WorldWideScience

Sample records for ultralight aircraft crashes

  1. Load event: Aircraft crash

    International Nuclear Information System (INIS)

    Fritsch, H.

    1985-01-01

    The bibliography includes 48 quotations, up to the year 1983, on the following issues: Experiments and computational methods. Design load for the dimensioning of reinforced concrete buildings and components with respect to the dynamic load in the event of an aircraft crash. (orig./HP) [de

  2. Use of ultralight aircraft for introducing migratory crane populations

    Science.gov (United States)

    Clegg, K.R.; Lewis, J.C.; Ellis, D.H.; Urbanek, Richard P.; Stahlecker, Dale

    1997-01-01

    Objectives were to determine if captive-reared cranes could be led behind an ultralight aircraft (UL) along a migration route and, if after release on a wintering area, they would integrate with wild cranes and migrate north in spring to their natal area without assistance. Greater sandhill cranes (Grus canadensis tabida) were used as the research surrogate for whooping cranes (Grus americana). In 1995, the senior author raised 15 cranes to fledging and trained them to respond to his vocal imitation of a sandhill crane brood call. Chicks learned to follow him as he walked, drove an all-terrain vehicle (ATV), or piloted an UL. The caretakers were not in crane costumes. Cranes were tame but allowed to roam at will without accompanying humans part of the day and were penned at night. Daily excursions provided exposure to habitats, foods, and predators the birds would encounter after release into the wild. In mid-October 1995, 11 radio-tagged cranes were led in migration from Grade, Idaho to Bosque del Apache National Wildlife Refuge (BdANWR), central New Mexico, and released near wild wintering sandhill cranes. The 1,204km migration took 11 days, including 1 day when the aircraft were grounded due to a winter storm. Hazards encountered enroute included mountainous terrain, turbulent air, and attacks by gold eagles (Aquila chrysaetos). On the wintering ground, hazards included crane hunters and coyotes (Canis latrans). Within 2 days after release at the BdANWR wintering site, the research cranes were associating with and imitating the behavior of wild cranes. The 4 surviving birds migrated north in spring 1996 and at the time of this writing 2 were within 53 km of their natal area in Idaho.

  3. Teaching migration routes to canada geese and trumpeter swans using ultralight aircraft, 1990-2001

    Science.gov (United States)

    Sladen, William J. L.; Lishman, W.A.; Ellis, D.H.; Shire, G.G.; Rininger, D.L.; Rees, Eileen C.; Earnst, Susan L.; Coulson, John C.

    2002-01-01

    This paper summarizes eleven years (1990-2001) of experiments to teach Canada Geese (Branta canadensis) and Trumpeter Swans (Cygnus buccinator) pre-selected migration routes using ultralight aircraft. When Canada Geese were trained to follow an ultralight aircraft for southward autumn migrations of 680 or 1,320 km, 81% (83/103) returned on their own in the next spring to near their place of training. In contrast, none returned of 21 similarly raised geese that were transported south in a closed truck over a route of 680 km. Trumpeter Swans have proven more difficult to train. However, in two experiments in which Trumpeter Swans followed an ultralight for the entire pre-selected route, one of three and two of four returned close to their training area. A stage-by-stage method, in which swans were transported in trucks between stops, flown in the vicinity and penned with a view of the night sky, has shown some promise. So far an established migration route (north and south twice) has been confirmed in only two geese

  4. Analysis of Aircraft Crash Accident for WETF

    International Nuclear Information System (INIS)

    Jordan, Hans

    2001-01-01

    This report applies the methodology of DOE-STD-3014-96, ''Accident Analysis for Aircraft Crash into Hazardous Facilities'', to the Weapons Engineering Tritium Facility (WETF) at LANL. Straightforward application of that methodology shows that including local helicopter flights with those of all other aircraft with potential to impact the facility poses a facility impact risk slightly in excess of the DOE standard's threshold--10 -6 impacts per year. It is also shown that helicopters can penetrate the facility if their engines impact that facility's roof. However, a refinement of the helicopter impact analysis shows that penetration risk of the facility for all aircraft lies below the DOE standard's threshold. By that standard, therefore, the potential for release of hazardous material from the facility as a result of an aircraft crashing into the facility is negligible and need not be analyzed further

  5. Graphene-Based Ultra-Light Batteries for Aircraft

    Science.gov (United States)

    Calle, Carlos I.; Kaner, Richard B.

    2014-01-01

    Develop a graphene-based ultracapacitor prototype that is flexible, thin, lightweight, durable, low cost, and safe and that will demonstrate the feasibility for use in aircraft center dot These graphene-based devices store charge on graphene sheets and take advantage of the large accessible surface area of graphene (2,600 m2/g) to increase the electrical energy that can be stored. center dot The proposed devices should have the electrical storage capacity of thin-film-ion batteries but with much shorter charge/discharge cycle times as well as longer lives center dot The proposed devices will be carbon-based and so will not have the same issues with flammability or toxicity as the standard lithium-based storage cells There are two main established methods for the storage and delivery of electrical energy: center dot Batteries - Store energy with electrochemical reactions - High energy densities - Slow charge/discharge cycles - Used in applications requiring large amounts of energy ? aircraft center dot Electrochemical capacitors - Store energy in electrochemical double layers - Fast charge/discharge cycles - Low energy densities - Used in electronics devices - Large capacitors are used in truck engine cranking

  6. Offsite radiological consequence analysis for the bounding aircraft crash accident

    International Nuclear Information System (INIS)

    OBERG, B.D.

    2003-01-01

    The purpose of this calculation note is to quantitatively analyze a bounding aircraft crash accident for comparison to the DOE-STD-3009-94, ''Preparation Guide for U.S. Department of Energy Nonreactor Nuclear Facility Documented Safety Analyses'', Appendix A, Evaluation Guideline of 25 rem. The potential of aircraft impacting a facility was evaluated using the approach given in DOE-STD-3014-96, ''Accident Analysis for Aircraft Crash into Hazardous Facilities''. The following aircraft crash FR-equencies were determined for the Tank Farms in RPP-11736, ''Assessment Of Aircraft Crash FR-equency For The Hanford Site 200 Area Tank Farms'': (1) The total aircraft crash FR-equency is ''extremely unlikely.'' (2) The general aviation crash FR-equency is ''extremely unlikely.'' (3) The helicopter crash FR-equency is ''beyond extremely unlikely.'' (4) For the Hanford Site 200 Areas, other aircraft type, commercial or military, each above ground facility, and any other type of underground facility is ''beyond extremely unlikely.'' As the potential of aircraft crash into the 200 Area tank farms is more FR-equent than ''beyond extremely unlikely,'' consequence analysis of the aircraft crash is required

  7. DOAS measurements of NO2 from an ultralight aircraft during the Earth Challenge expedition

    Directory of Open Access Journals (Sweden)

    O. Ronveaux

    2012-08-01

    Full Text Available We report on airborne Differential Optical Absorption Spectroscopy (DOAS measurements of NO2 tropospheric columns above South Asia, the Arabic peninsula, North Africa, and Italy in November and December 2009. The DOAS instrument was installed on an ultralight aircraft involved in the Earth Challenge project, an expedition of seven pilots flying on four ultralight aircraft between Australia and Belgium. The instrument recorded spectra in limb geometry with a large field of view, a set-up which provides a high sensitivity to the boundary layer NO2 while minimizing the uncertainties related to the attitude variations. We compare our measurements with OMI (Ozone Monitoring Instrument and GOME-2 (Global Ozone Monitoring Experiment 2 tropospheric NO2 products when the latter are available. Above Rajasthan and the Po Valley, two areas where the NO2 field is homogeneous, data sets agree very well. Our measurements in these areas are 0.1 ± 0.1 to 3 ± 1 × 1015 molec cm−2 and 2.6 ± 0.8 × 1016 molec cm−2, respectively. Flying downwind of Riyadh, our NO2 measurements show the structure of the megacity's exhaust plume with a higher spatial resolution than OMI. Moreover, our measurements are larger (up to 40% than those seen by satellites. We also derived tropospheric columns when no satellite data were available if it was possible to get information on the visibility from satellite measurements of aerosol optical thickness. This experiment also provides a confirmation for the recent finding of a soil signature above desert.

  8. Numerical analyses of an aircraft crash on containment building

    Energy Technology Data Exchange (ETDEWEB)

    Sim, Jae Min; Kim, Seung Hyun; Chang, Yoon Suk [Kyunghee University, Yongin (Korea, Republic of)

    2016-05-15

    The containment building is responsible to isolate and protect internal devices against external conditions like earthquake, hurricane and impact loading. It has also to protect leakage of radioactivity, like LOCA (Loss Of Coolant Accident), when severe accidents occurred. Meanwhile, social awareness such as terrorism has been increased globally after international aircraft crashes at World Trade Center and Pentagon. In this paper, FE (Finite Element) analyses according to variation of crash locations and speeds were carried out to examine the aircraft crash impact on a domestic containment building. In this paper, numerical analyses of aircraft crash on NPP's containment building were performed taking into account different locations and aircraft speeds. (1) Amounts of concrete failure were dependent on the crash locations and the connector was the most delicate location comparing to the dome and wall part. (2) Maximum stress values generated at the liner plate and rebars did not exceed their UTS values.

  9. Numerical analyses of an aircraft crash on containment building

    International Nuclear Information System (INIS)

    Sim, Jae Min; Kim, Seung Hyun; Chang, Yoon Suk

    2016-01-01

    The containment building is responsible to isolate and protect internal devices against external conditions like earthquake, hurricane and impact loading. It has also to protect leakage of radioactivity, like LOCA (Loss Of Coolant Accident), when severe accidents occurred. Meanwhile, social awareness such as terrorism has been increased globally after international aircraft crashes at World Trade Center and Pentagon. In this paper, FE (Finite Element) analyses according to variation of crash locations and speeds were carried out to examine the aircraft crash impact on a domestic containment building. In this paper, numerical analyses of aircraft crash on NPP's containment building were performed taking into account different locations and aircraft speeds. (1) Amounts of concrete failure were dependent on the crash locations and the connector was the most delicate location comparing to the dome and wall part. (2) Maximum stress values generated at the liner plate and rebars did not exceed their UTS values

  10. Improvement of Aircraft Crash Effective Areas for Koeberg Nuclear Power Plant

    International Nuclear Information System (INIS)

    Momoti, S.; Dongmo, G.B.; Combrink, Y.

    2017-01-01

    Probabilistic Safety Assessment (PSA): Tool for determining safe functioning of nuclear power plant to meet regulatory requirements; One of the inputs to the PSA are the frequency and consequences of an aircraft crash. Overview: Frequency of Aircraft Crash; Effective Area of an Aircraft Crashing into Koeberg - Aviation Categories, - Shielding of sensitive target buildings; Impact of refining the Effective AreaFrequency of Aircraft Crash

  11. Structural Integrity Assessment of Reactor Containment Subjected to Aircraft Crash

    International Nuclear Information System (INIS)

    Kim, Junyong; Chang, Yoonsuk

    2013-01-01

    When an accident occurs at the NPP, containment building which acts as the last barrier should be assessed and analyzed structural integrity by internal loading or external loading. On many occasions that can occur in the containment internal such as LOCA(Loss Of Coolant Accident) are already reflected to design. Likewise, there are several kinds of accidents that may occur from the outside of containment such as earthquakes, hurricanes and strong wind. However, aircraft crash that at outside of containment is not reflected yet in domestic because NPP sites have been selected based on the probabilistic method. After intentional aircraft crash such as World Trade Center and Pentagon accident in US, social awareness for safety of infrastructure like NPP was raised world widely and it is time for assessment of aircraft crash in domestic. The object of this paper is assessment of reactor containment subjected to aircraft crash by FEM(Finite Element Method). In this paper, assessment of structural integrity of containment building subjected to certain aircraft crash was carried out. Verification of structure integrity of containment by intentional severe accident. Maximum stress 61.21MPa of horizontal shell crash does not penetrate containment. Research for more realistic results needed by steel reinforced concrete model

  12. Accident analysis for aircraft crash into hazardous facilities: DOE standard

    International Nuclear Information System (INIS)

    1996-10-01

    This standard provides the user with sufficient information to evaluate and assess the significance of aircraft crash risk on facility safety without expending excessive effort where it is not required. It establishes an approach for performing a conservative analysis of the risk posed by a release of hazardous radioactive or chemical material resulting from an aircraft crash into a facility containing significant quantities of such material. This can establish whether a facility has a significant potential for an aircraft impact and whether this has the potential for producing significant offsite or onsite consequences. General implementation guidance, screening and evaluation guidelines, and methodologies for the evaluations are included

  13. Aircraft crash upon outer containment of nuclear power plant

    International Nuclear Information System (INIS)

    Abbas, H.; Paul, D.K.; Godbole, P.N.; Nayak, G.C.

    1996-01-01

    In this paper, analysis of an aircraft crash upon an outer containment of a nuclear power plant is presented. The effect of target yielding is considered simultaneously by calculating the reaction time in a time marching scheme. The concrete model employed is capable of predicting the cracking and yielding. The response for different cracking strains and different locations of aircraft strike for different aircraft has been studied. Critical location of aircraft strike for the containment has been investigated. The analytical procedure and the material model used are found to be capable of representing the aircraft impact response of the containment structure. (orig.)

  14. Advances in crash dynamics for aircraft safety

    Science.gov (United States)

    Guida, M.; Marulo, F.; Abrate, S.

    2018-04-01

    This paper studies the ability of the fuselage's lower lobe to absorb the energy during a crash landing, where the introduction of the composite materials can improve the crash survivability thanks to the crushing capability of structural parts to limit the effects of deceleration on the occupants. Providing a protective shell around the occupants and minimizing the risks of injuries during and immediately after the crash in the post-crash regime is a safety requirement. This study consists of: (1) numerical and experimental investigations on small components to verify design concepts using high performance composite materials; (2) analyses of full scale crashes of fuselage lower lobes. This paper outlines an approach for demonstrating the crashworthiness characteristics of the airframe performing a drop test at low velocity impact to validate a numerical model obtained by assembling structural components and materials' properties previously obtained by testing coupons and sub-elements.

  15. Aircraft-crash-protected roof design for the European SBWR

    International Nuclear Information System (INIS)

    Posta, B.A.; Kadar, I.; Rao, A.S.

    1995-01-01

    The European utility requirement document (EURD) places significant emphasis on aircraft crash protection of the reactor building - Alternative concepts were evaluated for protecting the dry-well head and the fuel pool from the effect of the spalling concrete for the General Electric Company's European simplified boiling water reactor (ESBWR) designs

  16. Information note about the protection of nuclear facilities against aircraft crashes

    International Nuclear Information System (INIS)

    2001-01-01

    The protection of nuclear facilities against external risks (earthquakes, floods, fires etc..) is an aspect of safety taken into consideration by the French authority of nuclear safety (ASN). Concerning the aircraft crashes, the fundamental safety rules make three categories of aircraft: the small civil aircraft (weight 5.7 t). Nuclear facilities are designed to resist against crashes of aircraft from the first category only, because the probability of the accidental crash of a big aircraft are extremely low. This document comprises an information note about the protection of nuclear facilities against aircraft crashes, a dossier about the safety of nuclear facilities with respect to external risks in general (natural disasters and aircraft crashes), and an article about the protection of nuclear power plants against aircraft crashes (design, safety measures, regulation, surveillance, experience feedback). (J.S.)

  17. Damage assessment of nuclear containment against aircraft crash

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Mohd Ashraf, E-mail: iqbal_ashraf@rediffmail.com; Sadique, Md. Rehan, E-mail: rehan.sadique@gmail.com; Bhargava, Pradeep, E-mail: bhpdpfce@iitr.ac.in; Bhandari, N.M., E-mail: nmbcefce@iitr.ac.in

    2014-10-15

    Highlights: • Damage assessment of nuclear containment is studied against aircraft crash. • Four impact locations have been identified at the outer containment shell. • The mid of the total height has been found to be most vulnerable location. • The crown of dome has been found to be the strongest location. • Phantom F4 caused more localized and severe damage compared to other aircrafts. - Abstract: The behavior of nuclear containment structure has been studied against aircraft crash with an emphasis on the influence of strike location. The impact locations identified on the BWR Mark III type nuclear containment structure are mid-height, junction of dome and cylinder, crown of dome and arc of dome. The containment at each of the above locations has been impacted normally by Phantom F-4, Boeing 707-320 and Airbus A320 aircrafts. The loading of the aircraft has been assigned through the corresponding reaction-time response curve. ABAQUS/Explicit finite element code has been used to carry out the three-dimensional numerical simulations. The concrete damaged plasticity model was used to simulate the behavior of concrete while the behavior of steel reinforcement was incorporated using the Johnson–Cook elasto-viscoplastic material model. The mid-height of containment has been found to experience most severe deformation against each aircraft. Phantom F4 has been found to be most disastrous at each location. The results have been compared with those of the available studies with respect to the containment deformation.

  18. Aircraft crash survivability from viscous injury in vertical impacts

    OpenAIRE

    Barth, Thomas H.

    2009-01-01

    This research investigated viscous injury from vertical impact loading to determine if it is critical to survivability of aircraft accidents. A unique database was built from autopsy reports and accident investigations combining injury data with the vehicle impact data. Computer models were created and used to assess injury potential. Common design limits and actual crash data from full scale research experiments were used as inputs. The results were analyzed according to publi...

  19. Nuclear containment structure subjected to commercial and fighter aircraft crash

    International Nuclear Information System (INIS)

    Sadique, M.R.; Iqbal, M.A.; Bhargava, P.

    2013-01-01

    Highlights: • Nuclear containment response has been studied against aircraft crash. • Concrete damaged plasticity and Johnson–Cook elasto-viscoplastic models were employed. • Boeing 747-400 and Boeing 767-400 aircrafts caused global failure of containment. • Airbus A320 and Boeing 707-320 aircrafts caused local damage. • Tension damage of concrete was found more prominent compared to compression damage. -- Abstract: The response of a boiling water reactor (BWR) nuclear containment vessel has been studied against commercial and fighter aircraft crash using a nonlinear finite element code ABAQUS. The aircrafts employed were Boeing 747-400, Boeing 767-400, Airbus A-320, Boeing 707-320 and Phantom F4. The containment was modeled as a three-dimensional deformable reinforced concrete structure while the loading of aircraft was assigned using the respective reaction–time curve. The location of strike was considered near the junction of dome and cylinder, and the angle of incidence, normal to the containment surface. The material behavior of the concrete was incorporated using the damaged plasticity model while that of the reinforcement, the Johnson–Cook elasto-viscoplastic model. The containment could not sustain the impact of Boeing 747-400 and Boeing 767-400 aircrafts and suffered rupture of concrete around the impact region leading to global failure. On the other hand, the maximum local deformation at the point of impact was found to be 0.998 m, 0.099 m, 0.092 m, 0.089 m, and 0.074 m against Boeing 747-400, Phantom F4, Boeing 767, Boeing 707-320 and Airbus A-320 aircrafts respectively. The results of the present study were compared with those of the previous analytical and numerical investigations with respect to the maximum deformation and overall behavior of the containment

  20. Nuclear containment structure subjected to commercial and fighter aircraft crash

    Energy Technology Data Exchange (ETDEWEB)

    Sadique, M.R., E-mail: rehan.sadique@gmail.com; Iqbal, M.A., E-mail: iqbalfce@iitr.ernet.in; Bhargava, P., E-mail: bhpdpfce@iitr.ernet.in

    2013-07-15

    Highlights: • Nuclear containment response has been studied against aircraft crash. • Concrete damaged plasticity and Johnson–Cook elasto-viscoplastic models were employed. • Boeing 747-400 and Boeing 767-400 aircrafts caused global failure of containment. • Airbus A320 and Boeing 707-320 aircrafts caused local damage. • Tension damage of concrete was found more prominent compared to compression damage. -- Abstract: The response of a boiling water reactor (BWR) nuclear containment vessel has been studied against commercial and fighter aircraft crash using a nonlinear finite element code ABAQUS. The aircrafts employed were Boeing 747-400, Boeing 767-400, Airbus A-320, Boeing 707-320 and Phantom F4. The containment was modeled as a three-dimensional deformable reinforced concrete structure while the loading of aircraft was assigned using the respective reaction–time curve. The location of strike was considered near the junction of dome and cylinder, and the angle of incidence, normal to the containment surface. The material behavior of the concrete was incorporated using the damaged plasticity model while that of the reinforcement, the Johnson–Cook elasto-viscoplastic model. The containment could not sustain the impact of Boeing 747-400 and Boeing 767-400 aircrafts and suffered rupture of concrete around the impact region leading to global failure. On the other hand, the maximum local deformation at the point of impact was found to be 0.998 m, 0.099 m, 0.092 m, 0.089 m, and 0.074 m against Boeing 747-400, Phantom F4, Boeing 767, Boeing 707-320 and Airbus A-320 aircrafts respectively. The results of the present study were compared with those of the previous analytical and numerical investigations with respect to the maximum deformation and overall behavior of the containment.

  1. Assessment procedure and probability determination methods of aircraft crash events in siting for nuclear power plants

    International Nuclear Information System (INIS)

    Zheng Qiyan; Zhang Lijun; Huang Weiqi; Yin Qingliao

    2010-01-01

    Assessment procedure of aircraft crash events in siting for nuclear power plants, and the methods of probability determination in two different stages of prelimi- nary screening and detailed evaluation are introduced in this paper. Except for general air traffic, airport operations and aircraft in the corridor, the probability of aircraft crash by military operation in the military airspaces is considered here. (authors)

  2. Aircraft Crash Survival Design Guide. Volume 5. Aircraft Postcrash Survival

    Science.gov (United States)

    1980-01-01

    neck Access door toprille capm enrFuel tank Figue 3. Fangblefiler eckinsalgbelati n. A-j L)n wal Aircraft skin Frangible filler neck Failure plane...This is because a number of major assumptions must be made in the extrapolation: the smoke generated is uniformly distri- buted and is independent

  3. Numerical simulation of aircraft crash on nuclear containment structure

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, M.A., E-mail: iqbalfce@iitr.ernet.in [Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee 247667 (India); Rai, S.; Sadique, M.R.; Bhargava, P. [Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee 247667 (India)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer The deformation was more localised at the center of cylindrical portion. Black-Right-Pointing-Pointer The peak deflection at the junction of dome and cylinder was found to be 67 mm. Black-Right-Pointing-Pointer The peak deflection at midpoint of the cylindrical portion was found to be 88.9 mm. Black-Right-Pointing-Pointer The strain rate was found to be an important parameter to effect the deformation. Black-Right-Pointing-Pointer The model without strain rate and 290 s{sup -1} strain rate predicted very high deformations. - Abstract: Numerical simulations were carried with ABAQUS/Explicit finite element code in order to predict the response of BWR Mark III type nuclear containment against Boeing 707-320 aircraft crash. The load of the aircraft was applied using and force history curve. The damaged plasticity model was used to predict the behavior of concrete while the Johnson-Cook elasto-viscoplastic material model was used to incorporate the behavior of steel reinforcement. The crash was considered to occur at two different locations i.e., the midpoint of the cylindrical portion and the junction of dome and cylinder. The midpoint of the cylindrical portion experienced more deformation. The strain rate in the material model was varied and found to have a significant effect on the response of containment. The results of the present investigation were compared with those of the studies available in literature and a close agreement with the previous results was found in terms of maximum target deformation.

  4. Safety Assessment of a Metal Cask under Aircraft Engine Crash

    Directory of Open Access Journals (Sweden)

    Sanghoon Lee

    2016-04-01

    Full Text Available The structural integrity of a dual-purpose metal cask currently under development by the Korea Radioactive Waste Agency (KORAD was evaluated, through numerical simulations and a model test, under high-speed missile impact reflecting targeted aircraft crash conditions. The impact conditions were carefully chosen through a survey on accident cases and recommendations from literature. In the impact scenario, a missile flying horizontally hits the top side of the cask, which is freestanding on a concrete pad, with a velocity of 150 m/s. A simplified missile simulating a commercial aircraft engine was designed from an impact load–time function available in literature. In the analyses, the dynamic behavior of the metal cask and the integrity of the containment boundary were assessed. The simulation results were compared with the test results for a 1:3 scale model. Although the dynamic behavior of the cask in the model test did not match exactly with the prediction from the numerical simulation, other structural responses, such as the acceleration and strain history during the impact, showed very good agreement. Moreover, the containment function of the cask survived the missile impact as expected from the numerical simulation. Thus, the procedure and methodology adopted in the structural numerical analyses were successfully validated.

  5. Aircraft crash protection from a military engineering point of view

    International Nuclear Information System (INIS)

    Lynch, J.P.

    1975-01-01

    The general problem is to investigate the situation of an aircraft crash on a reactor building. One aspect of the problem is to determine if the structural conditions required to protect the environment against the results of an impact at the center of a 10 m by 10 m reinforced concrete wall slab are reasonable. This paper discusses the dynamic structural response problem, using the analytical methods developed for military structures designed to resist blast loading. The military protection problem is quite similar to reactor protection in that extensive analysis is required to define the threat or loading conditions. The post-dynamic-loading structural requirements must also be defined, since every possible source of resistance is used to obtain a structure which protects against the stated threat at the lowest cost. Such a structural design contains the lowest possible factor of safety, using reasonable analytical techniques, and is more properly called collapse design. If more protection is provided than required, the cost will be greater than necessary. An aircraft jet engine impact is selected as the loading condition for the protection requirements of the reactor wall panel. Analytical investigation of the impact indicates that the load function can be reasonably well approximated by the half sine wave pressure-time curve. Thus, the maximum pressure and duration of the half sine pressure pulse completely define the load-time history. (orig./HP) [de

  6. Regulatory Analysis on the Safety Assessment of NPPs against Aircraft Crash

    International Nuclear Information System (INIS)

    Kim, Sang Yun; Park, Jong Seuk; Chung, Yun Suk; Jung, Rae Young

    2011-01-01

    Following the 9/11 terror, a new regulation (10CFR 50.150) was enacted in June 2009 in the United States mandating the assessment of new nuclear power plants (NPPs) against intentional aircraft crashes, along with a regulation (10CFR 50.54 (h)(h)) in March 2009 that requires the establishment of accident mitigation measures for NPPs in operation. The UAE requested that the Korean NPP (APR 1400) design meet the U.S.'s new requirements related to the intentional aircraft crash. During the UAE NPP contract bidding process, France claimed that the Korean NPP is vulnerable to aircraft crashes comparing with the French NPP (EPR). Under these international and domestic environments, the necessity to establish a domestic regulation concerning the intentional aircraft crash was raised. This paper proposes a draft regulatory position on this issue through a comprehensive analysis of various influencing factors

  7. Vertical profile of aerosols in the Himalayan region using an ultralight aircraft platform

    Science.gov (United States)

    Singh, A.; Mahata, K.; Rupakheti, M.; Lawrence, M. G.; Junkermann, W.

    2017-12-01

    Indo-gangetic plain (IGP) and Himalayan foothills have large spatial and temporal heterogeneity in aerosols characteristics. Regional meteorology around 850-500 mb plays an important role in the transformation and transportation of aerosols from west Asia to IGP, into Himalayan foothill, as well to high-altitude region of the Himalayas. In order to quantify the vertical and horizontal variation of aerosol properties in the Himalayan , an airborne campaign was carried out in the Pokhara Valley/Nepal (83°50'-84°10' E, 25°7'-28°15' N, 815 masl ) in two phases: test flights during May 2016 and an intensive airborne sampling flight in December-January 2017. This paper provides an overview of airborne measurement campaign from the first phase of measurements in May 2016. A two-seater microlight aircraft (IKARUS C 42) was used as the aerial platform. This was deemed the feasible option in Nepal for an aerial campaign; technical specification of the aircraft include an approximately 6 hrs of flying time, short-take off run, > 100 kgs of payload, suitable for spiral upward and downward profiling. The instrument package consist of GRIMM 1.108 for particle size distribution from 0.3 to 20 um at 6 seconds time resolution, and TSI CPC 3375 for total ultrafine particle (UFP) concentration at 1 s. The package also includes a Magee Scientific Aethalometer (AE42) for aerosol absorption at seven different wavelengths. Meteorological parameters include temperature and dew point at a sampling rate of 1 Hz or higher. The paper provides a snapshot of observed vertical profile (from 800 to 4500masl) of aerosols size, number and black carbon over one of populated mountain valley in Nepal during the pre-monsoon season. During the airborne measurement, local fires- mostly agriculture burn were observed, however no large scale forest fire was captured. Sharp morning and afternoon gradients were observed in the vertical profile for aerosol number and size, mostly dominated by 2000 masl

  8. Data development technical support document for the aircraft crash risk analysis methodology (ACRAM) standard

    International Nuclear Information System (INIS)

    Kimura, C.Y.; Glaser, R.E.; Mensing, R.W.; Lin, T.; Haley, T.A.; Barto, A.B.; Stutzke, M.A.

    1996-01-01

    The Aircraft Crash Risk Analysis Methodology (ACRAM) Panel has been formed by the US Department of Energy Office of Defense Programs (DOE/DP) for the purpose of developing a standard methodology for determining the risk from aircraft crashes onto DOE ground facilities. In order to accomplish this goal, the ACRAM panel has been divided into four teams, the data development team, the model evaluation team, the structural analysis team, and the consequence team. Each team, consisting of at least one member of the ACRAM plus additional DOE and DOE contractor personnel, specializes in the development of the methodology assigned to that team. This report documents the work performed by the data development team and provides the technical basis for the data used by the ACRAM Standard for determining the aircraft crash frequency. This report should be used to provide the generic data needed to calculate the aircraft crash frequency into the facility under consideration as part of the process for determining the aircraft crash risk to ground facilities as given by the DOE Standard Aircraft Crash Risk Assessment Methodology (ACRAM). Some broad guidance is presented on how to obtain the needed site-specific and facility specific data but this data is not provided by this document

  9. Design of the crashworthy structure of an urban aircraft

    Directory of Open Access Journals (Sweden)

    Shang Bairong

    2017-01-01

    Full Text Available With the development of general aviation, the urban aircraft is around the corner. The urban aircraft with composite is considered as an ultralight vehicle and the crashworthiness is of vital importance for such an ultralight aircraft. Composites are being widely and increasingly used in the aerospace industry because of their advantages that include the high specific strength and stiffness over traditional metallic materials. Besides, composites have the potential for absorbing the energy in a crash event. The crashworthiness of the cockpit section is analyzed in this paper and some modifications in the subfloor have been made to improve the survivability of the pilot. Advances in commercial softwares have enabled engineers to simulate crash events. The three-dimensional structure model is established by use of CATIA software and the crash process is simulated by MSC/DYTRAN. By comparing the crashworthiness of composite structures, reliable basis is provided for the design of a safe and sound structure.

  10. Information note about the protection of nuclear facilities against aircraft crashes; Note d'information sur la protection des installations nucleaires contre les chutes d'avions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The protection of nuclear facilities against external risks (earthquakes, floods, fires etc..) is an aspect of safety taken into consideration by the French authority of nuclear safety (ASN). Concerning the aircraft crashes, the fundamental safety rules make three categories of aircraft: the small civil aircraft (weight < 5.7 t), the military aircraft, and the commercial aircraft (w > 5.7 t). Nuclear facilities are designed to resist against crashes of aircraft from the first category only, because the probability of the accidental crash of a big aircraft are extremely low. This document comprises an information note about the protection of nuclear facilities against aircraft crashes, a dossier about the safety of nuclear facilities with respect to external risks in general (natural disasters and aircraft crashes), and an article about the protection of nuclear power plants against aircraft crashes (design, safety measures, regulation, surveillance, experience feedback). (J.S.)

  11. REPAIR TECHNOLOGY OF THE COMPOSITE WING OF A LIGHT PLANE DAMAGED DURING AN AIRCRAFT CRASH

    Directory of Open Access Journals (Sweden)

    Andrzej ŚWIĄTONIOWSKI

    2016-09-01

    Full Text Available The increasing use of composite structures in aircraft constructions has made it necessary to develop repair methods that will restore the component’s original design strength without compromising its structural integrity. In this paper, the complex repair technology of the composite wing of a light plane, which was damaged during an aircraft crash, is described. The applied repair scheme should meet all the original design requirements for the plane structure.

  12. Classification of soft and hard impacts-Application to aircraft crash

    International Nuclear Information System (INIS)

    Koechlin, Pierre; Potapov, Serguei

    2009-01-01

    Before modeling an aircraft crash on a shield building of a nuclear power plant, it is very important to understand the physical phenomena and the structural behavior associated with this kind of impact. In the scientific literature, aircraft crash is classified as a soft impact, or as an impact of deformable missile. Nevertheless the existing classifications are not precise enough to be able to predict 'a priori' the structural response mode. The aim of this paper is to characterize very precisely what is a soft and a hard impact in the frame of aircraft crash on nuclear power plant. First the existing qualitative definition of soft and hard impact is quickly reviewed in order to introduce a new criterion to make a quantitative distinction between soft and hard impact. Then the experimental tests carried out during the last thirty years in the research field of aircraft crash are presented in the light of the new classification. The authors show that this characterization of soft and hard impacts has a real physical interest because it is linked to the failure mode for perforation: for soft impacts, perforation is the consequence of a shear plug breaking away and for hard impact it comes from local failure and projectile penetration. Moreover the boundary between soft and hard impact is the limit for the use of an impact force in an uncoupled computation of the impact

  13. Particulate Characterization and Control Evaluation for Carbon Fiber Composite Aircraft Crash Recovery Operations

    Science.gov (United States)

    2010-03-01

    Advanced Composite Office, Wright-Patterson BEE Flight, and USAFSAM for their help procuring the materials and supplies needed to perform this study...that would occur during an aircraft crash. The JP-8 was then 26 ignited with a butane lighter and allowed to burn to extinction . A burning ACM

  14. Factors associated with pilot fatality in work-related aircraft crashes, Alaska, 1990-1999.

    Science.gov (United States)

    Bensyl, D M; Moran, K; Conway, G A

    2001-12-01

    Work-related aircraft crashes are the leading cause of occupational fatality in Alaska, with civilian pilots having the highest fatality rate (410/100,000/year). To identify factors affecting survivability, the authors examined work-related aircraft crashes that occurred in Alaska in the 1990s (1990-1999), comparing crashes with pilot fatalities to crashes in which the pilot survived. Using data from National Transportation Safety Board reports, the authors carried out logistic regression analysis with the following variables: age, flight experience, use of a shoulder restraint, weather conditions (visual flight vs. instrument flight), light conditions (daylight vs. darkness), type of aircraft (airplane vs. helicopter), postcrash fire, crash location (airport vs. elsewhere), and state of residence. In the main-effects model, significant associations were found between fatality and postcrash fire (adjusted odds ratio (AOR) = 6.43, 95% confidence interval (CI): 2.38, 17.37), poor weather (AOR = 4.11, 95% CI: 2.15, 7.87), and non-Alaska resident status (AOR = 2.10, 95% CI: 1.05, 4.20). Protective effects were seen for shoulder restraint use (AOR = 0.40, 95% CI: 0.21, 0.77) and daylight versus darkness (AOR = 0.50, 95% CI: 0.25, 0.99). The finding that state of residence was associated with survivability offers new information on pilot survivability in work-related aircraft crashes in Alaska. These results may be useful in targeting safety interventions for pilots who fly occupationally in Alaska or in similar environments.

  15. Estimate of aircraft crash hit frequencies on to facilities at the Lawrence Livermore National Laboratory (LLNL) Site 200

    International Nuclear Information System (INIS)

    Kimura, C.Y.

    1997-01-01

    Department of Energy (DOE) nuclear facilities are required by DOE Order 5480.23, Section 8.b.(3)(k) to consider external events as initiating events to accidents within the scope of their Safety Analysis Reports (SAR). One of the external initiating events which should be considered within the scope of a SAR is an aircraft accident, i.e., an aircraft crashing into the nuclear facility with the related impact and fire leading to penetration of the facility and to the release of radioactive and/or hazardous materials. This report presents the results of an Aircraft Crash Frequency analysis performed for the Materials Management Area (MMA), and the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) Site 200. The analysis estimates only the aircraft crash hit frequency on to the analyzed facilities. No initial aircraft crash hit frequency screening structural response calculations of the facilities to the aircraft impact, or consequence analysis of radioactive/hazardous materials released following the aircraft impact are performed. The method used to estimate the aircraft crash hit frequencies on to facilities at the Lawrence Livermore National Laboratory (LLNL) generally follows the procedure given by the DOE Standard 3014-96 on Aircraft Crash Analysis. However, certain adjustments were made to the DOE Standard procedure because of the site specific fight environment or because of facility specific characteristics

  16. Cirrus Airframe Parachute System and Odds of a Fatal Accident in Cirrus Aircraft Crashes.

    Science.gov (United States)

    Alaziz, Mustafa; Stolfi, Adrienne; Olson, Dean M

    2017-06-01

    General aviation (GA) accidents have continued to demonstrate high fatality rates. Recently, ballistic parachute recovery systems (BPRS) have been introduced as a safety feature in some GA aircraft. This study evaluates the effectiveness and associated factors of the Cirrus Airframe Parachute System (CAPS) at reducing the odds of a fatal accident in Cirrus aircraft crashes. Publicly available Cirrus aircraft crash reports were obtained from the National Transportation Safety Board (NTSB) database for the period of January 1, 2001-December 31, 2016. Accident metrics were evaluated through univariate and multivariate analyses regarding odds of a fatal accident and use of the parachute system. Included in the study were 268 accidents. For CAPS nondeployed accidents, 82 of 211 (38.9%) were fatal as compared to 8 of 57 (14.0%) for CAPS deployed accidents. After controlling for all other factors, the adjusted odds ratio for a fatal accident when CAPS was not deployed was 13.1. The substantial increased odds of a fatal accident when CAPS was not deployed demonstrated the effectiveness of CAPS at providing protection of occupants during an accident. Injuries were shifted from fatal to serious or minor with the use of CAPS and postcrash fires were significantly reduced. These results suggest that BPRS could play a significant role in the next major advance in improving GA accident survival.Alaziz M, Stolfi A, Olson DM. Cirrus Airframe Parachute System and odds of a fatal accident in Cirrus aircraft crashes. Aerosp Med Hum Perform. 2017; 88(6):556-564.

  17. Aircraft crash upon a containment structure of a nuclear power plant

    International Nuclear Information System (INIS)

    Paul, D.K.; Abbas, H.; Godbole, P.N.; Nayak, G.C.

    1993-01-01

    The reinforced concrete outer containment of a Nuclear Power Plant (NPP) is required to be designed to withstand the impact of aircraft and aircrash debris etc. The problem is of strategic significance because the damage caused to the structure by these missiles may lead to the leakage of nuclear radiations. The safety design of NPP against aircraft crash requires the evaluation of crash probability. If the probability is smaller than the allowable value then the aircraft crash is neglected as design basis item. Otherwise adequate measures are taken to bring the released radioactive material within the permissible limit. The aircrafts and their striking velocity to be considered in the design of a structure are decided by the accident analysis. The probabilistic aspect of the problem has not been covered in the present work. The non-affordability of coupled analysis of large problems like aircraft crash on NPP, automobile impact on a structure etc. due to the requirement of excessive amount of manual as well as computer time and storage compels us to switch over to the uncoupled analysis. Moreover, the results of coupled analysis are heavily influenced by the analyst's modelling technique and choice of increment size. It is uncoupling of the missile and the target which converts the impact load to the impulse load. This impulse can be found by taking into consideration only the inertial and stiffness properties of missile and considering the target to be rigid. Though the impulse load so obtained disregards the inertial and stiffness characteristics of the target but its effect can be incorporated by modifying it for the inertial and stiffness properties of target at different time steps as we march in time domain during the analysis of the target

  18. Aircraft-crash-protected steel reactor building roof structure for the European market

    International Nuclear Information System (INIS)

    Posta, B.A.; Kadar, I.; Rao, A.S.

    1996-01-01

    This paper recommends the use of all steel roof structures for the reactor building of European Boiling Water Reactor (BWR) plants. This change would make the advanced US BWR designs more compatible with European requirements. Replacement of the existing concrete roof slab with a sufficiently thick steel plate would eliminate the concrete spelling resulting from a postulated aircraft crash, potentially damaging the drywell head or the spent fuel pool

  19. Two-leaf wall structures under 'soft' impact load - aircraft crash

    International Nuclear Information System (INIS)

    Eibl, J.; Block, K.

    1982-01-01

    The article describes a mechanical model with which the load conditions associated with aircraft crash on a two-leaf wall or roof structure can be analysed quite simply. The necessary assumptions for the material behaviour governing the contact of the two slabs and, in general, the maximum limit deformations of reinforced concrete slabs are more particularly dealt with. Treating the problem the authors make use, inter alia, of some of their own experimental results. (orig.)

  20. Assessment of the probability of an aircraft accidentally crashing on a nuclear power station

    International Nuclear Information System (INIS)

    Gravero; Lezer; Lucenet

    1975-01-01

    The probability of an accidental aircraft crash on a power station not situated near a commercial airport is assessed. Three major points in the general analysis of the problem are developed: analysis of accidents as a function of the phase of the flight and in particular during a flight in transit and examin-ation of aircraft crash conditions to determine the angle of impact on the reactor building for example; determination of the apparent surface of buildings allowing for several parameters: geometry of the building and of the aircraft, geography of the site, relative position of the buildings; assessment of air traffic above the region for the year under consideration distinguishing the weight of the aircraft which implies an investigation of the problem for commercial aviation on the one hand (regular or irregular flights, inter-national or internal) and for general aviation on the other hand. The analysis is determined for the years 1980 - 2000 so that ir will be necessary to extrapolate some of the parameters (development of air traffic, safety of transport, etc). (author)

  1. An overview of the crash dynamics failure behavior of metal and composite aircraft structures

    Science.gov (United States)

    Carden, Huey D.; Boitnott, Richard L.; Fasanella, Edwin L.; Jones, Lisa E.

    1991-01-01

    An overview of failure behavior results is presented from some of the crash dynamics research conducted with concepts of aircraft elements and substructure not necessarily designed or optimized for energy absorption or crash loading considerations. Experimental and analytical data are presented that indicate some general trends in the failure behavior of a class of composite structures that includes fuselage panels, individual fuselage sections, fuselage frames, skeleton subfloors with stringers and floor beams without skin covering, and subfloors with skin added to the frame stringer structure. Although the behavior is complex, a strong similarity in the static/dynamic failure behavior among these structures is illustrated through photographs of the experimental results and through analytical data of generic composite structural models.

  2. Evaluation of aircraft crash at Laboratorio de Geracao Nucleo-Eletrica (LABGENE) located at Centro Experimental ARAMAR

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, Daniel M.; Ramos, Monique M.B., E-mail: daniel.hirata@ctmsp.mar.mil.br, E-mail: monique@ctmsp.mar.mil.br [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), SP (Brazil)

    2013-07-01

    One of the human-induced external hazards to be considered in a Level 1 Probabilistic Safety Assessment for a nuclear plant is the aircraft crash, so it's necessary to have the estimative of the frequency of this hazard. In this paper is obtained the annual frequency of aircraft crash at the Laboratorio de Geracao Nucleo-Eletrica (LABGENE) located at the Centro Experimental ARAMAR (CEA).The calculation of this frequency was based on the method recommended in the Standard Review Plan Section 3.5.1.6 considering the airports, training camps and airways located in CEA's region. The estimated value for the aircraft crash frequency obtained is in accordance with the acceptance criteria established in the Standard Review plan Section 3.5.1.6. (author)

  3. A METHOD FOR DETERMINING THE RADIALLY-AVERAGED EFFECTIVE IMPACT AREA FOR AN AIRCRAFT CRASH INTO A STRUCTURE

    Energy Technology Data Exchange (ETDEWEB)

    Walker, William C. [ORNL

    2018-02-01

    This report presents a methodology for deriving the equations which can be used for calculating the radially-averaged effective impact area for a theoretical aircraft crash into a structure. Conventionally, a maximum effective impact area has been used in calculating the probability of an aircraft crash into a structure. Whereas the maximum effective impact area is specific to a single direction of flight, the radially-averaged effective impact area takes into consideration the real life random nature of the direction of flight with respect to a structure. Since the radially-averaged effective impact area is less than the maximum effective impact area, the resulting calculated probability of an aircraft crash into a structure is reduced.

  4. Evaluation of aircraft crash at Laboratorio de Geracao Nucleo-Eletrica (LABGENE) located at Centro Experimental ARAMAR

    International Nuclear Information System (INIS)

    Hirata, Daniel M.; Ramos, Monique M.B.

    2013-01-01

    One of the human-induced external hazards to be considered in a Level 1 Probabilistic Safety Assessment for a nuclear plant is the aircraft crash, so it's necessary to have the estimative of the frequency of this hazard. In this paper is obtained the annual frequency of aircraft crash at the Laboratorio de Geracao Nucleo-Eletrica (LABGENE) located at the Centro Experimental ARAMAR (CEA).The calculation of this frequency was based on the method recommended in the Standard Review Plan Section 3.5.1.6 considering the airports, training camps and airways located in CEA's region. The estimated value for the aircraft crash frequency obtained is in accordance with the acceptance criteria established in the Standard Review plan Section 3.5.1.6. (author)

  5. Instrument Failure, Stress, and Spatial Disorientation Leading to a Fatal Crash With a Large Aircraft.

    Science.gov (United States)

    Tribukait, Arne; Eiken, Ola

    2017-11-01

    An aircraft's orientation relative to the ground cannot be perceived via the sense of balance or the somatosensory system. When devoid of external visual references, the pilot must rely on instruments. A sudden unexpected instrument indication is a challenge to the pilot, who might have to question the instrument instead of responding with the controls. In this case report we analyze, from a human-factors perspective, how a limited instrument failure led to a fatal accident. During straight-ahead level flight in darkness, at 33,000 ft, the commander of a civil cargo airplane was suddenly confronted by an erroneous pitch-up indication on his primary flight display. He responded by pushing the control column forward, making a bunt maneuver with reduced/negative Gz during approximately 15 s. The pilots did not communicate rationally or cross-check instruments. Recordings of elevator and aileron positions suggest that the commander made intense efforts to correct for several extreme and erroneous roll and pitch indications. Gz displayed an increasing trend with rapid fluctuations and peaks of approximately 3 G. After 50 s the aircraft entered a turn with decreasing radius and finally hit the ground in an inverted attitude. A precipitate maneuvring response can, even if occurring in a large aircraft at high altitude, result in a seemingly inexorable course of events, ending with a crash. In the present case both pilots were probably incapacitated by acute psychological stress and spatial disorientation. Intense variations in Gz may have impaired the copilot's reading of the functioning primary flight display.Tribukait A, Eiken O. Instrument failure, stress, and spatial disorientation leading to a fatal crash with a large aircraft. Aerosp Med Hum Perform. 2017; 88(11):1043-1048.

  6. Ultralight metallic microlattices.

    Science.gov (United States)

    Schaedler, T A; Jacobsen, A J; Torrents, A; Sorensen, A E; Lian, J; Greer, J R; Valdevit, L; Carter, W B

    2011-11-18

    Ultralight (nickel plating, and subsequently etching away the template. The resulting metallic microlattices exhibit densities ρ ≥ 0.9 milligram per cubic centimeter, complete recovery after compression exceeding 50% strain, and energy absorption similar to elastomers. Young's modulus E scales with density as E ~ ρ(2), in contrast to the E ~ ρ(3) scaling observed for ultralight aerogels and carbon nanotube foams with stochastic architecture. We attribute these properties to structural hierarchy at the nanometer, micrometer, and millimeter scales.

  7. Preliminary Study on Effect of Aviation Fuel in the Safety Evaluation of Nuclear Power Plant Crashed by Aircraft

    International Nuclear Information System (INIS)

    Jin, Byeong Moo; Jeon, Se Jin; Lee, Yun Seok; Kim, Young Jin

    2011-01-01

    As the safety assessments of nuclear power plants for the hypothetical large civil aircraft crash should be made mandatory, studies on large aircraft-nuclear power plant impact analyses and assessments are actively in progress. The large civil aircraft are being operated with a large amount of fuel and the fuel can be assumed to contribute to the impact loads at the impact. The fuel, i.e., the internal liquid can be considered as added masses classically in the evaluation of the impact load. According to the recent experimental research, it has been shown that the impact load of high speed impacting body with internal liquid is much higher than that of the mass-equivalent impacting body. In this study, the impact loads according to the existence of the internal liquid are computed by numerical methods and the safety assessment of nuclear power plant crashed by large civil aircraft are performed as an application

  8. Prospect of ultralight airplanes development

    Directory of Open Access Journals (Sweden)

    Adam KONICZEK

    2015-09-01

    Full Text Available The article presents characteristic of ultralight airplanes, rules and current interest of them. The purpose is to determine prospect of ultralight airplanes development on the basis of Civil Aviation Authority statistics analysis and trend of aviation market.

  9. Information note about the protection of nuclear facilities against aircraft crashes; Note d'information sur la protection des installations nucleaires contre les chutes d'avions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The protection of nuclear facilities against external risks (earthquakes, floods, fires etc..) is an aspect of safety taken into consideration by the French authority of nuclear safety (ASN). Concerning the aircraft crashes, the fundamental safety rules make three categories of aircraft: the small civil aircraft (weight < 5.7 t), the military aircraft, and the commercial aircraft (w > 5.7 t). Nuclear facilities are designed to resist against crashes of aircraft from the first category only, because the probability of the accidental crash of a big aircraft are extremely low. This document comprises an information note about the protection of nuclear facilities against aircraft crashes, a dossier about the safety of nuclear facilities with respect to external risks in general (natural disasters and aircraft crashes), and an article about the protection of nuclear power plants against aircraft crashes (design, safety measures, regulation, surveillance, experience feedback). (J.S.)

  10. A consideration of hazards, earthquakes, aircraft crashes, explosions and fires in the safety of laboratories and plants

    International Nuclear Information System (INIS)

    Doumenc, A.; Faure, J.; Mohammadioun, B.; Jacquet, P.

    1987-03-01

    Although laboratories and plants differ from nuclear reactors both in their characteristics and sitings, safety measures developed for the hazards of earthquakes, aircraft crashes, explosions and fires are very similar. These measures provide a satisfactory level of safety for these installations [fr

  11. Safety Analysis of Dual Purpose Metal Cask Subjected to Impulsive Loads due to Aircraft Engine Crash

    Science.gov (United States)

    Shirai, Koji; Namba, Kosuke; Saegusa, Toshiari

    In Japan, the first Interim Storage Facility of spent nuclear fuel away from reactor site is being planned to start its commercial operation around 2010, in use of dual-purpose metal cask in the northern part of Main Japan Island. Business License Examination for safety design approval has started since March, 2007. To demonstrate the more scientific and rational performance of safety regulation activities on each phase for the first license procedure, CREPEI has executed demonstration tests with full scale casks, such as drop tests onto real targets without impact limiters(1) and seismic tests subjected to strong earthquake motions(2). Moreover, it is important to develop the knowledge for the inherent security of metal casks under extreme mechanical-impact conditions, especially for increasing interest since the terrorist attacks from 11th September 2001(3)-(6). This paper presents dynamic mechanical behavior of the metal cask lid closure system caused by direct aircraft engine crash and describes calculated results (especially, leak tightness based on relative dynamic displacements between metallic seals). Firstly, the local penetration damage of the interim storage facility building by a big passenger aircraft engine crash (diameter 2.7m, length 4.3m, weight 4.4ton, impact velocity 90m/s) has been examined. The reduced velocity is calculated by the local damage formula for concrete structure with its thickness of 70cm. The load vs. time function for this reduced velocity (60m/s) is estimated by the impact analysis using Finite Element code LS-DYNA with the full scale engine model onto a hypothetically rigid target. Secondly, as the most critical scenarios for the metal cask, two impact scenarios (horizontal impact hitting the cask and vertical impact onto the lid metallic seal system) are chosen. To consider the geometry of all bolts for two lids, the gasket reaction forces and the inner pressure of the cask cavity, the detailed three dimensional FEM models are

  12. Crash Testing and Simulation of a Cessna 172 Aircraft: Hard Landing Onto Concrete

    Science.gov (United States)

    Jackson, Karen E.; Fasanella, Edwin L.

    2016-01-01

    A full-scale crash test of a Cessna 172 aircraft was conducted at the Landing and Impact Research Facility at NASA Langley Research Center during the summer of 2015. The purpose of the test was to evaluate the performance of Emergency Locator Transmitters (ELTs) that were mounted at various locations in the aircraft and to generate impact test data for model validation. A finite element model of the aircraft was developed for execution in LSDYNA to simulate the test. Measured impact conditions were 722.4-in/s forward velocity and 276-in/s vertical velocity with a 1.5deg pitch (nose up) attitude. These conditions were intended to represent a survivable hard landing. The impact surface was concrete. During the test, the nose gear tire impacted the concrete, followed closely by impact of the main gear tires. The main landing gear spread outward, as the nose gear stroked vertically. The only fuselage contact with the impact surface was a slight impact of the rearmost portion of the lower tail. Thus, capturing the behavior of the nose and main landing gear was essential to accurately predict the response. This paper describes the model development and presents test-analysis comparisons in three categories: inertial properties, time sequence of events, and acceleration and velocity time-histories.

  13. Assessment of the fire resistance of a nuclear power plant subjected to a large commercial aircraft crash

    International Nuclear Information System (INIS)

    Jeon, Se-Jin; Jin, Byeong-Moo; Kim, Young-Jin

    2012-01-01

    Highlights: ► A procedure to assess fire resistance of structure for aircraft crash is proposed. ► Fire scenario of containment and auxiliary building is determined for aircraft crash. ► Heat transfer and thermal stress analyses are performed to obtain section forces. ► Fire endurance time is evaluated by load–moment strength interaction diagram. - Abstract: The safety assessment of infrastructures, such as a nuclear power plant, for the crash of a large commercial aircraft has been performed worldwide after the terrorism that occurred in the U.S. on September 11, 2001. The assessment, however, has mainly focused on the techniques of impact analysis. In this study, a systematic procedure to assess the fire resistance of containment and auxiliary buildings subjected to such an aircraft crash is proposed. The intensity, duration and distribution of the fire are determined based on aircraft crash analyses and characteristics of jet fuel. A three-dimensional detailed finite element model of the containment and auxiliary buildings is established and used for heat transfer and thermal stress analyses, taking into account the material properties at an elevated temperature. Section forces can then be obtained that are based on a nonlinear stress–strain relationship. The fire resistance of the structure is assessed by comparing the fire-induced section forces with the section resistance which is evaluated using the load–moment strength interaction diagram. The study addresses the problem whereby the conventional assessment that only considers the flexural behaviour is less accurate. The assessment results support the general conclusion that the nuclear power plant structures can maintain structural integrity against external fire due to their relatively thick sections. The proposed procedure can be extensively applied to evaluate the fire endurance time of any type of structure subjected to an arbitrary fire.

  14. Study on the probability of the aircraft crash at the Experimental Power Reactor (RDE) site in Puspiptek Serpong

    International Nuclear Information System (INIS)

    Yarianto Sugeng B S; Siti Alimah; June Mellawati

    2016-01-01

    With regard to RDE site licensing process, probability of aircraft crash at RDE site area of Puspiptek Serpong has been assessed. The objective of the research (assessment) is to determine the probability of occurrence of aircraft crash at the RDE site area. The methodology used in the research consist of secondary and primary data collection, identification of potential hazards sources (airports) in the vicinity of RDE site and mapping of its distribution, initial screening using a value of Screening Distance Value (SDV) and Safety Region of Flight Operations value (KKOP), as well as the calculation of the probability of the aircraft crash in the site area. The study was conducted in December 2015 - June 2016. The results showed that in the vicinity of the RDE site there are seven airports airport, namely Soekarno-Hatta (Soetta), Halim Perdanakusuma, Atang Sendjaja, Budiarto, Pondok Cabe, Rumpin and Pulau Panjang, with distances ranging from 11.72 to 79.64 km. Based on the SDV (small airport is 10 km and a large airport is 16 km), the RDE site is in outside of the airports SDV radius. However, based on KKOP (14.5 km radius), the RDE site is in inside of the two airports KKOP radius (Budiarto and Pondok Cabe). Probability calculations showed that the potential of aircraft crash in the site area of RDE coming from the Budiarto airports is 0.0066 x 10"-"7 events/year and from Pondok Cabe 0.0278 x10"-"7 events/year. The probability value was lower than the criteria based on IAEA report (10"-"7 events/year), so the RDE site categorized safe from the potential of aircraft crash. (author)

  15. Heat shields for aircraft - A new concept to save lives in crash fires.

    Science.gov (United States)

    Neel, C. B.; Parker, J. A.; Fish, R. H.; Henshaw, J.; Newland, J. H.; Tempesta, F. L.

    1971-01-01

    A passenger compartment surrounded by a fire-retardant shell, to protect the occupants long enough for the fire to burn out or for fire-fighting equipment to reach the aircraft and extinguish it, is proposed as a new concept for saving lives in crash fires. This concept is made possible by the recent development of two new fire-retardant materials: a very lightweight foam plastic, called polyisocyanurate foam, and an intumescent paint. Exposed to heat, the intumescent paint expands to many times its original thickness and insulates the surface underneath it. Demonstration tests are illustrated, described and discussed. However, some problems, such as preventing fuselage rupture and protecting windows, must be solved before such a system can be used.

  16. Reliability analysis of nuclear containment without metallic liners against jet aircraft crash

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, N.A.; Iqbal, M.A.; Abbas, H. E-mail: abbas_husain@hotmail.com; Paul, D.K

    2003-09-01

    The present study presents a methodology for detailed reliability analysis of nuclear containment without metallic liners against aircraft crash. For this purpose, a nonlinear limit state function has been derived using violation of tolerable crack width as failure criterion. This criterion has been considered as failure criterion because radioactive radiations may come out if size of crack becomes more than the tolerable crack width. The derived limit state uses the response of containment that has been obtained from a detailed dynamic analysis of nuclear containment under an impact of a large size Boeing jet aircraft. Using this response in conjunction with limit state function, the reliabilities and probabilities of failures are obtained at a number of vulnerable locations employing an efficient first-order reliability method (FORM). These values of reliability and probability of failure at various vulnerable locations are then used for the estimation of conditional and annual reliabilities of nuclear containment as a function of its location from the airport. To study the influence of the various random variables on containment reliability the sensitivity analysis has been performed. Some parametric studies have also been included to obtain the results of field and academic interest.

  17. Safety analysis of dual purpose metal cask subjected to impulsive loads due to aircraft engine crash

    International Nuclear Information System (INIS)

    Shirai, Koji; Namba, Kosuke; Saegusa, Toshiari

    2009-01-01

    In Japan, the first Interim Storage Facility of spent nuclear fuel away from reactor site is being planned to start its commercial operation around 2010, in use of dual-purpose metal cask in the northern part of Main Japan Island. Business License Examination for safety design approval has started since March, 2007. To demonstrate the more scientific and rational performance of safety regulation activities on each phase for the first license procedure, CREPEI has executed demonstration tests with full scale casks, such as drop tests onto real targets without impact limiters and seismic tests subjected to strong earthquake motions. Moreover, it is important to develop the knowledge for the inherent security of metal casks under extreme mechanical-impact conditions, especially for increasing interest since the terrorist attacks from 11th September 2001. This paper presents dynamic mechanical behavior of the metal cask lid closure system caused by direct aircraft engine crash and describes calculated results (especially, leak tightness based on relative dynamic displacements between metallic seals). Firstly, the local penetration damage of the interim storage facility building by a big passenger aircraft engine research (diameter 2.7m, length 4.3m, weight 4.4ton, impact velocity 90m/s) has been examined. The reduced velocity is calculated by the local damage formula for concrete structure with its thickness of 70cm. The load vs. time function for this reduced velocity (60m/s) is estimated by the impact analysis using Finite Element code LS-DYNA with the full scale engine model onto a hypothetically rigid target. Secondly, as the most critical scenarios for the metal cask, two impact scenarios (horizontal impact hitting the cask and vertical impact onto the lid metallic seal system) are chosen. To consider the geometry of all bolts for two lids, the gasket reaction forces and the inner pressure of the cask cavity, the detailed three dimensional FEM models are developed

  18. Non-invasive examination of a skull fragment recovered from a World War Two aircraft crash site.

    Science.gov (United States)

    Gapert, René; Rieder, Kurt

    2013-09-01

    The discovery of human remains dating to the time of the Second World War is a common occurrence in Europe and the Pacific regions. This case report demonstrates the analysis of a bone fragment recovered from a Luftwaffe crash site in Austria during the summer of 2007. Eye-witness statements and official reports were used to reconstruct the historical background of the case. A recovered German military identity tag helped to identify the pilot. Aircraft parts, also discovered at the crash site in 2007, aided the identification of the aircraft type and corroborated the eye-witness reports of the final moments before and during the crash. The bone was analyzed chiefly to establish its human or non-human origin and to identify from which anatomic region the fragment could have arisen. It was identified as part of a human adult skull which exhibited peri-mortem fractures and heat damage as well as post-mortem vegetation staining. The historical background information in connection with the morphological analysis led to the presumptive identification of the cranial fragment as belonging to a downed German pilot.

  19. Improved process for calculating the probability of being hit by crashing aircraft by the Balfanz-model

    International Nuclear Information System (INIS)

    Hennings, W.

    1988-01-01

    For calculating the probability of being hit by crashing military aircraft on different buildings, a model was introduced, which has already been used in the conventional fields. In the context of converting the research reactor BER II, this model was also used in the nuclear field. The report introduces this model and shows the application to a vertical cylinder as an example. Compared to the previous model, an exact and also simpler solution of the model attempt for determining the shade surface for different shapes of buildings is derived. The problems of the distribution of crashes given by the previous model is treated via the vertical angle and an attempt to solve these problems is given. (orig./HP) [de

  20. Structural evaluation of spent nuclear fuel storage facilities under aircraft crash impact. Numerical study on evaluation of sealing performance of metal cask subjected to impact force

    International Nuclear Information System (INIS)

    Namba, Kosuke; Shirai, Koji; Saegusa, Toshiari

    2008-01-01

    A lot of safety evaluations on the important nuclear facilities against the aircraft crash have been reported in other countries. But the condition and the evaluation method to define impact force of aircraft crash have not been described clearly in the reports. In Japan, public concern with the safety evaluation against aircraft crash is increasing. It is important to make clear the behavior of the storage facilities installing the metal casks on impact loading due to aircraft crash. In this study, concerning crash between commercial aircraft and storage facility, impact analysis using dynamic analysis code LS-DYNA has been executed. The results showed that the storage facility was not completely destroyed. But the rigid aircraft engine may penetrate into the storage facility with local failure. Thus, we assumed the engine hit a metal cask in the storage facility and evaluated sealing performance of the metal cask under the impact loading. If the engine with 90m/s crashed the storage facility having concrete wall of 85cm in thickness, the remaining velocity became 60m/s after penetration. We calculated impact force of the engine with 60m/s crashing into the metal cask. Concerning the metal cask loaded the impact force, impact analysis was executed. We assumed two directions of impact force. One is vertical load and another is horizontal load against the cask. The result showed that plastic strain was not generated on flanges of the 1st lid and the sealing performance of the cask was maintained in each impact case. (author)

  1. Ultralight particle dark matter

    International Nuclear Information System (INIS)

    Ringwald, A.

    2013-10-01

    We review the physics case for very weakly coupled ultralight particles beyond the Standard Model, in particular for axions and axion-like particles (ALPs): (i) the axionic solution of the strong CP problem and its embedding in well motivated extensions of the Standard Model; (ii) the possibility that the cold dark matter in the Universe is comprised of axions and ALPs; (iii) the ALP explanation of the anomalous transparency of the Universe for TeV photons; and (iv) the axion or ALP explanation of the anomalous energy loss of white dwarfs. Moreover, we present an overview of ongoing and near-future laboratory experiments searching for axions and ALPs: haloscopes, helioscopes, and light-shining-through-a-wall experiments.

  2. Ultralight particle dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Ringwald, A.

    2013-10-15

    We review the physics case for very weakly coupled ultralight particles beyond the Standard Model, in particular for axions and axion-like particles (ALPs): (i) the axionic solution of the strong CP problem and its embedding in well motivated extensions of the Standard Model; (ii) the possibility that the cold dark matter in the Universe is comprised of axions and ALPs; (iii) the ALP explanation of the anomalous transparency of the Universe for TeV photons; and (iv) the axion or ALP explanation of the anomalous energy loss of white dwarfs. Moreover, we present an overview of ongoing and near-future laboratory experiments searching for axions and ALPs: haloscopes, helioscopes, and light-shining-through-a-wall experiments.

  3. Structural evaluation of spent nuclear fuel storage facilities under aircraft crash impact (2). Horizontal impact test onto reduced scale metal cask due to aircraft engine missile

    International Nuclear Information System (INIS)

    Namba, Kosuke; Shirai, Koji; Saegusa, Toshiari

    2009-01-01

    In this study, to confirm the sealing performance of a metal cask subjected to impact force due to possible commercial aircraft crash against a spent fuel storage facility, the horizontal impact test was carried out. In the test, an aircraft engine missile with a speed of 57.3 m/s attacked the reduced scale metal cask containing helium gas, which stands vertically. Then the leak rate and sliding displacement of the lid were measured. The leak rate increased rapidly and reached to 4.0 x 10 -6 Pa·m 3 /sec. After that, the leak rate decreased slowly and converged to 1.0x10 -6 Pa·m 3 /sec after 20 hours from the impact test. The leak rate of a full scale cask was evaluated using that of reduced scale cask obtained by the test. Then the leak rate of the full scale cask was 3.5x10 -5 Pa·m 3 /sec. This result showed that the sealing performance of the full scale metal cask would not be affected immediately by the horizontal impact of the aircraft engine with a speed of 57.3 m/s. (author)

  4. Experimental simulation of a light aircraft crash on to a nuclear power plant auxiliary building roof

    International Nuclear Information System (INIS)

    Barnes, D.; Barr, P.; Garton, G.; Howe, W.D.; Neilson, A.J.

    1984-08-01

    The experiments described were conducted at a reduced scale with geometric dimensions of prototype structures of one-fifth full size. The target was based on the auxiliary buildings for the proposed Sizewell PWR. Descriptions of the simulated aircraft model and the test panels are given, together with the instrumentation. Details are given of the test programme and the results are summarized and discussed. Comparison is made of the model aircraft tests with an equivalent hard missile impact. (U.K.)

  5. Dynamic Response Analysis of Storage Cask Lid Structure Subjected to Lateral Impact Load of Aircraft Engine Crash

    International Nuclear Information System (INIS)

    Almomania, Belal; Kang, Hyun Gook; Lee, Sanghoon

    2015-01-01

    Several numerical methods and tests have been carried out to measure the capability of storage cask to withstand extreme impact loads. Testing methods are often constrained by cost, and difficulty in preparation for several impact conditions with different applied loads, and areas of impact. Instead, analytic method is an acceptable process that can easily apply different impact conditions for the evaluation of cask integrity. The aircraft engine impact is considered as one of the most critical impact accidents on the storage cask that significantly affects onto the lid closure system and may cause a considerable release of radioactive materials. This paper presents a method for evaluating the dynamic responses of one upper metal cask lid closure without impact limiters subjected to lateral impact of an aircraft engine with respect to variation of the impact velocity. An assessment method to predict damage response due to the lateral engine impact onto metal storage cask has been studied by using computer code LS-DYNA. The dynamic behavior of the lid movements was successfully calculated by utilizing a simplified finite element cask model, which showed a good agreement with the previous research. The simulation analyses results showed that no significant plastic deformation for bolts, lid, and the cask body. In this study, the lid opening and sliding displacements are considered as the major factors in initiating the leakage path. This analysis may be useful for evaluating the instantaneous leakage rates in a connection with the sliding and opening displacements between the lid and the flange to ensure that the radiological consequences caused by an aircraft engine crash accident during the storage phase are within the permissible level

  6. Structural analysis of a metal spent-fuel storage cask in an aircraft crash for risk assessment

    International Nuclear Information System (INIS)

    Almomani, Belal; Lee, Sanghoon; Kang, Hyun Gook

    2016-01-01

    Highlights: • Several engine-applied loads with different locations of impact on the storage cask body were implemented. • Cask structural responses due to the influence of engine impact loadings were analyzed. • Leakage path areas from lid closure openings were numerically calculated. • Release fractions that depend on the generated seal opening areas and fuel damage ratios were estimated. - Abstract: Evaluations of the impact resistance of a dry storage cask under mechanical impact loadings resulting from a large commercial aircraft crash have become an important issue for designers and evaluators, in order to promote interim dry storage activities and to evaluate design safety margins. This study presents a method to evaluate the structural integrity of a generic metal cask subjected to various mechanical loading conditions, which represent aircraft engine impacts, on different locations of the cask body. Thirty representative impact conditions are analyzed to provide a comprehensive evaluation of cask damage response. The applied engine impact load–time functions were carefully re-derived by utilizing CRIEPI’s proposed curve through Riera’s approach for six impact velocities, and applied to five locations on a freestanding cask: lateral impacts on the lower half, center of gravity, and upper half of the cask body, corner impact on the lid closure, and vertical impact on the center of the lid closure. A nonlinear dynamic finite element analysis is performed to evaluate the dynamic response of the cask lid closure system and to calculate the lid gaps. The release fractions from the cask to the environment for each impact condition are preliminarily estimated by referring to a proposed methodology from literature. It is believed that this paper presents a systematic process to connect the mechanical analysis of a cask response at the moment of aircraft engine impact with its radiological consequence analysis.

  7. Dynamic Response Analysis of Storage Cask Lid Structure Subjected to Lateral Impact Load of Aircraft Engine Crash

    Energy Technology Data Exchange (ETDEWEB)

    Almomania, Belal; Kang, Hyun Gook [KAIST, Daejeon (Korea, Republic of); Lee, Sanghoon [Keimyung Univ., Daegu (Korea, Republic of)

    2015-10-15

    Several numerical methods and tests have been carried out to measure the capability of storage cask to withstand extreme impact loads. Testing methods are often constrained by cost, and difficulty in preparation for several impact conditions with different applied loads, and areas of impact. Instead, analytic method is an acceptable process that can easily apply different impact conditions for the evaluation of cask integrity. The aircraft engine impact is considered as one of the most critical impact accidents on the storage cask that significantly affects onto the lid closure system and may cause a considerable release of radioactive materials. This paper presents a method for evaluating the dynamic responses of one upper metal cask lid closure without impact limiters subjected to lateral impact of an aircraft engine with respect to variation of the impact velocity. An assessment method to predict damage response due to the lateral engine impact onto metal storage cask has been studied by using computer code LS-DYNA. The dynamic behavior of the lid movements was successfully calculated by utilizing a simplified finite element cask model, which showed a good agreement with the previous research. The simulation analyses results showed that no significant plastic deformation for bolts, lid, and the cask body. In this study, the lid opening and sliding displacements are considered as the major factors in initiating the leakage path. This analysis may be useful for evaluating the instantaneous leakage rates in a connection with the sliding and opening displacements between the lid and the flange to ensure that the radiological consequences caused by an aircraft engine crash accident during the storage phase are within the permissible level.

  8. Structural analysis of a metal spent-fuel storage cask in an aircraft crash for risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Almomani, Belal, E-mail: balmomani@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Lee, Sanghoon, E-mail: shlee1222@kmu.ac.kr [Department of Mechanical and Automotive Engineering, Keimyung University, Dalgubeol-daero 1095, Dalseo-gu, Daegu (Korea, Republic of); Kang, Hyun Gook, E-mail: hyungook@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2016-11-15

    Highlights: • Several engine-applied loads with different locations of impact on the storage cask body were implemented. • Cask structural responses due to the influence of engine impact loadings were analyzed. • Leakage path areas from lid closure openings were numerically calculated. • Release fractions that depend on the generated seal opening areas and fuel damage ratios were estimated. - Abstract: Evaluations of the impact resistance of a dry storage cask under mechanical impact loadings resulting from a large commercial aircraft crash have become an important issue for designers and evaluators, in order to promote interim dry storage activities and to evaluate design safety margins. This study presents a method to evaluate the structural integrity of a generic metal cask subjected to various mechanical loading conditions, which represent aircraft engine impacts, on different locations of the cask body. Thirty representative impact conditions are analyzed to provide a comprehensive evaluation of cask damage response. The applied engine impact load–time functions were carefully re-derived by utilizing CRIEPI’s proposed curve through Riera’s approach for six impact velocities, and applied to five locations on a freestanding cask: lateral impacts on the lower half, center of gravity, and upper half of the cask body, corner impact on the lid closure, and vertical impact on the center of the lid closure. A nonlinear dynamic finite element analysis is performed to evaluate the dynamic response of the cask lid closure system and to calculate the lid gaps. The release fractions from the cask to the environment for each impact condition are preliminarily estimated by referring to a proposed methodology from literature. It is believed that this paper presents a systematic process to connect the mechanical analysis of a cask response at the moment of aircraft engine impact with its radiological consequence analysis.

  9. Analytical research on impacting load of aircraft crashing upon moveable concrete target

    Science.gov (United States)

    Zhu, Tong; Ou, Zhuocheng; Duan, Zhuoping; Huang, Fenglei

    2018-03-01

    The impact load of an aircraft impact upon moveable concrete target was analyzed in this paper by both theoretical and numerical methods. The aircraft was simplified as a one dimensional pole and stress-wave theory was used to deduce the new formula. Furthermore, aiming to compare with previous experimental data, a numerical calculation based on the new formula had been carried out which showed good agreement with the experimental data. The approach, a new formula with particular numerical method, can predict not only the impact load but also the deviation between moveable and static concrete target.

  10. Report 6: Guidance document. Man-made hazards and Accidental Aircraft Crash hazards modelling and implementation in extended PSA

    International Nuclear Information System (INIS)

    Kahia, S.; Brinkman, H.; Bareith, A.; Siklossy, T.; Vinot, T.; Mateescu, T.; Espargilliere, J.; Burgazzi, L.; Ivanov, I.; Bogdanov, D.; Groudev, P.; Ostapchuk, S.; Zhabin, O.; Stojka, T.; Alzbutas, R.; Kumar, M.; Nitoi, M.; Farcasiu, M.; Borysiewicz, M.; Kowal, K.; Potempski, S.

    2016-01-01

    The goal of this report is to provide guidance on practices to model man-made hazards (mainly external fires and explosions) and accidental aircraft crash hazards and implement them in extended Level 1 PSA. This report is a joint deliverable of work package 21 (WP21) and work package 22 (WP22). The general objective of WP21 is to provide guidance on all of the individual hazards selected at the first ASAMPSA-E End Users Workshop (May 2014, Uppsala, Sweden). The objective of WP22 is to provide the solutions for purposes of different parts of man-made hazards Level 1 PSA fulfilment. This guidance is focusing on man-made hazards, namely: external fires and explosions, and accidental aircraft crash hazards. Guidance developed refers to existing guidance whenever possible. The initial part of guidance (WP21 part) reflects current practices to assess the frequencies for each type of hazards or combination of hazards (including correlated hazards) as initiating event for PSAs. The sources and quality of hazard data, the elements of hazard assessment methodologies and relevant examples are discussed. Classification and criteria to properly assess hazard combinations as well as examples and methods for assessment of these combinations are included in this guidance. In appendixes additional material is presented with the examples of practical approaches to aircraft crash and man-made hazard. The following issues are addressed: 1) Hazard assessment methodologies, including issues related to hazard combinations. 2) Modelling equipment of safety related SSC, 3) HRA, 4) Emergency response, 5) Multi-unit issues. Recommendations and also limitations, gaps identified in the existing methodologies and a list of open issues are included. At all stages of this guidance and especially from an industrial end-user perspective, one must keep in mind that the development of man-made hazards probabilistic analysis must be conditioned to the ability to ultimately obtain a representative risk

  11. Structural analysis and design of a nuclear power plant building for aircraft crash effects

    International Nuclear Information System (INIS)

    Degen, P.; Furrer, H.; Jemielewski, J.

    1976-01-01

    The object of this investigation is to assess the effect of a large commercial airplane crashing perpendicularly on to the surface of a spherical reactor building dome. This investigation is related to a project currently in execution. Practical solutions of the postulated case, which vary in the degree of engineering effort used, are shown. Based on safety consideration the various solutions are discussed from the viewpoint of penetration, cracking and collapse modes of failure, where, primarily, the carrying capacity of the structure under an equivalent statical load is considered. The performed investigations include: (a) Calculation of the failure load following the yield line theory; (b) Calculation of the sectional forces using the linear-elastic shell theory and subsequent design by the ultimate strength method; (c) Calculation of the failure load, establishing of the failure mechanism and distribution of sectional forces using the plastic shell theory; (d) Calculation using a three-dimensional FEM program with plastic capabilities; this includes the collapse load, the failure mechanism and the distribution of sectional forces. A discussion of the resultant forces and the configuration of the critical section is given for the various methods used. The evaluation of the carrying capacity of the structure with respect to load is based on energy considerations. It is attempted to compare such results, to evaluate possible simplifications in the used solutions, and to give some recommendations for the practical design and for the development of structural details. (Auth.)

  12. Experiments to validate the assumptions on Pu release in an aircraft crash

    International Nuclear Information System (INIS)

    Seehars, H.D.; Hochrainer, D.

    1983-01-01

    This report describes simulation experiments with the substitute powder CeO 2 to study the release and dispersion of PuO 2 -powder induced by kerosene fires after an aeroplane crash on a Plutonium processing fuel element plant. The release rates of CeO 2 -powder were found to be a nonlinear function of te kerosene combustion rate. The release rates during a ''micro-scale'' fire inside the glovebox (pool area some 20 cm 2 ) were characterized by values of less than 10 μg/s, those during a conflagration (pool area some 200 m 2 ) by values of somewhat more than 25 mg/s. Because of the lack of other weather conditions the dispersion experiments were exclusively realized during weak to moderate winds. Small scale fire induced maximum inhalation hazards from PuO 2 -powder used in production essentially exceeded those of large scale conflagrations. Obviously the activity intake by inhalation exceeded to some extent the admissable threshold of the annual activity intake. (orig.) [de

  13. Reduction of the dynamic response by aircraft crash on building structures

    International Nuclear Information System (INIS)

    Krutzik, N.J.

    1988-01-01

    Through the use of the double-shell concept the dynamic loads applied by a hypothetical aircraft impact as well as the response of the structure can be reduced significantly. Steel-fiber-reinforced concrete shells with thicknesses of about 0.8 m have a sufficient nonlinear capacity for loads applied by a military airplane such as the Phantom jet. The secondary impact after damage of the outer shell as well as the dynamic response of the structure can be additionally reduced using damping material supporting the impacted shell. Construction of the double shell design does not result in any practical problems. (orig./HP)

  14. Probabilistic approach to requalification of existing NPPs under aircraft crash loading

    International Nuclear Information System (INIS)

    Birbraer, A.N.; Roleder, A.J.; Shulman, G.S.

    1993-01-01

    A probabilistic approach to the analysis of NPP safety under aircraft impact is discussed. It may be used both for requalification of existing NPPs and in the process of NPP design. NPP is considered as a system of components: structures, pipes, different kinds of equipment, soil, foundation. The exceeding of the limit probability of the radioactive products release out of containment (i.e. of the NPP safety requirements non-fulfilment) is taken as a system failure criterion. An example of an event tree representing the consequence of events causing the failure is given. Described are the methods of estimate of elementary events probabilities through which a composite probability of the failure is evaluated. (author)

  15. AP1000R design robustness against extreme external events - Seismic, flooding, and aircraft crash

    International Nuclear Information System (INIS)

    Pfister, A.; Goossen, C.; Coogler, K.; Gorgemans, J.

    2012-01-01

    Both the International Atomic Energy Agency (IAEA) and the U.S. Nuclear Regulatory Commission (NRC) require existing and new nuclear power plants to conduct plant assessments to demonstrate the unit's ability to withstand external hazards. The events that occurred at the Fukushima-Dai-ichi nuclear power station demonstrated the importance of designing a nuclear power plant with the ability to protect the plant against extreme external hazards. The innovative design of the AP1000 R nuclear power plant provides unparalleled protection against catastrophic external events which can lead to extensive infrastructure damage and place the plant in an extended abnormal situation. The AP1000 plant is an 1100-MWe pressurized water reactor with passive safety features and extensive plant simplifications that enhance construction, operation, maintenance and safety. The plant's compact safety related footprint and protection provided by its robust nuclear island structures prevent significant damage to systems, structures, and components required to safely shutdown the plant and maintain core and spent fuel pool cooling and containment integrity following extreme external events. The AP1000 nuclear power plant has been extensively analyzed and reviewed to demonstrate that it's nuclear island design and plant layout provide protection against both design basis and extreme beyond design basis external hazards such as extreme seismic events, external flooding that exceeds the maximum probable flood limit, and malicious aircraft impact. The AP1000 nuclear power plant uses fail safe passive features to mitigate design basis accidents. The passive safety systems are designed to function without safety-grade support systems (such as AC power, component cooling water, service water, compressed air or HVAC). The plant has been designed to protect systems, structures, and components critical to placing the reactor in a safe shutdown condition within the steel containment vessel which is

  16. AP1000{sup R} design robustness against extreme external events - Seismic, flooding, and aircraft crash

    Energy Technology Data Exchange (ETDEWEB)

    Pfister, A.; Goossen, C.; Coogler, K.; Gorgemans, J. [Westinghouse Electric Company LLC, 1000 Westinghouse Drive, Cranberry Township, PA 16066 (United States)

    2012-07-01

    Both the International Atomic Energy Agency (IAEA) and the U.S. Nuclear Regulatory Commission (NRC) require existing and new nuclear power plants to conduct plant assessments to demonstrate the unit's ability to withstand external hazards. The events that occurred at the Fukushima-Dai-ichi nuclear power station demonstrated the importance of designing a nuclear power plant with the ability to protect the plant against extreme external hazards. The innovative design of the AP1000{sup R} nuclear power plant provides unparalleled protection against catastrophic external events which can lead to extensive infrastructure damage and place the plant in an extended abnormal situation. The AP1000 plant is an 1100-MWe pressurized water reactor with passive safety features and extensive plant simplifications that enhance construction, operation, maintenance and safety. The plant's compact safety related footprint and protection provided by its robust nuclear island structures prevent significant damage to systems, structures, and components required to safely shutdown the plant and maintain core and spent fuel pool cooling and containment integrity following extreme external events. The AP1000 nuclear power plant has been extensively analyzed and reviewed to demonstrate that it's nuclear island design and plant layout provide protection against both design basis and extreme beyond design basis external hazards such as extreme seismic events, external flooding that exceeds the maximum probable flood limit, and malicious aircraft impact. The AP1000 nuclear power plant uses fail safe passive features to mitigate design basis accidents. The passive safety systems are designed to function without safety-grade support systems (such as AC power, component cooling water, service water, compressed air or HVAC). The plant has been designed to protect systems, structures, and components critical to placing the reactor in a safe shutdown condition within the steel

  17. On the response of a reactor building and its equipment to aircraft crash

    International Nuclear Information System (INIS)

    Larsson, G.; Lundsager, P.

    1977-01-01

    The present study investigates the dynamic response of the ASEA-ATOM BWR 75 reactor building in terms of response spectra at significant locations considering various aircraft and points of load application. In the first part of the study a total of 21 forcing functions, most of them from the open literature and including the commonly used standard functions, have been studied with respect to documentation, consistency and frequency content. Since none of the forcing functions have been experimentally verified, their validity must be assessed mainly by judging the structural models and assumptions used in their derivation and by checking their consistency. In the second part, linear dynamical models of various degrees of detailedness have been investigated regarding their capacity to describe the behavior of the reactor building under this high frequency loading. The most detailed model consists of plane stress finite elements for every significant wall and floor. In the third part of the study the effects of a number of parameters on the response of the building are investigated. The parameters include the points of attack, damping values, soil spring stiffness as well as different forcing functions of various frequency contents. The reponse is displayed as response spectra and member forces for characteristic locations. The results serve as a basis for development of standardized design floor response spectra and for the structural verification of the bui

  18. Assessment of the response of reinforced concrete structural members to aircraft crash impact loading

    International Nuclear Information System (INIS)

    Brandes, K.

    1988-01-01

    For the containments of nuclear power plants in the Federal Republic of Germany, the loading caused by a striking military aircraft decisively influences their design. The low probability of occurrence of this loading can be associated with an increase of consequences and reduced safety margins used in the design of structures. This requires that the actual response of structures to extreme loads has to be predicted with a higher degree of confidence than is typically the case with conventional structures. The adequacy of the computer-oriented mechanical-mathematical methods and the associated computer-codes used in the design of nuclear power plants can only be verified by comparing results from both, analytical and experimental studies. After having confirmed the adequacy of the analytical tools, a probabilistic risk analysis can be sufficiently performed. A series of tests is described which have been performed with the aim to improve the mechanical and physical modelling of RC-structures. Furthermore, a case study is presented to evolve a feeling for the safety margins which are implicitely included in the deterministic design calculation. (orig.)

  19. Analysis of the impact of an aircraft crash on underground concrete ducts with protective slab at reactor buildings

    International Nuclear Information System (INIS)

    Kotulla, B.; Hansson, V.

    1977-01-01

    In this paper different types of idealization for a dynamic analysis of underground concrete ducts with protective slab are discussed and compared. Ducts between reactor and control building of a nuclear power plant are to be designed for loadings produced by an aircraft crash. These ducts have a height of about three to four meters and are two to eight meters wide. They are designed with a protective slab about 1.5 m in thickness at ground level and with an intermediate layer of earth of about one meter in thickness. An analysis has to take into account the combined effects of a protective slab with a relatively thin intermediate layer of earth and the underlaying duct and layer of soil with the nonlinear behavior of concrete due to cracking. For describing this behavior two types of idealization were made. One type is a continuum type calculation which describes the slab, the soil and the duct by finite elements. In the other type of idealization a model consisting of springs and lumped masses is used. The protective slab and the intermediate layer of earth may be described as a plate on elastic foundation. The behavior of the cracked part of the plate and the part of earth layer beneath and loads transferred to the uncracked part of the slab and the surrounding soil may be described by parallel springs. Spring and mass of this part of the model have to take into account the cracking of the upper slab which leads to a nonlinear characteristic of the spring. In addition the location of the loading in relation to the duct has to be considered. The duct may be described by a beam on elastic foundation which is loaded locally. From this model representative mass and spring have to be determined

  20. 36 CFR 327.4 - Aircraft.

    Science.gov (United States)

    2010-07-01

    ..., helicopters, ultra-light aircraft, motorized hang gliders, hot air balloons, any non-powered flight devices or..., material or equipment by parachute, balloon, helicopter or other means onto or from project lands or waters...

  1. Influence of the aircraft crash induced local nonlinearities on the overall dynamic response of a RC structure through a parametric study

    International Nuclear Information System (INIS)

    Rouzaud, C.; Gatuingt, F.; Hervé, G.; Moussallam, N.; Dorival, O.

    2016-01-01

    Highlights: • Structures could resist to the induced accelerations which they might undergo. • The characterization of non-linearities in the signal of an aircraft impact. • The non linear impact area are studied through a sensitivity analysis. • This analysis should allow to achieve a link between aircraft impact parameters. - Abstract: In the process of nuclear power plant design, the safety of structures is an important aspect. Civil engineering structures have to resist the accelerations induced by, for example, seismic loads or shaking loads resulting from the aircraft impact. This is even more important for the in-structures equipments that have also to be qualified against the vibrations generated by this kind of hazards. In the case of aircraft crash, as a large variety of scenarios has to be envisaged, it is necessary to use methods that are less CPU-time consuming and that consider appropriately the nonlinearities. The analysis presented in this paper deals with the problem of the characterization of nonlinearities (damaged area, transmitted force) in the response of a structure subjected to an aircraft impact. The purpose of our study is part of the development of a new decoupled nonlinear and elastic way for calculating the shaking of structures following an aircraft impact which could be very numerically costly if studied with classical finite element methods. The aim is to identify which parameters control the dimensions of the nonlinear zone and so will have a direct impact on the induced vibrations. In a design context, several load cases (and simulations) are analyzed in order to consider a wide range of impact (different loading surfaces, momentum) and data sets of the target (thickness, reinforcements). In this work, the nonlinear area generated by the impact is localized and studied through a parametric analysis associated with a sensitivity analysis to identify the boundaries between the elastic domain and this nonlinear area.

  2. Development of a probabilistic safety assessment framework for an interim dry storage facility subjected to an aircraft crash using best-estimate structural analysis

    Energy Technology Data Exchange (ETDEWEB)

    Almomani, Belal; Jang, Dong Chan [Dept. of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Lee, Sang Hoon [Dept. of Mechanical and Automotive Engineering, Keimyung University, Daegu (Korea, Republic of); Kang, Hyun Gook [Dept. of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy (United States)

    2017-03-15

    Using a probabilistic safety assessment, a risk evaluation framework for an aircraft crash into an interim spent fuel storage facility is presented. Damage evaluation of a detailed generic cask model in a simplified building structure under an aircraft impact is discussed through a numerical structural analysis and an analytical fragility assessment. Sequences of the impact scenario are shown in a developed event tree, with uncertainties considered in the impact analysis and failure probabilities calculated. To evaluate the influence of parameters relevant to design safety, risks are estimated for three specification levels of cask and storage facility structures. The proposed assessment procedure includes the determination of the loading parameters, reference impact scenario, structural response analyses of facility walls, cask containment, and fuel assemblies, and a radiological consequence analysis with dose–risk estimation. The risk results for the proposed scenario in this study are expected to be small relative to those of design basis accidents for best-estimated conservative values. The importance of this framework is seen in its flexibility to evaluate the capability of the facility to withstand an aircraft impact and in its ability to anticipate potential realistic risks; the framework also provides insight into epistemic uncertainty in the available data and into the sensitivity of the design parameters for future research.

  3. Development of a Probabilistic Safety Assessment Framework for an Interim Dry Storage Facility Subjected to an Aircraft Crash Using Best-Estimate Structural Analysis

    Directory of Open Access Journals (Sweden)

    Belal Almomani

    2017-03-01

    Full Text Available Using a probabilistic safety assessment, a risk evaluation framework for an aircraft crash into an interim spent fuel storage facility is presented. Damage evaluation of a detailed generic cask model in a simplified building structure under an aircraft impact is discussed through a numerical structural analysis and an analytical fragility assessment. Sequences of the impact scenario are shown in a developed event tree, with uncertainties considered in the impact analysis and failure probabilities calculated. To evaluate the influence of parameters relevant to design safety, risks are estimated for three specification levels of cask and storage facility structures. The proposed assessment procedure includes the determination of the loading parameters, reference impact scenario, structural response analyses of facility walls, cask containment, and fuel assemblies, and a radiological consequence analysis with dose–risk estimation. The risk results for the proposed scenario in this study are expected to be small relative to those of design basis accidents for best-estimated conservative values. The importance of this framework is seen in its flexibility to evaluate the capability of the facility to withstand an aircraft impact and in its ability to anticipate potential realistic risks; the framework also provides insight into epistemic uncertainty in the available data and into the sensitivity of the design parameters for future research.

  4. Development of a probabilistic safety assessment framework for an interim dry storage facility subjected to an aircraft crash using best-estimate structural analysis

    International Nuclear Information System (INIS)

    Almomani, Belal; Jang, Dong Chan; Lee, Sang Hoon; Kang, Hyun Gook

    2017-01-01

    Using a probabilistic safety assessment, a risk evaluation framework for an aircraft crash into an interim spent fuel storage facility is presented. Damage evaluation of a detailed generic cask model in a simplified building structure under an aircraft impact is discussed through a numerical structural analysis and an analytical fragility assessment. Sequences of the impact scenario are shown in a developed event tree, with uncertainties considered in the impact analysis and failure probabilities calculated. To evaluate the influence of parameters relevant to design safety, risks are estimated for three specification levels of cask and storage facility structures. The proposed assessment procedure includes the determination of the loading parameters, reference impact scenario, structural response analyses of facility walls, cask containment, and fuel assemblies, and a radiological consequence analysis with dose–risk estimation. The risk results for the proposed scenario in this study are expected to be small relative to those of design basis accidents for best-estimated conservative values. The importance of this framework is seen in its flexibility to evaluate the capability of the facility to withstand an aircraft impact and in its ability to anticipate potential realistic risks; the framework also provides insight into epistemic uncertainty in the available data and into the sensitivity of the design parameters for future research

  5. Ultralight porous metals: From fundamentals to applications

    Science.gov (United States)

    Lu, Tianjian

    2002-10-01

    Over the past few years a number of low cost metallic foams have been produced and used as the core of sandwich panels and net shaped parts. The main aim is to develop lightweight structures which are stiff, strong, able to absorb large amount of energy and cheap for application in the transport and construction industries. For example, the firewall between the engine and passenger compartment of an automobile must have adequate mechanical strength, good energy and sound absorbing properties, and adequate fire retardance. Metal foams provide all of these features, and are under serious consideration for this applications by a number of automobile manufacturers (e.g., BMW and Audi). Additional specialized applications for foam-cored sandwich panels range from heat sinks for electronic devices to crash barriers for automobiles, from the construction panels in lifts on aircraft carriers to the luggage containers of aircraft, from sound proofing walls along railway tracks and highways to acoustic absorbers in lean premixed combustion chambers. But there is a problem. Before metallic foams can find a widespread application, their basic properties must be measured, and ideally modeled as a function of microstructural details, in order to be included in a design. This work aims at reviewing the recent progress and presenting some new results on fundamental research regarding the micromechanical origins of the mechanical, thermal, and acoustic properties of metallic foams.

  6. Ultralight porous metals. From fundamentals to applications

    International Nuclear Information System (INIS)

    Lu, T.

    2002-01-01

    Over the past few years a number of low cost metallic foams for application as the core of sandwich panels and net shaped parts have been produced. The main aim is to develop lightweight structures which are stiff, strong, absorb large amount of energy and are cheap, for application in the transport and construction industries. For example, the firewall between the engine and passenger compartment of an automobile must have adequate mechanical strength, good energy and sound absorbing properties, and adequate fire retardance. Metal foams provide all of these features, and are under serious scrutiny for this applications by a number of automobile manufacturers (e.g., BMW and Audi). Additional specialized applications for foam-cored sandwich panels range from heat sinks for electronic devices to crash barriers for automobiles, from the construction panels in lifts on aircraft carriers to the luggage containers of aircraft, from sound proofing walls along railway tracks and highways to acoustic absorbers in lean premixed combustion chambers. But there is a problem. Before metallic foams can find widespread application, their basic properties must be measured, and ideally modeled as a function of microstructural details, in order to give a design capability. This work aims at reviewing recent progress and present some new results on fundamental research regarding the micromechanical origins of the mechanical, thermal, and acoustic properties of metallic foams. (author)

  7. Nonlinear analysis of commercial aircraft impact on a reactor building—Comparison between integral and decoupled crash simulation

    Energy Technology Data Exchange (ETDEWEB)

    Siefert, A., E-mail: siefert@woelfel.de; Henkel, F.O.

    2014-04-01

    Since 9/11, the crash of a commercial aeroplane on the reactor building of a nuclear power plant is a realistic design scenario. Before that the structural behaviour under a crash of a military plane was investigated by a procedure using load-time functions (Riera, 1968). Thereby, the computation of the load-time-function was based on a conceptional model considering the main stiffness parts and masses by discrete elements. With respect to the homogeneous structural set-up of a military plane, the application of this model and the derived load-time-function applied as lumped load case seems very feasible. Contrary thereto the structural set-up of a commercial aeroplane, with e.g. the high mass concentration of the turbine or the high stiffness of the wing box compared to other parts, is different. This can be counteracted by using a more detailed finite element (FE) model for the computation of the load-time-function and by dividing the load case for the reactor building in different main load zones. Although this represents a more detailed investigation, the procedure of using a load-time-function still has the disadvantage to separate the real scenario into two steps. Thereby, the direct interaction between the structure and the aeroplane including all softening effects due to material respectively structural compliances is neglected. This leads to the general conclusion that by applying load-time-functions the results are conservative compared to the real behaviour. Due to the increased capabilities of numerical software solutions it is also possible nowadays to carry out integral crash simulations, combining all effects within one simulation. Compared to the procedure of using load-time-functions, the numerical complexity and therefore the amount of work for this integral method are increased. Within this paper both procedures (load-time function by detailed FE-model and the integral method) are exemplarily compared to each other by a crash analysis of an

  8. Nonlinear analysis of commercial aircraft impact on a reactor building—Comparison between integral and decoupled crash simulation

    International Nuclear Information System (INIS)

    Siefert, A.; Henkel, F.O.

    2014-01-01

    Since 9/11, the crash of a commercial aeroplane on the reactor building of a nuclear power plant is a realistic design scenario. Before that the structural behaviour under a crash of a military plane was investigated by a procedure using load-time functions (Riera, 1968). Thereby, the computation of the load-time-function was based on a conceptional model considering the main stiffness parts and masses by discrete elements. With respect to the homogeneous structural set-up of a military plane, the application of this model and the derived load-time-function applied as lumped load case seems very feasible. Contrary thereto the structural set-up of a commercial aeroplane, with e.g. the high mass concentration of the turbine or the high stiffness of the wing box compared to other parts, is different. This can be counteracted by using a more detailed finite element (FE) model for the computation of the load-time-function and by dividing the load case for the reactor building in different main load zones. Although this represents a more detailed investigation, the procedure of using a load-time-function still has the disadvantage to separate the real scenario into two steps. Thereby, the direct interaction between the structure and the aeroplane including all softening effects due to material respectively structural compliances is neglected. This leads to the general conclusion that by applying load-time-functions the results are conservative compared to the real behaviour. Due to the increased capabilities of numerical software solutions it is also possible nowadays to carry out integral crash simulations, combining all effects within one simulation. Compared to the procedure of using load-time-functions, the numerical complexity and therefore the amount of work for this integral method are increased. Within this paper both procedures (load-time function by detailed FE-model and the integral method) are exemplarily compared to each other by a crash analysis of an

  9. A Study of Transport Airplane Crash-Resistant Fuel Systems

    National Research Council Canada - National Science Library

    Robertson, S

    2002-01-01

    ...), of transport airplane crash-resistant fuel system (CRFS). The report covers the historical studies related to aircraft crash fires and fuel containment concepts undertaken by the FAA, NASA, and the U.S...

  10. Evaluation of aluminum ultralight rigid wheelchairs versus other ultralight wheelchairs using ANSI/RESNA standards.

    Science.gov (United States)

    Liu, Hsin-yi; Pearlman, Jonathan; Cooper, Rosemarie; Hong, Eun-kyoung; Wang, Hongwu; Salatin, Benjamin; Cooper, Rory A

    2010-01-01

    Previous studies found that select titanium ultralight rigid wheelchairs (TURWs) had fewer equivalent cycles and less value than select aluminum ultralight folding wheelchairs (AUFWs). The causes of premature failure of TURWs were not clear because the TURWs had different frame material and design than the AUFWs. We tested 12 aluminum ultralight rigid wheelchairs (AURWs) with similar frame designs and dimensions as the TURWs using the American National Standards Institute/Rehabilitation Engineering and Assistive Technology Society of North America and International Organization for Standardization wheelchair standards and hypothesized that the AURWs would be more durable than the TURWs. Across wheelchair models, no significant differences were found in the test results between the AURWs and TURWs, except in their overall length. Tire pressure, tube-wall thickness, and tube manufacturing were proposed to be the factors affecting wheelchair durability through comparison of the failure modes, frames, and components. The frame material did not directly affect the performance of AURWs and TURWs, but proper wheelchair manufacture and design based on mechanical properties are important.

  11. Design of Carbon Composite Driveshaft for Ultralight Aircraft Propulsion System

    Directory of Open Access Journals (Sweden)

    R. Poul

    2006-01-01

    Full Text Available This paper deals with the design of the carbon fibre composite driveshaft. This driveshaft will be used for connection between piston engine and propulsor of the type of axial-flow fan. Three different versions of driveshaft were designed and produced. Version 1 if completely made of Al alloy. Version 2 is of hybrid design where the central part is made of high strength carbon composite and flanges are made of Al alloy. Adhesive bond is used for connection between flanges and the central CFRP tube. Version 3 differs from the version 2 by aplication of ultrahigh-strength carbon fibre on the central part. Dimensions and design conditions are equal for all three versions to obtain simply comparable results. Calculations of driveshafts are described in the paper. 

  12. Pedestrian Crashes

    Data.gov (United States)

    Town of Chapel Hill, North Carolina — This data set maps the locations of crashes involving pedestrians in the Chapel Hill Region of North Carolina.The data comes from police-reported bicycle-motor...

  13. Bicycle Crashes

    Data.gov (United States)

    Town of Chapel Hill, North Carolina — This data set maps the locations of crashes involving bicyclists in the Chapel Hill Region of North Carolina.The data comes from police-reported bicycle-motor...

  14. Alien plant monitoring with ultralight airborne imaging spectroscopy.

    Directory of Open Access Journals (Sweden)

    María Calviño-Cancela

    Full Text Available Effective management of invasive plants requires a precise determination of their distribution. Remote sensing techniques constitute a promising alternative to field surveys and hyperspectral sensors (also known as imaging spectrometers, with a large number of spectral bands and high spectral resolution are especially suitable when very similar categories are to be distinguished (e.g. plant species. A main priority in the development of this technology is to lower its cost and simplify its use, so that its demonstrated aptitude for many environmental applications can be truly realized. With this aim, we have developed a system for hyperspectral imaging (200 spectral bands in the 380-1000 nm range and circa 3 nm spectral resolution operated on board ultralight aircraft (namely a gyrocopter, which allows a drastic reduction of the running costs and operational complexity of image acquisition, and also increases the spatial resolution of the images (circa 5-8 pixels/m(2 at circa 65 km/h and 300 m height. The detection system proved useful for the species tested (Acacia melanoxylon, Oxalis pes-caprae, and Carpobrotus aff. edulis and acinaciformis, with user's and producer's accuracy always exceeding 90%. The detection accuracy reported corresponds to patches down to 0.125 m(2 (50% of pixels 0.5 × 0.5 m in size, a very small size for many plant species, making it very effective for initial stages of invasive plant spread. In addition, its low operating costs, similar to those of a 4WD ground vehicle, facilitate frequent image acquisition. Acquired images constitute a permanent record of the status of the study area, with great amount of information that can be analyzed in the future for other purposes, thus greatly facilitating the monitoring of natural areas at detailed spatial and temporal scales for improved management.

  15. Airplane crash

    International Nuclear Information System (INIS)

    Brunner, P.

    1975-01-01

    In May, 1974, a severe airplane crash occurred near Springfield, llinois; the crew of three and a courier were killed. The plane was carrying a large container of controlled water with a slight amount of 60 Co. A survey of the crash site by Air Force detectives and the radiological assistance team from Wright--Patterson Air Force Base indicated no radioactivity. Experiences of the incident were used to develop guidelines for future emergency preparedness

  16. Database on aircraft accidents

    International Nuclear Information System (INIS)

    Nishio, Masahide; Koriyama, Tamio

    2013-11-01

    The Reactor Safety Subcommittee in the Nuclear Safety and Preservation Committee published 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' as the standard method for evaluating probability of aircraft crash into nuclear reactor facilities in July 2002. In response to this issue, Japan Nuclear Energy Safety Organization has been collecting open information on aircraft accidents of commercial airplanes, self-defense force (SDF) airplanes and US force airplanes every year since 2003, sorting out them and developing the database of aircraft accidents for the latest 20 years to evaluate probability of aircraft crash into nuclear reactor facilities. In this report the database was revised by adding aircraft accidents in 2011 to the existing database and deleting aircraft accidents in 1991 from it, resulting in development of the revised 2012 database for the latest 20 years from 1992 to 2011. Furthermore, the flight information on commercial aircrafts was also collected to develop the flight database for the latest 20 years from 1992 to 2011 to evaluate probability of aircraft crash into reactor facilities. The method for developing the database of aircraft accidents to evaluate probability of aircraft crash into reactor facilities is based on the report 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' described above. The 2012 revised database for the latest 20 years from 1992 to 2011 shows the followings. The trend of the 2012 database changes little as compared to the last year's report. (1) The data of commercial aircraft accidents is based on 'Aircraft accident investigation reports of Japan transport safety board' of Ministry of Land, Infrastructure, Transport and Tourism. The number of commercial aircraft accidents is 4 for large fixed-wing aircraft, 58 for small fixed-wing aircraft, 5 for large bladed aircraft and 99 for small bladed aircraft. The relevant accidents

  17. Cross-country VFR crashes: pilot and contextual factors.

    Science.gov (United States)

    O'Hare, David; Owen, Douglas

    2002-04-01

    General Aviation (GA) cross-country crashes, particularly those involving weather, continue to be a major source of fatalities, with a fatality rate more than four times greater than for GA crashes in general. There has been much speculation and little solid evidence on the causes of these crashes. We have designed a program of laboratory and database research into the causes of cross-country weather-related crashes including an analysis of air crashes in New Zealand between 1988 and 2000. There were 1308 reported occurrences in this period. We examined in detail 77 crashes where it could be determined that the aircraft was on a cross-country flight. In our first analysis we compared the characteristics of crashes that occurred in response to externally driven failures with crashes where the aircraft continued to be flown at the pilot's discretion up until the point of the crash. Clear differences were found for visibility, altitude, crash severity, and for several pilot characteristics. These differences are highly consistent with those found for previous research on pilot characteristics and crash involvement. In the second analysis we made comparisons between the weather-related and nonweather-related crashes in the discretionary control group and between subcategories of weather-related crashes. These data show that weather-related crashes occur further into the flight and closer to the planned destination than other kinds of cross-country crashes in GA. Pilots involved in these crashes are younger and have more recent flight time than pilots involved in other crashes. Their increased involvement cannot be explained simply by exposure (flight-time) but must be due to other factors.

  18. Database on aircraft accidents

    International Nuclear Information System (INIS)

    Nishio, Masahide; Koriyama, Tamio

    2012-09-01

    The Reactor Safety Subcommittee in the Nuclear Safety and Preservation Committee published the report 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' as the standard method for evaluating probability of aircraft crash into nuclear reactor facilities in July 2002. In response to the report, Japan Nuclear Energy Safety Organization has been collecting open information on aircraft accidents of commercial airplanes, self-defense force (SDF) airplanes and US force airplanes every year since 2003, sorting out them and developing the database of aircraft accidents for latest 20 years to evaluate probability of aircraft crash into nuclear reactor facilities. This year, the database was revised by adding aircraft accidents in 2010 to the existing database and deleting aircraft accidents in 1991 from it, resulting in development of the revised 2011 database for latest 20 years from 1991 to 2010. Furthermore, the flight information on commercial aircrafts was also collected to develop the flight database for latest 20 years from 1991 to 2010 to evaluate probability of aircraft crash into reactor facilities. The method for developing the database of aircraft accidents to evaluate probability of aircraft crash into reactor facilities is based on the report 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' described above. The 2011 revised database for latest 20 years from 1991 to 2010 shows the followings. The trend of the 2011 database changes little as compared to the last year's one. (1) The data of commercial aircraft accidents is based on 'Aircraft accident investigation reports of Japan transport safety board' of Ministry of Land, Infrastructure, Transport and Tourism. 4 large fixed-wing aircraft accidents, 58 small fixed-wing aircraft accidents, 5 large bladed aircraft accidents and 114 small bladed aircraft accidents occurred. The relevant accidents for evaluating

  19. Perturbations of ultralight vector field dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Cembranos, J.A.R.; Maroto, A.L.; Jareño, S.J. Núñez [Departamento de Física Teórica I, Universidad Complutense de Madrid, E-28040 Madrid (Spain)

    2017-02-13

    We study the dynamics of cosmological perturbations in models of dark matter based on ultralight coherent vector fields. Very much as for scalar field dark matter, we find two different regimes in the evolution: for modes with k{sup 2}≪Hma, we have a particle-like behaviour indistinguishable from cold dark matter, whereas for modes with k{sup 2}≫Hma, we get a wave-like behaviour in which the sound speed is non-vanishing and of order c{sub s}{sup 2}≃k{sup 2}/m{sup 2}a{sup 2}. This implies that, also in these models, structure formation could be suppressed on small scales. However, unlike the scalar case, the fact that the background evolution contains a non-vanishing homogeneous vector field implies that, in general, the evolution of the three kinds of perturbations (scalar, vector and tensor) can no longer be decoupled at the linear level. More specifically, in the particle regime, the three types of perturbations are actually decoupled, whereas in the wave regime, the three vector field perturbations generate one scalar-tensor and two vector-tensor perturbations in the metric. Also in the wave regime, we find that a non-vanishing anisotropic stress is present in the perturbed energy-momentum tensor giving rise to a gravitational slip of order (Φ−Ψ)/Φ∼c{sub s}{sup 2}. Moreover in this regime the amplitude of the tensor to scalar ratio of the scalar-tensor modes is also h/Φ∼c{sub s}{sup 2}. This implies that small-scale density perturbations are necessarily associated to the presence of gravity waves in this model. We compare their spectrum with the sensitivity of present and future gravity waves detectors.

  20. Descriptive and analytical epidemiology of accidents in five categories of sport aviation aircraft

    NARCIS (Netherlands)

    van Doorn, R.R.A.; de Voogt, A.J.

    2011-01-01

    The present study reports and compares causes of, and factors contributing to, 2,118 documented accidents of sport aviation represented by diverse aircraft types including balloons and blimps, gliders, gyroplanes, and ultralights. For the 26-year period, accidents were aircraft-specific regarding

  1. 14 CFR 29.952 - Fuel system crash resistance.

    Science.gov (United States)

    2010-01-01

    ... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Fuel System § 29.952 Fuel system... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel system crash resistance. 29.952... of fuel fires to occupants following an otherwise survivable impact (crash landing), the fuel systems...

  2. 14 CFR 27.952 - Fuel system crash resistance.

    Science.gov (United States)

    2010-01-01

    ... AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Fuel System § 27.952 Fuel system... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel system crash resistance. 27.952... of fuel fires to occupants following an otherwise survivable impact (crash landing), the fuel systems...

  3. Ultralight Nanolattices with Co-Optimized Mechanical, Thermal, and Optical Properties

    Data.gov (United States)

    National Aeronautics and Space Administration — This research aims to develop ultralight nanostructured materials with optimized properties in multiple physical domains. The proposed approach is based on...

  4. THE COMPARATIVE ECONOMIC-MATHEMATICAL ANALYSIS OF EFFICIENCY OF APPLICATION ON THE ACW OF THE ULTRALIGHT X-32 "BEKAS" PLANE AND THE MOTOR HANG-GLIDER MD-50S

    Directory of Open Access Journals (Sweden)

    2016-01-01

    Full Text Available In this article the comparative economic-mathematical analysis of size of profit per a flight hour on use at the avia- tion-chemical works (ACW of two types of super light aircraft X-32 “Bekas” and a glider MD-50S which are widely used when cultivating farmland nowadays. The list of indicators which are used while carrying out the comparative technical and economic analysis of considered ultralights is given at the beginning of the article. Further their numerical values nec- essary for computations are given. The mathematical formula for calculation with use of the given data of profit on carrying out ACW with use of the considered models of the aircraft equipment is presented. Values of profit are calculated by means of the tabular Microsoft Excel editor for various values of cultivated farmland length and distance of approach from airfield to the cultivated plot. The applied values of cultivated farmland length lie in the range from 0.5 to 10 kilometers, and ap-proach distances vary from 0.5 to 2 kilometers respectively. Calculations are executed for each of two compared ultralights and results are given in a tabular form respectively. On the basis of the analysis of the obtained tabular data conclusions are drawn under what values of input and variables in the form of farmland length and distance of approach profit margin for each of two ultralights will be larger or smaller in comparison with each other. In the final part of article total conclusions about the most preferable ultralight of two compared for operation in fields of various configuration during ACW are drawn. At the end recommendations to the aviation enterprises about application of the most expedient option of ultralight for obtaining bigger profit margin on carrying out ACW.

  5. Civil aircraft side-facing seat research summary.

    Science.gov (United States)

    2012-11-01

    The Federal Aviation Administration (FAA) has standards and regulations that are intended to protect aircraft : occupants in the event of a crash. However, side-facing seats were not specifically addressed when aircraft seat : dynamic test standards ...

  6. Motor Carrier Crash Data -

    Data.gov (United States)

    Department of Transportation — Contains data on large trucks and buses involved in Federally reportable crashes as per Title 49 U.S.C. Part 390.5 (crashes involving a commercial motor vehicle, and...

  7. Cumulative effects in inflation with ultra-light entropy modes

    Energy Technology Data Exchange (ETDEWEB)

    Achúcarro, Ana; Atal, Vicente [Instituut-Lorentz for Theoretical Physics, Universiteit Leiden, 2333 CA Leiden (Netherlands); Germani, Cristiano [Institut de Ciéncies del Cosmos, Universitat de Barcelona, Martí i Franqués 1, 08028 Barcelona (Spain); Palma, Gonzalo A., E-mail: achucar@lorentz.leidenuniv.nl, E-mail: vicente.atal@icc.ub.edu, E-mail: germani@icc.ub.edu, E-mail: gpalmaquilod@ing.uchile.cl [Grupo de Cosmología y Astrofísica Teórica, Departamento de Física, FCFM, Universidad de Chile, Blanco Encalada 2008, Santiago (Chile)

    2017-02-01

    In multi-field inflation one or more non-adiabatic modes may become light, potentially inducing large levels of isocurvature perturbations in the cosmic microwave background. If in addition these light modes are coupled to the adiabatic mode, they influence its evolution on super horizon scales. Here we consider the case in which a non-adiabatic mode becomes approximately massless (''ultralight') while still coupled to the adiabatic mode, a typical situation that arises with pseudo-Nambu-Goldstone bosons or moduli. This ultralight mode freezes on super-horizon scales and acts as a constant source for the curvature perturbation, making it grow linearly in time and effectively suppressing the isocurvature component. We identify a Stückelberg-like emergent shift symmetry that underlies this behavior. As inflation lasts for many e -folds, the integrated effect of this source enhances the power spectrum of the adiabatic mode, while keeping the non-adiabatic spectrum approximately untouched. In this case, towards the end of inflation all the fluctuations, adiabatic and non-adiabatic, are dominated by a single degree of freedom.

  8. Hazards from aircraft

    International Nuclear Information System (INIS)

    Grund, J.E.; Hornyik, K.

    1975-01-01

    The siting of nuclear power plants has created innumerable environmental concerns. Among the effects of the ''man-made environment'' one of increasing importance in recent nuclear plant siting hazards analysis has been the concern about aircraft hazards to the nuclear plant. These hazards are of concern because of the possibility that an aircraft may have a malfunction and crash either near the plant or directly into it. Such a crash could be postulated to result, because of missile and/or fire effects, in radioactive releases which would endanger the public health and safety. The majority of studies related to hazards from air traffic have been concerned with the determination of the probability associated with an aircraft striking vulnerable portions of a given plant. Other studies have focused on the structural response to such a strike. This work focuses on the problem of strike probability. 13 references

  9. Pulsar timing signal from ultralight scalar dark matter

    International Nuclear Information System (INIS)

    Khmelnitsky, Andrei; Rubakov, Valery

    2014-01-01

    An ultralight free scalar field with mass around 10 −23 −10 −22 eV is a viable dark mater candidate, which can help to resolve some of the issues of the cold dark matter on sub-galactic scales. We consider the gravitational field of the galactic halo composed out of such dark matter. The scalar field has oscillating in time pressure, which induces oscillations of gravitational potential with amplitude of the order of 10 −15 and frequency in the nanohertz range. This frequency is in the range of pulsar timing array observations. We estimate the magnitude of the pulse arrival time residuals induced by the oscillating gravitational potential. We find that for a range of dark matter masses, the scalar field dark matter signal is comparable to the stochastic gravitational wave signal and can be detected by the planned SKA pulsar timing array experiment

  10. AP statistics crash course

    CERN Document Server

    D'Alessio, Michael

    2012-01-01

    AP Statistics Crash Course - Gets You a Higher Advanced Placement Score in Less Time Crash Course is perfect for the time-crunched student, the last-minute studier, or anyone who wants a refresher on the subject. AP Statistics Crash Course gives you: Targeted, Focused Review - Study Only What You Need to Know Crash Course is based on an in-depth analysis of the AP Statistics course description outline and actual Advanced Placement test questions. It covers only the information tested on the exam, so you can make the most of your valuable study time. Our easy-to-read format covers: exploring da

  11. Distracted Driving Raises Crash Risk

    Science.gov (United States)

    ... this issue Health Capsule Distracted Driving Raises Crash Risk En español Send us your comments Video technology ... distracted driving, especially among new drivers, raises the risk for car crashes and near crashes. The study ...

  12. Review of Aircraft Crash Structural Response Research.

    Science.gov (United States)

    1982-08-01

    11Ilk LAS VEGAS A-CIDE NT CABIN FLOOR CONTROLLED TESI CABIN FLOOP Fig 6 Damage comparison between controlled test and Las %egas acc¢ident. P IL •I...damage pattern to the standard passenger and crew seats of the shortly after taking off from the North Las Vegas Airport. Chieftain was similar to...8217Hoekstra, H C. and iuan, S. C., "aety ’Alfaro-Bou, Emilio , Fasanella, , in General Aviation," Fliqnt Safety -oundatlon, and Wiliiams, 4, Susan

  13. Annoyance by aircraft noise and fear of overflying aircraft in relation to attitudes toward the environment and community

    Science.gov (United States)

    Loeb, M.; Moran, S. V.

    1977-01-01

    It has been suggested that expressions of annoyance attributable to aircraft noise may reflect in part fear of aircraft overflights and possible crashes. If this is true, then residents of areas where crashes have occurred should express more annoyance. To test this hypothesis, 50 residents of an Albany, New York area where an aircraft crash producing fatalities recently occurred and 50 residents of a comparable nearby area without such a history, were asked to respond to a 'Quality of Life Questionnaire.' Among the items were some designed to test annoyance by noise and fear of aircraft overflights. It was predicted that those in the crash area would express more fear and would more often identify aircraft as a noise source. These hypotheses were sustained. A near-replication was carried out in Louisville, Kentucky; results were much the same. Analyses indicated that for the crash-area groups, there was associating of aircraft fear and noise annoyance responses; this was true to an apparently lesser extent for non-crash groups. The greater annoyance of crash groups by aircraft community noise apparently does not carry over to situations in which aircraft noise is assessed in the laboratory.

  14. Road crash costs.

    NARCIS (Netherlands)

    2010-01-01

    Road crashes result in all kinds of social costs, such as medical costs, production loss, human losses, property damage, settlement costs and costs due to congestion. Studies into road crash costs and their trends are carried out quite regularly. In 2009, the costs amounted to € 12.5 billion, or

  15. Development of ultralight, super-elastic, hierarchical metallic meta-structures with i3DP technology

    Science.gov (United States)

    Zhang, Dongxing; Xiao, Junfeng; Moorlag, Carolyn; Guo, Qiuquan; Yang, Jun

    2017-11-01

    Lightweight and mechanically robust materials show promising applications in thermal insulation, energy absorption, and battery catalyst supports. This study demonstrates an effective method for creation of ultralight metallic structures based on initiator-integrated 3D printing technology (i3DP), which provides a possible platform to design the materials with the best geometric parameters and desired mechanical performance. In this study, ultralight Ni foams with 3D interconnected hollow tubes were fabricated, consisting of hierarchical features spanning three scale orders ranging from submicron to centimeter. The resultant materials can achieve an ultralight density of as low as 5.1 mg cm-3 and nearly recover after significant compression up to 50%. Due to a high compression ratio, the hierarchical structure exhibits superior properties in terms of energy absorption and mechanical efficiency. The relationship of structural parameters and mechanical response was established. The ability of achieving ultralight density printing approach provides metallic structures with substantial benefits from the hierarchical design and fabrication flexibility to ultralight applications.

  16. Stochastic and Resolvable Gravitational Waves from Ultralight Bosons.

    Science.gov (United States)

    Brito, Richard; Ghosh, Shrobana; Barausse, Enrico; Berti, Emanuele; Cardoso, Vitor; Dvorkin, Irina; Klein, Antoine; Pani, Paolo

    2017-09-29

    Ultralight scalar fields around spinning black holes can trigger superradiant instabilities, forming a long-lived bosonic condensate outside the horizon. We use numerical solutions of the perturbed field equations and astrophysical models of massive and stellar-mass black hole populations to compute, for the first time, the stochastic gravitational-wave background from these sources. In optimistic scenarios the background is observable by Advanced LIGO and LISA for field masses m_{s} in the range ∼[2×10^{-13},10^{-12}] and ∼5×[10^{-19},10^{-16}]  eV, respectively, and it can affect the detectability of resolvable sources. Our estimates suggest that an analysis of the stochastic background limits from LIGO O1 might already be used to marginally exclude axions with mass ∼10^{-12.5}  eV. Semicoherent searches with Advanced LIGO (LISA) should detect ∼15(5) to 200(40) resolvable sources for scalar field masses 3×10^{-13} (10^{-17})  eV. LISA measurements of massive BH spins could either rule out bosons in the range ∼[10^{-18},2×10^{-13}]  eV, or measure m_{s} with 10% accuracy in the range ∼[10^{-17},10^{-13}]  eV.

  17. Allegheny County Crash Data

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Contains locations and information about every crash incident reported to the police in Allegheny County from 2004 to 2016. Fields include injury severity,...

  18. Allegheny County Crash Data

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Contains locations and information about every crash incident reported to the police in Allegheny County from 2004 to 2017. Fields include injury severity,...

  19. Pilot ejection, parachute, and helicopter crash injuries.

    Science.gov (United States)

    McBratney, Colleen M; Rush, Stephen; Kharod, Chetan U

    2014-01-01

    USAF Pararescuemen (PJs) respond to downed aircrew as a fundamental mission for personnel recovery (PR), one of the Air Force's core functions. In addition to responding to these in Military settings, the PJs from the 212 Rescue Squadron routinely respond to small plane crashes in remote regions of Alaska. While there is a paucity of information on the latter, there have been articles detailing injuries sustained from helicopter crashes and while ejecting or parachuting from fixed wing aircraft. The following represents a new chapter added to the Pararescue Medical Operations Handbook, Sixth Edition (2014, editors Matt Wolf, MD, and Stephen Rush, MD, in press). It was designed to be a quick reference for PJs and their Special Operations flight surgeons to help with understanding of mechanism of injury with regard to pilot ejection, parachute, and helicopter accident injuries. It outlines the nature of the injuries sustained in such mishaps and provides an epidemiologic framework from which to approach the problem. 2014.

  20. Estimating likelihood of future crashes for crash-prone drivers

    OpenAIRE

    Subasish Das; Xiaoduan Sun; Fan Wang; Charles Leboeuf

    2015-01-01

    At-fault crash-prone drivers are usually considered as the high risk group for possible future incidents or crashes. In Louisiana, 34% of crashes are repeatedly committed by the at-fault crash-prone drivers who represent only 5% of the total licensed drivers in the state. This research has conducted an exploratory data analysis based on the driver faultiness and proneness. The objective of this study is to develop a crash prediction model to estimate the likelihood of future crashes for the a...

  1. Critical market crashes

    Science.gov (United States)

    Sornette, D.

    2003-04-01

    This review presents a general theory of financial crashes and of stock market instabilities that his co-workers and the author have developed over the past seven years. We start by discussing the limitation of standard analyses for characterizing how crashes are special. The study of the frequency distribution of drawdowns, or runs of successive losses shows that large financial crashes are “outliers”: they form a class of their own as can be seen from their statistical signatures. If large financial crashes are “outliers”, they are special and thus require a special explanation, a specific model, a theory of their own. In addition, their special properties may perhaps be used for their prediction. The main mechanisms leading to positive feedbacks, i.e., self-reinforcement, such as imitative behavior and herding between investors are reviewed with many references provided to the relevant literature outside the narrow confine of Physics. Positive feedbacks provide the fuel for the development of speculative bubbles, preparing the instability for a major crash. We demonstrate several detailed mathematical models of speculative bubbles and crashes. A first model posits that the crash hazard drives the market price. The crash hazard may sky-rocket at some times due to the collective behavior of “noise traders”, those who act on little information, even if they think they “know”. A second version inverses the logic and posits that prices drive the crash hazard. Prices may skyrocket at some times again due to the speculative or imitative behavior of investors. According the rational expectation model, this entails automatically a corresponding increase of the probability for a crash. We also review two other models including the competition between imitation and contrarian behavior and between value investors and technical analysts. The most important message is the discovery of robust and universal signatures of the approach to crashes. These precursory

  2. Crash sequence based risk matrix for motorcycle crashes.

    Science.gov (United States)

    Wu, Kun-Feng; Sasidharan, Lekshmi; Thor, Craig P; Chen, Sheng-Yin

    2018-04-05

    Considerable research has been conducted related to motorcycle and other powered-two-wheeler (PTW) crashes; however, it always has been controversial among practitioners concerning with types of crashes should be first targeted and how to prioritize resources for the implementation of mitigating actions. Therefore, there is a need to identify types of motorcycle crashes that constitute the greatest safety risk to riders - most frequent and most severe crashes. This pilot study seeks exhibit the efficacy of a new approach for prioritizing PTW crash causation sequences as they relate to injury severity to better inform the application of mitigating countermeasures. To accomplish this, the present study constructed a crash sequence-based risk matrix to identify most frequent and most severe motorcycle crashes in an attempt to better connect causes and countermeasures of PTW crashes. Although the frequency of each crash sequence can be computed from crash data, a crash severity model is needed to compare the levels of crash severity among different crash sequences, while controlling for other factors that also have effects on crash severity such drivers' age, use of helmet, etc. The construction of risk matrix based on crash sequences involve two tasks: formulation of crash sequence and the estimation of a mixed-effects (ME) model to adjust the levels of severities for each crash sequence to account for other crash contributing factors that would have an effect on the maximum level of crash severity in a crash. Three data elements from the National Automotive Sampling System - General Estimating System (NASS-GES) data were utilized to form a crash sequence: critical event, crash types, and sequence of events. A mixed-effects model was constructed to model the severity levels for each crash sequence while accounting for the effects of those crash contributing factors on crash severity. A total of 8039 crashes involving 8208 motorcycles occurred during 2011 and 2013 were

  3. Estimating likelihood of future crashes for crash-prone drivers

    Directory of Open Access Journals (Sweden)

    Subasish Das

    2015-06-01

    Full Text Available At-fault crash-prone drivers are usually considered as the high risk group for possible future incidents or crashes. In Louisiana, 34% of crashes are repeatedly committed by the at-fault crash-prone drivers who represent only 5% of the total licensed drivers in the state. This research has conducted an exploratory data analysis based on the driver faultiness and proneness. The objective of this study is to develop a crash prediction model to estimate the likelihood of future crashes for the at-fault drivers. The logistic regression method is used by employing eight years' traffic crash data (2004–2011 in Louisiana. Crash predictors such as the driver's crash involvement, crash and road characteristics, human factors, collision type, and environmental factors are considered in the model. The at-fault and not-at-fault status of the crashes are used as the response variable. The developed model has identified a few important variables, and is used to correctly classify at-fault crashes up to 62.40% with a specificity of 77.25%. This model can identify as many as 62.40% of the crash incidence of at-fault drivers in the upcoming year. Traffic agencies can use the model for monitoring the performance of an at-fault crash-prone drivers and making roadway improvements meant to reduce crash proneness. From the findings, it is recommended that crash-prone drivers should be targeted for special safety programs regularly through education and regulations.

  4. 14 CFR 61.52 - Use of aeronautical experience obtained in ultralight vehicles.

    Science.gov (United States)

    2010-01-01

    ... ratings issued under this part: (1) A sport pilot certificate. (2) A flight instructor certificate with a sport pilot rating; (3) A private pilot certificate with a weight-shift-control or powered parachute... provisions of §§ 61.69 and 61.415(e). (c) A person using aeronautical experience obtained in an ultralight...

  5. Use of ultralight aircraft for material location and road surveys in remote rural areas

    CSIR Research Space (South Africa)

    Jones, DJ

    2006-10-01

    Full Text Available . Botanical indicators in road construction include trees, shrubs, flowers and grasses, although ferns and fungi may also be relevant. The presence of many plant species and even the nature of their growth often depend on the mineralogical and physical... of leaves, abnormally shaped fruits, changes of colour in the flowers, disturbances in the rhythm of the flowering period and changes in growth form. Total plant biomass towards less dense or more open conditions is common in areas of ultramafic rock...

  6. Aircraft Crash Survival Design Guide. Volume 2. Aircraft Crash Environment and Human Tolerance

    Science.gov (United States)

    1980-01-01

    a whipping action’of the head, and often, impact of the upper torso on the legs, resulting in chest, head, and neck injuries . Head injuries due to...K., at al., COMPARATIVE TOLERANCE FOR CEREBRAL CONCUSSION BY HEAD IMPACT AND WHIPLASH INJURY IN PRIMATES , 1970 International Automobile Safety...FROM HEAD IMPACT AND WHIPLASH IN PRIMATES , Journal of Biomechanics, Vol. 4, 1971, pp. 13-21. 18. Goldsmith, W., BIOMECHANICS OF HEAD INJURY , In

  7. Time-varying Crash Risk

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Feunoua, Bruno; Jeon, Yoontae

    We estimate a continuous-time model with stochastic volatility and dynamic crash probability for the S&P 500 index and find that market illiquidity dominates other factors in explaining the stock market crash risk. While the crash probability is time-varying, its dynamic depends only weakly on re...

  8. Health and usage monitoring system for the small aircraft composite structure

    Science.gov (United States)

    Růžička, Milan; Dvořák, Milan; Schmidová, Nikola; Šašek, Ladislav; Štěpánek, Martin

    2017-07-01

    This paper is focused on the design of the health and usage monitoring system (HUMS) of the composite ultra-light aircrafts. A multichannel measuring system was developed and installed for recording of the long-term operational measurements of the UL airplane. Many fiber Bragg grating sensors were implemented into the composite aircraft structure, mainly in the glue joints. More than ten other analog functions and signals of the aircraft is monitored and can be correlated together. Changing of the FBG sensors responses in monitored places and their correlations, comparing with the calibration and recalibration procedures during a monitored life may indicate damage (eg. in bonded joints) and complements the HUMS system.

  9. Phantom crash confirms models

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    To test computer models of how a nuclear reactor's containment building would fare if an airplane crashed into it, the Muto Institute in Tokyo sponsored a 3.2 million dollar project at Sandia National Laboratory to slam an F-4 Phantom jet into a 500 ton concrete wall. The results showed that the computer calculations were accurate

  10. Advances in Crash Response

    Centers for Disease Control (CDC) Podcasts

    In this podcast, Dr. Richard C. Hunt, Director of CDC's Division of Injury Response, provides an overview on the benefits of using an Advanced Automatic Collision Notification system, or AACN, to help with emergency triage of people injured in vehicle crashes.

  11. General aviation crash safety program at Langley Research Center

    Science.gov (United States)

    Thomson, R. G.

    1976-01-01

    The purpose of the crash safety program is to support development of the technology to define and demonstrate new structural concepts for improved crash safety and occupant survivability in general aviation aircraft. The program involves three basic areas of research: full-scale crash simulation testing, nonlinear structural analyses necessary to predict failure modes and collapse mechanisms of the vehicle, and evaluation of energy absorption concepts for specific component design. Both analytical and experimental methods are being used to develop expertise in these areas. Analyses include both simplified procedures for estimating energy absorption capabilities and more complex computer programs for analysis of general airframe response. Full-scale tests of typical structures as well as tests on structural components are being used to verify the analyses and to demonstrate improved design concepts.

  12. Structural design for aircraft impact loading

    International Nuclear Information System (INIS)

    Schmidt, R.; Heckhausen, H.; Chen, C.; Rieck, P.J.; Lemons, G.W.

    1977-01-01

    The Soft Shell-Hardcore approach to nuclear power plant auxiliary structure design was developed to attenuate the crash effects of impacting aircraft. This report is an initial investigation into defining the important structural features involved that would allow the Soft Shell-Hardcore design to successfully sustain the postulated aircraft impact. Also specified for purposes of this study are aircraft impact locations and the type and velocity of impacting aircraft. The purpose of this initial investigation is to determine the feasibility of the two 0.5 m thick walls of the Soft Shell with the simplest possible mathematical model

  13. Ultralight mesoporous magnetic frameworks by interfacial assembly of Prussian blue nanocubes.

    Science.gov (United States)

    Kong, Biao; Tang, Jing; Wu, Zhangxiong; Wei, Jing; Wu, Hao; Wang, Yongcheng; Zheng, Gengfeng; Zhao, Dongyuan

    2014-03-10

    A facile approach for the synthesis of ultralight iron oxide hierarchical structures with tailorable macro- and mesoporosity is reported. This method entails the growth of porous Prussian blue (PB) single crystals on the surface of a polyurethane sponge, followed by in situ thermal conversion of PB crystals into three-dimensional mesoporous iron oxide (3DMI) architectures. Compared to previously reported ultralight materials, the 3DMI architectures possess hierarchical macro- and mesoporous frameworks with multiple advantageous features, including high surface area (ca. 117 m(2) g(-1)) and ultralow density (6-11 mg cm(-3)). Furthermore, they can be synthesized on a kilogram scale. More importantly, these 3DMI structures exhibit superparamagnetism and tunable hydrophilicity/hydrophobicity, thus allowing for efficient multiphase interfacial adsorption and fast multiphase catalysis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Perbandingan Stock Market Crash 1987 : Dan Stock Market Crash 1997

    OpenAIRE

    Indridewi Atmadjaja, Yovita Vivianty

    1999-01-01

    Stock market crash refers to the condition, which is marked with the large dropping of stock Market price index. Historically, stock market crash has happened three times, namely in 1929, 1987 and 1997. This paper will discuss the causes of 1987's and 1997's stock market Crash and the similarities and the differences between 1987's and 1997's stock market crash. The structure of the paper is as follows. The paper starts with the introduction. The second Section briefly explains the causes of ...

  15. Advances in Crash Response

    Centers for Disease Control (CDC) Podcasts

    2009-06-29

    In this podcast, Dr. Richard C. Hunt, Director of CDC's Division of Injury Response, provides an overview on the benefits of using an Advanced Automatic Collision Notification system, or AACN, to help with emergency triage of people injured in vehicle crashes.  Created: 6/29/2009 by National Center for Injury Prevention and Control (NCIPC), Division of Injury Response (DIR).   Date Released: 6/29/2009.

  16. Structural integrity analysis of an Ignalina nuclear power plant building subjected to an airplane crash

    International Nuclear Information System (INIS)

    Dundulis, Gintautas; Kulak, Ronald F.; Marchertas, Algirdas; Uspuras, Eugenijus

    2007-01-01

    Recent terrorist attacks using commandeered commercial airliners on civil structures have raised the issue of the ability of nuclear power plants to survive the consequences of an airliner crash. The structural integrity analysis due to the effects of an aircraft crash on an Ignalina nuclear power plant (INPP) accident localization system (ALS) building is the subject of this paper. A combination of the finite element method and empirical relationships were used for the analysis. A global structural integrity analysis was performed for a portion of the ALS building using the dynamic loading from an aircraft crash impact model. The local effects caused by impact of the aircraft's engine on the building wall were evaluated independently by using an empirical formula. The results from the crash analysis of a twin engine commercial aircraft show that the impacted reinforced concrete wall of the ALS building will not have through-the-wall concrete failure, and the reinforcement will not fail. Strain-rate effects were found to delay the onset of cracking. Therefore, the structural integrity of the impacted wall of the INPP ALS building will be maintained during the crash event studied

  17. Structural integrity analysis of an Ignalina nuclear power plant building subjected to an airplane crash

    Energy Technology Data Exchange (ETDEWEB)

    Dundulis, Gintautas [Laboratory of Nuclear Installation Safety, Lithuanian Energy Institute, 3 Breslaujos, 44403 Kaunas-35 (Lithuania)]. E-mail: gintas@isag.lei.lt; Kulak, Ronald F. [RFK Engineering Mechanics Consultants (United States); Marchertas, Algirdas [Northern Illinois University (United States); Uspuras, Eugenijus [Laboratory of Nuclear Installation Safety, Lithuanian Energy Institute, 3 Breslaujos, 44403 Kaunas-35 (Lithuania)

    2007-08-15

    Recent terrorist attacks using commandeered commercial airliners on civil structures have raised the issue of the ability of nuclear power plants to survive the consequences of an airliner crash. The structural integrity analysis due to the effects of an aircraft crash on an Ignalina nuclear power plant (INPP) accident localization system (ALS) building is the subject of this paper. A combination of the finite element method and empirical relationships were used for the analysis. A global structural integrity analysis was performed for a portion of the ALS building using the dynamic loading from an aircraft crash impact model. The local effects caused by impact of the aircraft's engine on the building wall were evaluated independently by using an empirical formula. The results from the crash analysis of a twin engine commercial aircraft show that the impacted reinforced concrete wall of the ALS building will not have through-the-wall concrete failure, and the reinforcement will not fail. Strain-rate effects were found to delay the onset of cracking. Therefore, the structural integrity of the impacted wall of the INPP ALS building will be maintained during the crash event studied.

  18. Identification of Aircraft Hazards

    Energy Technology Data Exchange (ETDEWEB)

    K. Ashley

    2006-12-08

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2005 [DIRS 174235], Section 6.4.1). That determination was conservatively based upon limited knowledge of flight data in the area of concern and upon crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a monitored geologic repository (MGR) at Yucca Mountain, using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987 [DIRS 103124], Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. The intended use of this report is to provide inputs for further screening and analysis of identified aircraft hazards based upon the criteria that apply to Category 1 and Category 2 event sequence analyses as defined in 10 CFR 63.2 [DIRS 176544] (Section 4). The scope of this report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the repository at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (Section 7).

  19. IDENTIFICATION OF AIRCRAFT HAZARDS

    International Nuclear Information System (INIS)

    K.L. Ashley

    2005-01-01

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in the ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2004, Section 6.4.1). That determination was conservatively based on limited knowledge of flight data in the area of concern and on crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a Monitored Geologic Repository (MGR) at Yucca Mountain using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987, Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. NUREG-0800 is being used here as a reference because some of the same considerations apply. The intended use of this report is to provide inputs for further screening and analysis of the identified aircraft hazards based on the criteria that apply to Category 1 and 2 event sequence analyses as defined in 10 CFR 63.2 (see Section 4). The scope of this technical report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the MGR at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (see Section 7)

  20. Identification of Aircraft Hazards

    International Nuclear Information System (INIS)

    K. Ashley

    2006-01-01

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2005 [DIRS 174235], Section 6.4.1). That determination was conservatively based upon limited knowledge of flight data in the area of concern and upon crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a monitored geologic repository (MGR) at Yucca Mountain, using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987 [DIRS 103124], Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. The intended use of this report is to provide inputs for further screening and analysis of identified aircraft hazards based upon the criteria that apply to Category 1 and Category 2 event sequence analyses as defined in 10 CFR 63.2 [DIRS 176544] (Section 4). The scope of this report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the repository at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (Section 7)

  1. Superior microwave absorption properties of ultralight reduced graphene oxide/black phosphorus aerogel

    Science.gov (United States)

    Hao, Chunxue; Wang, Bochong; Wen, Fusheng; Mu, Congpu; Xiang, Jianyong; Li, Lei; Liu, Zhongyuan

    2018-06-01

    Through a facile self-assembled process, an ultralight reduced graphene oxide/black phosphorus (rGO/BP) composite aerogel was successfully fabricated. The BP nanosheets were homogeneously distributed throughout the rGO 3D framework, and the interfaces between rGO and BP possessed four kinds of interconnections, such as wrapping, wearing, bridging and weak linking. As an ultralight composite, the rGO/BP aerogel could easily stand on the stamen of a flower. Compared with pure rGO aerogel, the rGO/BP composite aerogel exhibited enhanced microwave absorption ability. The minimum reflection loss value of ‑46.9 dB with a thickness of 2.53 mm was obtained, and a wide absorption band of 6.1 GHz (RL < ‑10 dB) was achieved. The superior microwave absorption property was demonstrated to stem from the interfacial polarization loss mechanism in which the multiform interface interactions between the rGO skeleton and BP nanosheets played critical roles. The rGO/BP aerogel has great potential to be used as an ultralight microwave absorber.

  2. General Models for Assessing Hazards Aircraft Pose to Surface Facilities

    International Nuclear Information System (INIS)

    Ragan, G.E.

    2002-01-01

    This paper derives formulas for estimating the frequency of accidental aircraft crashes into surface facilities. Objects unintentionally dropped from aircraft are also considered. The approach allows the facility to be well within the flight area; inside the flight area, but close to the edge; or completely outside the flight area

  3. Large truck and bus crash facts, 2010.

    Science.gov (United States)

    2012-09-01

    This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2010. Selected crash statistics on passenger : vehicles are also presen...

  4. Large truck and bus crash facts, 2012.

    Science.gov (United States)

    2014-06-01

    This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and property damage only crashes involving large trucks and buses in 2012. Selected crash statistics on passenger vehicles are also presented ...

  5. Large truck and bus crash facts, 2013.

    Science.gov (United States)

    2015-04-01

    This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and property damage only crashes involving large trucks and buses in 2013. Selected crash statistics on passenger vehicles are also presented ...

  6. Large truck and bus crash facts, 2009.

    Science.gov (United States)

    2011-10-01

    This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2009. Selected crash statistics on passenger : vehicles are also presen...

  7. Large truck and bus crash facts, 2011.

    Science.gov (United States)

    2013-10-01

    This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2011. Selected crash statistics on passenger : vehicles are also presen...

  8. Omitted variable bias in crash reduction factors.

    Science.gov (United States)

    2015-09-01

    Transportation planners and traffic engineers are increasingly turning to crash reduction factors to evaluate changes in road : geometric and design features in order to reduce crashes. Crash reduction factors are typically estimated based on segment...

  9. Helicopter crashes into water: warning time, final position, and other factors affecting survival.

    Science.gov (United States)

    Brooks, Christopher J; MacDonald, Conor V; Baker, Susan P; Shanahan, Dennis F; Haaland, Wren L

    2014-04-01

    According to 40 yr of data, the fatality rate for a helicopter crash into water is approximately 25%. Does warning time and the final position of the helicopter in the water influence the survival rate? The National Transportation Safety Board (NTSB) database was queried to identify helicopter crashes into water between 1981 and 2011 in the Gulf of Mexico and Hawaii. Fatality rate, amount of warning time prior to the crash, and final position of the helicopter were identified. There were 133 helicopters that crashed into water with 456 crew and passengers. Of these, 119 occupants (26%) did not survive; of those who did survive, 38% were injured. Twelve died after making a successful escape from the helicopter. Crashes with 1 min. However, more than half of fatalities (57%) came from crashes for which the warning time could not be determined. Lack of warning time and how to survive in the water after the crash should be a topic for study in all marine survival/aircraft ditching courses. Investigators should be trained to provide estimates of warning time when investigating helicopter crashes into water.

  10. 41 CFR 302-7.20 - If my HHG shipment includes an item (e.g., boat, trailer, ultralight vehicle) for which a weight...

    Science.gov (United States)

    2010-07-01

    ... includes an item (e.g., boat, trailer, ultralight vehicle) for which a weight additive is assessed by the...) General Rules § 302-7.20 If my HHG shipment includes an item (e.g., boat, trailer, ultralight vehicle) for which a weight additive is assessed by the HHG carrier, am I responsible for payment? If your HHG...

  11. Connected motorcycle crash warning interfaces.

    Science.gov (United States)

    2016-01-15

    Crash warning systems have been deployed in the high-end vehicle market segment for some time and are trickling down to additional motor vehicle industry segments each year. The motorcycle segment, however, has no deployed crash warning system to dat...

  12. Resisting "Crash Diet" Staff Development

    Science.gov (United States)

    Dana, Nancy Fichtman; Yendol-Hoppey, Diane

    2008-01-01

    People often respond to the pressure of attending a high school reunion or their child's wedding by going on a crash diet to get quick results. In response, friends may marvel about how good they look on the outside. But what folks don't acknowledge is that, in the name of getting results, crash dieters have done some very unhealthy things to…

  13. Mitigating Wind Induced Truck Crashes

    Science.gov (United States)

    2009-12-25

    Dangerous weather and high wind in particular, is a common contributing factor in truck crashes. High wind speeds have been documented as a perennial cause of truck crashes in Kansas and other Great Plains states. The possibility of reducing such cra...

  14. Braking news: link between crash severity and crash avoidance maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    across severity levels were estimated to accommodate the ordered-response nature of severity. The sample used for estimation consisted of data for single-vehicle crashes extracted from the General Estimates System crash database for the period from 2005 to 2009. Results showed the correlation between...... of lower crash severity. These trends suggest that efforts to understand the mechanisms of reactions to different critical events should be made to improve in-vehicle warning systems, promote responsible driving behavior, and design forgiving infrastructures....

  15. Some failure analyses of South African Air Force aircraft engine and airframe components

    CSIR Research Space (South Africa)

    Benson, JM

    1998-06-01

    Full Text Available Failure analyses of various engine and airframe components from South African Air Force aircraft have been performed by the Division of Materials Science and Technology over several years and these have ranged from crash investigations to minor...

  16. Ultralight, Flexible, and Semi-Transparent Metal Oxide Papers for Photoelectrochemical Water Splitting

    DEFF Research Database (Denmark)

    Zhang, Minwei; Hou, Chengyi; Halder, Arnab

    2017-01-01

    nanostructure and macroscopic morphology of MOs that aims to enhance their performances, but the design and controlled synthesis of ultrafine nanostructured MOs in a cost-effective and facile way remains a challenge. In this work, we have exploited the advantages of intrinsic structures of graphene oxide (GO......) papers, serving as a sacrificial template, to design and synthesize two-dimensional (2D) layered and free-standing MO papers with ultrafine nanostructures. Physicochemical characterizations showed that these MO materials are nanostructured, porous, flexible, and ultralight. The as-synthesized materials...

  17. Development of ultra-light pixelated ladders for an ILC vertex detector

    CERN Document Server

    Chon-Sen, N.; Claus, G.; De Masi, R.; Deveaux, M.; Dulinski, W.; Goffe, M.; Goldstein, J.; Gregor, I.-M.; Hu-Guo, Ch.; Imhoff, M.; Muntz, C.; Nomerotski, A.; Santos, C.; Schrader, C.; Specht, M.; Stroth, J.; Winter, M.

    2010-01-01

    The development of ultra-light pixelated ladders is motivated by the requirements of the ILD vertex detector at ILC. This paper summarizes three projects related to system integration. The PLUME project tackles the issue of assembling double-sided ladders. The SERWIETE project deals with a more innovative concept and consists in making single-sided unsupported ladders embedded in an extra thin plastic enveloppe. AIDA, the last project, aims at building a framework reproducing the experimental running conditions where sets of ladders could be tested.

  18. Statistical analysis of vehicle crashes in Mississippi based on crash data from 2010 to 2014.

    Science.gov (United States)

    2017-08-15

    Traffic crash data from 2010 to 2014 were collected by Mississippi Department of Transportation (MDOT) and extracted for the study. Three tasks were conducted in this study: (1) geographic distribution of crashes; (2) descriptive statistics of crash ...

  19. Intelligent geocoding system to locate traffic crashes.

    Science.gov (United States)

    Qin, Xiao; Parker, Steven; Liu, Yi; Graettinger, Andrew J; Forde, Susie

    2013-01-01

    State agencies continue to face many challenges associated with new federal crash safety and highway performance monitoring requirements that use data from multiple and disparate systems across different platforms and locations. On a national level, the federal government has a long-term vision for State Departments of Transportation (DOTs) to report state route and off-state route crash data in a single network. In general, crashes occurring on state-owned or state maintained highways are a priority at the Federal and State level; therefore, state-route crashes are being geocoded by state DOTs. On the other hand, crashes occurring on off-state highway system do not always get geocoded due to limited resources and techniques. Creating and maintaining a statewide crash geographic information systems (GIS) map with state route and non-state route crashes is a complicated and expensive task. This study introduces an automatic crash mapping process, Crash-Mapping Automation Tool (C-MAT), where an algorithm translates location information from a police report crash record to a geospatial map and creates a pinpoint map for all crashes. The algorithm has approximate 83 percent mapping rate. An important application of this work is the ability to associate the mapped crash records to underlying business data, such as roadway inventory and traffic volumes. The integrated crash map is the foundation for effective and efficient crash analyzes to prevent highway crashes. Published by Elsevier Ltd.

  20. Alcohol and older drivers' crashes.

    Science.gov (United States)

    2014-09-01

    Researchers have examined the effects of alcohol consumption : on older adults functioning, and some have : addressed alcohols effects on older drivers crash risk. : Generally, the findings have shown that alcohol is less : likely to be a fa...

  1. Improving freight crash incident management.

    Science.gov (United States)

    2015-06-01

    The objective of this study was to determine the most effective way to mitigate the effect of freight : crash incidents on Louisiana freeways. Candidate incident management strategies were reviewed from : practice in other states and from those publi...

  2. Crash course in readers' advisory

    CERN Document Server

    Orr, Cynthia

    2014-01-01

    One of the key services librarians provide is helping readers find books they'll enjoy. This ""crash course"" will furnish you with the basic, practical information you need to excel at readers' advisory (RA) for adults and teens.

  3. Crash Lethality Model

    Science.gov (United States)

    2012-06-06

    of Death from Burn Injuries, New England Journal of Medicine. Massachusetts, Feb 1998. 11. Crull, Michelle. Tatom, John. Conway, Robert . SPIDER 2... Raymer , Daniel P. Aircraft Design: A Conceptual Approach. Washington DC: American Institute of Aeronautics and Astronautics, Inc., 1992. ISBN 0-930403...Patuxent River, MD 20670 NAVAIRSYSCOM (AIR-5.1G - Roberts ), Bldg. 8010 (1) 47320 Priests Point Loop, St. Inigoes, MD 20684-4017 NAVAIRSYSCOM (UASTD

  4. Motorcycle crashes potentially preventable by three crash avoidance technologies on passenger vehicles.

    Science.gov (United States)

    Teoh, Eric R

    2018-07-04

    The objective of this study was to identify and quantify the motorcycle crash population that would be potential beneficiaries of 3 crash avoidance technologies recently available on passenger vehicles. Two-vehicle crashes between a motorcycle and a passenger vehicle that occurred in the United States during 2011-2015 were classified by type, with consideration of the functionality of 3 classes of passenger vehicle crash avoidance technologies: frontal crash prevention, lane maintenance, and blind spot detection. Results were expressed as the percentage of crashes potentially preventable by each type of technology, based on all known types of 2-vehicle crashes and based on all crashes involving motorcycles. Frontal crash prevention had the largest potential to prevent 2-vehicle motorcycle crashes with passenger vehicles. The 3 technologies in sum had the potential to prevent 10% of fatal 2-vehicle crashes and 23% of police-reported crashes. However, because 2-vehicle crashes with a passenger vehicle represent fewer than half of all motorcycle crashes, these technologies represent a potential to avoid 4% of all fatal motorcycle crashes and 10% of all police-reported motorcycle crashes. Refining the ability of passenger vehicle crash avoidance systems to detect motorcycles represents an opportunity to improve motorcycle safety. Expanding the capabilities of these technologies represents an even greater opportunity. However, even fully realizing these opportunities can affect only a minority of motorcycle crashes and does not change the need for other motorcycle safety countermeasures such as helmets, universal helmet laws, and antilock braking systems.

  5. Preparation of ultra-light magnetic nanocomposites using highly concentrated emulsions

    International Nuclear Information System (INIS)

    Ghosh, Goutam; Vilchez, Alejandro; Esquena, Jordi; Solans, Conxita; Rodriguez-Abreu, Carlos

    2011-01-01

    Highlights: → Polystyrene-divinylbenzene-iron oxide nanocomposites. → Porous magnetic nanocomposites from highly concentrated emulsions. → Ultralight materials with relatively high magnetic moment. - Abstract: Hybrid inorganic-organic ultra-light magnetic solid foams with iron oxide nanoparticles embedded in a divinylbenzene-polystyrene matrix were prepared using a highly concentrated emulsion polymerization method. Iron oxide nanoparticles with diameters of 3 and 10 nm were synthesized using two different methods. For comparison purposes, nanocomposites with magnetite nanoparticles dispersed in a non-porous polymeric matrix obtained by bulk polymerization were also investigated. Materials were characterized using several techniques such as dynamic light scattering (DLS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), small angle X-ray scattering (SAXS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and magnetization measurements. SEM and TEM images showed that solid foams are made of well-defined macro pores with nanoparticles embedded in the walls. The density of the solid foams was ca. 50-70 kg m -3 , which is about 20 times lighter than the non-porous monoliths. The magnetic measurements show that both nanocomposites are superparamagnetic, and that there are differences regarding the interparticle interactions depending on matrix porosity. The synthesized materials may find applications in adsorbents, tissue reparation, enzyme supports, microreactors, or in water decontamination.

  6. Preparation of ultra-light magnetic nanocomposites using highly concentrated emulsions

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Goutam; Vilchez, Alejandro; Esquena, Jordi; Solans, Conxita [Instituto de Quimica Avanzada de Cataluna, Consejo Superior de Investigaciones Cientificas (IQAC-CSIC), Jordi Girona 18-26, 08034 Barcelona (Spain); Rodriguez-Abreu, Carlos, E-mail: carlos.rodriguez@inl.int [Instituto de Quimica Avanzada de Cataluna, Consejo Superior de Investigaciones Cientificas (IQAC-CSIC), Jordi Girona 18-26, 08034 Barcelona (Spain); International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jose Veiga, 4715-330 Braga (Portugal)

    2011-10-17

    Highlights: {yields} Polystyrene-divinylbenzene-iron oxide nanocomposites. {yields} Porous magnetic nanocomposites from highly concentrated emulsions. {yields} Ultralight materials with relatively high magnetic moment. - Abstract: Hybrid inorganic-organic ultra-light magnetic solid foams with iron oxide nanoparticles embedded in a divinylbenzene-polystyrene matrix were prepared using a highly concentrated emulsion polymerization method. Iron oxide nanoparticles with diameters of 3 and 10 nm were synthesized using two different methods. For comparison purposes, nanocomposites with magnetite nanoparticles dispersed in a non-porous polymeric matrix obtained by bulk polymerization were also investigated. Materials were characterized using several techniques such as dynamic light scattering (DLS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), small angle X-ray scattering (SAXS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and magnetization measurements. SEM and TEM images showed that solid foams are made of well-defined macro pores with nanoparticles embedded in the walls. The density of the solid foams was ca. 50-70 kg m{sup -3}, which is about 20 times lighter than the non-porous monoliths. The magnetic measurements show that both nanocomposites are superparamagnetic, and that there are differences regarding the interparticle interactions depending on matrix porosity. The synthesized materials may find applications in adsorbents, tissue reparation, enzyme supports, microreactors, or in water decontamination.

  7. Experimental Study of Ultralight (<300 kg/m3 Foamed Concrete

    Directory of Open Access Journals (Sweden)

    Xianjun Tan

    2014-01-01

    Full Text Available A type of ultralight (<300 kg/m3 foamed concrete (FC, which can be used as a new energy-conservation and environmental-protection building material and is particularly suitable for the thermal-insulation engineering of building external walls, was produced. The influences of different mixing amounts of fly ash, fly ash activator, WC (WC ratio, and foaming agent (FA on the compressive strength of FC were reported. The experimental study indicated that (1 the addition of fly ash reduced the strength of the FC and that the appropriate mixing amount of fly ash in this ultralight FC system should not exceed 45%; (2 with the increasing of fly ash activator, the strength of the FC sample is notably enhanced and the appropriate mixing amount of fly ash activator is 2.5%; (3 the optimized proportion of WC ratio is 0.45, and the FC that was produced according to this proportion has relatively high compressive strength; (4 by increasing the mixing amount of FA, the compressive strength of the FC notably decreases, and the optimal mixing amount of FA in this experiment is 3.5%.

  8. "Crashing the gates" - selection criteria for television news reporting of traffic crashes.

    Science.gov (United States)

    De Ceunynck, Tim; De Smedt, Julie; Daniels, Stijn; Wouters, Ruud; Baets, Michèle

    2015-07-01

    This study investigates which crash characteristics influence the probability that the crash is reported in the television news. To this purpose, all news items from the period 2006-2012 about traffic crashes from the prime time news of two Belgian television channels are linked to the official injury crash database. Logistic regression models are built for the database of all injury crashes and for the subset of fatal crashes to identify crash characteristics that correlate with a lower or higher probability of being reported in the news. A number of significant biases in terms of crash severity, time, place, types of involved road users and victims' personal characteristics are found in the media reporting of crashes. More severe crashes are reported in the media more easily than less severe crashes. Significant fluctuations in media reporting probability through time are found in terms of the year and month in which the crash took place. Crashes during week days are generally less reported in the news. The geographical area (province) in which the crash takes place also has a significant impact on the probability of being reported in the news. Crashes on motorways are significantly more represented in the news. Regarding the age of the involved victims, a clear trend of higher media reporting rates of crashes involving young victims or young fatalities is observed. Crashes involving female fatalities are also more frequently reported in the news. Furthermore, crashes involving a bus have a significantly higher probability of being reported in the news, while crashes involving a motorcycle have a significantly lower probability. Some models also indicate a lower reporting rate of crashes involving a moped, and a higher reporting rate of crashes involving heavy goods vehicles. These biases in media reporting can create skewed perceptions in the general public about the prevalence of traffic crashes and eventually may influence people's behaviour. Copyright © 2015

  9. Impact of ultralight axion self-interactions on the large scale structure of the Universe

    Science.gov (United States)

    Desjacques, Vincent; Kehagias, Alex; Riotto, Antonio

    2018-01-01

    Ultralight axions have sparked attention because their tiny mass m ˜10-22 eV , which leads to a kiloparsec-scale de Broglie wavelength comparable to the size of a dwarf galaxy, could alleviate the so-called small-scale crisis of massive cold dark matter (CDM) candidates. However, recent analyses of the Lyman-α forest power spectrum set a tight lower bound on their mass of m ≳10-21 eV which makes them much less relevant from an astrophysical point of view. An important caveat to these numerical studies is that they do not take into account self-interactions among ultralight axions. Furthermore, for axions which acquired a mass through nonperturbative effects, this self-interaction is attractive and, therefore, could counteract the quantum "pressure" induced by the strong delocalization of the particles. In this work, we show that even a tiny attractive interaction among ultralight axions can have a significant impact on the stability of cosmic structures at low redshift. After a brief review of known results about solitons in the absence of gravity, we discuss the stability of filamentary and pancakelike solutions when quantum pressure, attractive interactions and gravity are present. The analysis based on 1 degree of freedom, namely the breathing mode, reveals that pancakes are stable, while filaments are unstable if the mass per unit length is larger than a critical value. However, we show that pancakes are unstable against transverse perturbations. We expect this to be true for halos and filaments as well. Instabilities driven by the breathing mode will not be seen in the low column density Lyman-α forest unless the axion decay constant is extremely small, f ≲1013 GeV . Notwithstanding, axion solitonic cores could leave a detectable signature in the Lyman-α forest if the normalization of the unknown axion core—filament mass relation is ˜100 larger than it is for spherical halos. We hope our work motivates future numerical studies of the impact of axion

  10. Statewide analysis of bicycle crashes : [project summary].

    Science.gov (United States)

    2017-06-01

    An extensive literature review was conducted to locate existing studies in four areas: (1) risk factors that affect the frequency and severity of bicycle crashes; (2) bicycle crash causes, patterns, and contributing factors; (3) network screening met...

  11. Alcohol-crash problem in Canada, 2007

    Science.gov (United States)

    2010-03-01

    This report examines: data on alcohol in fatally injured drivers and pedestrians; the number and : percent of people who died in alcohol-related crashes; and alcohol involvement in those crashes : in which someone was seriously injured but not killed...

  12. Alcohol-crash problem in Canada, 2006

    Science.gov (United States)

    2009-01-01

    This report examines: data on alcohol in fatally injured drivers and pedestrians; the number and : percent of people who died in alcohol-related crashes; and alcohol involvement in those crashes : in which someone was seriously injured but not killed...

  13. Alcohol-crash problem in Canada, 2008

    Science.gov (United States)

    2010-12-01

    This report examines: data on alcohol in fatally injured drivers and pedestrians; the number and : percent of people who died in alcohol-related crashes; and alcohol involvement in those crashes : in which someone was seriously injured but not killed...

  14. National Motor Vehicle Crash Causation Survey (NMVCCS)

    Data.gov (United States)

    Department of Transportation — The National Motor Vehicle Crash Causation Survey (NMVVCS) was a nationwide survey of crashes involving light passenger vehicles, with a focus on the factors related...

  15. Teen driver crashes : a report to Congress

    Science.gov (United States)

    2008-07-01

    This report summarizes what is known about the teen driver crash problem and reviews the research on the major contributing factors to the high teen crash rate. Dispositional factors, such as immaturity, inexperience, faulty judgment, and a higher pr...

  16. 2004 road traffic crashes in Queensland

    Science.gov (United States)

    2009-05-01

    This report presents an overview of reported road traffic crashes in Queensland during : 2004 in the context of the previous five years based on data contained in the Queensland : Road Crash Information System maintained by the Department of Transpor...

  17. Effects from airplane crashes and gas explosions to Leningrad nuclear plant

    International Nuclear Information System (INIS)

    Junttila, K.; Varpasuo, P.

    1998-01-01

    In this study the effects of aircraft crash and gas explosion to Leningrad Nuclear Power Plant has been researched. One of the two reactor buildings is modeled with finite element method using the pre-processor program MSC/PATRAN and analyzed with MSC/NASTRAN analysis program. In MSC/PATRAN or FEMAP, which is a pre-processor program of MSC/NASTRAN for Windows, the reactor building of the plant has been modeled with shell and beam elements and the load sets describing the aircraft crash and gas explosion have been developed. The crash loads are from Cessna 210 civil airplane crash with impact velocity 360 km/h and maximum impact force of 7 MN and Phantom RF-43 military airplane crash with impact velocity 215 m/s and with maximum impact force of 110 MN. The gas explosion pressure wave simulates the deflagration wave with maximum pressure of 0,045 MPa. Seven Cessna 210 airplane crash locations, two Phantom RF-43 airplane crash locations and one gas explosion load case is modeled. Airplane crash loads were from different directions and to different points of impact in the reactor building. The gas explosion load was assumed to affect the reactor building from one side parallel to one of the global coordinate axes of the model. With MSC/NASTRAN reactions from loads are analyzed. All loads were timedependent; their magnitude varied with time and consequently the analysis was carried out with the aid of transient response analysis. Time step in Cessna 210 analysis was 0,003 s and in Phantom RF-43 and gas explosion analyses 0,01 s. The greatest displacement from Cessna 210 loads was 12 mm and from Phantom RF-43 load 344 mm. The last value shows that construction would fail with that load. The greatest displacement from gas explosion load was 68 mm. Stresses are not so interesting in this preliminary analysis of the effects, but they are shown in pictures embedded in the report text. Displacements were greatest in upper part of the reactor building, where no intersections

  18. Conscientious personality and young drivers’ crash risk

    OpenAIRE

    Ehsani, Johnathon P.; Li, Kaigang; Simons-Morton, Bruce; Tree-McGrath, Cheyenne Fox; Perlus, Jessamyn; O’Brien, Fearghal; Klauer, Sheila G.

    2015-01-01

    Personality characteristics are associated with many risk behaviors. However, the relationship between personality traits, risky driving behavior, and crash risk is poorly understood. The purpose of this study was to examine the association between personality, risky driving behavior, and crashes and near-crashes, using naturalistic driving research methods. Method: Participants' driving exposure, kinematic risky driving (KRD), high-risk secondary task engagement, and the frequency of crashes...

  19. Building concepts against airplane crash

    International Nuclear Information System (INIS)

    Henkel, F.O.; Woelfel, H.

    1984-01-01

    In Germany safety related buildings of nuclear facilities as well as their equipment are to be designed against airplane crash. While the safety of the structure itself can always be guaranteed by structural means, the induced vibrations may cause severe problems for the equipment. Considerable effort was expended in recent years to comprehend the load case airplane crash in a more exact manner and to evaluate reasonable floor response spectra. Besides this analytical effort, investigations are cited to minimize the induced vibrations by new structural concepts. The present paper gives a survey concerning the development of structural concepts, culminating in the double shell structures that are state of the art today. Then the idea of spring supports, as it is known for the aseismic foundation of buildings, is further developed to a new spring concept which reduces the induced vibrations in an optimum way in the load case airplane crash and which additionally isolates earthquake vibrations. (orig.)

  20. Verification Test for Ultra-Light Deployment Mechanism for Sectioned Deployable Antenna Reflectors

    Science.gov (United States)

    Zajac, Kai; Schmidt, Tilo; Schiller, Marko; Seifart, Klaus; Schmalbach, Matthias; Scolamiero, Lucio

    2013-09-01

    The ultra-light deployment mechanism (UDM) is based on three carbon fibre reinforced plastics (CFRP) curved tape springs made of carbon fibre / cyanate ester prepregs.In the frame of the activity its space application suitability for the deployment of solid reflector antenna sections was investigated. A projected diameter of the full reflector of 4 m to 7 m and specific mass in the order of magnitude of 2.6kg/m2 was focused for requirement derivation.Extensive verification tests including health checks, environmental and functional tests were carried out with an engineering model to enable representative characterizing of the UDM unit.This paper presents the design and a technical description of the UDM as well as a summary of achieved development status with respect to test results and possible design improvements.

  1. THE ACCURACY OF AUTOMATIC PHOTOGRAMMETRIC TECHNIQUES ON ULTRA-LIGHT UAV IMAGERY

    Directory of Open Access Journals (Sweden)

    O. Küng

    2012-09-01

    Full Text Available This paper presents an affordable, fully automated and accurate mapping solutions based on ultra-light UAV imagery. Several datasets are analysed and their accuracy is estimated. We show that the accuracy highly depends on the ground resolution (flying height of the input imagery. When chosen appropriately this mapping solution can compete with traditional mapping solutions that capture fewer high-resolution images from airplanes and that rely on highly accurate orientation and positioning sensors on board. Due to the careful integration with recent computer vision techniques, the post processing is robust and fully automatic and can deal with inaccurate position and orientation information which are typically problematic with traditional techniques.

  2. Development of Ultra-Light Composite Material to Build the Platform of a Shaking Table

    Directory of Open Access Journals (Sweden)

    Botero-Jaramillo Eduardo

    2013-10-01

    Full Text Available Based on the developments of the last decades in the area of ultra-light materials, their application in the construction of the platform of the new one direction hydrau- lic shaking table was proposed, with capacity of one ton and frequency range from 0.4 Hz to 4.0 Hz for the Geotechnical Laboratory of the Institute of Engineering, UNAM. The aim was to replace the heavy conventional steel platforms, used in shaking tables, by a composite material based on wood and Kevlar, hence reducing its weight and optimizing the hydraulic equipment capacity available in the labora- tory. Accordingly, an experimental investigation was conducted to characterize the stress-strain behavior of composite materials under monotonically increasing load. This research involved the determination of the adequate proportions of the different constituent materials and manufacturing techniques that best suit the needs and available resources.

  3. Full-Scale Crash Test of an MD-500 Helicopter

    Science.gov (United States)

    Littell, Justin

    2011-01-01

    A full-scale crash test was successfully conducted in March 2010 of an MD-500 helicopter at NASA Langley Research Center s Landing and Impact Research Facility. The reasons for conducting this test were threefold: 1 To generate data to be used with finite element computer modeling efforts, 2 To study the crashworthiness features typically associated with a small representative helicopter, and 3 To compare aircraft response to data collected from a previously conducted MD-500 crash test, which included an externally deployable energy absorbing (DEA) concept. Instrumentation on the airframe included accelerometers on various structural components of the airframe; and strain gages on keel beams, skid gear and portions of the skin. Three Anthropomorphic Test Devices and a specialized Human Surrogate Torso Model were also onboard to collect occupant loads for evaluation with common injury risk criteria. This paper presents background and results from this crash test conducted without the DEA concept. These results showed accelerations of approximately 30 to 50 g on the airframe at various locations, little energy attenuation through the airframe, and moderate to high probability of occupant injury for a variety of injury criteria.

  4. From “Crash!” to Crash: Adapting the Adaptation

    Directory of Open Access Journals (Sweden)

    Ljubica Matek

    2017-12-01

    Full Text Available The paper focuses on J.G. Ballard’s various adaptations of his own material related to the issue of the sexual and sensual nature of an automobile crash, and suggests that adaptation is one of the key methods in art and literature which can be used as a means of contemplating and developing various aesthetic and political ideas. Ballard’s short story “Crash!” was first published in the ICA’s (Institute of Contemporary Arts Eventsheet in February 1969, and later became a chapter of his experimental novel The Atrocity Exhibition (1970. At the same time, Ballard adapts the idea into the “Crashed Cars” exhibition (1970 in London. The short story was then adapted into a short film, Crash!, directed by Harley Cokeliss (1971 and starring Ballard himself, to be finally adapted into the novel Crash (1973. Ballard’s adaptation of his initial ideas across literary forms and media testifies to the importance of adaptation as a process and method of creating art. Thus, rather than suggesting that adaptations merely “breathe life” into the written word, the paper points to the conclusion that the form and content are mutually influential and that, in this case, the novel itself is an adaptation, rather than a hypotext (which it becomes in 1996 to David Cronenberg as he adapts it to film. The complexity of the relationship between the source text and its many adaptations has already contributed to the deconstruction, in Derrida’s terms, of the hierarchy (opposition between the original and the copy. Rather, Ballard’s crossmedial and transmedial adaptations of his own ideas show how, as Ray would suggest, an adaptation cites the source and grafts it into a new context, giving it a new function, both aesthetic and political.

  5. The microburst - Hazard to aircraft

    Science.gov (United States)

    Mccarthy, J.; Serafin, R.

    1984-01-01

    In encounters with microbursts, low altitude aircraft first encounter a strong headwind which increases their wing lift and altitude; this phenomenon is followed in short succession by a decreasing headwind component, a downdraft, and finally a strong tailwind that catastrophically reduces wing lift and precipitates a crash dive. It is noted that the potentially lethal low altitude wind shear of a microburst may lie in apparently harmless, rain-free air beneath a cloud base. Occasionally, such tell-tale signs as localized blowing of ground dust may be sighted in time. Microbursts may, however, occur in the heavy rain of a thunderstorm, where they will be totally obscured from view. Wind shear may be detected by an array of six anemometers and vanes situated in the vicinity of an airport, and by Doppler radar equipment at the airport or aboard aircraft.

  6. Technostress: Surviving a Database Crash.

    Science.gov (United States)

    Dobb, Linda S.

    1990-01-01

    Discussion of technostress in libraries focuses on a database crash at California Polytechnic State University, San Luis Obispo. Steps taken to restore the data are explained, strategies for handling technological accidents are suggested, the impact on library staff is discussed, and a 10-item annotated bibliography on technostress is provided.…

  7. Crash simulations for interior design

    NARCIS (Netherlands)

    Poeze, E.; Slaats, P.M.A.

    1996-01-01

    With the increasing number of compact cars, safety aspects becomes increasingly important for interior designs. The smaller dimensions of these cars do not only decrease the car mass, but also the energy absorption length, resulting in a more severe crash pulse. As a consequence, the inertia loading

  8. 2008 Michigan traffic crash facts

    Science.gov (United States)

    2009-03-18

    In keeping with recent trends, traffic fatalities in 2008 were down to 980, a 9.6 : percent decrease from last year. The total number of persons injured also declined : 7.5 percent to 74,568 and total crashes dropped 2.5 percent to 316,057. Most : no...

  9. 2009 Michigan traffic crash facts

    Science.gov (United States)

    2010-01-01

    In keeping with recent trends, traffic fatalities in 2009 were down to 871, a 11.1 : percent decrease from last year. The total number of persons injured also declined : 4.9 percent to 70,931 and total crashes dropped 7.9 percent to 290,978. Most : n...

  10. Impact of pavement conditions on crash severity.

    Science.gov (United States)

    Li, Yingfeng; Liu, Chunxiao; Ding, Liang

    2013-10-01

    Pavement condition has been known as a key factor related to ride quality, but it is less clear how exactly pavement conditions are related to traffic crashes. The researchers used Geographic Information System (GIS) to link Texas Department of Transportation (TxDOT) Crash Record Information System (CRIS) data and Pavement Management Information System (PMIS) data, which provided an opportunity to examine the impact of pavement conditions on traffic crashes in depth. The study analyzed the correlation between several key pavement condition ratings or scores and crash severity based on a large number of crashes in Texas between 2008 and 2009. The results in general suggested that poor pavement condition scores and ratings were associated with proportionally more severe crashes, but very poor pavement conditions were actually associated with less severe crashes. Very good pavement conditions might induce speeding behaviors and therefore could have caused more severe crashes, especially on non-freeway arterials and during favorable driving conditions. In addition, the results showed that the effects of pavement conditions on crash severity were more evident for passenger vehicles than for commercial vehicles. These results provide insights on how pavement conditions may have contributed to crashes, which may be valuable for safety improvement during pavement design and maintenance. Readers should notice that, although the study found statistically significant effects of pavement variables on crash severity, the effects were rather minor in reality as suggested by frequency analyses. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Reporting on cyclist crashes in Australian newspapers.

    Science.gov (United States)

    Boufous, Soufiane; Aboss, Ahmad; Montgomery, Victoria

    2016-10-01

    To assess information on cyclist crashes reported in Australian newspapers. The Factiva news archive was searched for articles on cyclist crashes published in major Australian newspapers between 2010 and 2013. Information on the circumstances of cyclist crashes were extracted and coded. A total of 160 cyclist crashes were covered by 198 newspaper articles, with 44% of crashes resulting in cyclist fatalities. Crashes reported by more than one newspaper were more likely to involve public figures or protracted court cases. Individual characteristics of cyclists as well as the location of the crash were reported for more than 80% of crashes. The road user at fault was reported for more than half of crashes. In contrast, information on helmet use, alcohol and cycling lanes was mentioned for only about 10% of crashes. Fewer than one in five articles mentioned prevention strategies including education campaigns, legislative and infrastructure changes. Australian newspapers tend to focus on the most dramatic and more 'newsworthy' aspects of cyclist crashes. Cycling advocates need to work with journalists to improve the quality of this coverage. Better communication between cycling advocates and journalists is likely to have a positive impact on the safety and the uptake of cycling in the community. © 2016 Public Health Association of Australia.

  12. Airplane crash simulations

    International Nuclear Information System (INIS)

    Jovall, Ola

    2007-01-01

    Impact loads are considered in nuclear facility design as the result of the loading effects of certain design basis accidents and design basis threats made up of natural as well as man-made hazards. Also, beyond design basis accidents and threats are considered. Typical missiles include objects caused by tornado winds, aircrafts, war or terrorist activities, dropped objects, turbine fragments and other missiles resulting from failure of rotating equipment and whipping pipes and other objects of failure of pressurized fluid systems. The aim of the work is to study the potential of tools for numerical simulations to study the local load effects of airplane missiles impacting concrete structures. Two of the leading commercial computer codes for analysis of highly dynamic events, ABAQUS/Explicit and AUTODYN, have been evaluated. Numerical simulations have been carried out for rigid as well as deformable missiles with the characteristics of airplane engines. The analysis results have been compared with test results from a test program performed in the USA at Sandia National Laboratory and in Japan at Kobori Research Complex and Central Research Institute of the Electric Power industry. Finally, numerical simulations of a large passenger airliner impacting a reactor containment has been carried out using the analysis methodology developed. (author)

  13. Naturalistic Assessment of Novice Teenage Crash Experience

    Science.gov (United States)

    Lee, Suzanne E.; Simons-Morton, Bruce G.; Klauer, Sheila E.; Ouimet, Marie Claude; Dingus, Thomas A.

    2011-01-01

    Background Crash risk is highest during the first months after licensure. Current knowledge about teenagers’ driving exposure and the factors increasing their crash risk is based on self-reported data and crash database analyses. While these research tools are useful, new developments in naturalistic technologies have allowed researchers to examine newly-licensed teenagers’ exposure and crash risk factors in greater detail. The Naturalistic Teenage Driving Study (NTDS) described in this paper is the first study to follow a group of newly-licensed teenagers continuously for 18 months after licensure. The goals of this paper are to compare the crash and near-crash experience of drivers in the NTDS to national trends, to describe the methods and lessons learned in the NTDS, and to provide initial data on driving exposure for these drivers. Methods A data acquisition system was installed in the vehicles of 42 newly-licensed teenage drivers 16 years of age during their first 18 months of independent driving. It consisted of cameras, sensors (accelerometers, GPS, yaw, front radar, lane position, and various sensors obtained via the vehicle network), and a computer with removable hard drive. Data on the driving of participating parents was also collected when they drove the instrumented vehicle. Findings The primary findings after 18 months included the following: (1) crash and near-crash rates among teenage participants were significantly higher during the first six months of the study than the final 12 months, mirroring the national trends; (2) crash and near-crash rates were significantly higher for teenage than adult (parent) participants, also reflecting national trends; (3) teenaged driving exposure averaged between 507-710 kilometers (315-441 miles) per month over the study period, but varied substantially between participants with standard errors representing 8-14 percent of the mean; and (4) crash and near-crash types were very similar for male and female

  14. Effect of Accounting for Crash Severity on the Relationship between Mass Reduction and Crash Frequency and Risk per Crash

    Energy Technology Data Exchange (ETDEWEB)

    Wenzel, Tom P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Building Technology and Urban Systems Division. Energy Technologies Area

    2016-05-20

    Previous analyses have indicated that mass reduction is associated with an increase in crash frequency (crashes per VMT), but a decrease in fatality or casualty risk once a crash has occurred, across all types of light-duty vehicles. These results are counter-intuitive: one would expect that lighter, and perhaps smaller, vehicles have better handling and shorter braking distances, and thus should be able to avoid crashes that heavier vehicles cannot. And one would expect that heavier vehicles would have lower risk once a crash has occurred than lighter vehicles. However, these trends occur under several alternative regression model specifications. This report tests whether these results continue to hold after accounting for crash severity, by excluding crashes that result in relatively minor damage to the vehicle(s) involved in the crash. Excluding non-severe crashes from the initial LBNL Phase 2 and simultaneous two-stage regression models for the most part has little effect on the unexpected relationships observed in the baseline regression models. This finding suggests that other subtle differences in vehicles and/or their drivers, or perhaps biases in the data reported in state crash databases, are causing the unexpected results from the regression models.

  15. High performance supercapacitors based on three-dimensional ultralight flexible manganese oxide nanosheets/carbon foam composites

    Science.gov (United States)

    He, Shuijian; Chen, Wei

    2014-09-01

    The syntheses and capacitance performances of ultralight and flexible MnO2/carbon foam (MnO2/CF) hybrids are systematically studied. Flexible carbon foam with a low mass density of 6.2 mg cm-3 and high porosity of 99.66% is simply obtained by carbonization of commercially available and low-cost melamine resin foam. With the high porous carbon foam as framework, ultrathin MnO2 nanosheets are grown through in situ redox reaction between KMnO4 and carbon foam. The three-dimensional (3D) MnO2/CF networks exhibit highly ordered hierarchical pore structure. Attributed to the good flexibility and ultralight weight, the MnO2/CF nanomaterials can be directly fabricated into supercapacitor electrodes without any binder and conductive agents. Moreover, the pseudocapacitance of the MnO2 nanosheets is enhanced by the fast ion diffusion in the three-dimensional porous architecture and by the conductive carbon foam skeleton as well as good contact of carbon/oxide interfaces. Supercapacitor based on the MnO2/CF composite with 3.4% weight percent of MnO2 shows a high specific capacitance of 1270.5 F g-1 (92.7% of the theoretical specific capacitance of MnO2) and high energy density of 86.2 Wh kg-1. The excellent capacitance performance of the present 3D ultralight and flexible nanomaterials make them promising candidates as electrode materials for supercapacitors.

  16. Illiquidity Contagion and Liquidity Crashes

    OpenAIRE

    Giovanni Cespa; Thierry Foucault

    2014-01-01

    Liquidity providers often learn information about an asset from prices of other assets. We show that this generates a self-reinforcing positive relationship between price informativeness and liquidity. This relationship causes liquidity spillovers and is a source of fragility: a small drop in the liquidity of one asset can, through a feedback loop, result in a very large drop in market liquidity and price informativeness (a liquidity crash). This feedback loop provides a new explanation for c...

  17. Observed and unobserved correlation between crash avoidance manoeuvers and crash severity

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2015-01-01

    Understanding drivers’ responses to critical events, analyzing drivers’ abilities to perform corrective manoeuvers, and investigating the correlation between these manoeuvers and crash severity provide the opportunity of increasing the knowledge about how to avoid crash occurrence or at least mit...

  18. Religion and stock price crash risk: Evidence

    Directory of Open Access Journals (Sweden)

    Wenfei Li

    2016-09-01

    Full Text Available This paper investigates whether religious traditions influence firm-specific crash risk in China. Using a sample of A-share listed firms from 2003 to 2013, we provide evidence that the more intense the religious environment, the lower the stock price crash risk, implying that religion plays an important role in Chinese corporate governance. Further, we find that (1 religion affects stock price crash risk by reducing earnings management and the management perk problem; (2 different religions have different effects, and Taoism, in particular, is unrelated to crash risk; and (3 the effects of religion are more pronounced with higher quality corporate governance and a stronger legal environment. Religion constrains the management agency problem, thus reducing stock price crash risk in China. Our paper enriches the literature on stock price crash risk and religion, and on new economic geography.

  19. Comparison of moped, scooter and motorcycle crash risk and crash severity.

    Science.gov (United States)

    Blackman, Ross A; Haworth, Narelle L

    2013-08-01

    The increased popularity of mopeds and motor scooters in Australia and elsewhere in the last decade has contributed substantially to the greater use of powered two-wheelers (PTWs) as a whole. As the exposure of mopeds and scooters has increased, so too has the number of reported crashes involving those PTW types, but there is currently little research comparing the safety of mopeds and, particularly, larger scooters with motorcycles. This study compared the crash risk and crash severity of motorcycles, mopeds and larger scooters in Queensland, Australia. Comprehensive data cleansing was undertaken to separate motorcycles, mopeds and larger scooters in police-reported crash data covering the five years to 30 June 2008. The crash rates of motorcycles (including larger scooters) and mopeds in terms of registered vehicles were similar over this period, although the moped crash rate showed a stronger downward trend. However, the crash rates in terms of distance travelled were nearly four times higher for mopeds than for motorcycles (including larger scooters). More comprehensive distance travelled data is needed to confirm these findings. The overall severity of moped and scooter crashes was significantly lower than motorcycle crashes but an ordered probit regression model showed that crash severity outcomes related to differences in crash characteristics and circumstances, rather than differences between PTW types per se. Greater motorcycle crash severity was associated with higher (>80km/h) speed zones, horizontal curves, weekend, single vehicle and nighttime crashes. Moped crashes were more severe at night and in speed zones of 90km/h or more. Larger scooter crashes were more severe in 70km/h zones (than 60km/h zones) but not in higher speed zones, and less severe on weekends than on weekdays. The findings can be used to inform potential crash and injury countermeasures tailored to users of different PTW types. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Vehicular crash data used to rank intersections by injury crash frequency and severity

    OpenAIRE

    Liu, Yi; Li, Zongzhi; Liu, Jingxian; Patel, Harshingar

    2016-01-01

    This article contains data on research conducted in “A double standard model for allocating limited emergency medical service vehicle resources ensuring service reliability” (Liu et al., 2016) [1]. The crash counts were sorted out from comprehensive crash records of over one thousand major signalized intersections in the city of Chicago from 2004 to 2010. For each intersection, vehicular crashes were counted by crash severity levels, including fatal, injury Types A, B, and C for major, modera...

  1. Understanding traffic crash under-reporting

    DEFF Research Database (Denmark)

    Janstrup, Kira Hyldekær; Kaplan, Sigal; Hels, Tove

    2016-01-01

    Objective: This study aligns to the body of research dedicated to estimating the underreporting of road crash injuries and adds the perspective of understanding individual and crash factors contributing to the decision to report a crash to the police, the hospital, or both. Method: This study foc...... policy measures aimed at increasing the reporting rate by targeting specific road user groups (e.g., males, young road users) or specific situational factors (e.g., slight injuries, arm injuries, leg injuries, weekend)....

  2. Modelling and mitigation of Flash Crashes

    OpenAIRE

    Fry, John; Serbera, Jean-Philippe

    2017-01-01

    The algorithmic trading revolution has had a dramatic effect upon markets. Trading has become faster, and in some ways more efficient, though potentially at the cost higher volatility and increased uncertainty. Stories of predatory trading and flash crashes constitute a new financial reality. Worryingly, highly capitalised stocks may be particularly vulnerable to flash crashes. Amid fears of high-risk technology failures in the global financial system we develop a model for flash crashes....

  3. Identification of a putative man-made object from an underwater crash site using CAD model superimposition.

    Science.gov (United States)

    Vincelli, Jay; Calakli, Fatih; Stone, Michael; Forrester, Graham; Mellon, Timothy; Jarrell, John

    2018-04-01

    In order to identify an object in video, a comparison with an exemplar object is typically needed. In this paper, we discuss the methodology used to identify an object detected in underwater video that was recorded during an investigation into Amelia Earhart's purported crash site. A computer aided design (CAD) model of the suspected aircraft component was created based on measurements made from orthogonally rectified images of a reference aircraft, and validated against historical photographs of the subject aircraft prior to the crash. The CAD model was then superimposed on the underwater video, and specific features on the object were geometrically compared between the CAD model and the video. This geometrical comparison was used to assess the goodness of fit between the purported object and the object identified in the underwater video. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. AP English language & composition crash course

    CERN Document Server

    Hogue, Dawn

    2012-01-01

    AP English Language & Composition Crash Course - Gets You a Higher Advanced Placement Score in Less Time Crash Course is perfect for the time-crunched student, the last-minute studier, or anyone who wants a refresher on the subject. AP English Language & Composition Crash Course gives you: Targeted, Focused Review - Study Only What You Need to Know Crash Course is based on an in-depth analysis of the AP English Language & Composition course description outline and actual Advanced Placement test questions. It covers only the information tested on the exam, so you can make the most of your valua

  5. AP calculus AB & BC crash course

    CERN Document Server

    Rosebush, J

    2012-01-01

    AP Calculus AB & BC Crash Course - Gets You a Higher Advanced Placement Score in Less Time Crash Course is perfect for the time-crunched student, the last-minute studier, or anyone who wants a refresher on the subject. AP Calculus AB & BC Crash Course gives you: Targeted, Focused Review - Study Only What You Need to Know Crash Course is based on an in-depth analysis of the AP Calculus AB & BC course description outline and actual AP test questions. It covers only the information tested on the exams, so you can make the most of your valuable study time. Written by experienced math teachers, our

  6. Large truck and bus crash facts, 2008. 

    Science.gov (United States)

    2010-03-01

    This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2008. Selected crash statistics on passenger : vehicles are also presen...

  7. A comprehensive engineering analysis of motorcycle crashes in Maryland.

    Science.gov (United States)

    2010-12-01

    The goal of this study was to identify recurring or common road characteristics of motorcycle crashes : in Maryland from 1998 to 2007. Motorcycle crash data was obtained from the National Highway : Traffic Safety Administrations Crash Outcome Data...

  8. 2008 South Dakota motor vehicle traffic crash summary

    Science.gov (United States)

    2009-06-01

    The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2008 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...

  9. 2010 South Dakota motor vehicle traffic crash summary

    Science.gov (United States)

    2011-01-01

    The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical Trends and 2010 Motor Vehicle Traffic Crash Profile. The Historical Trend section provides information on alcohol involvement in motor vehicle crashes, severity of ...

  10. 2009 South Dakota motor vehicle traffic crash summary

    Science.gov (United States)

    2010-06-01

    The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2009 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...

  11. CDC Vital Signs: Motor Vehicle Crash Injuries: Costly but Preventable

    Science.gov (United States)

    ... Press Kit Read the MMWR Science Clips Motor Vehicle Crash Injuries Costly but Preventable Language: English (US) ... and how to prevent future crashes. Problem Motor vehicle crashes are a leading cause of injury in ...

  12. Revisiting the SN1987A gamma-ray limit on ultralight axion-like particles

    Energy Technology Data Exchange (ETDEWEB)

    Payez, Alexandre; Ringwald, Andreas [Theory group, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, D-22607 Hamburg (Germany); Evoli, Carmelo; Mirizzi, Alessandro [II. Institut für Theoretische Physik, Universität Hamburg, Luruper Chaussee 149, D-22761 Hamburg (Germany); Fischer, Tobias [Institute for Theoretical Physics, University of Wroc\\law, Pl. M. Borna 9, 50-204 Wroc\\law (Poland); Giannotti, Maurizio, E-mail: alexandre.payez@desy.de, E-mail: carmelo.evoli@desy.de, E-mail: fischer@ift.uni.wroc.pl, E-mail: mgiannotti@barry.edu, E-mail: alessandro.mirizzi@desy.de, E-mail: andreas.ringwald@desy.de [Physical Sciences, Barry University, 11300 NE 2nd Ave., Miami Shores, FL 33161 (United States)

    2015-02-01

    We revise the bound from the supernova SN1987A on the coupling of ultralight axion-like particles (ALPs) to photons. In a core-collapse supernova, ALPs would be emitted via the Primakoff process, and eventually convert into gamma rays in the magnetic field of the Milky Way. The lack of a gamma-ray signal in the GRS instrument of the SMM satellite in coincidence with the observation of the neutrinos emitted from SN1987A therefore provides a strong bound on their coupling to photons. Due to the large uncertainty associated with the current bound, we revise this argument, based on state-of-the-art physical inputs both for the supernova models and for the Milky-Way magnetic field. Furthermore, we provide major amendments, such as the consistent treatment of nucleon-degeneracy effects and of the reduction of the nuclear masses in the hot and dense nuclear medium of the supernova. With these improvements, we obtain a new upper limit on the photon-ALP coupling: g{sub aγ} ∼< 5.3 × 10{sup -12} GeV{sup -1}, for m{sub a} ∼< 4.4 × 10{sup -10} eV, and we also give its dependence at larger ALP masses m{sub a}. Moreover, we discuss how much the Fermi-LAT satellite experiment could improve this bound, should a close-enough supernova explode in the near future.

  13. Revisiting the SN1987A gamma-ray limit on ultralight axion-like particles

    Energy Technology Data Exchange (ETDEWEB)

    Payez, Alexandre; Ringwald, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Evoli, Carmelo; Mirizzi, Alessandro [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Fischer, Tobias [Wroclaw Univ. (Poland). Inst. for Theoretical Physics; Giannotti, Maurizio [Barry Univ., Miami Shores, FL (United States). Physical Sciences

    2014-10-15

    We revise the bound from the supernova SN1987A on the coupling of ultralight axion-like particles (ALPs) to photons. In a core-collapse supernova, ALPs would be emitted via the Primakoff process, and eventually convert into gamma rays in the magnetic field of the Milky Way. The lack of a gamma-ray signal in the GRS instrument of the SMM satellite in coincidence with the observation of the neutrinos emitted from SN1987A therefore provides a strong bound on their coupling to photons. Due to the large uncertainty associated with the current bound, we revise this argument, based on state-of-the-art physical inputs both for the supernova models and for the Milky-Way magnetic field. Furthermore, we provide major amendments, such as the consistent treatment of nucleon-degeneracy effects and of the reduction of the nuclear masses in the hot and dense nuclear medium of the supernova. With these improvements, we obtain a new upper limit on the photon-ALP coupling: g{sub aγ}

  14. Ultralight and fire-resistant ceramic nanofibrous aerogels with temperature-invariant superelasticity.

    Science.gov (United States)

    Si, Yang; Wang, Xueqin; Dou, Lvye; Yu, Jianyong; Ding, Bin

    2018-04-01

    Ultralight aerogels that are both highly resilient and compressible have been fabricated from various materials including polymer, carbon, and metal. However, it has remained a great challenge to realize high elasticity in aerogels solely based on ceramic components. We report a scalable strategy to create superelastic lamellar-structured ceramic nanofibrous aerogels (CNFAs) by combining SiO 2 nanofibers with aluminoborosilicate matrices. This approach causes the random-deposited SiO 2 nanofibers to assemble into elastic ceramic aerogels with tunable densities and desired shapes on a large scale. The resulting CNFAs exhibit the integrated properties of flyweight densities of >0.15 mg cm -3 , rapid recovery from 80% strain, zero Poisson's ratio, and temperature-invariant superelasticity to 1100°C. The integral ceramic nature also provided the CNFAs with robust fire resistance and thermal insulation performance. The successful synthesis of these fascinating materials may provide new insights into the development of ceramics in a lightweight, resilient, and structurally adaptive form.

  15. Revisiting the SN1987A gamma-ray limit on ultralight axion-like particles

    International Nuclear Information System (INIS)

    Payez, Alexandre; Ringwald, Andreas; Evoli, Carmelo; Mirizzi, Alessandro; Fischer, Tobias; Giannotti, Maurizio

    2014-10-01

    We revise the bound from the supernova SN1987A on the coupling of ultralight axion-like particles (ALPs) to photons. In a core-collapse supernova, ALPs would be emitted via the Primakoff process, and eventually convert into gamma rays in the magnetic field of the Milky Way. The lack of a gamma-ray signal in the GRS instrument of the SMM satellite in coincidence with the observation of the neutrinos emitted from SN1987A therefore provides a strong bound on their coupling to photons. Due to the large uncertainty associated with the current bound, we revise this argument, based on state-of-the-art physical inputs both for the supernova models and for the Milky-Way magnetic field. Furthermore, we provide major amendments, such as the consistent treatment of nucleon-degeneracy effects and of the reduction of the nuclear masses in the hot and dense nuclear medium of the supernova. With these improvements, we obtain a new upper limit on the photon-ALP coupling: g aγ -12 GeV -1 , for m a -10 eV, and we also give its dependence at larger ALP masses m a . Moreover, we discuss how much the Fermi-LAT satellite experiment could improve this bound, should a close-enough supernova explode in the near future.

  16. Amphibious Aircraft

    Data.gov (United States)

    National Aeronautics and Space Administration — A brief self composed research article on Amphibious Aircrafts discussing their use, origin and modern day applications along with their advantages and disadvantages...

  17. Comparison of teen and adult driver crash scenarios in a nationally representative sample of serious crashes.

    Science.gov (United States)

    McDonald, Catherine C; Curry, Allison E; Kandadai, Venk; Sommers, Marilyn S; Winston, Flaura K

    2014-11-01

    Motor vehicle crashes are the leading cause of death and acquired disability during the first four decades of life. While teen drivers have the highest crash risk, few studies examine the similarities and differences in teen and adult driver crashes. We aimed to: (1) identify and compare the most frequent crash scenarios-integrated information on a vehicle's movement prior to crash, immediate pre-crash event, and crash configuration-for teen and adult drivers involved in serious crashes, and (2) for the most frequent scenarios, explore whether the distribution of driver critical errors differed for teens and adult drivers. We analyzed data from the National Motor Vehicle Crash Causation Survey, a nationally representative study of serious crashes conducted by the U.S. National Highway Traffic Safety Administration from 2005 to 2007. Our sample included 642 16- to 19-year-old and 1167 35- to 54-year-old crash-involved drivers (weighted n=296,482 and 439,356, respectively) who made a critical error that led to their crash's critical pre-crash event (i.e., event that made the crash inevitable). We estimated prevalence ratios (PR) and 95% confidence intervals (CI) to compare the relative frequency of crash scenarios and driver critical errors. The top five crash scenarios among teen drivers, accounting for 37.3% of their crashes, included: (1) going straight, other vehicle stopped, rear end; (2) stopped in traffic lane, turning left at intersection, turn into path of other vehicle; (3) negotiating curve, off right edge of road, right roadside departure; (4) going straight, off right edge of road, right roadside departure; and (5) stopped in lane, turning left at intersection, turn across path of other vehicle. The top five crash scenarios among adult drivers, accounting for 33.9% of their crashes, included the same scenarios as the teen drivers with the exception of scenario (3) and the addition of going straight, crossing over an intersection, and continuing on a

  18. Assessment of aircraft impact probabilities at the Idaho Chemical Processing Plant

    International Nuclear Information System (INIS)

    Lee, L.G.; Mines, J.M.; Webb, B.B.

    1996-04-01

    The purpose of this study is to evaluate the possibility of an aircraft crash into a facility at the Idaho Chemical Processing Plant (ICPP). The ICPP is part of the Idaho National Engineering Laboratory (INEL). Based on the data used in this study, an air crash into any single facility at the ICPP is incredible, An air crash into aggregate areas incorporating the following is extremely unlikely: (1) ICPP radiological materials storage facilities, (2) ICPP major processing facilities, and (3) the ICPP total surface area. The radiological materials storage facilities aggregate areas are areas of concern usually requiring safety analyses, According to Department of Energy guidance, if the probability of a radiological release event is determined to be incredible, no further review is required. No individual facility in this analysis has a crash potential large enough to be credible. Therefore, an aircraft crash scenario is not required in the safety analysis for a single facility, but should be discussed relative to the ICPP aggregate areas, The highest probability of concern in the study was for aircraft to crash into the aggregate area for radiological materials storage facilities at the ICPP during Federal Aviation Administration (FAA) test flights

  19. Specific problems concerning aircraft impact on nuclear containment vessels

    International Nuclear Information System (INIS)

    Fuzier, J.P.; Cheyrezy, M.H.; Dufour, C.J.

    1977-01-01

    Due to the high population density, in Belgium PWR power plants are designed against aircraft impacts (BOEING 707 crashing at 360 km per hour and STARFIGHTER F 104 G crashing at 540 km per hour). A double wall is used for the containment shield. The lack of relevant data and specifications for such a loading on the non-prestressed external wall led the authors to determine the suitable safety criteria, the most appropriate materials to be used and the corresponding limit state design through dynamic and plastic analysis. (Auth.)

  20. Predicting motorcycle crash injury severity using weather data and alternative Bayesian multivariate crash frequency models.

    Science.gov (United States)

    Cheng, Wen; Gill, Gurdiljot Singh; Sakrani, Taha; Dasu, Mohan; Zhou, Jiao

    2017-11-01

    Motorcycle crashes constitute a very high proportion of the overall motor vehicle fatalities in the United States, and many studies have examined the influential factors under various conditions. However, research on the impact of weather conditions on the motorcycle crash severity is not well documented. In this study, we examined the impact of weather conditions on motorcycle crash injuries at four different severity levels using San Francisco motorcycle crash injury data. Five models were developed using Full Bayesian formulation accounting for different correlations commonly seen in crash data and then compared for fitness and performance. Results indicate that the models with serial and severity variations of parameters had superior fit, and the capability of accurate crash prediction. The inferences from the parameter estimates from the five models were: an increase in the air temperature reduced the possibility of a fatal crash but had a reverse impact on crashes of other severity levels; humidity in air was not observed to have a predictable or strong impact on crashes; the occurrence of rainfall decreased the possibility of crashes for all severity levels. Transportation agencies might benefit from the research results to improve road safety by providing motorcyclists with information regarding the risk of certain crash severity levels for special weather conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Crash-Tech 2001. Conference; Crash-Tech 2001. Tagung

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Improved active and passive safety of motor vehicles has resulted in a very much improved accident statistics. This conference discussed further optimisations in motor car safety. The harmonisation of test specifications world-wide was gone into, with particular interest in compatibility. Safety specifications resulting from current accident research and new legislation were gone into, and the current state of measuring and technology in crash testing was outlined. [German] Aufgrund der Verbesserungen in der aktiven und passiven Sicherheit von Fahrzeugen weisen die Unfallstatistiken in vielen europaeischen Laendern eine erfreuliche Tendenz auf. Die Tagung wird sich mit den Moeglichkeiten der weiteren Optimierung der Verkehrssicherheit befassen. Die 'Crash-Tech 2001' will sich mit dem Motto 'Sind wir auf dem Weg zum World NCAP?' der Harmonisierung der Testvorschriften unter Einbeziehung der Kompatibilitaet widmen. Dazu werden Anforderungen an die Fahrzeugsicherheit diskutiert, die sich sowohl aus der aktuellen Unfallforschung als auch aus den Vorschriften ergeben. Weiterhin wird der aktuelle Stand der Mess- und Versuchstechnik im Unfallversuch vorgestellt. (orig.)

  2. System crash as dynamics of complex networks.

    Science.gov (United States)

    Yu, Yi; Xiao, Gaoxi; Zhou, Jie; Wang, Yubo; Wang, Zhen; Kurths, Jürgen; Schellnhuber, Hans Joachim

    2016-10-18

    Complex systems, from animal herds to human nations, sometimes crash drastically. Although the growth and evolution of systems have been extensively studied, our understanding of how systems crash is still limited. It remains rather puzzling why some systems, appearing to be doomed to fail, manage to survive for a long time whereas some other systems, which seem to be too big or too strong to fail, crash rapidly. In this contribution, we propose a network-based system dynamics model, where individual actions based on the local information accessible in their respective system structures may lead to the "peculiar" dynamics of system crash mentioned above. Extensive simulations are carried out on synthetic and real-life networks, which further reveal the interesting system evolution leading to the final crash. Applications and possible extensions of the proposed model are discussed.

  3. Aircraft Carriers

    DEFF Research Database (Denmark)

    Nødskov, Kim; Kværnø, Ole

    as their purchases of aircraft carrier systems, makes it more than likely that the country is preparing such an acquisition. China has territorial disputes in the South China Sea over the Spratly Islands and is also worried about the security of its sea lines of communications, by which China transports the majority......, submarines, aircraft and helicopters, is not likely to be fully operational and war-capable until 2020, given the fact that China is starting from a clean sheet of paper. The United States of America (USA), the United Kingdom (UK), Russia and India are currently building or have made decisions to build new...

  4. Crash data modeling with a generalized estimator.

    Science.gov (United States)

    Ye, Zhirui; Xu, Yueru; Lord, Dominique

    2018-05-11

    The investigation of relationships between traffic crashes and relevant factors is important in traffic safety management. Various methods have been developed for modeling crash data. In real world scenarios, crash data often display the characteristics of over-dispersion. However, on occasions, some crash datasets have exhibited under-dispersion, especially in cases where the data are conditioned upon the mean. The commonly used models (such as the Poisson and the NB regression models) have associated limitations to cope with various degrees of dispersion. In light of this, a generalized event count (GEC) model, which can be generally used to handle over-, equi-, and under-dispersed data, is proposed in this study. This model was first applied to case studies using data from Toronto, characterized by over-dispersion, and then to crash data from railway-highway crossings in Korea, characterized with under-dispersion. The results from the GEC model were compared with those from the Negative binomial and the hyper-Poisson models. The cases studies show that the proposed model provides good performance for crash data characterized with over- and under-dispersion. Moreover, the proposed model simplifies the modeling process and the prediction of crash data. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Aircraft cybernetics

    Science.gov (United States)

    1977-01-01

    The use of computers for aircraft control, flight simulation, and inertial navigation is explored. The man-machine relation problem in aviation is addressed. Simple and self-adapting autopilots are described and the assets and liabilities of digital navigation techniques are assessed.

  6. Factors Contributing to Crashes among Young Drivers

    Directory of Open Access Journals (Sweden)

    Lyndel J. Bates

    2014-08-01

    Full Text Available Young drivers are the group of drivers most likely to crash. There are a number of factors that contribute to the high crash risk experienced by these drivers. While some of these factors are intrinsic to the young driver, such as their age, gender or driving skill, others relate to social factors and when and how often they drive. This article reviews the factors that affect the risk of young drivers crashing to enable a fuller understanding of why this risk is so high in order to assist in developing effective countermeasures.

  7. Braking News: the Link between Crash Severity and Crash Avoidance Maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    the ordered-response nature of severity while allowing for changes in effects across severity levels. The data sample for estimation consists of single-vehicle crashes extracted from the General Estimates System (GES) crash database for the period 2005-2009. Results show the correlation between crash...... severity. These trends suggest that effort should be posed toward understanding the reaction mechanisms to different critical events, improving in-vehicle warning systems, promoting responsible driving behavior, and designing forgiving infrastructures....

  8. MITEE: A Compact Ultralight Nuclear Thermal Propulsion Engine for Planetary Science Missions

    Science.gov (United States)

    Powell, J.; Maise, G.; Paniagua, J.

    2001-01-01

    A new approach for a near-term compact, ultralight nuclear thermal propulsion engine, termed MITEE (Miniature Reactor Engine) is described. MITEE enables a wide range of new and unique planetary science missions that are not possible with chemical rockets. With U-235 nuclear fuel and hydrogen propellant the baseline MITEE engine achieves a specific impulse of approximately 1000 seconds, a thrust of 28,000 newtons, and a total mass of only 140 kilograms, including reactor, controls, and turbo-pump. Using higher performance nuclear fuels like U-233, engine mass can be reduced to as little as 80 kg. Using MITEE, V additions of 20 km/s for missions to outer planets are possible compared to only 10 km/s for H2/O2 engines. The much greater V with MITEE enables much faster trips to the outer planets, e.g., two years to Jupiter, three years to Saturn, and five years to Pluto, without needing multiple planetary gravity assists. Moreover, MITEE can utilize in-situ resources to further extend mission V. One example of a very attractive, unique mission enabled by MITEE is the exploration of a possible subsurface ocean on Europa and the return of samples to Earth. Using MITEE, a spacecraft would land on Europa after a two-year trip from Earth orbit and deploy a small nuclear heated probe that would melt down through its ice sheet. The probe would then convert to a submersible and travel through the ocean collecting samples. After a few months, the probe would melt its way back up to the MITEE lander, which would have replenished its hydrogen propellant by melting and electrolyzing Europa surface ice. The spacecraft would then return to Earth. Total mission time is only five years, starting from departure from Earth orbit. Other unique missions include Neptune and Pluto orbiter, and even a Pluto sample return. MITEE uses the cermet Tungsten-UO2 fuel developed in the 1960's for the 710 reactor program. The W-UO2 fuel has demonstrated capability to operate in 3000 K hydrogen for

  9. Large Truck Crash Causation Study (LTCCS)

    Data.gov (United States)

    Department of Transportation — The Large Truck* Crash Causation Study (LTCCS) is based on a three-year data collection project conducted by the Federal Motor Carrier Safety Administration (FMCSA)...

  10. Economic Cost of Crashes in Idaho

    Science.gov (United States)

    2016-06-01

    The Idaho Transportation Departments Office of Highway Safety contracted with Cambridge Systematics (CS) for an assessment of the feasibility of calculating the Idaho-specific economic and comprehensive costs associated with vehicle crashes. Resea...

  11. Motor Vehicle Crash Injuries PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    This 60 second Public Service Announcement is based on the October 2014 CDC Vital Signs report. Motor vehicle crashes are costly and preventable. Learn what can be done to help prevent motor vehicle injuries.

  12. Exploring cycle crash characteristics in Malaysia

    Directory of Open Access Journals (Sweden)

    Hamzah A.

    2017-01-01

    Full Text Available This paper explains the cycle road crash trend, characteristics and injuries in Malaysia. It analyses the in-depth road crash investigation data collected by the Royal Malaysian Police which was made available to MIROS crash database. Fatality data was utilized due to its consistency. Cycle casualties reflected a continual downward pattern for year 2009 to 2014 in which the number of cycle crash involvement reduced by 49% and fatalities dropped by 42%. Among the prevalent factors of cycle fatalities are >60 age group, federal and state roads and straight road sections, rural and small towns, evening peak hours, and mainly involving cars and motorcycles. It is hoped that all these information would spark interests to improve cycle safety in Malaysia.

  13. Syncope and Motor Vehicle Crash Risk

    DEFF Research Database (Denmark)

    Numé, Anna-Karin; Gislason, Gunnar; Christiansen, Christine Benn

    2016-01-01

    IMPORTANCE: Syncope may have serious consequences for traffic safety. Current clinical guideline recommendations on driving following syncope are primarily based on expert consensus. OBJECTIVE: To identify whether there is excess risk of motor vehicle crashes among patients with syncope compared...... vehicle crashes throughout the follow-up period. This study suggests that syncope should be considered as one of several factors in a broad assessment of fitness to drive....

  14. Multinational Corporations and Stock Price Crash Risk

    Directory of Open Access Journals (Sweden)

    Anthony May

    2016-10-01

    Full Text Available A nascent literature in finance and accounting on tail risk in individual stock returns concludes that bad news hoarding by corporate managers engenders sudden, extreme crashes in a firm’s stock price when the bad news is eventually made public. This literature finds that firm-specific crash risk is higher among firms with more severe asymmetric information and agency problems. A hitherto disjointed literature spanning the fields of international business, finance, and accounting suggests that geographic dispersion in a firm’s operations, and especially dispersion across different countries, gives rise to organizational complexities and greater costs of monitoring that can exacerbate asymmetric information and agency problems. Motivated by the confluence of arguments and findings from these two strands of literature, this paper examines whether stock price crash risk is higher among multinational firms than domestic firms. Using a large sample of U.S. headquartered firms during 1987-2011, we find robust evidence that multinational firms are significantly more likely to crash than domestic firms. Moreover, we show that the difference in crash risk between multinational and domestic firms is most acute among firms with weaker corporate governance mechanisms, including weaker shareholder rights, less independent boards, and less stable institutional ownership. Our analysis indicates that stronger monitoring from each of these three governance mechanisms significantly attenuates the positive relation between crash risk and multinationality. Our findings are robust to the use of alternative measures of crash risk and to controlling for known determinants of crash risk identified in prior studies. Our study offers new insights that should hold value for scholars and market participants interested in understanding the implications of heighted agency problems that multinational firms are likely to encounter and scholars and market participants

  15. The design of nuclear power plants in the Federal Republic of Germany as regards aircraft accidents

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    On the basis of investigation results of aircraft crashes for the Federal territory and site assessment data of the Ministry of the Interior, air traffic does not present a notable hazard for a nuclear power plant. As a precautionary measure for reducing the remaining risk, design requirements for LWRs were developed which, independently of existing aircraft types, contain mainly an abstract predetermination of an idealized impact load - time diagramme. (HP) [de

  16. Relationship of Near-Crash/Crash Risk to Time Spent on a Cell Phone While Driving.

    Science.gov (United States)

    Farmer, Charles M; Klauer, Sheila G; McClafferty, Julie A; Guo, Feng

    2015-01-01

    The objective of this study was to examine in a naturalistic driving setting the dose-response relationship between cell phone usage while driving and risk of a crash or near crash. How is the increasing use of cell phones by drivers associated with overall near-crash/crash risk (i.e., during driving times both on and off the phone)? Day-to-day driving behavior of 105 volunteer subjects was monitored over a period of 1 year. A random sample was selected comprised of 4 trips from each month that each driver was in the study, and in-vehicle video was used to classify driver behavior. The proportion of driving time spent using a cell phone was estimated for each 3-month period and correlated with overall crash and near-crash rates for each period. Thus, it was possible to test whether changes in an individual driver's cell phone use over time were associated with changes in overall near-crash/crash risk. Drivers in the study spent 11.7% of their driving time interacting with a cell phone, primarily talking on the phone (6.5%) or simply holding the phone in their hand or lap (3.7%). The risk of a near-crash/crash event was approximately 17% higher when the driver was interacting with a cell phone, due primarily to actions of reaching for/answering/dialing, which nearly triples risk (relative risk = 2.84). However, the amount of driving time spent interacting with a cell phone did not affect a driver's overall near-crash/crash risk. Vehicle speeds within 6 s of the beginning of each call on average were 5-6 mph lower than speeds at other times. Results of this naturalistic driving study are consistent with the observation that increasing cell phone use in the general driving population has not led to increased crash rates. Although cell phone use can be distracting and crashes have occurred during this distraction, overall crash rates appear unaffected by changes in the rate of cell phone use, even for individual drivers. Drivers compensate somewhat for the distraction

  17. The trend of road traffic crashes at urban signalised intersection

    Science.gov (United States)

    Farhana Nasarrudin, Nurul; Razelan, Intan Suhana Mohd

    2018-04-01

    Road traffic crash is one of the main contributing factors for deaths in the world. Intersection is listed as the second road type which road crashes occurred frequently. Hence, the traffic light was installed to minimise the road crashes at intersection. However, the crashes are still occurring and arising. The objective of this study was to exhibit the trend of road crashes at the signalised intersections. The data of road crashes for the past 6 years were analysed using descriptive analysis. The results showed that the road traffic crashes at three- and four-legged signalised intersection recorded the increasing trend. In conclusion, this finding shows that the road traffic crashes for these types of signalised intersection in Malaysia is rising. It is also one the contributors to the increasing number of crashes in Malaysia. This finding will encourage the local authority to conduct awareness programs on the safety at the signalised intersection.

  18. Risk assessment of aircraft accidents anywhere near an airport

    International Nuclear Information System (INIS)

    Barbaran, Gustavo; Jensen Mariani Santiago Nicolas

    2011-01-01

    This work analyzes the more suitable areas to build new facilities, taking into account the conditions imposed by an airport located nearby. Initially, it describes the major characteristics of the airport. Then, the restrictions imposed to ensure the normal operation of the aircraft are analyzed. Following, there is a summary of the evolution of studies of aircraft accidents at nuclear facilities. In the second part, three models of aircraft crash probabilities are presented, all of them developed in the U.S.A, each with an increasing level of complexity in modeling the likelihood of accidents. The first model is the 'STD-3014' Department of Energy (DOE), the second is the 'ACRAM'(Aircraft Crash Risk Assessment Methodology) prepared by the 'Lawrence Livermore National Laboratory'(LLNL) and finally the more advanced 'ACRP-3', produced by the 'Transportation Research Board'. The results obtained with the three models establish that the risks imposed on the airport vicinity, remain low due to the improvement and innovation in the aircraft's safety, reducing the risk margin for the location of new nuclear facilities near an airport. (author) [es

  19. Crash test rating and likelihood of major thoracoabdominal injury in motor vehicle crashes: the new car assessment program side-impact crash test, 1998-2010.

    Science.gov (United States)

    Figler, Bradley D; Mack, Christopher D; Kaufman, Robert; Wessells, Hunter; Bulger, Eileen; Smith, Thomas G; Voelzke, Bryan

    2014-03-01

    The National Highway Traffic Safety Administration's New Car Assessment Program (NCAP) implemented side-impact crash testing on all new vehicles since 1998 to assess the likelihood of major thoracoabdominal injuries during a side-impact crash. Higher crash test rating is intended to indicate a safer car, but the real-world applicability of these ratings is unknown. Our objective was to determine the relationship between a vehicle's NCAP side-impact crash test rating and the risk of major thoracoabdominal injury among the vehicle's occupants in real-world side-impact motor vehicle crashes. The National Automotive Sampling System Crashworthiness Data System contains detailed crash and injury data in a sample of major crashes in the United States. For model years 1998 to 2010 and crash years 1999 to 2010, 68,124 occupants were identified in the Crashworthiness Data System database. Because 47% of cases were missing crash severity (ΔV), multiple imputation was used to estimate the missing values. The primary predictor of interest was the occupant vehicle's NCAP side-impact crash test rating, and the outcome of interest was the presence of major (Abbreviated Injury Scale [AIS] score ≥ 3) thoracoabdominal injury. In multivariate analysis, increasing NCAP crash test rating was associated with lower likelihood of major thoracoabdominal injury at high (odds ratio [OR], 0.8; 95% confidence interval [CI], 0.7-0.9; p NCAP side-impact crash test rating is associated with a lower likelihood of major thoracoabdominal trauma. Epidemiologic study, level III.

  20. Vehicular crash data used to rank intersections by injury crash frequency and severity

    Directory of Open Access Journals (Sweden)

    Yi Liu

    2016-09-01

    Full Text Available This article contains data on research conducted in “A double standard model for allocating limited emergency medical service vehicle resources ensuring service reliability” (Liu et al., 2016 [1]. The crash counts were sorted out from comprehensive crash records of over one thousand major signalized intersections in the city of Chicago from 2004 to 2010. For each intersection, vehicular crashes were counted by crash severity levels, including fatal, injury Types A, B, and C for major, moderate, and minor injury levels, property damage only (PDO, and unknown. The crash data was further used to rank intersections by equivalent injury crash frequency. The top 200 intersections with the highest number of crash occurrences identified based on crash frequency- and severity-based scenarios are shared in this brief. The provided data would be a valuable source for research in urban traffic safety analysis and could also be utilized to examine the effectiveness of traffic safety improvement planning and programming, intersection design enhancement, incident and emergency management, and law enforcement strategies.

  1. Barrier-relevant crash modification factors and average costs of crashes on arterial roads in Indiana.

    Science.gov (United States)

    Zou, Yaotian; Tarko, Andrew P

    2018-02-01

    The objective of this study was to develop crash modification factors (CMFs) and estimate the average crash costs applicable to a wide range of road-barrier scenarios that involved three types of road barriers (concrete barriers, W-beam guardrails, and high-tension cable barriers) to produce a suitable basis for comparing barrier-oriented design alternatives and road improvements. The intention was to perform the most comprehensive and in-depth analysis allowed by the cross-sectional method and the crash data available in Indiana. To accomplish this objective and to use the available data efficiently, the effects of barrier were estimated on the frequency of barrier-relevant (BR) crashes, the types of harmful events and their occurrence during a BR crash, and the severity of BR crash outcomes. The harmful events component added depth to the analysis by connecting the crash onset with its outcome. Further improvement of the analysis was accomplished by considering the crash outcome severity of all the individuals involved in a crash and not just drivers, utilizing hospital data, and pairing the observations with and without road barriers along same or similar road segments to better control the unobserved heterogeneity. This study confirmed that the total number of BR crashes tended to be higher where medians had installed barriers, mainly due to collisions with barriers and, in some cases, with other vehicles after redirecting vehicles back to traffic. These undesirable effects of barriers were surpassed by the positive results of reducing cross-median crashes, rollover events, and collisions with roadside hazards. The average cost of a crash (unit cost) was reduced by 50% with cable barriers installed in medians wider than 50ft. A similar effect was concluded for concrete barriers and guardrails installed in medians narrower than 50ft. The studied roadside guardrails also reduced the unit cost by 20%-30%. Median cable barriers were found to be the most effective

  2. Aircraft accident analysis for emergency planning and safety analysis

    International Nuclear Information System (INIS)

    Nicolosi, S.L.; Jordan, H.; Foti, D.; Mancuso, J.

    1996-01-01

    Potential aircraft accidents involving facilities at the Rocky Flats Environmental Technology Site (Site) are evaluated to assess their safety significance. This study addresses the probability and facility penetrability of aircraft accidents at the Site. The types of aircraft (large, small, etc.) that may credibly impact the Site determine the types of facilities that may be breached. The methodology used in this analysis follows elements of the draft Department of Energy Standard ''Accident Analysis for Aircraft Crash into Hazardous Facilities'' (July 1995). Key elements used are: the four-factor frequency equation for aircraft accidents; the distance criteria for consideration of airports, airways, and jet routes; the consideration of different types of aircraft; and the Modified National Defense Research Committee (NDRC) formula for projectile penetration, perforation, and minimum resistant thickness. The potential aircraft accident frequency for each type of aircraft applicable to the Site is estimated using a four-factor formula described in the draft Standard. The accident frequency is the product of the annual number of operations, probability of an accident, probability density function, and area. The annual number of operations is developed from site-specific and state-wide data

  3. InPhoCUS (Inflated Photovoltaic Ultra-light Mirror Concentrators): First Results Of The Project And Future Perspectives

    Science.gov (United States)

    Pravettoni, Mauro; Barbato, Maurizio; Cooper, Thomas; Pedretti, Andrea; Ambrosetti, Gianluca; Steinfeld, Aldo

    2011-12-01

    InPhoCUS (Inflated PhotovoltaiC Ultra-light mirror concentratorS) is a concentrating photovoltaic (CPV) project funded by the Swiss Confederation's Innovation Promotion Agency (CTI) and developed by Airlight Energy Holding SA, the University of Applied Sciences and Arts of Southern Switzerland and the Swiss Federal Institute of Technology. The proposed novel concentrating system has already been patented for concentrated solar power applications: it is made by unconventional pneumatic multilayer polymeric mirrors, has an innovative fibre-reinforced concrete structure and an original tilting mechanism to track the sun. The innovative CPV solar collector is profitable for electric power plants both for the sun-belt region and in the Mediterranean. In this paper the authors present the novel CPV system and preliminary results on cost analysis, optical design and thermal modelling.

  4. Development of ultra-light pixelated systems based on CMOS sensors for future high precision vertex detectors

    Energy Technology Data Exchange (ETDEWEB)

    Winter, Marc [Institut Pluridisciplinaire Hubert Curien - IPHC, 23 rue du loess - BP28, 67037 Strasbourg cedex 2 (France)

    2010-07-01

    CMOS pixel sensors have demonstrated attractive performances in terms of spatial resolution and material budget. The recent emergence of high resistivity substrates in mass production CMOS processes has originated particularly high signal-to-noise ratios and improved the non-ionising radiation tolerance to fluences close to 10{sup 14} Neq/cm{sup 2}. These achievements, obtained with MIMOSA sensors developed at IPHC (Strasbourg) and IRFU (Saclay) will be overviewed and put in perspective of the numerous applications of the sensors. These include collider experiments at RHIC, LHC, ILC and CLIC. The development of ultra-light ladders composed of these sensors and featuring 0.1% to 0.3% of radiation length, will be summarised. The contribution to the conference will also address the evolution of these pixelated systems, including on-going R on multi-tier sensors exploiting vertical integration technologies. (author)

  5. Daedalus Project's Light Eagle - Human powered aircraft

    Science.gov (United States)

    1987-01-01

    autopilot that could be used on high altitude or human powered aircraft, and determining the power required to fly the Daedalus aircraft. The research flights began in late December 1987 with a shake-down of the Light Eagle instrumentation and data transfer links. The first flight of the Daedalus 87 also occurred during this time. On February 7, 1988, the Daedalus 87 aircraft crashed on Rogers Dry Lakebed. The Daedalus 88, which later set the world record, was then shipped from MIT to replace the 87's research flights, and for general checkout procedures. Due to the accident, flight testing was extended four weeks and thus ended in mid-March 1988 after having achieved the major goals of the program; exploring the dynamics of low Reynolds number aircraft, and investigating the aeroelastic behavior of lightweight aircraft. The information obtained from this program had direct applications to the later design of many high-altitude, long endurance aircraft.

  6. Examination of factors associated in motorcycle crashes in work zones.

    Science.gov (United States)

    2013-01-01

    This paper analyzes the factors associated with motorcycle crashes in work zones. This analysis was completed : through the collection and inspection of three types of data: 1) practices used throughout the country on this topic, : 2) crash reports a...

  7. Financial Services Advertising before and after the Crash of 1987.

    Science.gov (United States)

    Everett, Stephen E.

    1988-01-01

    Examines institutional changes in advertising before and after the stock market "crash" of 1987 as represented in the "Wall Street Journal." Finds that financial institutions increased the frequency and size of ads after the crash. (RS)

  8. School start times and teenage driver motor vehicle crashes.

    Science.gov (United States)

    2015-12-01

    There is substantial evidence that lack of sleep is a significant factor in motor vehicle crashes experienced by teenage drivers. This report examines the hypothesis that a later high school start time may reduce crash rates by reducing the interfere...

  9. Linear regression crash prediction models : issues and proposed solutions.

    Science.gov (United States)

    2010-05-01

    The paper develops a linear regression model approach that can be applied to : crash data to predict vehicle crashes. The proposed approach involves novice data aggregation : to satisfy linear regression assumptions; namely error structure normality ...

  10. Risk factors associated with high potential for serious crashes.

    Science.gov (United States)

    2015-09-01

    Crashes are random events and low traffic volumes therefore dont always make crash hot-spot : identification possible. This project has used extensive data collection and analysis for a large sample : of Oregons low volume roads to develop a ri...

  11. Taxonomy of Older Driver Behaviors and Crash Risk : Appendix C

    Science.gov (United States)

    2012-02-01

    This projects objectives were to identify risky behaviors, driving habits, and exposure patterns that have been shown to increase the likelihood of crash involvement among older drivers; and to classify these crash-contributing factors according t...

  12. Evaluation of safety ratings of roads based on frontal crashes with known crash pulse and injury outcome.

    Science.gov (United States)

    Stigson, H

    2009-06-01

    The objective in this study, using data from crashed cars fitted with on-board crash pulse recorders, was to present differences in average crash severity, distribution of crash severity, and injury outcomes, based on an independent safety rating of roads, also taking road type and speed limit into consideration. Furthermore, the objective was to evaluate differences in injury risk, based on the distribution of crash severity. The investigation included both frontal two-vehicle crashes and single-vehicle crashes with known injury outcome. In total, 209 real-world crashes involving cars fitted with crash pulse recorders were included. For all crashes, average mean acceleration and change of velocity of the vehicle acceleration pulse were measured and calculated. All crash spots were classified according to an independent road safety rating program (European Road Assessment Programme Road Protection Score), where the safety quality of roads is rated in relation to posted speed limits. The crash severity and injury outcome in crashes that occurred on roads with good safety ratings were compared with crashes on roads with poor safety ratings. The data were also divided into subcategories according to posted speed limit and road type, to evaluate whether there was a difference in crash severity and injury outcome within the categories. In total, crash severity was statistically significantly lower in crashes occurring on roads with good safety ratings than in crashes occurring on roads with poor safety ratings. It was found that crash severity and injury risk were lower on roads with good safety ratings with a speed limit of above 90 km/h compared with roads with poor safety ratings, irrespective of speed limit. On the other hand, crash severity was higher on roads with good safety ratings with speed limit of 70 km/h than on roads with poor safety ratings with the same speed limit. Though it was found that a higher speed limit resulted in higher crash severity on roads

  13. Modeling Programs Increase Aircraft Design Safety

    Science.gov (United States)

    2012-01-01

    Flutter may sound like a benign word when associated with a flag in a breeze, a butterfly, or seaweed in an ocean current. When used in the context of aerodynamics, however, it describes a highly dangerous, potentially deadly condition. Consider the case of the Lockheed L-188 Electra Turboprop, an airliner that first took to the skies in 1957. Two years later, an Electra plummeted to the ground en route from Houston to Dallas. Within another year, a second Electra crashed. In both cases, all crew and passengers died. Lockheed engineers were at a loss as to why the planes wings were tearing off in midair. For an answer, the company turned to NASA s Transonic Dynamics Tunnel (TDT) at Langley Research Center. At the time, the newly renovated wind tunnel offered engineers the capability of testing aeroelastic qualities in aircraft flying at transonic speeds near or just below the speed of sound. (Aeroelasticity is the interaction between aerodynamic forces and the structural dynamics of an aircraft or other structure.) Through round-the-clock testing in the TDT, NASA and industry researchers discovered the cause: flutter. Flutter occurs when aerodynamic forces acting on a wing cause it to vibrate. As the aircraft moves faster, certain conditions can cause that vibration to multiply and feed off itself, building to greater amplitudes until the flutter causes severe damage or even the destruction of the aircraft. Flutter can impact other structures as well. Famous film footage of the Tacoma Narrows Bridge in Washington in 1940 shows the main span of the bridge collapsing after strong winds generated powerful flutter forces. In the Electra s case, faulty engine mounts allowed a type of flutter known as whirl flutter, generated by the spinning propellers, to transfer to the wings, causing them to vibrate violently enough to tear off. Thanks to the NASA testing, Lockheed was able to correct the Electra s design flaws that led to the flutter conditions and return the

  14. Pre-crash scenarios at road junctions: A clustering method for car crash data.

    Science.gov (United States)

    Nitsche, Philippe; Thomas, Pete; Stuetz, Rainer; Welsh, Ruth

    2017-10-01

    Given the recent advancements in autonomous driving functions, one of the main challenges is safe and efficient operation in complex traffic situations such as road junctions. There is a need for comprehensive testing, either in virtual simulation environments or on real-world test tracks. This paper presents a novel data analysis method including the preparation, analysis and visualization of car crash data, to identify the critical pre-crash scenarios at T- and four-legged junctions as a basis for testing the safety of automated driving systems. The presented method employs k-medoids to cluster historical junction crash data into distinct partitions and then applies the association rules algorithm to each cluster to specify the driving scenarios in more detail. The dataset used consists of 1056 junction crashes in the UK, which were exported from the in-depth "On-the-Spot" database. The study resulted in thirteen crash clusters for T-junctions, and six crash clusters for crossroads. Association rules revealed common crash characteristics, which were the basis for the scenario descriptions. The results support existing findings on road junction accidents and provide benchmark situations for safety performance tests in order to reduce the possible number parameter combinations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Bubbles, Post-Crash Dynamics, and the Housing Market

    OpenAIRE

    Crocker H. Liu; Adam Nowak; Stuart Rosenthal

    2014-01-01

    This paper documents and explains previously unrecognized post-crash dynamics following the collapse of a housing bubble. A simple model predicts that speculative developers ensure stable pre-crash relative prices between small and large homes while their post-crash exit allows small-home relative values to fall. Evidence from Phoenix supports the model. Although home prices doubled 2004-2006, relative prices of small-to-large homes remained nearly constant but then plummeted post-crash. As s...

  16. Gasoline Prices and Their Relationship to Drunk-Driving Crashes

    OpenAIRE

    Guangqing Chi; Xuan Zhou; Timothy McClure; Paul Gilbert; Arthur Cosby; Li Zhang; Angela Robertson; David Levinson

    2010-01-01

    This study investigates the relationship between changing gasoline prices and drunk-driving crashes. Specifically, we examine the effects of gasoline prices on drunk-driving crashes in Mississippi by age, gender, and race from 2004Ð2008, a period experiencing great fluctuation in gasoline prices. An exploratory visualization by graphs shows that higher gasoline prices are generally associated with fewer drunk-driving crashes. Higher gasoline prices depress drunk- driving crashes among younger...

  17. Conscientious personality and young drivers’ crash risk

    Science.gov (United States)

    Ehsani, Johnathon P.; Li, Kaigang; Simons-Morton, Bruce; Tree-McGrath, Cheyenne Fox; Perlus, Jessamyn; O’Brien, Fearghal; Klauer, Sheila G.

    2015-01-01

    Introduction Personality characteristics are associated with many risk behaviors. However, the relationship between personality traits, risky driving behavior, and crash risk is poorly understood. The purpose of this study was to examine the association between personality, risky driving behavior and crashes and near-crashes, using naturalistic driving research methods. Method Participants’ driving exposure, kinematic risky driving (KRD), high-risk secondary task engagement, and the frequency of crashes and near-crashes (CNC) were assessed over the first 18 months of licensure using naturalistic driving methods. A personality survey (NEO-Five Factor Inventory) was administered at baseline. The association between personality characteristics, KRD rate, secondary task engagement rate and CNC rate was estimated using a linear regression model. Mediation analysis was conducted to examine if participants’ KRD rate or secondary task engagement rate mediated the relationship between personality and CNC. Data were collected as part of the Naturalistic Teen Driving Study. Results Conscientiousness was marginally negatively associated with CNC (path c = −0.034, p = .09) and both potential mediators KRD (path a = −0.040, p = .09) and secondary task engagement while driving (path a = −0.053, p = .03). KRD, but not secondary task engagement, was found to mediate (path b = 0.376, p = .02) the relationship between conscientiousness and CNC (path c’ = −0.025, p = .20). Conclusions Using objective measures of driving behavior and a widely used personality construct, these findings present a causal pathway through which personality and risky driving are associated with CNC. Specifically, more conscientious teenage drivers engaged in fewer risky driving maneuvers, suffered fewer CNC. Practical Applications Part of the variability in crash-risk observed among newly licensed teenage drivers can be explained by personality. Parents and driving instructors may take teenage

  18. Conscientious personality and young drivers' crash risk.

    Science.gov (United States)

    Ehsani, Johnathon P; Li, Kaigang; Simons-Morton, Bruce G; Fox Tree-McGrath, Cheyenne; Perlus, Jessamyn G; O'Brien, Fearghal; Klauer, Sheila G

    2015-09-01

    Personality characteristics are associated with many risk behaviors. However, the relationship between personality traits, risky driving behavior, and crash risk is poorly understood. The purpose of this study was to examine the association between personality, risky driving behavior, and crashes and near-crashes, using naturalistic driving research methods. Participants' driving exposure, kinematic risky driving (KRD), high-risk secondary task engagement, and the frequency of crashes and near-crashes (CNC) were assessed over the first 18months of licensure using naturalistic driving methods. A personality survey (NEO-Five Factor Inventory) was administered at baseline. The association between personality characteristics, KRD rate, secondary task engagement rate, and CNC rate was estimated using a linear regression model. Mediation analysis was conducted to examine if participants' KRD rate or secondary task engagement rate mediated the relationship between personality and CNC. Data were collected as part of the Naturalistic Teen Driving Study. Conscientiousness was marginally negatively associated with CNC (path c=-0.034, p=.09) and both potential mediators KRD (path a=-0.040, p=.09) and secondary task engagement while driving (path a=-0.053, p=.03). KRD, but not secondary task engagement, was found to mediate (path b=0.376, p=.02) the relationship between conscientiousness and CNC (path c'=-0.025, p=.20). Using objective measures of driving behavior and a widely used personality construct, these findings present a causal pathway through which personality and risky driving are associated with CNC. Specifically, more conscientious teenage drivers engaged in fewer risky driving maneuvers, and suffered fewer CNC. Part of the variability in crash risk observed among newly licensed teenage drivers can be explained by personality. Parents and driving instructors may take teenage drivers' personality into account when providing guidance, and establishing norms and

  19. The combined benefits of motorcycle antilock braking systems (ABS) in preventing crashes and reducing crash severity.

    Science.gov (United States)

    Rizzi, Matteo; Kullgren, Anders; Tingvall, Claes

    2016-01-01

    Several studies have reported the benefits of motorcycle antilock braking systems (ABS) in reducing injury crashes, due to improved stability and braking performance. Both aspects may prevent crashes but may also reduce the crash severity when a collision occurs. However, it is still unknown to what extent the reductions in injury crashes with ABS may be due to a combination of these mechanisms. Swedish hospital and police reports (2003-2012) were used. The risk for permanent medical impairment (RPMI) was calculated, showing the risk of at least 1 or 10% permanent medical impairment. In total, 165 crashes involving ABS-equipped motorcycles were compared with 500 crashes with similar motorcycles without ABS. The analysis was performed in 3 steps. First, the reduction in emergency care visits with ABS was calculated using an induced exposure approach. Secondly, the injury mitigating effects of ABS were investigated. The mean RPMI 1+ and RPMI 10+ were analyzed for different crash types. The distributions of impairing injuries (PMI 1+) and severely impairing injuries (PMI 10+) were also analyzed. In the third step, the total reduction of PMI 1+ and PMI 10+ injured motorcyclists was calculated by combining the reductions found in the previous steps. An additional analysis of combined braking systems (CBS) together with ABS was also performed. The results showed that emergency care visits were reduced by 47% with ABS. In the second step, it was found that the mean RPMI 1+ and RPMI 10+ with ABS were 15 and 37% lower, respectively. Finally, the third step showed that the total reductions in terms of crash avoidance and mitigation of PMI 1+ and PMI 10+ injured motorcyclists with ABS were 67 and 55%, respectively. However, PMI 1+ and PMI 10+ leg injuries were not reduced by ABS to the same extent. Indications were found suggesting that the benefits of ABS together with CBS may be greater than ABS alone. This article indicated that motorcycle ABS reduced impairing injuries

  20. Pre-crash system validation with PRESCAN and VEHIL

    NARCIS (Netherlands)

    Gietelink, O.J.; Verburg, D.J.; Labibes, K.; Oostendorp, A.F.

    2004-01-01

    This paper presents the tools for design and validation of Pre-Crash Systems: the software tool PRE-crash SCenario ANalyzer (PRESCAN) and the VEhicle-Hardware-In-the-Loop (VEHIL) facility. PRESCAN allows to investigate a pre-crash scenario in simulation. This scenario can then be compared with tests

  1. Analysis of traffic crash data in Kentucky : 2004-2008.

    Science.gov (United States)

    2009-09-01

    The report documents an analysis of traffic crash data in Kentucky for the years of 2004 through 2008. A primary objective of this study was to determine average crash statistics for Kentucky highways. Average and critical numbers and rates of crashe...

  2. Quasi-ADS-B Based UAV Conflict Detection and Resolution to Manned Aircraft

    Directory of Open Access Journals (Sweden)

    Chin E. Lin

    2015-01-01

    Full Text Available A Conflict Detection and Resolution (CD&R system for manned/unmanned aerial vehicle (UAV based on Automatic Dependent Surveillance-Broadcast (ADS-B concept is designed and verified in this paper. The 900 MHz XBee-Pro is selected as data transponder to broadcast flight information among participating aircraft in omnirange. Standard Compact Position Report (CPR format packet data are automatically broadcasted by ID sequencing under Quasi-ADS-B mechanism. Time Division Multiple Access (TDMA monitoring checks the designated time slot and reallocates the conflict ID. This mechanism allows the transponder to effectively share data with multiple aircraft in near airspace. The STM32f103 microprocessor is designed to handle RF, GPS, and flight data with Windows application on manned aircraft and ground control station simultaneously. Different conflict detection and collision avoidance algorithms can be implemented into the system to ensure flight safety. The proposed UAV/CD&R using Quasi-ADS-B transceiver is tested using ultralight aircraft flying at 100–120 km/hr speed in small airspace for mission simulation. The proposed hardware is also useful to additional applications to mountain hikers for emergency search and rescue. The fundamental function by the proposed UAV/CD&R using Quasi-ADS-B is verified with effective signal broadcasting for surveillance and efficient collision alert and avoidance performance to low altitude flights.

  3. Improving aircraft accident forecasting for an integrated plutonium storage facility

    International Nuclear Information System (INIS)

    Rock, J.C.; Kiffe, J.; McNerney, M.T.; Turen, T.A.

    1998-06-01

    Aircraft accidents pose a quantifiable threat to facilities used to store and process surplus weapon-grade plutonium. The Department of Energy (DOE) recently published its first aircraft accident analysis guidelines: Accident Analysis for Aircraft Crash into Hazardous Facilities. This document establishes a hierarchy of procedures for estimating the small annual frequency for aircraft accidents that impact Pantex facilities and the even smaller frequency of hazardous material released to the environment. The standard establishes a screening threshold of 10 -6 impacts per year; if the initial estimate of impact frequency for a facility is below this level, no further analysis is required. The Pantex Site-Wide Environmental Impact Statement (SWEIS) calculates the aircraft impact frequency to be above this screening level. The DOE Standard encourages more detailed analyses in such cases. This report presents three refinements, namely, removing retired small military aircraft from the accident rate database, correcting the conversion factor from military accident rates (accidents per 100,000 hours) to the rates used in the DOE model (accidents per flight phase), and adjusting the conditional probability of impact for general aviation to more accurately reflect pilot training and local conditions. This report documents a halving of the predicted frequency of an aircraft impact at Pantex and points toward further reductions

  4. Aircraft Impact Assessment of APR1400 Reactor Containment Building

    International Nuclear Information System (INIS)

    Moon, Il Hwan; Kim, Do Yeon; Kim, Jae Hee; Kim, Sang Yun

    2011-01-01

    The implementation of a protection to withstand aircraft impact on safety-related structures and systems is basically based on a probabilistic evaluation for each site, if the licensing body doesn't require a deterministic approach. Existing nuclear power plants in Korea were designed based on the probabilistic approach, and the aircraft impact hazard remained less than a probability of 10 -7 . However, a man-made aircraft impact have been considered as a possible external accident for the nuclear power plant. New plant designs that are to be constructed in the U.S. after July 2009 must consider the effect of impact from a large commercial aircraft according to the requirements of 10 CFR 50.150. Especially, Reactor Containment Building (RCB) housing the safety-related equipment and fuels should be protected safely against aircraft crash without perforation and scabbing failure of external wall. APR1400 RCB is constructed as a prestressed concrete containment vessel (PCCV) which is surrounded by the auxiliary building housing additional safety-related equipment and other systems. In this study, the aircraft impact analyses for the RCB are carried out using Riera forcing function and aircraft model. Considered external wall thickness is 4 ft 6 in. for the cylindrical wall and 4 ft for the dome. Actual strengths of concrete and steel are considered as the material properties. For these analyses, the dynamic increment factor and concrete aging effect are considered in accordance with NEI 07-13(2011)

  5. Floor Response Evaluation for Auxiliary Building Subjected to Aircraft Impact Loading

    International Nuclear Information System (INIS)

    Shin, Sang Shup; Hahm, Daegi; Choi, Inkil

    2014-01-01

    These studies have been aimed to verify and ensure the safety of the targeted walls and structures especially in the viewpoint of the deterministic approach. However, a probabilistic safety assessment as well as deterministic approach for the damage of the internal component in the nuclear power plants (NPPs) subjected to aircraft crash is also needed. A probabilistic safety assessment for aircraft crash includes many uncertainties such as impact velocity, mass, impact location, shape, size, material etc. of aircraft. In this paper, an impact location was selected among the various parameters. This paper found the acceleration floor response spectra at specified locations (safety related components) on the target structure that assumed to be impact velocity 150m/s and maximum fuel for the specified aircraft model. In order to obtain the floor response in case of the crash with a various locations, the analyses for the auxiliary building subjected to aircraft impact were performed using Riera force history method and missile-target interaction method. The difference between responses in case of the building floor subjected to impact was occurred. Thus, in order to obtain the more accurate results, missile-target interaction method was used. This paper found the response at the selected point (node point No. 51). In order to probabilistic assessment for the safety related components, the assessment for a various parameters (velocity, mass, materials etc.) as well as impact locations should be needed

  6. Crash risk factors for interstate large trucks in North Carolina.

    Science.gov (United States)

    Teoh, Eric R; Carter, Daniel L; Smith, Sarah; McCartt, Anne T

    2017-09-01

    Provide an updated examination of risk factors for large truck involvements in crashes resulting in injury or death. A matched case-control study was conducted in North Carolina of large trucks operated by interstate carriers. Cases were defined as trucks involved in crashes resulting in fatal or non-fatal injury, and one control truck was matched on the basis of location, weekday, time of day, and truck type. The matched-pair odds ratio provided an estimate of the effect of various driver, vehicle, or carrier factors. Out-of-service (OOS) brake violations tripled the risk of crashing; any OOS vehicle defect increased crash risk by 362%. Higher historical crash rates (fatal, injury, or all crashes) of the carrier were associated with increased risk of crashing. Operating on a short-haul exemption increased crash risk by 383%. Antilock braking systems reduced crash risk by 65%. All of these results were statistically significant at the 95% confidence level. Other safety technologies also showed estimated benefits, although not statistically significant. With the exception of the finding that short-haul exemption is associated with increased crash risk, results largely bolster what is currently known about large truck crash risk and reinforce current enforcement practices. Results also suggest vehicle safety technologies can be important in lowering crash risk. This means that as safety technology continues to penetrate the fleet, whether from voluntary usage or government mandates, reductions in large truck crashes may be achieved. Practical application: Results imply that increased enforcement and use of crash avoidance technologies can improve the large truck crash problem. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

  7. Response of equipment to aircraft impact

    International Nuclear Information System (INIS)

    Wolf, J.P.; Bucher, K.M.; Skrikerud, P.E.

    1977-01-01

    The loading case of an aircraft crashing onto certain safety-relevant buildings of a nuclear-power plant has recently become, in certain countries, as important as that of the safe-shutdown earthquake. Although its probability of occurrence is substantially smaller than that of the SSE, the analysis is justified as an aircraft can also be regarded as representative of other shock loading cases. For the purpose of design it is convenient to distinguish between the response of the actual structure and that of the equipment. The former, which consists of global stress resultants and of local effects such as spalling, scabbing, penetration and perforation of the concrete of the structure, is quite well understood and is not examined in this paper. The latter, caused by propagating shock waves, has, rather surprisingly, received little attention, although, for earthquake excitation, the analysis of equipment is routinely performed. The high accelerations experienced by the equipment are calculated and the corresponding floor-response spectra show that the airplane crash is dominant in the high-frequency range, when compared to the effect of earthquakes. As the aircraft impacts on a small area of the structure only, and the corresponding function of the load versus time exhibits a substantial content of high frequency, the modelling of the structure has to be rather detailed. Several thousand dynamic degrees of freedom in a finite-element idealization result, when analyzing e.g. a typical reactor auxiliary building, the familiar lumped-beam models used successfully for earthquake analysis can obviously not be chosen. (Auth.)

  8. A hot spot analysis of teenage crashes : an assessment of crashes in Houston, Texas.

    Science.gov (United States)

    2014-09-01

    Today, states have enacted laws to ensure that teen drivers are more skilled and drive safely. The result is : fewer accidents. However, in previous research, when teen crashes were mapped, certain streets and areas : appeared to have more accidents ...

  9. Patterns of severe injury in pediatric car crash victims: Crash Injury Research Engineering Network database.

    Science.gov (United States)

    Brown, J Kristine; Jing, Yuezhou; Wang, Stewart; Ehrlich, Peter F

    2006-02-01

    Motor vehicle crashes (MVCs) account for 50% of pediatric trauma. Safety improvements are typically tested with child crash dummies using an in vitro model. The Crash Injury Research Engineering Network (CIREN) provides an in vivo validation process. Previous research suggest that children in lateral crashes or front-seat locations have higher Injury Severity Scale scores and lower Glasgow Coma Scale scores than those in frontal-impact crashes. However, specific injury patterns and crash characteristics have not been characterized. Data were collected from the CIREN multidisciplinary crash reconstruction network (10 pediatric trauma centers). Injuries were examined with regard to crash direction (frontal/lateral), restraint use, seat location, and change in velocity at impact (DeltaV). Injuries were limited to Abbreviated Injury Scale (AIS) scores of 3 or higher and included head, thoracic, abdominal, pelvic, spine, and long bone (orthopedic) injuries. Standard age groupings (0-4, 5-9, 10-14, and 15-18 years) were used. Statistical analyses used Fisher's Exact test and multiple logistic regressions. Four hundred seventeen MVCs with 2500 injuries were analyzed (males = 219, females = 198). Controlling for DeltaV and age, children in lateral-impact crashes (n = 232) were significantly more likely to suffer severe injuries to the head and thorax as compared with children in frontal crashes (n = 185), who were more likely to suffer severe spine and orthopedic injuries. Children in a front-seat (n = 236) vs those in a back-seat (n = 169) position had more injuries to the thoracic (27% vs 17%), abdominal (21% vs 13%), pelvic (11% vs 1%), and orthopedic (28% vs 10%) regions (P < .05 for all). Seat belts were protective for pelvic (5% vs 12% unbelted) and orthopedic (15% vs 40%) injuries (odds ratio = 3, P < .01 for both). A reproducible pattern of injury is noted for children involved in lateral-impact crashes characterized by head and chest injuries. The Injury Severity

  10. Probabilistic risk assessment of aircraft impact on a spent nuclear fuel dry storage

    Energy Technology Data Exchange (ETDEWEB)

    Almomani, Belal, E-mail: balmomani@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Lee, Sanghoon, E-mail: shlee1222@kmu.ac.kr [Department of Mechanical and Automotive Engineering, Keimyung University, Dalgubeol-daero 1095, Dalseo-gu, Daegu (Korea, Republic of); Jang, Dongchan, E-mail: dongchan.jang@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Kang, Hyun Gook, E-mail: kangh6@rpi.edu [Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States)

    2017-01-15

    Highlights: • A new risk assessment frame is proposed for aircraft impact into an interim dry storage. • It uses event tree analysis, response-structural analysis, consequence analysis, and Monte Carlo simulation. • A case study of the proposed procedure is presented to illustrate the methodology’s application. - Abstract: This paper proposes a systematic risk evaluation framework for one of the most significant impact events on an interim dry storage facility, an aircraft crash, by using a probabilistic approach. A realistic case study that includes a specific cask model and selected impact conditions is performed to demonstrate the practical applicability of the proposed framework. An event tree analysis of an occurred aircraft crash that defines a set of impact conditions and storage cask response is constructed. The Monte-Carlo simulation is employed for the probabilistic approach in consideration of sources of uncertainty associated with the impact loads onto the internal storage casks. The parameters for representing uncertainties that are managed probabilistically include the aircraft impact velocity, the compressive strength of the reinforced concrete wall, the missile shape factor, and the facility wall thickness. Failure probabilities of the impacted wall and a single storage cask under direct mechanical impact load caused by the aircraft crash are estimated. A finite element analysis is applied to simulate the postulated direct engine impact load onto the cask body, and a source term analysis for associated releases of radioactive materials as well as an off-site consequence analysis are performed. Finally, conditional risk contribution calculations are represented by an event tree model. Case study results indicate that no severe risk is presented, as the radiological consequences do not exceed regulatory exposure limits to the public. This risk model can be used with any other representative detailed parameters and reference design concepts for

  11. Sleep-related vehicle crashes on low speed roads.

    Science.gov (United States)

    Filtness, A J; Armstrong, K A; Watson, A; Smith, S S

    2017-02-01

    Very little is known about the characteristics of sleep related (SR) crashes occurring on low speed roads compared with current understanding of the role of sleep in crashes occurring on high speed roads e.g. motorways. To address this gap, analyses were undertaken to identify the differences and similarities between (1) SR crashes occurring on roads with low (≤60km/h) and high (≥100km/h) speed limits, and (2) SR crashes and not-SR crashes occurring on roads with low speed limits. Police reports of all crashes occurring on low and high speed roads over a ten year period between 2000 and 2009 were examined for Queensland, Australia. Attending police officers identified all crash attributes, including 'fatigue/fell asleep', which indicates that the police believe the crash to have a causal factor relating to falling asleep, sleepiness due to sleep loss, time of day, or fatigue. Driver or rider involvement in crashes was classified as SR or not-SR. All crash-associated variables were compared using Chi-square tests (Cramer's V=effect size). A series of logistic regression was performed, with driver and crash characteristics as predictors of crash category. A conservative alpha level of 0.001 determined statistical significance. There were 440,855 drivers or riders involved in a crash during this time; 6923 (1.6%) were attributed as SR. SR crashes on low speed roads have similar characteristics to those on high speed roads with young (16-24y) males consistently over represented. SR crashes on low speed roads are noticeably different to not-SR crashes in the same speed zone in that male and young novice drivers are over represented and outcomes are more severe. Of all the SR crashes identified, 41% occurred on low speed roads. SR crashes are not confined to high speed roads. Low speed SR crashes warrant specific investigation because they occur in densely populated areas, exposing a greater number of people to risk and have more severe outcomes than not-SR crashes

  12. Frequency Analysis of Aircraft hazards for License Application

    International Nuclear Information System (INIS)

    K. Ashley

    2006-01-01

    The preclosure safety analysis for the monitored geologic repository at Yucca Mountain must consider the hazard that aircraft may pose to surface structures. Relevant surface structures are located beneath the restricted airspace of the Nevada Test Site (NTS) on the eastern slope of Yucca Mountain, near the North Portal of the Exploratory Studies Facility Tunnel (Figure 1). The North Portal is located several miles from the Nevada Test and Training Range (NTTR), which is used extensively by the U.S. Air Force (USAF) for training and test flights (Figure 1). The NTS airspace, which is controlled by the U.S. Department of Energy (DOE) for NTS activities, is not part of the NTTR. Agreements with the DOE allow USAF aircraft specific use of the airspace above the NTS (Reference 2.1.1 [DIRS 103472], Section 3.1.1 and Appendix A, Section 2.1; and Reference 2.1.2 [DIRS 157987], Sections 1.26 through 1.29). Commercial, military, and general aviation aircraft fly within several miles to the southwest of the repository site in the Beatty Corridor, which is a broad air corridor that runs approximately parallel to U.S. Highway 95 and the Nevada-California border (Figure 2). These aircraft and other aircraft operations are identified and described in ''Identification of Aircraft Hazards'' (Reference 2.1.3, Sections 6 and 8). The purpose of this analysis is to estimate crash frequencies for aircraft hazards identified for detailed analysis in ''Identification of Aircraft Hazards'' (Reference 2.1.3, Section 8). Reference 2.1.3, Section 8, also identifies a potential hazard associated with electronic jamming, which will be addressed in this analysis. This analysis will address only the repository and not the transportation routes to the site. The analysis is intended to provide the basis for: (1) Categorizing event sequences related to aircraft hazards; (2) Identifying design or operational requirements related to aircraft hazards

  13. Motorcycle crash causes and outcomes : pilot study.

    Science.gov (United States)

    2010-06-01

    The number of motorcyclist crash-related fatalities has more than doubled during the past 10 years. In the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) P.L. 109-59, Congress directed the Secretary ...

  14. Child passengers injured in motor vehicle crashes.

    Science.gov (United States)

    Romano, Eduardo; Kelley-Baker, Tara

    2015-02-01

    During 2010, 171,000 children aged 0-14 were injured in motor vehicle crashes. Despite the severity of the problem, research has been limited, and most of what we know about these children emanates from fatal crash databases. Using information from the General Estimates System, this effort examines the occurrence of non-fatal crashes among children aged 0-14 over the last decade. We found that about 1% of the non-injured children in the file had been driven by a driver who was positive for alcohol. This percentage climbed to about 2% among children who had suffered injuries. Compared with the proportion of alcohol-positive drivers at the time of the crash, the proportion of drivers who sped or failed to obey a traffic signal was significantly higher. The finding that drinking and driving with children did not decrease over time questions the adequacy of the extant child endangerment laws. Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.

  15. Mechanism for rapid sawtooth crashes in tokamaks

    International Nuclear Information System (INIS)

    Aydemir, A.Y.; Hazeltine, R.D.

    1986-09-01

    The sawtooth oscillations in the soft x-ray signals observed in tokamaks are associated with periodic changes in the central electron temperature, T/sub e/. Typically, a slow phase during which the central temperature slowly rises is followed by a fast drop in T/sub e/, associated with flattening of the central temperature. The time scale of the slow phase is determined by various transport processes such as ohmic heating. The resistive internal kink mode was invoked by Kadomtsev to explain the crash phase of the oscillations. Fast crash times observed in the large tokamaks are studied here, especially the fast crashes observed in JET. These sawtooth oscillations are characterized by the absence of any discrenible precursor oscillations, and a rapid collapse of the central temperature in about 100 microseconds. During the crash phase, the hot core region rapidly moves outward and is replaced by colder plasma. Then, this highly asymmetric state relaxes (in ∼100μsec) to a poloidally symmetric state in which a ring of hot plasma surrounds the colder core plasma, producing a hollow pressure profile

  16. Vital Signs-Motor Vehicle Crash Injuries

    Centers for Disease Control (CDC) Podcasts

    2014-10-07

    This podcast is based on the October 2014 CDC Vital Signs report. Motor vehicle crashes are costly and preventable. Learn what can be done to help prevent motor vehicle injuries.  Created: 10/7/2014 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 10/7/2014.

  17. Motor Vehicle Crash Injuries PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    2014-10-07

    This 60 second Public Service Announcement is based on the October 2014 CDC Vital Signs report. Motor vehicle crashes are costly and preventable. Learn what can be done to help prevent motor vehicle injuries.  Created: 10/7/2014 by National Center for Injury Prevention and Control (NCIPC).   Date Released: 10/7/2014.

  18. Improvement of crash compatibility between cars

    NARCIS (Netherlands)

    Huibers, J.A.H.M.; Faerber, E.; Cesari, D.; Hobbs, A.C.; Kampen, B. van; Paez, J.; Wykes, N.J.

    1998-01-01

    This paper will provide an overview of the research work of the European Enhanced Vehicle-safety Committee (EEVC) in the field of crash compatibility between passenger cars. Since July 1997 the EC Commission is partly funding the research work of EEVC. The running period of this project will be two

  19. Motor Vehicle Crash Deaths PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    This 60 second public service announcement is based on the July 2016 CDC Vital Signs report. In the U.S., about 90 people die in motor vehicle crashes each day and thousands more are injured, resulting in hundreds of millions of dollars in direct medical costs each year. Learn what you can do to stay safe.

  20. 2010 traffic crash facts annual report

    Science.gov (United States)

    2010-01-01

    The death rate on Nebraska roadways during 2010 was .97 persons killed per 100 million vehicle miles traveled. This is the lowest death rate recorded since the state first began keeping motor vehicle crash statistics in 1936. The trend of declining d...

  1. Using linked data to evaluate hospital charges for motor vehicle crash victims in Pennsylvania : Crash Outcome Data Evaluation System (CODES) linked data demonstration project

    Science.gov (United States)

    1998-10-01

    The report uses police-reported crash data that have been linked to hospital discharge data to evaluate charges for hospital care provided to motor vehicle crash victims in Pennsylvania. Approximately 17,000 crash victims were hospitalized in Pennsyl...

  2. Assessment of aircraft risk reduction at Pantex Plant

    International Nuclear Information System (INIS)

    Lin, Y.T.; Hedtke, R.; Fike, D.; Diniz, J.

    1996-01-01

    The possibility of an aircraft crashing into the Department of Energy's (DOE) Pantex plant facility has been of concern in risk assessments. In response to public concerns, and in an effort to reduce risks associated with overflights of Pantex, several changes to navigational aids at Amarillo International Airport have been implemented. For over one year, a radar airspace monitor and recording system has been connected to the airport surveillance radar at Amarillo to record the flight paths, aircraft types, and traffic density of aircraft in the vicinity of the Pantex plant. The data has provided a better understanding of the overflight risk at Pantex as well as a means to measure the effectiveness of risk reduction efforts

  3. How similar are two-unit bicycle and motorcycle crashes?

    Science.gov (United States)

    Haworth, Narelle; Debnath, Ashim Kumar

    2013-09-01

    This paper explores the similarities and differences between bicycle and motorcycle crashes with other motor vehicles. If similar treatments can be effective for both bicycle and motorcycle crashes, then greater benefits in terms of crash costs saved may be possible for the same investment in treatments. To reduce the biases associated with under-reporting of these crashes to police, property damage and minor injury crashes were excluded. The most common crash type for both bicycles (31.1%) and motorcycles (24.5%) was intersection from adjacent approaches. Drivers of other vehicles were coded most at fault in the majority of two-unit bicycle (57.0%) and motorcycle crashes (62.7%). The crash types, patterns of fault and factors affecting fault were generally similar for bicycle and motorcycle crashes. This confirms the need to combat the factors contributing to failure of other drivers to yield right of way to two-wheelers, and suggest that some of these actions should prove beneficial to the safety of both motorized and non-motorized two-wheelers. In contrast, child bicyclists were more often at fault, particularly in crashes involving a vehicle leaving the driveway or footpath. The greater reporting of violations by riders and drivers in motorcycle crashes also deserves further investigation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Direct medical costs of motorcycle crashes in Ontario.

    Science.gov (United States)

    Pincus, Daniel; Wasserstein, David; Nathens, Avery B; Bai, Yu Qing; Redelmeier, Donald A; Wodchis, Walter P

    2017-11-20

    There is no reliable estimate of costs incurred by motorcycle crashes. Our objective was to calculate the direct costs of all publicly funded medical care provided to individuals after motorcycle crashes compared with automobile crashes. We conducted a population-based, matched cohort study of adults in Ontario who presented to hospital because of a motorcycle or automobile crash from 2007 through 2013. For each case, we identified 1 control absent a motor vehicle crash during the study period. Direct costs for each case and control were estimated in 2013 Canadian dollars from the payer perspective using methodology that links health care use to individuals over time. We calculated costs attributable to motorcycle and automobile crashes within 2 years using a difference-in-differences approach. We identified 26 831 patients injured in motorcycle crashes and 281 826 injured in automobile crashes. Mean costs attributable to motorcycle and automobile crashes were $5825 and $2995, respectively ( p motorcycle crashes compared with automobile crashes (2194 injured annually/100 000 registered motorcycles v. 718 injured annually/100 000 registered automobiles; incidence rate ratio [IRR] 3.1, 95% confidence interval [CI] 2.8 to 3.3, p motorcycles v. 12 severe injuries annually/100 000 registered automobiles; IRR 10.4, 95% CI 8.3 to 13.1, p motorcycle in Ontario costs the public health care system 6 times the amount of each registered automobile. Medical costs may provide an additional incentive to improve motorcycle safety. © 2017 Joule Inc. or its licensors.

  5. Fatal crashes involving large numbers of vehicles and weather.

    Science.gov (United States)

    Wang, Ying; Liang, Liming; Evans, Leonard

    2017-12-01

    Adverse weather has been recognized as a significant threat to traffic safety. However, relationships between fatal crashes involving large numbers of vehicles and weather are rarely studied according to the low occurrence of crashes involving large numbers of vehicles. By using all 1,513,792 fatal crashes in the Fatality Analysis Reporting System (FARS) data, 1975-2014, we successfully described these relationships. We found: (a) fatal crashes involving more than 35 vehicles are most likely to occur in snow or fog; (b) fatal crashes in rain are three times as likely to involve 10 or more vehicles as fatal crashes in good weather; (c) fatal crashes in snow [or fog] are 24 times [35 times] as likely to involve 10 or more vehicles as fatal crashes in good weather. If the example had used 20 vehicles, the risk ratios would be 6 for rain, 158 for snow, and 171 for fog. To reduce the risk of involvement in fatal crashes with large numbers of vehicles, drivers should slow down more than they currently do under adverse weather conditions. Driver deaths per fatal crash increase slowly with increasing numbers of involved vehicles when it is snowing or raining, but more steeply when clear or foggy. We conclude that in order to reduce risk of involvement in crashes involving large numbers of vehicles, drivers must reduce speed in fog, and in snow or rain, reduce speed by even more than they already do. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

  6. Under-reporting of road traffic crash data in Ghana.

    Science.gov (United States)

    Salifu, Mohammed; Ackaah, Williams

    2012-01-01

    Having reliable estimates of the shortfalls in road traffic crash data is an important prerequisite for setting more realistic targets for crash/casualty reduction programmes and for a better appreciation of the socio-economic significance of road traffic crashes. This study was carried out to establish realistic estimates of the overall shortfall (under-reporting) in the official crash statistics in Ghana over an eight-year period (1997-2004). Surveys were conducted at hospitals and among drivers to generate relevant alternative data which were then matched against records in police crash data files and the official database. Overall shortfalls came from two sources, namely, 'non-reporting' and 'under-recording'. The results show that the level of non-reporting varied significantly with the severity of the crash from about 57% for property damage crashes through 8% for serious injury crashes to 0% for fatal crashes. Crashes involving cyclists and motorcyclists were also substantially non-reported. Under-recording on the other hand declined significantly over the period from an average of 37% in 1997-1998 to 27% in 2003-2004. Thus, the official statistics of road traffic crashes in Ghana are subject to significant shortfalls that need to be accounted for. Correction factors have therefore been suggested for adjusting the official data.

  7. The Pattern of Road Traffic Crashes in South East Iran.

    Science.gov (United States)

    Rad, Mahdieh; Martiniuk, Alexandra Lc; Ansari-Moghaddam, Alireza; Mohammadi, Mahdi; Rashedi, Fariborz; Ghasemi, Ardavan

    2016-09-01

    In the present study, the epidemiologic aspects of road traffic crashes in South East of Iran are described. This cross-sectional study included the profile of 2398 motor vehicle crashes recorded in the police office in one Year in South East of Iran. Data collected included: demographics, the type of crash, type of involved vehicle, location of crash and factors contributing to the crash. Descriptive statistics were used for data analysis. Collisions with other vehicles or objects contributed the highest proportion (62.4%) of motor vehicle crashes. Human factors including careless driving, violating traffic laws, speeding, and sleep deprivation/fatigue were the most important causal factors accounting for 90% of road crashes. Data shows that 41% of drivers were not using a seat belt at the time of crash. One- third of the crashes resulted in injury (25%) or death (5%). Reckless driving such as speeding and violation of traffic laws are major risk factors for crashes in the South East of Iran. This highlights the need for education along with traffic law enforcement to reduce motor vehicle crashes in future.

  8. Analysis of the crash of TK 1951 using CATS

    Energy Technology Data Exchange (ETDEWEB)

    Ale, B.J.M., E-mail: b.j.m.ale@tudelft.n [Risk Centre, TU-Delft, Delft (Netherlands); Bellamy, L.J. [White Queen BV, Hoofddorp (Netherlands); Cooper, J. [JPSC Consultants, Surrey (United Kingdom); Ababei, D.; Kurowicka, D.; Morales, O. [TU-Delft, Delft (Netherlands); Spouge, J. [DNV, London (United Kingdom)

    2010-05-15

    On February 25, 2009, flight TK 1951, a Boeing 737-800 operated by Turkish Airlines, crashed approximately 1.5 km before the intended runway at Amsterdam Schiphol Airport. On board were 135 people-128 passengers and 7 crew. Of these 9 were killed and 86 were injured. The aircraft was destroyed. The official inquiry into the cause of the accident is being conducted by the Dutch Safety Board (Onderzoeksraad Voor Veiligheid, OvV). Prior to the accident the Netherlands Ministry of Transport, Public Works and Water Management had already embarked on a project to model the accident genesis of air transport accidents with the aim of quantifying the risks of air traffic and supporting the development of further measures and methods to reduce these risks. In this paper information regarding the accident is confronted with an analysis using the Causal model for Air Transport Safety (CATS). This enables drawing of some more theoretical conclusions about the accident and about the validity of CATS.

  9. Analysis of the crash of TK 1951 using CATS

    International Nuclear Information System (INIS)

    Ale, B.J.M.; Bellamy, L.J.; Cooper, J.; Ababei, D.; Kurowicka, D.; Morales, O.; Spouge, J.

    2010-01-01

    On February 25, 2009, flight TK 1951, a Boeing 737-800 operated by Turkish Airlines, crashed approximately 1.5 km before the intended runway at Amsterdam Schiphol Airport. On board were 135 people-128 passengers and 7 crew. Of these 9 were killed and 86 were injured. The aircraft was destroyed. The official inquiry into the cause of the accident is being conducted by the Dutch Safety Board (Onderzoeksraad Voor Veiligheid, OvV). Prior to the accident the Netherlands Ministry of Transport, Public Works and Water Management had already embarked on a project to model the accident genesis of air transport accidents with the aim of quantifying the risks of air traffic and supporting the development of further measures and methods to reduce these risks. In this paper information regarding the accident is confronted with an analysis using the Causal model for Air Transport Safety (CATS). This enables drawing of some more theoretical conclusions about the accident and about the validity of CATS.

  10. Survivors’ experiences from a train crash

    Directory of Open Access Journals (Sweden)

    Rebecca Forsberg

    2011-11-01

    Full Text Available Rarely described are people's lived experiences from severe injury events such as train crashes. The number of train crashes named disasters with ≥10 killed and/or ≥100 nonfatally injured grows globally and the trend shows that more people survive these disasters today than did so in the past. This results in an increased number of survivors needing care. The aim of the study was to explore survivors’ experiences from a train crash. Narrative interviews were performed with 14 passengers 4 years after a train crash event. Qualitative content analysis was used to analyse the interviews. Experiences were captured in three main themes: (1 Living in the mode of existential threat describes how the survivors first lost control, then were thrown into a state of unimaginable chaos as they faced death. (2 Dealing with the unthinkable described how survivors restored control, the central role of others, and the importance of reconstructing the event to move forward in their processing. (3 Having cheated death shows how some became shackled by their history, whereas others overcame the haunting of unforgettable memories. Furthermore, the result shows how all experienced a second chance in life. Experiencing a train crash meant that the passengers experienced severe vulnerability and a threat to life and interdependence turned out to play a crucial role. Focusing on helping other passengers on site was one way to regain the loss of control and kept the chaos at bay. Family, friends, and fellow passengers turned out to be extremely important during the recovery process why such closeness should be promoted and facilitated.

  11. Propulsion controlled aircraft computer

    Science.gov (United States)

    Cogan, Bruce R. (Inventor)

    2010-01-01

    A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.

  12. Ultralight Cut-Paper-Based Self-Charging Power Unit for Self-Powered Portable Electronic and Medical Systems.

    Science.gov (United States)

    Guo, Hengyu; Yeh, Min-Hsin; Zi, Yunlong; Wen, Zhen; Chen, Jie; Liu, Guanlin; Hu, Chenguo; Wang, Zhong Lin

    2017-05-23

    The development of lightweight, superportable, and sustainable power sources has become an urgent need for most modern personal electronics. Here, we report a cut-paper-based self-charging power unit (PC-SCPU) that is capable of simultaneously harvesting and storing energy from body movement by combining a paper-based triboelectric nanogenerator (TENG) and a supercapacitor (SC), respectively. Utilizing the paper as the substrate with an assembled cut-paper architecture, an ultralight rhombic-shaped TENG is achieved with highly specific mass/volume charge output (82 nC g -1 /75 nC cm -3 ) compared with the traditional acrylic-based TENG (5.7 nC g -1 /5.8 nC cm -3 ), which can effectively charge the SC (∼1 mF) to ∼1 V in minutes. This wallet-contained PC-SCPU is then demonstrated as a sustainable power source for driving wearable and portable electronic devices such as a wireless remote control, electric watch, or temperature sensor. This study presents a potential paper-based portable SCPU for practical and medical applications.

  13. Rotation curves of high-resolution LSB and SPARC galaxies with fuzzy and multistate (ultralight boson) scalar field dark matter

    Science.gov (United States)

    Bernal, T.; Fernández-Hernández, L. M.; Matos, T.; Rodríguez-Meza, M. A.

    2018-04-01

    Cold dark matter (CDM) has shown to be an excellent candidate for the dark matter (DM) of the Universe at large scales; however, it presents some challenges at the galactic level. The scalar field dark matter (SFDM), also called fuzzy, wave, Bose-Einstein condensate, or ultralight axion DM, is identical to CDM at cosmological scales but different at the galactic ones. SFDM forms core haloes, it has a natural cut-off in its matter power spectrum, and it predicts well-formed galaxies at high redshifts. In this work we reproduce the rotation curves of high-resolution low surface brightness (LSB) and SPARC galaxies with two SFDM profiles: (1) the soliton+NFW profile in the fuzzy DM (FDM) model, arising empirically from cosmological simulations of real, non-interacting scalar field (SF) at zero temperature, and (2) the multistate SFDM (mSFDM) profile, an exact solution to the Einstein-Klein-Gordon equations for a real, self-interacting SF, with finite temperature into the SF potential, introducing several quantum states as a realistic model for an SFDM halo. From the fits with the soliton+NFW profile, we obtained for the boson mass 0.212 motivated framework additional or alternative to the FDM profile.

  14. Ultra-light and flexible pencil-trace anode for high performance potassium-ion and lithium-ion batteries

    Directory of Open Access Journals (Sweden)

    Zhixin Tai

    2017-07-01

    Full Text Available Engineering design of battery configurations and new battery system development are alternative approaches to achieve high performance batteries. A novel flexible and ultra-light graphite anode is fabricated by simple friction drawing on filter paper with a commercial 8B pencil. Compared with the traditional anode using copper foil as current collector, this innovative current-collector-free design presents capacity improvement of over 200% by reducing the inert weight of the electrode. The as-prepared pencil-trace electrode exhibits excellent rate performance in potassium-ion batteries (KIBs, significantly better than in lithium-ion batteries (LIBs, with capacity retention of 66% for the KIB vs. 28% for the LIB from 0.1 to 0.5 A g−1. It also shows a high reversible capacity of ∼230 mAh g−1 at 0.2 A g−1, 75% capacity retention over 350 cycles at 0.4 A g−1and the highest rate performance (based on the total electrode weight among graphite electrodes for K+ storage reported so far. Keywords: Current-collector-free, Flexible pencil-trace electrode, Potassium-ion battery, Lithium-ion battery, Layer-by-layer interconnected architecture

  15. Neighborhood Influences on Vehicle-Pedestrian Crash Severity.

    Science.gov (United States)

    Toran Pour, Alireza; Moridpour, Sara; Tay, Richard; Rajabifard, Abbas

    2017-12-01

    Socioeconomic factors are known to be contributing factors for vehicle-pedestrian crashes. Although several studies have examined the socioeconomic factors related to the location of the crashes, limited studies have considered the socioeconomic factors of the neighborhood where the road users live in vehicle-pedestrian crash modelling. This research aims to identify the socioeconomic factors related to both the neighborhoods where the road users live and where crashes occur that have an influence on vehicle-pedestrian crash severity. Data on vehicle-pedestrian crashes that occurred at mid-blocks in Melbourne, Australia, was analyzed. Neighborhood factors associated with road users' residents and location of crash were investigated using boosted regression tree (BRT). Furthermore, partial dependence plots were applied to illustrate the interactions between these factors. We found that socioeconomic factors accounted for 60% of the 20 top contributing factors to vehicle-pedestrian crashes. This research reveals that socioeconomic factors of the neighborhoods where the road users live and where the crashes occur are important in determining the severity of the crashes, with the former having a greater influence. Hence, road safety countermeasures, especially those focussing on the road users, should be targeted at these high-risk neighborhoods.

  16. Crash probability estimation via quantifying driver hazard perception.

    Science.gov (United States)

    Li, Yang; Zheng, Yang; Wang, Jianqiang; Kodaka, Kenji; Li, Keqiang

    2018-07-01

    Crash probability estimation is an important method to predict the potential reduction of crash probability contributed by forward collision avoidance technologies (FCATs). In this study, we propose a practical approach to estimate crash probability, which combines a field operational test and numerical simulations of a typical rear-end crash model. To consider driver hazard perception characteristics, we define a novel hazard perception measure, called as driver risk response time, by considering both time-to-collision (TTC) and driver braking response to impending collision risk in a near-crash scenario. Also, we establish a driving database under mixed Chinese traffic conditions based on a CMBS (Collision Mitigation Braking Systems)-equipped vehicle. Applying the crash probability estimation in this database, we estimate the potential decrease in crash probability owing to use of CMBS. A comparison of the results with CMBS on and off shows a 13.7% reduction of crash probability in a typical rear-end near-crash scenario with a one-second delay of driver's braking response. These results indicate that CMBS is positive in collision prevention, especially in the case of inattentive drivers or ole drivers. The proposed crash probability estimation offers a practical way for evaluating the safety benefits in the design and testing of FCATs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Repeatability study of replicate crash tests: A signal analysis approach.

    Science.gov (United States)

    Seppi, Jeremy; Toczyski, Jacek; Crandall, Jeff R; Kerrigan, Jason

    2017-10-03

    To provide an objective basis on which to evaluate the repeatability of vehicle crash test methods, a recently developed signal analysis method was used to evaluate correlation of sensor time history data between replicate vehicle crash tests. The goal of this study was to evaluate the repeatability of rollover crash tests performed with the Dynamic Rollover Test System (DRoTS) relative to other vehicle crash test methods. Test data from DRoTS tests, deceleration rollover sled (DRS) tests, frontal crash tests, frontal offset crash tests, small overlap crash tests, small overlap impact (SOI) crash tests, and oblique crash tests were obtained from the literature and publicly available databases (the NHTSA vehicle database and the Insurance Institute for Highway Safety TechData) to examine crash test repeatability. Signal analysis of the DRoTS tests showed that force and deformation time histories had good to excellent repeatability, whereas vehicle kinematics showed only fair repeatability due to the vehicle mounting method for one pair of tests and slightly dissimilar mass properties (2.2%) in a second pair of tests. Relative to the DRS, the DRoTS tests showed very similar or higher levels of repeatability in nearly all vehicle kinematic data signals with the exception of global X' (road direction of travel) velocity and displacement due to the functionality of the DRoTS fixture. Based on the average overall scoring metric of the dominant acceleration, DRoTS was found to be as repeatable as all other crash tests analyzed. Vertical force measures showed good repeatability and were on par with frontal crash barrier forces. Dynamic deformation measures showed good to excellent repeatability as opposed to poor repeatability seen in SOI and oblique deformation measures. Using the signal analysis method as outlined in this article, the DRoTS was shown to have the same or better repeatability of crash test methods used in government regulatory and consumer evaluation test

  18. A Study on External Fire Damage of Structures subjected to Aircraft Impact

    International Nuclear Information System (INIS)

    Shin, Sang Shup; Hahm, Daegi; Kim, Min Kyu

    2015-01-01

    A large commercial aircraft consists of various components as fuselage, wings, fuel tank, engine etc. During a collision of the aircraft, the fuel tank with a large amount of jet fuel have a significant effect on the total load of the aircraft as well as causing explosive fire and smoke which affect the safety of the structure and equipment. US Sandia National Laboratories and Finland VTT etc. performed the test and simulation studies to evaluate the dispersion range of the fluid after the crash of liquid filled cylinder missiles. The test condition and results have been referred in this paper. The fluid modeling approach using SPH is applied to evaluate the dispersing range of the fluid, and is compared with the Brown's results. The jet fuel is idealized as particles contained in an aluminum cylinder missile, where those particles can be dispersed to the surrounding area after the missile crashes into a rigid target. The fluid model using the SPH method is briefly verified through comparison with test results, and then the modelling method is applied to a jet fuel model in an aircraft model. The dispersion analysis of jet fuel caused by aircraft impact is performed using an aircraft model for the determination of fire duration and fire affected zone in a nuclear power plant. Finally, the structural integrity of the roof of the structure during a jet fuel fire is evaluated. In this study, the filled jet fuel was modeled by using smooth particle hydrodynamics technique; jet fuel spread area following an aircraft crash was analyzed

  19. A Study on External Fire Damage of Structures subjected to Aircraft Impact

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Sang Shup [Hanyang University, Seoul (Korea, Republic of); Hahm, Daegi; Kim, Min Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    A large commercial aircraft consists of various components as fuselage, wings, fuel tank, engine etc. During a collision of the aircraft, the fuel tank with a large amount of jet fuel have a significant effect on the total load of the aircraft as well as causing explosive fire and smoke which affect the safety of the structure and equipment. US Sandia National Laboratories and Finland VTT etc. performed the test and simulation studies to evaluate the dispersion range of the fluid after the crash of liquid filled cylinder missiles. The test condition and results have been referred in this paper. The fluid modeling approach using SPH is applied to evaluate the dispersing range of the fluid, and is compared with the Brown's results. The jet fuel is idealized as particles contained in an aluminum cylinder missile, where those particles can be dispersed to the surrounding area after the missile crashes into a rigid target. The fluid model using the SPH method is briefly verified through comparison with test results, and then the modelling method is applied to a jet fuel model in an aircraft model. The dispersion analysis of jet fuel caused by aircraft impact is performed using an aircraft model for the determination of fire duration and fire affected zone in a nuclear power plant. Finally, the structural integrity of the roof of the structure during a jet fuel fire is evaluated. In this study, the filled jet fuel was modeled by using smooth particle hydrodynamics technique; jet fuel spread area following an aircraft crash was analyzed.

  20. Camera systems for crash and hyge testing

    Science.gov (United States)

    Schreppers, Frederik

    1995-05-01

    Since the beginning of the use of high speed cameras for crash and hyge- testing substantial changements have taken place. Both the high speed cameras and the electronic control equipment are more sophisticated nowadays. With regard to high speed equipment, a short historical retrospective view will show that concerning high speed cameras, the improvements are mainly concentrated in design details, where as the electronic control equipment has taken full advantage of the rapid progress in electronic and computer technology in the course of the last decades. Nowadays many companies and institutes involved in crash and hyge-testing wish to perform this testing, as far as possible, as an automatic computer controlled routine in order to maintain and improve security and quality. By means of several in practice realize solutions, it will be shown how their requirements could be met.

  1. Motor Vehicle Crash Deaths PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    2016-07-06

    This 60 second public service announcement is based on the July 2016 CDC Vital Signs report. In the U.S., about 90 people die in motor vehicle crashes each day and thousands more are injured, resulting in hundreds of millions of dollars in direct medical costs each year. Learn what you can do to stay safe.  Created: 7/6/2016 by National Center for Injury Prevention and Control (NCIPC).   Date Released: 7/6/2016.

  2. Analysis of aircraft impact to concrete structures

    International Nuclear Information System (INIS)

    Arros, Jorma; Doumbalski, Nikolay

    2007-01-01

    Analysis of aircraft impact to nuclear power plant structures is discussed utilizing a simplified model of a 'fictitious nuclear building' to perform analyses using LS-DYNA software, representing the loading: (i) by the Riera force history method and (ii) by modeling the crash by impacting a model of a plane similar to Boeing 747-400 to the structure (i.e., 'missile-target interaction method'). Points discussed include: (1) comparison of shock loading within the building as obtained from the Riera force history analysis versus from the missile-target interaction analysis, (2) sensitivity of the results on the assumed Riera force loading area, (3) linear versus nonlinear modeling and (4) on failure criteria

  3. Life-threatening motor vehicle crashes in bright sunlight

    OpenAIRE

    Redelmeier, Donald A.; Raza, Sheharyar

    2017-01-01

    Abstract Bright sunlight may create visual illusions that lead to driver error, including fallible distance judgment from aerial perspective. We tested whether the risk of a life-threatening motor vehicle crash was increased when driving in bright sunlight. This longitudinal, case-only, paired-comparison analysis evaluated patients hospitalized because of a motor vehicle crash between January 1, 1995 and December 31, 2014. The relative risk of a crash associated with bright sunlight was estim...

  4. Conceptual design of hybrid-electric transport aircraft

    Science.gov (United States)

    Pornet, C.; Isikveren, A. T.

    2015-11-01

    The European Flightpath 2050 and corresponding Strategic Research and Innovation Agenda (SRIA) as well as the NASA Environmentally Responsible Aviation N+ series have elaborated aggressive emissions and external noise reduction targets according to chronological waypoints. In order to deliver ultra-low or even zero in-flight emissions levels, there exists an increasing amount of international research and development emphasis on electrification of the propulsion and power systems of aircraft. Since the late 1990s, a series of experimental and a host of burgeouning commercial activities for fixed-wing aviation have focused on glider, ultra-light and light-sport airplane, and this is proving to serve as a cornerstone for more ambitious transport aircraft design and integration technical approaches. The introduction of hybrid-electric technology has dramatically expanded the design space and the full-potential of these technologies will be drawn through synergetic, tightly-coupled morphological and systems integration emphasizing propulsion - as exemplified by the potential afforded by distributed propulsion solutions. With the aim of expanding upon the current repository of knowledge associated with hybrid-electric propulsion systems a quad-fan arranged narrow-body transport aircraft equipped with two advanced Geared-Turbofans (GTF) and two Electrical Fans (EF) in an under-wing podded installation is presented in this technical article. The assessment and implications of an increasing Degree-of-Hybridization for Useful Power (HP,USE) on the overall sizing, performance as well as flight technique optimization of fuel-battery hybrid-electric aircraft is addressed herein. The integrated performance of the concept was analyzed in terms of potential block fuel burn reduction and change in vehicular efficiency in comparison to a suitably projected conventional aircraft employing GTF-only propulsion targeting year 2035. Results showed that by increasing HP,USE, significant

  5. Crash data and rates for age-sex groups of drivers, 1996

    Science.gov (United States)

    1998-01-01

    The results of this research note are based on 1996data for fatal crashes, driver licenses, and estimates of total crashes based upon data obtained from the nationally representative sample of crashes gathered in the General Estimates System (GES). T...

  6. Association knowledge for fatal run-off-road crashes by Multiple Correspondence Analysis

    Directory of Open Access Journals (Sweden)

    Subasish Das

    2016-03-01

    Results of the MCA method can help researchers select the most effective crash countermeasures. Further work on the degree of association between the identified crash contributing factors can help safety management systems develop the most efficient crash reduction strategies.

  7. An investigation of the speeding-related crash designation through crash narrative reviews sampled via logistic regression.

    Science.gov (United States)

    Fitzpatrick, Cole D; Rakasi, Saritha; Knodler, Michael A

    2017-01-01

    Speed is one of the most important factors in traffic safety as higher speeds are linked to increased crash risk and higher injury severities. Nearly a third of fatal crashes in the United States are designated as "speeding-related", which is defined as either "the driver behavior of exceeding the posted speed limit or driving too fast for conditions." While many studies have utilized the speeding-related designation in safety analyses, no studies have examined the underlying accuracy of this designation. Herein, we investigate the speeding-related crash designation through the development of a series of logistic regression models that were derived from the established speeding-related crash typologies and validated using a blind review, by multiple researchers, of 604 crash narratives. The developed logistic regression model accurately identified crashes which were not originally designated as speeding-related but had crash narratives that suggested speeding as a causative factor. Only 53.4% of crashes designated as speeding-related contained narratives which described speeding as a causative factor. Further investigation of these crashes revealed that the driver contributing code (DCC) of "driving too fast for conditions" was being used in three separate situations. Additionally, this DCC was also incorrectly used when "exceeding the posted speed limit" would likely have been a more appropriate designation. Finally, it was determined that the responding officer only utilized one DCC in 82% of crashes not designated as speeding-related but contained a narrative indicating speed as a contributing causal factor. The use of logistic regression models based upon speeding-related crash typologies offers a promising method by which all possible speeding-related crashes could be identified. Published by Elsevier Ltd.

  8. Small transport aircraft technology

    Science.gov (United States)

    Williams, L. J.

    1983-01-01

    Information on commuter airline trends and aircraft developments is provided to upgrade the preliminary findings of a NASA-formed small transport aircraft technology (STAT) team, established to determine whether the agency's research and development programs could help commuter aircraft manufacturers solve technical problems related to passenger acceptance and use of 19- to 50-passenger aircraft. The results and conclusions of the full set of completed STAT studies are presented. These studies were performed by five airplane manufacturers, five engine manufacturers, and two propeller manufacturers. Those portions of NASA's overall aeronautics research and development programs which are applicable to commuter aircraft design are summarized. Areas of technology that might beneficially be expanded or initiated to aid the US commuter aircraft manufacturers in the evolution of improved aircraft for the market are suggested.

  9. The advanced role of computational mechanics and visualization in science and technology: analysis of the Germanwings Flight 9525 crash

    International Nuclear Information System (INIS)

    Chen, Goong; Wang, Yi-Ching; Gu, Cong; Perronnet, Alain; Yao, Pengfei; Bin-Mohsin, Bandar; Hajaiej, Hichem; Scully, Marlan O

    2017-01-01

    Computational mathematics, physics and engineering form a major constituent of modern computational science, which now stands on an equal footing with the established branches of theoretical and experimental sciences. Computational mechanics solves problems in science and engineering based upon mathematical modeling and computing, bypassing the need for expensive and time-consuming laboratory setups and experimental measurements. Furthermore, it allows the numerical simulations of large scale systems, such as the formation of galaxies that could not be done in any earth bound laboratories. This article is written as part of the 21st Century Frontiers Series to illustrate some state-of-the-art computational science. We emphasize how to do numerical modeling and visualization in the study of a contemporary event, the pulverizing crash of the Germanwings Flight 9525 on March 24, 2015, as a showcase. Such numerical modeling and the ensuing simulation of aircraft crashes into land or mountain are complex tasks as they involve both theoretical study and supercomputing of a complex physical system. The most tragic type of crash involves ‘pulverization’ such as the one suffered by this Germanwings flight. Here, we show pulverizing airliner crashes by visualization through video animations from supercomputer applications of the numerical modeling tool LS-DYNA. A sound validation process is challenging but essential for any sophisticated calculations. We achieve this by validation against the experimental data from a crash test done in 1993 of an F4 Phantom II fighter jet into a wall. We have developed a method by hybridizing two primary methods: finite element analysis and smoothed particle hydrodynamics . This hybrid method also enhances visualization by showing a ‘debris cloud’. Based on our supercomputer simulations and the visualization, we point out that prior works on this topic based on ‘hollow interior’ modeling can be quite problematic and, thus, not

  10. The advanced role of computational mechanics and visualization in science and technology: analysis of the Germanwings Flight 9525 crash

    Science.gov (United States)

    Chen, Goong; Wang, Yi-Ching; Perronnet, Alain; Gu, Cong; Yao, Pengfei; Bin-Mohsin, Bandar; Hajaiej, Hichem; Scully, Marlan O.

    2017-03-01

    Computational mathematics, physics and engineering form a major constituent of modern computational science, which now stands on an equal footing with the established branches of theoretical and experimental sciences. Computational mechanics solves problems in science and engineering based upon mathematical modeling and computing, bypassing the need for expensive and time-consuming laboratory setups and experimental measurements. Furthermore, it allows the numerical simulations of large scale systems, such as the formation of galaxies that could not be done in any earth bound laboratories. This article is written as part of the 21st Century Frontiers Series to illustrate some state-of-the-art computational science. We emphasize how to do numerical modeling and visualization in the study of a contemporary event, the pulverizing crash of the Germanwings Flight 9525 on March 24, 2015, as a showcase. Such numerical modeling and the ensuing simulation of aircraft crashes into land or mountain are complex tasks as they involve both theoretical study and supercomputing of a complex physical system. The most tragic type of crash involves ‘pulverization’ such as the one suffered by this Germanwings flight. Here, we show pulverizing airliner crashes by visualization through video animations from supercomputer applications of the numerical modeling tool LS-DYNA. A sound validation process is challenging but essential for any sophisticated calculations. We achieve this by validation against the experimental data from a crash test done in 1993 of an F4 Phantom II fighter jet into a wall. We have developed a method by hybridizing two primary methods: finite element analysis and smoothed particle hydrodynamics. This hybrid method also enhances visualization by showing a ‘debris cloud’. Based on our supercomputer simulations and the visualization, we point out that prior works on this topic based on ‘hollow interior’ modeling can be quite problematic and, thus, not

  11. Crash protection of stock car racing drivers--application of biomechanical analysis of Indy car crash research.

    Science.gov (United States)

    Melvin, John W; Begeman, Paul C; Faller, Ronald K; Sicking, Dean L; McClellan, Scott B; Maynard, Edwin; Donegan, Michael W; Mallott, Annette M; Gideon, Thomas W

    2006-11-01

    Biomechanical analysis of Indy car crashes using on-board impact recorders (Melvin et al. 1998, Melvin et al. 2001) indicates that Indy car driver protection in high-energy crashes can be achieved in frontal, side, and rear crashes with severities in the range of 100 to 135 G peak deceleration and velocity changes in the range of 50 to 70 mph. These crashes were predominantly single-car impacts with the rigid concrete walls of oval tracks. This impressive level of protection was found to be due to the unique combination of a very supportive and tight-fitting cockpit-seating package, a six-point belt restraint system, and effective head padding with an extremely strong chassis that defines the seat and cockpit of a modern Indy car. In 2000 and 2001, a series of fatal crashes in stock car racing created great concern for improving the crash protection for drivers in those racecars. Unlike the Indy car, the typical racing stock car features a more spacious driver cockpit due to its resemblance to the shape of a passenger car. The typical racing seat used in stock cars did not have the same configuration or support characteristics of the Indy car seat, and five-point belt restraints were used. The tubular steel space frame chassis of a stock car also differs from an Indy car's composite chassis structure in both form and mechanical behavior. This paper describes the application of results of the biomechanical analysis of the Indy car crash studies to the unique requirements of stock car racing driver crash protection. Sled test and full-scale crash test data using both Hybrid III frontal crash anthropomorphic test devices (ATDs) and BioSID side crash ATDs for the purpose of evaluating countermeasures involving restraint systems, seats and head/neck restraints has been instrumental in guiding these developments. In addition, the development of deformable walls for oval tracks (the SAFER Barrier) is described as an adjunct to improved occupant restraint through control

  12. Structural analysis of aircraft impact on a nuclear powered ship

    International Nuclear Information System (INIS)

    Dietrich, R.

    1976-01-01

    As part of a general safety analysis, the reliability against structural damage due to an aircraft crash on a nuclear powered ship is evaluated. This structural analysis is an aid in safety design. It is assumed that a Phantom military jet-fighter hits a nuclear powered ship. The total reaction force due to such an aircraft impact on a rigid barrier is specified in the guidelines of the Reaktor-Sicherheitskommission (German Safety Advisory Committee) for pressurized water reactors. This paper investigates the aircraft impact on the collision barrier at the side of the ship. The aircraft impact on top of the reactor hatchway is investigated by another analysis. It appears that the most unfavorable angle of impact is always normal to the surface of the collision barrier. Consequently, only normal impact will be considered here. For the specific case of an aircraft striking a nuclear powered ship, the following two effects are considered: Local penetration and dynamic response of the structure. (Auth.)

  13. Cell phone use and traffic crash risk: a culpability analysis.

    Science.gov (United States)

    Asbridge, Mark; Brubacher, Jeff R; Chan, Herbert

    2013-02-01

    The use of a cell phone or communication device while driving is illegal in many jurisdictions, yet evidence evaluating the crash risk associated with cell phone use in naturalistic settings is limited. This article aims to determine whether cell phone use while driving increases motor vehicle crash culpability. Method Drivers involved in crashes where police reported cell phone use (n = 312) and propensity matched drivers (age, sex, suspect alcohol/drug impairment, crash type, date, time of day, geographical location) without cell phone use (n = 936) were drawn from Insurance Corporation of British Columbia Traffic Accident System data. A standardized scoring tool, modified to account for Canadian driving conditions, was used to determine crash culpability from police reports on all drivers from the crashes. The association between crash culpability and cell phone use was determined, with additional subgroup analyses based on crash severity, driver characteristics and type of licence. A comparison of crashes with vs without cell phones revealed an odds ratio of 1.70 (95% confidence interval 1.22-2.36; P = 0.002). This association was consistent after adjustment for matching variables and other covariates. Subgroup analyses demonstrated an association for male drivers, unimpaired drivers, injured and non-injured drivers, and for drivers aged between 26 and 65 years. Crash culpability was found to be significantly associated with cell phone use by drivers, increasing the odds of a culpable crash by 70% compared with drivers who did not use a cell phone. This increased risk was particularly high for middle-aged drivers.

  14. Wrong-way driving crashes on French divided roads.

    Science.gov (United States)

    Kemel, Emmanuel

    2015-02-01

    The objective of divided roads is to increase users' safety by posting unidirectional traffic flows. It happens however that drivers proceed in the wrong direction, endangering themselves as well as other users. The crashes caused by wrong-way drivers are generally spotlighted by the media and call for public intervention. This paper proposes a characterization of wrong-way driving crashes occurring on French divided road on the 2008-2012 period. The objective is to identify the factors that delineate between wrong-way driving crashes and other crashes. Building on the national injury road crash database, 266 crashes involving a wrong-way driver were identified. Their characteristics (related to timing, location, vehicle and driver) are compared to those of the 22,120 other crashes that occurred on the same roads over the same period. The comparison relies on descriptive statistics, completed by a logistic regression. Wrong-way driving crashes are rare but severe. They are more likely to occur during night hours and on non-freeway roads than other crashes. Wrong-way drivers are older, more likely to be intoxicated, to be locals, to drive older vehicles, mainly passenger cars without passengers, than other drivers. The differences observed across networks can help prioritizing public intervention. Most of the identified WW-driving factors deal with cognitive impairment. Therefore, the specific countermeasures such as alternative road signs should be designed for and tested on cognitively impaired drivers. Nevertheless, WW-driving factors are also risk factors for other types of crashes (e.g. elderly driving, drunk driving and age of the vehicle). This suggests that, instead of (or in addition to) developing WW-driving specific countermeasures, managing these risk factors would help reducing a larger number of crashes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Aircraft Carrier Exposure Testing of Aircraft Materials

    National Research Council Canada - National Science Library

    Lee, Eui

    2004-01-01

    .... Test and control specimens were affixed on exposure racks and installed on aircraft carriers to compare adhesive bonding primers for aluminum and to determine the static property behavior of various...

  16. Crash simulation: an immersive learning model.

    Science.gov (United States)

    Wenham, John; Bennett, Paul; Gleeson, Wendy

    2017-12-26

    Far West New South Wales Local Emergency Management Committee runs an annual crash simulation exercise to assess the operational readiness of all local emergency services to coordinate and manage a multi-casualty exercise. Since 2009, the Broken Hill University Department of Rural Health (BHUDRH) has collaborated with the committee, enabling the inclusion of health students in this exercise. It is an immersive interprofessional learning experience that evaluates teamwork, communication and safe effective clinical trauma management outside the hospital setting. After 7 years of modifying and developing the exercise, we set out to evaluate its impact on the students' learning, and sought ethics approval from the University of Sydney for this study. At the start of this year's crash simulation, students were given information sheets and consent forms with regards to the research. Once formal debriefing had finished, the researchers conducted a semi-structured focus-group interview with the health students to gain insight into their experience and their perceived value of the training. Students also completed short-answer questionnaires, and the anonymised responses were analysed. Crash simulation … evaluates teamwork, communication and safe effective clinical trauma management IMPLICATIONS: Participants identified that this multidisciplinary learning opportunity in a pre-hospital mass casualty situation was of value to them. It has taken them outside of their usually protected hospital or primary care setting and tested their critical thinking and communication skills. We recommend this learning concept to other educational institutions. Further research will assess the learning value of the simulated event to the other agencies involved. © 2017 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

  17. Sawtooth crashes at high beta on JET

    Energy Technology Data Exchange (ETDEWEB)

    Alper, B; Huysmans, G T.A.; Sips, A C.C. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Nave, M F.F. [Universidade Tecnica, Lisbon (Portugal). Inst. Superior Tecnico

    1994-07-01

    The sawtooth crashes on JET display features which depend on beta. The main observation is a transient bulging of flux surfaces (duration inferior to 30 microsec.), which is predominantly on the low field side and extends to larger radii as beta increases. This phenomenon reaches the plasma boundary when beta{sub N} exceeds 0.5 and in these cases is followed by an ELM within 50 microsec. These sawtooth/ELM events limit plasma performance. Modelling of mode coupling shows qualitative agreement between observations of the structure of the sawtooth precursor and the calculated internal kink mode at high beta. (authors). 6 refs., 5 figs.

  18. Crash testing the largest experiment on Earth

    OpenAIRE

    Cauchi, Marija

    2015-01-01

    Under Europe lies a 27 km tunnel that is both the coldest and hottest place on Earth. The Large Hadron Collider (LHC) has already found out what gives mass to all the matter in the Universe. It is now trying to go even deeper into what makes up everything we see around us. Dr Marija Cauchi writes about her research that helped protect this atom smasher from itself. Photography by Jean Claude Vancell. http://www.um.edu.mt/think/crash-testing-the-largest-experiment-on-earth/

  19. Correlation between crash avoidance maneuvers and injury severity sustained by motorcyclists in single-vehicle crashes.

    Science.gov (United States)

    Wang, Chen; Lu, Linjun; Lu, Jian; Wang, Tao

    2016-01-01

    In order to improve motorcycle safety, this article examines the correlation between crash avoidance maneuvers and injury severity sustained by motorcyclists, under multiple precrash conditions. Ten-year crash data for single-vehicle motorcycle crashes from the General Estimates Systems (GES) were analyzed, using partial proportional odds models (i.e., generalized ordered logit models). The modeling results show that "braking (no lock-up)" is associated with a higher probability of increased severity, whereas "braking (lock-up)" is associated with a higher probability of decreased severity, under all precrash conditions. "Steering" is associated with a higher probability of reduced injury severity when other vehicles are encroaching, whereas it is correlated with high injury severity under other conditions. "Braking and steering" is significantly associated with a higher probability of low severity under "animal encounter and object presence," whereas it is surprisingly correlated with high injury severity when motorcycles are traveling off the edge of the road. The results also show that a large number of motorcyclists did not perform any crash avoidance maneuvers or conducted crash avoidance maneuvers that are significantly associated with high injury severity. In general, this study suggests that precrash maneuvers are an important factor associated with motorcyclists' injury severity. To improve motorcycle safety, training/educational programs should be considered to improve safety awareness and adjust driving habits of motorcyclists. Antilock brakes and such systems are also promising, because they could effectively prevent brake lock-up and assist motorcyclists in maneuvering during critical conditions. This study also provides valuable information for the design of motorcycle training curriculum.

  20. Two-fractal overlap time series: Earthquakes and market crashes

    Indian Academy of Sciences (India)

    velocity over the other and time series of stock prices. An anticipation method for some of the crashes have been proposed here, based on these observations. Keywords. Cantor set; time series; earthquake; market crash. PACS Nos 05.00; 02.50.-r; 64.60; 89.65.Gh; 95.75.Wx. 1. Introduction. Capturing dynamical patterns of ...

  1. Drug and alcohol crash risk : a case-control study.

    Science.gov (United States)

    2016-12-01

    This study used a case-control design to estimate the risk of crashes involving drivers using drugs, alcohol or both. Data was collected in Virginia Beach, Virginia, for 20 months. The study obtained biological measures on more than 3,000 crash...

  2. In pedestrian crashes, it's vehicle speed that matters the most

    Science.gov (United States)

    2000-05-13

    A recently prepared report on pedestrian injuries provides these two main findings: 1) regardless of age, pedestrians involved in crashes are more likely to be killed as vehicle speeds increase; and 2) in crashes at any speed, older pedestrians are m...

  3. Impact of connected vehicles on mitigating secondary crash risk

    Directory of Open Access Journals (Sweden)

    Hong Yang

    2017-09-01

    Full Text Available Reducing the risk of secondary crashes is a key goal for effective traffic incident management. However, only few countermeasures have been established in practices to achieve the goal. This is mainly due to the stochastic nature of both primary and secondary crashes. Given the emerging connected vehicle (CV technologies, it is highly likely that CVs will soon be able to communicate with each other through the ad-hoc wireless vehicular network. Information sharing among vehicles is deemed to change traffic operations and allow motorists for more proactive actions. Motorists who receive safety messages can be motivated to approach queues and incident sites with more caution. As a result of the improved situational awareness, the risk of secondary crashes is expected to be reduced. To examine whether this expectation is achievable or not, this study aims to assess the impact of connectivity on the risk of secondary crashes. A simulation-based modeling framework that enables vehicle-to-vehicle communication module was developed. Since crashes cannot be directly simulated in micro-simulation, the use of surrogate safety measures was proposed to capture vehicular conflicts as a proxy for secondary crash risk upstream of a primary crash site. An experimental study was conducted based on the developed simulation modeling framework. The results show that the use of connected vehicles can be a viable way to reduce the risk of secondary crashes. Their impact is expected to change with an increasing market penetration of connected vehicles.

  4. Prediction equation for vehicle-pedestrian crash and safety analysis ...

    African Journals Online (AJOL)

    The occurrences of vehicle-pedestrian crashes at signalized intersections were investigated using a 3 year (2004-2006) crash records of 82 signalized intersections in Accra, Kumasi, Tema, Sekondi-Takoradi and Tamale. The data were analyzed using Micro-computer Accident Analysis Package. Traffic flow characteristics ...

  5. Analysis of Traffic Crash Data in Kentucky (2012-2016).

    Science.gov (United States)

    2017-09-01

    This report documents an analysis of traffic crash data in Kentucky for the years of 2012 through 2016. A primary objective of this study was to determine average crash statistics for Kentucky highways. Rates were calculated for various types of high...

  6. Analysis of traffic crash data in Kentucky (2009-2013).

    Science.gov (United States)

    2014-09-01

    This report documents an analysis of traffic crash data in Kentucky for the years of 2009 through 2013. A primary objective of this study was to determine average crash statistics for Kentucky highways. Rates were calculated for various types of high...

  7. Robust collaborative process interactions under system crash and network failures

    NARCIS (Netherlands)

    Wang, Lei; Wombacher, Andreas; Ferreira Pires, Luis; van Sinderen, Marten J.; Chi, Chihung

    2013-01-01

    With the possibility of system crashes and network failures, the design of robust client/server interactions for collaborative process execution is a challenge. If a business process changes its state, it sends messages to the relevant processes to inform about this change. However, server crashes

  8. Social costs of road crashes : an international analysis.

    NARCIS (Netherlands)

    Wijnen, W. & Stipdonk, H.L.

    2016-01-01

    This paper provides an international overview of the most recent estimates of the social costs of road crashes: total costs, value per casualty and breakdown in cost components. The analysis is based on publications about the national costs of road crashes of 17 countries, of which ten high income

  9. Road Crashes in Addis Ababa, Ethiopia: Empirical Findings ...

    African Journals Online (AJOL)

    Nneka Umera-Okeke

    studies on road crashes forecasted road traffic fatalities to be the second ... Ethiopia's capital city – shares 60% out of the total number of vehicles in the ... network density and vehicle ownership, the country (Ethiopia) has been cited as ... crash related injury case confirmation. ..... to thank you in advance for your cooperation!

  10. School start times and teenage driver motor vehicle crashes.

    Science.gov (United States)

    Foss, Robert D; Smith, Richard L; O'Brien, Natalie P

    2018-04-26

    Shifting school start times to 8:30 am or later has been found to improve academic performance and reduce behavior problems. Limited research suggests this may also reduce adolescent driver motor vehicle crashes. A change in the school start time from 7:30 am to 8:45 am for all public high schools in one North Carolina county presented the opportunity to address this question with greater methodologic rigor. We conducted ARIMA interrupted time-series analyses to examine motor vehicle crash rates of high school age drivers in the intervention county and 3 similar comparison counties with comparable urban-rural population distribution. To focus on crashes most likely to be affected, we limited analysis to crashes involving 16- & 17-year-old drivers occurring on days when school was in session. In the intervention county, there was a 14% downward shift in the time-series following the 75 min delay in school start times (p = .076). There was no change approaching statistical significance in any of the other three counties. Further analysis indicated marked, statistically significant shifts in hourly crash rates in the intervention county, reflecting effects of the change in school start time on young driver exposure. Crashes from 7 to 7:59 am decreased sharply (-25%, p = .008), but increased similarly from 8 to 8:59 am (21%, p = .004). Crashes from 2 to 2:59 pm declined dramatically (-48%, p = .000), then increased to a lesser degree from 3 to 3:59 pm (32%, p = .024) and non-significantly from 4 to 4:59 (19%, p = .102). There was no meaningful change in early morning or nighttime crashes, when drowsiness-induced crashes might have been expected to be most common. The small decrease in crashes among high school age drivers following the shift in school start time is consistent with the findings of other studies of teen driver crashes and school start times. All these studies, including the present one, have limitations, but the similar

  11. Fire deaths in aircraft without the crashworthy fuel system.

    Science.gov (United States)

    Springate, C S; McMeekin, R R; Ruehle, C J

    1989-10-01

    Cases reported to the Armed Forces Institute of Pathology were examined for occupants of helicopters without the crashworthy fuel system (CWFS) who survived crashes but died as a result of postcrash fires. There were 16 fire deaths in the 9 such accidents which occurred between January 1976 and April 1984. All of these victims would have survived if there had been no postcrash fire. Partial body destruction by fire probably prevented inclusion of many other cases. The dramatic reduction in fire deaths and injuries due to installation of the CWFS in Army helicopters is discussed. The author concludes that fire deaths and injuries in aircraft accidents could almost be eliminated by fitting current and future aircraft with the CWFS.

  12. A probabilistic approach for evaluation of load time history of an aircraft impact

    International Nuclear Information System (INIS)

    Zorn, N.F.; Schueller, G.I.; Riera, J.D.

    1981-01-01

    In the context of an overall structural realiability study for a containment located in the F.R. Germany the external load case aircraft impact is investigated. Previous investigations have been based on deterministic evaluations of the load time history. However, a close analysis of the input parameters, such as the mass distribution, the stiffness of the aircraft, the impact velocity and the impact angle reveal their random properties. This in turn leads to a stochastic load time history the parameters of which have been determined in this study. In other words, the randomness of the input parameters are introduced in the calculation of the load time history and their influence with regard to the load magnitude and frequency content is determined. The statistical parameters such as the mean values and the standard deviation of the mechanical properties are evaluated directly from the design plans of the manufacturer for the aircraft Phantom F4-F. This includes rupture loads, mass distributions etc.. The probability distributions of the crash velocity and impact angle are based on a thorough statistical evaluation of the crash histories of the airplane under consideration. Reference was made only to crashes which occurred in the F.R. Germany. (orig.)

  13. Aurora Flight Sciences' Perseus B Remotely Piloted Aircraft in Flight

    Science.gov (United States)

    1998-01-01

    project. The Perseus Proof-Of-Concept aircraft first flew in November 1991 and made three low-altitude flights within a month to validate the Perseus aerodynamic model and flight control systems. Next came the redesigned Perseus A, which incorporated a closed-cycle combustion system that mixed oxygen carried aboard the aircraft with engine exhaust to compensate for the thin air at high altitudes. The Perseus A was towed into the air by a ground vehicle and its engine started after it became airborne. Prior to landing, the engine was stopped, the propeller locked in horizontal position, and the Perseus A glided to a landing on its unique bicycle-type landing gear. Two Perseus A aircraft were built and made 21 flights in 1993-1994. One of the Perseus A aircraft reached over 50,000 feet in altitude on its third test flight. Although one of the Perseus A aircraft was destroyed in a crash after a vertical gyroscope failed in flight, the other aircraft completed its test program and remains on display at Aurora's facility in Manassas. Perseus B first flew Oct. 7, 1994, and made two flights in 1996 before being damaged in a hard landing on the dry lakebed after a propeller shaft failure. After a number of improvements and upgrades-including extending the original 58.5-foot wingspan to 71.5 feet to enhance high-altitude performance--the Perseus B returned to Dryden in the spring of 1998 for a series of four flights. Thereafter, a series of modifications were made including external fuel pods on the wing that more than doubled the fuel capacity to 100 gallons. Engine power was increased by more than 20 percent by boosting the turbocharger output. Fuel consumption was reduced with fuel control modifications and a leaner fuel-air mixture that did not compromise power. The aircraft again crashed on Oct. 1, 1999, near Barstow, California, suffering moderate damage to the aircraft but no property damage, fire, or injuries in the area of the crash. Perseus B is flown remotely by a pilot

  14. Copycats in Pilot Aircraft-Assisted Suicides after the Germanwings Incident

    Directory of Open Access Journals (Sweden)

    Tanja Laukkala

    2018-03-01

    Full Text Available Aircraft-assisted pilot suicide is a rare but serious phenomenon. The aim of this study was to evaluate changes in pilot aircraft-assisted suicide risks, i.e., a copycat effect, in the U.S. and Germany after the Germanwings 2015 incident in the French Alps. Aircraft-assisted pilot suicides were searched in the U.S. National Transportation Safety Board (NTSB accident investigation database and in the German Bundestelle für Flugunfalluntersuchung (BFU Reports of Investigation database five years before and two years after the deliberate crash of the Germanwings flight into the French Alps in 2015. The relative risk (RR of the aircraft-assisted pilot suicides was calculated. Two years after the incident, three out of 454 (0.66% fatal incidents were aircraft-assisted suicides compared with six out of 1292 (0.46% in the prior five years in the NTSB database. There were no aircraft-assisted pilot suicides in the German database during the two years after or five years prior to the Germanwings crash. The relative aircraft-assisted pilot suicide risk for the U.S. was 1.4 (95% CI 0.3–4.2 which was not statistically significant. Six of the pilots who died by suicide had told someone of their suicidal intentions. We consider changes in the rate to be within a normal variation. Responsible media coverage of aircraft incidents is important due to the large amount of publicity that these events attract.

  15. Copycats in Pilot Aircraft-Assisted Suicides after the Germanwings Incident

    Science.gov (United States)

    Vuorio, Alpo; Bor, Robert; Budowle, Bruce; Navathe, Pooshan; Pukkala, Eero; Sajantila, Antti

    2018-01-01

    Aircraft-assisted pilot suicide is a rare but serious phenomenon. The aim of this study was to evaluate changes in pilot aircraft-assisted suicide risks, i.e., a copycat effect, in the U.S. and Germany after the Germanwings 2015 incident in the French Alps. Aircraft-assisted pilot suicides were searched in the U.S. National Transportation Safety Board (NTSB) accident investigation database and in the German Bundestelle für Flugunfalluntersuchung (BFU) Reports of Investigation database five years before and two years after the deliberate crash of the Germanwings flight into the French Alps in 2015. The relative risk (RR) of the aircraft-assisted pilot suicides was calculated. Two years after the incident, three out of 454 (0.66%) fatal incidents were aircraft-assisted suicides compared with six out of 1292 (0.46%) in the prior five years in the NTSB database. There were no aircraft-assisted pilot suicides in the German database during the two years after or five years prior to the Germanwings crash. The relative aircraft-assisted pilot suicide risk for the U.S. was 1.4 (95% CI 0.3–4.2) which was not statistically significant. Six of the pilots who died by suicide had told someone of their suicidal intentions. We consider changes in the rate to be within a normal variation. Responsible media coverage of aircraft incidents is important due to the large amount of publicity that these events attract. PMID:29534475

  16. The October 2014 United States Treasury bond flash crash and the contributory effect of mini flash crashes.

    Directory of Open Access Journals (Sweden)

    Zachary S Levine

    Full Text Available We investigate the causal uncertainty surrounding the flash crash in the U.S. Treasury bond market on October 15, 2014, and the unresolved concern that no clear link has been identified between the start of the flash crash at 9:33 and the opening of the U.S. equity market at 9:30. We consider the contributory effect of mini flash crashes in equity markets, and find that the number of equity mini flash crashes in the three-minute window between market open and the Treasury Flash Crash was 2.6 times larger than the number experienced in any other three-minute window in the prior ten weekdays. We argue that (a this statistically significant finding suggests that mini flash crashes in equity markets both predicted and contributed to the October 2014 U.S. Treasury Bond Flash Crash, and (b mini-flash crashes are important phenomena with negative externalities that deserve much greater scholarly attention.

  17. The October 2014 United States Treasury bond flash crash and the contributory effect of mini flash crashes.

    Science.gov (United States)

    Levine, Zachary S; Hale, Scott A; Floridi, Luciano

    2017-01-01

    We investigate the causal uncertainty surrounding the flash crash in the U.S. Treasury bond market on October 15, 2014, and the unresolved concern that no clear link has been identified between the start of the flash crash at 9:33 and the opening of the U.S. equity market at 9:30. We consider the contributory effect of mini flash crashes in equity markets, and find that the number of equity mini flash crashes in the three-minute window between market open and the Treasury Flash Crash was 2.6 times larger than the number experienced in any other three-minute window in the prior ten weekdays. We argue that (a) this statistically significant finding suggests that mini flash crashes in equity markets both predicted and contributed to the October 2014 U.S. Treasury Bond Flash Crash, and (b) mini-flash crashes are important phenomena with negative externalities that deserve much greater scholarly attention.

  18. A Crashworthiness Analysis with Emphasis on the Fire Hazard: U.S. and Selected Foreign Turbine Aircraft Accidents, 1964-1974

    Science.gov (United States)

    1976-07-01

    and crash landed-in the lake,. Aytotal of 315 dead seagulls was found in the area. One engine compressor unit was 20% filled with bird debris, the...Pan American, Sydney, Australia LThe aircraft struck a flock of seagulls during the takeoff run and ingested birds in No. 2 and No. 3 engines, causing a

  19. Gasoline prices and traffic crashes in Alabama, 1999-2009.

    Science.gov (United States)

    Chi, Guangqing; McClure, Timothy E; Brown, David B

    2012-09-01

    The price of gasoline has been found to be negatively associated with traffic crashes in a limited number of studies. However, most of the studies have focused either on fatal crashes only or on all crashes but measured over a very short time period. In this study, we examine gasoline price effects on all traffic crashes by demographic groups in the state of Alabama from 1999 to 2009. Using negative binomial regression techniques to examine monthly data from 1999 to 2009 in the state of Alabama, we estimate the effects of changes in gasoline price on changes in automobile crashes. We also examine how these effects differ by age group (16-20, 21-25, 26-30, 31-64, and 65+), gender (male and female), and race/ethnicity (non-Hispanic white, non-Hispanic black, and Hispanic). The results show that gasoline prices have both short-term and long-term effects on reducing total traffic crashes and crashes of each age, gender, and race/ethnicity group (except Hispanic due to data limitations). The short-term and long-term effects are not statistically different for each individual demographic group. Gasoline prices have a stronger effect in reducing crashes involving drivers aged 16 to 20 than crashes involving drivers aged 31 to 64 and 65+ in the short term; the effects, however, are not statistically different across other demographic groups. Although gasoline price increases are not favored, our findings show that gasoline price increases (or decreases) are associated with reductions (or increases) in the incidence of traffic crashes. If gasoline prices had remained at the 1999 level of $1.41 from 1999 to 2009, applying the estimated elasticities would result in a predicted increase in total crashes of 169,492 (or 11.3%) from the actual number of crashes. If decision makers wish to reduce traffic crashes, increasing gasoline taxes is a possible option-however, doing so would increase travel costs and lead to equity concerns. These findings may help to shape transportation

  20. Crashes and near-crashes on horizontal curves along rural two-lane highways: Analysis of naturalistic driving data.

    Science.gov (United States)

    Wang, Bo; Hallmark, Shauna; Savolainen, Peter; Dong, Jing

    2017-12-01

    Prior research has shown the probability of a crash occurring on horizontal curves to be significantly higher than on similar tangent segments, and a disproportionally higher number of curve-related crashes occurred in rural areas. Challenges arise when analyzing the safety of horizontal curves due to imprecision in integrating information as to the temporal and spatial characteristics of each crash with specific curves. The second Strategic Highway Research Program(SHRP 2) conducted a large-scale naturalistic driving study (NDS),which provides a unique opportunity to better understand the contributing factors leading to crash or near-crash events. This study utilizes high-resolution behavioral data from the NDS to identify factors associated with 108 safety critical events (i.e., crashes or near-crashes) on rural two-lane curves. A case-control approach is utilized wherein these events are compared to 216 normal, baseline-driving events. The variables examined in this study include driver demographic characteristics, details of the traffic environment and roadway geometry, as well as driver behaviors such as in-vehicle distractions. Logistic regression models are estimated to discern those factors affecting the likelihood of a driver being crash-involved. These factors include high-risk behaviors, such as speeding and visual distractions, as well as curve design elements and other roadway characteristics such as pavement surface conditions. This paper successfully integrated driver behavior, vehicle characteristics, and roadway environments into the same model. Logistic regression model was found to be an effective way to investigate crash risks using naturalistic driving data. This paper revealed a number of contributing factors to crashes on rural two-lane curves, which has important implications in traffic safety policy and curve geometry design. This paper also discussed limitations and lessons learned from working with the SHRP 2 NDS data. It will benefit

  1. Modeling crash injury severity by road feature to improve safety.

    Science.gov (United States)

    Penmetsa, Praveena; Pulugurtha, Srinivas S

    2018-01-02

    The objective of this research is 2-fold: to (a) model and identify critical road features (or locations) based on crash injury severity and compare it with crash frequency and (b) model and identify drivers who are more likely to contribute to crashes by road feature. Crash data from 2011 to 2013 were obtained from the Highway Safety Information System (HSIS) for the state of North Carolina. Twenty-three different road features were considered, analyzed, and compared with each other as well as no road feature. A multinomial logit (MNL) model was developed and odds ratios were estimated to investigate the effect of road features on crash injury severity. Among the many road features, underpass, end or beginning of a divided highway, and on-ramp terminal on crossroad are the top 3 critical road features. Intersection crashes are frequent but are not highly likely to result in severe injuries compared to critical road features. Roundabouts are least likely to result in both severe and moderate injuries. Female drivers are more likely to be involved in crashes at intersections (4-way and T) compared to male drivers. Adult drivers are more likely to be involved in crashes at underpasses. Older drivers are 1.6 times more likely to be involved in a crash at the end or beginning of a divided highway. The findings from this research help to identify critical road features that need to be given priority. As an example, additional advanced warning signs and providing enlarged or highly retroreflective signs that grab the attention of older drivers may help in making locations such as end or beginning of a divided highway much safer. Educating drivers about the necessary skill sets required at critical road features in addition to engineering solutions may further help them adopt safe driving behaviors on the road.

  2. Drug and Alcohol Involvement in Four Types of Fatal Crashes*

    Science.gov (United States)

    Romano, Eduardo; Voas, Robert B.

    2011-01-01

    Objective: The aim of this study was to explore the relationship of drunk and drugged driving to the occurrence of fatal crashes associated with speeding, failure to obey/yield, inattention, and seat belt nonuse. Method: We examined data for fatally injured drivers involved in single-vehicle crashes killed in states in which more than 79% of the drivers were tested for drugs other than alcohol and had a known result. Results: About 25% of the drivers tested positive for drugs, a figure almost double that estimated by the 2007 National Roadside Survey. Cannabinoids and stimulants each contributed to about 23% of the drug-positive results (6% among all fatally injured single-vehicle drivers). Stimulants more than cannabinoids were found to be associated with the four types of crashes under study. Some drugs showed a protective effect over the four crash types under study. Significant interactions between drugs and alcohol were observed. Stimulants contributed to the different types of fatal crashes irrespective of the levels of alcohol consumed by the drivers. Conclusions: This study provides further evidence of a link between drug consumption and fatal crashes. It also opens the door to some interesting and sometimes unexpected questions regarding the way drugs contribute to crashes, which we found varies depending on the type of crash considered, the class of drug, and the presence of alcohol. Research is also needed on drugs that could have a protective effect on the occurrence of fatal crashes. These findings could be highly relevant to the design of drug-related traffic laws and programs targeted at curbing drugged driving. PMID:21683038

  3. Aircraft operations management manual

    Science.gov (United States)

    1992-01-01

    The NASA aircraft operations program is a multifaceted, highly diverse entity that directly supports the agency mission in aeronautical research and development, space science and applications, space flight, astronaut readiness training, and related activities through research and development, program support, and mission management aircraft operations flights. Users of the program are interagency, inter-government, international, and the business community. This manual provides guidelines to establish policy for the management of NASA aircraft resources, aircraft operations, and related matters. This policy is an integral part of and must be followed when establishing field installation policy and procedures covering the management of NASA aircraft operations. Each operating location will develop appropriate local procedures that conform with the requirements of this handbook. This manual should be used in conjunction with other governing instructions, handbooks, and manuals.

  4. Overview of the Transport Rotorcraft Airframe Crash Testbed (TRACT) Full Scale Crash Tests

    Science.gov (United States)

    Annett, Martin; Littell, Justin

    2015-01-01

    The Transport Rotorcraft Airframe Crash Testbed (TRACT) full-scale tests were performed at NASA Langley Research Center's Landing and Impact Research Facility in 2013 and 2014. Two CH-46E airframes were impacted at 33-ft/s forward and 25-ft/s vertical combined velocities onto soft soil, which represents a severe, but potentially survivable impact scenario. TRACT 1 provided a baseline set of responses, while TRACT 2 included retrofits with composite subfloors and other crash system improvements based on TRACT 1. For TRACT 2, a total of 18 unique experiments were conducted to evaluate Anthropomorphic Test Devices (ATD) responses, seat and restraint performance, cargo restraint effectiveness, patient litter behavior, and activation of emergency locator transmitters and crash sensors. Combinations of Hybrid II, Hybrid III, and ES-2 ATDs were placed in forward and side facing seats and occupant results were compared against injury criteria. The structural response of the airframe was assessed based on accelerometers located throughout the airframe and using three-dimensional photogrammetric techniques. Analysis of the photogrammetric data indicated regions of maximum deflection and permanent deformation. The response of TRACT 2 was noticeably different in the horizontal direction due to changes in the cabin configuration and soil surface, with higher acceleration and damage occurring in the cabin. Loads from ATDs in energy absorbing seats and restraints were within injury limits. Severe injury was likely for ATDs in forward facing passenger seats.

  5. Minor Crashes and ‘Whiplash’ in the United States

    OpenAIRE

    Bartsch, Adam J.; Gilbertson, Lars G.; Prakash, Vikas; Morr, Douglas R.; Wiechel, John F.

    2008-01-01

    In the United States there is currently a paucity of available real world minor rear crash data with struck vehicle delta-V, or speed change, less than or equal to 15 kilometers per hour. These data are essential as researchers attempt to define ‘whiplash’ injury risk potential in these minor crashes. This study analyzed a new set of 105 U.S. minor rear aligned crashes between passenger vehicles. Mean struck vehicle delta-V and acceleration were 6.3 km/h (s.d. = 2.1 km/h) and 1.4g (s.d. = 0.5...

  6. Projecting Fatalities in Crashes Involving Older Drivers, 2000-2025

    Energy Technology Data Exchange (ETDEWEB)

    Hu, P.S.

    2001-03-23

    As part of this research effort, we developed a new methodology for projecting elderly traffic crash fatalities. This methodology separates exposure to crashes from crash risk per se, and further divides exposure into two components, the number of miles driven and the likelihood of being a driver. This component structure permits conceptually different determinants of traffic fatalities to be projected separately and has thorough motivation in behavioral theory. It also permits finer targeting of particular aspects of projections that need improvement and closer linking of projections to possible policy instruments for influencing them.

  7. Construct exploit constraint in crash analysis by bypassing canary

    Science.gov (United States)

    Huang, Ning; Huang, Shuguang; Huang, Hui; Chang, Chao

    2017-08-01

    Selective symbolic execution is a common program testing technology. Developed on the basis of it, some crash analysis systems are often used to test the fragility of the program by constructing exploit constraints, such as CRAX. From the study of crash analysis based on symbolic execution, this paper find that this technology cannot bypass the canary stack protection mechanisms. This paper makes the improvement uses the API hook in Linux. Experimental results show that the use of API hook can effectively solve the problem that crash analysis cannot bypass the canary protection.

  8. Frequency Analysis of Aircraft hazards for License Application

    Energy Technology Data Exchange (ETDEWEB)

    K. Ashley

    2006-10-24

    The preclosure safety analysis for the monitored geologic repository at Yucca Mountain must consider the hazard that aircraft may pose to surface structures. Relevant surface structures are located beneath the restricted airspace of the Nevada Test Site (NTS) on the eastern slope of Yucca Mountain, near the North Portal of the Exploratory Studies Facility Tunnel (Figure 1). The North Portal is located several miles from the Nevada Test and Training Range (NTTR), which is used extensively by the U.S. Air Force (USAF) for training and test flights (Figure 1). The NTS airspace, which is controlled by the U.S. Department of Energy (DOE) for NTS activities, is not part of the NTTR. Agreements with the DOE allow USAF aircraft specific use of the airspace above the NTS (Reference 2.1.1 [DIRS 103472], Section 3.1.1 and Appendix A, Section 2.1; and Reference 2.1.2 [DIRS 157987], Sections 1.26 through 1.29). Commercial, military, and general aviation aircraft fly within several miles to the southwest of the repository site in the Beatty Corridor, which is a broad air corridor that runs approximately parallel to U.S. Highway 95 and the Nevada-California border (Figure 2). These aircraft and other aircraft operations are identified and described in ''Identification of Aircraft Hazards'' (Reference 2.1.3, Sections 6 and 8). The purpose of this analysis is to estimate crash frequencies for aircraft hazards identified for detailed analysis in ''Identification of Aircraft Hazards'' (Reference 2.1.3, Section 8). Reference 2.1.3, Section 8, also identifies a potential hazard associated with electronic jamming, which will be addressed in this analysis. This analysis will address only the repository and not the transportation routes to the site. The analysis is intended to provide the basis for: (1) Categorizing event sequences related to aircraft hazards; (2) Identifying design or operational requirements related to aircraft hazards.

  9. Suicide plane crash against nuclear power plants

    International Nuclear Information System (INIS)

    Richard, A.

    2002-01-01

    Cea (French atomic energy commission) and EDF (Electricity of France) are reassessing their safety standards concerning suicide plane attacks against nuclear facilities. The general idea is to study the non-linear behaviour of reinforced concrete in case of mechanical impact. American studies carried out in 1988 show that a F-14 phantom crashing into a 3,6 meter thick wall at a speed of 774 km/h penetrates only the first 5 cm of the wall. More recent studies performed in Germany and based on computerized simulations show that the reactor containment can sustain impacts from a F15 plane or even from a 747-Boeing but contiguous buildings like the one which houses spent fuels might be more easily damaged because of their metal roofing. (A.C.)

  10. A multinomial-logit ordered-probit model for jointly analyzing crash avoidance maneuvers and crash severity

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    ' propensity to engage in various corrective maneuvers in the case of the critical event of vehicle travelling. Five lateral and speed control maneuvers are considered: “braking”, “steering”, “braking & steering”, and “other maneuvers”, in addition to a “no action” option. The analyzed data are retrieved from...... the United States National Automotive Sampling System General Estimates System (GES) crash database for the years 2005-2009. Results show (i) the correlation between crash avoidance maneuvers and crash severity, and (ii) the link between drivers' attributes, risky driving behavior, road characteristics...

  11. Predicting visibility of aircraft.

    Directory of Open Access Journals (Sweden)

    Andrew Watson

    Full Text Available Visual detection of aircraft by human observers is an important element of aviation safety. To assess and ensure safety, it would be useful to be able to be able to predict the visibility, to a human observer, of an aircraft of specified size, shape, distance, and coloration. Examples include assuring safe separation among aircraft and between aircraft and unmanned vehicles, design of airport control towers, and efforts to enhance or suppress the visibility of military and rescue vehicles. We have recently developed a simple metric of pattern visibility, the Spatial Standard Observer (SSO. In this report we examine whether the SSO can predict visibility of simulated aircraft images. We constructed a set of aircraft images from three-dimensional computer graphic models, and measured the luminance contrast threshold for each image from three human observers. The data were well predicted by the SSO. Finally, we show how to use the SSO to predict visibility range for aircraft of arbitrary size, shape, distance, and coloration.

  12. Resistance ability evaluation of safety-related structures for the simulated aircraft accident

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Jin; Kim, Sung Woon; Choi, Jang Kyu [Daewoo E and C Co., Ltd., Suwon (Korea, Republic of)] (and others)

    2003-03-15

    Aircraft accidents on nuclear safety-related structures can cause severe damage to the safety of NPP(Nuclear Power Plant)s. To assess the safety of nuclear safety-related structures, the local damage and the dynamic response of global structures should be investigated together. This study have compared several local damage assessment formulas suggested for aircraft as an impactor, and have set the assessment system of local damage for impact-proof design of NPP containment buildings. And the local damage of nuclear safety-related structures in operation in Korea for commercial aircraft as impactor have been estimated. Impact load-time functions of the aircraft crash have been decided to assessment the safety of nuclear safety-related structures against the intentional colliding of commercial aircraft. Boeing 747 and Boeing 767 is selected as target aircraft based on the operation frequencies and weights. Comparison of the fire analysis methods showed that the method considering heat convection and radiation is adequate for the temperature analysis of the aircraft fuel fire. Finally, the study covered the analysis of the major structural drawings and design drawings with which three-dimensional finite element model analysis is expected to be performed.

  13. MOTORCYCLE CRASH PREDICTION MODEL FOR NON-SIGNALIZED INTERSECTIONS

    Directory of Open Access Journals (Sweden)

    S. HARNEN

    2003-01-01

    Full Text Available This paper attempts to develop a prediction model for motorcycle crashes at non-signalized intersections on urban roads in Malaysia. The Generalized Linear Modeling approach was used to develop the model. The final model revealed that an increase in motorcycle and non-motorcycle flows entering an intersection is associated with an increase in motorcycle crashes. Non-motorcycle flow on major road had the greatest effect on the probability of motorcycle crashes. Approach speed, lane width, number of lanes, shoulder width and land use were also found to be significant in explaining motorcycle crashes. The model should assist traffic engineers to decide the need for appropriate intersection treatment that specifically designed for non-exclusive motorcycle lane facilities.

  14. Motorcycle crash causes and outcomes: pilot study : traffic tech.

    Science.gov (United States)

    2010-08-01

    The number of motorcyclist crash-related fatalities has more than doubled during the past 10 years. In the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU), Congress directed the Secretary of Transport...

  15. Preliminary plan for case-control crash risk study

    Science.gov (United States)

    2002-01-31

    The goal of the Federal Motor Carrier Safety Administration (FMCSA) is to reduce commercial vehicle-related fatalities and injuries. This is achieved through a thorough understanding of crash characteristics, precursors, and risk factors. This will h...

  16. Solutions for acceleration measurement in vehicle crash tests

    Science.gov (United States)

    Dima, D. S.; Covaciu, D.

    2017-10-01

    Crash tests are useful for validating computer simulations of road traffic accidents. One of the most important parameters measured is the acceleration. The evolution of acceleration versus time, during a crash test, form a crash pulse. The correctness of the crash pulse determination depends on the data acquisition system used. Recommendations regarding the instrumentation for impact tests are given in standards, which are focused on the use of accelerometers as impact sensors. The goal of this paper is to present the device and software developed by authors for data acquisition and processing. The system includes two accelerometers with different input ranges, a processing unit based on a 32-bit microcontroller and a data logging unit with SD card. Data collected on card, as text files, is processed with a dedicated software running on personal computers. The processing is based on diagrams and includes the digital filters recommended in standards.

  17. Crash Prediction and Risk Evaluation Based on Traffic Analysis Zones

    Directory of Open Access Journals (Sweden)

    Cuiping Zhang

    2014-01-01

    Full Text Available Traffic safety evaluation for traffic analysis zones (TAZs plays an important role in transportation safety planning and long-range transportation plan development. This paper aims to present a comprehensive analysis of zonal safety evaluation. First, several criteria are proposed to measure the crash risk at zonal level. Then these criteria are integrated into one measure-average hazard index (AHI, which is used to identify unsafe zones. In addition, the study develops a negative binomial regression model to statistically estimate significant factors for the unsafe zones. The model results indicate that the zonal crash frequency can be associated with several social-economic, demographic, and transportation system factors. The impact of these significant factors on zonal crash is also discussed. The finding of this study suggests that safety evaluation and estimation might benefit engineers and decision makers in identifying high crash locations for potential safety improvements.

  18. Finite Element Crash Simulations and Impact-Induced Injuries

    Directory of Open Access Journals (Sweden)

    Jaroslav Mackerle

    1999-01-01

    Full Text Available This bibliography lists references to papers, conference proceedings and theses/dissertations dealing with finite element simulations of crashes, impact-induced injuries and their protection that were published in 1980–1998. 390 citations are listed.

  19. Pedestrian and bicycle crash data analysis : 2005-2010.

    Science.gov (United States)

    2012-04-03

    The safety of pedestrians and bicyclists using the roadway is an increasing concern for the Michigan Department of Transportation (MDOT). This report summarizes data for motor vehicle crashes involving pedestrians and bicyclists in Michigan from 2005...

  20. Crash Data Improvement Program : An RSPCB Peer Exchange

    Science.gov (United States)

    2011-08-04

    This report provides a summary of the Crash Data Improvement Program (CDIP) peer : exchange sponsored by the Federal Highway Administrations (FHWA) Office of Safety : on August 4, 2011. The peer exchange was hosted in conjunction with the annual :...

  1. Relationship between organisational safety culture dimensions and crashes.

    Science.gov (United States)

    Varmazyar, Sakineh; Mortazavi, Seyed Bagher; Arghami, Shirazeh; Hajizadeh, Ebrahim

    2016-01-01

    Knowing about organisational safety culture in public transportation system can provide an appropriate guide to establish effective safety measures and interventions to improve safety at work. The aim of this study was investigation of association between safety culture dimensions (leadership styles and company values, usage of crashes information and prevention programmes, management commitment and safety policy, participation and control) with involved self-reported crashes. The associations were considered through Spearman correlation, Pearson chi-square test and logistic regression. The results showed an association among self-reported crashes (occurrence or non-occurrence) and factors including leadership styles and company values; management commitment and safety policy; and control. Moreover, it was found a negative correlation and an odds ratio less than one between control and self-reported crashes.

  2. Maintenance program decision-making utilizing crash data.

    Science.gov (United States)

    2013-07-01

    This document describes methods that may be used by UDOT Maintenance personnel to improve highway safety. Four programs have been recommended using crash data to make more informed decisions concerning maintenance programs as follows: : Snow & Ic...

  3. Why Do Markets Crash? Bitcoin Data Offers Unprecedented Insights

    Science.gov (United States)

    Donier, Jonathan; Bouchaud, Jean-Philippe

    2015-01-01

    Crashes have fascinated and baffled many canny observers of financial markets. In the strict orthodoxy of the efficient market theory, crashes must be due to sudden changes of the fundamental valuation of assets. However, detailed empirical studies suggest that large price jumps cannot be explained by news and are the result of endogenous feedback loops. Although plausible, a clear-cut empirical evidence for such a scenario is still lacking. Here we show how crashes are conditioned by the market liquidity, for which we propose a new measure inspired by recent theories of market impact and based on readily available, public information. Our results open the possibility of a dynamical evaluation of liquidity risk and early warning signs of market instabilities, and could lead to a quantitative description of the mechanisms leading to market crashes. PMID:26448333

  4. Evaluating the police service quality for handling traffic crash reporting

    DEFF Research Database (Denmark)

    Janstrup, Kira Hyldekær; Kaplan, Sigal; Barfod, Michael Bruhn

    2017-01-01

    Purpose The phenomenon of traffic crash under-reporting has been extensively documented in terms of its extent, but not equally analysed in terms of its reasons. As police distrust has been recently identified as a major reason for crash under-reporting, the purpose of this paper is to look...... at the police service quality for handling the reporting of traffic crashes. Design/methodology/approach This study introduces a novel approach to evaluate service quality that combines multi-criteria decision analysis (MCDA) with latent class analysis (LCA). Moreover, this study presents the design of a web......-based survey on the basis of the SERVQUAL approach to detecting strengths, opportunities and threats with crash reporting to the police at a strategic level. Transportation stakeholders (e.g. researchers, authorities, consultants, NGO representatives, suppliers) with an interest in traffic safety in Denmark...

  5. Why Do Markets Crash? Bitcoin Data Offers Unprecedented Insights.

    Science.gov (United States)

    Donier, Jonathan; Bouchaud, Jean-Philippe

    2015-01-01

    Crashes have fascinated and baffled many canny observers of financial markets. In the strict orthodoxy of the efficient market theory, crashes must be due to sudden changes of the fundamental valuation of assets. However, detailed empirical studies suggest that large price jumps cannot be explained by news and are the result of endogenous feedback loops. Although plausible, a clear-cut empirical evidence for such a scenario is still lacking. Here we show how crashes are conditioned by the market liquidity, for which we propose a new measure inspired by recent theories of market impact and based on readily available, public information. Our results open the possibility of a dynamical evaluation of liquidity risk and early warning signs of market instabilities, and could lead to a quantitative description of the mechanisms leading to market crashes.

  6. Why Do Markets Crash? Bitcoin Data Offers Unprecedented Insights.

    Directory of Open Access Journals (Sweden)

    Jonathan Donier

    Full Text Available Crashes have fascinated and baffled many canny observers of financial markets. In the strict orthodoxy of the efficient market theory, crashes must be due to sudden changes of the fundamental valuation of assets. However, detailed empirical studies suggest that large price jumps cannot be explained by news and are the result of endogenous feedback loops. Although plausible, a clear-cut empirical evidence for such a scenario is still lacking. Here we show how crashes are conditioned by the market liquidity, for which we propose a new measure inspired by recent theories of market impact and based on readily available, public information. Our results open the possibility of a dynamical evaluation of liquidity risk and early warning signs of market instabilities, and could lead to a quantitative description of the mechanisms leading to market crashes.

  7. Traffic crash involvement: experiential driving knowledge and stressful contextual antecedents.

    Science.gov (United States)

    Legree, Peter J; Heffner, Tonia S; Psotka, Joseph; Martin, Daniel E; Medsker, Gina J

    2003-02-01

    Researchers have rarely examined stressful environments and psychological characteristics as predictors of driving behavior in the same study. The authors hypothesized that (a) safer drivers more accurately assess physical and emotional traffic hazards and (b) stress and emotional states elevate crash risk. The hypotheses were evaluated with procedural and declarative tacit driving knowledge tests requiring assessment of emotional and contextual hazards and with accident reports describing crash antecedents, including stressful events and environmental conditions. Analyses identified separate driving knowledge factors corresponding to emotional and contextual hazards that were significantly related to the crash criteria. Accident report analyses show that stress significantly elevates at-fault crash risk. The results demonstrate the importance of experiential knowledge acquired without instruction (procedural or tacit knowledge) and provide safety recommendations.

  8. Heavy Vehicle Crash Characteristics in Oman; 2009–2011

    Directory of Open Access Journals (Sweden)

    Islam Al-Bulushi

    2015-05-01

    Full Text Available In recent years, Oman has seen a shift in the burden of diseases towards road accidents. The main objective of this paper, therefore, is to describe key characteristics of heavy vehicle crashes in Oman and identify the key driving behaviours that influence fatality risks. Crash data from January 2009 to December 2011 were examined and it was found that, of the 22,543 traffic accidents that occurred within this timeframe, 3,114 involved heavy vehicles. While the majority of these crashes were attributed to driver behaviours, a small proportion was attributed to other factors. The results of the study indicate that there is a need for a more thorough crash investigation process in Oman. Future research should explore the reporting processes used by the Royal Oman Police, cultural influences on heavy vehicle operations in Oman and improvements to the current licensing system.

  9. Data mining the Kansas traffic-crash database : final report.

    Science.gov (United States)

    2009-08-01

    Traffic crashes results from the interaction of different parameters which includes highway geometrics, traffic characteristics and human factors. Geometric variables include number of lanes, lane width, median width, shoulder width, roadway section ...

  10. Data mining the Kansas traffic-crash database : summary.

    Science.gov (United States)

    2009-08-01

    Traffic crashes results from the interaction of different parameters which includes highway geometrics, traffic : characteristics and human factors. Geometric variables include number of lanes, lane width, median width, shoulder : width, roadway sect...

  11. Geo-demographic analysis of fatal motorcycle crashes

    Science.gov (United States)

    2001-01-01

    The objective of this study is to analyze the combined motor vehicle crash data from the Fatality Analysis Reporting System (FARS) with the Claritas geo-demographic database from the lifestyle perspective to determine the appropriate media to use in ...

  12. SOLAR AIRCRAFT DESIGN

    OpenAIRE

    RAHMATI, Sadegh; GHASED, Amir

    2015-01-01

    Abstract. Generally domain Aircraft uses conventional fuel. These fuel having limited life, high cost and pollutant. Also nowadays price of petrol and other fuels are going to be higher, because of scarcity of those fuels. So there is great demand of use of non-exhaustible unlimited source of energy like solar energy. Solar aircraft is one of the ways to utilize solar energy. Solar aircraft uses solar panel to collect the solar radiation for immediate use but it also store the remaining part ...

  13. Minor Crashes and ‘Whiplash’ in the United States

    Science.gov (United States)

    Bartsch, Adam J.; Gilbertson, Lars G.; Prakash, Vikas; Morr, Douglas R.; Wiechel, John F.

    2008-01-01

    In the United States there is currently a paucity of available real world minor rear crash data with struck vehicle delta-V, or speed change, less than or equal to 15 kilometers per hour. These data are essential as researchers attempt to define ‘whiplash’ injury risk potential in these minor crashes. This study analyzed a new set of 105 U.S. minor rear aligned crashes between passenger vehicles. Mean struck vehicle delta-V and acceleration were 6.3 km/h (s.d. = 2.1 km/h) and 1.4g (s.d. = 0.5g), respectively. A total of 113 struck vehicle occupants were diagnosed within five weeks post-crash with 761 ICD-9-CM complaints and 427 AIS injuries (99.5% AIS1) attributed to the crashes. No striking vehicle occupants reported complaints. The main ICD-9-CM diagnoses were 40.6% cervical, 22.5% lumbar/sacral and 10.2% thoracic and the main AIS1 diagnoses were 29.7% cervical, 23.2% lumbar/sacral and 14.3% thoracic. The diagnosis disparity was mainly due to coding for pre-existing degenerative diagnosis in ICD-9-CM. Degenerative spine conditions were not significant for increased AIS1 injury risk. Surprisingly, many non-‘whiplash’ diagnoses were found. The AIS injury diagnosis distribution and frequency in these minor delta-V crashes did not correspond with previous minor rear crash studies. A prospectively collected and unbiased minor rear crash databank in the model of CIREN or NASS is highly desirable to verify or refute these results for the U.S. population since the current study cohort may have been influenced by litigation. PMID:19026229

  14. Minor crashes and 'whiplash' in the United States.

    Science.gov (United States)

    Bartsch, Adam J; Gilbertson, Lars G; Prakash, Vikas; Morr, Douglas R; Wiechel, John F

    2008-10-01

    In the United States there is currently a paucity of available real world minor rear crash data with struck vehicle delta-V, or speed change, less than or equal to 15 kilometers per hour. These data are essential as researchers attempt to define 'whiplash' injury risk potential in these minor crashes. This study analyzed a new set of 105 U.S. minor rear aligned crashes between passenger vehicles. Mean struck vehicle delta-V and acceleration were 6.3 km/h (s.d. = 2.1 km/h) and 1.4 g (s.d. = 0.5 g), respectively. A total of 113 struck vehicle occupants were diagnosed within five weeks post-crash with 761 ICD-9-CM complaints and 427 AIS injuries (99.5% AIS1) attributed to the crashes. No striking vehicle occupants reported complaints. The main ICD-9-CM diagnoses were 40.6% cervical, 22.5% lumbar/sacral and 10.2% thoracic and the main AIS1 diagnoses were 29.7% cervical, 23.2% lumbar/sacral and 14.3% thoracic. The diagnosis disparity was mainly due to coding for pre-existing degenerative diagnosis in ICD-9-CM. Degenerative spine conditions were not significant for increased AIS1 injury risk. Surprisingly, many non-'whiplash' diagnoses were found. The AIS injury diagnosis distribution and frequency in these minor delta-V crashes did not correspond with previous minor rear crash studies. A prospectively collected and unbiased minor rear crash databank in the model of CIREN or NASS is highly desirable to verify or refute these results for the U.S. population since the current study cohort may have been influenced by litigation.

  15. Cell phone use while driving and attributable crash risk.

    Science.gov (United States)

    Farmer, Charles M; Braitman, Keli A; Lund, Adrian K

    2010-10-01

    Prior research has estimated that crash risk is 4 times higher when talking on a cell phone versus not talking. The objectives of this study were to estimate the extent to which drivers talk on cell phones while driving and to compute the implied annual number of crashes that could have been avoided if driver cell phone use were restricted. A national survey of approximately 1200 U.S. drivers was conducted. Respondents were asked to approximate the amount of time spent driving during a given day, number of cell phone calls made or received, and amount of driving time spent talking on a cell phone. Population attributable risk (PAR) was computed for each combination of driver gender, driver age, day of week, and time of day. These were multiplied by the corresponding crash counts to estimate the number of crashes that could have been avoided. On average, drivers were talking on cell phones approximately 7 percent of the time while driving. Rates were higher on weekdays (8%), in the afternoon and evening (8%), and for drivers younger than 30 (16%). Based on these use rates, restricting cell phones while driving could have prevented an estimated 22 percent (i.e., 1.3 million) of the crashes in 2008. Although increased rates of cell phone use while driving should be leading to increased crash rates, crash rates have been declining. Reasons for this paradox are unclear. One possibility is that the increase in cell phone use and crash risk due to cell phone use have been overestimated. Another possibility is that cell phone use has supplanted other driving distractions that were similarly hazardous.

  16. Three Cases of Spine Fractures after an Airplane Crash.

    Science.gov (United States)

    Lee, Han Joo; Moon, Bong Ju; Pennant, William A; Shin, Dong Ah; Kim, Keung Nyun; Yoon, Do Heum; Ha, Yoon

    2015-10-01

    While injuries to the spine after an airplane crash are not rare, most crashes result in fatal injuries. As such, few studies exist that reported on spine fractures sustained during airplane accidents. In this report, we demonstrate three cases of spine fractures due to crash landing of a commercial airplane. Three passengers perished from injuries after the crash landing, yet most of the passengers and crew on board survived, with injuries ranging from minor to severe. Through evaluating our three spine fracture patients, it was determined that compression fracture of the spine was the primary injury related to the airplane accident. The first patient was a 20-year-old female who sustained a T6-8 compression fracture without neurologic deterioration. The second patient was a 33-year-old female with an L2 compression fracture, and the last patient was a 49-year-old male patient with a T8 compression fracture. All three patients were managed conservatively and required spinal orthotics. During the crash, each of these patients were subjected to direct, downward high gravity z-axis (Gz) force, which gave rise to load on the spine vertically, thereby causing compression fracture. Therefore, new safety methods should be developed to prevent excessive Gz force during airplane crash landings.

  17. Fatal motorcycle crashes: a growing public health problem in Cambodia.

    Science.gov (United States)

    Roehler, Douglas R; Ear, Chariya; Parker, Erin M; Sem, Panhavuth; Ballesteros, Michael F

    2015-01-01

    This study examines the risk characteristics of fatal motorcycle crashes in Cambodia over a 5-year period (2007-2011). Secondary data analyses were conducted using the Cambodia Road Crash and Victim Information System, the only comprehensive and integrated road crash surveillance system in the country. Researchers from the Centers for Disease Control and Prevention and Handicap International found that (1) males are dying in motorcycle crashes roughly seven times more frequently than females; (2) motorcyclist fatalities increased by about 30% from 2007 to 2011; (3) the motorcyclist death rates per 100,000 population increased from 7.4 to 8.7 deaths from 2007 to 2011; and (4) speed-related crashes and not wearing motorcycle helmet were commonly reported for motorcyclist fatalities at approximately 50% and over 80% through the study years, respectively. Additionally, this study highlights that Cambodia has the highest motorcycle death rate in South-East Asia, far surpassing Thailand, Malaysia, and Myanmar. By recognising the patterns of fatal motorcycle crashes in Cambodia, local road-safety champions and stakeholders can design targeted interventions and preventative measures to improve road safety among motorcyclists.

  18. Statistical modeling of total crash frequency at highway intersections

    Directory of Open Access Journals (Sweden)

    Arash M. Roshandeh

    2016-04-01

    Full Text Available Intersection-related crashes are associated with high proportion of accidents involving drivers, occupants, pedestrians, and cyclists. In general, the purpose of intersection safety analysis is to determine the impact of safety-related variables on pedestrians, cyclists and vehicles, so as to facilitate the design of effective and efficient countermeasure strategies to improve safety at intersections. This study investigates the effects of traffic, environmental, intersection geometric and pavement-related characteristics on total crash frequencies at intersections. A random-parameter Poisson model was used with crash data from 357 signalized intersections in Chicago from 2004 to 2010. The results indicate that out of the identified factors, evening peak period traffic volume, pavement condition, and unlighted intersections have the greatest effects on crash frequencies. Overall, the results seek to suggest that, in order to improve effective highway-related safety countermeasures at intersections, significant attention must be focused on ensuring that pavements are adequately maintained and intersections should be well lighted. It needs to be mentioned that, projects could be implemented at and around the study intersections during the study period (7 years, which could affect the crash frequency over the time. This is an important variable which could be a part of the future studies to investigate the impacts of safety-related works at intersections and their marginal effects on crash frequency at signalized intersections.

  19. Three Cases of Spine Fractures after an Airplane Crash

    Science.gov (United States)

    Lee, Han Joo; Moon, Bong Ju; Pennant, William A.; Shin, Dong Ah; Kim, Keung Nyun; Yoon, Do Heum

    2015-01-01

    While injuries to the spine after an airplane crash are not rare, most crashes result in fatal injuries. As such, few studies exist that reported on spine fractures sustained during airplane accidents. In this report, we demonstrate three cases of spine fractures due to crash landing of a commercial airplane. Three passengers perished from injuries after the crash landing, yet most of the passengers and crew on board survived, with injuries ranging from minor to severe. Through evaluating our three spine fracture patients, it was determined that compression fracture of the spine was the primary injury related to the airplane accident. The first patient was a 20-year-old female who sustained a T6-8 compression fracture without neurologic deterioration. The second patient was a 33-year-old female with an L2 compression fracture, and the last patient was a 49-year-old male patient with a T8 compression fracture. All three patients were managed conservatively and required spinal orthotics. During the crash, each of these patients were subjected to direct, downward high gravity z-axis (Gz) force, which gave rise to load on the spine vertically, thereby causing compression fracture. Therefore, new safety methods should be developed to prevent excessive Gz force during airplane crash landings. PMID:27169094

  20. Aircraft Fire Protection Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Navy Aircraft Protection Laboratory provides complete test support for all Navy air vehicle fire protection systems.The facility allows for the simulation of a...

  1. Automated Inspection of Aircraft

    Science.gov (United States)

    1998-04-01

    This report summarizes the development of a robotic system designed to assist aircraft inspectors by remotely deploying non-destructive inspection (NDI) sensors and acquiring, processing, and storing inspection data. Carnegie Mellon University studie...

  2. Aircraft Depainting Technology

    National Research Council Canada - National Science Library

    Kozol, Joseph

    1999-01-01

    ... of aircraft and component stripping at various levels of maintenance. Under this program, the Navy pursued development of non-HAP chemical paint strippers as alternatives for methylene chloride based strippers...

  3. The Aircraft Industry, 2006

    National Research Council Canada - National Science Library

    Daniel, Keith

    2006-01-01

    .... and global economic growth. The overall outlook for the industry is positive. Orders for commercial aircraft are up from a boom in air travel that is likely to continue well into the next decade...

  4. The Aircraft Industry

    National Research Council Canada - National Science Library

    Fitzgerald, Tim; Baiche, Noureddine; Brewer, Mike; Collins, Al; Knapp, Kathy; Kott, Marilyn; McGill, Duncan; Mensah, Dunstan; Neighbors, Mark; Reardon, Dee

    2005-01-01

    .... As the airline companies prepare to buy new Boeing and Airbus passenger jets, they remain under intense pressure to cut costs in order to remain profitable, forcing aircraft and engine manufacturers...

  5. Essentials of aircraft armaments

    CERN Document Server

    Kaushik, Mrinal

    2017-01-01

    This book aims to provide a complete exposure about armaments from their design to launch from the combat aircraft. The book details modern ammunition and their tactical roles in warfare. The proposed book discusses aerodynamics, propulsion, structural as well as navigation, control, and guidance of aircraft armament. It also introduces the various types of ammunition developed by different countries and their changing trends. The book imparts knowledge in the field of design, and development of aircraft armaments to aerospace engineers and covers the role of the United Nations in peacekeeping and disarmament. The book will be very useful to researchers, students, and professionals working in design and manufacturing of aircraft armaments. The book will also serve air force and naval aspirants, and those interested in working on defence research and developments organizations. .

  6. Solar thermal aircraft

    Science.gov (United States)

    Bennett, Charles L.

    2007-09-18

    A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

  7. The Aircraft Morphing Program

    Science.gov (United States)

    Wlezien, R. W.; Horner, G. C.; McGowan, A. R.; Padula, S. L.; Scott, M. A.; Silcox, R. J.; Simpson, J. O.

    1998-01-01

    In the last decade smart technologies have become enablers that cut across traditional boundaries in materials science and engineering. Here we define smart to mean embedded actuation, sensing, and control logic in a tightly coupled feedback loop. While multiple successes have been achieved in the laboratory, we have yet to see the general applicability of smart devices to real aircraft systems. The NASA Aircraft Morphing program is an attempt to couple research across a wide range of disciplines to integrate smart technologies into high payoff aircraft applications. The program bridges research in seven individual disciplines and combines the effort into activities in three primary program thrusts. System studies are used to assess the highest- payoff program objectives, and specific research activities are defined to address the technologies required for development of smart aircraft systems. In this paper we address the overall program goals and programmatic structure, and discuss the challenges associated with bringing the technologies to fruition.

  8. Depreciation of aircraft

    Science.gov (United States)

    Warner, Edward P

    1922-01-01

    There is a widespread, and quite erroneous, impression to the effect that aircraft are essentially fragile and deteriorate with great rapidity when in service, so that the depreciation charges to be allowed on commercial or private operation are necessarily high.

  9. Development of a prediction model for crash occurrence by analyzing traffic crash and citation data : final report.

    Science.gov (United States)

    2017-04-30

    It is commonly acknowledged that factors such as human factors, vehicle characteristics, road design and environmental factors highly contribute to the occurrence of traffic crashes (WHO, 2004). Since human factors usually have the most significant i...

  10. Multifuel rotary aircraft engine

    Science.gov (United States)

    Jones, C.; Berkowitz, M.

    1980-01-01

    The broad objectives of this paper are the following: (1) to summarize the Curtiss-Wright design, development and field testing background in the area of rotary aircraft engines; (2) to briefly summarize past activity and update development work in the area of stratified charge rotary combustion engines; and (3) to discuss the development of a high-performance direct injected unthrottled stratified charge rotary combustion aircraft engine. Efficiency improvements through turbocharging are also discussed.

  11. 2002 Industry Studies: Aircraft

    Science.gov (United States)

    2002-01-01

    aircraft to a defense electronics, systems integration and information technology company.39 Northrop Grumman no longer seeks a position as a prime...between the military and civil market . Though also upgrading the H-1 helicopter series for the USMC, Bell has mortgaged its future on tiltrotor technology ...business in export dollars, the industry has been forced to look for new markets as worldwide aircraft sales have dropped. Because the U.S. national

  12. The analysis of the containment building for global effects of an aircraft crash

    International Nuclear Information System (INIS)

    Varpasuo, P.; Kenttaelae, J.

    1981-01-01

    The aim of the analysis was to establish the displacement and stress states for the whole building in four time points during the transient as well as determine the acceleration time histories, and acceleration response spectra for five points inside the containment building. The five points inside the containment were located between the foundation slab and the upper edge of the containment building. The total amount of nodal points in the model was 800 and the total amount of degrees of freedom was 4300; the amount of quadrilateral shell elements was 900. STARDYNE AND SAPOV programs and direct integration were used for analysis. As for the results of the analysis the following statements can be made: The results calculated by SAPIV and STARDYNE programs are essentially identical. Only the more refined LCCT-11 shell element used in STARDYNE instead of LCCT-9 element used in SAPIV causes the STARDYNE model to be more flexible and this shows in the response histories as a certain phase lag. STARDYNE response leaves gradually behind SAPIV response. The unexpected thing in acceleration responses was that the response in horizontal direction perpendicular to the load application direction was twice as large as the acceleration response in load application direction. (orig./HP)

  13. Advanced Techniques in Crash Impact Protection and Emergency Egress from Air Transport Aircraft

    Science.gov (United States)

    1976-06-01

    Lift Technology program for generating commercial transport innovation . However, the YC-15 military version with a high wing and Mach 0.75 cruise...survival technology is constantly changing as new materials, techniques, innovations , and requirements are developed. Nevertheless, the most valid data for...la Propriete Industrielle , No. 331 926, May 11, 1903. 784. Robbins, D.H., V.L Roberts, A.W. Henke, B.F. Raney, R.O. Bennett, and J.H. McElhaney

  14. Aircraft to aircraft intercomparison during SEMAPHORE

    Science.gov (United States)

    Lambert, Dominique; Durand, Pierre

    1998-10-01

    During the Structure des Echanges Mer-Atmosphère, Propriétés des Hétérogénéités Océaniques: Recherche Expérimentale (SEMAPHORE) experiment, performed in the Azores region in 1993, two French research aircraft were simultaneously used for in situ measurements in the atmospheric boundary layer. We present the results obtained from one intercomparison flight between the two aircraft. The mean parameters generally agree well, although the temperature has to be slightly shifted in order to be in agreement for the two aircraft. A detailed comparison of the turbulence parameters revealed no bias. The agreement is good for variances and is satisfactory for fluxes and skewness. A thorough study of the errors involved in flux computation revealed that the greatest accuracy is obtained for latent heat flux. Errors in sensible heat flux are considerably greater, and the worst results are obtained for momentum flux. The latter parameter, however, is more accurate than expected from previous parameterizations.

  15. Local damage to reinforced concrete structures caused by impact of aircraft engine missiles. Pt. 1

    International Nuclear Information System (INIS)

    Sugano, T.; Tsubota, H.; Kasai, Y.; Koshika, N.; Ohnuma, H.; Von Riesemann, W.A.; Bickel, D.C.; Parks, M.B.

    1993-01-01

    Structural damage induced by an aircraft crashing into a reinforced concrete structure includes local damage caused by the deformable engines, and global damage caused by the entire aircraft. Local damage to the target may consist of spalling of concrete from its front face together with missile penetration into it, scabbing of concrete from its rear face, and perforation of missile through it. Until now, local damage to concrete structures has been mainly evaluated by rigid missile impact tests. Past research work regarding local damage caused by impact of deformable missiles has been limited. This paper presents the results of a series of impact tests of small-, intermediate-, and full-scale engine models into reinforced concrete panels. The purpose of the tests was to determine the local damage to a reinforced concrete structure caused by the impact of a deformable aircraft engine. (orig.)

  16. Reducing the environmental impact of trials: a comparison of the carbon footprint of the CRASH-1 and CRASH-2 clinical trials

    Science.gov (United States)

    2011-01-01

    Background All sectors of the economy, including the health research sector, must reduce their carbon emissions. The UK National Institute for Health Research has recently prepared guidelines on how to minimize the carbon footprint of research. We compare the carbon emissions from two international clinical trials in order to identify where emissions reductions can be made. Methods We conducted a carbon audit of two clinical trials (the CRASH-1 and CRASH-2 trials), quantifying the carbon dioxide emissions produced over a one-year audit period. Carbon emissions arising from the coordination centre, freight delivery, trial-related travel and commuting were calculated and compared. Results The total emissions in carbon dioxide equivalents during the one-year audit period were 181.3 tonnes for CRASH-1 and 108.2 tonnes for CRASH-2. In total, CRASH-1 emitted 924.6 tonnes of carbon dioxide equivalents compared with 508.5 tonnes for CRASH-2. The CRASH-1 trial recruited 10,008 patients over 5.1 years, corresponding to 92 kg of carbon dioxide per randomized patient. The CRASH-2 trial recruited 20,211 patients over 4.7 years, corresponding to 25 kg of carbon dioxide per randomized patient. The largest contributor to emissions in CRASH-1 was freight delivery of trial materials (86.0 tonnes, 48% of total emissions), whereas the largest contributor in CRASH-2 was energy use by the trial coordination centre (54.6 tonnes, 30% of total emissions). Conclusions Faster patient recruitment in the CRASH-2 trial largely accounted for its greatly increased carbon efficiency in terms of emissions per randomized patient. Lighter trial materials and web-based data entry also contributed to the overall lower carbon emissions in CRASH-2 as compared to CRASH-1. Trial Registration Numbers CRASH-1: ISRCTN74459797 CRASH-2: ISRCTN86750102 PMID:21291517

  17. Reducing the environmental impact of trials: a comparison of the carbon footprint of the CRASH-1 and CRASH-2 clinical trials

    Directory of Open Access Journals (Sweden)

    Roberts Ian

    2011-02-01

    Full Text Available Abstract Background All sectors of the economy, including the health research sector, must reduce their carbon emissions. The UK National Institute for Health Research has recently prepared guidelines on how to minimize the carbon footprint of research. We compare the carbon emissions from two international clinical trials in order to identify where emissions reductions can be made. Methods We conducted a carbon audit of two clinical trials (the CRASH-1 and CRASH-2 trials, quantifying the carbon dioxide emissions produced over a one-year audit period. Carbon emissions arising from the coordination centre, freight delivery, trial-related travel and commuting were calculated and compared. Results The total emissions in carbon dioxide equivalents during the one-year audit period were 181.3 tonnes for CRASH-1 and 108.2 tonnes for CRASH-2. In total, CRASH-1 emitted 924.6 tonnes of carbon dioxide equivalents compared with 508.5 tonnes for CRASH-2. The CRASH-1 trial recruited 10,008 patients over 5.1 years, corresponding to 92 kg of carbon dioxide per randomized patient. The CRASH-2 trial recruited 20,211 patients over 4.7 years, corresponding to 25 kg of carbon dioxide per randomized patient. The largest contributor to emissions in CRASH-1 was freight delivery of trial materials (86.0 tonnes, 48% of total emissions, whereas the largest contributor in CRASH-2 was energy use by the trial coordination centre (54.6 tonnes, 30% of total emissions. Conclusions Faster patient recruitment in the CRASH-2 trial largely accounted for its greatly increased carbon efficiency in terms of emissions per randomized patient. Lighter trial materials and web-based data entry also contributed to the overall lower carbon emissions in CRASH-2 as compared to CRASH-1. Trial Registration Numbers CRASH-1: ISRCTN74459797 CRASH-2: ISRCTN86750102

  18. Creating pedestrian crash scenarios in a driving simulator environment.

    Science.gov (United States)

    Chrysler, Susan T; Ahmad, Omar; Schwarz, Chris W

    2015-01-01

    In 2012 in the United States, pedestrian injuries accounted for 3.3% of all traffic injuries but, disproportionately, pedestrian fatalities accounted for roughly 14% of traffic-related deaths (NHTSA 2014 ). In many other countries, pedestrians make up more than 50% of those injured and killed in crashes. This research project examined driver response to crash-imminent situations involving pedestrians in a high-fidelity, full-motion driving simulator. This article presents a scenario development method and discusses experimental design and control issues in conducting pedestrian crash research in a simulation environment. Driving simulators offer a safe environment in which to test driver response and offer the advantage of having virtual pedestrian models that move realistically, unlike test track studies, which by nature must use pedestrian dummies on some moving track. An analysis of pedestrian crash trajectories, speeds, roadside features, and pedestrian behavior was used to create 18 unique crash scenarios representative of the most frequent and most costly crash types. For the study reported here, we only considered scenarios where the car is traveling straight because these represent the majority of fatalities. We manipulated driver expectation of a pedestrian both by presenting intersection and mid-block crossing as well as by using features in the scene to direct the driver's visual attention toward or away from the crossing pedestrian. Three visual environments for the scenarios were used to provide a variety of roadside environments and speed: a 20-30 mph residential area, a 55 mph rural undivided highway, and a 40 mph urban area. Many variables of crash situations were considered in selecting and developing the scenarios, including vehicle and pedestrian movements; roadway and roadside features; environmental conditions; and characteristics of the pedestrian, driver, and vehicle. The driving simulator scenarios were subjected to iterative testing to

  19. 150 Passenger Commercial Aircraft

    Science.gov (United States)

    Bucovsky, Adrian; Romli, Fairuz I.; Rupp, Jessica

    2002-01-01

    It has been projected that the need for a short-range mid-sized, aircraft is increasing. The future strategy to decrease long-haul flights will increase the demand for short-haul flights. Since passengers prefer to meet their destinations quickly, airlines will increase the frequency of flights, which will reduce the passenger load on the aircraft. If a point-to-point flight is not possible, passengers will prefer only a one-stop short connecting flight to their final destination. A 150-passenger aircraft is an ideal vehicle for these situations. It is mid-sized aircraft and has a range of 3000 nautical miles. This type of aircraft would market U.S. domestic flights or inter-European flight routes. The objective of the design of the 150-passenger aircraft is to minimize fuel consumption. The configuration of the aircraft must be optimized. This aircraft must meet CO2 and NOx emissions standards with minimal acquisition price and operating costs. This report contains all the work that has been performed for the completion of the design of a 150 passenger commercial aircraft. The methodology used is the Technology Identification, Evaluation, and Selection (TIES) developed at Georgia Tech Aerospace Systems Design laboratory (ASDL). This is an eight-step conceptual design process to evaluate the probability of meeting the design constraints. This methodology also allows for the evaluation of new technologies to be implemented into the design. The TIES process begins with defining the problem with a need established and a market targeted. With the customer requirements set and the target values established, a baseline concept is created. Next, the design space is explored to determine the feasibility and viability of the baseline aircraft configuration. If the design is neither feasible nor viable, new technologies can be implemented to open up the feasible design space and allow for a plausible solution. After the new technologies are identified, they must be evaluated

  20. Crash testing of nuclear fuel shipping containers

    International Nuclear Information System (INIS)

    Jefferson, R.M.; Yoshimura, H.R.

    1977-08-01

    In an attempt to understand the dynamics of extra severe transportation accidents and to evaluate state-of-the-art computational techniques for predicting the dynamic response of shipping casks involved in vehicular system crashes, the Environmental Control Technology Division of ERDA undertook a program with Sandia to investigate these areas. The program encompasses the following distinct major efforts. The first of these utilizes computational methods for predicting the effects of the accident environment and, subsequently, to calculate the damage incurred by a container as the result of such an accident. The second phase involves the testing of 1 / 8 -scale models of transportation systems. Through the use of instrumentation and high-speed motion photography the accident environments and physical damage mechanisms are studied in detail. After correlating the results of these first two phases, a full scale event involving representative hardware is conducted. To date two of the three selected test scenarios have been completed. Results of the program to this point indicate that both computational techniques and scale modeling are viable engineering approaches to studying accident environments and physical damage to shipping casks

  1. Crash testing of nuclear fuel shipping containers

    International Nuclear Information System (INIS)

    Jefferson, R.M.; Yoshimura, H.R.

    1977-12-01

    In an attempt to understand the dynamics of extra severe transportation accidents and to evaluate state-of-the-art computational techniques for predicting the dynamic response of shipping casks involved in vehicular system crashes, the Environmental Control Technology Division of ERDA undertook a program with Sandia to investigate these areas. This program, which began in 1975, encompasses the following distinct major efforts. The first of these utilizes computational methods for predicting the effects of the accident environment and, subsequently, to calculate the damage incurred by a container as the result of such an accident. The second phase involves the testing of 1 / 8 -scale models of transportation systems. Through the use of instrumentation and high-speed motion photography, the accident environments and physical damage mechanisms are studied in detail. After correlating the results of these first two phases, a full scale event involving representative hardware is conducted. To date two of the three selected test scenarios have been completed. Results of the program to this point indicate that both computational techniques and scale modeling are viable engineering approaches to studying accident environments and physical damage to shipping casks

  2. Integrated traffic conflict model for estimating crash modification factors.

    Science.gov (United States)

    Shahdah, Usama; Saccomanno, Frank; Persaud, Bhagwant

    2014-10-01

    Crash modification factors (CMFs) for road safety treatments are usually obtained through observational models based on reported crashes. Observational Bayesian before-and-after methods have been applied to obtain more precise estimates of CMFs by accounting for the regression-to-the-mean bias inherent in naive methods. However, sufficient crash data reported over an extended period of time are needed to provide reliable estimates of treatment effects, a requirement that can be a challenge for certain types of treatment. In addition, these studies require that sites analyzed actually receive the treatment to which the CMF pertains. Another key issue with observational approaches is that they are not causal in nature, and as such, cannot provide a sound "behavioral" rationale for the treatment effect. Surrogate safety measures based on high risk vehicle interactions and traffic conflicts have been proposed to address this issue by providing a more "causal perspective" on lack of safety for different road and traffic conditions. The traffic conflict approach has been criticized, however, for lacking a formal link to observed and verified crashes, a difficulty that this paper attempts to resolve by presenting and investigating an alternative approach for estimating CMFs using simulated conflicts that are linked formally to observed crashes. The integrated CMF estimates are compared to estimates from an empirical Bayes (EB) crash-based before-and-after analysis for the same sample of treatment sites. The treatment considered involves changing left turn signal priority at Toronto signalized intersections from permissive to protected-permissive. The results are promising in that the proposed integrated method yields CMFs that closely match those obtained from the crash-based EB before-and-after analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Compulsive Cell Phone Use and History of Motor Vehicle Crash

    Science.gov (United States)

    O’Connor, Stephen S.; Whitehill, Jennifer M.; King, Kevin M.; Kernic, Mary A.; Boyle, Linda Ng; Bresnahan, Brian; Mack, Christopher D.; Ebel, Beth E.

    2013-01-01

    Introduction Few studies have examined the psychological factors underlying the association between cell phone use and motor vehicle crash. We sought to examine the factor structure and convergent validity of a measure of problematic cell phone use and explore whether compulsive cell phone use is associated with a history of motor vehicle crash. Methods We recruited a sample of 383 undergraduate college students to complete an on-line assessment that included cell phone use and driving history. We explored the dimensionality of the Cell Phone Overuse Scale (CPOS) using factor analytic methods. Ordinary least squares regression models were used to examine associations between identified subscales and measures of impulsivity, alcohol use, and anxious relationship style to establish convergent validity. We used negative binomial regression models to investigate associations between the CPOS and motor vehicle crash incidence. Results We found the CPOS to be comprised of four subscales: anticipation, activity interfering, emotional reaction, and problem recognition. Each displayed significant associations with aspects of impulsivity, problematic alcohol use, and anxious relationship style characteristics. Only the anticipation subscale demonstrated statistically significant associations with reported motor vehicle crash incidence, controlling for clinical and demographic characteristics (RR 1.13, CI 1.01 to 1.26). For each one-point increase on the 6-point anticipation subscale, risk for previous motor vehicle crash increased by 13%. Conclusions Crash risk is strongly associated with heightened anticipation about incoming phone calls or messages. The mean score on the CPOS is associated with increased risk of motor vehicle crash but does not reach statistical significance. PMID:23910571

  4. Understanding fatal older road user crash circumstances and risk factors.

    Science.gov (United States)

    Koppel, Sjaan; Bugeja, Lyndal; Smith, Daisy; Lamb, Ashne; Dwyer, Jeremy; Fitzharris, Michael; Newstead, Stuart; D'Elia, Angelo; Charlton, Judith

    2018-02-28

    This study used medicolegal data to investigate fatal older road user (ORU) crash circumstances and risk factors relating to four key components of the Safe System approach (e.g., roads and roadsides, vehicles, road users, and speeds) to identify areas of priority for targeted prevention activity. The Coroners Court of Victoria's Surveillance Database was searched to identify coronial records with at least one deceased ORU in the state of Victoria, Australia, for 2013-2014. Information relating to the ORU, crash characteristics and circumstances, and risk factors was extracted and analyzed. The average rate of fatal ORU crashes per 100,000 population was 8.1 (95% confidence interval [CI] 6.0-10.2), which was more than double the average rate of fatal middle-aged road user crashes (3.6, 95% CI 2.5-4.6). There was a significant relationship between age group and deceased road user type (χ 2 (15, N = 226) = 3.56, p road" (87.0%), on roads that were paved (94.2%), dry (74.2%), and had light traffic volume (38.3%). Road user error was identified by the police and/or coroner for the majority of fatal ORU crashes (57.9%), with a significant proportion of deceased ORU deemed to have "misjudged" (40.9%) or "failed to yield" (37.9%). Road user error was the most significant risk factor identified in fatal ORU crashes, which suggests that there is a limited capacity of the Victorian road system to fully accommodate road user errors. Initiatives related to safer roads and roadsides, vehicles, and speed zones, as well as behavioral approaches, are key areas of priority for targeted activity to prevent fatal older road user crashes in the future.

  5. Compulsive cell phone use and history of motor vehicle crash.

    Science.gov (United States)

    O'Connor, Stephen S; Whitehill, Jennifer M; King, Kevin M; Kernic, Mary A; Boyle, Linda Ng; Bresnahan, Brian W; Mack, Christopher D; Ebel, Beth E

    2013-10-01

    Few studies have examined the psychological factors underlying the association between cell phone use and motor vehicle crash. We sought to examine the factor structure and convergent validity of a measure of problematic cell phone use, and to explore whether compulsive cell phone use is associated with a history of motor vehicle crash. We recruited a sample of 383 undergraduate college students to complete an online assessment that included cell phone use and driving history. We explored the dimensionality of the Cell Phone Overuse Scale (CPOS) using factor analytic methods. Ordinary least-squares regression models were used to examine associations between identified subscales and measures of impulsivity, alcohol use, and anxious relationship style, to establish convergent validity. We used negative binomial regression models to investigate associations between the CPOS and motor vehicle crash incidence. We found the CPOS to be composed of four subscales: anticipation, activity interfering, emotional reaction, and problem recognition. Each displayed significant associations with aspects of impulsivity, problematic alcohol use, and anxious relationship style characteristics. Only the anticipation subscale demonstrated statistically significant associations with reported motor vehicle crash incidence, controlling for clinical and demographic characteristics (relative ratio, 1.13; confidence interval, 1.01-1.26). For each 1-point increase on the 6-point anticipation subscale, risk for previous motor vehicle crash increased by 13%. Crash risk is strongly associated with heightened anticipation about incoming phone calls or messages. The mean score on the CPOS is associated with increased risk of motor vehicle crash but does not reach statistical significance. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  6. Multivariate poisson lognormal modeling of crashes by type and severity on rural two lane highways.

    Science.gov (United States)

    Wang, Kai; Ivan, John N; Ravishanker, Nalini; Jackson, Eric

    2017-02-01

    In an effort to improve traffic safety, there has been considerable interest in estimating crash prediction models and identifying factors contributing to crashes. To account for crash frequency variations among crash types and severities, crash prediction models have been estimated by type and severity. The univariate crash count models have been used by researchers to estimate crashes by crash type or severity, in which the crash counts by type or severity are assumed to be independent of one another and modelled separately. When considering crash types and severities simultaneously, this may neglect the potential correlations between crash counts due to the presence of shared unobserved factors across crash types or severities for a specific roadway intersection or segment, and might lead to biased parameter estimation and reduce model accuracy. The focus on this study is to estimate crashes by both crash type and crash severity using the Integrated Nested Laplace Approximation (INLA) Multivariate Poisson Lognormal (MVPLN) model, and identify the different effects of contributing factors on different crash type and severity counts on rural two-lane highways. The INLA MVPLN model can simultaneously model crash counts by crash type and crash severity by accounting for the potential correlations among them and significantly decreases the computational time compared with a fully Bayesian fitting of the MVPLN model using Markov Chain Monte Carlo (MCMC) method. This paper describes estimation of MVPLN models for three-way stop controlled (3ST) intersections, four-way stop controlled (4ST) intersections, four-way signalized (4SG) intersections, and roadway segments on rural two-lane highways. Annual Average Daily traffic (AADT) and variables describing roadway conditions (including presence of lighting, presence of left-turn/right-turn lane, lane width and shoulder width) were used as predictors. A Univariate Poisson Lognormal (UPLN) was estimated by crash type and

  7. Aircraft accident report: NASA 712, Convair 990, N712NA, March Air Force Base, California, July 17, 1985, facts and analysis

    Science.gov (United States)

    Batthauer, Byron E.; Mccarthy, G. T.; Hannah, Michael; Hogan, Robert J.; Marlow, Frank J.; Reynard, William D.; Stoklosa, Janis H.; Yager, Thomas J.

    1986-01-01

    On July 17, l985, at 1810 P.d.t., NASA 712, a Convair 990 aircraft, was destroyed by fire at March Air Force Base, California. The fire started during the rollout after the pilot rejected the takeoff on runway 32. The rejected takeoff was initiated during the takeoff roll because of blown tires on the right landing gear. During the rollout, fragments of either the blown tires or the wheel/brake assemblies penetrated a right-wing fuel tank forward of the right main landing gear. Leaking fuel ignited while the aircraft was rolling, and fire engulfed the right wing and the fuselage after the aircraft was stopped on the runway. The 4-man flightcrew and the 15 scientists and technicians seated in the cabin evacuated the aircraft without serious injury. The fire was not extinguished by crash/rescue efforts and the aircraft was destroyed.

  8. Not just a rural occurrence: differences in agricultural equipment crash characteristics by rural-urban crash site and proximity to town.

    Science.gov (United States)

    Harland, Karisa K; Greenan, Mitchell; Ramirez, Marizen

    2014-09-01

    Although approximately one-third of agricultural equipment-related crashes occur near town, these crashes are thought to be a rural problem. This analysis examines differences between agricultural equipment-related crashes by their urban-rural distribution and distance from a town. Agricultural equipment crashes were collected from nine Midwest Departments of Transportation (2005-2008). Crash zip code was assigned as urban or rural (large, small and isolated) using Rural-Urban Commuting Areas. Crash proximity to a town was estimated with ArcGIS. Multivariable logistic regression was used to estimate the odds of crashing in an urban versus rural zip codes and across rural gradients. ANOVA analysis estimated mean distance (miles) from a crash site to a town. Over four years, 4444 crashes involved agricultural equipment. About 30% of crashes occurred in urban zip codes. Urban crashes were more likely to be non-collisions (aOR=1.69[1.24-2.30]), involve ≥2 vehicles (2 vehicles: aOR=1.58[1.14-2.20], 3+ vehicles: aOR=1.68[0.98-2.88]), occur in a town (aOR=2.06[1.73-2.45]) and within one mile of a town (aOR=1.65[1.40-1.95]) than rural crashes. The proportion of crashes within a town differed significantly across rural gradients (Purban-rural distribution (Pagricultural equipment are unexpectedly common in urban areas and near towns and cities. Education among all roadway users, increased visibility of agricultural equipment and the development of complete rural roads are needed to increase road safety and prevent agricultural equipment-related crashes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Hotspots and causes of motor vehicle crashes in Baltimore, Maryland: A geospatial analysis of five years of police crash and census data.

    Science.gov (United States)

    Dezman, Zachary; de Andrade, Luciano; Vissoci, Joao Ricardo; El-Gabri, Deena; Johnson, Abree; Hirshon, Jon Mark; Staton, Catherine A

    2016-11-01

    Road traffic injuries are a leading killer of youth (aged 15-29) and are projected to be the 7th leading cause of death by 2030. To better understand road traffic crash locations and characteristics in the city of Baltimore, we used police and census data, to describe the epidemiology, hotspots, and modifiable risk factors involved to guide further interventions. Data on all crashes in Baltimore City from 2009 to 2013 were made available from the Maryland Automated Accident Reporting System. Socioeconomic data collected by the US CENSUS 2010 were obtained. A time series analysis was conducted using an ARIMA model. We analyzed the geographical distribution of traffic crashes and hotspots using exploratory spatial data analysis and spatial autocorrelation. Spatial regression was performed to evaluate the impact of socioeconomic indicators on hotspots. In Baltimore City, between 2009 and 2013, there were a total of 100,110 crashes reported, with 1% of crashes considered severe. Of all crashes, 7% involved vulnerable road users and 12% had elderly or youth involvement. Reasons for crashes included: distracted driving (31%), speeding (6%), and alcohol or drug use (5%). After 2010, we observed an increasing trend in all crashes especially from March to June. Distracted driving then youth and elderly drivers were consistently the highest risk factors over time. Multivariate spatial regression model including socioeconomic indicators and controlling for age, gender and population size did not show a distinct predictor of crashes explaining only 20% of the road crash variability, indicating crashes are not geographically explained by socioeconomic indicators alone. In Baltimore City, road traffic crashes occurred predominantly in the high density center of the city, involved distracted driving and extremes of age with an increase in crashes from March to June. There was no association between socioeconomic variables where crashes occurred and hotspots. In depth analysis of

  10. Analysis of impact of large commercial aircraft on a prestressed containment building

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyoungsoo, E-mail: kylee@pvamu.edu [Center for Energy and Environmental Sustainability, Prairie View A and M University, Prairie view, TX, 77446 (United States); Han, Sang Eul, E-mail: hsang@inha.ac.kr [Department of Architectural Engineering, School of Architecture, Inha University, 253 Yonghyundong Nam-gu, Incheon, 402-751 (Korea, Republic of); Hong, Jung-Wuk, E-mail: j.hong@kaist.ac.kr [Department of Civil and Environmental Engineering, KAIST, 373-1 Guseon-dong, Yuseong-gu, Daejeon, 305-701 (Korea, Republic of)

    2013-12-15

    Highlights: • Aircraft impact analyses are performed using the missile–target interaction method. • A large commercial B747 aircraft is considered with erosion effect. • The rigid wall impact test shows the validity of the developed aircraft model. • The parametric studies on the fictitious containment building are performed. • The plastic failure of the target is governed by the impulse of aircraft at the first momentum peak. - Abstract: In this paper, the results of nonlinear dynamic analyses of a concrete containment building under extreme loads are presented. The impact of a large commercial B747 airliner is investigated as the extreme load, and a rigid wall impact test is performed using commercial nonlinear finite element codes. The impact forces exerted by the aircraft are verified compared with the time-dependent impact force provided by OECD/NEA (2002), which was calculated based on the so-called Riera method. The rigid wall impact analysis shows that the finite element model of a B747 is appropriate for the purpose of the aircraft crash analysis exposed to the external hazard of “Beyond Design-Basis Events” defined by U.S. Nuclear Regulatory Commission. Finally, the applicability of this methodology is further studied and verified by conducting parametric studies on the critical infrastructures of nuclear power plant containment structures.

  11. Analysis of impact of large commercial aircraft on a prestressed containment building

    International Nuclear Information System (INIS)

    Lee, Kyoungsoo; Han, Sang Eul; Hong, Jung-Wuk

    2013-01-01

    Highlights: • Aircraft impact analyses are performed using the missile–target interaction method. • A large commercial B747 aircraft is considered with erosion effect. • The rigid wall impact test shows the validity of the developed aircraft model. • The parametric studies on the fictitious containment building are performed. • The plastic failure of the target is governed by the impulse of aircraft at the first momentum peak. - Abstract: In this paper, the results of nonlinear dynamic analyses of a concrete containment building under extreme loads are presented. The impact of a large commercial B747 airliner is investigated as the extreme load, and a rigid wall impact test is performed using commercial nonlinear finite element codes. The impact forces exerted by the aircraft are verified compared with the time-dependent impact force provided by OECD/NEA (2002), which was calculated based on the so-called Riera method. The rigid wall impact analysis shows that the finite element model of a B747 is appropriate for the purpose of the aircraft crash analysis exposed to the external hazard of “Beyond Design-Basis Events” defined by U.S. Nuclear Regulatory Commission. Finally, the applicability of this methodology is further studied and verified by conducting parametric studies on the critical infrastructures of nuclear power plant containment structures

  12. Evaluation of Vehicle-Based Crash Severity Metrics.

    Science.gov (United States)

    Tsoi, Ada H; Gabler, Hampton C

    2015-01-01

    Vehicle change in velocity (delta-v) is a widely used crash severity metric used to estimate occupant injury risk. Despite its widespread use, delta-v has several limitations. Of most concern, delta-v is a vehicle-based metric which does not consider the crash pulse or the performance of occupant restraints, e.g. seatbelts and airbags. Such criticisms have prompted the search for alternative impact severity metrics based upon vehicle kinematics. The purpose of this study was to assess the ability of the occupant impact velocity (OIV), acceleration severity index (ASI), vehicle pulse index (VPI), and maximum delta-v (delta-v) to predict serious injury in real world crashes. The study was based on the analysis of event data recorders (EDRs) downloaded from the National Automotive Sampling System / Crashworthiness Data System (NASS-CDS) 2000-2013 cases. All vehicles in the sample were GM passenger cars and light trucks involved in a frontal collision. Rollover crashes were excluded. Vehicles were restricted to single-event crashes that caused an airbag deployment. All EDR data were checked for a successful, completed recording of the event and that the crash pulse was complete. The maximum abbreviated injury scale (MAIS) was used to describe occupant injury outcome. Drivers were categorized into either non-seriously injured group (MAIS2-) or seriously injured group (MAIS3+), based on the severity of any injuries to the thorax, abdomen, and spine. ASI and OIV were calculated according to the Manual for Assessing Safety Hardware. VPI was calculated according to ISO/TR 12353-3, with vehicle-specific parameters determined from U.S. New Car Assessment Program crash tests. Using binary logistic regression, the cumulative probability of injury risk was determined for each metric and assessed for statistical significance, goodness-of-fit, and prediction accuracy. The dataset included 102,744 vehicles. A Wald chi-square test showed each vehicle-based crash severity metric

  13. Potential Occupant Injury Reduction in Pre-Crash System Equipped Vehicles in the Striking Vehicle of Rear-end Crashes.

    Science.gov (United States)

    Kusano, Kristofer D; Gabler, Hampton C

    2010-01-01

    To mitigate the severity of rear-end and other collisions, Pre-Crash Systems (PCS) are being developed. These active safety systems utilize radar and/or video cameras to determine when a frontal crash, such as a front-to-back rear-end collisions, is imminent and can brake autonomously, even with no driver input. Of these PCS features, the effects of autonomous pre-crash braking are estimated. To estimate the maximum potential for injury reduction due to autonomous pre-crash braking in the striking vehicle of rear-end crashes, a methodology is presented for determining 1) the reduction in vehicle crash change in velocity (ΔV) due to PCS braking and 2) the number of injuries that could be prevented due to the reduction in collision severity. Injury reduction was only performed for belted drivers, as unbelted drivers have an unknown risk of being thrown out of position. The study was based on 1,406 rear-end striking vehicles from NASS / CDS years 1993 to 2008. PCS parameters were selected from realistic values and varied to examine the effect on system performance. PCS braking authority was varied from 0.5 G's to 0.8 G's while time to collision (TTC) was held at 0.45 seconds. TTC was then varied from 0.3 second to 0.6 seconds while braking authority was held constant at 0.6 G's. A constant braking pulse (step function) and ramp-up braking pulse were used. The study found that automated PCS braking could reduce the crash ΔV in rear-end striking vehicles by an average of 12% - 50% and avoid 0% - 14% of collisions, depending on PCS parameters. Autonomous PCS braking could potentially reduce the number of injured drivers who are belted by 19% to 57%.

  14. Systematic review of military motor vehicle crash-related injuries.

    Science.gov (United States)

    Krahl, Pamela L; Jankosky, Christopher J; Thomas, Richard J; Hooper, Tomoko I

    2010-01-01

    Motor vehicle crashes account for nearly one third of U.S. military fatalities annually. The objective of this review is to summarize the published evidence on injuries due specifically to military motor vehicle (MMV) crashes. A search of 18 electronic databases identified English language publications addressing MMV crash-related injuries between 1970 and 2006 that were available to the general public. Documents limited in distribution to military or government personnel were not evaluated. Relevant articles were categorized by study design. The search identified only 13 studies related specifically to MMV crashes. Most were case reports or case series (n=8); only one could be classified as an intervention study. Nine of the studies were based solely on data from service-specific military safety centers. Few studies exist on injuries resulting from crashes of military motor vehicles. Epidemiologic studies that assess injury rates, type, severity, and risk factors are needed, followed by studies to evaluate targeted interventions and prevention strategies. Interventions currently underway should be evaluated for effectiveness, and those proven effective in the civilian community, such as graduated driver licensing, should be considered for implementation and evaluation in military populations. Published by Elsevier Inc.

  15. Urban sprawl as a risk factor in motor vehicle crashes

    Science.gov (United States)

    Ewing, Reid; Hamidi, Shima; Grace, James B.

    2016-01-01

    A decade ago, compactness/sprawl indices were developed for metropolitan areas and counties which have been widely used in health and other research. In this study, we first update the original county index to 2010, then develop a refined index that accounts for more relevant factors, and finally seek to test the relationship between sprawl and traffic crash rates using structural equation modelling. Controlling for covariates, we find that sprawl is associated with significantly higher direct and indirect effects on fatal crash rates. The direct effect is likely due to the higher traffic speeds in sprawling areas, and the indirect effect is due to greater vehicle miles driven in such areas. Conversely, sprawl has negative direct relationships with total crashes and non-fatal injury crashes, and these offset (and sometimes overwhelm) the positive indirect effects of sprawl on both types of crashes through the mediating effect of increased vehicle miles driven. The most likely explanation is the greater prevalence of fender benders and other minor accidents in the low speed, high conflict traffic environments of compact areas, negating the lower vehicle miles travelled per capita in such areas.

  16. Human fatigue and the crash of the airship Italia

    Directory of Open Access Journals (Sweden)

    Gregg A. Bendrick

    2016-07-01

    Full Text Available The airship Italia, commanded by General Umberto Nobile, crashed during its return flight from the North Pole in 1928. The cause of the accident was never satisfactorily explained. We present evidence that the crash may have been fatigue-related. Nobile's memoirs indicate that at the time of the crash he had been awake for at least 72 h. Sleep deprivation impairs multiple aspects of cognitive functioning necessary for exploration missions. Just prior to the crash, Nobile made three command errors, all of which are of types associated with inadequate sleep. First, he ordered a release of lift gas when he should have restarted engines (an example of incorrect data synthesis, with deterioration of divergent thinking; second, he inappropriately ordered the ship above the cloud layer (a deficiency in the assessment of relative risks; and third, he remained above the cloud layer for a prolonged period of time (examples of attention to secondary problems, and calculation problems. We argue that as a result of these three errors, which would not be expected from such an experienced commander, there was no longer enough static lift to maintain level flight when the ship went below the cloud layer. Applying Circadian Performance Simulation Software to the sleep–wake patterns described by Nobile in his memoirs, we found that the predicted performance for someone awake as long as he had been is extremely low. This supports the historical evidence that human fatigue contributed to the crash of the Italia.

  17. Advanced aircraft service life monitoring method via flight-by-flight load spectra

    Science.gov (United States)

    Lee, Hongchul

    This research is an effort to understand current method and to propose an advanced method for Damage Tolerance Analysis (DTA) for the purpose of monitoring the aircraft service life. As one of tasks in the DTA, the current indirect Individual Aircraft Tracking (IAT) method for the F-16C/D Block 32 does not properly represent changes in flight usage severity affecting structural fatigue life. Therefore, an advanced aircraft service life monitoring method based on flight-by-flight load spectra is proposed and recommended for IAT program to track consumed fatigue life as an alternative to the current method which is based on the crack severity index (CSI) value. Damage Tolerance is one of aircraft design philosophies to ensure that aging aircrafts satisfy structural reliability in terms of fatigue failures throughout their service periods. IAT program, one of the most important tasks of DTA, is able to track potential structural crack growth at critical areas in the major airframe structural components of individual aircraft. The F-16C/D aircraft is equipped with a flight data recorder to monitor flight usage and provide the data to support structural load analysis. However, limited memory of flight data recorder allows user to monitor individual aircraft fatigue usage in terms of only the vertical inertia (NzW) data for calculating Crack Severity Index (CSI) value which defines the relative maneuver severity. Current IAT method for the F-16C/D Block 32 based on CSI value calculated from NzW is shown to be not accurate enough to monitor individual aircraft fatigue usage due to several problems. The proposed advanced aircraft service life monitoring method based on flight-by-flight load spectra is recommended as an improved method for the F-16C/D Block 32 aircraft. Flight-by-flight load spectra was generated from downloaded Crash Survival Flight Data Recorder (CSFDR) data by calculating loads for each time hack in selected flight data utilizing loads equations. From

  18. Aircraft gas turbines

    Energy Technology Data Exchange (ETDEWEB)

    Arai, M [Kawasaki Heavy Industries Ltd., Kobe (Japan)

    1995-03-01

    Recently the international relationship has been playing an important role in the research, development and production of the aircraft gas turbine. The YSX, which is supposed to be the 100-seat class commercial aircraft, has been planned by Japan Aircraft Development (JADC) as an international cooperative project. Recently many western aeroengine companies have offered the collaboration of small turbofan engines which would be installed on YSX to Japanese aeroengine companies (IHI, KHI and MHI). The YSX is powered by 16,000-20,000 1bs thrust class engines. As for medium turbofan engine (V2500), the V 2500 family of 22,000 to 30,000 1bs thrust has been developed since 1983 through international collaboration by seven aeroengine companies in five nations. In this paper, the recent Japan`s activities of the research, development and production with viewing the world-wide movement, are described. 6 figs.

  19. Fatal and serious road crashes involving young New Zealand drivers: a latent class clustering approach

    DEFF Research Database (Denmark)

    Weiss, Harold B.; Kaplan, Sigal; Prato, Carlo Giacomo

    2016-01-01

    , infrastructure characteristics, environmental conditions, demographic characteristics, driving behaviour, and pre-crash manoeuvres. The analysis yielded 15 and 8 latent classes of, respectively, single-vehicle and multi-vehicle crashes, and average posterior probabilities measured the odds of correct...

  20. National Motor Vehicle Crash Causation Survey (NMVCCS) - NMVCCS XML Case Viewer

    Data.gov (United States)

    Department of Transportation — The National Motor Vehicle Crash Causation Survey (NMVVCS) was a nationwide survey of crashes involving light passenger vehicles, with a focus on the factors related...

  1. New evidence concerning fatal crashes of passenger vehicles before and after adding antilock braking systems.

    Science.gov (United States)

    Farmer, C M

    2001-05-01

    Fatal crash rates for passenger cars and vans were compared for the last model year before four-wheel antilock brakes were introduced and the first model year for which antilock brakes were standard equipment. A prior study, based on fatal crash experience through 1995, reported that vehicle models with antilock brakes were more likely than identical but 1-year-earlier models to be involved in crashes fatal to their own occupants, but were less likely to be involved in crashes fatal to occupants of other vehicles. Overall, there was no significant effect of antilocks on the likelihood of fatal crashes. Similar analyses, based on fatal crash experience during 1996-98, yielded very different results. During 1996-98, vehicles with antilock brakes were again less likely than earlier models to be involved in crashes fatal to occupants of other vehicles, but they were no longer overinvolved in crashes fatal to their own occupants.

  2. Societal costs of traffic crashes and crime in Michigan : 2011 update.

    Science.gov (United States)

    2011-06-01

    "Cost estimates, including both monetary and nonmonetary quality-of-life costs specific to Michigan, were : estimated for overall traffic crashes and index crimes by experts in the field of economics of traffic crashes : and crimes. These cost estima...

  3. Feasibility of a web-based system for police crash report review and information recording.

    Science.gov (United States)

    2016-04-01

    Police crash reports include useful additional information that is not available in crash summary records. : This information may include police sketches and narratives and is often needed for detailed site-specific : safety analysis. In addition, so...

  4. Development of requirements and functional specifications for crash event data recorders : final report

    Science.gov (United States)

    2004-12-01

    The U.S. DOT has conducted research on the requirements for a Crash Event Data Recorder to facilitate the reconstruction of commercial motor vehicle crashes. This report documents the work performed on the Development of Requirements and Functiona...

  5. Correlation Analysis of Freeway Traffic Status and Crashes with Nevada Data.

    Science.gov (United States)

    2017-11-11

    This project is to study the correlation between freeway traffic status and crash risks with the historical freeway ITS data and related crash data in Nevada. With the comprehensive review of previous research results, the Center for Advanced Transpo...

  6. Taxonomy of Older Driver Behaviors and Crash Risk : with Appendices A and B

    Science.gov (United States)

    2012-02-01

    This projects objectives were to identify risky behaviors, driving habits, and exposure patterns that have been shown to increase the likelihood of crash involvement among older drivers; and to classify these crash-contributing factors according t...

  7. AIRCRAFT MAINTENANCE HANGAR

    Directory of Open Access Journals (Sweden)

    GEAMBASU Gabriel George

    2017-05-01

    Full Text Available The paper presents the maintenance process that is done on an airplane, at a certain period of time, or after a number of flight hours or cycles and describes the checks performed behind each inspection. The first part of research describes the aircraft maintenance process that has to be done after an updated maintenance manual according with aircraft type, followed by a short introduction about maintenance hangar. The second part of the paper presents a hangar design with a foldable roof and walls, which can be folded or extended, over an airplane when a maintenance process is done, or depending on weather condition.

  8. Combat aircraft noise

    Science.gov (United States)

    Sgarbozza, M.; Depitre, A.

    1992-04-01

    A discussion of the characteristics and the noise levels of combat aircraft and of a transport aircraft in taking off and landing are presented. Some methods of noise reduction are discussed, including the following: operational anti-noise procedures; and concepts of future engines (silent post-combustion and variable cycle). Some measurement results concerning the noise generated in flight at great speeds and low altitude will also be examined. Finally, the protection of the environment of French air bases against noise will be described and the possibilities of regulation examined.

  9. Glass half-full: On-road glance metrics differentiate crashes from near-crashes in the 100-Car data.

    Science.gov (United States)

    Seppelt, Bobbie D; Seaman, Sean; Lee, Joonbum; Angell, Linda S; Mehler, Bruce; Reimer, Bryan

    2017-10-01

    Much of the driver distraction and inattention work to date has focused on concerns over drivers removing their eyes from the forward roadway to perform non-driving-related tasks, and its demonstrable link to safety consequences when these glances are timed at inopportune moments. This extensive literature has established, through the analyses of glance from naturalistic datasets, a clear relationship between eyes-off-road, lead vehicle closing kinematics, and near-crash/crash involvement. This paper looks at the role of driver expectation in influencing drivers' decisions about when and for how long to remove their eyes from the forward roadway in an analysis that consider the combined role of on- and off-road glances. Using glance data collected in the 100-Car Naturalistic Driving Study (NDS), near-crashes were examined separately from crashes to examine how momentary differences in glance allocation over the 25-s prior to a precipitating event can differentiate between these two distinct outcomes. Individual glance metrics of mean single glance duration (MSGD), total glance time (TGT), and glance count for off-road and on-road glance locations were analyzed. Output from the AttenD algorithm (Kircher and Ahlström, 2009) was also analyzed as a hybrid measure; in threading together on- and off-road glances over time, its output produces a pattern of glance behavior meaningful for examining attentional effects. Individual glance metrics calculated at the epoch-level and binned by 10-s units of time across the available epoch lengths revealed that drivers in near-crashes have significantly longer on-road glances, and look less frequently between on- and off- road locations in the moments preceding a precipitating event as compared to crashes. During on-road glances, drivers in near-crashes were found to more frequently sample peripheral regions of the roadway than drivers in crashes. Output from the AttenD algorithm affirmed the cumulative net benefit of longer on

  10. Composite materials for aircraft structures

    National Research Council Canada - National Science Library

    Baker, A. A; Dutton, Stuart; Kelly, Donald

    2004-01-01

    ... materials for aircraft structures / Alan Baker, Stuart Dutton, and Donald Kelly- 2nd ed. p. cm. - (Education series) Rev. ed. of: Composite materials for aircraft structures / edited by B. C. Hos...

  11. Overreaction or Fundamentals: Some Lessons from Insiders' Response to the Market Crash of 1987.

    OpenAIRE

    Seyhun, H Nejat

    1990-01-01

    This paper shows that the 1987 crash was a surprise to corporate insiders; insiders became buyers of stock in record numbers immediately following the crash; stocks that declined more during the crash were also purchased more by insiders; and stocks that were purchased more extensively by insiders during October 1987 showed larger positive returns in 1988. The overall evidence suggests that overreaction was an important part of the crash. Copyright 1990 by American Finance Association.

  12. Association Rule Mining on Five Years of Motor Vehicle Crashes

    Directory of Open Access Journals (Sweden)

    Daher Jean Raymond

    2016-01-01

    Full Text Available Every year, road accidents kill more than a million people and injure more than 20 million worldwide. This paper aims to offer guidance on road safety and create awareness by pinpointing the major causes of traffic accidents. The study investigates motor vehicle crashes in the Genesee Finger Lakes Region of New York State. Frequency Pattern Growth algorithm is utilized to cultivate knowledge and create association rules to highlight the time and environment settings that cause the most catastrophic crashes. This knowledge can be used to warn drivers about the dangers of accidents, and how the consequences are worse given a specific context. For instance, a discovered rule from the data states that ‘most of the crashes occur between 12:00 pm and 6:00pm’; hence, it is suggested to modify existing navigation application to warn drivers about the increase in risk factor.

  13. Bayesian log-periodic model for financial crashes

    DEFF Research Database (Denmark)

    Rodríguez-Caballero, Carlos Vladimir; Knapik, Oskar

    2014-01-01

    This paper introduces a Bayesian approach in econophysics literature about financial bubbles in order to estimate the most probable time for a financial crash to occur. To this end, we propose using noninformative prior distributions to obtain posterior distributions. Since these distributions...... cannot be performed analytically, we develop a Markov Chain Monte Carlo algorithm to draw from posterior distributions. We consider three Bayesian models that involve normal and Student’s t-distributions in the disturbances and an AR(1)-GARCH(1,1) structure only within the first case. In the empirical...... part of the study, we analyze a well-known example of financial bubble – the S&P 500 1987 crash – to show the usefulness of the three methods under consideration and crashes of Merval-94, Bovespa-97, IPCMX-94, Hang Seng-97 using the simplest method. The novelty of this research is that the Bayesian...

  14. A search for gamma-ray imprints of annihilating dark matter in the galaxy, and the astrophysical implications of ultra-light fundamental vector bosons

    International Nuclear Information System (INIS)

    Zechlin, Hannes-Sebastian

    2013-12-01

    Standard Model extensions imply new elementary particles that can lead to specific astrophysical signatures. In particular, weakly interacting massive particles (WIMPs) can constitute the unknown non-luminous cold dark matter, which contributes approximately 84% to the matter content of the Universe. Annihilation or decay of WIMPs may lead to high-energy gamma-rays. In this thesis, new methods of searching for gamma-ray signals from annihilating dark matter are developed and applied. Moreover, astrophysical imprints of new ultra-light hidden U(1) gauge bosons in radio data are investigated. Hierarchical structure formation predicts a variety of smaller bound dark matter sub-halos in Milky-Way-like galactic hosts. It is shown that the Fermi-LAT is sufficiently sensitive for detecting up to a few nearby dark matter subhalos in terms of faint gamma-ray sources with a moderate angular extent. Searches in the first and second Fermi-LAT source catalogs reveal about ten candidate sources each. To discriminate the source candidates from conventional astrophysical objects, an analysis for spectral, spatial, positional, and temporal gamma-ray properties using 3.5 years of Fermi-LAT data is carried out. In addition, a multi-wavelength analysis of archival data or follow-up observations in the radio, infrared, optical, UV, X-ray, high-energy, and very-high energy gamma-ray bands is carried out. The broad-band spectra of all promising candidates are compatible with AGN, in particular high-energy peaked BL-Lac type objects (HBLs). Dark matter annihilation can contribute to the small-scale angular anisotropy spectrum of the diffuse gamma-ray background (DGB). The detection capabilities of currently operating imaging atmospheric Cherenkov telescopes and the planned Cherenkov Telescope Array (CTA) are studied. With CTA, a relative gamma-ray contribution from annihilating dark matter of 10% to the extragalactic DGB can be resolved via angular anisotropies. In terms of the dark

  15. Long Range Aircraft Trajectory Prediction

    OpenAIRE

    Magister, Tone

    2009-01-01

    The subject of the paper is the improvement of the aircraft future trajectory prediction accuracy for long-range airborne separation assurance. The strategic planning of safe aircraft flights and effective conflict avoidance tactics demand timely and accurate conflict detection based upon future four–dimensional airborne traffic situation prediction which is as accurate as each aircraft flight trajectory prediction. The improved kinematics model of aircraft relative flight considering flight ...

  16. A different perspective on conspicuity related motorcycle crashes.

    Science.gov (United States)

    de Craen, Saskia; Doumen, Michelle J A; van Norden, Yvette

    2014-02-01

    The most common type of conflict in which a motorcyclist is injured or killed is a collision between a motorcycle and a car, often in priority situations. Many studies on motorcycle safety focus on the question why car drivers fail to give priority and on the poor conspicuity of motorcycles. The concept of 'looked-but-failed-to-see' crashes is a recurring item. On the other hand, it is not entirely unexpected that motorcycles have many conflicts with cars; there simply are so many cars on the road. This paper tries to unravel whether - acknowledging the differences in exposure - car drivers indeed fail to yield for motorcycles more often than for other cars. For this purpose we compared the causes of crashes on intersections (e.g. failing to give priority, speeding, etc.) between different crash types (car-motorcycle or car-car). In addition, we compared the crash causes of dual drivers (i.e. car drivers who also have their motorcycle licence) with regular car drivers. Our crash analysis suggests that car drivers do not fail to give priority to motorcycles relatively more often than to another car when this car/motorcycle approaches from a perpendicular angle. There is only one priority situation where motorcycles seem to be at a disadvantage compared to cars. This is when a car makes a left turn, and fails to give priority to an oncoming motorcycle. This specific crash scenario occurs more often when the oncoming vehicle is a motorcycle than when it is a car. We did not find a significant difference between dual drivers and regular car drivers in how often they give priority to motorcycles compared to cars. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Large Field Photogrammetry Techniques in Aircraft and Spacecraft Impact Testing

    Science.gov (United States)

    Littell, Justin D.

    2010-01-01

    The Landing and Impact Research Facility (LandIR) at NASA Langley Research Center is a 240 ft. high A-frame structure which is used for full-scale crash testing of aircraft and rotorcraft vehicles. Because the LandIR provides a unique capability to introduce impact velocities in the forward and vertical directions, it is also serving as the facility for landing tests on full-scale and sub-scale Orion spacecraft mass simulators. Recently, a three-dimensional photogrammetry system was acquired to assist with the gathering of vehicle flight data before, throughout and after the impact. This data provides the basis for the post-test analysis and data reduction. Experimental setups for pendulum swing tests on vehicles having both forward and vertical velocities can extend to 50 x 50 x 50 foot cubes, while weather, vehicle geometry, and other constraints make each experimental setup unique to each test. This paper will discuss the specific calibration techniques for large fields of views, camera and lens selection, data processing, as well as best practice techniques learned from using the large field of view photogrammetry on a multitude of crash and landing test scenarios unique to the LandIR.

  18. INVESTIGATION OF ROADWAY GEOMETRIC AND TRAFFIC FLOW FACTORS FOR VEHICLE CRASHES USING SPATIOTEMPORAL INTERACTION

    Directory of Open Access Journals (Sweden)

    G. Gill

    2017-09-01

    Full Text Available Traffic safety is a major concern in the transportation industry due to immense monetary and emotional burden caused by crashes of various severity levels, especially the injury and fatality ones. To reduce such crashes on all public roads, the safety management processes are commonly implemented which include network screening, problem diagnosis, countermeasure identification, and project prioritization. The selection of countermeasures for potential mitigation of crashes is governed by the influential factors which impact roadway crashes. Crash prediction model is the tool widely adopted by safety practitioners or researchers to link various influential factors to crash occurrences. Many different approaches have been used in the past studies to develop better fitting models which also exhibit prediction accuracy. In this study, a crash prediction model is developed to investigate the vehicular crashes occurring at roadway segments. The spatial and temporal nature of crash data is exploited to form a spatiotemporal model which accounts for the different types of heterogeneities among crash data and geometric or traffic flow variables. This study utilizes the Poisson lognormal model with random effects, which can accommodate the yearly variations in explanatory variables and the spatial correlations among segments. The dependency of different factors linked with roadway geometric, traffic flow, and road surface type on vehicular crashes occurring at segments was established as the width of lanes, posted speed limit, nature of pavement, and AADT were found to be correlated with vehicle crashes.

  19. Analysis of factors associated with injury severity in crashes involving young New Zealand drivers

    DEFF Research Database (Denmark)

    Weiss, Harold B.; Kaplan, Sigal; Prato, Carlo Giacomo

    2014-01-01

    measures within youth-oriented road safety programs. The current study estimates discrete choice models of injury severity of crashes involving young drivers conditional on these crashes having occurred. The analysis examined a comprehensive set of single-vehicle and two-vehicle crashes involving at least...

  20. Characteristics of cyclist crashes in Italy using latent class analysis and association rule mining.

    Directory of Open Access Journals (Sweden)

    Gabriele Prati

    Full Text Available The factors associated with severity of the bicycle crashes may differ across different bicycle crash patterns. Therefore, it is important to identify distinct bicycle crash patterns with homogeneous attributes. The current study aimed at identifying subgroups of bicycle crashes in Italy and analyzing separately the different bicycle crash types. The present study focused on bicycle crashes that occurred in Italy during the period between 2011 and 2013. We analyzed categorical indicators corresponding to the characteristics of infrastructure (road type, road signage, and location type, road user (i.e., opponent vehicle and cyclist's maneuver, type of collision, age and gender of the cyclist, vehicle (type of opponent vehicle, and the environmental and time period variables (time of the day, day of the week, season, pavement condition, and weather. To identify homogenous subgroups of bicycle crashes, we used latent class analysis. Using latent class analysis, the bicycle crash data set was segmented into 19 classes, which represents 19 different bicycle crash types. Logistic regression analysis was used to identify the association between class membership and severity of the bicycle crashes. Finally, association rules were conducted for each of the latent classes to uncover the factors associated with an increased likelihood of severity. Association rules highlighted different crash characteristics associated with an increased likelihood of severity for each of the 19 bicycle crash types.

  1. Investigation of Roadway Geometric and Traffic Flow Factors for Vehicle Crashes Using Spatiotemporal Interaction

    Science.gov (United States)

    Gill, G.; Sakrani, T.; Cheng, W.; Zhou, J.

    2017-09-01

    Traffic safety is a major concern in the transportation industry due to immense monetary and emotional burden caused by crashes of various severity levels, especially the injury and fatality ones. To reduce such crashes on all public roads, the safety management processes are commonly implemented which include network screening, problem diagnosis, countermeasure identification, and project prioritization. The selection of countermeasures for potential mitigation of crashes is governed by the influential factors which impact roadway crashes. Crash prediction model is the tool widely adopted by safety practitioners or researchers to link various influential factors to crash occurrences. Many different approaches have been used in the past studies to develop better fitting models which also exhibit prediction accuracy. In this study, a crash prediction model is developed to investigate the vehicular crashes occurring at roadway segments. The spatial and temporal nature of crash data is exploited to form a spatiotemporal model which accounts for the different types of heterogeneities among crash data and geometric or traffic flow variables. This study utilizes the Poisson lognormal model with random effects, which can accommodate the yearly variations in explanatory variables and the spatial correlations among segments. The dependency of different factors linked with roadway geometric, traffic flow, and road surface type on vehicular crashes occurring at segments was established as the width of lanes, posted speed limit, nature of pavement, and AADT were found to be correlated with vehicle crashes.

  2. Fatal Cervical Spine Injury Following a Bicycle Crash

    Directory of Open Access Journals (Sweden)

    Uhrenholt Lars

    2017-06-01

    Full Text Available Spinal injury following direct loading of the head and neck is a rare sequel of bicycle crashes. Fatal head injuries following bicycle crashes have been described in great detail and safety measures such as bicycle helmets have been developed accordingly. Less frequently, however, potentially severe cervical spine injuries have been described. We present the case of a middle-aged female who sustained an ultimately fatal cervical spine injury following a collision with a car whilst biking wearing a helmet. We discuss the literature regarding the protective effects of bicycle helmets, the relevance to cervical spine injury and legislation on mandatory use of helmets for injury prevention.

  3. Biomechanical Response and Behavior of Users under Emergency Buffer Crash

    Directory of Open Access Journals (Sweden)

    R. Miralbes

    2013-01-01

    Full Text Available This paper aims to study the biomechanical effects on elevator users and the injuries sustained should an elevator crash happen. The analysis will focus on buffer impact, signaling that the earlier mentioned buffer is usually located at the bottom of the pit. In order to carry out this analysis, a numerical technique based on finite element method will be used, while elevator users will be simulated by means of automotive dummies. Two crash factors will be studied, namely, location of dummy and fall velocity. The analysis criteria will be damages sustained by the dummy, based on biomechanical index such as HIC, CSI, forces, and accelerations.

  4. Aircraft Capability Management

    Science.gov (United States)

    Mumaw, Randy; Feary, Mike

    2018-01-01

    This presentation presents an overview of work performed at NASA Ames Research Center in 2017. The work concerns the analysis of current aircraft system management displays, and the initial development of an interface for providing information about aircraft system status. The new interface proposes a shift away from current aircraft system alerting interfaces that report the status of physical components, and towards displaying the implications of degradations on mission capability. The proposed interface describes these component failures in terms of operational consequences of aircraft system degradations. The research activity was an effort to examine the utility of different representations of complex systems and operating environments to support real-time decision making of off-nominal situations. A specific focus was to develop representations that provide better integrated information to allow pilots to more easily reason about the operational consequences of the off-nominal situations. The work is also seen as a pathway to autonomy, as information is integrated and understood in a form that automated responses could be developed for the off-nominal situations in the future.

  5. Aircrafts' taxi noise emission

    NARCIS (Netherlands)

    Asensio, C.; Pagan Munoz, Raul; López, J.M.

    2008-01-01

    An investigation has been conducted, with the objective of creating a database of inputs that can be used with noise prediction software, to evaluate noise of aircraft taxing movements and community noise exposure levels. The acoustic consultant can use these data with any of the software packages,

  6. Aircraft parameter estimation

    Indian Academy of Sciences (India)

    With the evolution of high performance modern aircraft and spiraling developmental and experimental costs, the importance of flight validated databases for flight control design applications and for flight simulators has increased significantly in the recent past. Ground-based and in-flight simulators are increasingly used not ...

  7. Factors influencing pediatric Injury Severity Score and Glasgow Coma Scale in pediatric automobile crashes: results from the Crash Injury Research Engineering Network.

    Science.gov (United States)

    Ehrlich, Peter F; Brown, J Kristine; Sochor, Mark R; Wang, Stewart C; Eichelberger, Martin E

    2006-11-01

    Motor vehicle crashes account for more than 50% of pediatric injuries. Triage of pediatric patients to appropriate centers can be based on the crash/injury characteristics. Pediatric motor vehicle crash/injury characteristics can be determined from an in vitro laboratory using child crash dummies. However, to date, no detailed data with respect to outcomes and crash mechanism have been presented with a pediatric in vivo model. The Crash Injury Research Engineering Network is comprised of 10 level 1 trauma centers. Crashes were examined with regard to age, crash severity (DeltaV), crash direction, restraint use, and airbag deployment. Multiple logistic regression analysis was performed with Injury Severity Score (ISS) and Glasgow Coma Scale (GCS) as outcomes. Standard age groupings (0-4, 5-9, 10-14, and 15-18) were used. The database is biases toward a survivor population with few fatalities. Four hundred sixty-one motor vehicle crashes with 2500 injuries were analyzed (242 boys, 219 girls). Irrespective of age, DeltaV > 30 mph resulted in increased ISS and decreased GCS (eg, for 0-4 years, DeltaV 30: ISS = 19.5, GCS = 10.6; P 15) injuries than did backseat passengers (odds ratio, 1.7; 95% confidence interval, 0.7-3.4). A trend was noted for children younger than 12 years sitting in the front seat to have increased ISS and decreased GCS with airbag deployment but was limited by case number. A reproducible pattern of increased ISS and lower GCS characterized by high severity, lateral crashes in children was noted. Further analysis of the specific injuries as a function and the crash characteristic can help guide management and prevention strategies.

  8. Forensic odontological observations in the victims of DANA air crash ...

    African Journals Online (AJOL)

    Introduction: Forensic odontology or forensic dentistry is that aspect of forensic science that uses the application of dental science for the identification of unknown human remains and bite marks. Deaths resulting from mass disasters such as plane crash or fire incidence have always been given mass burial in Nigeria.

  9. Finite pressure effects on the tokamak sawtooth crash

    International Nuclear Information System (INIS)

    Nishimura, Yasutaro

    1998-07-01

    The sawtooth crash is a hazardous, disruptive phenomenon that is observed in tokamaks whenever the safety factor at the magnetic axis is below unity. Recently, Tokamak Test Fusion Reactor (TFTR) experimental data has revealed interesting features of the dynamical pressure evolution during the crash phase. Motivated by the experimental results, this dissertation focuses on theoretical modeling of the finite pressure effects on the nonlinear stage of the sawtooth crash. The crash phase has been studied numerically employed a toroidal magnetohydrodynamic (MHD) initial value code deduced from the FAR code. For the first time, by starting from a concentric equilibrium, it has been shown that the evolution through an m/n = 1/1 magnetic island induces secondary high-n ballooning instabilities. The magnetic island evolution gives rise to convection of the pressure inside the inversion radius and builds up a steep pressure gradient across the island separatrix, or current sheet, and thereby triggers ballooning instabilities below the threshold for the axisymmetric equilibrium. Due to the onset of secondary ballooning modes, concomitant fine scale vortices and magnetic stochasticity are generated. These effects produce strong flows across the current sheet, and thereby significant modify the m = 1 driven magnetic reconnection process. The resultant interaction of the high-n ballooning modes with the magnetic reconnection process is discussed

  10. STOCK MARKET CRASH AND EXPECTATIONS OF AMERICAN HOUSEHOLDS*

    Science.gov (United States)

    HUDOMIET, PÉTER; KÉZDI, GÁBOR; WILLIS, ROBERT J.

    2011-01-01

    SUMMARY This paper utilizes data on subjective probabilities to study the impact of the stock market crash of 2008 on households’ expectations about the returns on the stock market index. We use data from the Health and Retirement Study that was fielded in February 2008 through February 2009. The effect of the crash is identified from the date of the interview, which is shown to be exogenous to previous stock market expectations. We estimate the effect of the crash on the population average of expected returns, the population average of the uncertainty about returns (subjective standard deviation), and the cross-sectional heterogeneity in expected returns (disagreement). We show estimates from simple reduced-form regressions on probability answers as well as from a more structural model that focuses on the parameters of interest and separates survey noise from relevant heterogeneity. We find a temporary increase in the population average of expectations and uncertainty right after the crash. The effect on cross-sectional heterogeneity is more significant and longer lasting, which implies substantial long-term increase in disagreement. The increase in disagreement is larger among the stockholders, the more informed, and those with higher cognitive capacity, and disagreement co-moves with trading volume and volatility in the market. PMID:21547244

  11. STOCK MARKET CRASH AND EXPECTATIONS OF AMERICAN HOUSEHOLDS.

    Science.gov (United States)

    Hudomiet, Péter; Kézdi, Gábor; Willis, Robert J

    2011-01-01

    This paper utilizes data on subjective probabilities to study the impact of the stock market crash of 2008 on households' expectations about the returns on the stock market index. We use data from the Health and Retirement Study that was fielded in February 2008 through February 2009. The effect of the crash is identified from the date of the interview, which is shown to be exogenous to previous stock market expectations. We estimate the effect of the crash on the population average of expected returns, the population average of the uncertainty about returns (subjective standard deviation), and the cross-sectional heterogeneity in expected returns (disagreement). We show estimates from simple reduced-form regressions on probability answers as well as from a more structural model that focuses on the parameters of interest and separates survey noise from relevant heterogeneity. We find a temporary increase in the population average of expectations and uncertainty right after the crash. The effect on cross-sectional heterogeneity is more significant and longer lasting, which implies substantial long-term increase in disagreement. The increase in disagreement is larger among the stockholders, the more informed, and those with higher cognitive capacity, and disagreement co-moves with trading volume and volatility in the market.

  12. Nonparametric Analyses of Log-Periodic Precursors to Financial Crashes

    Science.gov (United States)

    Zhou, Wei-Xing; Sornette, Didier

    We apply two nonparametric methods to further test the hypothesis that log-periodicity characterizes the detrended price trajectory of large financial indices prior to financial crashes or strong corrections. The term "parametric" refers here to the use of the log-periodic power law formula to fit the data; in contrast, "nonparametric" refers to the use of general tools such as Fourier transform, and in the present case the Hilbert transform and the so-called (H, q)-analysis. The analysis using the (H, q)-derivative is applied to seven time series ending with the October 1987 crash, the October 1997 correction and the April 2000 crash of the Dow Jones Industrial Average (DJIA), the Standard & Poor 500 and Nasdaq indices. The Hilbert transform is applied to two detrended price time series in terms of the ln(tc-t) variable, where tc is the time of the crash. Taking all results together, we find strong evidence for a universal fundamental log-frequency f=1.02±0.05 corresponding to the scaling ratio λ=2.67±0.12. These values are in very good agreement with those obtained in earlier works with different parametric techniques. This note is extracted from a long unpublished report with 58 figures available at , which extensively describes the evidence we have accumulated on these seven time series, in particular by presenting all relevant details so that the reader can judge for himself or herself the validity and robustness of the results.

  13. The cost of crashes in South Africa 2016

    CSIR Research Space (South Africa)

    Labuschagne, F

    2017-07-01

    Full Text Available to eradicate poverty and grow the economy. The previous Road Traffic Crashes (RTCs) cost estimation was published in 2004 by the Department of Transport (DoT). Though it was useful for benefit/cost evaluation of road safety programmes and projects targeting...

  14. Patterns of Injuries After Road Traffic Crashes Involving Bodabodas

    African Journals Online (AJOL)

    2010-01-12

    Jan 12, 2010 ... Globally, trauma resulting from road traffic crashes is a major cause of death and disability with majority occur- ... Bodabodas are a major form of transport in the city of. Kampala and in other towns in East Africa. .... Injury Control Injury Surveillance Reports (2000 – 2003). Injury Control Centre, Kampala. 4.

  15. Exploring older driver crash trend: New Jersey case study

    Directory of Open Access Journals (Sweden)

    Vanvi Trieu

    2014-04-01

    Full Text Available Older drivers age 65 and above are known to experience greater risk on the roadway as well as increasing the risk to other roadway users. Within the next 20 years, their population is expected to increase from 41 million in 2011 to 70 million in 2030. To address this foreseeable change, the nation's recent Moving Ahead for Progress in the 21st Century (MAP-21 act requires state and local governments to examine older drivers and pedestrian risks and implement countermeasures as appropriate. This research was conducted to assist agencies in strategising for future plans, programmes and initiatives to better address the problem presented. This was accomplished by performing a detailed engineering analysis on crash data of older drivers over a 10-year period (2003–2012 from the state of New Jersey to identify crash trends and characteristics. A major finding from this research was the increase in fatal crashes of older drivers as a function of age. Top-ranking collision types with other vehicles and non-vehicles were identified. Crashes as a function of seasonal change, climate and lighting conditions were also examined.

  16. A mathematical definition of the financial bubbles and crashes

    Science.gov (United States)

    Watanabe, Kota; Takayasu, Hideki; Takayasu, Misako

    2007-09-01

    We check the validity of the mathematical method of detecting financial bubbles or crashes, which is based on a data fitting with an exponential function. We show that the period of a bubble can be determined nearly uniquely independent of the precision of data. The method is widely applicable for stock market data such as the Internet bubble.

  17. Real time control of restraint systems in frontal crashes

    NARCIS (Netherlands)

    Griotto, G.; Lemmen, P.P.M.; Eijnden, E.A.C. van den; Leijsen, A.C.P. van; Schie, C. van; Cooper, J.

    2007-01-01

    It is generally accepted that the targets for fatality reduction in car accidents set by Governments in Europe, USA and Japan can only be met by using advanced technologies that will include a broad range of sensors to monitor the crash likelihood and severity, vehicle condition, occupant type and

  18. Mass casualty triage after an airplane crash near Amsterdam

    NARCIS (Netherlands)

    Postma, Ingri L. E.; Weel, Hanneke; Heetveld, Martin J.; van der Zande, Ineke; Bijlsma, Taco S.; Bloemers, Frank W.; Goslings, J. Carel

    2013-01-01

    Triage is an important aspect of the management of mass casualty incidents. This study describes the triage after the Turkish Airlines Crash near Amsterdam in 2009. The results of the triage and the injuries of P3 casualties were evaluated. In addition, the role of the trauma mechanism and its

  19. High-frequency Trading, Algorithmic Finance, and the Flash Crash

    DEFF Research Database (Denmark)

    Borch, Christian

    2016-01-01

    The Flash Crash of 6 May 2010 has an interesting status in discussions of high-frequency trading, i.e. fully automated, superfast computerized trading: it is invoked both as an important illustration of how this field of algorithmic trading operates and, more often, as an example of how fully aut...... about resonance in quantitative finance....

  20. Feedback control of occupant motion during a crash

    NARCIS (Netherlands)

    Hesseling, R.J.; Steinbuch, M.; Veldpaus, F.E.; Klisch, T.

    2006-01-01

    Passive in-vehicle safety systems such as the air bag and the belt restrain the occupant during a crash. However, often their behavior is not optimal in terms of occupant injuries. This paper discusses an approach to design an ideal restraint system. The problem is formulated as a feedback tracking

  1. U.S. Civil Air Show Crashes, 1993 to 2013: Burden, Fatal Risk Factors, and Evaluation of a Risk Index for Aviation Crashes.

    Science.gov (United States)

    Ballard, Sarah-Blythe; Osorio, Victor B

    2015-01-01

    This study provides new public health data about U.S. civil air shows. Risk factors for fatalities in civil air show crashes were analyzed. The value of the FIA score in predicting fatal outcomes was evaluated. With the use of the FAA's General Aviation and Air Taxi Survey and the National Transportation Safety Board's data, the incidence of civil air show crashes from 1993 to 2013 was calculated. Fatality risk factors for crashes were analyzed by means of regression methods. The FIA index was validated to predict fatal outcomes by using the factors of fire, instrument conditions, and away-from-airport location, and was evaluated through receiver operating characteristic (ROC) curves. The civil air show crash rate was 31 crashes per 1,000 civil air events. Of the 174 civil air show crashes that occurred during the study period, 91 (52%) involved at least one fatality; on average, 1.1 people died per fatal crash. Fatalities were associated with four major risk factors: fire [adjusted odds ratio (AOR) = 7.1, 95% confidence interval (CI) = 2.4 to 20.6, P Civil air show crashes were marked by a high risk of fatal outcomes to pilots in aerobatic performances but rare mass casualties. The FIA score was not a valid measurement of fatal risk in civil air show crashes.

  2. Narrative text analysis to identify technologies to prevent motor vehicle crashes: examples from military vehicles.

    Science.gov (United States)

    Pollack, Keshia M; Yee, Nathan; Canham-Chervak, Michelle; Rossen, Lauren; Bachynski, Kathleen E; Baker, Susan P

    2013-02-01

    The purpose of this research is to describe the leading circumstances of military vehicle crashes to guide prioritization and implementation of crash avoidance and/or warning technologies. A descriptive study using narrative text analysis on 3,944 military vehicle crash narratives. Crash data on drivers, from 2001 to 2006, were assembled from the U.S. Army Combat Readiness/Safety Center. Reviewers collected information on the circumstances of crashes and determined if vehicle technology could have prevented the crash. Nearly 98% of the crashes were nonfatal; 63% occurred in the U.S. and 24% in Iraq. Among crash events where the direction of the impact was recorded, 32% were to the front of the vehicle and 16% involved a vehicle being rear-ended. Rollovers were mentioned in 20% of the narratives. Technology was determined to have the potential to prevent 26% of the crashes, with the forward collision warning system, rear end collision avoidance, emergency brake assistance, and rollover stability control system likely to have the greatest impacts. Some technologies available for civilian vehicles may prevent certain military crash circumstances. The results of this research are significant in light of ongoing global military operations that rely on military vehicles. Improving the preventive technology featured on military vehicles may be an effective strategy to reduce the occurrence of military crashes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Increased inequality in mortality from road crashes among Arabs and Jews in Israel.

    Science.gov (United States)

    Magid, Avi; Leibovitch-Zur, Shalhevet; Baron-Epel, Orna

    2015-01-01

    Previous studies in several countries have shown that the economically disadvantaged seem to have a greater risk of being involved in a car crash. The aim of the present study was to compare rates and trends in mortality and injury from road crashes by age among the Arab and Jewish populations in Israel. Data on road crashes with casualties (2003-2011) from the Israeli Central Bureau of Statistics were analyzed. Age-adjusted road crash injury rates and mortality rates for 2003 to 2011 were calculated and time trends for each age group and population group are presented. Time trend significance was evaluated by linear regression models. Arabs in Israel are at increased risk of injury and mortality from road crashes compared to Jews. Road crash injury rates have significantly decreased in both populations over the last decade, although the rates have been persistently higher among Arabs. Road crash mortality rates have also decreased significantly in the Jewish population but not in the Arab population. This implies an increase in the disparity in mortality between Jews and Arabs. The most prominent differences in road crash injury and mortality rates between Arabs and Jews can be observed in young adults and young children. The reduction in road crashes in the last decade is a positive achievement. However, the reductions are not equal among Arabs and Jews in Israel. Therefore, an increase in the disparities in mortality from road crashes is apparent. Public health efforts need to focus specifically on decreasing road crashes in the Arab community.

  4. COMPARISON OF SEVERITY AFFECTING FACTORS BETWEEN YOUNG AND OLDER DRIVERS INVOLVED IN SINGLE VEHICLE CRASHES

    Directory of Open Access Journals (Sweden)

    Sunanda DISSANAYAKE, Ph.D., P.E.

    2004-01-01

    Full Text Available Single vehicle crashes contribute to a significant amount of fatalities in the United States. At the same time, fatality crash involvement rates of young and older drivers are well above the average and both groups are identified as critical groups when it comes to highway safety. Therefore, the study described in this paper developed separate models to predict crash severity of single vehicle crashes by young and older drivers. By using the models, factors affecting towards increased crash severity were identified for each group and comparisons were made. Almost all the common identified factors influenced both driver groups in the same manner except in the case of alcohol and drug usage, which indicated an interesting finding in the case of crash severity of older drivers. Speeding and non-usage of a restraint device were the two most important factors affecting towards increased crash severity for both driver groups at all severity levels. Additionally, ejection and existence of curve/grade were determinants of higher young driver crash severity at all levels. For older drivers, having a frontal impact point was a severity determinant at all levels. County of residence and weather condition were not effective in making any changes with respect to crash severity at any level, while some other factors had a minimal affect. Findings of this study are beneficial in investigating the potential ways of reducing crash severity, which could also be influential in reducing the occurrence of crashes as well.

  5. Characteristics of Single Vehicle Crashes with a Teen Driver in South Carolina, 2005-2008.

    Science.gov (United States)

    Shults, Ruth A; Bergen, Gwen; Smith, Tracy J; Cook, Larry; Kindelberger, John; West, Bethany

    2017-09-22

    Teens' crash risk is highest in the first years of independent driving. Circumstances surrounding fatal crashes have been widely documented, but less is known about factors related to nonfatal teen driver crashes. This study describes single vehicle nonfatal crashes involving the youngest teen drivers (15-17 years), compares these crashes to single vehicle nonfatal crashes among adult drivers (35-44 years) and examines factors related to nonfatal injury producing crashes for teen drivers. Police crash data linked to hospital inpatient and emergency department data for 2005-2008 from the South Carolina Crash Outcomes Data Evaluation System (CODES) were analyzed. Nonfatal, single vehicle crashes involving passenger vehicles occurring on public roadways for teen (15-17 years) drivers were compared with those for adult (35-44 years) drivers on temporal patterns and crash risk factors per licensed driver and per vehicle miles traveled. Vehicle miles traveled by age group was estimated using data from the 2009 National Household Travel Survey. Multivariable log-linear regression analysis was conducted for teen driver crashes to determine which characteristics were related to crashes resulting in a minor/moderate injury or serious injury to at least one vehicle occupant. Compared with adult drivers, teen drivers in South Carolina had 2.5 times the single vehicle nonfatal crash rate per licensed driver and 11 times the rate per vehicle mile traveled. Teen drivers were nearly twice as likely to be speeding at the time of the crash compared with adult drivers. Teen driver crashes per licensed driver were highest during the afternoon hours of 3:00-5:59 pm and crashes per mile driven were highest during the nighttime hours of 9:00-11:59 pm. In 66% of the teen driver crashes, the driver was the only occupant. Crashes were twice as likely to result in serious injury when teen passengers were present than when the teen driver was alone. When teen drivers crashed while

  6. Aircraft engines. IV

    Energy Technology Data Exchange (ETDEWEB)

    Ruffles, P C

    1989-01-01

    Configurational design and thermodynamic performance gain trends are projected into the next 50 years, in view of the growing interest of aircraft manufacturers in both larger and more efficient high-bypass turbofan engines for subsonic flight and variable cycle engines for supersonic flight. Ceramic- and metal-matrix composites are envisioned as the key to achievement of turbine inlet temperatures 300 C higher than the 1400 C which is characteristic of the state-of-the-art, with the requisite high stiffness, strength, and low density. Such fiber-reinforced materials can be readily tailored to furnish greatest strength in a specific direction of loading. Large, low-density engines are critical elements of future 1000-seat aircraft.

  7. Aircraft engine pollution reduction.

    Science.gov (United States)

    Rudey, R. A.

    1972-01-01

    The effect of engine operation on the types and levels of the major aircraft engine pollutants is described and the major factors governing the formation of these pollutants during the burning of hydrocarbon fuel are discussed. Methods which are being explored to reduce these pollutants are discussed and their application to several experimental research programs are pointed out. Results showing significant reductions in the levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen obtained from experimental combustion research programs are presented and discussed to point out potential application to aircraft engines. An experimental program designed to develop and demonstrate these and other advanced, low pollution combustor design methods is described. Results that have been obtained to date indicate considerable promise for reducing advanced engine exhaust pollutants to levels significantly below current engines.

  8. Aircraft Design Software

    Science.gov (United States)

    1997-01-01

    Successful commercialization of the AirCraft SYNThesis (ACSYNT) tool has resulted in the creation of Phoenix Integration, Inc. ACSYNT has been exclusively licensed to the company, an outcome of a seven year, $3 million effort to provide unique software technology to a focused design engineering market. Ames Research Center formulated ACSYNT and in working with the Virginia Polytechnic Institute CAD Laboratory, began to design and code a computer-aided design for ACSYNT. Using a Joint Sponsored Research Agreement, Ames formed an industry-government-university alliance to improve and foster research and development for the software. As a result of the ACSYNT Institute, the software is becoming a predominant tool for aircraft conceptual design. ACSYNT has been successfully applied to high- speed civil transport configuration, subsonic transports, and supersonic fighters.

  9. Activity modes selection for project crashing through deterministic simulation

    Directory of Open Access Journals (Sweden)

    Ashok Mohanty

    2011-12-01

    Full Text Available Purpose: The time-cost trade-off problem addressed by CPM-based analytical approaches, assume unlimited resources and the existence of a continuous time-cost function. However, given the discrete nature of most resources, the activities can often be crashed only stepwise. Activity crashing for discrete time-cost function is also known as the activity modes selection problem in the project management. This problem is known to be NP-hard. Sophisticated optimization techniques such as Dynamic Programming, Integer Programming, Genetic Algorithm, Ant Colony Optimization have been used for finding efficient solution to activity modes selection problem. The paper presents a simple method that can provide efficient solution to activity modes selection problem for project crashing.Design/methodology/approach: Simulation based method implemented on electronic spreadsheet to determine activity modes for project crashing. The method is illustrated with the help of an example.Findings: The paper shows that a simple approach based on simple heuristic and deterministic simulation can give good result comparable to sophisticated optimization techniques.Research limitations/implications: The simulation based crashing method presented in this paper is developed to return satisfactory solutions but not necessarily an optimal solution.Practical implications: The use of spreadsheets for solving the Management Science and Operations Research problems make the techniques more accessible to practitioners. Spreadsheets provide a natural interface for model building, are easy to use in terms of inputs, solutions and report generation, and allow users to perform what-if analysis.Originality/value: The paper presents the application of simulation implemented on a spreadsheet to determine efficient solution to discrete time cost tradeoff problem.

  10. The risk of groundling fatalities from unintentional airplane crashes.

    Science.gov (United States)

    Thompson, K M; Rabouw, R F; Cooke, R M

    2001-12-01

    The crashes of four hijacked commercial planes on September 11, 2001, and the repeated televised images of the consequent collapse of the World Trade Center and one side of the Pentagon will inevitably change people's perceptions of the mortality risks to people on the ground from crashing airplanes. Goldstein and colleagues were the first to quantify the risk for Americans of being killed on the ground from a crashing airplane for unintentional events, providing average point estimates of 6 in a hundred million for annual risk and 4.2 in a million for lifetime risk. They noted that the lifetime risk result exceeded the commonly used risk management threshold of 1 in a million, and suggested that the risk to "groundlings" could be a useful risk communication tool because (a) it is a man-made risk (b) arising from economic activities (c) from which the victims derive no benefit and (d) exposure to which the victims cannot control. Their results have been used in risk communication. This analysis provides updated estimates of groundling fatality risks from unintentional crashes using more recent data and a geographical information system approach to modeling the population around airports. The results suggest that the average annual risk is now 1.2 in a hundred million and the lifetime risk is now 9 in ten million (below the risk management threshold). Analysis of the variability and uncertainty of this estimate, however, suggests that the exposure to groundling fatality risk varies by about a factor of approximately 100 in the spatial dimension of distance to an airport, with the risk declining rapidly outside the first 2 miles around an airport. We believe that the risk to groundlings from crashing airplanes is more useful in the context of risk communication when information about variability and uncertainty in the risk estimates is characterized, but we suspect that recent events will alter its utility in risk communication.

  11. Combat Aircraft Maneuverability.

    Science.gov (United States)

    1981-12-01

    rodynamique, propulsion, rdsistance den structures, etc ... - lea m~thodes d’essaia an soufflerie, aur banca au aol, sur simulateurs. A un niveau de synthbse...Dunstan Graham, "Aircraft Dynamics and Automatic Control," Princeton University Press , Princeton, N.J., 1973. 9. Hoh, Roger H., Thomas T. Myers...discussion of the roll coupling problem" Progress in Aerospace Sciences, Vol 15, Pergamon Press , Oxford 1974 17-8 (6] R.W. KLOPPENSTEIN "Zeroes of

  12. The effects of age, gender, and crash types on drivers' injury-related health care costs.

    Science.gov (United States)

    Shen, Sijun; Neyens, David M

    2015-04-01

    There are many studies that evaluate the effects of age, gender, and crash types on crash related injury severity. However, few studies investigate the effects of those crash factors on the crash related health care costs for drivers that are transported to hospital. The purpose of this study is to examine the relationships between drivers' age, gender, and the crash types, as well as other crash characteristics (e.g., not wearing a seatbelt, weather condition, and fatigued driving), on the crash related health care costs. The South Carolina Crash Outcome Data Evaluation System (SC CODES) from 2005 to 2007 was used to construct six separate hierarchical linear regression models based on drivers' age and gender. The results suggest that older drivers have higher health care costs than younger drivers and male drivers tend to have higher health care costs than female drivers in the same age group. Overall, single vehicle crashes had the highest health care costs for all drivers. For males older than 64-years old sideswipe crashes are as costly as single vehicle crashes. In general, not wearing a seatbelt, airbag deployment, and speeding were found to be associated with higher health care costs. Distraction-related crashes are more likely to be associated with lower health care costs in most cases. Furthermore this study highlights the value of considering drivers in subgroups, as some factors have different effects on health care costs in different driver groups. Developing an understanding of longer term outcomes of crashes and their characteristics can lead to improvements in vehicle technology, educational materials, and interventions to reduce crash-related health care costs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Aircraft gas turbines

    Energy Technology Data Exchange (ETDEWEB)

    Sekido, T [Ishikawajima-Harima Heavy Industries, Co. Ltd., Tokyo (Japan)

    1994-03-01

    Current developmental activities of aircraft gas turbines in Japan are reviewed. V2500-A5 engine with thrust of 30,000 LBF is scheduled to be used for real aircraft in 1994, and intensive developmental activities are also proceeding in larger engines over 90,000 LBF. Recently, developmental programs of engines for 75-100 seat aircraft have been actively discussed, and Japanese engine makers are having discussions towards international collaboration. Such engines will be high bypass turbofans of 12,000-22,000 LBF. Development of SST/HST engines in a speed range from subsonic to Mach 5 is under the initiative of the Agency of Industrial Science and Technology. The Technical Research and Development Institute of Japan, Defence Agency achieved the target thrust of 3.4 tons in the small turbofan engine program, and the small turboshaft engine for small helicopters is also under development. Both National Aerospace Laboratory (NAL) and Institute of Space and Aeronautical Science (ISAS) are now conducting the research programs on turbo-ramjet engines under a component test phase. 1 fig.

  14. SELF-REPORTED DIFFERENCES BETWEEN CRASH-INVOLVED AND NON-CRASH-INVOLVED THREE-WHEELER DRIVERS IN SRI LANKA

    Directory of Open Access Journals (Sweden)

    A.K. SOMASUNDARASWARAN, Dr.

    2006-01-01

    Full Text Available Despite being an important mode of transportation in the developing world, little research has been conducted to understand the factors contributing to crashes involving three wheel vehicles. This study surveyed a convenient sample of 505 professional three-wheeler drivers in Sri Lanka to explore the similarities and differences in the demographic and work characteristics between three-wheeler drivers who reported experiencing at least one collision in the past twelve months and those who reported that they were not involved in any collisions. Our study revealed some interesting results that were quite different from those obtained in the studies on professional drivers in developed countries. In particular, both drivers with less than one year and more than five years of driving experience in our study were found to be associated with higher probability of crash involvement. Also, the number of trips per day and the average travel distance per trip were found to be insignificant in delineating between crash-involved and non-crash-involved drivers. Moreover, crash-involved drivers, on average, have significantly fewer working days per week and fewer hours per day, suggesting that the conventional approach used in most developed countries to tackle fatigue among professional drivers do not appear to be suitable for solving the road safety problem involving three-wheeler drivers in a developing country. Also, since the age of most drivers falls in a narrow range, this U-shaped relationship is not likely to be a result of youth and ageing but of inexperience in newer drivers and complacency in more experienced drivers. Lastly, since a relatively large proportion of the drivers had driven without a valid driving license, legislation and enforcement interventions are likely to be less effective than education and engineering countermeasures.

  15. Perseus A High Altitude Remotely Piloted Aircraft being Towed in Flight

    Science.gov (United States)

    1994-01-01

    Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially developed as part of NASA's Small High-Altitude Science Aircraft (SHASA) program, which later evolved into the ERAST project. The Perseus Proof-Of-Concept aircraft first flew in November 1991 and made three low-altitude flights within a month to validate the Perseus aerodynamic model and flight control systems. Next came the redesigned Perseus A, which incorporated a closed-cycle combustion system that mixed oxygen carried aboard the aircraft with engine exhaust to compensate for the thin air at high altitudes. The Perseus A was towed into the air by a ground vehicle and its engine started after it became airborne. Prior to landing, the engine was stopped, the propeller locked in horizontal position, and the Perseus A glided to a landing on its unique bicycle-type landing gear. Two Perseus A aircraft were built and made 21 flights in 1993-1994. One of the Perseus A aircraft reached over 50,000 feet in altitude on its third test flight. Although one of the Perseus A aircraft was destroyed in a crash after a vertical gyroscope failed in flight, the other aircraft completed its test program and remains on display at Aurora's facility in Manassas. Perseus B first flew Oct. 7, 1994, and made two flights in 1996 before being damaged in a hard landing on the dry lakebed after a propeller shaft failure. After a number of improvements and upgrades-including extending the original 58.5-foot wingspan to 71.5 feet to enhance high-altitude performance--the Perseus B returned to Dryden in the spring of 1998 for a series of four flights. Thereafter, a series of modifications were made including external fuel pods on the wing that more than doubled the fuel capacity to 100 gallons. Engine power was increased by more than 20 percent by boosting the turbocharger output. Fuel consumption was reduced with fuel control modifications and a leaner fuel-air mixture that did not compromise power. The

  16. Principles for Aircraft Energy Mapping

    OpenAIRE

    Berg, Frederick T N

    2013-01-01

    An increasing emphasis on energy eciency in aircraft systems has in recentyears led to greater interest in integrated design and optimisation withinthe industry. New tools are needed to understand, compare and manage energyuse of an aircraft throughout its design and operation. This thesis describes a new methodology to meet this need: aircraft exergy mapping.The choice of exergy, a 2nd law metric, to describe the energy ows is fundamental to the methodology, providing numerous advantages ove...

  17. Social costs of road crashes: An international analysis.

    Science.gov (United States)

    Wijnen, Wim; Stipdonk, Henk

    2016-09-01

    This paper provides an international overview of the most recent estimates of the social costs of road crashes: total costs, value per casualty and breakdown in cost components. The analysis is based on publications about the national costs of road crashes of 17 countries, of which ten high income countries (HICs) and seven low and middle income countries (LMICs). Costs are expressed as a proportion of the gross domestic product (GDP). Differences between countries are described and explained. These are partly a consequence of differences in the road safety level, but there are also methodological explanations. Countries may or may not correct for underreporting of road crashes, they may or may not use the internationally recommended willingness to pay (WTP)-method for estimating human costs, and there are methodological differences regarding the calculation of some other cost components. The analysis shows that the social costs of road crashes in HICs range from 0.5% to 6.0% of the GDP with an average of 2.7%. Excluding countries that do not use a WTP- method for estimating human costs and countries that do not correct for underreporting, results in average costs of 3.3% of GDP. For LMICs that do correct for underreporting the share in GDP ranges from 1.1% to 2.9%. However, none of the LMICs included has performed a WTP study of the human costs. A major part of the costs is related to injuries: an average share of 50% for both HICs and LMICs. The average share of fatalities in the costs is 23% and 30% respectively. Prevention of injuries is thus important to bring down the socio-economic burden of road crashes. The paper shows that there are methodological differences between countries regarding cost components that are taken into account and regarding the methods used to estimate specific cost components. In order to be able to make sound comparisons of the costs of road crashes across countries, (further) harmonization of cost studies is recommended. This can be

  18. A search for gamma-ray imprints of annihilating dark matter in the galaxy, and the astrophysical implications of ultra-light fundamental vector bosons

    Energy Technology Data Exchange (ETDEWEB)

    Zechlin, Hannes-Sebastian

    2013-12-15

    Standard Model extensions imply new elementary particles that can lead to specific astrophysical signatures. In particular, weakly interacting massive particles (WIMPs) can constitute the unknown non-luminous cold dark matter, which contributes approximately 84% to the matter content of the Universe. Annihilation or decay of WIMPs may lead to high-energy gamma-rays. In this thesis, new methods of searching for gamma-ray signals from annihilating dark matter are developed and applied. Moreover, astrophysical imprints of new ultra-light hidden U(1) gauge bosons in radio data are investigated. Hierarchical structure formation predicts a variety of smaller bound dark matter sub-halos in Milky-Way-like galactic hosts. It is shown that the Fermi-LAT is sufficiently sensitive for detecting up to a few nearby dark matter subhalos in terms of faint gamma-ray sources with a moderate angular extent. Searches in the first and second Fermi-LAT source catalogs reveal about ten candidate sources each. To discriminate the source candidates from conventional astrophysical objects, an analysis for spectral, spatial, positional, and temporal gamma-ray properties using 3.5 years of Fermi-LAT data is carried out. In addition, a multi-wavelength analysis of archival data or follow-up observations in the radio, infrared, optical, UV, X-ray, high-energy, and very-high energy gamma-ray bands is carried out. The broad-band spectra of all promising candidates are compatible with AGN, in particular high-energy peaked BL-Lac type objects (HBLs). Dark matter annihilation can contribute to the small-scale angular anisotropy spectrum of the diffuse gamma-ray background (DGB). The detection capabilities of currently operating imaging atmospheric Cherenkov telescopes and the planned Cherenkov Telescope Array (CTA) are studied. With CTA, a relative gamma-ray contribution from annihilating dark matter of 10% to the extragalactic DGB can be resolved via angular anisotropies. In terms of the dark

  19. Assessing the role of pavement macrotexture in preventing crashes on highways.

    Science.gov (United States)

    Pulugurtha, Srinivas S; Kusam, Prasanna R; Patel, Kuvleshay J

    2010-02-01

    The objective of this article is to assess the role of pavement macrotexture in preventing crashes on highways in the State of North Carolina. Laser profilometer data obtained from the North Carolina Department of Transportation (NCDOT) for highways comprising four corridors are processed to calculate pavement macrotexture at 100-m (approximately 330-ft) sections according to the American Society for Testing and Materials (ASTM) standards. Crash data collected over the same lengths of the corridors were integrated with the calculated pavement macrotexture for each section. Scatterplots were generated to assess the role of pavement macrotexture on crashes and logarithm of crashes. Regression analyses were conducted by considering predictor variables such as million vehicle miles of travel (as a function of traffic volume and length), the number of interchanges, the number of at-grade intersections, the number of grade-separated interchanges, and the number of bridges, culverts, and overhead signs along with pavement macrotexture to study the statistical significance of relationship between pavement macrotexture and crashes (both linear and log-linear) when compared to other predictor variables. Scatterplots and regression analysis conducted indicate a more statistically significant relationship between pavement macrotexture and logarithm of crashes than between pavement macrotexture and crashes. The coefficient for pavement macrotexture, in general, is negative, indicating that the number of crashes or logarithm of crashes decreases as it increases. The relation between pavement macrotexture and logarithm of crashes is generally stronger than between most other predictor variables and crashes or logarithm of crashes. Based on results obtained, it can be concluded that maintaining pavement macrotexture greater than or equal to 1.524 mm (0.06 in.) as a threshold limit would possibly reduce crashes and provide safe transportation to road users on highways.

  20. Comparison of four statistical and machine learning methods for crash severity prediction.

    Science.gov (United States)

    Iranitalab, Amirfarrokh; Khattak, Aemal

    2017-11-01

    Crash severity prediction models enable different agencies to predict the severity of a reported crash with unknown severity or the severity of crashes that may be expected to occur sometime in the future. This paper had three main objectives: comparison of the performance of four statistical and machine learning methods including Multinomial Logit (MNL), Nearest Neighbor Classification (NNC), Support Vector Machines (SVM) and Random Forests (RF), in predicting traffic crash severity; developing a crash costs-based approach for comparison of crash severity prediction methods; and investigating the effects of data clustering methods comprising K-means Clustering (KC) and Latent Class Clustering (LCC), on the performance of crash severity prediction models. The 2012-2015 reported crash data from Nebraska, United States was obtained and two-vehicle crashes were extracted as the analysis data. The dataset was split into training/estimation (2012-2014) and validation (2015) subsets. The four prediction methods were trained/estimated using the training/estimation dataset and the correct prediction rates for each crash severity level, overall correct prediction rate and a proposed crash costs-based accuracy measure were obtained for the validation dataset. The correct prediction rates and the proposed approach showed NNC had the best prediction performance in overall and in more severe crashes. RF and SVM had the next two sufficient performances and MNL was the weakest method. Data clustering did not affect the prediction results of SVM, but KC improved the prediction performance of MNL, NNC and RF, while LCC caused improvement in MNL and RF but weakened the performance of NNC. Overall correct prediction rate had almost the exact opposite results compared to the proposed approach, showing that neglecting the crash costs can lead to misjudgment in choosing the right prediction method. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Investigation of time and weather effects on crash types using full Bayesian multivariate Poisson lognormal models.

    Science.gov (United States)

    El-Basyouny, Karim; Barua, Sudip; Islam, Md Tazul

    2014-12-01

    Previous research shows that various weather elements have significant effects on crash occurrence and risk; however, little is known about how these elements affect different crash types. Consequently, this study investigates the impact of weather elements and sudden extreme snow or rain weather changes on crash type. Multivariate models were used for seven crash types using five years of daily weather and crash data collected for the entire City of Edmonton. In addition, the yearly trend and random variation of parameters across the years were analyzed by using four different modeling formulations. The proposed models were estimated in a full Bayesian context via Markov Chain Monte Carlo simulation. The multivariate Poisson lognormal model with yearly varying coefficients provided the best fit for the data according to Deviance Information Criteria. Overall, results showed that temperature and snowfall were statistically significant with intuitive signs (crashes decrease with increasing temperature; crashes increase as snowfall intensity increases) for all crash types, while rainfall was mostly insignificant. Previous snow showed mixed results, being statistically significant and positively related to certain crash types, while negatively related or insignificant in other cases. Maximum wind gust speed was found mostly insignificant with a few exceptions that were positively related to crash type. Major snow or rain events following a dry weather condition were highly significant and positively related to three crash types: Follow-Too-Close, Stop-Sign-Violation, and Ran-Off-Road crashes. The day-of-the-week dummy variables were statistically significant, indicating a possible weekly variation in exposure. Transportation authorities might use the above results to improve road safety by providing drivers with information regarding the risk of certain crash types for a particular weather condition. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. An Undergraduate Student Instrumentation Project (USIP) to Develop New Instrument Technology to Study the Auroral Ionosphere and Stratospheric Ozone Layer Using Ultralight Balloon Payloads

    Science.gov (United States)

    Nowling, M.; Ahmad, H.; Gamblin, R.; Guala, D.; Hermosillo, D.; Pina, M.; Marrero, E.; Canales, D. R. J.; Cao, J.; Ehteshami, A.; Bering, E. A., III; Lefer, B. L.; Dunbar, B.; Bias, C.; Shahid, S.

    2015-12-01

    This project is currently engaging twelve undergraduate students in the process of developing new technology and instrumentation for use in balloon borne geospace investigations in the auroral zone. Motivation stems from advances in microelectronics and consumer electronic technology. Given the technological innovations over the past 20 years it now possible to develop new instrumentation to study the auroral ionosphere and stratospheric ozone layer using ultralight balloon payloads for less than 6lbs and $3K per payload. The University of Houston Undergraduate Student Instrumentation Project (USIP) team has built ten such payloads for launch using 1500 gm latex weather balloons deployed in Houston, TX, Fairbanks, AK, and as well as zero pressure balloons launched from northern Sweden. The latex balloon project will collect vertical profiles of wind velocity, temperature, electrical conductivity, ozone, and odd nitrogen. This instrument payload will also produce profiles of pressure, electric field, and air-earth electric current. The zero pressure balloons will obtain a suite of geophysical measurements including: DC electric field, electric field and magnetic flux, optical imaging, total electron content of ionosphere via dual-channel GPS, X-ray detection, and infrared/UV spectroscopy. Students flew payloads with different combinations of these instruments to determine which packages are successful. Data collected by these instruments will be useful in understanding the nature of electrodynamic coupling in the upper atmosphere and how the global earth system is changing. Twelve out of the launched fifteen payloads were successfully launched and recovered. Results and best practices learned from lab tests and initial Houston test flights will be discussed.

  3. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Manufacture of new aircraft, aircraft... Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b) and (c) of this section, no person may manufacture a new aircraft, aircraft engine, or propeller based on...

  4. Analysing the Severity and Frequency of Traffic Crashes in Riyadh City Using Statistical Models

    Directory of Open Access Journals (Sweden)

    Saleh Altwaijri

    2012-12-01

    Full Text Available Traffic crashes in Riyadh city cause losses in the form of deaths, injuries and property damages, in addition to the pain and social tragedy affecting families of the victims. In 2005, there were a total of 47,341 injury traffic crashes occurred in Riyadh city (19% of the total KSA crashes and 9% of those crashes were severe. Road safety in Riyadh city may have been adversely affected by: high car ownership, migration of people to Riyadh city, high daily trips reached about 6 million, high rate of income, low-cost of petrol, drivers from different nationalities, young drivers and tremendous growth in population which creates a high level of mobility and transport activities in the city. The primary objective of this paper is therefore to explore factors affecting the severity and frequency of road crashes in Riyadh city using appropriate statistical models aiming to establish effective safety policies ready to be implemented to reduce the severity and frequency of road crashes in Riyadh city. Crash data for Riyadh city were collected from the Higher Commission for the Development of Riyadh (HCDR for a period of five years from 1425H to 1429H (roughly corresponding to 2004-2008. Crash data were classified into three categories: fatal, serious-injury and slight-injury. Two nominal response models have been developed: a standard multinomial logit model (MNL and a mixed logit model to injury-related crash data. Due to a severe underreporting problem on the slight injury crashes binary and mixed binary logistic regression models were also estimated for two categories of severity: fatal and serious crashes. For frequency, two count models such as Negative Binomial (NB models were employed and the unit of analysis was 168 HAIs (wards in Riyadh city. Ward-level crash data are disaggregated by severity of the crash (such as fatal and serious injury crashes. The results from both multinomial and binary response models are found to be fairly consistent but

  5. Chemistry in aircraft plumes

    Energy Technology Data Exchange (ETDEWEB)

    Kraabol, A.G.; Stordal, F.; Knudsen, S. [Norwegian Inst. for Air Research, Kjeller (Norway); Konopka, P. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Wessling (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    An expanding plume model with chemistry has been used to study the chemical conversion of NO{sub x} to reservoir species in aircraft plumes. The heterogeneous conversion of N{sub 2}O{sub 5} to HNO{sub 3}(s) has been investigated when the emissions take place during night-time. The plume from an B747 has been simulated. During a ten-hour calculation the most important reservoir species was HNO{sub 3} for emissions at noon. The heterogeneous reactions had little impact on the chemical loss of NO{sub x} to reservoir species for emissions at night. (author) 4 refs.

  6. Chemistry in aircraft plumes

    Energy Technology Data Exchange (ETDEWEB)

    Kraabol, A G; Stordal, F; Knudsen, S [Norwegian Inst. for Air Research, Kjeller (Norway); Konopka, P [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Wessling (Germany). Inst. fuer Physik der Atmosphaere

    1998-12-31

    An expanding plume model with chemistry has been used to study the chemical conversion of NO{sub x} to reservoir species in aircraft plumes. The heterogeneous conversion of N{sub 2}O{sub 5} to HNO{sub 3}(s) has been investigated when the emissions take place during night-time. The plume from an B747 has been simulated. During a ten-hour calculation the most important reservoir species was HNO{sub 3} for emissions at noon. The heterogeneous reactions had little impact on the chemical loss of NO{sub x} to reservoir species for emissions at night. (author) 4 refs.

  7. Commercial Aircraft Protection

    Energy Technology Data Exchange (ETDEWEB)

    Ehst, David A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-10-26

    This report summarizes the results of theoretical research performed during 3 years of P371 Project implementation. In results of such research a new scientific conceptual technology of quasi-passive individual infrared protection of heat-generating objects – Spatial Displacement of Thermal Image (SDTI technology) was developed. Theoretical substantiation and description of working processes of civil aircraft individual IR-protection system were conducted. The mathematical models and methodology were presented, there were obtained the analytical dependencies which allow performing theoretical research of the affect of intentionally arranged dynamic field of the artificial thermal interferences with variable contrast onto main parameters of optic-electronic tracking and homing systems.

  8. Sir Hugh Cairns: The neurosurgeon who introduced crash helmets

    Directory of Open Access Journals (Sweden)

    Shahsivadhanan Sundaravadhanan

    2017-01-01

    Full Text Available Statistics prove that more Indians die in Road traffic related accidents than in wars. Prior to World War II, the death toll across the world used to be very high. It was at this juncture that a Military Neurosurgeon named Hugh Cairns introduced the compulsory wearing of crash helmets and brought about a reduction in mortality by more than 50%. Within a decade of introduction of crash helmets in Britain, the entire world followed suit. The results of his efforts are here for all of us to see. This innovative military neurosurgeon is credited as the one who introduced the concept of mobile neurosurgical units during world war and also the first proponent of usage of penicillin in war. His concepts in war surgery are still followed by militaries across the world. This article comes as a tribute to this great Neurosurgeon who helped in saving millions of lives.

  9. Response of equipment in nuclear power plants to airplane crash

    International Nuclear Information System (INIS)

    Schalk, M.; Woelfel, H.

    1975-01-01

    The question has been posed concerning the effect of airplane crash on the safety of the equipment (pipes, vessels, etc.) mounted on the floors and walls inside the outer structure. This equipment is set into vibration by the crash-induced shaking of the outer building; the resulting stresses may be quite appreciable. The following questions arise: a) how large are these stresses. Can they, for example, be larger than the stresses produced by earthquake loading. b) What are the significant response parameters. c) Which methods of analysis and design criteria are reasonable. To what extent is it possible to apply the techniques which have become generally accepted for earthquake loading. The paper presents a preliminary answer to these questions pending further work in this area. (orig./HP) [de

  10. Thermal characterization of QSH crashes in RFX-mod

    Science.gov (United States)

    Fassina, Alessandro; Gobbin, Marco; Franz, Paolo; Marrelli, Lionello; Ruzzon, Alberto

    2012-10-01

    QSH (Quasi Single Helicity) states have gained a growing interest in RFP research since they show improved confinement and transport features with respect to standard discharges. However, ITBs associated with QSH states can be obtained only in a transient way, and in general with a shorter lifetime with respect to that of the QSH phase [1]. In this work the analysis has essentially the purpose of confirming, with TS data, the Te dynamics seen with the double filter, multichord SXR spectrometer in [1]: TS data allow a better spatial definition of temperature profile and a more reliable description of plasma edge. Te profile features in rising and crashing phases are determined via ensemble averaging, possible precursors of thermal crashes are identified, while q(r) behavior is studied identifying the thermal structures associated with rational surfaces. [4pt] [1] Ruzzon et al, 39th EPS Conference, P2.023

  11. Relationship of Worldwide Rocket Launch Crashes with Geophysical Parameters

    Directory of Open Access Journals (Sweden)

    N. Romanova

    2013-01-01

    Full Text Available A statistical comparison of launch crashes at different worldwide space ports with geophysical factors has been performed. A comprehensive database has been compiled, which includes 50 years of information from the beginning of the space age in 1957 about launch crashes occurring world-wide. Special attention has been paid to statistics concerning launches at the largest space ports: Plesetsk, Baikonur, Cape Canaveral, and Vandenberg. In search of a possible influence of geophysical factors on launch failures, such parameters as the vehicle type, local time, season, sunspot number, high-energy electron fluxes, and solar proton events have been examined. Also, we have analyzed correlations with the geomagnetic indices as indirect indicators of the space weather condition. Regularities found in this study suggest that further detailed studies of space weather effects on launcher systems, especially in the high-latitude regions, should be performed.

  12. Identifying the Bottom Line after a Stock Market Crash

    Science.gov (United States)

    Roehner, B. M.

    In this empirical paper we show that in the months following a crash there is a distinct connection between the fall of stock prices and the increase in the range of interest rates for a sample of bonds. This variable, which is often referred to as the interest rate spread variable, can be considered as a statistical measure for the disparity in lenders' opinions about the future; in other words, it provides an operational definition of the uncertainty faced by economic agents. The observation that there is a strong negative correlation between stock prices and the spread variable relies on the examination of eight major crashes in the United States between 1857 and 1987. That relationship which has remained valid for one and a half century in spite of important changes in the organization of financial markets can be of interest in the perspective of Monte Carlo simulations of stock markets.

  13. Simulations of Laboratory Astrophysics Experiments using the CRASH code

    Science.gov (United States)

    Trantham, Matthew; Kuranz, Carolyn; Fein, Jeff; Wan, Willow; Young, Rachel; Keiter, Paul; Drake, R. Paul

    2015-11-01

    Computer simulations can assist in the design and analysis of laboratory astrophysics experiments. The Center for Radiative Shock Hydrodynamics (CRASH) at the University of Michigan developed a code that has been used to design and analyze high-energy-density experiments on OMEGA, NIF, and other large laser facilities. This Eulerian code uses block-adaptive mesh refinement (AMR) with implicit multigroup radiation transport, electron heat conduction and laser ray tracing. This poster will demonstrate some of the experiments the CRASH code has helped design or analyze including: Kelvin-Helmholtz, Rayleigh-Taylor, magnetized flows, jets, and laser-produced plasmas. This work is funded by the following grants: DEFC52-08NA28616, DE-NA0001840, and DE-NA0002032.

  14. Evaluating the police service quality for handling traffic crash reporting

    DEFF Research Database (Denmark)

    Janstrup, Kira Hyldekær; Kaplan, Sigal; Barfod, Michael Bruhn

    2017-01-01

    at the police service quality for handling the reporting of traffic crashes. Design/methodology/approach This study introduces a novel approach to evaluate service quality that combines multi-criteria decision analysis (MCDA) with latent class analysis (LCA). Moreover, this study presents the design of a web....../value This study advances the knowledge about police service quality with a novel expert-based decision support tool based on SERVQUAL, MCDA and LCA, demonstrates its applicability in countries with a high-police service, and opportunities and barriers for increasing the crash reporting rate....... participated in the survey that yielded 86 complete responses. Findings The novel approach was successfully applied and its implementation demonstrated the usefulness of the tool even in countries with a high police service. Results showed that the participating stakeholders perceived human factors as more...

  15. Response of equipment in nuclear power plants to airplane crash

    International Nuclear Information System (INIS)

    Schalk, M.; Woelfel, H.

    1976-01-01

    Nuclear power plants in Germany are to be designed against airplane crash. Two problems arise: first, the local problem of penetration as well as local destruction of the building and secondly the airplane induced vibrations of the whole building which cause loadings for secondary systems (equipment). This paper deals especially with the second problem. Floor response spectra due to airplane crash are presented for two different power plant buildings. The influence of various parameters (time history of excitation, direction and location of impact, mathematical model, soil, damping, etc.) are discussed. A comparison with the results of earthquake loading is given. Suggestions are made for developing suitable floor design spectra and using them to analyse multidegree-of-freedom systems. However, the paper gives only a partial answer to the questions arising because of some important restrictions which had to be made. Studies concerning these restrictions are still being conducted and will be presented in a separate paper. (Auth.)

  16. Plane down in the city: Operation Crash and Surge.

    Science.gov (United States)

    Kann, Duane F; Draper, Thomas W

    2014-01-01

    This article is about the experiences gained from the largest full-scale exercise ever conducted in the State of Florida, specifically regarding the Orlando International Airport (MCO) venues. The exercise was centred on an airplane crashing into a hotel just outside of MCO property. The scenario clarified details regarding Incident Command and the unique jurisdictional responsibilities associated with a large-scale mass casualty incident. There were additional challenges with airline operations, walking wounded, and information sharing that provided valuable experiences toward enhancing emergency operations. This article also outlines information gained by the MCO "go team" that traveled to San Francisco following the crash of Asiana flight 214. This real-life incident shone a light on many of the strengths and opportunities found throughout the MCO exercise and this article shows the interrelationship of both of these invaluable experiences.

  17. Aircraft vulnerability analysis by modelling and simulation

    CSIR Research Space (South Africa)

    Willers, CJ

    2014-09-01

    Full Text Available attributable to misuse of the weapon or to missile performance restrictions. This paper analyses some of the factors affecting aircraft vulnerability and demonstrates a structured analysis of the risk and aircraft vulnerability problem. The aircraft...

  18. Topological data analysis of financial time series: Landscapes of crashes

    Science.gov (United States)

    Gidea, Marian; Katz, Yuri

    2018-02-01

    We explore the evolution of daily returns of four major US stock market indices during the technology crash of 2000, and the financial crisis of 2007-2009. Our methodology is based on topological data analysis (TDA). We use persistence homology to detect and quantify topological patterns that appear in multidimensional time series. Using a sliding window, we extract time-dependent point cloud data sets, to which we associate a topological space. We detect transient loops that appear in this space, and we measure their persistence. This is encoded in real-valued functions referred to as a 'persistence landscapes'. We quantify the temporal changes in persistence landscapes via their Lp-norms. We test this procedure on multidimensional time series generated by various non-linear and non-equilibrium models. We find that, in the vicinity of financial meltdowns, the Lp-norms exhibit strong growth prior to the primary peak, which ascends during a crash. Remarkably, the average spectral density at low frequencies of the time series of Lp-norms of the persistence landscapes demonstrates a strong rising trend for 250 trading days prior to either dotcom crash on 03/10/2000, or to the Lehman bankruptcy on 09/15/2008. Our study suggests that TDA provides a new type of econometric analysis, which complements the standard statistical measures. The method can be used to detect early warning signals of imminent market crashes. We believe that this approach can be used beyond the analysis of financial time series presented here.

  19. Can a stochastic cusp catastrophe model explain stock market crashes?

    Czech Academy of Sciences Publication Activity Database

    Baruník, Jozef; Vošvrda, Miloslav

    2009-01-01

    Roč. 33, č. 10 (2009), s. 1824-1836 ISSN 0165-1889 R&D Projects: GA ČR GD402/09/H045; GA ČR GA402/09/0965 Grant - others:GAUK(CZ) 46108 Institutional research plan: CEZ:AV0Z10750506 Keywords : Stochastic cusp catastrophe * Bifurcations * Singularity * Nonlinear dynamics * Stock market crash Subject RIV: AH - Economics Impact factor: 1.097, year: 2009

  20. Post-Crash Neoliberalism in Theory and Practice

    OpenAIRE

    Whitham, Ben

    2017-01-01

    The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link. Despite the massive state interventions into financial markets following the crash of 2007, the academic literature on the political-economic theory and practice of neoliberalism – a phenomenon often (mis)identified as equivalent to ‘free market’ fundamentalism or a second wave of laissez-faire – has continued to flourish, rather than decline i...