which is feed to the air compressor for releasing airbag. This concept was being used, in this project we are increasing reliability and safety of the entire system.

The Smile Esthetic Index (SEI): A method to measure the esthetics of the smile. An intra-rater and inter-rater agreement study.

PubMed

Rotundo, Roberto; Nieri, Michele; Bonaccini, Daniele; Mori, Massimiliano; Lamberti, Elena; Massironi, Domenico; Giachetti, Luca; Franchi, Lorenzo; Venezia, Piero; Cavalcanti, Raffaele; Bondi, Elena; Farneti, Mauro; Pinchi, Vilma; Buti, Jacopo

2015-01-01

To propose a method to measure the esthetics of the smile and to report its validation by means of an intra-rater and inter-rater agreement analysis. Ten variables were chosen as determinants for the esthetics of a smile: smile line and facial midline, tooth alignment, tooth deformity, tooth dischromy, gingival dischromy, gingival recession, gingival excess, gingival scars and diastema/missing papillae. One examiner consecutively selected seventy smile pictures, which were in the frontal view. Ten examiners, with different levels of clinical experience and specialties, applied the proposed assessment method twice on the selected pictures, independently and blindly. Intraclass correlation coefficient (ICC) and Fleiss' kappa) statistics were performed to analyse the intra-rater and inter-rater agreement. Considering the cumulative assessment of the Smile Esthetic Index (SEI), the ICC value for the inter-rater agreement of the 10 examiners was 0.62 (95% CI: 0.51 to 0.72), representing a substantial agreement. Intra-rater agreement ranged from 0.86 to 0.99. Inter-rater agreement (Fleiss' kappa statistics) calculated for each variable ranged from 0.17 to 0.75. The SEI was a reproducible method, to assess the esthetic component of the smile, useful for the diagnostic phase and for setting appropriate treatment plans.

Improved inflatable landing systems for low cost planetary landers

NASA Astrophysics Data System (ADS)

Northey, Dave; Morgan, Chris

2006-10-01

Inflatable landing systems have been traditionally perceived as a cost-effective solution to the problem of landing a spacecraft on a planetary surface. To date, the systems used have all employed the approach of surrounding the lander with non-vented airbags where the lander on impact bounces a number of times until the impact energy is dissipated. However, the reliability record of such systems is not at all good. This paper examines the problems involved in the use of non-vented airbags, and how these problems have been overcome by the use of vented airbags in terrestrial systems. Using a specific case study, it is shown that even the basic passive type of venting can give significant mass reductions. It is also shown that actively controlling the venting based on the landing scenario can further enhance the performance of vented airbags.

Improved inflatable landing systems for low cost planetary landers

NASA Astrophysics Data System (ADS)

Northey, Dave; Morgan, Chris

2003-11-01

Inflatable landing systems have been traditionally perceived as a cost-effective solution to the problem of landing a spacecraft on a planetary surface. To date the systems used have all employed the approach of surrounding the lander with non-vented airbags where the lander bounces on impact a number of times until the impact energy is dissipated. However the reliability record of such systems is not at all good. This paper examines the problems involved in the use of non-vented airbags, and how these problems have been overcome by the use of vented airbags in terrestrial systems. Using a specific case study, it is shown that even the basic passive type of venting can give significant mass reductions. It is also shown that actively controlling the venting based on the landing scenario can further enhance the performance of vented airbags.

Interim Columbia and Snake rivers flow improvement measures for salmon: Final Supplemental Environmental Impact Statement (SEIS)

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

Not Available

1993-03-01

Public comments are sought on this final SEIS, which supplements the 1992 Columbia River Salmon Flow Measures Options Analysis (OA)/Environmental Impact Statement (EIS). The Corps of Engineers, in cooperation with the Bonneville Power Administration and the Bureau of Reclamation proposes five alternatives to improve flows of water in the lower Columbia-Snake rivers in 1993 and future years to assist the migration of juvenile and adult anadromous fish past eight hydropower dams. These are: (1) Without Project (no action) Alternative, (2) the 1992 Operation, (3) the 1992 Operation with Libby/Hungry Horse Sensitivity, (4) a Modified 1992 Operation with Improvements to Salmonmore » Flows from Dworshak, and (5) a Modified 1992 Operation with Upper Snake Sensitivity. Alternative 4, Modified 1992 Operations, has been identified as the preferred alternative.« less

Fe model predicting the increase in seismic resistance induced by the progressive FRP strengthening on already damaged masonry arches subjected to settlement

NASA Astrophysics Data System (ADS)

Stockdale, G.; Milani, G.

2017-11-01

In seismic regions, the retrofitting of masonry structures subjected to differential foundation settlements is of the upmost importance. This practice however poses significant challenges, most notably in the consideration of historical monuments where the integrity of the original structure must be weighted alongside public safety. Fiber reinforced polymers (FRPs), when appropriately applied, provide the potential to balance this duality of heritage preservation and modern safety. Using an advanced FE point of view, this work studies the seismic response of a progressive reinforcement strategy aimed at strengthening and controlling the failure mechanism for masonry arches that exist in a damaged state induced through a differential abutment settlement. A heterogeneous FE approach of a semi-circular block and mortar arch on continuously spreading supports is examined. In this model hinge formation is obtained by assigning a damage plasticity behavior to the mortar joints. Strategically placed FRPs, designed through the utilization of the Italian CNR recommendations for externally bonded FRP systems, are applied through the Abaqus birth and death approach and introduced to the spreading support model after settlement. Finally, the structural behavior of the reinforced and unreinforced models are examined for a seismic response.

New generation fiber reinforced polymer composites incorporating carbon nanotubes

NASA Astrophysics Data System (ADS)

Soliman, Eslam

The last five decades observed an increasing use of fiber reinforced polymer (FRP) composites as alternative construction materials for aerospace and infrastructure. The high specific strength of FRP attracted its use as non-corrosive reinforcement. However, FRP materials were characterized with a relatively low ductility and low shear strength compared with steel reinforcement. On the other hand, carbon nanotubes (CNTs) have been introduced in the last decade as a material with minimal defect that is capable of increasing the mechanical properties of polymer matrices. This dissertation reports experimental investigations on the use of multi-walled carbon nanotubes (MWCNTs) to produce a new generation of FRP composites. The experiments showed significant improvements in the flexure properties of the nanocomposite when functionalized MWCNTs were used. In addition, MWCNTs were used to produce FRP composites in order to examine static, dynamic, and creep behavior. The MWCNTs improved the off-axis tension, off-axis flexure, FRP lap shear joint responses. In addition, they reduced the creep of FRP-concrete interface, enhanced the fracture toughness, and altered the impact resistance significantly. In general, the MWCNTs are found to affect the behaviour of the FRP composites when matrix failure dominates the behaviour. The improvement in the mechanical response with the addition of low contents of MWCNTs would benefit many industrial and military applications such as strengthening structures using FRP composites, composite pipelines, aircrafts, and armoured vehicles.

Earthquake Monitoring: SeisComp3 at the Swiss National Seismic Network

NASA Astrophysics Data System (ADS)

Clinton, J. F.; Diehl, T.; Cauzzi, C.; Kaestli, P.

2011-12-01

The Swiss Seismological Service (SED) has an ongoing responsibility to improve the seismicity monitoring capability for Switzerland. This is a crucial issue for a country with low background seismicity but where a large M6+ earthquake is expected in the next decades. With over 30 stations with spacing of ~25km, the SED operates one of the densest broadband networks in the world, which is complimented by ~ 50 realtime strong motion stations. The strong motion network is expected to grow with an additional ~80 stations over the next few years. Furthermore, the backbone of the network is complemented by broadband data from surrounding countries and temporary sub-networks for local monitoring of microseismicity (e.g. at geothermal sites). The variety of seismic monitoring responsibilities as well as the anticipated densifications of our network demands highly flexible processing software. We are transitioning all software to the SeisComP3 (SC3) framework. SC3 is a fully featured automated real-time earthquake monitoring software developed by GeoForschungZentrum Potsdam in collaboration with commercial partner, gempa GmbH. It is in its core open source, and becoming a community standard software for earthquake detection and waveform processing for regional and global networks across the globe. SC3 was originally developed for regional and global rapid monitoring of potentially tsunamagenic earthquakes. In order to fulfill the requirements of a local network recording moderate seismicity, SED has tuned configurations and added several modules. In this contribution, we present our SC3 implementation strategy, focusing on the detection and identification of seismicity on different scales. We operate several parallel processing "pipelines" to detect and locate local, regional and global seismicity. Additional pipelines with lower detection thresholds can be defined to monitor seismicity within dense subnets of the network. To be consistent with existing processing

Ionic Liquid-Enhanced Solid State Electrolyte Interface (SEI) for Lithium Sulfur Batteries

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

Zheng, Jianming; Gu, Meng; Chen, Honghao

2013-05-16

Li-S battery is a complicated system with many challenges existing before its final market penetration. While most of the reported work for Li-S batteries is focused on the cathode design, we demonstrate in this work that the anode consumption accelerated by corrosive polysulfide solution also critically determines the Li-S cell performance. To validate this hypothesis, ionic liquid (IL) N-methyl-N-butylpyrrolidinium bis(trifluoromethylsulfonyl)imide (Py14TFSI) has been employed to modify the properties of SEI layer formed on Li metal surface in Li-S batteries. It is found that the IL-enhanced passivation film on the lithium anode surface exhibits much different morphology and chemical compositions, effectivelymore » protecting lithium metal from continuous attack by soluble polysulfides. Therefore, both cell impedance and the irreversible consumption of polysulfides on lithium metal are reduced. As a result, the Coulombic efficiency and the cycling stability of Li-S batteries have been greatly improved. After 120 cycles, Li-S battery cycled in the electrolyte containing IL demonstrates a high capacity retention of 94.3% at 0.1 C rate. These results unveil another important failure mechanism for Li-S batteries and shin the light on the new approaches to improve Li-S battery performances.« less

A Feasibility Study on Numerical Modeling of Large-Scale Naval Fluid-Filled Structure: Contact-Impact Problems

DTIC Science & Technology

2011-02-01

capabilities for airbags , sensors, and seatbelts have tailored the code for applications in the automotive industry. Currently the code contains...larger intervals. In certain contact scenarios where contacting parts are moving relative to each other in a rapid fashion, such as airbag deployment

The development of crashworthy rails for fiber reinforced polymer honeycomb bridge deck system.

DOT National Transportation Integrated Search

2015-07-01

Fiber reinforced polymer (FRP) honeycomb panels offer an efficient and rapid replacement to : concrete decks. The system consists of FRP honeycomb sandwich panels with adequate guardrails. Although : FRP bridge deck panels have already been designed ...

The development of crashworthy rails for fiber reinforced polymer honeycomb bridge deck system : [summary].

DOT National Transportation Integrated Search

2015-07-01

Fiber reinforced polymer (FRP) honeycomb panels offer an efficient and rapid : replacement to concrete decks. The system consists of FRP honeycomb sandwich panels : with adequate guardrails. Although FRP bridge deck panels have already been designed ...

U-Pb zircon geochronologycal investigation on the Morro dos Seis Lagos Carbonatite Complex and associated Nb deposit (Amazonas, Brazil)

NASA Astrophysics Data System (ADS)

Rossoni, Marco B.; Bastos Neto, Artur C.; Souza, Valmir S.; Marques, Juliana C.; Dantas, Elton; Botelho, Nilson F.; Giovannini, Arthur L.; Pereira, Vitor P.

2017-12-01

We present results of U-Pb dating (by MC-ICP-MS) of zircons from samples that cover all of the known lithotypes in the Seis Lagos Carbonatite Complex and associated lateritic mineralization (the Morro dos Seis Lagos Nb deposit). The host rock (gneiss) yielded an age of 1828 ± 09 Ma interpreted as the crystallization time of this unit. The altered feldspar vein in the same gneiss yielded an age of 1839 ± 29 Ma. Carbonatite samples provided 3 groups of ages. The first group comprises inherited zircons with ages compatible with the gneissic host rock: 1819 ± 10 Ma (superior intercept), 1826 ± 5 Ma (concordant age), and 1812 ± 27 Ma (superior intercept), all from the Orosirian. The second and the third group of ages are from the same carbonatite sample: the superior intercept age of 1525 ± 21 Ma (MSWD = 0.77) and the superior intercept age of 1328 ± 58 Ma (MSWD = 1.4). The mineralogical study indicates that the ∼1.3 Ga zircons have affinity with carbonatite. It is, however, a tendence rather than a well-defined result. The data allow state that the age of 1328 ± 58 Ma represents the maximum age of the carbonatite. Without the same certainty, we consider that the data suggest that this age may be the carbonatite age, whose emplacement would have been related to the evolution of the K'Mudku belt. The best age obtained in laterite samples (a superior intercept age of 1828 ± 12 Ma) is considered the age of the main source for the inherited zircons related to the gneissic host rock.

Small-scale spatial variability of sperm and sei whales in relation to oceanographic and topographic features along the Mid-Atlantic Ridge

NASA Astrophysics Data System (ADS)

Skov, H.; Gunnlaugsson, T.; Budgell, W. P.; Horne, J.; Nøttestad, L.; Olsen, E.; Søiland, H.; Víkingsson, G.; Waring, G.

2008-01-01

The 2004 Mid-Atlantic Ridge (MAR)-ECO expedition on the R.V. G.O. Sars provided the first opportunity to correlate oceanic distributions of cetaceans with synoptic acoustic (ADCP to 700 m depth, multi-beam echosounders) measurements of high-resolution, three-dimensional (3D) potential habitat (spatial scale<100 km). The identified habitat features were tested with independent observations from the Icelandic combined cetacean and redfish cruises in 2001 and 2003 using data from a 3D ocean general circulation model of the MAR region (Regional Oceans Modelling System (ROMS) model 5 km resolution). The spatial autocorrelation of sampled encounter rates of sperm Physeter macrocephalus and sei whales Balaenoptera borealis indicated scale-dependent variability in the distribution of both species. Despite the large area surveyed, the observations of both species exhibited a strong small-scale structure (range parameter 20-50 km), indicating affinities to cross-seamount or cross-frontal structures. Potential cross-seamount and cross-frontal habitat structures were derived from the acoustic transect data by analysing fine-scale gradients in the 3D flow patterns and bathymetry, including interactions between frontal and topographic parameters. PLS regression was used to determine the potential habitat drivers of sperm and sei whales, both during the G.O. Sars cruise and during the Icelandic cruises in 2001 and 2003. The selected parameters, which reflected flow gradients interacting with the steep topography, were finally applied for modelling the habitat suitability of both target species along the northern MAR using Ecological Niche Factor Analysis. The results suggest aggregations of sperm and sei whales along the MAR are primarily associated with fine-scale frontal processes interacting with the topography in the upper 100 m of the water column just north of the Sub-Polar Front (SPF) and the Charlie-Gibbs Fracture Zone (CGFZ). As moderate and high habitat suitabilities

2008 Federal Radionavigation Plan

DOT National Transportation Integrated Search

2009-01-01

The Federal Radionavigation Plan (FRP) is the official source of radionavigation policy and planning for the Federal Government. The FRP covers common-use, Federally operated radionavigation systems. This edition of the FRP combines the Federal Radio...

Chemical characterization of the oligosaccharides in Bryde's whale (Balaenoptera edeni) and Sei whale (Balaenoptera borealis lesson) milk.

PubMed

Urashima, Tadasu; Kobayashi, Mami; Asakuma, Sadaki; Uemura, Yusuke; Arai, Ikichi; Fukuda, Kenji; Saito, Tadao; Mogoe, Toshihiro; Ishikawa, Hajime; Fukui, Yutaka

2007-02-01

Samples of milk from a Bryde's whale and a Sei whale contained 2.7 g/100 mL and 1.7 g/100 mL of hexose, respectively. Both contained lactose as the dominant saccharide along with small amounts of Neu5Ac(alpha2-3)Gal(beta1-4)Glc (3'-N-acetylneuraminyllactose), Neu5Ac(alpha2-6)Gal(beta1-4)Glc (6'-N-acetylneuraminyllactose) and Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)Glc (LST c). The dominance of lactose in the carbohydrate of these milks is similar to that of Minke whale milk and bottlenose dolphin colostrum, but the oligosaccharide patterns are different from those of these two species, illustrating the heterogeneity of milk oligosaccharides among the Cetacea.

New Submerged-Robot Control Optical Fiber Cable With Small-Diameter, High-Strength Frp Covered Optical Fiber

NASA Astrophysics Data System (ADS)

Fuse, K.; Shirasaka, Y.; Yanagawa, H.

1984-10-01

Of natural resources on the earth, the utilization of the oceans has the oldest history, and the development of them has been delayed most. However, hot expectation is being placed on the development of the oceans. The element that obstructs the acceleration of such development is the sea itself. From a technical viewpoint, the means to explore the oceans have not been developed sufficiently, and equipment such as special large vehicles and ships has been bulky, requiring a very large sum of money to prepare them. These have been part of the reasons why the development of the oceans has been delayed. For this reason, a large number of exploratory systems will be studied as the ocean development becomes active in the near future. A single optical fiber cable has been considered as a cable for control of an ocean exploratory robot, which weighs approximately 30 to 40 kg at most in air requiring no power feeding to the drive section inside the vehicle and running by self on a built-in battery, as well as for data transfer. This cable is believed most suitable in terms of high speed mobility, transmission characteristics, and system cost. The mode (system) of pay off of the cable paid off by the ship loading such a cable becomes very important in the design of optical fiber cables for control of ocean exploratory robots. This paper introduces a new FRP covered optical fiber cable developed as an optical fiber cable for control of ocean exploratory robots with a small diameter and rotating motion. This cable is considered most suitable for the pay off-system which is simple and offers the highest space utility. The paper describes a basic study made prior to an actual performance test in the sea, as well as its design and characteristics.

Development of Meteorological Towers Using Advanced Composite Materials

NASA Astrophysics Data System (ADS)

Alshurafa, Sami A.

The research program involved both numerical and experimental work. The numerical analysis was conducted to simulate the static and dynamic behaviour of the 81 m meteorological FRP guyed tower under wind and ice loading. The FRP tower consisted of 16 segments each made of 3 cells connected together to form an equilateral triangle having equal sides of 450 mm. The segments were interconnected using internal sleeves. Various non-linear finite element models were developed to study a number of design parameters for the 81 m FRP tower such as, different laminates containing a variety of stacking sequences of laminate orientations with various thicknesses, different cable diameters, and appropriate guy cable spacing levels. The effect of pre-stressing the guy cables up to 10 % of their breaking strength was investigated. The effect of fibre volume fraction on the design of the FRP tower was also examined. Furthermore, an 8.6 m FRP tower segment was designed using the finite element analysis and subject to the same loading conditions experienced by the bottom section of the 81 m FRP tower. A modal analysis was carried out for both the 8.6 m FRP tower segment with and without a mass on the top as well as for the 81 m FRP guyed tower to evaluate the vibration performance of these towers. The experimental work involved extensive material testing to define the material properties for use in the analysis of the 81 m FRP tower. It also involved the design and fabrication of a special collapsible mandrel for fabricating the FRP cells for the 8.6 m tower segment. The 8.6 m tower was tested horizontally under static lateral loading to 80 % of its estimated failure load using a "whiffle tree" arrangement, in order to simulate a uniformly distributed wind loading. Later, the same FRP tower was erected in a vertical position and was tested with and without a mass on top under dynamic loading to obtain the natural frequencies. Lastly, a comparative study was conducted between two 81

A Hybrid Computing Testbed for Mobile Threat Detection and Enhanced Research and Education in Information

DTIC Science & Technology

2014-11-20

techniques to defend against stealthy malware, i.e., rootkits. For example, we have been developing new virtualization-based security service called AirBag ...for mobile devices. AirBag is a virtualization-based system that enables dynamic switching of (guest) Android im- ages in one VM, with one image

An approach for finding long period elliptical orbits for precursor SEI missions

NASA Technical Reports Server (NTRS)

Fraietta, Michael F.; Bond, Victor R.

1993-01-01

Precursors for Solar System Exploration Initiative (SEI) missions may require long period elliptical orbits about a planet. These orbits will typically have periods on the order of tens to hundreds of days. Some potential uses for these orbits may include the following: studying the effects of galactic cosmic radiation, parking orbits for engineering and operational test of systems, and ferrying orbits between libration points and low altitude orbits. This report presents an approach that can be used to find these orbits. The approach consists of three major steps. First, it uses a restricted three-body targeting algorithm to determine the initial conditions which satisfy certain desired final conditions in a system of two massive primaries. Then the initial conditions are transformed to an inertial coordinate system for use by a special perturbation method. Finally, using the special perturbation method, other perturbations (e.g., sun third body and solar radiation pressure) can be easily incorporated to determine their effects on the nominal trajectory. An algorithm potentially suitable for on-board guidance will also be discussed. This algorithm uses an analytic method relying on Chebyshev polynomials to compute the desired position and velocity of the satellite as a function of time. Together with navigation updates, this algorithm can be implemented to predict the size and timing for AV corrections.

The effect of air bags on pregnancy outcomes in Washington State: 2002-2005.

PubMed

Schiff, Melissa A; Mack, Christopher D; Kaufman, Robert P; Holt, Victoria L; Grossman, David C

2010-01-01

To estimate whether air-bag deployment is associated with an increased risk of adverse pregnancy outcomes. We performed a retrospective cohort study to assess the effect of air-bag availability and air-bag deployment on the risk of adverse pregnancy outcomes among pregnant, front-seat occupants in motor vehicle crashes in Washington State. Pregnant women involved in motor vehicle crashes were identified by linking birth and fetal death certificate data with Washington State Patrol crash data, which reported air-bag availability and deployment. We calculated relative risks (RRs) of adverse maternal and perinatal outcomes and 95% confidence intervals (CIs) using Poisson regression, adjusted for maternal age, seatbelt use, and vehicle model year. We found no increased risk of adverse maternal or perinatal pregnancy outcomes among occupants of air-bag-equipped vehicles in all collisions (n=2,207) compared with those in vehicles without air bags (n=1,141). Among crashes in which air-bag deployment would be likely, we found a nonsignificant 70% increased risk of preterm labor (RR 1.7, 95% CI 0.9-3.2) and a nonsignificant threefold increased risk (RR 3.1, 95% CI 0.4-22.1) of fetal death among occupants in vehicles with air-bag deployment compared with occupants in vehicles without air bags, although fetal death results were limited by small numbers (2/198 [1.0%] in pregnant women whose air bags deployed; 2/622 [0.3%] in pregnant women whose air bags did not deploy). Our findings provide clinicians with evidence to advise women that air bags do not seem to elevate risk of most potential adverse outcomes during pregnancy. II.

Wide-Angle Refraction Tomographic Inversion of Mid Cayman Spreading Center and its Oceanic Core Complex, CaySEIS Experiment

NASA Astrophysics Data System (ADS)

Harding, J.; Van Avendonk, H. J.; Hayman, N. W.; Grevemeyer, I.; Peirce, C.; Dannowski, A.; Papenberg, C. A.

2015-12-01

The CaySEIS experiment, conducted in April 2015, is a multi-national collaborative seismic study of the Mid Cayman Spreading Center (MCSC), an ultra-slow spreading center [15 mm/yr fr] in the Caribbean Sea. Ultra-slow spreading centers are thought to have very thin crust and a paucity of magmatism due to cooler mantle conditions. However, the suggestion that gabbro-cored oceanic core complexes (OCCs), volcanic deposits, and multiple layers of hydrothermal vents are widespread in the MCSC and other ultra-slow spreading centers has led to questions about the relationship between seafloor spreading rates and magmatism. To investigate this further, we conducted the CaySEIS experiment, with five wide-angle seismic refraction lines parallel and perpendicular to the neovolcanic zone. This analysis is based on two east-west oriented 100-km-long seismic refraction lines, which were each occupied by 18 ocean bottom seismometers. Line 2 lies across the central MCSC and an OCC called Mt. Dent. Line 3 crosses the northern end of the MCSC near the Oriente Transform Zone. With the wide-angle OBS data we can image the seismic velocity structure of Mt. Dent and distinguish between two models of OCCs - either Mt. Dent is composed of mostly gabbro with peridotite lenses identified by a low velocity gradient, or it is composed of mostly peridotite with gabbroic bodies identified by a constant velocity gradient. The crustal structure of both lines gives more insight into the asymmetry of the MCSC and the style of seafloor spreading to the east vs. the west. The 2-D velocity models reveal Mt. Dent has thick crust of 8 km with a low velocity gradient, supporting the magmatic gabbroic origin of OCCs. The surrounding crust to the west of the MCSC is highly variable, with areas of very thin crust. The crust to the east of the MCSC has an approximately constant thickness of 4 km. The development of OCCs may contribute to the crustal heterogeneity of ultra-slow spreading centers.

Strategic sensor locations of FPR bridge decks

NASA Astrophysics Data System (ADS)

Wu, Hwai-Chung; Warnemuende, Kraig; Yan, An; Mu, Bin

2003-07-01

Advanced fiber-reinforced polymer composite (FRP) has been increasingly used in bridge deck to replace concrete or steel. A FRP bridge deck can be designed to meet AASHTO HS-25 load requirements. FRP decks have many advantages over the conventional reinforced concrete or steel decks owing to their lightweight, high strength and corrosion resistance. However, such new deck system requires extensive monitoring to ensure its designed performance before its widespread acceptance by the bridge community. For inspection and evaluation purpose, a proper monitoring system consisting of various kinds of sensors installed in the FRP deck is critical. This paper provides a framework for designing an efficient monitoring system. The strategic sensor locations are identified based on the stress analysis of the FRP deck.

Laboratory Reconstructions of Real World Frontal Crash Configurations using the Hybrid III and THOR Dummies and PMHS.

PubMed

Petitjean, Audrey; Lebarbe, Matthieu; Potier, Pascal; Trosseille, Xavier; Lassau, Jean-Pierre

2002-11-01

Load-limiting belt restraints have been present in French cars since 1995. An accident study showed the greater effectiveness in thorax injury prevention using a 4 kN load limiter belt with an airbag than using a 6 kN load limiter belt without airbag. The criteria for thoracic tolerance used in regulatory testing is the sternal deflection for all restraint types, belt and/or airbag restraint. This criterion does not assess the effectiveness of the restraint 4 kN load limiter belt with airbag observed in accidentology. To improve the understanding of thoracic tolerance, frontal sled crashes were performed using the Hybrid III and THOR dummies and PMHS. The sled configuration and the deceleration law correspond to those observed in the accident study. Restraint conditions evaluated are the 6 kN load-limiting belt and the 4 kN load-limiting belt with an airbag. Loads between the occupant and the sled environment were recorded. Various measurements (including thoracic deflections and head, thorax and pelvis accelerations and angular velocities on the dummies) characterize the dummy and PMHS behavior. PMHS anthropometry and injuries were noted. This study presents the test methodology and the results used to evaluate dummy ability to discriminate both restraint types and dummy measurement ability to be representative of thoracic injury risk for all restraint types. The injury results of the PMHS tests showed the same tendency as the accident study. Some of the criteria proposed in the literature did not show a better protection of the 4 kN load limiter belt with airbag restraint, in particular thoracic deflection maxima for both dummies. The four thoracic deflections measured on the THOR and Hybrid III dummies may allow more accurate analysis of the loading pattern and therefore of injury risk.

Secreted Frizzled-related protein 2 as a target in antifibrotic therapeutic intervention.

PubMed

Mastri, Michalis; Shah, Zaeem; Hsieh, Karin; Wang, Xiaowen; Wooldridge, Bailey; Martin, Sean; Suzuki, Gen; Lee, Techung

2014-03-15

Progressive fibrosis is a pathological hallmark of many chronic diseases responsible for organ failure. Although there is currently no therapy on the market that specifically targets fibrosis, the dynamic fibrogenic process is known to be regulated by multiple soluble mediators that may be therapeutically intervened. The failing hamster heart exhibits marked fibrosis and increased expression of secreted Frizzled-related protein 2 (sFRP2) amenable to reversal by mesenchymal stem cell (MSC) therapy. Given the previous demonstration that sFRP2-null mice subjected to myocardial infarction exhibited reduced fibrosis and improved function, we tested whether antibody-based sFRP2 blockade might counteract the fibrogenic pathway and repair cardiac injury. Cardiomyopathic hamsters were injected intraperitoneally twice a week each with 20 μg of sFRP2 antibody. Echocardiography, histology, and biochemical analyses were performed after 1 mo. sFRP2 antibody increased left ventricular ejection fraction from 40 ± 1.2 to 49 ± 6.5%, whereas saline and IgG control exhibited a further decline to 37 ± 0.9 and 31 ± 3.2%, respectively. Functional improvement is associated with a ∼ 50% reduction in myocardial fibrosis, ∼ 65% decrease in apoptosis, and ∼ 75% increase in wall thickness. Consistent with attenuated fibrosis, both MSC therapy and sFRP2 antibody administration significantly increased the activity of myocardial matrix metalloproteinase-2. Gene expression analysis of the hamster heart and cultured fibroblasts identified Axin2 as a downstream target, the expression of which was activated by sFRP2 but inhibited by therapeutic intervention. sFRP2 blockade also increased myocardial levels of VEGF and hepatocyte growth factor (HGF) along with increased angiogenesis. These findings highlight the pathogenic effect of dysregulated sFRP2, which may be specifically targeted for antifibrotic therapy.

Tensile and fatigue behavior of polymer composites reinforced with superelastic SMA strands

NASA Astrophysics Data System (ADS)

Daghash, Sherif M.; Ozbulut, Osman E.

2018-06-01

This study explores the use of superelastic shape memory alloy (SMA) strands, which consist of seven individual small-diameter wires, in an epoxy matrix and characterizes the tensile and fatigue responses of the developed SMA/epoxy composites. Using a vacuum assisted hand lay-up technique, twelve SMA fiber reinforced polymer (FRP) specimens were fabricated. The developed SMA-FRP composites had a fiber volume ratio of 50%. Tensile response of SMA-FRP specimens were characterized under both monotonic loading and increasing amplitude loading and unloading cycles. The degradation in superelastic properties of the developed SMA-FRP composites during fatigue loading at different strain amplitudes was investigated. The effect of loading rate on the fatigue response of SMA-FRP composites was also explored. In addition, fractured specimens were examined using the scanning electron microscopy (SEM) technique to study the failure mechanisms of the tested specimens. A good interfacial bonding between the SMA strands and epoxy matrix was observed. The developed SMA-FRP composites exhibited good superelastic behavior at different strain amplitudes up to at least 800 cycle after which significant degradation occurred.

Comparative effects of pyrolytic products of fiber reinforced plastic and wood shavings on the respiratory variables in mice.

PubMed

Kumar, Pravin; Deb, Utsab; Gautam, Anshoo; Vijayaraghavan, R; Ratna, Debdatta; Chakraborty, B C

2010-08-01

Comparative inhalation toxicity studies of pyrolytic products (smoke) from synthetic polymer, fiberglass reinforced plastic (FRP) and teak wood shavings were carried out in male Swiss albino mice. The breathing pattern and the respiratory variables were monitored using a computer program that recognizes the modifications of the respiratory pattern. Exposure to the smoke from both the polymers caused a concentration dependent decrease in normal breathing and an increase in sensory irritation measure. The acute lethal concentration 50 values for a 15 min static inhalation exposure to the smoke from FRP and teak wood shavings were found to be > 200.00 and 62.99 g/m(3), respectively. Hence the inhalation toxicity of smoke from FRP sample on a mass basis is approximately one-third that of the smoke from teak wood. The concentration of smoke causing 50% respiratory depression of the exposed animals were found to be 6.877 and 0.106 g/m(3) for FRP and teak wood samples, respectively. Thus the sensory irritancy of the smoke from FRP sample is approximately 65 times lesser than the smoke from teak wood. The higher sensory irritancy potential of wood smoke as compared to FRP smoke may be caused by a greater number of submicron particles (size range of 2 micron and less) and greater percentage of gases present in wood smoke as compared to FRP smoke. Thus in case of accidental fires, synthetic polymers like FRP may be a safer choice for structural parts and interiors than the natural wood.

Complete amino acid sequence of the myoglobin from the Pacific sei whale, Balaenoptera borealis.

PubMed

Jones, B N; Rothgeb, T M; England, R D; Gurd, F R

1979-04-25

The complete amino acid sequence of the major component myoglobin from Pacific sei whale, Balaenoptera borealis, was determined by specific cleavage of the protein to obtain large peptides which are readily degraded by the automatic sequencer. The acetimidated apomyoglobin was selectively cleaved at its two methionyl residues with cyanogen bromide and at its three arginyl residues by trypsin. From the sequence analysis of four of these peptides and the apomyoglobin, over 75% of the covalent structure of the protein was obtained. The remainder of the primary structure was determined by the sequence analysis of peptides that resulted from further digestion of the amino-terminal and central cyanogen bromide fragments. The amino-terminal fragment was specifically cleaved at its two tryptophanyl residues with N-chlorosuccinimide and the central cyanogen bromide fragment was cleaved at its glutamyl residues with staphylococcal protease and at its single tyrosyl residue with N-bromosuccinimide. The primary structure of this myoglobin proved identical with that from the gray whale but differs from that of the finback whale at four positions, from that of the minke whale at three positions and from the myoglobin of the humpback whale at one position. The above sequence identities and differences reflect the close taxonomic relationship of these five species of Cetacea.

Incremental dynamic analysis of concrete moment resisting frames reinforced with shape memory composite bars

NASA Astrophysics Data System (ADS)

Zafar, Adeel; Andrawes, Bassem

2012-02-01

Fiber reinforced polymer (FRP) reinforcing bars have been used in concrete structures as an alternative to conventional steel reinforcement, in order to overcome corrosion problems. However, due to the linear behavior of the commonly used reinforcing fibers, they are not considered in structures which require ductility and damping characteristics. The use of superelastic shape memory alloy (SMA) fibers with their nonlinear elastic behavior as reinforcement in the composite could potentially provide a solution for this problem. Small diameter SMA wires are coupled with polymer matrix to produce SMA-FRP composite, which is sought in this research as reinforcing bars. SMA-FRP bars are sought in this study to enhance the seismic performance of reinforced concrete (RC) moment resisting frames (MRFs) in terms of reducing their residual inter-story drifts while still maintaining the elastic characteristics associated with conventional FRP. Three story one bay and six story two bay RC MRF prototype structures are designed with steel, SMA-FRP and glass-FRP reinforcement. The incremental dynamic analysis technique is used to investigate the behaviors of the two frames with the three different reinforcement types under a suite of ground motion records. It is found that the frames with SMA-FRP composite reinforcement exhibit higher performance levels including lower residual inter-story drifts, high energy dissipation and thus lower damage, which are important for structures in highly seismic zones.

Stiffness and strength of fiber reinforced polymer composite bridge deck systems

NASA Astrophysics Data System (ADS)

Zhou, Aixi

This research investigates two principal characteristics that are of primary importance in Fiber Reinforced Polymer (FRP) bridge deck applications: STIFFNESS and STRENGTH. The research was undertaken by investigating the stiffness and strength characteristics of the multi-cellular FRP bridge deck systems consisting of pultruded FRP shapes. A systematic analysis procedure was developed for the stiffness analysis of multi-cellular FRP deck systems. This procedure uses the Method of Elastic Equivalence to model the cellular deck as an equivalent orthotropic plate. The procedure provides a practical method to predict the equivalent orthotropic plate properties of cellular FRP decks. Analytical solutions for the bending analysis of single span decks were developed using classical laminated plate theory. The analysis procedures can be extended to analyze continuous FRP decks. It can also be further developed using higher order plate theories. Several failure modes of the cellular FRP deck systems were recorded and analyzed through laboratory and field tests and Finite Element Analysis (FEA). Two schemes of loading patches were used in the laboratory test: a steel patch made according to the ASSHTO's bridge testing specifications; and a tire patch made from a real truck tire reinforced with silicon rubber. The tire patch was specially designed to simulate service loading conditions by modifying real contact loading from a tire. Our research shows that the effects of the stiffness and contact conditions of loading patches are significant in the stiffness and strength testing of FRP decks. Due to the localization of load, a simulated tire patch yields larger deflection than the steel patch under the same loading level. The tire patch produces significantly different failure compared to the steel patch: a local bending mode with less damage for the tire patch; and a local punching-shear mode for the steel patch. A deck failure function method is proposed for predicting the

Penetrating Neck Trauma: An Unusual Case Presentation and Review of the Literature.

PubMed

McCrary, Hilary C; Nielsen, Tyson J; Goldstein, Stephen A

2016-08-01

The aim of this report is to describe a case of a retained projectile metal object to the neck that occurred after airbag deployment during a motor vehicle accident. Case report with literature review. After a motor vehicle accident on the interstate, a 19-year-old man presents to the emergency department for several open extremity fractures, a neck laceration, and a C1 lateral mass fracture. The trauma surgery team repaired the neck laceration with no further evidence of injury. Several weeks later on follow-up, the patient presents with dysphagia and pain when turning his head to the right. A repeat computed tomography angiography (CTA) scan revealed a metallic foreign body in the left posterior pharyngeal, prevertebral soft tissues, which was subsequently removed during exploratory surgery 2 months after his initial accident. This is the first report, to our knowledge, of a projectile metal object to the neck that may be related to airbag deployment. The car involved in this accident was under recall for airbags that were associated with projectile objects, which warrants further investigation into the possible risks of such airbags. © The Author(s) 2016.

Off the Charts

NASA Technical Reports Server (NTRS)

Muirhead, Brian K.

2003-01-01

NASA basically looked at the two options and said, "Well, propulsion...that's the old way of doing business. You guys will never get this job done if you do it that way. It's too expensive." And so we said, "Okay, let's go make this airbag thing work." The airbags idea was clearly eccentric. Off the charts. When you think of an airbag, you think of the automobile design, about twice the size of a pillow, which took many years to develop. But what we needed would have to be about 19 feet in diameter, designed to tolerate a head-on collision with a very rocky Mars surface at 60 miles per hour or more. And not just once, but multiple times, as it bounced and rolled to a stop. The only thing in common between our design and an automobile airbag was the name. Another very eccentric aspect of this was the idea of using fabrics in outer space. We were used to dealing in aluminum and titanium, but is needed to be the stuff of bulletproof vests...advanced polymer cloth. We'd worked with software in space, but not 'softgoods.'

Influence of Steering Control Devices Mounted in Cars for the Disabled on Passive Safety

NASA Astrophysics Data System (ADS)

Masiá, J.; Eixerés, B.; Dols, J. F.; Colomina, F. J.

2009-11-01

The purpose of this research is to analyze the influence of steering control devices for disabled people on passive safety. It is based on the advances made in the modelling and simulation of the driver position and in the suit verification test. The influence of these devices is studied through airbag deployment and/or its influence on driver safety. We characterize the different adaptations that are used in adapted cars that can be found mounted in vehicles in order to generating models that are verified by experimental test. A three dimensional design software package was used to develop the model. The simulations were generated using a dynamic simulation program employing LSDYNA finite elements. This program plots the geometry and assigns materials. The airbag is shaped, meshed and folded just as it is mounted in current vehicles. The thermodynamic model of expansion of gases is assigned and the contact interfaces are defined. Static tests were carried out on deployment of the airbag to contrast with and to validate the computational models and to measure the behaviour of the airbag when there are steering adaptations mounted in the vehicle.

Dropping in on Mars

NASA Technical Reports Server (NTRS)

Rivellini, Tommaso P.

2003-01-01

Here I was: 26 years old, I had never worked on a flight project before, and all eyes were on me. Every time I walked by the Pathfinder project office, Tony Spear, the project manager, would throw his arm around me and announce, 'Hey everybody, the whole mission is riding on this guy right here.' Our task was to design and build airbags for Pathfinder s landing on Mars - an approach that had never been used on any mission. Airbags may seem like a simple, low-tech product, but it was eye-opening to discover just how little we knew about them. We knew that the only way to find out what we needed to learn was to build prototypes and test them. We just didn t know how ignorant we were going to be. Airbags seemed like a crazy idea to a lot of people. Nobody ever said that, mind you, but there seemed to be a widespread feeling that the airbags weren t going to work. 'We ll let you guys go off and fool around until you fall flat on your faces.' That was the unspoken message I received day after day.

Development of Dietary Polyphenol Preparations for Treating Veterans with Gulf War Illness

DTIC Science & Technology

2015-10-01

chronic fatigue. We hypothesized that dietary supplementation with a Flavonoid- Rich Preparation (FRP), a combination of Concord Grape Juice (CGJ...We propose to test the feasibility of dietary supplementation with FRP in Veterans with GWI, and to gather evidence supporting the efficacy of FRP...fatigue and preserve against cognitive functions. Based on this, our overall goal is to test the potential efficacy of dietary supplementation with a

Age-related increase in Wnt inhibitor causes a senescence-like phenotype in human cardiac stem cells

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

Nakamura, Tamami; Hosoyama, Tohru; Regenerative Medicine Institute, Yamaguchi University Graduate School of Medicine

Aging of cardiac stem/progenitor cells (CSCs) impairs heart regeneration and leads to unsatisfactory outcomes of cell-based therapies. As the precise mechanisms underlying CSC aging remain unclear, the use of therapeutic strategies for elderly patients with heart failure is severely delayed. In this study, we used human cardiosphere-derived cells (CDCs), a subtype of CSC found in the postnatal heart, to identify secreted factor(s) associated with CSC aging. Human CDCs were isolated from heart failure patients of various ages (2–83 years old). Gene expression of key soluble factors was compared between CDCs derived from young and elderly patients. Among these factors, SFRP1,more » a gene encoding a Wnt antagonist, was significantly up-regulated in CDCs from elderly patients (≥65 years old). sFRP1 levels was increased significantly also in CDCs, whose senescent phenotype was induced by anti-cancer drug treatment. These results suggest the participation of sFRP1 in CSC aging. We show that the administration of recombinant sFRP1 induced cellular senescence in CDCs derived from young patients, as indicated by increased levels of markers such as p16, and a senescence-associated secretory phenotype. In addition, co-administration of recombinant sFRP1 could abrogate the accelerated CDC proliferation induced by Wnt3A. Taken together, our results suggest that canonical Wnt signaling and its antagonist, sFRP1, regulate proliferation of human CSCs. Furthermore, excess sFRP1 in elderly patients causes CSC aging. - Highlights: • Wnt signaling regulates proliferation of human cardiac stem cells. • Expression of sFRP1, which is a Wnt antagonist, is up-regulated in elderly patients with heart failure. • Expression of sFRP1 is increased in anti-cancer drug-induced senescent human cardiac stem cells. • sFRP1 causes cellular senescence of young patients-derived cardiac stem cells.« less

Environmental stress-corrosion cracking of fiberglass: lessons learned from failures in the chemical industry.

PubMed

Myers, T J; Kytömaa, H K; Smith, T R

2007-04-11

Fiberglass reinforced plastic (FRP) composite materials are often used to construct tanks, piping, scrubbers, beams, grating, and other components for use in corrosive environments. While FRP typically offers superior and cost effective corrosion resistance relative to other construction materials, the glass fibers traditionally used to provide the structural strength of the FRP can be susceptible to attack by the corrosive environment. The structural integrity of traditional FRP components in corrosive environments is usually dependent on the integrity of a corrosion-resistant barrier, such as a resin-rich layer containing corrosion resistant glass fibers. Without adequate protection, FRP components can fail under loads well below their design by an environmental stress-corrosion cracking (ESCC) mechanism when simultaneously exposed to mechanical stress and a corrosive chemical environment. Failure of these components can result in significant releases of hazardous substances into plants and the environment. In this paper, we present two case studies where fiberglass components failed due to ESCC at small chemical manufacturing facilities. As is often typical, the small chemical manufacturing facilities relied largely on FRP component suppliers to determine materials appropriate for the specific process environment and to repair damaged in-service components. We discuss the lessons learned from these incidents and precautions companies should take when interfacing with suppliers and other parties during the specification, design, construction, and repair of FRP components in order to prevent similar failures and chemical releases from occurring in the future.

Surface discharge related properties of fiberglass reinforced plastic insulator for use in neutral beam injector of JT-60U.

PubMed

Yamano, Y; Takahashi, M; Kobayashi, S; Hanada, M; Ikeda, Y

2008-02-01

Neutral beam injection (NBI) used for JT-60U is required to generate negative ions of 500 keV energies. To produce such high-energy ions, three-stage electrostatic accelerators consisting of three insulator rings made of fiberglass reinforced plastic (FRP) are applied. The surface discharges along FRP insulators are one of the most serious problems in the development of NBI. To increase the hold-off voltage against surface flashover events, it is necessary to investigate the FRP insulator properties related to surface discharges in vacuum. This paper describes surface flashover characteristics for FRP and alumina samples under vacuum condition. The results show that the fold-off voltages for FRP samples are inferior to those of alumina ceramics. In addition, measurement results of surface resistivity and volume resistivity under vacuum and atmospheric conditions, secondary electron emission characteristics, and cathodoluminescence under some keV electron beam irradiation are also reported. These are important parameters to analyze surface discharge of insulators in vacuum.

Surface discharge related properties of fiberglass reinforced plastic insulator for use in neutral beam injector of JT-60Ua)

NASA Astrophysics Data System (ADS)

Yamano, Y.; Takahashi, M.; Kobayashi, S.; Hanada, M.; Ikeda, Y.

2008-02-01

Neutral beam injection (NBI) used for JT-60U is required to generate negative ions of 500keV energies. To produce such high-energy ions, three-stage electrostatic accelerators consisting of three insulator rings made of fiberglass reinforced plastic (FRP) are applied. The surface discharges along FRP insulators are one of the most serious problems in the development of NBI. To increase the hold-off voltage against surface flashover events, it is necessary to investigate the FRP insulator properties related to surface discharges in vacuum. This paper describes surface flashover characteristics for FRP and alumina samples under vacuum condition. The results show that the fold-off voltages for FRP samples are inferior to those of alumina ceramics. In addition, measurement results of surface resistivity and volume resistivity under vacuum and atmospheric conditions, secondary electron emission characteristics, and cathodoluminescence under some keV electron beam irradiation are also reported. These are important parameters to analyze surface discharge of insulators in vacuum.

Development of Dietary Polyphenol Preparations for Treating Veterans with Gulf War Illness

DTIC Science & Technology

2016-10-01

chronic fatigue. We hypothesized that dietary supplementation with a Flavonoid Rich Preparation (FRP), a combination of Concord Grape Juice (CGJ) and...We propose to test the feasibility of dietary supplementation with FRP in Veterans with GWI, and to gather evidence supporting the efficacy of FRP in...fatigue and preserve against cognitive functions. Based on this, our overall goal is to test the potential efficacy of dietary supplementation with a

[Air bags and eye injuries: chemical burns and major traumatic ocular lesions--a case study].

PubMed

Bendeddouche, K; Assaf, E; Emadisson, H; Forestier, F; Salvanet-Bouccara, A

2003-10-01

The authors report a case of bilateral eye lesions with extended visual sequelae after the inflation of a driver's airbag during a head-on collision. The superficial facial lesions were accompanied by bilateral eye lesions, reaching both the anterior and posterior segments. Bilateral periorbital palpebral hematomas; voluminous bipalpebral edema combined with severe -conjunctival edema, corneal erosions, and edema; bilateral hyphema; pupillary changes with multiple iris sphincter breaks and weak pupillary light reflex only on the right eye; retrocession of the iridocorneal angle; and on fundus examination both retinas had posterior and peripheral hemorrhages and Berlin retinal edema. Five years after the trauma and 4 years after posttraumatic surgery for cataract that had progressively appeared on the left eye, the visual acuity is 25/20 in both eyes notwithstanding a small paracentral scotoma related to a break in the Bruch membrane. A review of the literature shows several types of ophthalmological lesions related to the airbag mechanism, which after combustion of an alkaline powder inflates at a very high speed, resulting in a risk of corneal-conjunctive-palpebral alkaline burns added to an eye contusion, which may be responsible for severe lesions. The American studies distinguish three factors affecting the seriousness of these airbag accidents: (a) wearing glasses, (b) position and size of the driver, and (c) inflation force of the airbag. Wearing a seatbelt is mandatory to minimize the violence of the oculofacial impact. After facial trauma from an airbag, an ophthalmological examination is necessary to assess of the chemical burns of the tissues exposed to the alkaline powder and possible major ocular lesions.

Global Characterization of Biomass-Burning Patterns using Satellite Measurements of Fire Radiative Energy

NASA Technical Reports Server (NTRS)

Ichoku, Charles; Giglio, Louis; Wooster, Martin J.; Remer, Lorraine A.

2008-01-01

Remote sensing is the most practical means of measuring energy release from large open-air biomass burning. Satellite measurement of fire radiative energy (FRE) release rate or power (FRP) enables distinction between fires of different strengths. Based on a 1-km resolution fire data acquired globally by the MODerate-resolution Imaging Spectro-radiometer (MODIS) sensor aboard the Terra and Aqua satellites from 2000 to 2006, instanteaneous FRP values ranged between 0.02 MW and 1866 MW, with global daily means ranging between 20 and 40 MW. Regionally, at the Aqua-MODIS afternoon overpass, the mean FRP values for Alaska, Western US, Western Australia, Quebec and the rest of Canada are significantly higher than these global means, with Quebec having the overall highest value of 85 MW. Analysis of regional mean FRP per unit area of land (FRP flux) shows that a peak fire season in certain regions, fires can be responsible for up to 0.2 W/m(sup 2) at peak time of day. Zambia has the highest regional monthly mean FRP flux of approximately 0.045 W/m(sup 2) at peak time of day and season, while the Middle East has the lowest value of approximately 0.0005 W/m(sup 2). A simple scheme based on FRP has been devised to classify fires into five categories, to facilitate fire rating by strength, similar to earthquakes and hurricanes. The scheme uses MODIS measurements of FRP at 1-km resolution as follows: catagory 1 (less than 100 MW), category 2 (100 to less than 500 MW), category 3 (500 to less than 1000 MW), category 4 (1000 to less than 1500 MW), catagory 5 (greater than or equal to 1500 MW). In most regions of the world, over 90% of fires fall into category 1, while only less than 1% fall into each of categories 3 to 5, although these proportions may differ significantly from day to day and by season. The frequency of occurence of the larger fires is region specific, and could not be explained by ecosystem type alone. Time-series analysis of the propertions of higher category

Characterization of two types of osteoclasts from human peripheral blood monocytes

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

Yuasa, Kimitaka; Mori, Kouki; Ishikawa, Hitoshi

2007-05-04

The two osteoclastogenesis pathways, receptor activator nuclear factor (NF)-{kappa}B ligand (RANKL)-mediated and fusion regulatory protein-1 (FRP-1)-mediated osteoclastogenesis, have recently been reported. There were significant differences in differentiation and activation mechanisms between the two pathways. When monocytes were cultured with FRP-1 without adding M-CSF, essential for the RANKL system, TRAP-positive polykaryocyte formation occurred. FRP-1-mediated osteoclasts formed larger pits on mineralized calcium phosphate plates than RANKL+M-CSF-mediated osteoclasts did. Lacunae on dentin surfaces induced by FRP-1-mediated osteoclasts were inclined to be single and isolated. However, osteoclasts induced by RANKL+M-CSF made many connected pits on dentin surfaces as if they crawled on there. Interestingly,more » FRP-1 osteoclastogenesis was enhanced by M-CSF/IL-1{alpha}, while chemotactic behavior to the dentin slices was not effected. There were differences in pH and concentration of HCO3- at culture endpoint and in adherent feature to dentin surfaces. Our findings indicate there are two types of osteoclasts with distinct properties.« less

An Experimental Evaluation of Mechanical Properties of Hybrid Reinforcements

NASA Astrophysics Data System (ADS)

Sai Kumar, A.; Ganesan, G.; Karthikeyan, K.

2017-07-01

This paper presents the mechanical properties of unidirectional hybrid reinforcements formed from continuous fibres impregnated with a fibre binding material which are used for reinforcing the concrete. Recently FRP (Fibre Reinforced Polymer) manufacturers and suppliers have been increased all over the world because of the superior performance of FRP products in the construction industry. Its non-corrosive nature has turned the attention of many researchers to make several studies on different type of FRP products. Through a vast research, several standards also have been formulated. In this regard a new combination of FRP materials is tried in this paper and its properties have been derived. Carbon fibre and glass fibres fuse in this study to form a new hybrid rebar. The design properties such as tensile strength, tensile modulus, and compressive strength have been studied as per ASTM standards and it has been identified that the Hybrid rebar show a superior performance in comparison with GFRP (Glass FRP) and Steel rebars. This extraordinary performance of hybrid composite material increases the extensive engineering applications such as transport industry, aeronautics, naval, automotive industries.

The electrostatic properties of Fiber-Reinforced-Plastics double wall underground storage gasoline tanks

NASA Astrophysics Data System (ADS)

Li, Yipeng; Liu, Quanzhen; Meng, He; Sun, Lifu; Zhang, Yunpeng

2013-03-01

At present Fiber Reinforced Plastics (FRP) double wall underground storage gasoline tanks are wildly used. An FRP product with a resistance of more than 1011 Ω is a static non-conductor, so it is difficult for the static electricity in the FRP product to decay into the earth. In this paper an experimental system was built to simulate an automobile gasoline filling station. Some electrostatic parameters of the gasoline, including volume charge density, were tested when gasoline was unloaded into a FRP double wall underground storage tank. Measurements were taken to make sure the volume charge density in the oil-outlet was similar to the volume charge density in the tank. In most cases the volume charge density of the gasoline was more than 22.7 μC m-3, which is likely to cause electrostatic discharge in FRP double wall underground storage gasoline tanks. On the other hand, it would be hard to ignite the vapor by electrostatic discharge since the vapor pressure in the tanks is over the explosion limit. But when the tank is repaired or re-used, the operators must pay attention to the static electricity and some measurements should be taken to avoid electrostatic accident. Besides the relaxation time of charge in the FRP double wall gasoline storage tanks should be longer.

Self-monitoring fiber reinforced polymer strengthening system for civil engineering infrastructures

NASA Astrophysics Data System (ADS)

Jiang, Guoliang; Dawood, Mina; Peters, Kara; Rizkalla, Sami

2008-03-01

Fiber reinforced polymer (FRP) materials are currently used for strengthening civil engineering infrastructures. The strengthening system is dependant on the bond characteristics of the FRP to the external surface of the structure to be effective in resisting the applied loads. This paper presents an innovative self-monitoring FRP strengthening system. The system consists of two components which can be embedded in FRP materials to monitor the global and local behavior of the strengthened structure respectively. The first component of the system is designed to evaluate the applied load acting on a structure based on elongation of the FRP layer along the entire span of the structure. Success of the global system has been demonstrated using a full-scale prestressed concrete bridge girder which was loaded up to failure. The test results indicate that this type of sensor can be used to accurately determine the load prior to failure within 15 percent of the measured value. The second sensor component consists of fiber Bragg grating sensors. The sensors were used to monitor the behavior of steel double-lap shear splices tested under tensile loading up to failure. The measurements were used to identify abnormal structural behavior such as epoxy cracking and FRP debonding. Test results were also compared to numerical values obtained from a three dimensional shear-lag model which was developed to predict the sensor response.

Measuring Radiant Emissions from Entire Prescribed Fires with Ground, Airborne and Satellite Sensors RxCADRE 2012

NASA Technical Reports Server (NTRS)

Dickinson, Matthew B.; Hudak, Andrew T.; Zajkowski, Thomas; Loudermilk, E. Louise; Schroeder, Wilfrid; Ellison, Luke; Kremens, Robert L.; Holley, William; Martinez, Otto; Paxton, Alexander;

2010 Federal Radionavigation Plan

DOT National Transportation Integrated Search

2011-04-15

The Federal Radionavigation Plan (FRP) reflects the official positioning, : navigation, and timing (PNT) policy and planning for the Federal : Government. The FRP covers both terrestrial- and space-based, commonuse, : federally operated PNT systems. ...

The Auckland Optotypes: An open-access pictogram set for measuring recognition acuity.

PubMed

Hamm, Lisa M; Yeoman, Janice P; Anstice, Nicola; Dakin, Steven C

2018-03-01

When measuring recognition acuity in a research setting, the most widely used symbols are the Early Treatment of Diabetic Retinopathy Study (ETDRS) set of 10 Sloan letters. However, the symbols are not appropriate for patients unfamiliar with letters, and acuity for individual letters is variable. Alternative pictogram sets are available, but are generally comprised of fewer items. We set out to develop an open-access set of 10 pictograms that would elicit more consistent estimates of acuity across items than the ETDRS letters from visually normal adults. We measured monocular acuity for individual uncrowded optotypes within a newly designed set (The Auckland Optotype [TAO]), the ETDRS set, and Landolt Cs. Eleven visually normal adults were assessed on regular and vanishing formats of each set. Inter-optotype reliability and ability to detect subtle differences between participants were assessed using intraclass correlations (ICC) and fractional rank precision (FRP). The TAO vanishing set showed the strongest performance (ICC = 0.97, FRP = 0.90), followed by the other vanishing sets (Sloan ICC = 0.88, FRP = 0.74; Landolt ICC = 0.86, FRP = 0.80). Within the regular format, TAO again outperformed the existing sets (TAO ICC = 0.77, FRP = 0.75; Sloan ICC = 0.65, FRP = 0.64; Landolt ICC = 0.48, FRP = 0.63). For adults with normal visual acuity, the new optotypes (in both regular and vanishing formats) are more equally legible and sensitive to subtle individual differences than their Sloan counterparts. As this set does not require observers to be able to name Roman letters, and is freely available to use and modify, it may have wide application for measurement of acuity.

Fit-for-purpose phosphorus management: do riparian buffers qualify in catchments with sandy soils?

PubMed

Weaver, David; Summers, Robert

2014-05-01

Hillslope runoff and leaching studies, catchment-scale water quality measurements and P retention and release characteristics of stream bank and catchment soils were used to better understand reasons behind the reported ineffectiveness of riparian buffers for phosphorus (P) management in catchments with sandy soils from south-west Western Australia (WA). Catchment-scale water quality measurements of 60 % particulate P (PP) suggest that riparian buffers should improve water quality; however, runoff and leaching studies show 20 times more water and 2 to 3 orders of magnitude more P are transported through leaching than runoff processes. The ratio of filterable reactive P (FRP) to total P (TP) in surface runoff from the plots was 60 %, and when combined with leachate, 96 to 99 % of P lost from hillslopes was FRP, in contrast with 40 % measured as FRP at the large catchment scale. Measurements of the P retention and release characteristics of catchment soils (<2 mm) compared with stream bank soil (<2 mm) and the <75-μm fraction of stream bank soils suggest that catchment soils contain more P, are more P saturated and are significantly more likely to deliver FRP and TP in excess of water quality targets than stream bank soils. Stream bank soils are much more likely to retain P than contribute P to streams, and the in-stream mixing of FRP from the landscape with particulates from stream banks or stream beds is a potential mechanism to explain the change in P form from hillslopes (96 to 99 % FRP) to large catchments (40 % FRP). When considered in the context of previous work reporting that riparian buffers were ineffective for P management in this environment, these studies reinforce the notion that (1) riparian buffers are unlikely to provide fit-for-purpose P management in catchments with sandy soils, (2) most P delivered to streams in sandy soil catchments is FRP and travels via subsurface and leaching pathways and (3) large catchment-scale water quality measurements

Fire Detections and Fire Radiative Power Intercomparison Using Multiple Sensor Products over a Predominantly Gas Flaring Region

NASA Astrophysics Data System (ADS)

Sharma, A.; Wang, J.

2014-12-01

Gas flaring is a global environmental hazard severely impacting climate, economy and public health. The associated emissions are frequently unreported and have large uncertainties. Prior studies have established a direct relationship between radiative energy released from fires and the biomass burned, making fire radiative power (FRP), i.e., the rate of radiative energy release, an important proxy to characterize emissions. In this study fire properties from four different satellite products were obtained over a 10⁰ x 10⁰ gas flaring region in Russia for all days of May 2013. The target area is part of Russia's biggest gas flaring region, Khanty-Mansiysk autonomous okrug. The objective of the study is to investigate the consistency of fire detections, FRP retrievals and effects of gridding FRP data from the region on a uniform grid. The four products used were: MODIS Terra level2 thermal anomalies (MOD14), MODIS Aqua level2 thermal anomalies (MYD14), VIIRS Active fire product and a recent NOAA Nightfire product. 1 km nominal resolution FRP from MOD14 AND MYD14, subpixel radiant heat (RH) from NOAA Nightfire product and fire detections from all four products were recorded on a 0.25⁰ x 0.25⁰ grid on a daily basis. Results revealed the Nightfire product had maximum detections, almost six times the number of detections by other products, mainly because of the use of M10 (1.6 µm) band as their primary detection band. The M10 band is highly efficient in identifying radiant emissions from hot sources during night-time. The correlation (after omitting outliers) between gridded NOAA Nightfire RH and corresponding MOD14 FRP and MYD14 FRP gave a moderate regression value, with MODIS FRP being mostly higher than RH. As an extension to this work, a comprehensive study for a larger temporal domain also incorporating viewing geometries and cloud cover would advance our understanding of flare detections and associated FRP retrievals not just for the target region but also

Pultruded composites using soy-based polyurethane resin.

DOT National Transportation Integrated Search

2008-07-01

Fiber Reinforced Polymer (FRP) composites offer inherent advantages over traditional materials with regard to high strength-to-weight ratio, design flexibility, corrosion resistance, low maintenance, and extended service life. FRP materials can be us...

Evaluation of steering control devices in adapted cars using sled deceleration tests

NASA Astrophysics Data System (ADS)

Eixerés, B.; Masiá, J.; Dols, J. F.; Esquerdo, T. V.

2009-11-01

Steering control devices used by disabled drivers can reduce passive safety, interfering with the existing systems of safety in the vehicle or causing injury to the occupants [1]. In this article, the results obtained in different dynamic tests carried out in a crash test simulator are presented. These tests were carried out on the steering devices which interfere the most with the deployment of the driver's airbag and also with the knee airbag in a Citroen C5.

Finite element comparison of human and Hybrid III responses in a frontal impact.

PubMed

Danelson, Kerry A; Golman, Adam J; Kemper, Andrew R; Gayzik, F Scott; Clay Gabler, H; Duma, Stefan M; Stitzel, Joel D

2015-12-01

The improvement of finite element (FE) Human Body Models (HBMs) has made them valuable tools for investigating restraint interactions compared to anthropomorphic test devices (ATDs). The objective of this study was to evaluate the effect of various combinations of safety restraint systems on the sensitivity of thoracic injury criteria using matched ATD and Human Body Model (HBM) simulations at two crash severities. A total of seven (7) variables were investigated: 3-point belt with two (2) load limits, frontal airbag, knee bolster airbag, a buckle pretensioner, and two (2) delta-v's - 40kph and 50kph. Twenty four (24) simulations were conducted for the Hybrid III ATD FE model and repeated with a validated HBM for 48 total simulations. Metrics tested in these conditions included sternum deflection, chest acceleration, chest excursion, Viscous Criteria (V*C) criteria, pelvis acceleration, pelvis excursion, and femur forces. Additionally, chest band deflection and rib strain distribution were measured in the HBM for additional restraint condition discrimination. The addition of a frontal airbag had the largest effect on the occupant chest metrics with an increase in chest compression and acceleration but a decrease in excursion. While the THUMS and Hybrid III occupants demonstrated the same trend in the chest compression measurements, there were conflicting results in the V*C, acceleration, and displacement metrics. Similarly, the knee bolster airbag had the largest effect on the pelvis with a decrease in acceleration and excursion. With a knee bolster airbag the simulated occupants gave conflicting results, the THUMS had a decrease in femur force and the ATD had an increase. Preferential use of dummies or HBM's is not debated; however, this study highlights the ability of HBM metrics to capture additional chest response metrics. Copyright © 2015 Elsevier Ltd. All rights reserved.

2012 Federal Radionavigation Plan.

DOT National Transportation Integrated Search

2012-01-01

The Federal Radionavigation Plan (FRP) reflects the official positioning, : navigation, and timing (PNT) policy and planning for the Federal : Government. Within the construct of the National PNT Architecture, the : FRP covers both terrestrial- and s...

2014 Federal Radionavigation Plan.

DOT National Transportation Integrated Search

2015-01-01

The Federal Radionavigation Plan (FRP) reflects the official positioning, : navigation, and timing (PNT) policy and planning for the Federal : Government. Within the construct of the National PNT Architecture, the : FRP covers both terrestrial- and s...

2017 Federal Radionavigation Plan.

DOT National Transportation Integrated Search

2017-01-01

The Federal Radionavigation Plan (FRP) reflects the official positioning, navigation, and timing (PNT) policy and planning for the Federal Government. Within the construct of the National PNT Architecture, the FRP covers both terrestrial- and space-b...

Research notes : modeling a composite reinforced bridge.

DOT National Transportation Integrated Search

2001-06-01

In 1998, Oregon Department of Transportation (ODOT) used fiber reinforced polymer (FRP) composites to strengthen the historic Horsetail Falls Bridge. Because this was the first experience with FRP composites, research was conducted to verify that the...

Plate & tube bridge deck evaluation in the deck test bed of the Troutville, Virginia, weigh station.

DOT National Transportation Integrated Search

2004-01-01

This report addresses the laboratory and field performance of multi-cellular fiber-reinforced polymer (FRP) composite bridge deck systems. We focus specifically on FRP decks produced from adhesively bonded pultrusions where the core of the deck posse...

Balance between fibroblast growth factor 10 and secreted frizzled-relate protein-1 controls the development of hair follicle by competitively regulating β-catenin signaling.

PubMed

Zhang, Haihua; Nan, Weixiao; Wang, Shiyong; Si, Huazhe; Li, Guangyu

2018-07-01

Growth of hairs depends on the regular development of hair follicles which are hypothesized to be regulated by fibroblast growth factor 10 (FGF10) and secreted frizzled-relate protein-1 (sFRP1). In the current study, the effect of FGF10 or sFRP1 on hair follicle cells was assessed and the possible mechanism mediating the interaction between FGF10 and sFRP1 in hair follicle cells was explored. Out root sheath (ORS) and dermal papilla (DP) cells were isolated from mink skin tissues and subjected to administrations of FGF10 (50 ng/ml) or sFRP1 (10 ng/ml). Then proliferation, cell cycle distribution, and migration potentials of both cell types were detected. Moreover, the nuclear translocation of β-catenin was determined. The results showed that the administration of FGF10 increased cell proliferation and migration potential in both cell types, which was associated with the up-regulated nuclear level of β-catenin. To the contrary, the administration of sFRP1 decreased cell proliferation and migration potentials while induced the G1 cell cycle arrest in both cell types by inhibiting nuclear translocation of β-catenin. Compared with the sole administrations, the co-treatment of FGF10 and sFRP1 had a medium effect on cell proliferation, cell cycle distribution, cell migration, and nuclear β-catenin level, representing an antagonistic interaction between the two factors, which was exerted by competitively regulating β-catenin pathway. Conclusively, the cycle of hair follicles was promoted by FGF10 while blocked by sFRP1 and the interplay between the two factors controlled the development of hair follicles by competitively regulating β-catenin signaling. Copyright © 2018. Published by Elsevier Masson SAS.

Multidisciplinary intensive functional restoration versus outpatient active physiotherapy in chronic low back pain: a randomized controlled trial.

PubMed

Roche-Leboucher, Ghislaine; Petit-Lemanac'h, Audrey; Bontoux, Luc; Dubus-Bausière, Valérie; Parot-Shinkel, Elsa; Fanello, Serge; Penneau-Fontbonne, Dominique; Fouquet, Natacha; Legrand, Erick; Roquelaure, Yves; Richard, Isabelle

2011-12-15

Randomized parallel group comparative trial with a 1-year follow-up period. To compare in a population of patients with chronic low back pain, the effectiveness of a functional restoration program (FRP), including intensive physical training and a multidisciplinary approach, with an outpatient active physiotherapy program at 1-year follow-up. Controlled studies conducted in the United States and in Northern Europe showed a benefit of FRPs, especially on return to work. Randomized studies have compared these programs with standard care. A previously reported study presented the effectiveness at 6 months of both functional restoration and active physiotherapy, with a significantly greater reduction of sick-leave days for functional restoration. A total of 132 patients with low back pain were randomized to either FRP (68 patients) or active individual therapy (64 patients). One patient did not complete the FRP; 19 patients were lost to follow-up (4 in the FRP group and 15 in the active individual treatment group). The number of sick-leave days in 2 years before the program was similar in both groups (180 ± 135.1 days in active individual treatment vs. 185 ± 149.8 days in FRP, P = 0.847). In both groups, at 1-year follow-up, intensity of pain, flexibility, trunk muscle endurance, Dallas daily activities and work and leisure scores, and number of sick-leave days were significantly improved compared with baseline. The number of sick-leave days was significantly lower in the FRP group. Both programs are efficient in reducing disability and sick-leave days. The FRP is significantly more effective in reducing sick-leave days. Further analysis is required to determine if this overweighs the difference in costs of both programs.

Quantitative Evaluation of MODIS Fire Radiative Power Measurement for Global Smoke Emissions Assessment

NASA Technical Reports Server (NTRS)

Ichoku, Charles; Ellison, Luke

2011-01-01

Satellite remote sensing is providing us tremendous opportunities to measure the fire radiative energy (FRE) release rate or power (FRP) from open biomass burning, which affects many vegetated regions of the world on a seasonal basis. Knowledge of the biomass burning characteristics and emission source strengths of different (particulate and gaseous) smoke constituents is one of the principal ingredients upon which the assessment, modeling, and forecasting of their distribution and impacts depend. This knowledge can be gained through accurate measurement of FRP, which has been shown to have a direct relationship with the rates of biomass consumption and emissions of major smoke constituents. Over the last decade or so, FRP has been routinely measured from space by both the MODIS sensors aboard the polar orbiting Terra and Aqua satellites, and the SEVIRI sensor aboard the Meteosat Second Generation (MSG) geostationary satellite. During the last few years, FRP has steadily gained increasing recognition as an important parameter for facilitating the development of various scientific studies and applications relating to the quantitative characterization of biomass burning and their emissions. To establish the scientific integrity of the FRP as a stable quantity that can be measured consistently across a variety of sensors and platforms, with the potential of being utilized to develop a unified long-term climate data record of fire activity and impacts, it needs to be thoroughly evaluated, calibrated, and validated. Therefore, we are conducting a detailed analysis of the FRP products from MODIS to evaluate the uncertainties associated with them, such as those due to the effects of satellite variable observation geometry and other factors, in order to establish their error budget for use in diverse scientific research and applications. In this presentation, we will show recent results of the MODIS FRP uncertainty analysis and error mitigation solutions, and demonstrate

Active muscle response contributes to increased injury risk of lower extremity in occupant-knee airbag interaction.

PubMed

Nie, Bingbing; Sathyanarayan, Deepak; Ye, Xin; Crandall, Jeff R; Panzer, Matthew B

2018-02-28

Recent field data analysis has demonstrated that knee airbags (KABs) can reduce occupant femur and pelvis injuries but may be insufficient to decrease leg injuries in motor vehicle crashes. An enhanced understanding of the associated injury mechanisms requires accurate assessment of physiological-based occupant parameters, some of which are difficult or impossible to obtain from experiments. This study sought to explore how active muscle response can influence the injury risk of lower extremities during KAB deployment using computational biomechanical analysis. A full-factorial matrix, consisting of 48 finite element simulations of a 50th percentile occupant human model in a simplified vehicle interior, was designed. The matrix included 32 new cases in combination with 16 previously reported cases. The following influencing factors were taken into account: muscle activation, KAB use, KAB design, pre-impact seating position, and crash mode. Responses of 32 lower extremity muscles during emergency braking were replicated using one-dimensional elements of a Hill-type constitutive model, with the activation level determined from inverse dynamics and validated by existing volunteer tests. Dynamics of unfolding and inflating of the KABs were represented using the state-of-the-art corpuscular particle method. Abbreviated Injury Scale (AIS) 2+ injury risks of the knee-thigh-hip (KTH) complex and the tibia were assessed using axial force and resultant bending moments. With all simulation cases being taken together, a general linear model was used to assess factor significance (P <.05). As estimated by the regression model across all simulation cases, use of KABs significantly reduced axial femur forces by 4.74 ± 0.43 kN and AIS 2+ injury risk of KTH by 47 ± 6% (P <.05) but did not provide substantial change to injury risk of leg fractures. Muscle activation significantly increased axial force and bending moment of the femur (3.87 ± 0.38 kN and 64.3 ± 5.9 Nm), the

Detailed Evaluation of MODIS Fire Radiative Power Measurements

NASA Technical Reports Server (NTRS)

Ichoku, Charles

2010-01-01

Satellite remote sensing is providing us tremendous opportunities to measure the fire radiative energy (FRE) release rate or power (FRP) from open biomass burning, which affects many vegetated regions of the world on a seasonal basis. Knowledge of the biomass burning characteristics and emission source strengths of different (particulate and gaseous) smoke constituents is one of the principal ingredients upon which the assessment, modeling, and forecasting of their distribution and impacts depend. This knowledge can be gained through accurate measurement of FRP, which has been shown to have a direct relationship with the rates of biomass consumption and emissions of major smoke constituents. Over the last decade or so, FRP has been routinely measured from space by both the MODIS sensors aboard the polar orbiting Terra and Aqua satellites, and the SEVIRI sensor aboard the Meteosat Second Generation (MSG) geostationary satellite. During the last few years, FRP has been gaining recognition as an important parameter for facilitating the development of various scientific studies relating to the quantitative characterization of biomass burning and their emissions. Therefore, we are conducting a detailed analysis of the FRP products from MODIS to characterize the uncertainties associated with them, such as those due to the MODIS bow-tie effects and other factors, in order to establish their error budget for use in scientific research and applications. In this presentation, we will show preliminary results of the MODIS FRP data analysis, including comparisons with airborne measurements.

Numerical Study on Deflection Behaviour of Concrete Beams Reinforced with GFRP Bars

NASA Astrophysics Data System (ADS)

Mohamed, Osama A.; Khattab, Rania; Hawat, Waddah Al

2017-10-01

Fiber-Reinforced Polymer (FRP) bars are gaining popularity as sustainable alternatives to conventional reinforcing steel bars in reinforced concrete applications. The production of FRP bars has lower environmental impact compared to steel reinforcing bars. In addition, the non-corroding FRP materials can potentially decrease the cost or need for maintenance of reinforced concrete structural elements, especially in harsh environmental conditions that can impact both concrete and reinforcement. FRP bars offer additional favourable properties including high tensile strength and low unit weight. However, the mechanical properties of FRP bars can lead to large crack widths and deflections. The objective of this study is to investigate the deflection behaviour of concrete beams reinforced with Glass FRP (GFRP) bars as a longitudinal main reinforcement. Six concrete beams reinforced with GFRP bars were modelled using the finite element computer program ANSYS. The main variable considered in the study is the reinforcement ratio. The deflection equations in current North American codes including ACI 440.1R-06, ACI 440.1R-15 and CSA S806-12 are used to compute deflections, and these are compared to numerical results. It was concluded in this paper that deflections predicted by ACI 440.1R-06 equations are lower than the numerical analysis results while ACI 440.1R-15 is in agreement with numerical analysis with tendency to be conservative. The values of deflections estimated by CSA S806-12 formulas are consistent with results of numerical analysis.

Development and performance evaluation of fiber reinforced polymer bridge.

DOT National Transportation Integrated Search

2014-03-01

Fiber reinforced polymers (FRP) have become more popular construction materials in the last decade due to the reduction of : material costs. The installation and performance evaluation of the first FRP-wrapped balsa wood bridge in Louisiana is descri...

Behavior of concrete specimens reinforced with composite materials : laboratory study

DOT National Transportation Integrated Search

2000-02-01

The main objective of this study was to investigate the interaction between FRP composite and concrete by addressing the most important : variables in terms of FRP (fiber reinforced polymer) properties. Type of fibers, thickness of the laminates, fib...

Development of cost-effective VARTM technology for repair and hardening design method and specifications for ALDOT contractor : phase 3.

DOT National Transportation Integrated Search

2013-04-01

Resin infusion, a method of fabricating fiber reinforced polymer (FRP), has been shown to produce a stronger FRP of : more consistent quality than other methods. It is a preferred method of fabrication in industries like automotive, : aerospace, and ...

Nondestructive evaluation of fiber reinforced polymer bridges and decks.

DOT National Transportation Integrated Search

2003-10-01

The research described herein involved both nondestructive evaluation and destructive testing of an FRP honeycomb specimen. The specimen is representative of an FRP bridge that is to be constructed in Troupsburg, New York. The specimen was tested in ...

Automated infrasound signal detection algorithms implemented in MatSeis - Infra Tool.

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

Hart, Darren

2004-07-01

MatSeis's infrasound analysis tool, Infra Tool, uses frequency slowness processing to deconstruct the array data into three outputs per processing step: correlation, azimuth and slowness. Until now, an experienced analyst trained to recognize a pattern observed in outputs from signal processing manually accomplished infrasound signal detection. Our goal was to automate the process of infrasound signal detection. The critical aspect of infrasound signal detection is to identify consecutive processing steps where the azimuth is constant (flat) while the time-lag correlation of the windowed waveform is above background value. These two statements describe the arrival of a correlated set of wavefrontsmore » at an array. The Hough Transform and Inverse Slope methods are used to determine the representative slope for a specified number of azimuth data points. The representative slope is then used in conjunction with associated correlation value and azimuth data variance to determine if and when an infrasound signal was detected. A format for an infrasound signal detection output file is also proposed. The detection output file will list the processed array element names, followed by detection characteristics for each method. Each detection is supplied with a listing of frequency slowness processing characteristics: human time (YYYY/MM/DD HH:MM:SS.SSS), epochal time, correlation, fstat, azimuth (deg) and trace velocity (km/s). As an example, a ground truth event was processed using the four-element DLIAR infrasound array located in New Mexico. The event is known as the Watusi chemical explosion, which occurred on 2002/09/28 at 21:25:17 with an explosive yield of 38,000 lb TNT equivalent. Knowing the source and array location, the array-to-event distance was computed to be approximately 890 km. This test determined the station-to-event azimuth (281.8 and 282.1 degrees) to within 1.6 and 1.4 degrees for the Inverse Slope and Hough Transform detection algorithms

Analytical, Numerical and Experimental Examination of Reinforced Composites Beams Covered with Carbon Fiber Reinforced Plastic

NASA Astrophysics Data System (ADS)

Kasimzade, A. A.; Tuhta, S.

2012-03-01

In the article, analytical, numerical (Finite Element Method) and experimental investigation results of beam that was strengthened with fiber reinforced plastic-FRP composite has been given as comparative, the effect of FRP wrapping number to the maximum load and moment capacity has been evaluated depending on this results. Carbon FRP qualitative dependences have been occurred between wrapping number and beam load and moment capacity for repair-strengthen the reinforced concrete beams with carbon fiber. Shown possibilities of application traditional known analysis programs, for the analysis of Carbon Fiber Reinforced Plastic (CFRP) strengthened structures.

Research in biomechanics of occupant protection.

PubMed

King, A I; Yang, K H

1995-04-01

This paper discusses the biomechanical bases for occupant protection against frontal and side impact. Newton's Laws of Motion are used to illustrate the effect of a crash on restrained and unrestrained occupants, and the concept of ride down is discussed. Occupant protection through the use of energy absorbing materials is described, and the mechanism of injury of some of the more common injuries is explained. The role of the three-point belt and the airbag in frontal protection is discussed along with the potential injuries that can result from the use of these restraint systems. Side impact protection is more difficult to attain but some protection can be derived from the use of padding or a side impact airbag. It is concluded that the front seat occupants are adequately protected against frontal impact if belts are worn in an airbag equipped vehicle. Side impact protection may not be uniform in all vehicles.

Field performance of a geosynthetic clay liner landfill capping system under simulated waste subsidence

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

Weiss, W.; Siegmund, M.; Alexiew, D.

1995-10-01

A flexible landfill capping system consisting of a 3-D-geocore composite for gas vent, a Geosynthetic Clay Liner (GCL) for sealing and a 3-D-geocore composite for drainage of the vegetation soil was built on a test field at Michelshoehe landfill near Weimar, Germany. At four locations airbags were installed underneath the thin capping system to simulate subsidences. On top of three of these airbags overlaps of the GCL were positioned, for comparison there was no overlap at the fourth location. After hydratation of the GCL the airbags were de-aerated and subsidences occurred with app. 5 % tensile strain in the GCL.more » For three weeks the test field was intensively sprinkled in intervals. Then horizontal and vertical deformations were measured, but not displacements were registered in the overlaps. The evaluation of the GCL`s permeability showed no significant difference between the locations with and without overlaps.« less

Bridge-in-a-backpack(TM) task 4 : development of improved arch concrete mix to facilitate field use.

DOT National Transportation Integrated Search

2016-02-01

This report includes fulfillment of Task 4 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 4 investigates the development of improved concrete mixes for filling the FRP : tubes. : One critica...

Bridge-in-a-Backpack(TM) task 4 : development of improved arch concrete mix to facilitate field use.

DOT National Transportation Integrated Search

2016-02-01

This report includes fulfillment of Task 4 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 4 investigates the development of improved concrete mixes for filling the FRP : tubes. : One critica...

Fiber reinforced polymer bridge decks : [technical summary].

DOT National Transportation Integrated Search

2011-01-01

A number of researchers have addressed the use of Fiber Reinforced Polymer (FRP) deck as a replacement solution for deteriorated bridge decks made of traditional materials. The use of new, advanced materials such as FRP is advantageous when the bridg...

Predicting the occurrence of embolic events: an analysis of 1456 episodes of infective endocarditis from the Italian Study on Endocarditis (SEI).

PubMed

Rizzi, Marco; Ravasio, Veronica; Carobbio, Alessandra; Mattucci, Irene; Crapis, Massimo; Stellini, Roberto; Pasticci, Maria Bruna; Chinello, Pierangelo; Falcone, Marco; Grossi, Paolo; Barbaro, Francesco; Pan, Angelo; Viale, Pierluigi; Durante-Mangoni, Emanuele

2014-04-29

Embolic events are a major cause of morbidity and mortality in patients with infective endocarditis. We analyzed the database of the prospective cohort study SEI in order to identify factors associated with the occurrence of embolic events and to develop a scoring system for the assessment of the risk of embolism. We retrospectively analyzed 1456 episodes of infective endocarditis from the multicenter study SEI. Predictors of embolism were identified. Risk factors identified at multivariate analysis as predictive of embolism in left-sided endocarditis, were used for the development of a risk score: 1 point was assigned to each risk factor (total risk score range: minimum 0 points; maximum 2 points). Three categories were defined by the score: low (0 points), intermediate (1 point), or high risk (2 points); the probability of embolic events per risk category was calculated for each day on treatment (day 0 through day 30). There were 499 episodes of infective endocarditis (34%) that were complicated by ≥ 1 embolic event. Most embolic events occurred early in the clinical course (first week of therapy: 15.5 episodes per 1000 patient days; second week: 3.7 episodes per 1000 patient days). In the total cohort, the factors associated with the occurrence of embolism at multivariate analysis were prosthetic valve localization (odds ratio, 1.84), right-sided endocarditis (odds ratio, 3.93), Staphylococcus aureus etiology (odds ratio, 2.23) and vegetation size ≥ 13 mm (odds ratio, 1.86). In left-sided endocarditis, Staphylococcus aureus etiology (odds ratio, 2.1) and vegetation size ≥ 13 mm (odds ratio, 2.1) were independently associated with embolic events; the 30-day cumulative incidence of embolism varied with risk score category (low risk, 12%; intermediate risk, 25%; high risk, 38%; p < 0.001). Staphylococcus aureus etiology and vegetation size are associated with an increased risk of embolism. In left-sided endocarditis, a simple scoring system

Predicting the occurrence of embolic events: an analysis of 1456 episodes of infective endocarditis from the Italian Study on Endocarditis (SEI)

PubMed Central

2014-01-01

Background Embolic events are a major cause of morbidity and mortality in patients with infective endocarditis. We analyzed the database of the prospective cohort study SEI in order to identify factors associated with the occurrence of embolic events and to develop a scoring system for the assessment of the risk of embolism. Methods We retrospectively analyzed 1456 episodes of infective endocarditis from the multicenter study SEI. Predictors of embolism were identified. Risk factors identified at multivariate analysis as predictive of embolism in left-sided endocarditis, were used for the development of a risk score: 1 point was assigned to each risk factor (total risk score range: minimum 0 points; maximum 2 points). Three categories were defined by the score: low (0 points), intermediate (1 point), or high risk (2 points); the probability of embolic events per risk category was calculated for each day on treatment (day 0 through day 30). Results There were 499 episodes of infective endocarditis (34%) that were complicated by ≥ 1 embolic event. Most embolic events occurred early in the clinical course (first week of therapy: 15.5 episodes per 1000 patient days; second week: 3.7 episodes per 1000 patient days). In the total cohort, the factors associated with the occurrence of embolism at multivariate analysis were prosthetic valve localization (odds ratio, 1.84), right-sided endocarditis (odds ratio, 3.93), Staphylococcus aureus etiology (odds ratio, 2.23) and vegetation size ≥ 13 mm (odds ratio, 1.86). In left-sided endocarditis, Staphylococcus aureus etiology (odds ratio, 2.1) and vegetation size ≥ 13 mm (odds ratio, 2.1) were independently associated with embolic events; the 30-day cumulative incidence of embolism varied with risk score category (low risk, 12%; intermediate risk, 25%; high risk, 38%; p < 0.001). Conclusions Staphylococcus aureus etiology and vegetation size are associated with an increased risk of embolism. In left

Recent advances in the Lesser Antilles observatories Part 1 : Seismic Data Acquisition Design based on EarthWorm and SeisComP

NASA Astrophysics Data System (ADS)

Saurel, Jean-Marie; Randriamora, Frédéric; Bosson, Alexis; Kitou, Thierry; Vidal, Cyril; Bouin, Marie-Paule; de Chabalier, Jean-Bernard; Clouard, Valérie

2010-05-01

Lesser Antilles observatories are in charge of monitoring the volcanoes and earthquakes in the Eastern Caribbean region. During the past two years, our seismic networks have evolved toward a full digital technology. These changes, which include modern three components sensors, high dynamic range digitizers, high speed terrestrial and satellite telemetry, improve data quality but also increase the data flows to process and to store. Moreover, the generalization of data exchange to build a wide virtual seismic network around the Caribbean domain requires a great flexibility to provide and receive data flows in various formats. As many observatories, we have decided to use the most popular and robust open source data acquisition systems in use in today observatories community : EarthWorm and SeisComP. The first is renowned for its ability to process real time seismic data flows, with a high number of tunable modules (filters, triggers, automatic pickers, locators). The later is renowned for its ability to exchange seismic data using the international SEED standard (Standard for Exchange of Earthquake Data), either by producing archive files, or by managing output and input SEEDLink flows. French Antilles Seismological and Volcanological Observatories have chosen to take advantage of the best features of each software to design a new data flow scheme and to integrate it in our global observatory data management system, WebObs [Beauducel et al., 2004]1, see the companion paper (Part 2). We assigned the tasks to the different softwares, regarding their main abilities : - EarthWorm first performs the integration of data from different heterogeneous sources; - SeisComP takes all this homogeneous EarthWorm data flow, adds other sources and produces SEED archives and SEED data flow; - EarthWorm is then used again to process this clean and complete SEEDLink data flow, mainly producing triggers, automatic locations and alarms; - WebObs provides a friendly human interface, both

The stress-strain relationships in wood and fiber-reinforced plastic laminae of reinforced glued-laminated wood beams

NASA Astrophysics Data System (ADS)

Tingley, Daniel Arthur

The reinforcement of wood and wood composite structural products to improve their mechanical properties has been in practice for many years. Recently, the use of high-strength fiber-reinforced plastic (FRP) as a reinforcement in such applications has been commercialized. The reinforcement is manufactured using a standard pultrusion process or alternatively a sheet-forming process commonly referred to as "pulforming". The high-modulus fibers are predominately unidirectional, although off-axis fibers are often used to enhance off-axis properties. The fibers used are either of a single type or multiple types, which are called "hybrids". Unidirectional, single, and hybrid fiber FRP physical properties and characteristics were compared to wood. Full-scale reinforced glulams were tested. Aramid-reinforced plastics (ARP) used as tensile reinforcements were found to be superior in strength applications to other types of FRP made with fiber, such as carbon and fiberglass. Carbon/aramid-reinforced plastic (CARP) was shown to be superior in both modulus and strength design situations. Fiberglass was shown to be suitable only in hybrid situations with another fiber such as aramid or carbon and only in limited use situations where modulus was a design criteria. The testing and analysis showed that the global response of reinforced glulam beams is controlled by localized strength variations in the wood such as slope of grain, knots, finger joints, etc. in the tensile zone. The elemental tensile strains in the extreme wood tensile laminae, due to global applied loads, were found to be well below the strain at failure in clear wood samples recovered from the failure area. Two areas affecting the relationship between the wood and the FRP were investigated: compatibility of the wood and FRP materials and interface characteristics between the wood and FRP. The optimum strain value at yield point for an FRP was assessed to be slightly higher than the clear wood value in tension for a

Structural Behavior of Concrete Beams Reinforced with Basalt Fiber Reinforced Polymer (BFRP) Bars

NASA Astrophysics Data System (ADS)

Ovitigala, Thilan

The main challenge for civil engineers is to provide sustainable, environmentally friendly and financially feasible structures to the society. Finding new materials such as fiber reinforced polymer (FRP) material that can fulfill the above requirements is a must. FRP material was expensive and it was limited to niche markets such as space shuttles and air industry in the 1960s. Over the time, it became cheaper and spread to other industries such as sporting goods in the 1980-1990, and then towards the infrastructure industry. Design and construction guidelines are available for carbon fiber reinforced polymer (CFRP), aramid fiber reinforced polymer (AFRP) and glass fiber reinforced polymer (GFRP) and they are currently used in structural applications. Since FRP is linear elastic brittle material, design guidelines for the steel reinforcement are not valid for FRP materials. Corrosion of steel reinforcement affects the durability of the concrete structures. FRP reinforcement is identified as an alternative to steel reinforcement in corrosive environments. Although basalt fiber reinforced polymer (BFRP) has many advantages over other FRP materials, but limited studies have been done. These studies didn't include larger BFRP bar diameters that are mostly used in practice. Therefore, larger beam sizes with larger BFRP reinforcement bar diameters are needed to investigate the flexural and shear behavior of BFRP reinforced concrete beams. Also, shear behavior of BFRP reinforced concrete beams was not yet studied. Experimental testing of mechanical properties and bond strength of BFRP bars and flexural and shear behavior of BFRP reinforced concrete beams are needed to include BFRP reinforcement bars in the design codes. This study mainly focuses on the use of BFRP bars as internal reinforcement. The test results of the mechanical properties of BFRP reinforcement bars, the bond strength of BFRP reinforcement bars, and the flexural and shear behavior of concrete beams

A novel gene's role in an ancient mechanism: secreted Frizzled-related protein 1 is a critical component in the anterior-posterior Wnt signaling network that governs the establishment of the anterior neuroectoderm in sea urchin embryos.

PubMed

Khadka, Anita; Martínez-Bartolomé, Marina; Burr, Stephanie D; Range, Ryan C

2018-01-01

The anterior neuroectoderm (ANE) in many deuterostome embryos (echinoderms, hemichordates, urochordates, cephalochordates, and vertebrates) is progressively restricted along the anterior-posterior axis to a domain around the anterior pole. In the sea urchin embryo, three integrated Wnt signaling branches (Wnt/β-catenin, Wnt/JNK, and Wnt/PKC) govern this progressive restriction process, which begins around the 32- to 60-cell stage and terminates by the early gastrula stage. We previously have established that several secreted Wnt modulators of the Dickkopf and secreted Frizzled-related protein families (Dkk1, Dkk3, and sFRP-1/5) are expressed within the ANE and play important roles in modulating the Wnt signaling network during this process. In this study, we use morpholino and dominant-negative interference approaches to characterize the function of a novel Frizzled-related protein, secreted Frizzled-related protein 1 (sFRP-1), during ANE restriction. sFRP-1 appears to be related to a secreted Wnt modulator, sFRP3/4, that is essential to block Wnt signaling and establish the ANE in vertebrates. Here, we show that the sea urchin sFRP3/4 orthologue is not expressed during ANE restriction in the sea urchin embryo. Instead, our results indicate that ubiquitously expressed maternal sFRP-1 and Fzl1/2/7 signaling act together as early as the 32- to 60-cell stage to antagonize the ANE restriction mechanism mediated by Wnt/β-catenin and Wnt/JNK signaling. Then, starting from the blastula stage, Fzl5/8 signaling activates zygotic sFRP-1 within the ANE territory, where it works with the secreted Wnt antagonist Dkk1 (also activated by Fzl5/8 signaling) to antagonize Wnt1/Wnt8-Fzl5/8-JNK signaling in a negative feedback mechanism that defines the outer ANE territory boundary. Together, these data indicate that maternal and zygotic sFRP-1 protects the ANE territory by antagonizing the Wnt1/Wnt8-Fzl5/8-JNK signaling pathway throughout ANE restriction, providing precise

Using JPSS VIIRS Fire Radiative Power Data to Forecast Biomass Burning Emissions and Smoke Transport by the High Resolution Rapid Refresh Model

NASA Astrophysics Data System (ADS)

Ahmadov, R.; Grell, G. A.; James, E.; Alexander, C.; Stewart, J.; Benjamin, S.; McKeen, S. A.; Csiszar, I. A.; Tsidulko, M.; Pierce, R. B.; Pereira, G.; Freitas, S. R.; Goldberg, M.

2017-12-01

We present a new real-time smoke modeling system, the High Resolution Rapid Refresh coupled with smoke (HRRR-Smoke), to simulate biomass burning (BB) emissions, plume rise and smoke transport in real time. The HRRR is the NOAA Earth System Research Laboratory's 3km grid spacing version of the Weather Research and Forecasting (WRF) model used for weather forecasting. Here we make use of WRF-Chem (the WRF model coupled with chemistry) and simulate fine particulate matter (smoke) emissions emitted by BB. The HRRR-Smoke modeling system ingests fire radiative power (FRP) data from the Visible Infrared Imaging Radiometer Suite (VIIRS) sensor on the Suomi National Polar-orbiting Partnership (S-NPP) satellite to calculate BB emissions. The FRP product is based on processing 750m resolution "M" bands. The algorithms for fire detection and FRP retrieval are consistent with those used to generate the MODIS fire detection data. For the purpose of ingesting VIIRS fire data into the HRRR-Smoke model, text files are generated to provide the location and detection confidence of fire pixels, as well as FRP. The VIIRS FRP data from the text files are processed and remapped over the HRRR-Smoke model domains. We process the FRP data to calculate BB emissions (smoldering part) and fire size for the model input. In addition, HRRR-Smoke uses the FRP data to simulate the injection height for the flaming emissions using concurrently simulated meteorological fields by the model. Currently, there are two 3km resolution domains covering the contiguous US and Alaska which are used to simulate smoke in real time. In our presentation, we focus on the CONUS domain. HRRR-Smoke is initialized 4 times per day to forecast smoke concentrations for the next 36 hours. The VIIRS FRP data, as well as near-surface and vertically integrated smoke mass concentrations are visualized for every forecast hour. These plots are provided to the public via the HRRR-Smoke web-page: https

46 CFR 160.135-11 - Fabrication of prototype lifeboats for approval.

Code of Federal Regulations, 2013 CFR

2013-10-01

.... The Commandant may prescribe additional prototype tests and inspections necessary to maintain quality... inspecting— (i) Fiber Reinforced Plastic (FRP) Construction. (A) FRP components of each prototype lifeboat... system; (vii) Installation of the steering system; and (viii) Installation of the water spray fire...

46 CFR 160.135-11 - Fabrication of prototype lifeboats for approval.

Code of Federal Regulations, 2012 CFR

2012-10-01

.... The Commandant may prescribe additional prototype tests and inspections necessary to maintain quality... inspecting— (i) Fiber Reinforced Plastic (FRP) Construction. (A) FRP components of each prototype lifeboat... system; (vii) Installation of the steering system; and (viii) Installation of the water spray fire...

46 CFR 160.135-11 - Fabrication of prototype lifeboats for approval.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... The Commandant may prescribe additional prototype tests and inspections necessary to maintain quality... inspecting— (i) Fiber Reinforced Plastic (FRP) Construction. (A) FRP components of each prototype lifeboat... system; (vii) Installation of the steering system; and (viii) Installation of the water spray fire...

Bridge-in-a-backpack(TM) : task 3.2: investigating soil - structure interaction - modeling and experimental results of steel arches.

DOT National Transportation Integrated Search

2015-07-01

This report includes fulfillment of Task 3.2 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 3 is an investigation of soil-structure interaction for the FRP tubes. Task 3.2 is the : modeling ...

Bridge-in-a-Backpack(TM). Task 2.3 : low-rise arch study with soil-structure interaction and spread footing foundation.

DOT National Transportation Integrated Search

2015-01-01

This report includes fulfillment of Task 2.3 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 2 is an investigation of alternative shapes for the FRP tubes with varying radii. Task : 2.3 explo...

Bridge-in-a-Backpack(TM). Task 2.1 and 2.2 : investigate alternative shapes with varying radii.

DOT National Transportation Integrated Search

2015-02-01

This report includes fulfillment of Tasks 2.1 and 2.2 of a multi-task contract to further enhance concrete filled FRP : tubes, or the Bridge in a Backpack. Task 2 is an investigation of alternative shapes for the FRP tubes with varying : radii. Task ...

Spirit's Airbags Leave Trail

NASA Technical Reports Server (NTRS)

2004-01-01

The smooth surfaces of angular and rounded rocks seen in this image of the martian terrain may be the result of wind-polishing debris. The picture was taken by the panoramic camera on the Mars Exploration Rover Spirit.

Research on Aerodynamic Characteristics of Composite powered Unmanned Airship

NASA Astrophysics Data System (ADS)

Chen, Yu; Wang, Yun; Wang, Lu; Ma, Chengyu; Xia, Jun

2017-10-01

The main structure of the composite powered unmanned airship is consists of airbags and four-rotor system, which airbag increases the available lift, and has more advantages in terms of load and flight when compared with the traditional four-rotor. In order to compare the aerodynamic performance of the composite powered unmanned airship and the traditional four-rotor, the SIMPLE algorithm and the RNG k-epsilon model method are be used. The energy consumption of the composite powered unmanned airship is lesser than the traditional four-rotor under the same load and range was found.

Bridge-in-a-Backpack(TM) task 3.1: investigating soil - structure interaction - experimental design.

DOT National Transportation Integrated Search

2015-07-01

This report includes fulfillment of Task 3.1 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 3 is an investigation of soil-structure interaction for the FRP tubes. Task 3.1 is the : design of...

Evaluation of Eco-Efficiency and Performance of Retrofit Materials

NASA Astrophysics Data System (ADS)

Gopinath, Smitha; Rama Chandra Murthy, A.; Iyer, Nagesh R.; Kokila, S.

2015-12-01

In this work three materials namely Fiber Reinforced Polymer (FRP), ferrocement and Textile Reinforced Concrete (TRC) have been evaluated towards their performance efficiency and eco-effectiveness for sustainable retrofitting applications. Investigations have been carried out for flexural strengthening of RC beams with FRP, ferrocement and TRC. It is observed that in the case of FRP, it is not possible to tailor the material according to design requirements and most of the time strengthened structure becomes over stiff. Eco-effectiveness of these retrofitting materials has been evaluated by computing the embodied energy. It is observed that the amount of CO2 emitted by TRC is less compared to other retrofit materials. Further, the performance point of retrofitted RC frames has been evaluated and damage index has been calculated to find out the effective retrofit material. It is concluded that, if RC frame is retrofitted with FRP and TRC, it undergoes less damage compared to ferrocement.

Ultrasound assisted extraction of polyphenols and their distribution in whole mung bean, hull and cotyledon.

PubMed

Singh, Barinderjit; Singh, Narpinder; Thakur, Sheetal; Kaur, Amritpal

2017-03-01

In this study, extraction of polyphenols using different solvents (acetone, ethanol, methanol and water) with ultrasound and conventional method from whole mung bean (WMB), hull and cotyledon was conducted. Total phenolic content (TPC), total flavonoids content (TFC), total antioxidant activities (TAA), ferric reducing power (FRP) and DPPH radical scavenging activity were determined. Ultrasound treated extracts exhibited higher TPC, TFC, TAA, FRP and DPPH in different mung bean fractions than CSE. Among the solvents, acetone showed better TPC, TFC, TAA, FRP and DPPH. Hull had significantly higher TPC, TFC, TAA, FRP and DPPH than WMB and cotyledon. Sinapic acid (SA) was the major polyphenol in different fractions. Acetone extract of hull showed high polyphenol content. SA, ferulic acid, catechin, p-coumaric acid, resveratrol, quercetin and luteolin were the major contributors to antioxidant activity of acetone extract. Mung bean hull contained the maximum polyphenols and acetone was observed to be the best extraction medium for polyphenols in combination with ultrasound.

Use of pultruded reinforced plastics in energy generation and energy related applications

NASA Astrophysics Data System (ADS)

Anderson, R.

Applications of pultrusion-formed fiber-reinforced plastics (FRP) in the wind, oil, and coal derived energy industries are reviewed. FRP is noted to be a viable alternative to wood, aluminum, and steel for reasons of availability, price, and weight. Attention is given to the development of FRP wind turbine blades for the DOE 8 kW low cost, high reliability wind turbine program. The blades feature a NACA 23112 profile with a 15 in. chord on the system which was tested at Rocky Flats, CO. Fabricating the blades involved a plus and minus 45 deg roving orientation, a heavy fiber-glass nose piece to assure blade strength, and a separately manufactured foam core. Additional uses for FRP products have been found in the structural members of coal stack scrubbers using a vinyl ester resin in a fire retardant formulation, and as low cost, light weight sucker rods for deep well oil drilling.

SIRT1 suppresses adipogenesis by activating Wnt/β-catenin signaling in vivo and in vitro

PubMed Central

Zhou, Yuanfei; Song, Tongxing; Peng, Jie; Zhou, Zheng; Wei, Hongkui; Zhou, Rui; Jiang, Siwen; Peng, Jian

2016-01-01

Sirtuin 1 (SIRT1) regulates adipocyte and osteoblast differentiation. However, the underlying mechanism should be investigated. This study revealed that SIRT1 acts as a crucial repressor of adipogenesis. RNA-interference-mediated SIRT1 knockdown or genetic ablation enhances adipogenic potential, whereas SIRT1 overexpression inhibits adipogenesis in mesenchymal stem cells (MSCs). SIRT1 also deacetylates the histones of sFRP1, sFRP2, and Dact1 promoters; inhibits the mRNA expression of sFRP1, sFRP2, and Dact1; activates Wnt signaling pathways; and suppresses adipogenesis. SIRT1 deacetylates β-catenin to promote its accumulation in the nucleus and thus induces the transcription of genes that block MSC adipogenesis. In mice, the partial absence of SIRT1 promotes the formation of white adipose tissues without affecting the development of the body of mice. Our study described the regulatory role of SIRT1 in Wnt signaling and proposed a regulatory mechanism of adipogenesis. PMID:27776347

Does Classification of Chronic Musculoskeletal Disorder Patients Into Psychosocial Subgroups Predict Differential Treatment Responsiveness and 1-Year Outcomes After a Functional Restoration Program?

PubMed

Asih, Sali; Mayer, Tom G; Williams, Mark; Choi, Yun Hee; Gatchel, Robert J

2015-12-01

The objectives of this study: (1) to assess whether Multidimensional Pain Inventory (MPI) profiles predicted differential responses to a functional restoration program (FRP) in chronic disabling occupational musculoskeletal disorder (CDOMD) patients; (2) to examine whether coping style improves following FRP; and (3) to determine whether discharge MPI profiles predict discharge psychosocial and 1-year socioeconomic outcomes. Consecutive CDOMD patients (N=716) were classified into Adaptive Coper (AC, n=209), Interpersonally Distressed (ID, n=154), Dysfunctional (DYS, n=310), and Anomalous (n=43) using the MPI, and reclassified at discharge. Profiles were compared on psychosocial measures and 1-year socioeconomic outcomes. An intent-to-treat sample analyzed the effect of drop-outs on treatment responsiveness. The MPI classification significantly predicted program completion (P=0.001), although the intent-to-treat analyses found no significant effects of drop-out on treatment responsiveness. There was a significant increase in the number of patients who became AC or Anomalous at FRP discharge and a decrease in those who were ID or DYS. Patients who changed or remained as DYS at FRP discharge reported the highest levels of pain, disability, and depression. No significant interaction effect was found between MPI group and time for pain intensity or disability. All groups improved on psychosocial measures at discharge. DYS patients had decreased work retention and a greater health care utilization at 1 year. An FRP was clinically effective for CDOMD patients regardless of initial MPI profiles. The FRP modified profiles, with patients changing from negative to positive profiles. Discharge DYS were more likely to have poor 1-year outcomes. Those classified as Anomalous had a good prognosis for functional recovery similar to ACs.

The Structure, Design, and Closed-Loop Motion Control of a Differential Drive Soft Robot.

PubMed

Wu, Pang; Jiangbei, Wang; Yanqiong, Fei

2018-02-01

This article presents the structure, design, and motion control of an inchworm inspired pneumatic soft robot, which can perform differential movement. This robot mainly consists of two columns of pneumatic multi-airbags (actuators), one sensor, one baseboard, front feet, and rear feet. According to the different inflation time of left and right actuators, the robot can perform both linear and turning movements. The actuators of this robot are composed of multiple airbags, and the design of the airbags is analyzed. To deal with the nonlinear performance of the soft robot, we use radial basis function neural networks to train the turning ability of this robot on three different surfaces and create a mathematical model among coefficient of friction, deflection angle, and inflation time. Then, we establish the closed-loop automatic control model using three-axis electronic compass sensor. Finally, the automatic control model is verified by linear and turning movement experiments. According to the experiment, the robot can finish the linear and turning movements under the closed-loop control system.

Numerical analysis of interface debonding detection in bonded repair with Rayleigh waves

NASA Astrophysics Data System (ADS)

Xu, Ying; Li, BingCheng; Lu, Miaomiao

2017-01-01

This paper studied how to use the variation of the dispersion curves of Rayleigh wave group velocity to detect interfacial debonding damage between FRP plate and steel beam. Since FRP strengthened steel beam is two layers medium, Rayleigh wave velocity dispersion phenomenon will happen. The interface debonding damage of FRP strengthened steel beam have an obvious effect on the Rayleigh wave velocity dispersion curve. The paper first put forward average Euclidean distance and Angle separation degree to describe the relationship between the different dispersion curves. Numerical results indicate that there is a approximate linear mapping relationship between the average Euclidean distance of dispersion curves and the length of interfacial debonding damage.

Biomass Combustions and Burning Emissions Inferred from GOES Fire Radiative Power

NASA Astrophysics Data System (ADS)

Zhang, X.; Kondragunta, S.; Schmidt, C.

2007-12-01

Biomass burning significantly affects air quality and climate changes. Current estimates of burning emissions are rather imprecise and vary markedly with different methodologies. This paper investigates biomass burning consumption and emissions using GOES (Geostationary Operational Environmental Satellites) WF_ABBA (Wildfire Automated Biomass Burning Algorithm) fire product. In doing this, we establish a set of representatives in diurnal patterns of half-hourly GOES Fire Radiative Power (FRP) for various ecosystems. The representative patterns are used to fill the missed and poor observations of half hourly FRP in GOES fire data for individual fire pixels. The simulated FRP is directly applied to the calculation of the biomass combusted during fire activities. The FRP-based biomass combustion is evaluated using the estimates using a traditional model which integrates burned area, fuel loading, and combustion factor. In the traditional model calculation, we derive burned areas from GOES WF_ABBA fire size. Fuel loading includes three different types (1) MODIS Vegetation Property-based Fuel System (MVPFS), (2) National Dangerous Rating Systems (NFDRS), and (3) the Fuel Characteristic Classification System (FCCS). By comparing the biomass combustions across the Contiguous United States (CONUS) from 2003-2005, we conclude that FRP is an effective tool to estimate the biomass burning emissions. Finally, we examine the temporal and spatial patterns in biomass combustions and emissions (PM2.5, CO, NH3) across the CONUS.

In-process, non-destructive multimodal dynamic testing of high-speed composite rotors

NASA Astrophysics Data System (ADS)

Kuschmierz, Robert; Filippatos, Angelos; Langkamp, Albert; Hufenbach, Werner; Czarske, Jürgern W.; Fischer, Andreas

2014-03-01

Fibre reinforced plastic (FRP) rotors are lightweight and offer great perspectives in high-speed applications such as turbo machinery. Currently, novel rotor structures and materials are investigated for the purpose of increasing machine efficiency, lifetime and loading limits. Due to complex rotor structures, high anisotropy and non-linear behavior of FRP under dynamic loads, an in-process measurement system is necessary to monitor and to investigate the evolution of damages under real operation conditions. A non-invasive, optical laser Doppler distance sensor measurement system is applied to determine the biaxial deformation of a bladed FRP rotor with micron uncertainty as well as the tangential blade vibrations at surface speeds above 300 m/s. The laser Doppler distance sensor is applicable under vacuum conditions. Measurements at varying loading conditions are used to determine elastic and plastic deformations. Furthermore they allow to determine hysteresis, fatigue, Eigenfrequency shifts and loading limits. The deformation measurements show a highly anisotropic and nonlinear behavior and offer a deeper understanding of the damage evolution in FRP rotors. The experimental results are used to validate and to calibrate a simulation model of the deformation. The simulation combines finite element analysis and a damage mechanics model. The combination of simulation and measurement system enables the monitoring and prediction of damage evolutions of FRP rotors in process.

Design and control of a novel gastroscope intervention mechanism with circumferentially pneumatic-driven clamping function.

PubMed

Li, Yanmin; Liu, Hao; Hao, Siwen; Li, Hongyi; Han, Jianda; Yang, Yunsheng

2017-03-01

Robot-assisted manipulation is promising for solving problems such as understaffing and the risk of infection in gastro-intestinal endoscopy. However, the commonly used friction rollers in few existing systems have a potential risk of deforming flexible endoscopes for non-uniform clamping. This paper presents a robotic system for a standard flexible endoscope and focuses on a novel gastroscope intervention mechanism (GIM), which provides circumferentially uniform clamping with an airbag. The GIM works with a relay-on mechanism in a way similar to manual operation. The shear stiffness of airbag and the critical slipping force (CSF) were analysed to determine the parameters of the airbag. A fuzzy PID controller was employed to realize a fast response and high accuracy of pneumatic actuation. Experiments were performed to evaluate the accuracy, stiffness and CSF. In vitro and in vivo animal experiments were also carried out. The GIM realized an accuracy of 0.025 ± 0.2 mm and -0.03 ± 0.25° for push-pull and rotation without delivery resistance. Under < 10 N delivery resistance, the error caused by the airbag stiffness was < 0.24 mm. A quadratic polynomial could be used to describe the relationship between the CSF and pneumatic pressure. The novel GIM could effectively deliver gastroscopes. The pneumatic-driven clamping method proposed could protect the gastroscope by circumferentially uniform clamping force and the CSF could be properly controlled to guarantee operating safety. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Induction of CXC chemokines in human mesenchymal stem cells by stimulation with secreted frizzled-related proteins through non-canonical Wnt signaling.

PubMed

Bischoff, David S; Zhu, Jian-Hua; Makhijani, Nalini S; Yamaguchi, Dean T

2015-12-26

To investigate the effect of secreted frizzled-related proteins (sFRPs) on CXC chemokine expression in human mesenchymal stem cells (hMSCs). CXC chemokines such as CXCL5 and CXCL8 are induced in hMSCs during differentiation with osteogenic differentiation medium (OGM) and may be involved in angiogenic stimulation during bone repair. hMSCs were treated with conditioned medium (CM) from L-cells expressing non-canonical Wnt5a protein, or with control CM from wild type L-cells, or directly with sFRPs for up to 10 d in culture. mRNA expression levels of both CXCL5 and CXCL8 were quantitated by real-time reverse transcriptase-polymerase chain reaction and secreted protein levels of these proteins determined by ELISA. Dose- (0-500 ng/mL) and time-response curves were generated for treatment with sFRP1. Signal transduction pathways were explored by western blot analysis with pan- or phosphorylation-specific antibodies, through use of specific pathway inhibitors, and through use of siRNAs targeting specific frizzled receptors (Fzd)-2 and 5 or the receptor tyrosine kinase-like orphan receptor-2 (RoR2) prior to treatment with sFRPs. CM from L-cells expressing Wnt5a, a non-canonical Wnt, stimulated an increase in CXCL5 mRNA expression and protein secretion in comparison to control L-cell CM. sFRP1, which should inhibit both canonical and non-canonical Wnt signaling, surprisingly enhanced the expression of CXCL5 at 7 and 10 d. Dickkopf1, an inhibitor of canonical Wnt signaling prevented the sFRP-stimulated induction of CXCL5 and actually inhibited basal levels of CXCL5 expression at 7 but not at 10 d post treatment. In addition, all four sFRPs isoforms induced CXCL8 expression in a dose- and time-dependent manner with maximum expression at 7 d with treatment at 150 ng/mL. The largest increases in CXCL5 expression were seen from stimulation with sFRP1 or sFRP2. Analysis of mitogen-activated protein kinase signaling pathways in the presence of OGM showed sFRP1-induced

Induction of CXC chemokines in human mesenchymal stem cells by stimulation with secreted frizzled-related proteins through non-canonical Wnt signaling

PubMed Central

Bischoff, David S; Zhu, Jian-Hua; Makhijani, Nalini S; Yamaguchi, Dean T

2015-01-01

AIM: To investigate the effect of secreted frizzled-related proteins (sFRPs) on CXC chemokine expression in human mesenchymal stem cells (hMSCs). METHODS: CXC chemokines such as CXCL5 and CXCL8 are induced in hMSCs during differentiation with osteogenic differentiation medium (OGM) and may be involved in angiogenic stimulation during bone repair. hMSCs were treated with conditioned medium (CM) from L-cells expressing non-canonical Wnt5a protein, or with control CM from wild type L-cells, or directly with sFRPs for up to 10 d in culture. mRNA expression levels of both CXCL5 and CXCL8 were quantitated by real-time reverse transcriptase-polymerase chain reaction and secreted protein levels of these proteins determined by ELISA. Dose- (0-500 ng/mL) and time-response curves were generated for treatment with sFRP1. Signal transduction pathways were explored by western blot analysis with pan- or phosphorylation-specific antibodies, through use of specific pathway inhibitors, and through use of siRNAs targeting specific frizzled receptors (Fzd)-2 and 5 or the receptor tyrosine kinase-like orphan receptor-2 (RoR2) prior to treatment with sFRPs. RESULTS: CM from L-cells expressing Wnt5a, a non-canonical Wnt, stimulated an increase in CXCL5 mRNA expression and protein secretion in comparison to control L-cell CM. sFRP1, which should inhibit both canonical and non-canonical Wnt signaling, surprisingly enhanced the expression of CXCL5 at 7 and 10 d. Dickkopf1, an inhibitor of canonical Wnt signaling prevented the sFRP-stimulated induction of CXCL5 and actually inhibited basal levels of CXCL5 expression at 7 but not at 10 d post treatment. In addition, all four sFRPs isoforms induced CXCL8 expression in a dose- and time-dependent manner with maximum expression at 7 d with treatment at 150 ng/mL. The largest increases in CXCL5 expression were seen from stimulation with sFRP1 or sFRP2. Analysis of mitogen-activated protein kinase signaling pathways in the presence of OGM showed sFRP

An Overview of the New FEER Smoke Emissions Product and Its Applications over Northern Sub-Saharan Africa

NASA Astrophysics Data System (ADS)

Ellison, L. T.; Ichoku, C. M.

2012-12-01

A new smoke emissions inventory is being derived by NASA's Fire Energetics and Emissions Research (FEER, http://feer.gsfc.nasa.gov/) group in conjunction with the NASA-funded interdisciplinary research project on the interactions and feedbacks between biomass burning and water cycle dynamics across the Northern Sub-Saharan African (NSSA) region. The vast amount of anthropogenic biomass burning conducted in NSSA during the dry months contributes significant amounts of gaseous and particulate emissions to the local climate system. The emissions product presented here is a result of the efforts made to utilize quantitative satellite measures of important fire and smoke variables to generate an accurate emissions product that can be used to quantify the relationship between biomass burning and regional climate impacts. This new product is based on a unique top-down approach whereby radiant energy and emission rates are related from independent yet coincident remotely sensed retrievals of fire radiative power (FRP) and aerosol optical depth (AOD) from the two active Moderate Resolution Imaging Spectroradiometer (MODIS) instruments. The algorithm produces a 1×1° global grid of coefficients of emission, Ce, that directly relate FRP to emission rates, or equivalently, fire radiative energy (FRE, the temporally integrated FRP curve) to emissions. Thus, emissions can be easily and quickly obtained in a given region by multiplying the Ce grid with FRP measurements acquired within that region. The Ce product offers the user flexibility in using any desired FRP data source, and the lag time in generating emissions is only constrained by that of obtaining FRP. The accuracy of this emissions product and its comparisons to other established emissions databases are presented here, as is a discussion of the contribution that this product will make toward accounting for climate variabilities in the NSSA region.

Laboratory and field performance of FOS sensors in static and dynamic strain monitoring in concrete bridge decks

NASA Astrophysics Data System (ADS)

Benmokrane, B.; Debaiky, A.; El-Ragaby, A.; Roy, R.; El-Gamal, S.; El-Salakawy, E.

2006-03-01

There is a growing need for designing and constructing innovative concrete bridges using FRP reinforcing bars as internal reinforcement to avoid the corrosion problems and high costs of maintenance and repair. For efficient use and to increase the lifetime of these bridges, it is important to develop efficient monitoring systems for such innovative structures. Fabry-Perot and Bragg fibre optic sensors (FOS) that can measure the strains and temperature are promising candidates for life-long health monitoring of these structures. This article reports laboratory and field performance of Fabry-Perot and Bragg FOS sensors as well as electrical strain gauges in static and dynamic strain monitoring in concrete bridge decks. The laboratory tests include tensile testing of glass FRP bars and testing of full-scale concrete bridge deck slabs reinforced with glass and carbon FRP bars under static and cyclic concentrated loads. The field tests include static and dynamic testing of two bridges reinforced with steel and glass FRP bars. The obtained strain results showed satisfactory agreement between the different gauges.

An Analysis of Interfacial Stresses in Steel Beams Bonded With a Thin Composite Plate Under Thermomechanical Loading

NASA Astrophysics Data System (ADS)

Benyoucef, S.; Tounsi, A.; Yeghnem, R.; Bachir Bouiadjra, M.; Adda Bedia, E. A.

2014-01-01

The strengthening of steel structures in situ with externally bonded fiber-reinforced plastic (FRP) composite sheets is increasingly being used for the repair and rehabilitation of existing structures. The previous researchers have developed several analytical methods to predict the interface performance of bonded repairs. An important feature of a reinforced steel beam is the significant stress concentration in the adhesive at the ends of the FRP plate. In this paper, a closed-form solution for the interfacial shear and normal stresses in simply supported steel beams strengthened with a bonded FRP plate and subjected to thermomechanical loadings is presented. The shear strains of the adherends are included in the present theoretical analysis by assuming a parabolic distribution of shear stress across their thickness. Contrary to some existing studies, the assumption that both adherends have the same curvature is not used in the present study. The results of this numerical study are beneficial for understanding the mechanical behavior of material interfaces and for the design of hybrid FRP-reinforced steel structures.

Fluid shifts during thermal stress with and without fluid replacement

NASA Technical Reports Server (NTRS)

Myhre, L. G.; Robinson, S.

1977-01-01

Six unacclimatized men rested for 4 hr in a hot, dry environment without fluid replacement (DH). Another group of six men were exposed to the same thermal stress, replacing evaporative fluid loss with warm 0.1% NaCl solution (FRP). Total grams of circulating hemoglobin, determined by CO immediately prior to and again during the last minutes of heat exposure, increased an insignificant 1.6 and 1.3% during DH and FRP, respectively. With DH, body weight loss of 2.6% was accompanied by a 7.8% reduction in calculated plasma volume (PV). Even when body weight was maintained (FRP), PV decreased 2.9% during the heat exposure. Total circulating serum protein did not change as a result of the heat stress with either DH or FRP. In a test-retest series of experiments on four men, DH was not detrimental to sweat rate. It is shown that hemodilution is not a general response to acute heat exposure. The disproportionately large reduction in PV during thermal dehydration is confirmed.