Science.gov

Sample records for gnss-based positioning attacks

  1. GNSS-based network positioning technology for cooperative emergency management

    NASA Astrophysics Data System (ADS)

    Wu, Caicong; Chu, Tianxing; Tang, Anning; Su, Huaihong

    2009-06-01

    Personal digital assistant (PDA) with built-in GPS chip begins to be used for city management and emergency response management nowadays. The intelligent terminal can be used for event recording, multimedia (photo, audio, and video) capturing, wireless communication, GPS positioning and navigation. In the near future, PDA would take place of the vehicle GPS monitoring terminal to provide more functions and convenient. This article organizes the PDA of the same team for emergency response event into an integrated network through wireless communication so that each terminal can see each other on the map, including the vehicle GPS monitoring terminals. All of the terminals should send its GPS position and collected information to the emergency response center (ERC) through GPRS with a customized protocol. Then the center would create the socket connection to push the neighbors' location and common or special information to the others in the team according to the terminal's requirement and its authorities, and the leader or commander could send commands and messages to all of the underling members also. The GNSS based positioning and communication network organizes the dispersive emergency response personnel handheld with PDA and vehicles equipped with vehicle GPS monitoring terminal into an organic and cooperative network, each member in the network can see where its colleagues are, so as to seek for the help or support and exchange information in real time without calling which avoids exposure to the tracked objects. The Compass-1 satellite positioning and communication terminal is also used for personnel and vehicle positioning and message reporting. Altay is selected as the demonstration area. The prototype emergency management system is established for the local public security bureau and well validates the terminals and network function.

  2. The Value of Positioning Integrity for GNSS-Based Electronic Fee Collection Systems

    NASA Astrophysics Data System (ADS)

    Gomes, P.; Barradas Pereira, R.

    2007-08-01

    The main objective for a GNSS-based Electronic Fee Collection systems is to obtain its PVT with a certain level of quality, expressed in terms of accuracy, integrity, continuity and availability. The ability to provide efficient toll collect is directly related with availability of integrity at the On-Board Unit. Assuming EGNOS assures a service with a certain defined quality, these systems should take advantage from such assurance. The integrity of posit ioning refers to the assurance that the system works within specified limits. These limits relate to the maximum error that the system can cope while continuing to exhibit a correct behaviour. For tolling this translates to maximum error that is allowed while identifying the correct charge objects.

  3. Ionospheric Challenges for GNSS Based Augmentation Systems

    NASA Astrophysics Data System (ADS)

    Doherty, P.; Valladares, C. E.

    2007-12-01

    The ionosphere is a highly dynamic physical phenomenon that presents a variable source of error for Global Navigation Satellite System (GNSS) signals and GNSS based operational systems. The Federal Aviation Administration's (FAA) Wide-Area Augmentation System (WAAS) was designed to enhance the GNSS standard positioning service by providing additional accuracy, availability and integrity that is sufficient for use in commercial aviation. It is the first of a number of planned regional Satellite Based Augmentation Systems (SBAS). Other systems in development include the European EGNOS system, the MSAS system in Japan and the GAGAN system in India. In addition, the South American countries are investigating the feasibility of operating an SBAS system in this region. Much of the WAAS ionospheric research and development focused on defining and mitigating ionospheric challenges characteristic of the mid-latitude regions, where the ionosphere is well studied and relatively quiescent. The EGNOS and MSAS systems will primarily operate under a similarly quiescent mid-latitude ionosphere. SBAS system development in South America, India and other low-latitude regions, however, will have to contend with much more extreme conditions. These conditions include strong spatial and temporal gradients, plasma depletions and scintillation. All of these conditions have a potential to limit SBAS performance in the low latitude regions. This presentation will review the effects that the ionosphere has on the mid-latitude WAAS system. It will present the techniques that are used to mitigate ionospheric disturbances induced on the system during severe geomagnetic activity and it will quantify the effect that this activity has on system performance. The presentation will then present data from the South American Low-latitude Ionospheric Sensor Network (LISN) that can be used to infer the ionospheric effects on SBAS performance in the most challenging low-latitude ionospheric environment

  4. Localization of an air target by means of GNSS-based multistatic radar

    NASA Astrophysics Data System (ADS)

    Akhmedov, Daulet Sh.; Raskaliyev, Almat S.

    2016-08-01

    The possibility of utilizing transmitters of opportunity for target detection, tracking and positioning is of great interest to the radar community. In particular the optional use of Global Navigation Satellite System (GNSS) has lately triggered scientific research that has purpose to take advantage of this source of signal generation for passive radar. Number of studies have been conducted previously on development of GNSS-based bistatic and multistatic radars for detection and range estimation to the object located in the close atmosphere. To further enrich research in this area, we present a novel method for coordinate determination of the air target by means of the GNSS-based multistatic radar.

  5. Quantum position verification in bounded-attack-frequency model

    NASA Astrophysics Data System (ADS)

    Gao, Fei; Liu, Bin; Wen, QiaoYan

    2016-11-01

    In 2011, Buhrman et al. proved that it is impossible to design an unconditionally secure quantum position verification (QPV) protocol if the adversaries are allowed to previously share unlimited entanglements. Afterwards, people started to design secure QPV protocols in practical settings, e.g. the bounded-storage model, where the adversaries' pre-shared entangled resources are supposed to be limited. Here we focus on another practical factor that it is very difficult for the adversaries to perform attack operations with unlimitedly high frequency. Concretely, we present a new kind of QPV protocols, called non-simultaneous QPV. And we prove the security of a specific non-simultaneous QPV protocol with the assumption that the frequency of the adversaries' attack operations is bounded, but no assumptions on their pre-shared entanglements or quantum storage. Actually, in our nonsimultaneous protocol, the information whether there comes a signal at present time is also a piece of command. It renders the adversaries "blind", that is, they have to execute attack operations with unlimitedly high frequency no matter whether a signal arrives, which implies the non-simultaneous QPV is also secure in the bounded-storage model.

  6. GNSS-based densification of the ITRF velocity field through a collaborative approach

    NASA Astrophysics Data System (ADS)

    Legrand, Juliette; Bruyninx, Carine; Craymer, Michael; Dawson, John; Griffiths, Jake; Kenyeres, Ambrus; Rebischung, Paul; Sánchez, Laura; Santamaría-Gómez, Alvaro; Saria, Elifuraha; Altamimi, Zuheir

    2015-04-01

    The objective of the IAG Working Group "Integration of Dense Velocity Fields in the ITRF" is to provide a GNSS-based dense, unified and reliable velocity field globally referenced in the ITRF (International Terrestrial Reference Frame) and useful for geodynamical and geophysical interpretations. The WG is embedded in IAG Sub-Commission 1.3 "Regional Reference Frames" where it coexists with the Regional Reference Frame Sub-Commissions AFREF (Africa), APREF (Asia & Pacific), EUREF (Europe), NAREF (North America), SCAR (Antarctica), SIRGAS (Latin America & Caribbean). These IAG Regional Reference Frame sub-commissions are responsible for providing GNSS-based densified weekly solutions for their region. To obtain such a densified velocity field, the WG combined the individual weekly solutions from 7 individual contributors (AFREF, APREF, EUREF, NAREF (NGS, GSB), SIRGAS, IGS) and then stacked these weekly combined solutions in order to derive a ITRF2008 densification as well as the associated residual position time series for more than 2800 sites. Here we present the latest densification results.

  7. Implementation of Positive Operator-Valued Measure in Passive Faraday Mirror Attack

    NASA Astrophysics Data System (ADS)

    Wang, Wei-Long; Gao, Ming; Ma, Zhi

    2015-03-01

    Passive Faraday-mirror (PFM) attack is based on imperfect Faraday mirrors in practical quantum cryptography systems and a set of three-dimensional Positive Operator-Valued Measure (POVM) operators plays an important role in this attack. In this paper, we propose a simple scheme to implement the POVM in PFM attack on an Faraday-Michelson quantum cryptography system. Since the POVM can not be implemented directly with previous methods, in this scheme it needs to expand the states sent by Alice and the POVM operators in the attack into four-dimensional Hilbert space first, without changing the attacking effect by calculation. Based on the methods proposed by Ahnert and Payne, the linear-optical setup for implementing the POVM operators is derived. At last, the complete setup for realizing the PFM attack is presented with all parameters. Furthermore, our scheme can also be applied to realize PFM attack on a plug-and-play system by changing the parameters in the setup. Supported by National Natural Science Foundation of China under Grant Nos. 61472446, U1204602, and National High Technology Research and Development Program of China under Grant No. 2011AA010803, and the Open Project Program of the State Key Laboratory of Mathematical Engineering and Advanced Computing under Grant No. 2013A14

  8. Foveal and peripheral fields of vision influences perceptual skill in anticipating opponents' attacking position in volleyball.

    PubMed

    Schorer, Jörg; Rienhoff, Rebecca; Fischer, Lennart; Baker, Joseph

    2013-09-01

    The importance of perceptual-cognitive expertise in sport has been repeatedly demonstrated. In this study we examined the role of different sources of visual information (i.e., foveal versus peripheral) in anticipating volleyball attack positions. Expert (n = 11), advanced (n = 13) and novice (n = 16) players completed an anticipation task that involved predicting the location of volleyball attacks. Video clips of volleyball attacks (n = 72) were spatially and temporally occluded to provide varying amounts of information to the participant. In addition, participants viewed the attacks under three visual conditions: full vision, foveal vision only, and peripheral vision only. Analysis of variance revealed significant between group differences in prediction accuracy with higher skilled players performing better than lower skilled players. Additionally, we found significant differences between temporal and spatial occlusion conditions. Both of those factors interacted separately, but not combined with expertise. Importantly, for experts the sum of both fields of vision was superior to either source in isolation. Our results suggest different sources of visual information work collectively to facilitate expert anticipation in time-constrained sports and reinforce the complexity of expert perception.

  9. The GNSS-based component for the new Indonesian tsunami early warning centre provided by GITEWS

    NASA Astrophysics Data System (ADS)

    Falck, C.; Ramatschi, M.; Bartsch, M.; Merx, A.; Hoeberechts, J.; Rothacher, M.

    2009-04-01

    Introduction Nowadays GNSS technologies are used for a large variety of precise positioning applications. The accuracy can reach the mm level depending on the data analysis methods. GNSS technologies thus offer a high potential to support tsunami early warning systems, e.g., by detection of ground motions due to earthquakes and of tsunami waves on the ocean by GNSS instruments on a buoy. Although GNSS-based precise positioning is a standard method, it is not yet common to apply this technique under tight time constraints and, hence, in the absence of precise satellite orbits and clocks. The new developed GNSS-based component utilises on- and offshore measured GNSS data and is the first system of its kind that was integrated into an operational early warning system. (Indonesian Tsunami Early Warning Centre INATEWS, inaugurated at BMKG, Jakarta on November, 11th 2008) Motivation After the Tsunami event of 26th December 2004 the German government initiated the GITEWS project (German Indonesian Tsunami Early Warning System) to develop a tsunami early warning system for Indonesia. The GFZ Potsdam (German Research Centre for Geosciences) as the consortial leader of GITEWS also covers several work packages, most of them related to sensor systems. The geodetic branch (Department 1) of the GFZ was assigned to develop a GNSS-based component. Brief system description The system covers all aspects from sensor stations with new developed hard- and software designs, manufacturing and installation of stations, real-time data transfer issues, a new developed automatic near real-time data processing and a graphical user interface for early warning centre operators including training on the system. GNSS sensors are installed on buoys, at tide gauges and as real-time reference stations (RTR stations), either stand-alone or co-located with seismic sensors. The GNSS data are transmitted to the warning centre where they are processed in a near real-time data processing chain. For

  10. The GNSS-based component for the new Indonesian tsunami early warning centre provided by GITEWS

    NASA Astrophysics Data System (ADS)

    Falck, C.; Ramatschi, M.; Bartsch, M.; Merx, A.; Hoeberechts, J.; Rothacher, M.

    2009-04-01

    Introduction Nowadays GNSS technologies are used for a large variety of precise positioning applications. The accuracy can reach the mm level depending on the data analysis methods. GNSS technologies thus offer a high potential to support tsunami early warning systems, e.g., by detection of ground motions due to earthquakes and of tsunami waves on the ocean by GNSS instruments on a buoy. Although GNSS-based precise positioning is a standard method, it is not yet common to apply this technique under tight time constraints and, hence, in the absence of precise satellite orbits and clocks. The new developed GNSS-based component utilises on- and offshore measured GNSS data and is the first system of its kind that was integrated into an operational early warning system. (Indonesian Tsunami Early Warning Centre INATEWS, inaugurated at BMKG, Jakarta on November, 11th 2008) Motivation After the Tsunami event of 26th December 2004 the German government initiated the GITEWS project (German Indonesian Tsunami Early Warning System) to develop a tsunami early warning system for Indonesia. The GFZ Potsdam (German Research Centre for Geosciences) as the consortial leader of GITEWS also covers several work packages, most of them related to sensor systems. The geodetic branch (Department 1) of the GFZ was assigned to develop a GNSS-based component. Brief system description The system covers all aspects from sensor stations with new developed hard- and software designs, manufacturing and installation of stations, real-time data transfer issues, a new developed automatic near real-time data processing and a graphical user interface for early warning centre operators including training on the system. GNSS sensors are installed on buoys, at tide gauges and as real-time reference stations (RTR stations), either stand-alone or co-located with seismic sensors. The GNSS data are transmitted to the warning centre where they are processed in a near real-time data processing chain. For

  11. High angle of attack position sensing for the Southampton University magnetic suspension and balance system

    NASA Technical Reports Server (NTRS)

    Parker, David H.

    1987-01-01

    An all digital five channel position detection system is to be installed in the Southampton University Magnetic Suspension and Balance System (SUMSBS). The system is intended to monitor a much larger range of model pitch attitudes than has been possible hitherto, up to a maximum of a 90 degree angle of attack. It is based on the use of self-scanning photodiode arrays and illuminating laser light beams, together with purpose built processing electronics. The principles behind the design of the system are discussed, together with the results of testing one channel of the system which was used to control the axial position of a magnetically suspended model in SUMSBS. The removal of optically coupled heave position information from the axial position sensing channel is described.

  12. A Novel General Imaging Formation Algorithm for GNSS-Based Bistatic SAR.

    PubMed

    Zeng, Hong-Cheng; Wang, Peng-Bo; Chen, Jie; Liu, Wei; Ge, LinLin; Yang, Wei

    2016-02-26

    Global Navigation Satellite System (GNSS)-based bistatic Synthetic Aperture Radar (SAR) recently plays a more and more significant role in remote sensing applications for its low-cost and real-time global coverage capability. In this paper, a general imaging formation algorithm was proposed for accurately and efficiently focusing GNSS-based bistatic SAR data, which avoids the interpolation processing in traditional back projection algorithms (BPAs). A two-dimensional point target spectrum model was firstly presented, and the bulk range cell migration correction (RCMC) was consequently derived for reducing range cell migration (RCM) and coarse focusing. As the bulk RCMC seriously changes the range history of the radar signal, a modified and much more efficient hybrid correlation operation was introduced for compensating residual phase errors. Simulation results were presented based on a general geometric topology with non-parallel trajectories and unequal velocities for both transmitter and receiver platforms, showing a satisfactory performance by the proposed method.

  13. A Novel General Imaging Formation Algorithm for GNSS-Based Bistatic SAR

    PubMed Central

    Zeng, Hong-Cheng; Wang, Peng-Bo; Chen, Jie; Liu, Wei; Ge, LinLin; Yang, Wei

    2016-01-01

    Global Navigation Satellite System (GNSS)-based bistatic Synthetic Aperture Radar (SAR) recently plays a more and more significant role in remote sensing applications for its low-cost and real-time global coverage capability. In this paper, a general imaging formation algorithm was proposed for accurately and efficiently focusing GNSS-based bistatic SAR data, which avoids the interpolation processing in traditional back projection algorithms (BPAs). A two-dimensional point target spectrum model was firstly presented, and the bulk range cell migration correction (RCMC) was consequently derived for reducing range cell migration (RCM) and coarse focusing. As the bulk RCMC seriously changes the range history of the radar signal, a modified and much more efficient hybrid correlation operation was introduced for compensating residual phase errors. Simulation results were presented based on a general geometric topology with non-parallel trajectories and unequal velocities for both transmitter and receiver platforms, showing a satisfactory performance by the proposed method. PMID:26927117

  14. A Novel General Imaging Formation Algorithm for GNSS-Based Bistatic SAR.

    PubMed

    Zeng, Hong-Cheng; Wang, Peng-Bo; Chen, Jie; Liu, Wei; Ge, LinLin; Yang, Wei

    2016-01-01

    Global Navigation Satellite System (GNSS)-based bistatic Synthetic Aperture Radar (SAR) recently plays a more and more significant role in remote sensing applications for its low-cost and real-time global coverage capability. In this paper, a general imaging formation algorithm was proposed for accurately and efficiently focusing GNSS-based bistatic SAR data, which avoids the interpolation processing in traditional back projection algorithms (BPAs). A two-dimensional point target spectrum model was firstly presented, and the bulk range cell migration correction (RCMC) was consequently derived for reducing range cell migration (RCM) and coarse focusing. As the bulk RCMC seriously changes the range history of the radar signal, a modified and much more efficient hybrid correlation operation was introduced for compensating residual phase errors. Simulation results were presented based on a general geometric topology with non-parallel trajectories and unequal velocities for both transmitter and receiver platforms, showing a satisfactory performance by the proposed method. PMID:26927117

  15. Primary Position Upbeat Nystagmus during an Acute Attack of Multiple Sclerosis

    PubMed Central

    Kim, Jee-Ae; Jeong, In-Hye; Lim, Young-Min

    2014-01-01

    Background and Purpose Ocular manifestation is one of the frequent signs of an acute attack in multiple sclerosis (MS), although primary position upbeat nystagmus (PPUN) is rare. The purpose of this study is to determine the incidence of PPUN in MS and to determine the lesions that are responsible for this sign. Methods The medical records of 120 MS patients with acute brain lesions were reviewed over a consecutive period of 9 years; of these, 6 patients were found to have PPUN. Other ocular motor abnormalities were analyzed in combination with upbeat nystagmus, video-oculographic findings, and lesions detected on brain MRI. Results Lesions in the pontine tegmentum involving the medial longitudinal fasciculus (MLF) and ventral tegmental tract (VTT) were the most common, being observed in three of the six patients with PPUN. One patient exhibited caudal medullary lesions bilaterally affecting the paramedian portion of the posterior tegmentum, and two patients exhibited multiple lesions involving the pons with the cerebral peduncle or medulla. In five patients, other ocular motor dysfunctions, such as gaze-evoked nystagmus (n=3) and internuclear ophthalmoplegia (n=1), were found in combination with upbeat nystagmus. Conclusions PPUN is an infrequent, ocular manifestation noted during an acute attack of MS, and was observed in 5% of the present cases. Brainstem lesions in these cases primarily involved the pontine tegmentum and the caudal medulla. These findings support the theory that upbeat nystagmus is attributable to damage to the upward vestibulo-ocular reflex pathway related to the vestibular nucleus, VTT, and interconnecting pathways. PMID:24465261

  16. Prototyping a GNSS-Based Passive Radar for UAVs: An Instrument to Classify the Water Content Feature of Lands.

    PubMed

    Gamba, Micaela Troglia; Marucco, Gianluca; Pini, Marco; Ugazio, Sabrina; Falletti, Emanuela; Lo Presti, Letizia

    2015-11-10

    Global Navigation Satellite Systems (GNSS) broadcast signals for positioning and navigation, which can be also employed for remote sensing applications. Indeed, the satellites of any GNSS can be seen as synchronized sources of electromagnetic radiation, and specific processing of the signals reflected back from the ground can be used to estimate the geophysical properties of the Earth's surface. Several experiments have successfully demonstrated GNSS-reflectometry (GNSS-R), whereas new applications are continuously emerging and are presently under development, either from static or dynamic platforms. GNSS-R can be implemented at a low cost, primarily if small devices are mounted on-board unmanned aerial vehicles (UAVs), which today can be equipped with several types of sensors for environmental monitoring. So far, many instruments for GNSS-R have followed the GNSS bistatic radar architecture and consisted of custom GNSS receivers, often requiring a personal computer and bulky systems to store large amounts of data. This paper presents the development of a GNSS-based sensor for UAVs and small manned aircraft, used to classify lands according to their soil water content. The paper provides details on the design of the major hardware and software components, as well as the description of the results obtained through field tests.

  17. Prototyping a GNSS-Based Passive Radar for UAVs: An Instrument to Classify the Water Content Feature of Lands

    PubMed Central

    Troglia Gamba, Micaela; Marucco, Gianluca; Pini, Marco; Ugazio, Sabrina; Falletti, Emanuela; Lo Presti, Letizia

    2015-01-01

    Global Navigation Satellite Systems (GNSS) broadcast signals for positioning and navigation, which can be also employed for remote sensing applications. Indeed, the satellites of any GNSS can be seen as synchronized sources of electromagnetic radiation, and specific processing of the signals reflected back from the ground can be used to estimate the geophysical properties of the Earth’s surface. Several experiments have successfully demonstrated GNSS-reflectometry (GNSS-R), whereas new applications are continuously emerging and are presently under development, either from static or dynamic platforms. GNSS-R can be implemented at a low cost, primarily if small devices are mounted on-board unmanned aerial vehicles (UAVs), which today can be equipped with several types of sensors for environmental monitoring. So far, many instruments for GNSS-R have followed the GNSS bistatic radar architecture and consisted of custom GNSS receivers, often requiring a personal computer and bulky systems to store large amounts of data. This paper presents the development of a GNSS-based sensor for UAVs and small manned aircraft, used to classify lands according to their soil water content. The paper provides details on the design of the major hardware and software components, as well as the description of the results obtained through field tests. PMID:26569242

  18. Prototyping a GNSS-Based Passive Radar for UAVs: An Instrument to Classify the Water Content Feature of Lands.

    PubMed

    Gamba, Micaela Troglia; Marucco, Gianluca; Pini, Marco; Ugazio, Sabrina; Falletti, Emanuela; Lo Presti, Letizia

    2015-01-01

    Global Navigation Satellite Systems (GNSS) broadcast signals for positioning and navigation, which can be also employed for remote sensing applications. Indeed, the satellites of any GNSS can be seen as synchronized sources of electromagnetic radiation, and specific processing of the signals reflected back from the ground can be used to estimate the geophysical properties of the Earth's surface. Several experiments have successfully demonstrated GNSS-reflectometry (GNSS-R), whereas new applications are continuously emerging and are presently under development, either from static or dynamic platforms. GNSS-R can be implemented at a low cost, primarily if small devices are mounted on-board unmanned aerial vehicles (UAVs), which today can be equipped with several types of sensors for environmental monitoring. So far, many instruments for GNSS-R have followed the GNSS bistatic radar architecture and consisted of custom GNSS receivers, often requiring a personal computer and bulky systems to store large amounts of data. This paper presents the development of a GNSS-based sensor for UAVs and small manned aircraft, used to classify lands according to their soil water content. The paper provides details on the design of the major hardware and software components, as well as the description of the results obtained through field tests. PMID:26569242

  19. High positive affect shortly after missile attacks and the heightened risk of posttraumatic stress disorder among Israeli adolescents.

    PubMed

    Israel-Cohen, Yael; Kashy-Rosenbaum, Gabriela; Kaplan, Oren

    2014-06-01

    Previous research has demonstrated that positive emotions help build psychological resources and facilitate adaptation to stress, yet few studies have considered the possible negative effects of positive emotions on stress. This study examined the relationship between high arousal, positive and negative affect, and posttraumatic stress disorder (PTSD) symptoms among 503 Israeli adolescents following a period of escalated missile attacks on their city. Our findings revealed that not only negative affect, but also positive affect at very high levels exhibited 2 weeks following missile attacks were independently associated with PTSD symptoms 2½ months later (η(2) = .09, η(2) = .02, respectively). Although the literature recognizes the risk factor of negative affect on the development of PTSD, we suggest that also positive affect at high levels immediately after such experiences may be a case of emotion context insensitivity and thus a maladaptive response to trauma. Further research should examine the mechanisms associated with positive emotions and PTSD.

  20. Performance Assessment of a Gnss-Based Troposphere Path Delay Estimation Software

    NASA Astrophysics Data System (ADS)

    Mariotti, Gilles; Avanzi, Alessandro; Graziani, Alberto; Tortora, Paolo

    2013-04-01

    Error budgets of Deep Space Radio Science experiments are heavily affected by interplanetary and Earth transmission media, that corrupt, due to their non-unitary refraction index, the radiometric information of signals coming from the spacecraft. An effective removal of these noise sources is crucial to achieve the accuracy and signal stability levels required by radio science applications. Depending on the nature of these refractions, transmission media are divided into dispersive (that consists of ionized particles, i.e. Solar Wind and Ionosphere) and non-dispersive ones (the refraction is caused by neutral particles: Earth Troposphere). While dispersive noises are successfully removed by multifrequency combinations (as for GPS with the well-known ionofree combination), the most accurate estimation of tropospheric noise is obtained using microwave radiometers (MWR). As the use of MWRs suffers from strong operational limitations (rain and heavy clouds conditions), the GNSS-based processing is still widely adopted to provide a cost-effective, all-weather condition estimation of the troposphere path delay. This work describes the development process and reports the results of a GNSS analysis code specifically aimed to the estimation of the path delays introduced by the troposphere above deep space complexes, to be used for the calibration of Range and Doppler radiometric data. The code has been developed by the Radio Science Laboratory of the University of Bologna in Forlì, and is currently in the testing phase. To this aim, the preliminary output is compared to MWR measurements and IGS TropoSINEX products in order to assess the reliability of the estimate. The software works using ionofree carrier-phase observables and is based upon a double-difference approach, in which the GNSS receiver placed nearby the Deep Space receiver acts as the rover station. Several baselines are then created with various IGS and EUREF stations (master or reference stations) in order to

  1. National Heart Attack Alert Program position paper: chest pain centers and programs for the evaluation of acute cardiac ischemia.

    PubMed

    Zalenski, R J; Selker, H P; Cannon, C P; Farin, H M; Gibler, W B; Goldberg, R J; Lambrew, C T; Ornato, J P; Rydman, R J; Steele, P

    2000-05-01

    The National Heart Attack Alert Program (NHAAP), which is coordinated by the National Heart, Lung, and Blood Institute (NHLBI), promotes the early detection and optimal treatment of patients with acute myocardial infarction and other acute coronary ischemic syndromes. The NHAAP, having observed the development and growth of chest pain centers in emergency departments with special interest, created a task force to evaluate such centers and make recommendations pertaining to the management of patients with acute cardiac ischemia. This position paper offers recommendations to assist emergency physicians in EDs, including those with chest pain centers, in providing comprehensive care for patients with acute cardiac ischemia. PMID:10783408

  2. Insecurity of position-based quantum-cryptography protocols against entanglement attacks

    SciTech Connect

    Lau, Hoi-Kwan; Lo, Hoi-Kwong

    2011-01-15

    Recently, position-based quantum cryptography has been claimed to be unconditionally secure. On the contrary, here we show that the existing proposals for position-based quantum cryptography are, in fact, insecure if entanglement is shared among two adversaries. Specifically, we demonstrate how the adversaries can incorporate ideas of quantum teleportation and quantum secret sharing to compromise the security with certainty. The common flaw to all current protocols is that the Pauli operators always map a codeword to a codeword (up to an irrelevant overall phase). We propose a modified scheme lacking this property in which the same cheating strategy used to undermine the previous protocols can succeed with a rate of at most 85%. We prove the modified protocol is secure when the shared quantum resource between the adversaries is a two- or three-level system.

  3. Insecurity of position-based quantum-cryptography protocols against entanglement attacks

    NASA Astrophysics Data System (ADS)

    Lau, Hoi-Kwan; Lo, Hoi-Kwong

    2011-01-01

    Recently, position-based quantum cryptography has been claimed to be unconditionally secure. On the contrary, here we show that the existing proposals for position-based quantum cryptography are, in fact, insecure if entanglement is shared among two adversaries. Specifically, we demonstrate how the adversaries can incorporate ideas of quantum teleportation and quantum secret sharing to compromise the security with certainty. The common flaw to all current protocols is that the Pauli operators always map a codeword to a codeword (up to an irrelevant overall phase). We propose a modified scheme lacking this property in which the same cheating strategy used to undermine the previous protocols can succeed with a rate of at most 85%. We prove the modified protocol is secure when the shared quantum resource between the adversaries is a two- or three-level system.

  4. The GNSS-based Ground Tracking System (GTS) of GFZ; from GITEWS to PROTECTS and beyond

    NASA Astrophysics Data System (ADS)

    Falck, Carsten; Merx, Alexander; Ramatschi, Markus

    2013-04-01

    Introduction An automatic system for the near real-time determination and visualization of ground motions, respectively co-seismic deformations of the Earth's surface, was developed by GFZ (German Research Centre for Geosciences) within the project GITEWS (German Indonesian Tsunami Early Warning System). The system is capable to deliver 3D-displacement vectors for locations with appropriate GPS-equipment in the vicinity of an earthquake's epicenter with a delay of only a few minutes. These vectors can help to assess the earthquake causing tectonic movements, which must be known to make reliable early warning predictions, e.g., concerning the generation of tsunami waves. The GTS (Ground Tracking System) has been integrated into InaTEWS (Indonesian Tsunami Early Warning System) and is in operation at the national warning center in Jakarta since November 2008. After the end of the project GITEWS GFZ continues to support the GTS in Indonesia within the frame of PROTECTS (Project for Training, Education and Consulting for Tsunami Early Warning Systems) and recently some new developments have been introduced. We now aim to make further use of the achievements made, e.g., by developing a license model for the GTS software package. Motivation After the Tsunami of 26th December 2004 the German government initiated the GITEWS project to develop the main components for a tsunami early warning system in Indonesia. The GFZ, as the consortial leader of GITEWS, had several work packages, most of them related to sensor systems. The geodetic branch (Department 1) of GFZ was assigned to develop a GNSS-based component, which since then is known as the GTS (Ground Tracking System). System benefit The ground motion information delivered by the GTS is a valuable source for a fast understanding of an earthquake's mechanism with a high relevance to assess the probability and magnitude of a potentially following tsunami. The system may detect highest displacement vector values, where

  5. The GNSS-based Ground Tracking System (GTS) of GFZ; from GITEWS to PROTECTS and beyond

    NASA Astrophysics Data System (ADS)

    Falck, Carsten; Merx, Alexander; Ramatschi, Markus

    2013-04-01

    Introduction An automatic system for the near real-time determination and visualization of ground motions, respectively co-seismic deformations of the Earth's surface, was developed by GFZ (German Research Centre for Geosciences) within the project GITEWS (German Indonesian Tsunami Early Warning System). The system is capable to deliver 3D-displacement vectors for locations with appropriate GPS-equipment in the vicinity of an earthquake's epicenter with a delay of only a few minutes. These vectors can help to assess the earthquake causing tectonic movements, which must be known to make reliable early warning predictions, e.g., concerning the generation of tsunami waves. The GTS (Ground Tracking System) has been integrated into InaTEWS (Indonesian Tsunami Early Warning System) and is in operation at the national warning center in Jakarta since November 2008. After the end of the project GITEWS GFZ continues to support the GTS in Indonesia within the frame of PROTECTS (Project for Training, Education and Consulting for Tsunami Early Warning Systems) and recently some new developments have been introduced. We now aim to make further use of the achievements made, e.g., by developing a license model for the GTS software package. Motivation After the Tsunami of 26th December 2004 the German government initiated the GITEWS project to develop the main components for a tsunami early warning system in Indonesia. The GFZ, as the consortial leader of GITEWS, had several work packages, most of them related to sensor systems. The geodetic branch (Department 1) of GFZ was assigned to develop a GNSS-based component, which since then is known as the GTS (Ground Tracking System). System benefit The ground motion information delivered by the GTS is a valuable source for a fast understanding of an earthquake's mechanism with a high relevance to assess the probability and magnitude of a potentially following tsunami. The system may detect highest displacement vector values, where

  6. Heart attack

    MedlinePlus

    ... infarction; Non-ST - elevation myocardial infarction; NSTEMI; CAD - heart attack; Coronary artery disease - heart attack ... made up of cholesterol and other cells. A heart attack may occur when: A tear in the ...

  7. Heart Attack

    MedlinePlus

    ... attack treatment works best when it's given right after symptoms occur. Prompt treatment of a heart attack can help prevent or limit damage to the heart and prevent sudden death. Call 9-1-1 Right Away A heart ...

  8. Relative receiver autonomous integrity monitoring for future GNSS-based aircraft navigation

    NASA Astrophysics Data System (ADS)

    Gratton, Livio Rafael

    The Global Positioning System (GPS) has enabled reliable, safe, and practical aircraft positioning for en-route and non-precision phases of flight for more than a decade. Intense research is currently devoted to extending the use of Global Navigation Satellite Systems (GNSS), including GPS, to precision approach and landing operations. In this context, this work is focused on the development, analysis, and verification of the concept of Relative Receiver Autonomous Integrity Monitoring (RRAIM) and its potential applications to precision approach navigation. RRAIM fault detection algorithms are developed, and associated mathematical bounds on position error are derived. These are investigated as possible solutions to some current key challenges in precision approach navigation, discussed below. Augmentation systems serving continent-size areas (like the Wide Area Augmentation System or WAAS) allow certain precision approach operations within the covered region. More and better satellites, with dual frequency capabilities, are expected to be in orbit in the mid-term future, which will potentially allow WAAS-like capabilities worldwide with a sparse ground station network. Two main challenges in achieving this goal are (1) ensuring that navigation fault detection functions are fast enough to alert worldwide users of hazardously misleading information, and (2) minimizing situations in which navigation is unavailable because the user's local satellite geometry is insufficient for safe position estimation. Local augmentation systems (implemented at individual airports, like the Local Area Augmentation System or LAAS) have the potential to allow precision approach and landing operations by providing precise corrections to user-satellite range measurements. An exception to these capabilities arises during ionospheric storms (caused by solar activity), when hazardous situations can exist with residual range errors several orders of magnitudes higher than nominal. Until dual

  9. GNSS-based Observations and Simulations of Spectral Scintillation Indices in the Arctic Ionosphere

    NASA Astrophysics Data System (ADS)

    Durgonics, T.; Hoeg, P.; von Benzon, H. H.; Komjathy, A.

    2015-12-01

    During disturbed times, ionospheric scintillations can be severe and adversely impact satellite-based positioning and radio transmissions. The scintillation occurs in the amplitude, phase, polarization, and angle of arrival of the signal. Precise observation, classification, modeling, forecasting, and development of data-driven methodologies to accurately localize ionospheric irregularities and simulate GNSS scintillation signals are highly desired. Ionospheric scintillations have traditionally been quantified by amplitude (S4) and phase scintillations (σφ). Our study focuses on the Arctic, where scintillations, especially phase scintillations, are prominent. We will present observations acquired from a network of Greenlandic GNSS stations, including 2D amplitude and phase scintillation index maps for representative calm and storm periods. In addition to the traditional indices described above, we are exploring a set of indices derived from the power spectra of the signals. The observed corner frequency of the power spectrum is a function of the Fresnel radius and the drift speed of the irregularities, while the slope of the power spectrum is related to the Fresnel oscillations. We will demonstrate how spectral characteristics of the scintillations act under large total electron content (TEC) gradients and how physical parameters can be extracted from the power spectra, and will present how these parameters of the corner frequencies and power spectra slopes vary during ionospheric storms. The observations will then be compared to properties of simulated GNSS signals computed by the Fast Scintillation Mode (FSM). The FSM was developed to simulate ionospheric scintillations under different geophysical conditions, and is used to simulate GNSS signals with known scintillation characteristics. This comparison could lead to a better understanding of the observed ionospheric state.

  10. Water Vapour GNSS Based Tomography For Wet Delay Compensation In In-SAR Applications

    NASA Astrophysics Data System (ADS)

    Notarpietro, Riccardo; Cucca, Manuela; Perona, Giovanni

    2010-05-01

    One of the most challenging exploitation of GNSS signals for meteorological applications is the retrieval of Water Vapor tridimensional distribution. The real-time (or quasi real-time) knowledge of such distributions could be very useful for several applications: from operative meteorology to atmospheric modeling, or for atmospheric compensation purposes applied for example to SAR or In-SAR observations, in order to improve land remote sensing. In the framework of the European Space Agency project METAWAVE (Mitigation of Electromagnetic Transmission errors induced by Atmospheric Water Vapor Effects), several techniques were investigated in order to find out an In-SAR data compensation strategy for the propagation delay effects due to Water Vapour. Thanks to METAWAVE, a quite dense GPS network (7 dual frequency GPS receivers) was deployed over COMO area and was used for an extensive measurement campaign. The acquired L1 and L2 carrier phase observations were processed in terms of hourly averaged Zenith Wet Delays. These vertical information were mapped along the correspondent line of sights (by up-sampling at 30 second sample times the 15 minutes GPS satellites positions obtained from IGS files) and inverted using a tomographic procedure. The used algorithm performs a first reconstruction (namely, the tomographic pre-processing) based on generalized inversion mechanisms, in order to define a low resolution first guess for the next step. This second step inverts GPS observables using a more refined algebraic tomographic reconstruction algorithm, to improve both vertical and horizontal resolution. Results of this inversion are Wet Refractivity maps distributed over an area of 16 km x 20 km (x 10 km height) around the COMO city, characterized by horizontal resolutions varying from 2 km to 4 km and vertical resolution of 500m. This contribution deals with the description of the results obtained evaluating Water Vapour path delays from such Wet Refractivity maps

  11. Investigations on the Influence of Antenna Near-field Effects and Satellite Obstruction on the Uncertainty of GNSS-based Distance Measurements

    NASA Astrophysics Data System (ADS)

    Zimmermann, Florian; Eling, Christian; Kuhlmann, Heiner

    2016-03-01

    Antenna near-field effects are one of the accuracy limiting factors on GNSS-based distance measurements. In order to analyse these influences, a measurement campaign at an EDM calibration baseline site with optimum GNSS conditions was performed. To vary the distance between the antenna mount and the absolutely calibrated antennas, spacers with different lengths were used. Due to the comparison of the resulting GNSS-based distance measurements to a reference solution, the influences of the antenna near-field could be analyzed. The standard deviations of the differences to the reference solution, i. e., 0.31 mm for the distance and 0.46 mm for the height component, indicate that equal spacer and antenna combinations at both stations lead to a very high accuracy level. In contrast, different spacer and antenna combinations decrease the accuracy level. Thus, an identical set-up at both antenna stations and the usage of individually calibrated antennas minimize the near-field effects during the double-differencing process. Hence, these aspects can be identified as a prerequisite for highly accurate GNSS-measurements. In addition to near-field effects, the influence of satellite obstructions is investigated. Four realistic shadowing scenarios are numerically simulated on the basis of the observations, which were collected in the optimum surrounding of the EDM calibration baseline site. The comparison to nominal values indicates that a shadowing leads only to a slight decreasing of the accuracy. Consequently, there is a strong suspicion that multipath effects and signal distortions seem to have a greater influence on the accuracy of GNSS-based distance measurements than the satellite constellation.

  12. Heart Attack

    MedlinePlus

    ... a million people in the U.S. have a heart attack. About half of them die. Many people have permanent heart damage or die because they don't get ... It's important to know the symptoms of a heart attack and call 9-1-1 if someone ...

  13. Heart Attack

    MedlinePlus

    ... lower “bad” cholesterol (also called LDL, or low-density lipoprotein) levels and may help increase “good” cholesterol (also called HDL, or high-density lipoprotein). If you have had a heart attack, ...

  14. Shark attack.

    PubMed

    Guidera, K J; Ogden, J A; Highhouse, K; Pugh, L; Beatty, E

    1991-01-01

    Shark attacks are rare but devastating. This case had major injuries that included an open femoral fracture, massive hemorrhage, sciatic nerve laceration, and significant skin and muscle damage. The patient required 15 operative procedures, extensive physical therapy, and orthotic assistance. A review of the literature pertaining to shark bites is included.

  15. Facial dog attack injuries.

    PubMed

    Lin, Wei; Patil, Pavan Manohar

    2015-02-01

    The exposed position of the face makes it vulnerable to dog bite injuries. This fact combined with the short stature of children makes them a high-risk group for such attacks. In contrast to wounds inflicted by assaults and accidents, dog bite wounds are deep puncture type wounds compounded by the presence of pathologic bacteria from the saliva of the attacking dog. This, combined with the presence of crushed, devitalized tissue makes these wounds highly susceptible to infection. Key to successful management of such wounds are meticulous cleansing of the wound, careful debridement, primary repair, appropriate antibiotic therapy, and rabies and tetanus immunization where indicated. This review presents an overview of the epidemiology, presentation, management of such emergencies, and the recent advances in the care of such patients. PMID:25829713

  16. Heart Attack Recovery FAQs

    MedlinePlus

    ... Pressure High Blood Pressure Tools & Resources Stroke More Heart Attack Recovery FAQs Updated:Aug 24,2016 Most people ... recovery. View an animation of a heart attack . Heart Attack Recovery Questions and Answers What treatments will I ...

  17. Investigation of GNSS Based ERP-series to Validate Atmospheric and Oceanic Contributions to High Frequency Earth Rotation

    NASA Astrophysics Data System (ADS)

    Weber, R.; Nastula, J.; Boehm, S.

    2009-12-01

    Over the past 25 years several authors have shown that polar motions and variations of Universal Time (UT1) or length of day (LOD), respectively, from seasonal time scales down to one week are forced to a great extent by atmospheric and oceanic angular momentum (AAM and OAM) changes (Barnes, 1983; Rosen and Salstein, 1983; Brzezinski, 1992, 1994; Nastula and Salstein, 1999; Kolaczek et al., 2000; Nastula et al., 2002; Ponte and Ali,2002) and by the solid Earth tides and ocean tides. Oceanic tides also cause variations in UT1/LOD and in polar motion in particular at shorter time scales with diurnal and semi-diurnal periods. Theoretical and semi-empirical models were published by e.g. Gross (1993), Ray et al. (1994). All studies were based on ocean tide models or were using ocean tidal measurements by satellite altimetry. The Ray et al. (1994) model based on TOPEX/Poseidon satellite altimetry data is still the model which is recommended in the IERS Conventions 2003. The high-frequency variations of the Earth rotation parameters due to ocean tides can also be empirically determined from time series derived by space geodetic techniques like Very Long Baseline Interferometry (VLBI) or the Global Positioning System (GPS). Within this investigation high-quality ERP (Earth Rotation Parameter) series, i.e. polar motion (PM), and UT1 or length of day (LOD) with a time resolution of one hour have been established by processing observation data from both active GNSS-systems (GPS+GLONASS). Their correlation with oceanic- (OAM) and atmospheric-induced angular momentum (AAM) acting on the Earth’s surface are investigated. The investigations concentrate on short period variations of Earth rotation with periods of a few days down to a few hours. The amplitudes and phases of these short period tidally and non-tidally induced variations are compared to recent semi-empirical models of the oceanic and atmospheric excitation. Contrary to the standard processing scheme an improved

  18. Investigation on the movement of vortex burst position with dynamically changing angle of attack for a schematic deltawing in a watertunnel with correlation to similar studies in windtunnel

    NASA Astrophysics Data System (ADS)

    Wolffelt, Karl W.

    1987-06-01

    The requirements for modern military aircraft to maintain good handling qualities at very high angles of attack is one of many reasons why an increased knowledge is necessary regarding the aerodynamic behavior of vortex flows at nonstationary conditions. Linearized theory as it has been utilized in flight mechanics simulation using damping derivatives derived from forced oscillation technique, for example, may no longer be valid at such conditions. With this background some investigations have been made by SAAB-SCANIA with the aim to study the hysteresis effects for nonstationary vortex flows. A schematic delta-wing model which could also be equipped with a similar canard wing has been tested in a water tunnel. The model was supported in the tunnel by a simple mechanism by which it could be forced to move in one of four different modes, pitching or plunging with either ramp or harmonic motion. The flow over the model was visualized with air bubbles and sequences were recorded on videotape. The sequences were analyzed and the movements of the leading edge vortex burst have been studied with the main interest focused on the hysteresis effects.

  19. About Heart Attacks

    MedlinePlus

    ... survive. A heart attack occurs when the blood flow that brings oxygen to the heart muscle is severely reduced or ... survive. A heart attack occurs when the blood flow that brings oxygen to the heart muscle is severely reduced or ...

  20. Seven Deadliest Network Attacks

    SciTech Connect

    Prowell, Stacy J; Borkin, Michael; Kraus, Robert

    2010-05-01

    Do you need to keep up with the latest hacks, attacks, and exploits effecting networks? Then you need "Seven Deadliest Network Attacks". This book pinpoints the most dangerous hacks and exploits specific to networks, laying out the anatomy of these attacks including how to make your system more secure. You will discover the best ways to defend against these vicious hacks with step-by-step instruction and learn techniques to make your computer and network impenetrable. Attacks detailed in this book include: Denial of Service; War Dialing; Penetration 'Testing'; Protocol Tunneling; Spanning Tree Attacks; Man-in-the-Middle; and, Password Replay. Knowledge is power, find out about the most dominant attacks currently waging war on computers and networks globally. Discover the best ways to defend against these vicious attacks; step-by-step instruction shows you how. Institute countermeasures, don't be caught defenseless again, learn techniques to make your computer and network impenetrable.

  1. Wild boar attacks.

    PubMed

    Gunduz, Abdulkadir; Turedi, Suleyman; Nuhoglu, Irfan; Kalkan, Asim; Turkmen, Suha

    2007-01-01

    Attacks on humans by wild boar (Sus scrofa) are occasionally reported in rural areas of Turkey. While fatalities are rare, individuals may sustain significant soft tissue trauma. Lower extremity lacerations of up to 10 cm in length and 4 cm deep were seen in the 3 cases reviewed. Injuries to the upper abdomen and chest occurred in one case. Attacks frequently occur in forested areas covered by dense brushwood, and their incidence is increased during the rutting season. In contrast to other large, feral animal attacks, injuries sustained from wild boar typically are limited to the lower extremities. This case series examines 3 attacks by wild boar in rural Turkey.

  2. Transient Ischemic Attack

    MedlinePlus

    Transient Ischemic Attack TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood clot blocks an artery for a short time. The only ... TIA is that with TIA the blockage is transient (temporary). TIA symptoms occur rapidly and last a ...

  3. Signs of a Heart Attack

    MedlinePlus

    ... attack Heart Health and Stroke Signs of a heart attack Related information Make the Call. Don't Miss ... to top More information on Signs of a heart attack Read more from womenshealth.gov Make the Call, ...

  4. A fatal leopard attack.

    PubMed

    Hejna, Petr

    2010-05-01

    A rare case of a big cat fatal attack is presented. A male leopard that had escaped from its unlocked cage attacked a 26-year-old male zoo worker. The man sustained penetrating injuries to the neck with consequent external bleeding. The man died while being transported to the hospital as a result of the injuries sustained. The wounds discovered on the victim's body corresponded with the known methods of leopard attacks and with findings on the carcasses of animals killed by leopards in the wild. The conclusion of the medicolegal investigation was that the underlying cause of death was a bite wound to the neck which lacerated the left internal jugular vein, the two main branches of the left external carotid artery, and the cervical spine. The cause of death was massive external bleeding. Special attention is paid to the general pattern of injuries sustained from big cat attacks.

  5. Heart attack first aid

    MedlinePlus

    First aid - heart attack; First aid - cardiopulmonary arrest; First aid - cardiac arrest ... of patients with unstable angina/non-ST-elevation myocardial infarction (updating the 2007 guideline and replacing the 2011 ...

  6. Cooperating attackers in neural cryptography.

    PubMed

    Shacham, Lanir N; Klein, Einat; Mislovaty, Rachel; Kanter, Ido; Kinzel, Wolfgang

    2004-06-01

    A successful attack strategy in neural cryptography is presented. The neural cryptosystem, based on synchronization of neural networks by mutual learning, has been recently shown to be secure under different attack strategies. The success of the advanced attacker presented here, called the "majority-flipping attacker," does not decay with the parameters of the model. This attacker's outstanding success is due to its using a group of attackers which cooperate throughout the synchronization process, unlike any other attack strategy known. An analytical description of this attack is also presented, and fits the results of simulations.

  7. Collaborative Attack vs. Collaborative Defense

    NASA Astrophysics Data System (ADS)

    Xu, Shouhuai

    We have witnessed many attacks in the cyberspace. However, most attacks are launched by individual attackers even though an attack may involve many compromised computers. In this paper, we envision what we believe to be the next generation cyber attacks — collaborative attacks. Collaborative attacks can be launched by multiple attackers (i.e., human attackers or criminal organizations), each of which may have some specialized expertise. This is possible because cyber attacks can become very sophisticated and specialization of attack expertise naturally becomes relevant. To counter collaborative attacks, we might need collaborative defense because each “chain” in a collaborative attack may be only adequately dealt with by a different defender. In order to understand collaborative attack and collaborative defense, we present a high-level abstracted framework for evaluating the effectiveness of collaborative defense against collaborative attacks. As a first step towards realizing and instantiating the framework, we explore a characterization of collaborative attacks and collaborative defense from the relevant perspectives.

  8. Shark attack in Natal.

    PubMed

    White, J A

    1975-02-01

    The injuries in 5 cases of shark attack in Natal during 1973-74 are reviewed. Experience in shark attacks in South Africa during this period is discussed (1965-73), and the value of protecting heavily utilized beaches in Natal with nets is assessed. The surgical applications of elasmobranch research at the Oceanographic Research Institute (Durban) and at the Headquarters of the Natal Anti-Shark Measures Board (Umhlanga Rocks) are described. Modern trends in the training of surf life-guards, the provision of basic equipment for primary resuscitation of casualties on the beaches, and the policy of general and local care of these patients in Natal are discussed.

  9. Fatal crocodile attack.

    PubMed

    Chattopadhyay, Saurabh; Shee, Biplab; Sukul, Biswajit

    2013-11-01

    Attacks on human beings by various animals leading to varied types of injuries and even death in some cases are not uncommon. Crocodile attacks on humans have been reported from a number of countries across the globe. Deaths in such attacks are mostly due to mechanical injuries or drowning. Bites by the crocodiles often cause the limbs to be separated from the body. The present case refers to an incident of a fatal attack by a crocodile on a 35 years old female where only the mutilated head of the female was recovered. Multiple lacerated wounds over the face and scalp along with fracture of the cranial bones was detected on autopsy. Two distinct bite marks in the form of punched in holes were noted over the parietal and frontal bones. Injuries on the head with its traumatic amputation from the body were sufficient to cause death. However, the presence of other fatal injuries on the unrecovered body parts could not be ruled out.

  10. Word Attack Model.

    ERIC Educational Resources Information Center

    Follettie, Joseph F.

    A limited analysis of alternative approaches to phonemic-level word attack instruction is provided in this document. The instruction segment begins with training in letter-sound correspondences for which mastery of certain skills is assumed. Instruction ends with the decoding of novel items having a consonant-vowel-consonant construction. Contents…

  11. Using residual stacking to mitigate site-specific errors in order to improve the quality of GNSS-based coordinate time series of CORS

    NASA Astrophysics Data System (ADS)

    Knöpfler, Andreas; Mayer, Michael; Heck, Bernhard

    2014-05-01

    Within the last decades, positioning using GNSS (Global Navigation Satellite Systems; e.g., GPS) has become a standard tool in many (geo-) sciences. The positioning methods Precise Point Positioning and differential point positioning based on carrier phase observations have been developed for a broad variety of applications with different demands for example on accuracy. In high precision applications, a lot of effort was invested to mitigate different error sources: the products for satellite orbits and satellite clocks were improved; the misbehaviour of satellite and receiver antennas compared to an ideal antenna is modelled by calibration values on absolute level, the modelling of the ionosphere and the troposphere is updated year by year. Therefore, within processing of data of CORS (continuously operating reference sites), equipped with geodetic hardware using a sophisticated strategy, the latest products and models nowadays enable positioning accuracies at low mm level. Despite the considerable improvements that have been achieved within GNSS data processing, a generally valid multipath model is still lacking. Therefore, site specific multipath still represents a major error source in precise GNSS positioning. Furthermore, the calibration information of receiving GNSS antennas, which is for instance derived by a robot or chamber calibration, is valid strictly speaking only for the location of the calibration. The calibrated antenna can show a slightly different behaviour at the CORS due to near field multipath effects. One very promising strategy to mitigate multipath effects as well as imperfectly calibrated receiver antennas is to stack observation residuals of several days, thereby, multipath-loaded observation residuals are analysed for example with respect to signal direction, to find and reduce systematic constituents. This presentation will give a short overview about existing stacking approaches. In addition, first results of the stacking approach

  12. Maintaining defender's reputation in anomaly detection against insider attacks.

    PubMed

    Zhang, Nan; Yu, Wei; Fu, Xinwen; Das, Sajal K

    2010-06-01

    We address issues related to establishing a defender's reputation in anomaly detection against two types of attackers: 1) smart insiders, who learn from historic attacks and adapt their strategies to avoid detection/punishment, and 2) naïve attackers, who blindly launch their attacks without knowledge of the history. In this paper, we propose two novel algorithms for reputation establishment--one for systems solely consisting of smart insiders and the other for systems in which both smart insiders and naïve attackers are present. The theoretical analysis and performance evaluation show that our reputation-establishment algorithms can significantly improve the performance of anomaly detection against insider attacks in terms of the tradeoff between detection and false positives.

  13. Improving Attack Graph Visualization through Data Reduction and Attack Grouping

    SciTech Connect

    John Homer; Ashok Varikuti; Xinming Ou; Miles A. McQueen

    2008-09-01

    Various tools exist to analyze enterprise network systems and to produce attack graphs detailing how attackers might penetrate into the system. These attack graphs, however, are often complex and difficult to comprehend fully, and a human user may find it problematic to reach appropriate configuration decisions. This paper presents methodologies that can 1) automatically identify portions of an attack graph that do not help a user to understand the core security problems and so can be trimmed, and 2) automatically group similar attack steps as virtual nodes in a model of the network topology, to immediately increase the understandability of the data. We believe both methods are important steps toward improving visualization of attack graphs to make them more useful in configuration management for large enterprise networks. We implemented our methods using one of the existing attack-graph toolkits. Initial experimentation shows that the proposed approaches can 1) significantly reduce the complexity of attack graphs by trimming a large portion of the graph that is not needed for a user to understand the security problem, and 2) significantly increase the accessibility and understandability of the data presented in the attack graph by clearly showing, within a generated visualization of the network topology, the number and type of potential attacks to which each host is exposed.

  14. The Electron Density Features Revealed by the GNSS-Based Radio Tomography in the Different Latitudinal and Longitudinal Sectors of the Ionosphere

    NASA Astrophysics Data System (ADS)

    Andreeva, Elena; Tereshchenko, Evgeniy; Nazarenko, Marina; Nesterov, Ivan; Kozharin, Maksim; Padokhin, Artem; Tumanova, Yulia

    2016-04-01

    requires a dedicated study. We present the examples of the both types of the structures. We show a collection of different ionospheric structures under different space weather conditions: the ionization troughs, with their widely varying shapes, depths, positions, and internal distributions of plasma; isolated spots of the increased or decreased electron density, sharp wall-like density gradients, blobs, wavelike disturbances on different spatiotemporal scales etc. We demonstrate the series of the local isolated irregularities which are observed during both the quiet and disturbed days. We show the examples of the ionospheric plasma distributions strikingly varying during the geomagnetic storms. Some of the RT data are compared to the independent observations by the ionosondes. We also present the examples of RT images comparison with the UV spectroscopy data.

  15. Sulfate attack expansion mechanisms

    SciTech Connect

    Müllauer, Wolfram Beddoe, Robin E.; Heinz, Detlef

    2013-10-15

    A specially constructed stress cell was used to measure the stress generated in thin-walled Portland cement mortar cylinders caused by external sulfate attack. The effects of sulfate concentration of the storage solution and C{sub 3}A content of the cement were studied. Changes in mineralogical composition and pore size distribution were investigated by X-ray diffraction and mercury intrusion porosimetry, respectively. Damage is due to the formation of ettringite in small pores (10–50 nm) which generates stresses up to 8 MPa exceeding the tensile strength of the binder matrix. Higher sulfate concentrations and C{sub 3}A contents result in higher stresses. The results can be understood in terms of the effect of crystal surface energy and size on supersaturation and crystal growth pressure.

  16. WILD PIG ATTACKS ON HUMANS

    SciTech Connect

    Mayer, J.

    2013-04-12

    Attacks on humans by wild pigs (Sus scrofa) have been documented since ancient times. However, studies characterizing these incidents are lacking. In an effort to better understand this phenomenon, information was collected from 412 wild pig attacks on humans. Similar to studies of large predator attacks on humans, data came from a variety of sources. The various attacks compiled occurred in seven zoogeographic realms. Most attacks occurred within the species native range, and specifically in rural areas. The occurrence was highest during the winter months and daylight hours. Most happened under non-hunting circumstances and appeared to be unprovoked. Wounded animals were the chief cause of these attacks in hunting situations. The animals involved were typically solitary, male and large in size. The fate of the wild pigs involved in these attacks varied depending upon the circumstances, however, most escaped uninjured. Most human victims were adult males traveling on foot and alone. The most frequent outcome for these victims was physical contact/mauling. The severity of resulting injuries ranged from minor to fatal. Most of the mauled victims had injuries to only one part of their bodies, with legs/feet being the most frequent body part injured. Injuries were primarily in the form of lacerations and punctures. Fatalities were typically due to blood loss. In some cases, serious infections or toxemia resulted from the injuries. Other species (i.e., pets and livestock) were also accompanying some of the humans during these attacks. The fates of these animals varied from escaping uninjured to being killed. Frequency data on both non-hunting and hunting incidents of wild pig attacks on humans at the Savannah River Site, South Carolina, showed quantitatively that such incidents are rare.

  17. Genetic attack on neural cryptography.

    PubMed

    Ruttor, Andreas; Kinzel, Wolfgang; Naeh, Rivka; Kanter, Ido

    2006-03-01

    Different scaling properties for the complexity of bidirectional synchronization and unidirectional learning are essential for the security of neural cryptography. Incrementing the synaptic depth of the networks increases the synchronization time only polynomially, but the success of the geometric attack is reduced exponentially and it clearly fails in the limit of infinite synaptic depth. This method is improved by adding a genetic algorithm, which selects the fittest neural networks. The probability of a successful genetic attack is calculated for different model parameters using numerical simulations. The results show that scaling laws observed in the case of other attacks hold for the improved algorithm, too. The number of networks needed for an effective attack grows exponentially with increasing synaptic depth. In addition, finite-size effects caused by Hebbian and anti-Hebbian learning are analyzed. These learning rules converge to the random walk rule if the synaptic depth is small compared to the square root of the system size.

  18. Genetic attack on neural cryptography

    SciTech Connect

    Ruttor, Andreas; Kinzel, Wolfgang; Naeh, Rivka; Kanter, Ido

    2006-03-15

    Different scaling properties for the complexity of bidirectional synchronization and unidirectional learning are essential for the security of neural cryptography. Incrementing the synaptic depth of the networks increases the synchronization time only polynomially, but the success of the geometric attack is reduced exponentially and it clearly fails in the limit of infinite synaptic depth. This method is improved by adding a genetic algorithm, which selects the fittest neural networks. The probability of a successful genetic attack is calculated for different model parameters using numerical simulations. The results show that scaling laws observed in the case of other attacks hold for the improved algorithm, too. The number of networks needed for an effective attack grows exponentially with increasing synaptic depth. In addition, finite-size effects caused by Hebbian and anti-Hebbian learning are analyzed. These learning rules converge to the random walk rule if the synaptic depth is small compared to the square root of the system size.

  19. Attack vulnerability of complex networks

    NASA Astrophysics Data System (ADS)

    Holme, Petter; Kim, Beom Jun; Yoon, Chang No; Han, Seung Kee

    2002-05-01

    We study the response of complex networks subject to attacks on vertices and edges. Several existing complex network models as well as real-world networks of scientific collaborations and Internet traffic are numerically investigated, and the network performance is quantitatively measured by the average inverse geodesic length and the size of the largest connected subgraph. For each case of attacks on vertices and edges, four different attacking strategies are used: removals by the descending order of the degree and the betweenness centrality, calculated for either the initial network or the current network during the removal procedure. It is found that the removals by the recalculated degrees and betweenness centralities are often more harmful than the attack strategies based on the initial network, suggesting that the network structure changes as important vertices or edges are removed. Furthermore, the correlation between the betweenness centrality and the degree in complex networks is studied.

  20. Resource distribution in multiple attacks with imperfect detection of the attack outcome.

    PubMed

    Levitin, Gregory; Hausken, Kjell

    2012-02-01

    This article extends the previous research of consecutive attacks strategy by assuming that an attacker observes the outcome of each attack imperfectly. With given probabilities it may wrongly identify a destroyed target as undestroyed, and wrongly identify an undestroyed target as destroyed. The outcome of each attack is determined by a contest success function that depends on the amount of resources allocated by the defender and the attacker to each attack. The article suggests a probabilistic model of the multiple attacks and analyzes how the target destruction probability and the attacker's relative resource expenditure are impacted by the two probabilities of incorrect observation, the attacker's and defender's resource ratio, the contest intensity, the number of attacks, and the resource distribution across attacks. We analyze how the attacker chooses the number of attacks, the attack stopping rule, and the optimal resource distribution across attacks to maximize its utility.

  1. Additive attacks on speaker recognition

    NASA Astrophysics Data System (ADS)

    Farrokh Baroughi, Alireza; Craver, Scott

    2014-02-01

    Speaker recognition is used to identify a speaker's voice from among a group of known speakers. A common method of speaker recognition is a classification based on cepstral coefficients of the speaker's voice, using a Gaussian mixture model (GMM) to model each speaker. In this paper we try to fool a speaker recognition system using additive noise such that an intruder is recognized as a target user. Our attack uses a mixture selected from a target user's GMM model, inverting the cepstral transformation to produce noise samples. In our 5 speaker data base, we achieve an attack success rate of 50% with a noise signal at 10dB SNR, and 95% by increasing noise power to 0dB SNR. The importance of this attack is its simplicity and flexibility: it can be employed in real time with no processing of an attacker's voice, and little computation is needed at the moment of detection, allowing the attack to be performed by a small portable device. For any target user, knowing that user's model or voice sample is sufficient to compute the attack signal, and it is enough that the intruder plays it while he/she is uttering to be classiffed as the victim.

  2. Duloxetine-related panic attacks.

    PubMed

    Sabljić, Vladimir; Rakun, Radmir; Ružić, Klementina; Grahovac, Tanja

    2011-03-01

    Side-effects arising on the grounds of antidepressant administration pose as a substantial obstacle hindering successful depressive disorder treatment. Side-effects, especially those severe or those manifested through dramatic clinical presentations such as panic attacks, make the treatment far more difficult and shake patients' trust in both the treatment and the treating physician. This case report deals with a patient experiencing a moderately severe depressive episode, who responded to duloxetine treatment administered in the initial dose of 30 mg per day with as many as three panic attacks in two days. Upon duloxetine withdrawal, these panic attacks ceased as well. The patient continued tianeptine and alprazolam treatment during which no significant side-effects had been seen, so that she gradually recovered. Some of the available literature sources have suggested the possibility of duloxetine administration to the end of generalised anxiety disorder and panic attack treatment. However, they are outnumbered by the contributions reporting about duloxetine-related anxiety, aggressiveness and panic attacks. In line with the foregoing, further monitoring of each and every duloxetine-administered patient group needs to be pursued so as to be able to evaluate treatment benefits and weigh them against risks of anxiety or panic attack onset.

  3. Analytical Characterization of Internet Security Attacks

    ERIC Educational Resources Information Center

    Sellke, Sarah H.

    2010-01-01

    Internet security attacks have drawn significant attention due to their enormously adverse impact. These attacks includes Malware (Viruses, Worms, Trojan Horse), Denial of Service, Packet Sniffer, and Password Attacks. There is an increasing need to provide adequate defense mechanisms against these attacks. My thesis proposal deals with analytical…

  4. Eyespots divert attacks by fish.

    PubMed

    Kjernsmo, Karin; Merilaita, Sami

    2013-09-01

    Eyespots (colour patterns consisting of concentric rings) are found in a wide range of animal taxa and are often assumed to have an anti-predator function. Previous experiments have found strong evidence for an intimidating effect of eyespots against passerine birds. Some eyespots have been suggested to increase prey survival by diverting attacks towards less vital body parts or a direction that would facilitate escape. While eyespots in aquatic environments are widespread, their function is extremely understudied. Therefore, we investigated the protective function of eyespots against attacking fish. We used artificial prey and predator-naive three-spined sticklebacks (Gasterosteus aculeatus) as predators to test both the diversion (deflection) and the intimidation hypothesis. Interestingly, our results showed that eyespots smaller than the fish' own eye very effectively draw the attacks of the fish towards them. Furthermore, our experiment also showed that this was not due to the conspicuousness of the eyespot, because attack latency did not differ between prey items with and without eyespots. We found little support for an intimidating effect by larger eyespots. Even though also other markings might misdirect attacks, we can conclude that the misdirecting function may have played an important role in the evolution of eyespots in aquatic environments. PMID:23864602

  5. Eyespots divert attacks by fish

    PubMed Central

    Kjernsmo, Karin; Merilaita, Sami

    2013-01-01

    Eyespots (colour patterns consisting of concentric rings) are found in a wide range of animal taxa and are often assumed to have an anti-predator function. Previous experiments have found strong evidence for an intimidating effect of eyespots against passerine birds. Some eyespots have been suggested to increase prey survival by diverting attacks towards less vital body parts or a direction that would facilitate escape. While eyespots in aquatic environments are widespread, their function is extremely understudied. Therefore, we investigated the protective function of eyespots against attacking fish. We used artificial prey and predator-naive three-spined sticklebacks (Gasterosteus aculeatus) as predators to test both the diversion (deflection) and the intimidation hypothesis. Interestingly, our results showed that eyespots smaller than the fish’ own eye very effectively draw the attacks of the fish towards them. Furthermore, our experiment also showed that this was not due to the conspicuousness of the eyespot, because attack latency did not differ between prey items with and without eyespots. We found little support for an intimidating effect by larger eyespots. Even though also other markings might misdirect attacks, we can conclude that the misdirecting function may have played an important role in the evolution of eyespots in aquatic environments. PMID:23864602

  6. Eyespots divert attacks by fish.

    PubMed

    Kjernsmo, Karin; Merilaita, Sami

    2013-09-01

    Eyespots (colour patterns consisting of concentric rings) are found in a wide range of animal taxa and are often assumed to have an anti-predator function. Previous experiments have found strong evidence for an intimidating effect of eyespots against passerine birds. Some eyespots have been suggested to increase prey survival by diverting attacks towards less vital body parts or a direction that would facilitate escape. While eyespots in aquatic environments are widespread, their function is extremely understudied. Therefore, we investigated the protective function of eyespots against attacking fish. We used artificial prey and predator-naive three-spined sticklebacks (Gasterosteus aculeatus) as predators to test both the diversion (deflection) and the intimidation hypothesis. Interestingly, our results showed that eyespots smaller than the fish' own eye very effectively draw the attacks of the fish towards them. Furthermore, our experiment also showed that this was not due to the conspicuousness of the eyespot, because attack latency did not differ between prey items with and without eyespots. We found little support for an intimidating effect by larger eyespots. Even though also other markings might misdirect attacks, we can conclude that the misdirecting function may have played an important role in the evolution of eyespots in aquatic environments.

  7. Evaluation of Word Attack Skills.

    ERIC Educational Resources Information Center

    Follettie, Joseph F.

    A framework for more apt and sensitive evaluation of generalized word attack skill--the heart of oral reading skill--is presented. The paper envisions the design and development of oral reading instruction as bounded by a fully-specified evaluation scheme. (Author)

  8. Detection of complex cyber attacks

    NASA Astrophysics Data System (ADS)

    Gregorio-de Souza, Ian; Berk, Vincent H.; Giani, Annarita; Bakos, George; Bates, Marion; Cybenko, George; Madory, Doug

    2006-05-01

    One significant drawback to currently available security products is their inabilty to correlate diverse sensor input. For instance, by only using network intrusion detection data, a root kit installed through a weak username-password combination may go unnoticed. Similarly, an administrator may never make the link between deteriorating response times from the database server and an attacker exfiltrating trusted data, if these facts aren't presented together. Current Security Information Management Systems (SIMS) can collect and represent diverse data but lack sufficient correlation algorithms. By using a Process Query System, we were able to quickly bring together data flowing from many sources, including NIDS, HIDS, server logs, CPU load and memory usage, etc. We constructed PQS models that describe dynamic behavior of complicated attacks and failures, allowing us to detect and differentiate simultaneous sophisticated attacks on a target network. In this paper, we discuss the benefits of implementing such a multistage cyber attack detection system using PQS. We focus on how data from multiple sources can be combined and used to detect and track comprehensive network security events that go unnoticed using conventional tools.

  9. Terrorist attacks escalate in frequency and fatalities preceding highly lethal attacks.

    PubMed

    Martens, Andy; Sainudiin, Raazesh; Sibley, Chris G; Schimel, Jeff; Webber, David

    2014-01-01

    Highly lethal terrorist attacks, which we define as those killing 21 or more people, account for 50% of the total number of people killed in all terrorist attacks combined, yet comprise only 3.5% of terrorist attacks. Given the disproportionate influence of these incidents, uncovering systematic patterns in attacks that precede and anticipate these highly lethal attacks may be of value for understanding attacks that exact a heavy toll on life. Here we examined whether the activity of terrorist groups escalates--both in the number of people killed per attack and in the frequency of attacks--leading up to highly lethal attacks. Analyses of terrorist attacks drawn from a state-of-the-art international terrorism database (The Global Terrorism Database) showed evidence for both types of escalation leading up to highly lethal attacks, though complexities to the patterns emerged as well. These patterns of escalation do not emerge among terrorist groups that never commit a highly lethal attack.

  10. Attack Vulnerability of Network Controllability

    PubMed Central

    2016-01-01

    Controllability of complex networks has attracted much attention, and understanding the robustness of network controllability against potential attacks and failures is of practical significance. In this paper, we systematically investigate the attack vulnerability of network controllability for the canonical model networks as well as the real-world networks subject to attacks on nodes and edges. The attack strategies are selected based on degree and betweenness centralities calculated for either the initial network or the current network during the removal, among which random failure is as a comparison. It is found that the node-based strategies are often more harmful to the network controllability than the edge-based ones, and so are the recalculated strategies than their counterparts. The Barabási-Albert scale-free model, which has a highly biased structure, proves to be the most vulnerable of the tested model networks. In contrast, the Erdős-Rényi random model, which lacks structural bias, exhibits much better robustness to both node-based and edge-based attacks. We also survey the control robustness of 25 real-world networks, and the numerical results show that most real networks are control robust to random node failures, which has not been observed in the model networks. And the recalculated betweenness-based strategy is the most efficient way to harm the controllability of real-world networks. Besides, we find that the edge degree is not a good quantity to measure the importance of an edge in terms of network controllability. PMID:27588941

  11. Attack Vulnerability of Network Controllability.

    PubMed

    Lu, Zhe-Ming; Li, Xin-Feng

    2016-01-01

    Controllability of complex networks has attracted much attention, and understanding the robustness of network controllability against potential attacks and failures is of practical significance. In this paper, we systematically investigate the attack vulnerability of network controllability for the canonical model networks as well as the real-world networks subject to attacks on nodes and edges. The attack strategies are selected based on degree and betweenness centralities calculated for either the initial network or the current network during the removal, among which random failure is as a comparison. It is found that the node-based strategies are often more harmful to the network controllability than the edge-based ones, and so are the recalculated strategies than their counterparts. The Barabási-Albert scale-free model, which has a highly biased structure, proves to be the most vulnerable of the tested model networks. In contrast, the Erdős-Rényi random model, which lacks structural bias, exhibits much better robustness to both node-based and edge-based attacks. We also survey the control robustness of 25 real-world networks, and the numerical results show that most real networks are control robust to random node failures, which has not been observed in the model networks. And the recalculated betweenness-based strategy is the most efficient way to harm the controllability of real-world networks. Besides, we find that the edge degree is not a good quantity to measure the importance of an edge in terms of network controllability. PMID:27588941

  12. Generic attack approaches for industrial control systems.

    SciTech Connect

    Duggan, David P.

    2006-01-01

    This report suggests a generic set of attack approaches that are expected to be used against Industrial Control Systems that have been built according to a specific reference model for control systems. The posed attack approaches are ordered by the most desirable, based upon the goal of an attacker. Each attack approach is then graded by the category of adversary that would be capable of utilizing that attack approach. The goal of this report is to identify necessary levels of security required to prevent certain types of attacks against Industrial Control Systems.

  13. Diabetes Ups Risk of Heart Attack Death

    MedlinePlus

    ... news/fullstory_159557.html Diabetes Ups Risk of Heart Attack Death Study points to need for better coordinated ... are much more likely to die after a heart attack than people without the blood sugar condition, a ...

  14. Being active after a heart attack (image)

    MedlinePlus

    ... best activity when you start exercising after a heart attack. Start slowly, and increase the amount of time ... best activity when you start exercising after a heart attack. Start slowly, and increase the amount of time ...

  15. Biomechanics of knife stab attacks.

    PubMed

    Chadwick, E K; Nicol, A C; Lane, J V; Gray, T G

    1999-10-25

    Equipment, materials and methods for the measurement of the biomechanical parameters governing knife stab attacks have been developed and data have been presented that are relevant to the improvement of standards for the testing of stab-resistant materials. A six-camera Vicon motion analysis system was used to measure velocity, and derive energy and momentum during the approach phase of the attack and a specially developed force-measuring knife was used to measure three-dimensional forces and torque during the impact phase. The body segments associated with the knife were modelled as a series of rigid segments: trunk, upper arm, forearm and hand. The velocities of these segments, together with knowledge of the mass distribution from biomechanical tables, allowed the calculation of the individual segment energy and momentum values. The instrumented knife measured four components of load: axial force (along the length of the blade), cutting force (parallel to the breadth of the blade), lateral force (across the blade) and torque (twisting action) using foil strain gauges. Twenty volunteers were asked to stab a target with near maximal effort. Three styles of stab were used: a short thrust forward, a horizontal style sweep around the body and an overhand stab. These styles were chosen based on reported incidents, providing more realistic data than had previously existed. The 95th percentile values for axial force and energy were 1885 N and 69 J, respectively. The ability of current test methods to reproduce the mechanical parameters measured in human stab attacks has been assessed. It was found that current test methods could reproduce the range of energy and force values measured in the human stab attacks, although the simulation was not accurate in some respects. Non-axial force and torque values were also found to be significant in the human tests, but these are not reproduced in the standard mechanical tests.

  16. On Mitigating Distributed Denial of Service Attacks

    ERIC Educational Resources Information Center

    Gao, Zhiqiang

    2006-01-01

    Denial of service (DoS) attacks and distributed denial of service (DDoS) attacks are probably the most ferocious threats in the Internet, resulting in tremendous economic and social implications/impacts on our daily lives that are increasingly depending on the well-being of the Internet. How to mitigate these attacks effectively and efficiently…

  17. Cyberprints: Identifying Cyber Attackers by Feature Analysis

    ERIC Educational Resources Information Center

    Blakely, Benjamin A.

    2012-01-01

    The problem of attributing cyber attacks is one of increasing importance. Without a solid method of demonstrating the origin of a cyber attack, any attempts to deter would-be cyber attackers are wasted. Existing methods of attribution make unfounded assumptions about the environment in which they will operate: omniscience (the ability to gather,…

  18. Current characteristics associated with hereditary angioedema attacks and treatment: the home infusion based patient experience.

    PubMed

    Tachdjian, Raffi; Banerji, Aleena; Guyer, Autumn; Morphew, Tricia

    2015-01-01

    This article presents a current perspective on the characteristics of hereditary angioedema (HAE) attacks and treatment as captured by a home infusion service. Retrospective data on 158 HAE patients who were enrolled in this acute treatment program were analyzed for factors surrounding an attack. The majority of patients had a high level of disease severity at baseline (88%), with a higher than expected likelihood of having a positive family history (87.8%). The most likely times for patients to call for home treatment were just before and during working hours (6:00 A.M.-5:00 P.M.). Eighty-three percent had more than one alternate mode of medication. Factors associated with a severe attack included an overall severe rating of HAE attacks in the previous year, an abdominal attack alone or a combination of peripheral and abdominal attacks versus a peripheral attack alone, and the use of two doses rather than one for treatment of the current attack. Average time to relief onset was 43.5 minutes. One dose of ecallantide was sufficient to treat the majority of attacks, and a second dose was needed in 23.6% of patients experiencing a severe attack. However, patients who reported both a severe attack rating during the previous year and experiencing only a peripheral current attack were more likely to experience a severe current attack. Acute treatment paradigms for HAE remain diverse. Understanding factors driving these decisions could help alleviate the overall burden of this disease and help overcome some of the challenges faced by the patients and their caretakers and improve their quality of life. Enhanced capture and analysis of prodromal factors in future studies should help us further alleviate the burden of this disease.

  19. Marr's Attacks: On Reductionism and Vagueness.

    PubMed

    Eliasmith, Chris; Kolbeck, Carter

    2015-04-01

    It has been suggested that Marr took the three levels he famously identifies to be independent. In this paper, we argue that Marr's view is more nuanced. Specifically, we show that the view explicitly articulated in his work attempts to integrate the levels, and in doing so results in Marr attacking both reductionism and vagueness. The result is a perspective in which both high-level information-processing constraints and low-level implementational constraints play mutually reinforcing and constraining roles. We discuss our recent work on Spaun-currently the world's largest functional brain model-that demonstrates the positive impact of this kind of unifying integration of Marr's levels. We argue that this kind of integration avoids his concerns with both reductionism and vagueness. In short, we suggest that the methods behind Spaun can be used to satisfy Marr's explicit interest in combining high-level functional and detailed mechanistic explanations.

  20. Ballistic Beloniformes attacking through Snell's Window.

    PubMed

    Day, R D; Mueller, F; Carseldine, L; Meyers-Cherry, N; Tibbetts, I R

    2016-02-01

    Needlefishes (Beloniformes) were observed employing a range of stalking and attacking behaviours to attack schools of bait fishes ranging from the use of tactics common to predatory fishes to a novel behaviour: the use of leaping, aerial attacks. These aerial attacks are suggested to serve two purposes: to extend the attack range of the needlefishes and to reduce their prey's potential for evasion. Furthermore, a third purpose is hypothesized that the needlefishes are taking advantage of Snell's Window, an optical effect which may mask their approach to their prey.

  1. Lightweight Distance Bounding Protocol against Relay Attacks

    NASA Astrophysics Data System (ADS)

    Kim, Jin Seok; Cho, Kookrae; Yum, Dae Hyun; Hong, Sung Je; Lee, Pil Joong

    Traditional authentication protocols are based on cryptographic techniques to achieve identity verification. Distance bounding protocols are an enhanced type of authentication protocol built upon both signal traversal time measurement and cryptographic techniques to accomplish distance verification as well as identity verification. A distance bounding protocol is usually designed to defend against the relay attack and the distance fraud attack. As there are applications to which the distance fraud attack is not a serious threat, we propose a streamlined distance bounding protocol that focuses on the relay attack. The proposed protocol is more efficient than previous protocols and has a low false acceptance rate under the relay attack.

  2. Preparedness for an anthrax attack.

    PubMed

    Franz, David R

    2009-12-01

    Bacillus anthracis is a long-known bacterial organism with a uniquely stable spore stage. Its stability and the lethal disease which results when the spore is inhaled made it a favorite of state-sponsored biological weapons programs throughout the Cold War era. It is also believed to be high on the list of candidate microbial agents which could be used by terrorist groups or lone actors. Its unique characteristics make protection of humans, especially civilians, from an intentional biological attack very difficult. The author argues that an all-hazards/public health approach - which would also be needed for any natural or deliberate outbreak, no matter the agent - should serve as a foundation of preparation for the specific anthrax countermeasures. Because B. anthracis is a unique organism, specific countermeasures for anthrax detection, diagnostics, prophylaxis and therapy, should be developed in nations or regions where the threat of biological attack is believed to warrant such preparation. Other considerations for a nation interested in anthrax preparedness are discussed.

  3. Shoulder injuries from attacking motion

    NASA Astrophysics Data System (ADS)

    Yanagi, Shigeru; Nishimura, Tetsu; Itoh, Masaru; Wada, Yuhei; Watanabe, Naoki

    1997-03-01

    Sports injuries have bothered professional players. Although many medical doctors try to treat injured players, to prevent sports injuries is more important. Hence, it is required to clear a kinematic mechanism of the sport injuries. A shoulder of volleyball attacker or baseball pitcher is often inured by playing motion. The injuries are mainly caused at the end of long head tendon, which is located in the upper side of scapula. Generally, a muscle and tendon have enough strength against tensile force, however, it seems that they are sometimes defeated by the lateral force. It is imagined that the effect of the lateral force has a possibility of injuring the tendon. If we find the influence of the lateral force on the injured portion, the mechanism of injuries must be cleared. In our research, volleyball attacking motion is taken by high speed video cameras. We analyze the motion as links system and obtain an acceleration of an arm and a shoulder from video image data. The generated force at a shoulder joint is calculated and resolved into the lateral and longitudinal forces. Our final goal is to discuss a possibility that the lateral force causes the injuries.

  4. Migraine attacks the Basal Ganglia

    PubMed Central

    2011-01-01

    Background With time, episodes of migraine headache afflict patients with increased frequency, longer duration and more intense pain. While episodic migraine may be defined as 1-14 attacks per month, there are no clear-cut phases defined, and those patients with low frequency may progress to high frequency episodic migraine and the latter may progress into chronic daily headache (> 15 attacks per month). The pathophysiology of this progression is completely unknown. Attempting to unravel this phenomenon, we used high field (human) brain imaging to compare functional responses, functional connectivity and brain morphology in patients whose migraine episodes did not progress (LF) to a matched (gender, age, age of onset and type of medication) group of patients whose migraine episodes progressed (HF). Results In comparison to LF patients, responses to pain in HF patients were significantly lower in the caudate, putamen and pallidum. Paradoxically, associated with these lower responses in HF patients, gray matter volume of the right and left caudate nuclei were significantly larger than in the LF patients. Functional connectivity analysis revealed additional differences between the two groups in regard to response to pain. Conclusions Supported by current understanding of basal ganglia role in pain processing, the findings suggest a significant role of the basal ganglia in the pathophysiology of the episodic migraine. PMID:21936901

  5. Preparedness for an anthrax attack.

    PubMed

    Franz, David R

    2009-12-01

    Bacillus anthracis is a long-known bacterial organism with a uniquely stable spore stage. Its stability and the lethal disease which results when the spore is inhaled made it a favorite of state-sponsored biological weapons programs throughout the Cold War era. It is also believed to be high on the list of candidate microbial agents which could be used by terrorist groups or lone actors. Its unique characteristics make protection of humans, especially civilians, from an intentional biological attack very difficult. The author argues that an all-hazards/public health approach - which would also be needed for any natural or deliberate outbreak, no matter the agent - should serve as a foundation of preparation for the specific anthrax countermeasures. Because B. anthracis is a unique organism, specific countermeasures for anthrax detection, diagnostics, prophylaxis and therapy, should be developed in nations or regions where the threat of biological attack is believed to warrant such preparation. Other considerations for a nation interested in anthrax preparedness are discussed. PMID:19619577

  6. VoIP attacks detection engine based on neural network

    NASA Astrophysics Data System (ADS)

    Safarik, Jakub; Slachta, Jiri

    2015-05-01

    The security is crucial for any system nowadays, especially communications. One of the most successful protocols in the field of communication over IP networks is Session Initiation Protocol. It is an open-source project used by different kinds of applications, both open-source and proprietary. High penetration and text-based principle made SIP number one target in IP telephony infrastructure, so security of SIP server is essential. To keep up with hackers and to detect potential malicious attacks, security administrator needs to monitor and evaluate SIP traffic in the network. But monitoring and following evaluation could easily overwhelm the security administrator in networks, typically in networks with a number of SIP servers, users and logically or geographically separated networks. The proposed solution lies in automatic attack detection systems. The article covers detection of VoIP attacks through a distributed network of nodes. Then the gathered data analyze aggregation server with artificial neural network. Artificial neural network means multilayer perceptron network trained with a set of collected attacks. Attack data could also be preprocessed and verified with a self-organizing map. The source data is detected by distributed network of detection nodes. Each node contains a honeypot application and traffic monitoring mechanism. Aggregation of data from each node creates an input for neural networks. The automatic classification on a centralized server with low false positive detection reduce the cost of attack detection resources. The detection system uses modular design for easy deployment in final infrastructure. The centralized server collects and process detected traffic. It also maintains all detection nodes.

  7. Defending networks against denial-of-service attacks

    NASA Astrophysics Data System (ADS)

    Gelenbe, Erol; Gellman, Michael; Loukas, George

    2004-11-01

    Denial of service attacks, viruses and worms are common tools for malicious adversarial behavior in networks. Experience shows that over the last few years several of these techniques have probably been used by governments to impair the Internet communications of various entities, and we can expect that these and other information warfare tools will be used increasingly as part of hostile behavior either independently, or in conjunction with other forms of attack in conventional or asymmetric warfare, as well as in other forms of malicious behavior. In this paper we concentrate on Distributed Denial of Service Attacks (DDoS) where one or more attackers generate flooding traffic and direct it from multiple sources towards a set of selected nodes or IP addresses in the Internet. We first briefly survey the literature on the subject, and discuss some examples of DDoS incidents. We then present a technique that can be used for DDoS protection based on creating islands of protection around a critical information infrastructure. This technique, that we call the CPN-DoS-DT (Cognitive Packet Networks DoS Defence Technique), creates a self-monitoring sub-network surrounding each critical infrastructure node. CPN-DoS-DT is triggered by a DDoS detection scheme, and generates control traffic from the objects of the DDoS attack to the islands of protection where DDOS packet flows are destroyed before they reach the critical infrastructure. We use mathematical modelling, simulation and experiments on our test-bed to show the positive and negative outcomes that may result from both the attack, and the CPN-DoS-DT protection mechanism, due to imperfect detection and false alarms.

  8. Percolation of localized attack on complex networks

    NASA Astrophysics Data System (ADS)

    Shao, Shuai; Huang, Xuqing; Stanley, H. Eugene; Havlin, Shlomo

    2015-02-01

    The robustness of complex networks against node failure and malicious attack has been of interest for decades, while most of the research has focused on random attack or hub-targeted attack. In many real-world scenarios, however, attacks are neither random nor hub-targeted, but localized, where a group of neighboring nodes in a network are attacked and fail. In this paper we develop a percolation framework to analytically and numerically study the robustness of complex networks against such localized attack. In particular, we investigate this robustness in Erdős-Rényi networks, random-regular networks, and scale-free networks. Our results provide insight into how to better protect networks, enhance cybersecurity, and facilitate the design of more robust infrastructures.

  9. 'Crescendo' transient ischemic attacks: clinical and angiographic correlations.

    PubMed

    Rothrock, J F; Lyden, P D; Yee, J; Wiederholt, W C

    1988-02-01

    Forty-seven consecutive patients presenting acutely with repetitive symptoms indicative of anterior circulation ischemia ("crescendo" transient ischemic attacks) were evaluated to identify clinical features that might reliably predict the presence of significant stenosis, ulceration, or both in the presumably symptomatic internal carotid artery. Angiographic or intraoperative correlation was obtained in all patients, and 26 (55%) were found to have anatomically significant disease. Of 20 patients with signs or symptoms suggestive of cortical ischemia, amaurosis fugax, or both, 17 (85%) had "positive" angiograms; of 18 with numbness/weakness only, 9 (50%) had positive angiograms; of 9 whose symptoms suggested lacunar ischemia, none had positive angiograms.

  10. Low Heat Pain Thresholds in Migraineurs Between Attacks

    PubMed Central

    Schwedt, Todd J.; Zuniga, Leslie; Chong, Catherine D.

    2014-01-01

    Background/Objective Between attacks, migraine is associated with hypersensitivities to sensory stimuli. The objective of this study was to investigate hypersensitivity to pain in migraineurs between attacks. Methods Cutaneous heat pain thresholds were measured in 112 migraineurs, migraine free for ≥48 hours, and 75 healthy controls. Pain thresholds at the head and at the arm were compared between migraineurs and controls using two-tailed t-tests. Amongst migraineurs, correlations between heat pain thresholds and headache frequency, allodynia symptom severity, and time interval until next headache were calculated. Results Migraineurs had lower pain thresholds than controls at the head (43.9°C+/−3.2°C vs. 45.1°C+/−3.0°C, p=.015) and arm (43.2°C+/−3.4°C vs. 44.8°C+/−3.3°C, p<0.001). There were not significant correlations between pain thresholds and headache frequency or allodynia symptom severity. For the 41 migraineurs for whom time to next headache was known, there were positive correlations between time to next headache and pain thresholds at the head (r=.352, p=.024) and arm (r=.312, p=.047). Conclusions This study provides evidence that migraineurs have low heat pain thresholds between migraine attacks. Mechanisms underlying these lower pain thresholds could also predispose the migraineur to their next migraine attack, a hypothesis supported by finding positive correlations between pain thresholds and time to next migraine attack. PMID:25246520

  11. "Homicide by heart attack" revisited.

    PubMed

    Turner, Staci A; Barnard, Jeffrey J; Spotswood, Sheila D; Prahlow, Joseph A

    2004-05-01

    The sudden death of a person caused by an arrhythmia that is induced by physical and/or emotional stress provoked by the criminal activity of another person is sometimes referred to as "homicide by heart attack." Published criteria for such an event relate to situations where no physical contact occurs between the perpetrator and the victim. Situations involving physical contact, but with absence of lethal injuries, are frequently treated is a similar fashion by forensic pathologists. Herein, we propose a set of modified criteria, which include cases where physical contact has occurred. Five examples of so-called "homicide by heart attack" are presented, including a 40-year-old man who was struck in the head with a wooden statue, a 74-year-old man who was punched in the jaw by a robber, a 66-year-old woman who was started awake by a home-intruder, a 67-year-old woman who struggled with a would-be purse-snatcher in a parking lot, and a 52-year-old man who was in a physical altercation with a younger man. In each instance, autopsy revealed the presence of severe, underlying heart disease, as well as absence of lethal injuries. In each case, investigative information was such that the emotional and/or physical stress associated with the criminal activity of another individual was deemed contributory to the death. The presumed mechanism of death in each case was a cardiac dysrhythmia related to underlying heart disease, but initiated by the emotional and/or physical stress.

  12. A simple public-key attack on phase-truncation-based double-images encryption system

    NASA Astrophysics Data System (ADS)

    Ding, Xiangling; Yang, Gaobo; He, Dajiang

    2015-07-01

    Phase-truncation based double-images cryptosystem can avoid the iterative Fourier transforms and realize double-images encryption. In this paper, a simple public-key attack is proposed to break this cryptosystem by using arbitrary position parameters and three public keys. The attack process is composed of two steps. Firstly, the decryption keys are simply generated with the help of arbitrary position parameters and the three public keys. Secondly, the two approximate values of the original images are obtained by using the generated decryption keys. Moreover, the proposed public-key attack is different from the existing attacks. It is not sensitive to position parameters of the double-images and the computing efficiency is also much better. Computer simulation results further prove its vulnerability.

  13. Cued Panic Attacks in Body Dysmorphic Disorder

    PubMed Central

    Phillips, Katharine A.; Menard, William; Bjornsson, Andri S.

    2013-01-01

    Background Body dysmorphic disorder (BDD) is a common and often severe disorder. Clinical observations suggest that panic attacks triggered by BDD symptoms may be common. However, to our knowledge, no study has examined such panic attacks in BDD. We investigated the prevalence, clinical features, and correlates of BDD-triggered panic attacks in individuals with this disorder. Methods Panic attacks and other variables were assessed using reliable and valid measures in 76 individuals with lifetime DSM-IV BDD. Results 28.9% (95% CI, 18.5%–39.4%) of participants reported lifetime panic attacks triggered by BDD symptoms. The most common triggers of such attacks were feeling that others were looking at or scrutinizing the perceived appearance defects (61.9%), looking in the mirror at perceived defects (38.1%), and being in bright light where perceived defects would be more visible (23.8%). The most common panic attack symptoms were palpitations (86.4%), sweating (66.7%), shortness of breath (63.6%), trembling or shaking (63.6%), and fear of losing control or going crazy (63.6%). Compared to participants without such panic attacks, those with BDD-triggered panic attacks had more severe lifetime BDD, social anxiety, and depressive symptoms, as well as poorer functioning and quality of life on a number of measures. They were also less likely to be employed and more likely to have been psychiatrically hospitalized and to have had suicidal ideation due to BDD. Conclusions Panic attacks triggered by BDD-related situations appear common in individuals with this disorder. BDD-triggered panic attacks were associated with greater symptom severity and morbidity. PMID:23653076

  14. Phase-remapping attack in practical quantum-key-distribution systems

    SciTech Connect

    Fung, Chi-Hang Fred; Qi, Bing; Lo, Hoi-Kwong; Tamaki, Kiyoshi

    2007-03-15

    Quantum key distribution (QKD) can be used to generate secret keys between two distant parties. Even though QKD has been proven unconditionally secure against eavesdroppers with unlimited computation power, practical implementations of QKD may contain loopholes that may lead to the generated secret keys being compromised. In this paper, we propose a phase-remapping attack targeting two practical bidirectional QKD systems (the 'plug-and-play' system and the Sagnac system). We showed that if the users of the systems are unaware of our attack, the final key shared between them can be compromised in some situations. Specifically, we showed that, in the case of the Bennett-Brassard 1984 (BB84) protocol with ideal single-photon sources, when the quantum bit error rate (QBER) is between 14.6% and 20%, our attack renders the final key insecure, whereas the same range of QBER values has been proved secure if the two users are unaware of our attack; also, we demonstrated three situations with realistic devices where positive key rates are obtained without the consideration of Trojan horse attacks but in fact no key can be distilled. We remark that our attack is feasible with only current technology. Therefore, it is very important to be aware of our attack in order to ensure absolute security. In finding our attack, we minimize the QBER over individual measurements described by a general POVM, which has some similarity with the standard quantum state discrimination problem.

  15. Detecting and Preventing Sybil Attacks in Wireless Sensor Networks Using Message Authentication and Passing Method.

    PubMed

    Dhamodharan, Udaya Suriya Raj Kumar; Vayanaperumal, Rajamani

    2015-01-01

    Wireless sensor networks are highly indispensable for securing network protection. Highly critical attacks of various kinds have been documented in wireless sensor network till now by many researchers. The Sybil attack is a massive destructive attack against the sensor network where numerous genuine identities with forged identities are used for getting an illegal entry into a network. Discerning the Sybil attack, sinkhole, and wormhole attack while multicasting is a tremendous job in wireless sensor network. Basically a Sybil attack means a node which pretends its identity to other nodes. Communication to an illegal node results in data loss and becomes dangerous in the network. The existing method Random Password Comparison has only a scheme which just verifies the node identities by analyzing the neighbors. A survey was done on a Sybil attack with the objective of resolving this problem. The survey has proposed a combined CAM-PVM (compare and match-position verification method) with MAP (message authentication and passing) for detecting, eliminating, and eventually preventing the entry of Sybil nodes in the network. We propose a scheme of assuring security for wireless sensor network, to deal with attacks of these kinds in unicasting and multicasting.

  16. Detecting and Preventing Sybil Attacks in Wireless Sensor Networks Using Message Authentication and Passing Method

    PubMed Central

    Dhamodharan, Udaya Suriya Raj Kumar; Vayanaperumal, Rajamani

    2015-01-01

    Wireless sensor networks are highly indispensable for securing network protection. Highly critical attacks of various kinds have been documented in wireless sensor network till now by many researchers. The Sybil attack is a massive destructive attack against the sensor network where numerous genuine identities with forged identities are used for getting an illegal entry into a network. Discerning the Sybil attack, sinkhole, and wormhole attack while multicasting is a tremendous job in wireless sensor network. Basically a Sybil attack means a node which pretends its identity to other nodes. Communication to an illegal node results in data loss and becomes dangerous in the network. The existing method Random Password Comparison has only a scheme which just verifies the node identities by analyzing the neighbors. A survey was done on a Sybil attack with the objective of resolving this problem. The survey has proposed a combined CAM-PVM (compare and match-position verification method) with MAP (message authentication and passing) for detecting, eliminating, and eventually preventing the entry of Sybil nodes in the network. We propose a scheme of assuring security for wireless sensor network, to deal with attacks of these kinds in unicasting and multicasting. PMID:26236773

  17. The cost of attack in competing networks.

    PubMed

    Podobnik, B; Horvatic, D; Lipic, T; Perc, M; Buldú, J M; Stanley, H E

    2015-11-01

    Real-world attacks can be interpreted as the result of competitive interactions between networks, ranging from predator-prey networks to networks of countries under economic sanctions. Although the purpose of an attack is to damage a target network, it also curtails the ability of the attacker, which must choose the duration and magnitude of an attack to avoid negative impacts on its own functioning. Nevertheless, despite the large number of studies on interconnected networks, the consequences of initiating an attack have never been studied. Here, we address this issue by introducing a model of network competition where a resilient network is willing to partially weaken its own resilience in order to more severely damage a less resilient competitor. The attacking network can take over the competitor's nodes after their long inactivity. However, owing to a feedback mechanism the takeovers weaken the resilience of the attacking network. We define a conservation law that relates the feedback mechanism to the resilience dynamics for two competing networks. Within this formalism, we determine the cost and optimal duration of an attack, allowing a network to evaluate the risk of initiating hostilities. PMID:26490628

  18. 47 CFR 76.1612 - Personal attack.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Personal attack. 76.1612 Section 76.1612 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Notices § 76.1612 Personal attack. (a) When, during origination cablecasting...

  19. Combating Memory Corruption Attacks On Scada Devices

    NASA Astrophysics Data System (ADS)

    Bellettini, Carlo; Rrushi, Julian

    Memory corruption attacks on SCADA devices can cause significant disruptions to control systems and the industrial processes they operate. However, despite the presence of numerous memory corruption vulnerabilities, few, if any, techniques have been proposed for addressing the vulnerabilities or for combating memory corruption attacks. This paper describes a technique for defending against memory corruption attacks by enforcing logical boundaries between potentially hostile data and safe data in protected processes. The technique encrypts all input data using random keys; the encrypted data is stored in main memory and is decrypted according to the principle of least privilege just before it is processed by the CPU. The defensive technique affects the precision with which attackers can corrupt control data and pure data, protecting against code injection and arc injection attacks, and alleviating problems posed by the incomparability of mitigation techniques. An experimental evaluation involving the popular Modbus protocol demonstrates the feasibility and efficiency of the defensive technique.

  20. An Network Attack Modeling Method Based on MLL-AT

    NASA Astrophysics Data System (ADS)

    Fen, Yan; Xinchun, Yin; Hao, Huang

    In this paper, the method of modeling attack using attack tree is researched. The main goal is effectively using attack tree to model and express multi-stage network attacks. We expand and improve the traditional attack tree. The attack nodes in traditional attack tree are redefined, and the attack risk of leaf node is quantified. On those basis, the mentality and method of building MLL-AT (Multi-Level & Layer Attack Tree) are proposed. The improved attack tree can model attack more accurately, in particular to multi-stage network attacks. And the new model can also be used to evaluate system's risk, to distinguish between varying system security threat degrees caused by different attack sequences.

  1. Terrorist Attacks Escalate in Frequency and Fatalities Preceding Highly Lethal Attacks

    PubMed Central

    Martens, Andy; Sainudiin, Raazesh; Sibley, Chris G.; Schimel, Jeff; Webber, David

    2014-01-01

    Highly lethal terrorist attacks, which we define as those killing 21 or more people, account for 50% of the total number of people killed in all terrorist attacks combined, yet comprise only 3.5% of terrorist attacks. Given the disproportionate influence of these incidents, uncovering systematic patterns in attacks that precede and anticipate these highly lethal attacks may be of value for understanding attacks that exact a heavy toll on life. Here we examined whether the activity of terrorist groups escalates–both in the number of people killed per attack and in the frequency of attacks–leading up to highly lethal attacks. Analyses of terrorist attacks drawn from a state-of-the-art international terrorism database (The Global Terrorism Database) showed evidence for both types of escalation leading up to highly lethal attacks, though complexities to the patterns emerged as well. These patterns of escalation do not emerge among terrorist groups that never commit a highly lethal attack. PMID:24755753

  2. Hill-Climbing Attacks and Robust Online Signature Verification Algorithm against Hill-Climbing Attacks

    NASA Astrophysics Data System (ADS)

    Muramatsu, Daigo

    Attacks using hill-climbing methods have been reported as a vulnerability of biometric authentication systems. In this paper, we propose a robust online signature verification algorithm against such attacks. Specifically, the attack considered in this paper is a hill-climbing forged data attack. Artificial forgeries are generated offline by using the hill-climbing method, and the forgeries are input to a target system to be attacked. In this paper, we analyze the menace of hill-climbing forged data attacks using six types of hill-climbing forged data and propose a robust algorithm by incorporating the hill-climbing method into an online signature verification algorithm. Experiments to evaluate the proposed system were performed using a public online signature database. The proposed algorithm showed improved performance against this kind of attack.

  3. Attack detection in unattended sensor networks

    NASA Astrophysics Data System (ADS)

    Wu, Curt; Monnier, Camille; Fry, Gerald; Girod, Lewis; Luke, Jahn

    2010-04-01

    Because sensor networks are often deployed in hostile environments where their security and integrity may be compromised, it is essential to maximize the reliability and trustworthiness of existing and envisioned sensor networks. During operations, the sensor network must be robust to deception, node compromise, and various other attacks, while maintaining the operator's situational awareness regarding the health and integrity of the system. To address these needs, we have designed a Framework to Ensure and Assess Trustworthiness in Sensor systems (FEATS) to identify attacks on sensor system integrity and inform the operator of sensor data trustworthiness. We have developed and validated unsupervised anomaly detection algorithms for sensor data captured from an experimental acoustic sensor platform under a number of attack scenarios. The platform, which contains four audio microphones, was exposed to two physical attacks (audio filtering and audio playback) as well as a live replay attack (replaying live audio data that is captured at a remote location), which is analogous to a wormhole attack in the routing layer. With our unsupervised learning algorithms, we were able to successfully identify the presence of various attacks.

  4. Smart Grid Integrity Attacks: Characterizations and Countermeasures

    SciTech Connect

    Annarita Giani; Eilyan Bitar; Miles McQueen; Pramod Khargonekar; Kameshwar Poolla

    2011-10-01

    Real power injections at loads and generators, and real power flows on selected lines in a transmission network are monitored, transmitted over a SCADA network to the system operator, and used in state estimation algorithms to make dispatch, re-balance and other energy management system [EMS] decisions. Coordinated cyber attacks of power meter readings can be arranged to be undetectable by any bad data detection algorithm. These unobservable attacks present a serious threat to grid operations. Of particular interest are sparse attacks that involve the compromise of a modest number of meter readings. An efficient algorithm to find all unobservable attacks [under standard DC load flow approximations] involving the compromise of exactly two power injection meters and an arbitrary number of power meters on lines is presented. This requires O(n2m) flops for a power system with n buses and m line meters. If all lines are metered, there exist canonical forms that characterize all 3, 4, and 5-sparse unobservable attacks. These can be quickly detected in power systems using standard graph algorithms. Known secure phase measurement units [PMUs] can be used as countermeasures against an arbitrary collection of cyber attacks. Finding the minimum number of necessary PMUs is NP-hard. It is shown that p + 1 PMUs at carefully chosen buses are sufficient to neutralize a collection of p cyber attacks.

  5. Adaptive cyber-attack modeling system

    NASA Astrophysics Data System (ADS)

    Gonsalves, Paul G.; Dougherty, Edward T.

    2006-05-01

    The pervasiveness of software and networked information systems is evident across a broad spectrum of business and government sectors. Such reliance provides an ample opportunity not only for the nefarious exploits of lone wolf computer hackers, but for more systematic software attacks from organized entities. Much effort and focus has been placed on preventing and ameliorating network and OS attacks, a concomitant emphasis is required to address protection of mission critical software. Typical software protection technique and methodology evaluation and verification and validation (V&V) involves the use of a team of subject matter experts (SMEs) to mimic potential attackers or hackers. This manpower intensive, time-consuming, and potentially cost-prohibitive approach is not amenable to performing the necessary multiple non-subjective analyses required to support quantifying software protection levels. To facilitate the evaluation and V&V of software protection solutions, we have designed and developed a prototype adaptive cyber attack modeling system. Our approach integrates an off-line mechanism for rapid construction of Bayesian belief network (BN) attack models with an on-line model instantiation, adaptation and knowledge acquisition scheme. Off-line model construction is supported via a knowledge elicitation approach for identifying key domain requirements and a process for translating these requirements into a library of BN-based cyber-attack models. On-line attack modeling and knowledge acquisition is supported via BN evidence propagation and model parameter learning.

  6. Situational awareness of a coordinated cyber attack

    NASA Astrophysics Data System (ADS)

    Sudit, Moises; Stotz, Adam; Holender, Michael

    2005-03-01

    As technology continues to advance, services and capabilities become computerized, and an ever increasing amount of business is conducted electronically the threat of cyber attacks gets compounded by the complexity of such attacks and the criticality of the information which must be secured. A new age of virtual warfare has dawned in which seconds can differentiate between the protection of vital information and/or services and a malicious attacker attaining their goal. In this paper we present a novel approach in the real-time detection of multistage coordinated cyber attacks and the promising initial testing results we have obtained. We introduce INFERD (INformation Fusion Engine for Real-time Decision-making), an adaptable information fusion engine which performs fusion at levels zero, one, and two to provide real-time situational assessment and its application to the cyber domain in the ECCARS (Event Correlation for Cyber Attack Recognition System) system. The advantages to our approach are fourfold: (1) The complexity of the attacks which we consider, (2) the level of abstraction in which the analyst interacts with the attack scenarios, (3) the speed at which the information fusion is presented and performed, and (4) our disregard for ad-hoc rules or a priori parameters.

  7. Protecting complex infrastructures against multiple strategic attackers

    NASA Astrophysics Data System (ADS)

    Hausken, Kjell

    2011-01-01

    Infrastructures are analysed subject to defence by a strategic defender and attack by multiple strategic attackers. A framework is developed where each agent determines how much to invest in defending versus attacking each of multiple targets. A target can have economic, human and symbolic values, which generally vary across agents. Investment expenditure functions for each agent can be linear in the investment effort, concave, convex, logistic, can increase incrementally, or can be subject to budget constraints. Contest success functions (e.g., ratio and difference forms) determine the probability of a successful attack on each target, dependent on the relative investments of the defender and attackers on each target, and on characteristics of the contest. Targets can be in parallel, in series, interlinked, interdependent or independent. The defender minimises the expected damage plus the defence expenditures. Each attacker maximises the expected damage minus the attack expenditures. The number of free choice variables equals the number of agents times the number of targets, or lower if there are budget constraints. Each agent is interested in how his investments vary across the targets, and the impact on his utilities. Alternative optimisation programmes are discussed, together with repeated games, dynamic games and incomplete information. An example is provided for illustration.

  8. Use of forensic analysis to better understand shark attack behaviour.

    PubMed

    Ritter, E; Levine, M

    2004-12-01

    Shark attacks have primarily been analyzed from wound patterns, with little knowledge of a shark's approach, behaviour and intention leading to such wounds. For the first time, during a shark-human interaction project in South Africa, a white shark, Carcharodon carcharias, was filmed biting a vertically positioned person at the water surface, and exhibiting distinct approach patterns leading to the bite. This bite was compared to ten white shark attacks that occurred (i) in the same geographical area of South Africa, and (ii) where the same body parts were bitten. Close similarity of some of these wound patterns to the bite imprint of the videotaped case indicate that the observed behaviour of the white shark may represent a common pattern of approaching and biting humans. PMID:16223019

  9. Use of forensic analysis to better understand shark attack behaviour.

    PubMed

    Ritter, E; Levine, M

    2004-12-01

    Shark attacks have primarily been analyzed from wound patterns, with little knowledge of a shark's approach, behaviour and intention leading to such wounds. For the first time, during a shark-human interaction project in South Africa, a white shark, Carcharodon carcharias, was filmed biting a vertically positioned person at the water surface, and exhibiting distinct approach patterns leading to the bite. This bite was compared to ten white shark attacks that occurred (i) in the same geographical area of South Africa, and (ii) where the same body parts were bitten. Close similarity of some of these wound patterns to the bite imprint of the videotaped case indicate that the observed behaviour of the white shark may represent a common pattern of approaching and biting humans.

  10. Dead or Alive? Factors Affecting the Survival of Victims during Attacks by Saltwater Crocodiles (Crocodylus porosus) in Australia.

    PubMed

    Fukuda, Yusuke; Manolis, Charlie; Saalfeld, Keith; Zuur, Alain

    2015-01-01

    Conflicts between humans and crocodilians are a widespread conservation challenge and the number of crocodile attacks is increasing worldwide. We identified the factors that most effectively decide whether a victim is injured or killed in a crocodile attack by fitting generalized linear models to a 42-year dataset of 87 attacks (27 fatal and 60 non-fatal) by saltwater crocodiles (Crocodylus porosus) in Australia. The models showed that the most influential factors were the difference in body mass between crocodile and victim, and the position of victim in relation to the water at the time of an attack. In-water position (for diving, swimming, and wading) had a higher risk than on-water (boating) or on-land (fishing, and hunting near the water's edge) positions. In the in-water position a 75 kg person would have a relatively high probability of survival (0.81) if attacked by a 300 cm crocodile, but the probability becomes much lower (0.17) with a 400 cm crocodile. If attacked by a crocodile larger than 450 cm, the survival probability would be extremely low (<0.05) regardless of the victim's size. These results indicate that the main cause of death during a crocodile attack is drowning and larger crocodiles can drag a victim more easily into deeper water. A higher risk associated with a larger crocodile in relation to victim's size is highlighted by children's vulnerability to fatal attacks. Since the first recently recorded fatal attack involving a child in 2006, six out of nine fatal attacks (66.7%) involved children, and the average body size of crocodiles responsible for these fatal attacks was considerably smaller (384 cm, 223 kg) than that of crocodiles that killed adults (450 cm, 324 kg) during the same period (2006-2014). These results suggest that culling programs targeting larger crocodiles may not be an effective management option to improve safety for children.

  11. Dead or Alive? Factors Affecting the Survival of Victims during Attacks by Saltwater Crocodiles (Crocodylus porosus) in Australia

    PubMed Central

    Fukuda, Yusuke

    2015-01-01

    Conflicts between humans and crocodilians are a widespread conservation challenge and the number of crocodile attacks is increasing worldwide. We identified the factors that most effectively decide whether a victim is injured or killed in a crocodile attack by fitting generalized linear models to a 42-year dataset of 87 attacks (27 fatal and 60 non-fatal) by saltwater crocodiles (Crocodylus porosus) in Australia. The models showed that the most influential factors were the difference in body mass between crocodile and victim, and the position of victim in relation to the water at the time of an attack. In-water position (for diving, swimming, and wading) had a higher risk than on-water (boating) or on-land (fishing, and hunting near the water's edge) positions. In the in-water position a 75 kg person would have a relatively high probability of survival (0.81) if attacked by a 300 cm crocodile, but the probability becomes much lower (0.17) with a 400 cm crocodile. If attacked by a crocodile larger than 450 cm, the survival probability would be extremely low (<0.05) regardless of the victim’s size. These results indicate that the main cause of death during a crocodile attack is drowning and larger crocodiles can drag a victim more easily into deeper water. A higher risk associated with a larger crocodile in relation to victim’s size is highlighted by children’s vulnerability to fatal attacks. Since the first recently recorded fatal attack involving a child in 2006, six out of nine fatal attacks (66.7%) involved children, and the average body size of crocodiles responsible for these fatal attacks was considerably smaller (384 cm, 223 kg) than that of crocodiles that killed adults (450 cm, 324 kg) during the same period (2006–2014). These results suggest that culling programs targeting larger crocodiles may not be an effective management option to improve safety for children. PMID:25961294

  12. Dead or Alive? Factors Affecting the Survival of Victims during Attacks by Saltwater Crocodiles (Crocodylus porosus) in Australia.

    PubMed

    Fukuda, Yusuke; Manolis, Charlie; Saalfeld, Keith; Zuur, Alain

    2015-01-01

    Conflicts between humans and crocodilians are a widespread conservation challenge and the number of crocodile attacks is increasing worldwide. We identified the factors that most effectively decide whether a victim is injured or killed in a crocodile attack by fitting generalized linear models to a 42-year dataset of 87 attacks (27 fatal and 60 non-fatal) by saltwater crocodiles (Crocodylus porosus) in Australia. The models showed that the most influential factors were the difference in body mass between crocodile and victim, and the position of victim in relation to the water at the time of an attack. In-water position (for diving, swimming, and wading) had a higher risk than on-water (boating) or on-land (fishing, and hunting near the water's edge) positions. In the in-water position a 75 kg person would have a relatively high probability of survival (0.81) if attacked by a 300 cm crocodile, but the probability becomes much lower (0.17) with a 400 cm crocodile. If attacked by a crocodile larger than 450 cm, the survival probability would be extremely low (<0.05) regardless of the victim's size. These results indicate that the main cause of death during a crocodile attack is drowning and larger crocodiles can drag a victim more easily into deeper water. A higher risk associated with a larger crocodile in relation to victim's size is highlighted by children's vulnerability to fatal attacks. Since the first recently recorded fatal attack involving a child in 2006, six out of nine fatal attacks (66.7%) involved children, and the average body size of crocodiles responsible for these fatal attacks was considerably smaller (384 cm, 223 kg) than that of crocodiles that killed adults (450 cm, 324 kg) during the same period (2006-2014). These results suggest that culling programs targeting larger crocodiles may not be an effective management option to improve safety for children. PMID:25961294

  13. The association between abdominal obesity and characteristics of migraine attacks in Iranian adults

    PubMed Central

    Sadeghi, Omid; Askari, Gholamreza; Maghsoudi, Zahra; Ghiasvand, Reza; Khorvash, Fariborz

    2016-01-01

    Background: Migraine is a primary headache disorder that affects the neurovascular system. Recent studies have shown that migraine patients with general obesity have higher characteristics of migraine attacks compared with normal weight patients, but data on central obesity are scarce. This study was done to assess the relationship between central obesity and the characteristics of migraine attacks in migraine patients. Materials and Methods: This cross-sectional study was conducted on 129 migraine patients (28 men and 101 women), aged 15–67 years, in Isfahan, Iran. Anthropometric measurements such as waist circumference (WC), hip circumference (HC), waist–hip ratio (WHR) and waist–height ratio (WHtR), as well as characteristics of migraine attacks such as severity, frequency, duration, and headache diary result (HDR) was determined for each participant. Linear regression was used to examine the association between anthropometric measurements and characteristics of migraine attacks. P value less than 0.05 was considered significant. Results: WC, WHR, and WHtR were positively associated with the severity (P-value: WC: 0.002, WHR: 0.002, WHtR: 0.001) and frequency (P-value: WC: 0.006, WHR: 0.01, WHtR: 0.002) of migraine attacks. Moreover, we found a significant association between WC (P = 0.001), WHR (P = 0.004), and WHtR (P < 0.001) with HDR. No significant relationship was observed between central obesity indicators and duration of migraine attacks. Conclusions: Central obesity indicators were positively associated with the severity and frequency of migraine attacks as well as HDR, but not with duration of attacks. Based on our findings, it can be concluded that weight loss may decrease the characteristics of migraine attacks. PMID:27186204

  14. Thatcher condemns attacks on abortion mp.

    PubMed

    1987-12-19

    The Prime Minister, Mrs Margaret Thatcher, has stepped in to condemn a series of violent attacks on Liberal MP David Alton who is trying to reduce the [Illegible word] limit on abortions from 28 to 18 weeks.

  15. Recovery of infrastructure networks after localised attacks

    NASA Astrophysics Data System (ADS)

    Hu, Fuyu; Yeung, Chi Ho; Yang, Saini; Wang, Weiping; Zeng, An

    2016-04-01

    The stability of infrastructure network is always a critical issue studied by researchers in different fields. A lot of works have been devoted to reveal the robustness of the infrastructure networks against random and malicious attacks. However, real attack scenarios such as earthquakes and typhoons are instead localised attacks which are investigated only recently. Unlike previous studies, we examine in this paper the resilience of infrastructure networks by focusing on the recovery process from localised attacks. We introduce various preferential repair strategies and found that they facilitate and improve network recovery compared to that of random repairs, especially when population size is uneven at different locations. Moreover, our strategic repair methods show similar effectiveness as the greedy repair. The validations are conducted on simulated networks, and on real networks with real disasters. Our method is meaningful in practice as it can largely enhance network resilience and contribute to network risk reduction.

  16. Recovery of infrastructure networks after localised attacks.

    PubMed

    Hu, Fuyu; Yeung, Chi Ho; Yang, Saini; Wang, Weiping; Zeng, An

    2016-01-01

    The stability of infrastructure network is always a critical issue studied by researchers in different fields. A lot of works have been devoted to reveal the robustness of the infrastructure networks against random and malicious attacks. However, real attack scenarios such as earthquakes and typhoons are instead localised attacks which are investigated only recently. Unlike previous studies, we examine in this paper the resilience of infrastructure networks by focusing on the recovery process from localised attacks. We introduce various preferential repair strategies and found that they facilitate and improve network recovery compared to that of random repairs, especially when population size is uneven at different locations. Moreover, our strategic repair methods show similar effectiveness as the greedy repair. The validations are conducted on simulated networks, and on real networks with real disasters. Our method is meaningful in practice as it can largely enhance network resilience and contribute to network risk reduction.

  17. Diabetes - preventing heart attack and stroke

    MedlinePlus

    Diabetes complications - heart; Coronary artery disease - diabetes; CAD - diabetes; Cerebrovascular disease - diabetes ... People with diabetes have a higher chance of having heart attacks and strokes. Smoking and having high blood pressure and high ...

  18. Identifying and Analyzing Web Server Attacks

    SciTech Connect

    Seifert, Christian; Endicott-Popovsky, Barbara E.; Frincke, Deborah A.; Komisarczuk, Peter; Muschevici, Radu; Welch, Ian D.

    2008-08-29

    Abstract: Client honeypots can be used to identify malicious web servers that attack web browsers and push malware to client machines. Merely recording network traffic is insufficient to perform comprehensive forensic analyses of such attacks. Custom tools are required to access and analyze network protocol data. Moreover, specialized methods are required to perform a behavioral analysis of an attack, which helps determine exactly what transpired on the attacked system. This paper proposes a record/replay mechanism that enables forensic investigators to extract application data from recorded network streams and allows applications to interact with this data in order to conduct behavioral analyses. Implementations for the HTTP and DNS protocols are presented and their utility in network forensic investigations is demonstrated.

  19. Recovery of infrastructure networks after localised attacks

    PubMed Central

    Hu, Fuyu; Yeung, Chi Ho; Yang, Saini; Wang, Weiping; Zeng, An

    2016-01-01

    The stability of infrastructure network is always a critical issue studied by researchers in different fields. A lot of works have been devoted to reveal the robustness of the infrastructure networks against random and malicious attacks. However, real attack scenarios such as earthquakes and typhoons are instead localised attacks which are investigated only recently. Unlike previous studies, we examine in this paper the resilience of infrastructure networks by focusing on the recovery process from localised attacks. We introduce various preferential repair strategies and found that they facilitate and improve network recovery compared to that of random repairs, especially when population size is uneven at different locations. Moreover, our strategic repair methods show similar effectiveness as the greedy repair. The validations are conducted on simulated networks, and on real networks with real disasters. Our method is meaningful in practice as it can largely enhance network resilience and contribute to network risk reduction. PMID:27075559

  20. On localization attacks against cloud infrastructure

    NASA Astrophysics Data System (ADS)

    Ge, Linqiang; Yu, Wei; Sistani, Mohammad Ali

    2013-05-01

    One of the key characteristics of cloud computing is the device and location independence that enables the user to access systems regardless of their location. Because cloud computing is heavily based on sharing resource, it is vulnerable to cyber attacks. In this paper, we investigate a localization attack that enables the adversary to leverage central processing unit (CPU) resources to localize the physical location of server used by victims. By increasing and reducing CPU usage through the malicious virtual machine (VM), the response time from the victim VM will increase and decrease correspondingly. In this way, by embedding the probing signal into the CPU usage and correlating the same pattern in the response time from the victim VM, the adversary can find the location of victim VM. To determine attack accuracy, we investigate features in both the time and frequency domains. We conduct both theoretical and experimental study to demonstrate the effectiveness of such an attack.

  1. Correlations in complex networks under attack.

    PubMed

    Srivastava, Animesh; Mitra, Bivas; Ganguly, Niloy; Peruani, Fernando

    2012-09-01

    For any initially correlated network after any kind of attack where either nodes or edges are removed, we obtain general expressions for the degree-degree probability matrix and degree distribution. We show that the proposed analytical approach predicts the correct topological changes after the attack by comparing the evolution of the assortativity coefficient for different attack strategies and intensities in theory and simulations. We find that it is possible to turn an initially assortative network into a disassortative one, and vice versa, by fine-tuning removal of either nodes or edges. For an initially uncorrelated network, on the other hand, we discover that only a targeted edge-removal attack can induce such correlations. PMID:23030979

  2. Death by attack from a domestic buffalo.

    PubMed

    Bakkannavar, Shankar M; Monteiro, Francis N P; Bhagavath, Prashantha; Pradeep Kumar, G

    2010-02-01

    Attacks on humans by domestic animals causing fatal injuries are not uncommon in rural areas of India. But injuries due to buffalo gore are rarely observed in villages and are different from other casualties like stab injuries, road fatalities, etc. As the victims of buffalo attack are usually recovered from the fields or forest, the investigating officer could be mislead as to the nature of infliction of fatal injuries to a possible homicide. The injuries caused by the horns of buffaloes are of various shapes, sizes and directions. They are violent and goring in nature. The wound sustained may be contusions, lacerations, criss-cross wounds, penetration of body cavities, and sometimes fractures. In the absence of any eye witness, it becomes very difficult to believe the unsuspecting domestic water buffalo as attacker. This case is reported for its rarity, for the awareness of the possible injuries in such unnatural deaths, and factors predisposing to a buffalo attack.

  3. Recovery of infrastructure networks after localised attacks.

    PubMed

    Hu, Fuyu; Yeung, Chi Ho; Yang, Saini; Wang, Weiping; Zeng, An

    2016-01-01

    The stability of infrastructure network is always a critical issue studied by researchers in different fields. A lot of works have been devoted to reveal the robustness of the infrastructure networks against random and malicious attacks. However, real attack scenarios such as earthquakes and typhoons are instead localised attacks which are investigated only recently. Unlike previous studies, we examine in this paper the resilience of infrastructure networks by focusing on the recovery process from localised attacks. We introduce various preferential repair strategies and found that they facilitate and improve network recovery compared to that of random repairs, especially when population size is uneven at different locations. Moreover, our strategic repair methods show similar effectiveness as the greedy repair. The validations are conducted on simulated networks, and on real networks with real disasters. Our method is meaningful in practice as it can largely enhance network resilience and contribute to network risk reduction. PMID:27075559

  4. Cyber Security Audit and Attack Detection Toolkit

    SciTech Connect

    Peterson, Dale

    2012-05-31

    This goal of this project was to develop cyber security audit and attack detection tools for industrial control systems (ICS). Digital Bond developed and released a tool named Bandolier that audits ICS components commonly used in the energy sector against an optimal security configuration. The Portaledge Project developed a capability for the PI Historian, the most widely used Historian in the energy sector, to aggregate security events and detect cyber attacks.

  5. Heart Attack - Multiple Languages: MedlinePlus

    MedlinePlus

    ... Arabic) النوبة القلبية - العربية Bilingual PDF Health Information Translations Bosnian (Bosanski) Heart Attack Srčani udar - Bosanski (Bosnian) Bilingual PDF Health Information Translations Chinese - Simplified (简体中文) Heart Attack 心脏病发作 - 简体中文 (Chinese - ...

  6. Distinguishing attack and second-preimage attack on encrypted message authentication codes (EMAC)

    NASA Astrophysics Data System (ADS)

    Ariwibowo, Sigit; Windarta, Susila

    2016-02-01

    In this paper we show that distinguisher on CBC-MAC can be applied to Encrypted Message Authentication Code (EMAC) scheme. EMAC scheme in general is vulnerable to distinguishing attack and second preimage attack. Distinguishing attack simulation on AES-EMAC using 225 message modifications, no collision have been found. According to second preimage attack simulation on AES-EMAC no collision found between EMAC value of S1 and S2, i.e. no second preimage found for messages that have been tested. Based on distinguishing attack simulation on truncated AES-EMAC we found collision in every message therefore we cannot distinguish truncated AES-EMAC with random function. Second-preimage attack is successfully performed on truncated AES-EMAC.

  7. Diffusion Weighted Imaging in Acute Attacks of Multiple Sclerosis

    PubMed Central

    Davoudi, Yasmin; Foroughipour, Mohsen; Torabi, Reza; Layegh, Parvaneh; Matin, Nassim; Shoeibi, Ali

    2016-01-01

    Background Multiple sclerosis (MS) is one of the most common autoimmune disorders of the central nervous system. In spite of various imaging modalities, the definitive diagnosis of MS remains challenging. Objectives This study was designed to evaluate the usefulness of diffusion weighted imaging (DWI) in the diagnosis of acute MS attack and to compare its results with contrast enhanced MRI (CE-MRI). Patients and Methods In this cross sectional study, seventy patients with definite diagnosis of relapsing-remitting MS were included. CE-MRI using 0.1 mmol/kg gadolinium as well as DWI sequences were performed for all patients. The percentage of patients with positive DWI was compared with the results of CE-MRI and the consistency between the two imaging modalities was evaluated. Moreover, the relationship between the time of onset of patient’s symptoms and test results for both methods were investigated. Results CE-MRI yielded positive results for 61 (87%) patients and DWI yielded positive for 53 (76%) patients. In fifty patients (71.42%), both tests were positive and in six cases (8.57%), both were negative. The test results of three patients turned out to be positive in DWI, while they tested negative in CE-MRI. There was no significant relationship between the results of CE-MRI as well as DWI and the time of imaging from the onset of symptoms. Conclusion These data indicate that while CE-MRI will depict more positive results, there are cases in which DWI will show a positive result while CE-MRI is negative. We suggest that the combination of these two imaging modalities might yield more positive results in diagnosing acute MS attack giving rise to a more accurate diagnosis.

  8. Generation of plasmin during acute attacks of hereditary angioedema.

    PubMed

    Cugno, M; Hack, C E; de Boer, J P; Eerenberg, A J; Agostoni, A; Cicardi, M

    1993-01-01

    Hereditary angioedema is caused by a genetic deficiency of C1-inhibitor, a serine protease inhibitor that regulates activation of complement, contact, and fibrinolytic systems. Symptoms (bouts of subcutaneous and mucous swelling) depend on the release of a vasoactive mediator, probably through activation of these three systems. We studied the interrelationship among complement, contact, and fibrinolytic activation in 23 patients with hereditary angiodema, 18 during remission and five during an attack, by measuring plasma levels of C1-C1 inhibitor, factor XIIa-C1 inhibitor, kallikrein-C1 inhibitor, and plasmin-alpha 2-antiplasmin complexes, tissue plasminogen activator, and urokinase plasminogen activator. In addition, cleavage of high-molecular weight kininogen was detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis and quantified by densitometry. During remission, plasma levels of C1-C1 inhibitor complexes were elevated (p = 0.0002), whereas the other parameters were within the normal range. During acute attacks, not only plasma levels of C1-C1 inhibitor complexes but also those of plasmin-alpha 2-antiplasmin complexes (P = 0.0009) and cleaved high-molecular weight kininogen were elevated. A positive correlation between plasmin-alpha 2-antiplasmin complexes and cleaved high-molecular weight kininogen was observed (r = 0.75, p < 0.001). This article presents the first in vivo evidence that supports the concept that release of vasoactive mediators in hereditary angiodema attacks is associated with the activation of the fibrinolytic system.

  9. Pathologic features of fatal shark attacks.

    PubMed

    Byard, R W; Gilbert, J D; Brown, K

    2000-09-01

    To examine the pattern of injuries in cases of fatal shark attack in South Australian waters, the authors examined the files of their institution for all cases of shark attack in which full autopsies had been performed over the past 25 years, from 1974 to 1998. Of the seven deaths attributed to shark attack during this period, full autopsies were performed in only two cases. In the remaining five cases, bodies either had not been found or were incomplete. Case 1 was a 27-year-old male surfer who had been attacked by a shark. At autopsy, the main areas of injury involved the right thigh, which displayed characteristic teeth marks, extensive soft tissue damage, and incision of the femoral artery. There were also incised wounds of the right wrist. Bony injury was minimal, and no shark teeth were recovered. Case 2 was a 26-year-old male diver who had been attacked by a shark. At autopsy, the main areas of injury involved the left thigh and lower leg, which displayed characteristic teeth marks, extensive soft tissue damage, and incised wounds of the femoral artery and vein. There was also soft tissue trauma to the left wrist, with transection of the radial artery and vein. Bony injury was minimal, and no shark teeth were recovered. In both cases, death resulted from exsanguination following a similar pattern of soft tissue and vascular damage to a leg and arm. This type of injury is in keeping with predator attack from underneath or behind, with the most severe injuries involving one leg. Less severe injuries to the arms may have occurred during the ensuing struggle. Reconstruction of the damaged limb in case 2 by sewing together skin, soft tissue, and muscle bundles not only revealed that no soft tissue was missing but also gave a clearer picture of the pattern of teeth marks, direction of the attack, and species of predator.

  10. Coronary Artery Dissection: Not Just a Heart Attack

    MedlinePlus

    ... Stroke More Coronary Artery Dissection: Not Just a Heart Attack Updated:May 24,2016 Sometimes a heart attack ... Disease Go Red For Women Types of aneurysms Heart Attack • Home • About Heart Attacks Acute Coronary Syndrome (ACS) • ...

  11. A Game Theoretic Approach to Cyber Attack Prediction

    SciTech Connect

    Peng Liu

    2005-11-28

    The area investigated by this project is cyber attack prediction. With a focus on correlation-based prediction, current attack prediction methodologies overlook the strategic nature of cyber attack-defense scenarios. As a result, current cyber attack prediction methodologies are very limited in predicting strategic behaviors of attackers in enforcing nontrivial cyber attacks such as DDoS attacks, and may result in low accuracy in correlation-based predictions. This project develops a game theoretic framework for cyber attack prediction, where an automatic game-theory-based attack prediction method is proposed. Being able to quantitatively predict the likelihood of (sequences of) attack actions, our attack prediction methodology can predict fine-grained strategic behaviors of attackers and may greatly improve the accuracy of correlation-based prediction. To our best knowledge, this project develops the first comprehensive framework for incentive-based modeling and inference of attack intent, objectives, and strategies; and this project develops the first method that can predict fine-grained strategic behaviors of attackers. The significance of this research and the benefit to the public can be demonstrated to certain extent by (a) the severe threat of cyber attacks to the critical infrastructures of the nation, including many infrastructures overseen by the Department of Energy, (b) the importance of cyber security to critical infrastructure protection, and (c) the importance of cyber attack prediction to achieving cyber security.

  12. Performance Evaluation of AODV with Blackhole Attack

    NASA Astrophysics Data System (ADS)

    Dara, Karuna

    2010-11-01

    A Mobile Ad Hoc Network (MANET) is a temporary network set up by a wireless mobile computers moving arbitrary in the places that have no network infrastructure. These nodes maintain connectivity in a decentralized manner. Since the nodes communicate with each other, they cooperate by forwarding data packets to other nodes in the network. Thus the nodes find a path to the destination node using routing protocols. However, due to security vulnerabilities of the routing protocols, mobile ad-hoc networks are unprotected to attacks of the malicious nodes. One of these attacks is the Black Hole Attack against network integrity absorbing all data packets in the network. Since the data packets do not reach the destination node on account of this attack, data loss will occur. In this paper, we simulated the black hole attack in various mobile ad-hoc network scenarios using AODV routing protocol of MANET and have tried to find a effect if number of nodes are increased with increase in malicious nodes.

  13. Characterization of attacks on public telephone networks

    NASA Astrophysics Data System (ADS)

    Lorenz, Gary V.; Manes, Gavin W.; Hale, John C.; Marks, Donald; Davis, Kenneth; Shenoi, Sujeet

    2001-02-01

    The U.S. Public Telephone Network (PTN) is a massively connected distributed information systems, much like the Internet. PTN signaling, transmission and operations functions must be protected from physical and cyber attacks to ensure the reliable delivery of telecommunications services. The increasing convergence of PTNs with wireless communications systems, computer networks and the Internet itself poses serious threats to our nation's telecommunications infrastructure. Legacy technologies and advanced services encumber well-known and as of yet undiscovered vulnerabilities that render them susceptible to cyber attacks. This paper presents a taxonomy of cyber attacks on PTNs in converged environments that synthesizes exploits in computer and communications network domains. The taxonomy provides an opportunity for the systematic exploration of mitigative and preventive strategies, as well as for the identification and classification of emerging threats.

  14. Quantifying Mixed Uncertainties in Cyber Attacker Payoffs

    SciTech Connect

    Chatterjee, Samrat; Halappanavar, Mahantesh; Tipireddy, Ramakrishna; Oster, Matthew R.; Saha, Sudip

    2015-04-15

    Representation and propagation of uncertainty in cyber attacker payoffs is a key aspect of security games. Past research has primarily focused on representing the defender’s beliefs about attacker payoffs as point utility estimates. More recently, within the physical security domain, attacker payoff uncertainties have been represented as Uniform and Gaussian probability distributions, and intervals. Within cyber-settings, continuous probability distributions may still be appropriate for addressing statistical (aleatory) uncertainties where the defender may assume that the attacker’s payoffs differ over time. However, systematic (epistemic) uncertainties may exist, where the defender may not have sufficient knowledge or there is insufficient information about the attacker’s payoff generation mechanism. Such epistemic uncertainties are more suitably represented as probability boxes with intervals. In this study, we explore the mathematical treatment of such mixed payoff uncertainties.

  15. A Traceability Attack against e-Passports

    NASA Astrophysics Data System (ADS)

    Chothia, Tom; Smirnov, Vitaliy

    Since 2004, many nations have started issuing "e-passports" containing an RFID tag that, when powered, broadcasts information. It is claimed that these passports are more secure and that our data will be protected from any possible unauthorised attempts to read it. In this paper we show that there is a flaw in one of the passport's protocols that makes it possible to trace the movements of a particular passport, without having to break the passport's cryptographic key. All an attacker has to do is to record one session between the passport and a legitimate reader, then by replaying a particular message, the attacker can distinguish that passport from any other. We have implemented our attack and tested it successfully against passports issued by a range of nations.

  16. Resistance of the double random phase encryption against various attacks.

    PubMed

    Frauel, Yann; Castro, Albertina; Naughton, Thomas J; Javidi, Bahram

    2007-08-01

    Several attacks are proposed against the double random phase encryption scheme. These attacks are demonstrated on computer-generated ciphered images. The scheme is shown to be resistant against brute force attacks but susceptible to chosen and known plaintext attacks. In particular, we describe a technique to recover the exact keys with only two known plain images. We compare this technique to other attacks proposed in the literature.

  17. Discovering Collaborative Cyber Attack Patterns Using Social Network Analysis

    NASA Astrophysics Data System (ADS)

    Du, Haitao; Yang, Shanchieh Jay

    This paper investigates collaborative cyber attacks based on social network analysis. An Attack Social Graph (ASG) is defined to represent cyber attacks on the Internet. Features are extracted from ASGs to analyze collaborative patterns. We use principle component analysis to reduce the feature space, and hierarchical clustering to group attack sources that exhibit similar behavior. Experiments with real world data illustrate that our framework can effectively reduce from large dataset to clusters of attack sources exhibiting critical collaborative patterns.

  18. Counterfactual attack on counterfactual quantum key distribution

    NASA Astrophysics Data System (ADS)

    Zhang, Sheng; Wnang, Jian; Tang, Chao Jing

    2012-05-01

    It is interesting that counterfactual quantum cryptography protocols allow two remotely separated parties to share a secret key without transmitting any signal particles. Generally, these protocols, expected to provide security advantages, base their security on a translated no-cloning theorem. Therefore, they potentially exhibit unconditional security in theory. In this letter, we propose a new Trojan horse attack, by which an eavesdropper Eve can gain full information about the key without being noticed, to real implementations of a counterfactual quantum cryptography system. Most importantly, the presented attack is available even if the system has negligible imperfections. Therefore, it shows that the present realization of counterfactual quantum key distribution is vulnerable.

  19. Identifying inference attacks against healthcare data repositories

    PubMed Central

    Vaidya, Jaideep; Shafiq, Basit; Jiang, Xiaoqian; Ohno-Machado, Lucila

    Health care data repositories play an important role in driving progress in medical research. Finding new pathways to discovery requires having adequate data and relevant analysis. However, it is critical to ensure the privacy and security of the stored data. In this paper, we identify a dangerous inference attack against naive suppression based approaches that are used to protect sensitive information. We base our attack on the querying system provided by the Healthcare Cost and Utilization Project, though it applies in general to any medical database providing a query capability. We also discuss potential solutions to this problem. PMID:24303279

  20. Differential attack on mini-AES

    NASA Astrophysics Data System (ADS)

    Ajeng Gemellia, Asadini Dwi; Indarjani, Santi

    2012-05-01

    This paper presents the results of differential attack on Mini-AES algorithm. The differential trails are constructed using all combinations of propagation ratio without repetition. To give practical results, we implement the key extraction for differential characteristics which have the highest and lowest probability as a comparison. Based on total propagation ratio and complexity resulted, Mini-AES algorithms are vulnerable to differential attack. The best differential characteristic is the differential characteristic using a single active s-box with the propagation ratio of 8 / 16.

  1. High-angle-of-attack yawing moment asymmetry of the X-31 aircraft from flight test

    NASA Technical Reports Server (NTRS)

    Cobleigh, Brent R.

    1994-01-01

    Significant yawing moment asymmetries were encountered during the high-angle-of-attack envelope expansion of the two X-31 aircraft. These asymmetries led to position saturations of the thrust vector vanes and trailing-edge flaps during some of the dynamic stability axis rolling maneuvers at high angles of attack. This slowed the high-angle-of-attack envelope expansion and resulted in maneuver restrictions. Several aerodynamic modifications were made to the X-31 forebody with the goal of minimizing the asymmetry. A method for determining the yawing moment asymmetry from flight data was developed and an analysis of the various configuration changes completed. The baseline aircraft were found to have significant asymmetries above 45 deg angle of attack with the largest asymmetry typically occurring around 60 deg angle of attack. Applying symmetrical boundary layer transition strips along the forebody sides increased the magnitude of the asymmetry and widened the angle-of-attack range over which the largest asymmetry acted. Installing longitudinal forebody strakes and rounding the sharp nose of the aircraft caused the yawing moment asymmetry magnitude to be reduced. The transition strips and strakes made the asymmetry characteristic of the aircraft more repeatable than the clean forebody configuration. Although no geometric differences between the aircraft were known, ship 2 consistently had larger yawing moment asymmetries than ship 1.

  2. Characteristics of individuals meeting criteria for new onset panic attacks following exposure to a typhoon.

    PubMed

    Roberson-Nay, Roxann; Berenz, Erin C; Acierno, Ron; Tran, Trinh Luong; Trung, Lam Tu; Tam, Nguyen Thanh; Tuan, Tran; Buoi, La Thi; Ha, Tran Thu; Thach, Tran Duc; Amstadter, Ananda B

    2013-10-30

    The association between trauma exposure and panic attacks has received increased attention over the past decade, with mounting evidence suggesting an overlapping etiologic pathway. This study examined the incidence of new onset panic attacks in 775 Vietnamese individuals in the 2-3 months following Typhoon Xangsane. Pre-typhoon (Wave 1) and post-typhoon (Wave 2) assessments were conducted, allowing for consideration of factors occurring prior to the typhoon in addition to typhoon-relevant responding. Of the 775 participants, 11.6% (n=90) met criteria for lifetime panic attack pre-typhoon and 2.8% (n=22) met post-typhoon panic attack criteria. Individuals with pre-typhoon panic were significantly older and reported less education compared to the no-panic group. Individuals in both panic groups were more likely to screen positive on a Wave1 psychiatric screening measure, endorse greater typhoon exposure and prior traumatic event exposure and were significantly more likely to meet DSM-IV criteria for posttraumatic stress disorder (PTSD) and major depression (MDD) post-typhoon compared with persons reporting no history of panic attacks. Pre and post-typhoon panic exhibited similar patterns across variables and both panic conditions were associated with the development of PTSD and MDD, suggesting that persons experiencing panic attacks may represent a vulnerable population in need of early intervention services. PMID:23778303

  3. Characteristics of individuals meeting criteria for new onset panic attacks following exposure to a typhoon.

    PubMed

    Roberson-Nay, Roxann; Berenz, Erin C; Acierno, Ron; Tran, Trinh Luong; Trung, Lam Tu; Tam, Nguyen Thanh; Tuan, Tran; Buoi, La Thi; Ha, Tran Thu; Thach, Tran Duc; Amstadter, Ananda B

    2013-10-30

    The association between trauma exposure and panic attacks has received increased attention over the past decade, with mounting evidence suggesting an overlapping etiologic pathway. This study examined the incidence of new onset panic attacks in 775 Vietnamese individuals in the 2-3 months following Typhoon Xangsane. Pre-typhoon (Wave 1) and post-typhoon (Wave 2) assessments were conducted, allowing for consideration of factors occurring prior to the typhoon in addition to typhoon-relevant responding. Of the 775 participants, 11.6% (n=90) met criteria for lifetime panic attack pre-typhoon and 2.8% (n=22) met post-typhoon panic attack criteria. Individuals with pre-typhoon panic were significantly older and reported less education compared to the no-panic group. Individuals in both panic groups were more likely to screen positive on a Wave1 psychiatric screening measure, endorse greater typhoon exposure and prior traumatic event exposure and were significantly more likely to meet DSM-IV criteria for posttraumatic stress disorder (PTSD) and major depression (MDD) post-typhoon compared with persons reporting no history of panic attacks. Pre and post-typhoon panic exhibited similar patterns across variables and both panic conditions were associated with the development of PTSD and MDD, suggesting that persons experiencing panic attacks may represent a vulnerable population in need of early intervention services.

  4. Angular relationships regulate coordination tendencies of performers in attacker-defender dyads in team sports.

    PubMed

    Esteves, Pedro T; Araújo, Duarte; Vilar, Luís; Travassos, Bruno; Davids, Keith; Esteves, Carlos

    2015-04-01

    This study examined the continuous interpersonal interactions of performers in dyadic systems in team sports, as a function of changing information constraints. As a task vehicle, we investigated how attackers attained success in 1v1 sub-phases of basketball by exploring angular relations with immediate opponents and the basket. We hypothesized that angular relations would convey information for the attackers to dribble past defenders. Four basketball players performed as an attacker and defender in 1v1 sub-phases of basketball, in which the co-positioning and orientation of participants relative to the basket was manipulated. After video recording performance behaviors, we digitized participant movement displacement trajectories and categorized trials as successful or unsuccessful (from the attackers' viewpoint). Results revealed that, to successfully dribble past a defender, attackers tended to explore the left hand side of the space by defenders by increasing their angular velocity and decreasing their angular variability, especially in the center of the court. Interpersonal interactions and goal-achievement in attacker-defender dyads appear to have been constrained by the angular relations sustained between participants relative to the scoring target. Results revealed the functionality of exploratory behaviors of participants attempting re-align spatial relations with an opponent in 1v1 sub-phases of team games. PMID:25625811

  5. Angular relationships regulate coordination tendencies of performers in attacker-defender dyads in team sports.

    PubMed

    Esteves, Pedro T; Araújo, Duarte; Vilar, Luís; Travassos, Bruno; Davids, Keith; Esteves, Carlos

    2015-04-01

    This study examined the continuous interpersonal interactions of performers in dyadic systems in team sports, as a function of changing information constraints. As a task vehicle, we investigated how attackers attained success in 1v1 sub-phases of basketball by exploring angular relations with immediate opponents and the basket. We hypothesized that angular relations would convey information for the attackers to dribble past defenders. Four basketball players performed as an attacker and defender in 1v1 sub-phases of basketball, in which the co-positioning and orientation of participants relative to the basket was manipulated. After video recording performance behaviors, we digitized participant movement displacement trajectories and categorized trials as successful or unsuccessful (from the attackers' viewpoint). Results revealed that, to successfully dribble past a defender, attackers tended to explore the left hand side of the space by defenders by increasing their angular velocity and decreasing their angular variability, especially in the center of the court. Interpersonal interactions and goal-achievement in attacker-defender dyads appear to have been constrained by the angular relations sustained between participants relative to the scoring target. Results revealed the functionality of exploratory behaviors of participants attempting re-align spatial relations with an opponent in 1v1 sub-phases of team games.

  6. Panic attacks 10 years after heart transplantation successfully treated with low-dose citalopram: a case report.

    PubMed

    Ye, Chenyu; Zhuang, Yamin; Ji, Jianlin; Chen, Hao

    2015-12-25

    Panic attacks are common among patients who have undergone heart transplantation, but there are no clinical guidelines for the treatment of panic attacks in this group of patients. This report describes a 22-year-old woman who experienced panic attacks 10 years after heart transplant surgery. The attacks started after she discovered that the average post-transplantation survival is 10 years. Treated with citalopram 10 mg/d, her symptoms improved significantly after 2 weeks and had completely resolved after 8 weeks. A positive physician-patient relationship with the doctors who regularly followed her medical condition was crucial to encouraging her to adhere to the treatment with citalopram. She continued taking the citalopram for 7 months without any adverse effects. When followed up 3 months after stopping the citalopram, she had had no recurrence of the panic attacks. PMID:27199531

  7. Media participation and mental health in terrorist attack survivors.

    PubMed

    Thoresen, Siri; Jensen, Tine K; Dyb, Grete

    2014-12-01

    Terrorism and disasters receive massive media attention, and victims are often approached by reporters. Not much is known about how terror and disaster victims perceive the contact with media and whether such experiences influence mental health. In this study, we describe how positive and negative experiences with media relate to posttraumatic stress (PTS) reactions among survivors of the 2011 Utøya Island terrorist attack in Norway. Face-to-face interviews were conducted with 285 survivors (47.0% female and 53.0% male) 14-15 months after the terrorist attack. Most survivors were approached by reporters (94%), and participated in media interviews (88%). The majority of survivors evaluated their media contact and participation as positive, and media participation was unrelated to PTS reactions. Survivors who found media participation distressing had more PTS reactions (quite distressing: B = 0.440, extremely distressing: B = 0.611, p = .004 in adjusted model). Perceiving media participation as distressing was slightly associated with lower levels of social support (r = -.16, p = .013), and regretting media participation was slightly associated with feeling let down (r = .18, p = .004). Reporters should take care when interviewing victims, and clinicians should be aware of media exposure as a potential additional strain on victims.

  8. Correlation of forebody pressures and aircraft yawing moments on the X-29A aircraft at high angles of attack

    NASA Technical Reports Server (NTRS)

    Fisher, David F.; Richwine, David M.; Landers, Stephen

    1992-01-01

    In-flight pressure distributions at four fuselage stations on the forebody of the X-29A aircraft have been reported at angles of attack from 15 to 66 deg and at Mach numbers from 0.22 to 0.60. At angles of attack of 20 deg and higher, vortices shed from the nose strake caused suction peaks in the pressure distributions that generally increased in magnitude with angle of attack. Above 30 deg-angle of attack, the forebody pressure distributions became asymmetrical at the most forward station, while they remained nearly symmetrical until 50 to 55 deg-angle of attack for the aft stations. Between 59 to 66 deg-angle of attack, the asymmetry of the pressure distributions changed direction. Yawing moments for the forebody alone were obtained by integrating the forebody pressure distributions. At 45 deg-angle of attack, the aircraft yaws to the right and at 50 deg and higher, the aircraft yaws to the left. The forebody yawing moments correlated well with the aircraft left yawing moment at an angle of attack of 50 deg or higher. At a 45 deg-angle of attack, the forebody yawing moments did not correlate well with the aircraft yawing moment, but it is suggested that this was due to asymmetric pressures on the cockpit region of the fuselage which was not instrumented. The forebody was also shown to provide a positive component of directional stability of the aircraft at angles of attack of 25 deg or higher. A Mach number effect was noted at angles of attack of 30 deg or higher at the station where the nose strake was present. At this station, the suction peaks in the pressure distributions at the highest Mach number were reduced and much more symmetrical as compared to the lower Mach number pressure distributions.

  9. Adversarial Feature Selection Against Evasion Attacks.

    PubMed

    Zhang, Fei; Chan, Patrick P K; Biggio, Battista; Yeung, Daniel S; Roli, Fabio

    2016-03-01

    Pattern recognition and machine learning techniques have been increasingly adopted in adversarial settings such as spam, intrusion, and malware detection, although their security against well-crafted attacks that aim to evade detection by manipulating data at test time has not yet been thoroughly assessed. While previous work has been mainly focused on devising adversary-aware classification algorithms to counter evasion attempts, only few authors have considered the impact of using reduced feature sets on classifier security against the same attacks. An interesting, preliminary result is that classifier security to evasion may be even worsened by the application of feature selection. In this paper, we provide a more detailed investigation of this aspect, shedding some light on the security properties of feature selection against evasion attacks. Inspired by previous work on adversary-aware classifiers, we propose a novel adversary-aware feature selection model that can improve classifier security against evasion attacks, by incorporating specific assumptions on the adversary's data manipulation strategy. We focus on an efficient, wrapper-based implementation of our approach, and experimentally validate its soundness on different application examples, including spam and malware detection. PMID:25910268

  10. Triage of casualties after nuclear attack.

    PubMed

    Pledger, H G

    1986-09-20

    Casualties from a nuclear attack on the United Kingdom would overwhelm the health services, and health workers would be faced with many more people seeking help than could be offered treatment. Discussion is needed to determine which methods of medical and non-medical triage would be acceptable and feasible.

  11. The anthrax attacks 10 years later.

    PubMed

    Bush, Larry M; Perez, Maria T

    2012-01-01

    Ten years ago, just weeks after the September 11 attacks, the United States experienced a deliberate act of bioterrorism. Through use of the postal service, anthrax spores were widely disseminated, including to homes, the Senate, and major newsrooms, resulting in morbidity and mortality and effectively disrupting our way of life and revealing our vulnerability. Even though such attacks had been the subject of much writing and had been planned for, detection of and the appropriate response to an attack with an agent from the so-called "Category 'A' List" had only been considered in theoretical terms. What transpired during the following difficult weeks, including how public health and federal government agencies performed, has been both praised and criticized. An intertwined epidemiologic and criminal investigation of such magnitude was unprecedented in U.S. history. To address the question of whether we as a nation are now better prepared for future threats involving biologic agents, it is important to learn from the lessons of the 2001 anthrax attacks, including the critical role of clinicians in surveillance. As physicians involved in diagnosing anthrax in the index case and alerting authorities, we offer our perspective on these events a decade after their occurrence. PMID:21969275

  12. CASE STUDY: DIELDRIN ATTACK IN DALYAN LAGOON

    EPA Science Inventory

    During the first two weeks of December 2005, NATO sponsored an Advanced Study Institute (ASI) in Istanbul, Turkey. Part of this ASI involved a case study of a terrorist attack, where a chemical was assumed to be dumped into Sulunger Lake in Turkey. This chapter documents the re...

  13. Intrusion-Tolerant Replication under Attack

    ERIC Educational Resources Information Center

    Kirsch, Jonathan

    2010-01-01

    Much of our critical infrastructure is controlled by large software systems whose participants are distributed across the Internet. As our dependence on these critical systems continues to grow, it becomes increasingly important that they meet strict availability and performance requirements, even in the face of malicious attacks, including those…

  14. Rhode Island School Terrorist Attack Preparedness

    ERIC Educational Resources Information Center

    Dube, Michael W. M.

    2012-01-01

    This study examined the state of safety and terrorist attack preparedness in Rhode Island Schools as determined by Rhode Island school leader perceptions. The study is descriptive in nature as it gathers data to describe a particular event or situation. Using a researcher generated survey based on terrorist preparedness guidelines and suggestions…

  15. Shark Attack! Sinking Your Teeth into Anatomy.

    ERIC Educational Resources Information Center

    House, Herbert

    2002-01-01

    Presents a real life shark attack story and studies arm reattachment surgery to teach human anatomy. Discusses how knowledge of anatomy can be put to use in the real world and how the arm functions. Includes teaching notes and suggestions for classroom management. (YDS)

  16. Association between Terror Attacks and Suicide Attempts

    ERIC Educational Resources Information Center

    Weizman, Tal; Yagil, Yaron; Schreiber, Shaul

    2009-01-01

    Based on Durkheim's "Control theory," we explored the association between frequency of terror attacks in Israel and the frequency of suicide attempts admitted to the Emergency Room of a major general hospital in Tel-Aviv (1999-2004). Analysis of the six-year study period as a whole revealed no significant correlation between the variables, with…

  17. Union, States Wage Frontal Attack on NCLB

    ERIC Educational Resources Information Center

    Keller, Bess; Sack, Joetta L.

    2005-01-01

    Widespread sniping at the Bush administration's centerpiece education law escalated into a frontal attack as the nation's largest teachers' union. Several school districts sued federal officials over the measure, just a day after the Utah legislature approved a bill challenging the reach of the law. The National Education Association's suit…

  18. Adversarial Feature Selection Against Evasion Attacks.

    PubMed

    Zhang, Fei; Chan, Patrick P K; Biggio, Battista; Yeung, Daniel S; Roli, Fabio

    2016-03-01

    Pattern recognition and machine learning techniques have been increasingly adopted in adversarial settings such as spam, intrusion, and malware detection, although their security against well-crafted attacks that aim to evade detection by manipulating data at test time has not yet been thoroughly assessed. While previous work has been mainly focused on devising adversary-aware classification algorithms to counter evasion attempts, only few authors have considered the impact of using reduced feature sets on classifier security against the same attacks. An interesting, preliminary result is that classifier security to evasion may be even worsened by the application of feature selection. In this paper, we provide a more detailed investigation of this aspect, shedding some light on the security properties of feature selection against evasion attacks. Inspired by previous work on adversary-aware classifiers, we propose a novel adversary-aware feature selection model that can improve classifier security against evasion attacks, by incorporating specific assumptions on the adversary's data manipulation strategy. We focus on an efficient, wrapper-based implementation of our approach, and experimentally validate its soundness on different application examples, including spam and malware detection.

  19. Recovery of human remains after shark attack.

    PubMed

    Byard, Roger W; James, Ross A; Heath, Karen J

    2006-09-01

    Two cases of fatal shark attack are reported where the only tissues recovered were fragments of lung. Case 1: An 18-year-old male who was in the sea behind a boat was observed by friends to be taken by a great white shark (Carcharodon carcharias). The shark dragged him under the water and then, with a second shark, dismembered the body. Witnesses noted a large amount of blood and unrecognizable body parts coming to the surface. The only tissues recovered despite an intensive beach and sea search were 2 fragments of lung. Case 2: A 19-year-old male was attacked by a great white shark while diving. A witness saw the shark swim away with the victim's body in its mouth. Again, despite intensive beach and sea searches, the only tissue recovered was a single piece of lung, along with pieces of wetsuit and diving equipment. These cases indicate that the only tissue to escape being consumed or lost in fatal shark attacks, where there is a significant attack with dismemberment and disruption of the integrity of the body, may be lung. The buoyancy of aerated pulmonary tissue ensures that it rises quickly to the surface, where it may be recovered by searchers soon after the attack. Aeration of the lung would be in keeping with death from trauma rather than from drowning and may be a useful marker in unwitnessed deaths to separate ante- from postmortem injury, using only relatively small amounts of tissues. Early organ recovery enhances the identification of human tissues as the extent of morphologic alterations by putrefactive processes and sea scavengers will have been minimized. DNA testing is also possible on such recovered fragments, enabling confirmation of the identity of the victim.

  20. Hope, Meaning, and Growth Following the September 11, 2001, Terrorist Attacks

    ERIC Educational Resources Information Center

    Ai, Amy; Cascio, Toni; Santangelo, Linda K.; Evans-Campbell, Teresa

    2005-01-01

    Positive psychologists found the increase of seven character strengths that encompass the so-called theological virtues, including hope and spirituality, in Americans after the September 11, 2001, attacks. Little is known about how they may affect post-September 11, 2001, mental health. Using multivariate analysis, this study investigated the…

  1. Nonlinear optical cryptosystem resistant to standard and hybrid attacks

    NASA Astrophysics Data System (ADS)

    Sinha, Aloka

    2016-06-01

    We propose a nonlinear optical cryptosystem that is resistant to amplitude-phase retrieval attacks, known-plaintext attack and chosen-plaintext attack. A squaring operation is introduced in the encryption path, which thwarts the iterative attacks. This nonlinear operation tends to amplify the error in the estimation during an iterative attack. The decryption process requires the use of a square-root operation. Thus, in the reverse path also, the attacks encounter the nonlinear square-root operation. These two nonlinearities make the iterative attacks unstable, thereby leading to non-convergence of the mean square error (MSE). Our technique is also resistant to hybrid attacks. The technique is general and is shown to work on a variety of images of the type grayscale and binary. Numerical simulation results corroborate the effectiveness of the proposed cryptosystem.

  2. Heart Attack Before 50 Ups Early Death Risk

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_160692.html Heart Attack Before 50 Ups Early Death Risk But healthy ... News) -- The risk of early death after a heart attack has lessened over the past 30 years among ...

  3. Anger, Heavy Exertion: Fast Track to A Heart Attack?

    MedlinePlus

    ... html Anger, Heavy Exertion: Fast Track to a Heart Attack? But researchers suggest that artery-clogging plaque has ... physical exertion may be triggers for a first heart attack in some people, new research suggests. In the ...

  4. Poorer Heart Attack Victims, Especially Women, Fare Worse: Study

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_161722.html Poorer Heart Attack Victims, Especially Women, Fare Worse: Study Doctors need ... 2016 THURSDAY, Oct. 27, 2016 (HealthDay News) -- Younger heart attack survivors who struggle to afford health care and ...

  5. Expected versus unexpected panic attacks: a naturalistic prospective study.

    PubMed

    Kenardy, J; Taylor, C B

    1999-01-01

    The purpose of this study was to identify factors that are associated with expectation of panic attacks as well as to validate the hypothesized tendency to identify false (panic) alarms in panic disorder. Ten women with panic disorder were assessed naturalistically using computer-assisted self-monitoring. This allowed for prospective assessment of expected versus unexpected panic attacks. Expectation of panic attacks was associated with panic occurrence, as well as elevated sense of threat or danger, anxiety, helplessness, avoidance, distress about physical symptoms, physical sensations, and catastrophic thoughts prior to the attack. In general, the state measured prior to unexpected attacks did not differ from ongoing nonpanic state. Furthermore, none of the variables measured during the attacks were able to distinguish unexpected attacks from expected attacks.

  6. Two fatal tiger attacks in zoos.

    PubMed

    Tantius, Britta; Wittschieber, Daniel; Schmidt, Sven; Rothschild, Markus A; Banaschak, Sibylle

    2016-01-01

    Two captive tiger attacks are presented that took place in Cologne and Münster zoos. Both attacks occurred when the handlers, intent on cleaning the enclosures, entered whilst the tigers accidently retained access to the location, and thus defended their territory against the perceived intruders. Both victims suffered fatal neck injuries from the bites. At Münster, colleagues managed to lure the tiger away from its victim to enable treatment, whilst the Cologne zoo tiger had to be shot in order to allow access to be gained. Whilst it was judged that human error led to the deaths of the experienced zookeepers, the investigation in Münster was closed as no third party was found to be at fault, whereas the Cologne zoo director was initially charged with being negligent. These charges were subsequently dismissed as safety regulations were found to be up to date.

  7. Cascade-based attacks on complex networks

    NASA Astrophysics Data System (ADS)

    Motter, Adilson E.; Lai, Ying-Cheng

    2002-12-01

    We live in a modern world supported by large, complex networks. Examples range from financial markets to communication and transportation systems. In many realistic situations the flow of physical quantities in the network, as characterized by the loads on nodes, is important. We show that for such networks where loads can redistribute among the nodes, intentional attacks can lead to a cascade of overload failures, which can in turn cause the entire or a substantial part of the network to collapse. This is relevant for real-world networks that possess a highly heterogeneous distribution of loads, such as the Internet and power grids. We demonstrate that the heterogeneity of these networks makes them particularly vulnerable to attacks in that a large-scale cascade may be triggered by disabling a single key node. This brings obvious concerns on the security of such systems.

  8. Satellite Threat Warning and Attack Reporting

    SciTech Connect

    Hilland, D.; Phipps, G.; Jingle, C.; Newton, G.

    1997-12-31

    The Air Force Research Laboratory`s Satellite Threat Warning and Attack Reporting (STW/AR) program will provide technologies for advanced threat warning and reporting of radio frequency (RF) and laser threats. The STW/AR program objectives are: (a) develop cost- effective technologies to detect, identify, locate, characterize, and report attacks or interference against U.S. and Allied satellites. (b) demonstrate innovative, light-weight, low-power, laser and RF sensors. The program focuses on the demonstration of RF and laser sensors. The RF sensor effort includes the investigation of interferometric antenna arrays, multi-arm spiral and butler matrix antennas, wideband receivers, adaptive processors, and improved processing algorithms. The laser sensor effort includes the investigation of alternative detectors, broadband grating and optical designs, active pixel sensing, and improved processing algorithms.

  9. Cell phone camera ballistics: attacks and countermeasures

    NASA Astrophysics Data System (ADS)

    Steinebach, Martin; Liu, Huajian; Fan, Peishuai; Katzenbeisser, Stefan

    2010-01-01

    Multimedia forensics deals with the analysis of multimedia data to gather information on its origin and authenticity. One therefore needs to distinguish classical criminal forensics (which today also uses multimedia data as evidence) and multimedia forensics where the actual case is based on a media file. One example for the latter is camera forensics where pixel error patters are used as fingerprints identifying a camera as the source of an image. Of course multimedia forensics can become a tool for criminal forensics when evidence used in a criminal investigation is likely to be manipulated. At this point an important question arises: How reliable are these algorithms? Can a judge trust their results? How easy are they to manipulate? In this work we show how camera forensics can be attacked and introduce a potential countermeasure against these attacks.

  10. Making MANET secured against malicious attack

    NASA Astrophysics Data System (ADS)

    Kush, Ashwani; Taneja, Sunil; Kush, Shagun

    2011-12-01

    A Mobile Adhoc Network (MANET) is characterized by mobile nodes, multihop wireless connectivity, infrastructureless environment and dynamic topology. A recent trend in Ad Hoc network routing is the reactive ondemand philosophy where routes are established only when required. Stable Routing is of major concern in Ad hoc routing. Security and Power efficiency are the major concerns in this field. This paper is an effort to use security to achieve more reliable routing. The ad hoc environment is accessible to both legitimate network users and malicious attackers. The proposed scheme is intended to incorporate security aspect on existing protocols. The study will help in making protocol more robust against attacks to achieve stable routing in routing protocols.

  11. RISK DISCLOSURE AGAINST ATTACK ON CRITICAL INFRASTRUCTURES

    NASA Astrophysics Data System (ADS)

    Yoshida, Mamoru; Kobayashi, Kiyoshi

    This paper analyzes the government's defensive and disclosure strategies to reduce the damage caused by terrorists that attack critical infrastructures using subjective game theory. The government recognizes a terrorist as a hidden opponent and the government's decision making about the policies against terror attacks depends on the belief about the existence of terrorist. In addition, it is not necessarily true that the government and the terrorist play the common game and make their decisions. Considering these points, the paper formulates the model in which the government and the terrorist formulate the subjective games respectively, and they induce the strategies using the equilibriums of their subjective games. The paper concluded that the government's disclosure about the implementation of the countermeasure, rather than the disclosure of warning level related with the belief about the existence of terrorist, brings about the higher increment of the subjective payoffs of the government.

  12. Comparison of Angle of Attack Measurements for Wind Tunnel Testing

    NASA Technical Reports Server (NTRS)

    Jones, Thomas, W.; Hoppe, John C.

    2001-01-01

    Two optical systems capable of measuring model attitude and deformation were compared to inertial devices employed to acquire wind tunnel model angle of attack measurements during the sting mounted full span 30% geometric scale flexible configuration of the Northrop Grumman Unmanned Combat Air Vehicle (UCAV) installed in the NASA Langley Transonic Dynamics Tunnel (TDT). The overall purpose of the test at TDT was to evaluate smart materials and structures adaptive wing technology. The optical techniques that were compared to inertial devices employed to measure angle of attack for this test were: (1) an Optotrak (registered) system, an optical system consisting of two sensors, each containing a pair of orthogonally oriented linear arrays to compute spatial positions of a set of active markers; and (2) Video Model Deformation (VMD) system, providing a single view of passive targets using a constrained photogrammetric solution whose primary function was to measure wing and control surface deformations. The Optotrak system was installed for this test for the first time at TDT in order to assess the usefulness of the system for future static and dynamic deformation measurements.

  13. Securing iris recognition systems against masquerade attacks

    NASA Astrophysics Data System (ADS)

    Galbally, Javier; Gomez-Barrero, Marta; Ross, Arun; Fierrez, Julian; Ortega-Garcia, Javier

    2013-05-01

    A novel two-stage protection scheme for automatic iris recognition systems against masquerade attacks carried out with synthetically reconstructed iris images is presented. The method uses different characteristics of real iris images to differentiate them from the synthetic ones, thereby addressing important security flaws detected in state-of-the-art commercial systems. Experiments are carried out on the publicly available Biosecure Database and demonstrate the efficacy of the proposed security enhancing approach.

  14. Trichobothrial mediation of an aquatic escape response: directional jumps by the fishing spider, Dolomedes triton, foil frog attacks.

    PubMed

    Suter, Robert B

    2003-01-01

    Fishing spiders (Pisauridae) frequent the surfaces of ponds and streams and thereby expose themselves to predation by a variety of aquatic and semi-aquatic vertebrates. To assess the possibility that the impressive jumps of fishing spiders from the water surface function in evading attacks by frogs, attacks by bullfrogs (Rana catesbiana) and green frogs (R. clamitans) on Dolomedes triton were studied. Both the attack dynamics of the frogs and the evasive behaviors of the spiders were recorded at 250 frames per second. A freeze-dried bullfrog, propelled toward spiders with acceleration, posture, and position that approximated the natural attack posture and dynamics, was used to assess the spiders' behavior. Qualitatively, the spiders responded to these mock-attacks just as they had to attacks by live frogs: jumping (N=29 jumps, 56.9% of instances), rearing the legs nearest the attacking frog (N=15, 29.4%), or showing no visible response (N=7, 13.7%). Spiders that jumped always did so away (in the vertical plane) from the attack (mean =137 degrees vs. vertical at 90 degrees or horizontally toward the frog at 0 degrees ). The involvement of the trichobothria (leg hairs sensitive to air movements), and the eyes as sensory mediators of the evasion response was assessed. Spiders with deactivated trichobothria were significantly impaired relative to intact and sham-deactivated spiders, and relative to spiders in total darkness. Thus, functional trichobothria, unlike the eyes, are both necessary and sufficient mediators of the evasion response. Measurements of air flow during frog attacks suggest that an exponential rise in flow velocity is the airborne signature of an attack. PMID:15841235

  15. Trichobothrial mediation of an aquatic escape response: Directional jumps by the fishing spider, Dolomedes triton, foil frog attacks

    PubMed Central

    Suter, Robert. B.

    2003-01-01

    Fishing spiders (Pisauridae) frequent the surfaces of ponds and streams and thereby expose themselves to predation by a variety of aquatic and semi-aquatic vertebrates. To assess the possibility that the impressive jumps of fishing spiders from the water surface function in evading attacks by frogs, attacks by bullfrogs (Rana catesbiana) and green frogs (R. clamitans) on Dolomedes triton were studied. Both the attack dynamics of the frogs and the evasive behaviors of the spiders were recorded at 250 frames per second. A freeze-dried bullfrog, propelled toward spiders with acceleration, posture, and position that approximated the natural attack posture and dynamics, was used to assess the spiders' behavior. Qualitatively, the spiders responded to these mock-attacks just as they had to attacks by live frogs: jumping (N=29 jumps, 56.9% of instances), rearing the legs nearest the attacking frog (N=15, 29.4%), or showing no visible response (N=7, 13.7%). Spiders that jumped always did so away (in the vertical plane) from the attack (mean =137° vs. vertical at 90° or horizontally toward the frog at 0°). The involvement of the trichobothria (leg hairs sensitive to air movements), and the eyes as sensory mediators of the evasion response was assessed. Spiders with deactivated trichobothria were significantly impaired relative to intact and sham-deactivated spiders, and relative to spiders in total darkness. Thus, functional trichobothria, unlike the eyes, are both necessary and sufficient mediators of the evasion response. Measurements of air flow during frog attacks suggest that an exponential rise in flow velocity is the airborne signature of an attack. Abbreviation: a acceleration (m s−2) fps frames per second HS high-speed video v velocity (m s−1) PMID:15841235

  16. Enhancing network robustness against malicious attacks

    NASA Astrophysics Data System (ADS)

    Zeng, An; Liu, Weiping

    2012-06-01

    In a recent work [Schneider , Proc. Natl. Acad. Sci. USAPNASA60027-842410.1073/pnas.1009440108 108, 3838 (2011)], the authors proposed a simple measure for network robustness under malicious attacks on nodes. Using a greedy algorithm, they found that the optimal structure with respect to this quantity is an onion structure in which high-degree nodes form a core surrounded by rings of nodes with decreasing degree. However, in real networks the failure can also occur in links such as dysfunctional power cables and blocked airlines. Accordingly, complementary to the node-robustness measurement (Rn), we propose a link-robustness index (Rl). We show that solely enhancing Rn cannot guarantee the improvement of Rl. Moreover, the structure of an Rl-optimized network is found to be entirely different from that of an onion network. In order to design robust networks that are resistant to a more realistic attack condition, we propose a hybrid greedy algorithm that takes both the Rn and Rl into account. We validate the robustness of our generated networks against malicious attacks mixed with both nodes and links failure. Finally, some economical constraints for swapping the links in real networks are considered, and significant improvement in both aspects of robustness is still achieved.

  17. Enhancing network robustness against malicious attacks.

    PubMed

    Zeng, An; Liu, Weiping

    2012-06-01

    In a recent work [Schneider et al., Proc. Natl. Acad. Sci. USA 108, 3838 (2011)], the authors proposed a simple measure for network robustness under malicious attacks on nodes. Using a greedy algorithm, they found that the optimal structure with respect to this quantity is an onion structure in which high-degree nodes form a core surrounded by rings of nodes with decreasing degree. However, in real networks the failure can also occur in links such as dysfunctional power cables and blocked airlines. Accordingly, complementary to the node-robustness measurement (R(n)), we propose a link-robustness index (R(l)). We show that solely enhancing R(n) cannot guarantee the improvement of R(l). Moreover, the structure of an R(l)-optimized network is found to be entirely different from that of an onion network. In order to design robust networks that are resistant to a more realistic attack condition, we propose a hybrid greedy algorithm that takes both the R(n) and R(l) into account. We validate the robustness of our generated networks against malicious attacks mixed with both nodes and links failure. Finally, some economical constraints for swapping the links in real networks are considered, and significant improvement in both aspects of robustness is still achieved.

  18. Sulfate attack on cement-stabilized sand

    SciTech Connect

    Rollings, R.S.; Burkes, J.P.; Rollings, M.P.

    1999-05-01

    A 3.5-km (2.2 mi) section of a road in Georgia developed unexpected transverse bumps within 6 months after construction. The source of the bumps appeared to be expansion within the cement-stabilized base course. Laboratory examination of samples from areas showing distress revealed the presence of ettringite, a calcium sulfoaluminate the formation of which can be accompanied by severe expansion. This expansive materials was the probable cause of the volume changes causing the transverse bumps. The calcium and alumina needed to form ettringite ware available from the portland cement and the stabilized soil`s clay minerals. The source of the sulfur was identified as the well water that was mixed with the cement-stabilized base. Sulfate attack of cement-stabilized soils is a relatively infrequent problem, but it is highly destructive when it occurs. Currently, there are no firm criteria for identifying when sulfate attack of a cement-stabilized soil is a potential problem nor are there established methods of preventing the attack.

  19. Enhancing network robustness against malicious attacks.

    PubMed

    Zeng, An; Liu, Weiping

    2012-06-01

    In a recent work [Schneider et al., Proc. Natl. Acad. Sci. USA 108, 3838 (2011)], the authors proposed a simple measure for network robustness under malicious attacks on nodes. Using a greedy algorithm, they found that the optimal structure with respect to this quantity is an onion structure in which high-degree nodes form a core surrounded by rings of nodes with decreasing degree. However, in real networks the failure can also occur in links such as dysfunctional power cables and blocked airlines. Accordingly, complementary to the node-robustness measurement (R(n)), we propose a link-robustness index (R(l)). We show that solely enhancing R(n) cannot guarantee the improvement of R(l). Moreover, the structure of an R(l)-optimized network is found to be entirely different from that of an onion network. In order to design robust networks that are resistant to a more realistic attack condition, we propose a hybrid greedy algorithm that takes both the R(n) and R(l) into account. We validate the robustness of our generated networks against malicious attacks mixed with both nodes and links failure. Finally, some economical constraints for swapping the links in real networks are considered, and significant improvement in both aspects of robustness is still achieved. PMID:23005185

  20. Systematic Poisoning Attacks on and Defenses for Machine Learning in Healthcare.

    PubMed

    Mozaffari-Kermani, Mehran; Sur-Kolay, Susmita; Raghunathan, Anand; Jha, Niraj K

    2015-11-01

    Machine learning is being used in a wide range of application domains to discover patterns in large datasets. Increasingly, the results of machine learning drive critical decisions in applications related to healthcare and biomedicine. Such health-related applications are often sensitive, and thus, any security breach would be catastrophic. Naturally, the integrity of the results computed by machine learning is of great importance. Recent research has shown that some machine-learning algorithms can be compromised by augmenting their training datasets with malicious data, leading to a new class of attacks called poisoning attacks. Hindrance of a diagnosis may have life-threatening consequences and could cause distrust. On the other hand, not only may a false diagnosis prompt users to distrust the machine-learning algorithm and even abandon the entire system but also such a false positive classification may cause patient distress. In this paper, we present a systematic, algorithm-independent approach for mounting poisoning attacks across a wide range of machine-learning algorithms and healthcare datasets. The proposed attack procedure generates input data, which, when added to the training set, can either cause the results of machine learning to have targeted errors (e.g., increase the likelihood of classification into a specific class), or simply introduce arbitrary errors (incorrect classification). These attacks may be applied to both fixed and evolving datasets. They can be applied even when only statistics of the training dataset are available or, in some cases, even without access to the training dataset, although at a lower efficacy. We establish the effectiveness of the proposed attacks using a suite of six machine-learning algorithms and five healthcare datasets. Finally, we present countermeasures against the proposed generic attacks that are based on tracking and detecting deviations in various accuracy metrics, and benchmark their effectiveness.

  1. Formation of asymmetric separated flow past slender bodies of revolution at large angles of attack

    NASA Technical Reports Server (NTRS)

    Goman, M. G.; Khrabrov, A. N.

    1986-01-01

    The paper examines the problem of determining stationary positions of pairs of vortices of unequal intensity in the flow behind a cylinder modeling the axisymmetric separated flow past a slender body at large angles of attack. The possible asymmetric stationary positions of two vortices are calculated, and their stability with respect to small perturbations is determined. Bifurcations of the flow field with changes in vortex intensity are analyzed.

  2. Attributing heart attack and stroke to "Old Age": Implications for subsequent health outcomes among older adults.

    PubMed

    Stewart, Tara L; Chipperfield, Judith G; Perry, Raymond P; Hamm, Jeremy M

    2016-01-01

    This study assessed the extent to which older adults attribute a recent heart attack/stroke to "old age," and examined consequences for subsequent lifestyle behavior and health-care service utilization. Community-dwelling adults (N = 57, ages 73-98 years) were interviewed about their heart attack/stroke, and an objective health registry provided data on health-care utilization over a 3-year period. Endorsement of "old age" as a cause of heart attack/stroke negatively predicted lifestyle behavior change, and positively predicted frequency of physician visits and likelihood of hospitalization over the subsequent 3 years. Findings suggest the importance of considering "old age" attributions in the context of cardiovascular health events.

  3. New Attacks on RSA with Modulus N = p2q Using Continued Fractions

    NASA Astrophysics Data System (ADS)

    Asbullah, M. A.; Ariffin, M. R. K.

    2015-06-01

    In this paper, we propose two new attacks on RSA with modulus N = p2q using continued fractions. Our first attack is based on the RSA key equation ed - ϕ(N)k = 1 where ϕ(N) = p(p - 1)(q - 1). Assuming that and , we show that can be recovered among the convergents of the continued fraction expansion of . Our second attack is based on the equation eX - (N - (ap2 + bq2)) Y = Z where a,b are positive integers satisfying gcd(a,b) = 1, |ap2 - bq2| < N1/2 and ap2 + bq2 = N2/3+α with 0 < α < 1/3. Given the conditions , we show that one can factor N = p2q in polynomial time.

  4. Assessing Terrorist Motivations for Attacking Critical Infrastructure

    SciTech Connect

    Ackerman, G; Abhayaratne, P; Bale, J; Bhattacharjee, A; Blair, C; Hansell, L; Jayne, A; Kosal, M; Lucas, S; Moran, K; Seroki, L; Vadlamudi, S

    2006-12-04

    Certain types of infrastructure--critical infrastructure (CI)--play vital roles in underpinning our economy, security and way of life. These complex and often interconnected systems have become so ubiquitous and essential to day-to-day life that they are easily taken for granted. Often it is only when the important services provided by such infrastructure are interrupted--when we lose easy access to electricity, health care, telecommunications, transportation or water, for example--that we are conscious of our great dependence on these networks and of the vulnerabilities that stem from such dependence. Unfortunately, it must be assumed that many terrorists are all too aware that CI facilities pose high-value targets that, if successfully attacked, have the potential to dramatically disrupt the normal rhythm of society, cause public fear and intimidation, and generate significant publicity. Indeed, revelations emerging at the time of this writing about Al Qaida's efforts to prepare for possible attacks on major financial facilities in New York, New Jersey, and the District of Columbia remind us just how real and immediate such threats to CI may be. Simply being aware that our nation's critical infrastructure presents terrorists with a plethora of targets, however, does little to mitigate the dangers of CI attacks. In order to prevent and preempt such terrorist acts, better understanding of the threats and vulnerabilities relating to critical infrastructure is required. The Center for Nonproliferation Studies (CNS) presents this document as both a contribution to the understanding of such threats and an initial effort at ''operationalizing'' its findings for use by analysts who work on issues of critical infrastructure protection. Specifically, this study focuses on a subsidiary aspect of CI threat assessment that has thus far remained largely unaddressed by contemporary terrorism research: the motivations and related factors that determine whether a terrorist

  5. Trojan-horse attacks threaten the security of practical quantum cryptography

    NASA Astrophysics Data System (ADS)

    Jain, Nitin; Anisimova, Elena; Khan, Imran; Makarov, Vadim; Marquardt, Christoph; Leuchs, Gerd

    2014-12-01

    A quantum key distribution (QKD) system may be probed by an eavesdropper Eve by sending in bright light from the quantum channel and analyzing the back-reflections. We propose and experimentally demonstrate a setup for mounting such a Trojan-horse attack. We show it in operation against the quantum cryptosystem Clavis2 from ID Quantique, as a proof-of-principle. With just a few back-reflected photons, Eve discerns Bob's (secret) basis choice, and thus the raw key bit in the Scarani-Acín-Ribordy-Gisin 2004 protocol, with higher than 90% probability. This would clearly breach the security of the cryptosystem. Unfortunately, Eve's bright pulses have a side effect of causing a high level of afterpulsing in Bob's single-photon detectors, resulting in a large quantum bit error rate that effectively protects this system from our attack. However, in a Clavis2-like system equipped with detectors with less-noisy but realistic characteristics, an attack strategy with positive leakage of the key would exist. We confirm this by a numerical simulation. Both the eavesdropping setup and strategy can be generalized to attack most of the current QKD systems, especially if they lack proper safeguards. We also propose countermeasures to prevent such attacks.

  6. On the routing protocol influence on the resilience of wireless sensor networks to jamming attacks.

    PubMed

    Del-Valle-Soto, Carolina; Mex-Perera, Carlos; Monroy, Raul; Nolazco-Flores, Juan Arturo

    2015-03-27

    In this work, we compare a recently proposed routing protocol, the multi-parent hierarchical (MPH) protocol, with two well-known protocols, the ad hoc on-demand distance vector (AODV) and dynamic source routing (DSR). For this purpose, we have developed a simulator, which faithfully reifies the workings of a given protocol, considering a fixed, reconfigurable ad hoc network given by the number and location of participants, and general network conditions. We consider a scenario that can be found in a large number of wireless sensor network applications, a single sink node that collects all of the information generated by the sensors. The metrics used to compare the protocols were the number of packet retransmissions, carrier sense multiple access (CSMA) inner loop retries, the number of nodes answering the queries from the coordinator (sink) node and the energy consumption. We tested the network under ordinary (without attacks) conditions (and combinations thereof) and when it is subject to different types of jamming attacks (in particular, random and reactive jamming attacks), considering several positions for the jammer. Our results report that MPH has a greater ability to tolerate such attacks than DSR and AODV, since it minimizes and encapsulates the network segment under attack. The self-configuring capabilities of MPH derived from a combination of a proactive routes update, on a periodic-time basis, and a reactive behavior provide higher resilience while offering a better performance (overhead and energy consumption) than AODV and DSR, as shown in our simulation results.

  7. On the Routing Protocol Influence on the Resilience of Wireless Sensor Networks to Jamming Attacks

    PubMed Central

    Del-Valle-Soto, Carolina; Mex-Perera, Carlos; Monroy, Raul; Nolazco-Flores, Juan Arturo

    2015-01-01

    In this work, we compare a recently proposed routing protocol, the multi-parent hierarchical (MPH) protocol, with two well-known protocols, the ad hoc on-demand distance vector (AODV) and dynamic source routing (DSR). For this purpose, we have developed a simulator, which faithfully reifies the workings of a given protocol, considering a fixed, reconfigurable ad hoc network given by the number and location of participants, and general network conditions. We consider a scenario that can be found in a large number of wireless sensor network applications, a single sink node that collects all of the information generated by the sensors. The metrics used to compare the protocols were the number of packet retransmissions, carrier sense multiple access (CSMA) inner loop retries, the number of nodes answering the queries from the coordinator (sink) node and the energy consumption. We tested the network under ordinary (without attacks) conditions (and combinations thereof) and when it is subject to different types of jamming attacks (in particular, random and reactive jamming attacks), considering several positions for the jammer. Our results report that MPH has a greater ability to tolerate such attacks than DSR and AODV, since it minimizes and encapsulates the network segment under attack. The self-configuring capabilities of MPH derived from a combination of a proactive routes update, on a periodic-time basis, and a reactive behavior provide higher resilience while offering a better performance (overhead and energy consumption) than AODV and DSR, as shown in our simulation results. PMID:25825979

  8. Aerodynamic Loads on Tails at High Angles of Attack and Sideslip

    NASA Technical Reports Server (NTRS)

    Polhamus, E. C.; Spahr, J. R.

    1957-01-01

    Results are presented for the loads and moments acting on the individual tail surfaces of a body-tail combination over a wide range of angles of attack and sideslip. The effects of forebody length and panel-panel interference on the characteristics are included. It is shown that large nonlinear variations in these loads and moments, which occur at some combinations of angle of attack and sideslip, cannot be predicted by low-angle theory. A relatively simple, but general, theoretical method for calculating these load and moment characteristics is described, and the results from this method are found to be in good agreement with experiment provided the initial positions of the forebody vortices are known. It is shown that a simple application of slender-body theory can be used to predict the side loads due to sideslip that are contributed by a vertical tail on a wide variety of wing-body-tail combinations at low angles of attack. For several configurations, changes are indicated which reduced the vertical-tail loads per unit yawing moment of each complete configuration at large angles of attack. Some results are presented on the effect of high angle of attack on the induced-flow field and tail loads due to a wing at supersonic speed.

  9. Attack or retreat: contrasted defensive tactics used by Cyprian honeybee colonies under attack from hornets.

    PubMed

    Papachristoforou, Alexandros; Rortais, Agnès; Sueur, Jérôme; Arnold, Gérard

    2011-02-01

    This study describes the tactics used by Cyprian honeybees (Apis mellifera cypria) to defend their colonies against hornet (Vespa orientalis orientalis) attacks. We use simulated hornet attacks and a combination of video recordings and image analysis to reveal, for the first time, contrasted intra-subspecies defensive tactics that operate at the colony level during predation. In some colonies, when attacked, the numbers of guards at the hive entrance increases rapidly to attack, engulf, and kill invading hornets. In other colonies, guards avoid conflicts with hornets by retreating gradually and by forming a defensive line of honeybees at the hive entrance. Retreater colonies have propolis walls at the hive entrances with small apertures that are too narrow to allow the hornet to access the hive and that therefore reinforces entrance protection. On the contrary, attacker colonies have propolis walls with large openings through which the hornet can pass; these bees block the hornet's access by intensively guarding the hive entrance. We experimentally destroy propolis walls to test whether colonies consistently rebuild walls with the same intrinsic characteristics and we also monitor the survival rate of each anti-predator tactic after massive natural predation by hornets.

  10. A common fold mediates vertebrate defense and bacterial attack.

    PubMed

    Rosado, Carlos J; Buckle, Ashley M; Law, Ruby H P; Butcher, Rebecca E; Kan, Wan-Ting; Bird, Catherina H; Ung, Kheng; Browne, Kylie A; Baran, Katherine; Bashtannyk-Puhalovich, Tanya A; Faux, Noel G; Wong, Wilson; Porter, Corrine J; Pike, Robert N; Ellisdon, Andrew M; Pearce, Mary C; Bottomley, Stephen P; Emsley, Jonas; Smith, A Ian; Rossjohn, Jamie; Hartland, Elizabeth L; Voskoboinik, Ilia; Trapani, Joseph A; Bird, Phillip I; Dunstone, Michelle A; Whisstock, James C

    2007-09-14

    Proteins containing membrane attack complex/perforin (MACPF) domains play important roles in vertebrate immunity, embryonic development, and neural-cell migration. In vertebrates, the ninth component of complement and perforin form oligomeric pores that lyse bacteria and kill virus-infected cells, respectively. However, the mechanism of MACPF function is unknown. We determined the crystal structure of a bacterial MACPF protein, Plu-MACPF from Photorhabdus luminescens, to 2.0 angstrom resolution. The MACPF domain reveals structural similarity with poreforming cholesterol-dependent cytolysins (CDCs) from Gram-positive bacteria. This suggests that lytic MACPF proteins may use a CDC-like mechanism to form pores and disrupt cell membranes. Sequence similarity between bacterial and vertebrate MACPF domains suggests that the fold of the CDCs, a family of proteins important for bacterial pathogenesis, is probably used by vertebrates for defense against infection.

  11. A Common Fold Mediates Vertebrate Defense and Bacterial Attack

    SciTech Connect

    Rosado, Carlos J.; Buckle, Ashley M.; Law, Ruby H.P.; Butcher, Rebecca E.; Kan, Wan-Ting; Bird, Catherina H.; Ung, Kheng; Browne, Kylie A.; Baran, Katherine; Bashtannyk-Puhalovich, Tanya A.; Faux, Noel G.; Wong, Wilson; Porter, Corrine J.; Pike, Robert N.; Ellisdon, Andrew M.; Pearce, Mary C.; Bottomley, Stephen P.; Emsley, Jonas; Smith, A. Ian; Rossjohn, Jamie; Hartland, Elizabeth L.; Voskoboinik, Ilia; Trapani, Joseph A.; Bird, Phillip I.; Dunstone, Michelle A.; Whisstock, James C.

    2008-10-02

    Proteins containing membrane attack complex/perforin (MACPF) domains play important roles in vertebrate immunity, embryonic development, and neural-cell migration. In vertebrates, the ninth component of complement and perforin form oligomeric pores that lyse bacteria and kill virus-infected cells, respectively. However, the mechanism of MACPF function is unknown. We determined the crystal structure of a bacterial MACPF protein, Plu-MACPF from Photorhabdus luminescens, to 2.0 angstrom resolution. The MACPF domain reveals structural similarity with poreforming cholesterol-dependent cytolysins (CDCs) from Gram-positive bacteria. This suggests that lytic MACPF proteins may use a CDC-like mechanism to form pores and disrupt cell membranes. Sequence similarity between bacterial and vertebrate MACPF domains suggests that the fold of the CDCs, a family of proteins important for bacterial pathogenesis, is probably used by vertebrates for defense against infection.

  12. Efficient certificate-based signcryption secure against public key replacement attacks and insider attacks.

    PubMed

    Lu, Yang; Li, Jiguo

    2014-01-01

    Signcryption is a useful cryptographic primitive that achieves confidentiality and authentication in an efficient manner. As an extension of signcryption in certificate-based cryptography, certificate-based signcryption preserves the merits of certificate-based cryptography and signcryption simultaneously. In this paper, we present an improved security model of certificate-based signcryption that covers both public key replacement attack and insider security. We show that an existing certificate-based signcryption scheme is insecure in our model. We also propose a new certificate-based signcryption scheme that achieves security against both public key replacement attacks and insider attacks. We prove in the random oracle model that the proposed scheme is chosen-ciphertext secure and existentially unforgeable. Performance analysis shows that the proposed scheme outperforms all the previous certificate-based signcryption schemes in the literature.

  13. Efficient Certificate-Based Signcryption Secure against Public Key Replacement Attacks and Insider Attacks

    PubMed Central

    Li, Jiguo

    2014-01-01

    Signcryption is a useful cryptographic primitive that achieves confidentiality and authentication in an efficient manner. As an extension of signcryption in certificate-based cryptography, certificate-based signcryption preserves the merits of certificate-based cryptography and signcryption simultaneously. In this paper, we present an improved security model of certificate-based signcryption that covers both public key replacement attack and insider security. We show that an existing certificate-based signcryption scheme is insecure in our model. We also propose a new certificate-based signcryption scheme that achieves security against both public key replacement attacks and insider attacks. We prove in the random oracle model that the proposed scheme is chosen-ciphertext secure and existentially unforgeable. Performance analysis shows that the proposed scheme outperforms all the previous certificate-based signcryption schemes in the literature. PMID:24959606

  14. Machine Learning Methods for Attack Detection in the Smart Grid.

    PubMed

    Ozay, Mete; Esnaola, Inaki; Yarman Vural, Fatos Tunay; Kulkarni, Sanjeev R; Poor, H Vincent

    2016-08-01

    Attack detection problems in the smart grid are posed as statistical learning problems for different attack scenarios in which the measurements are observed in batch or online settings. In this approach, machine learning algorithms are used to classify measurements as being either secure or attacked. An attack detection framework is provided to exploit any available prior knowledge about the system and surmount constraints arising from the sparse structure of the problem in the proposed approach. Well-known batch and online learning algorithms (supervised and semisupervised) are employed with decision- and feature-level fusion to model the attack detection problem. The relationships between statistical and geometric properties of attack vectors employed in the attack scenarios and learning algorithms are analyzed to detect unobservable attacks using statistical learning methods. The proposed algorithms are examined on various IEEE test systems. Experimental analyses show that machine learning algorithms can detect attacks with performances higher than attack detection algorithms that employ state vector estimation methods in the proposed attack detection framework.

  15. Machine Learning Methods for Attack Detection in the Smart Grid.

    PubMed

    Ozay, Mete; Esnaola, Inaki; Yarman Vural, Fatos Tunay; Kulkarni, Sanjeev R; Poor, H Vincent

    2016-08-01

    Attack detection problems in the smart grid are posed as statistical learning problems for different attack scenarios in which the measurements are observed in batch or online settings. In this approach, machine learning algorithms are used to classify measurements as being either secure or attacked. An attack detection framework is provided to exploit any available prior knowledge about the system and surmount constraints arising from the sparse structure of the problem in the proposed approach. Well-known batch and online learning algorithms (supervised and semisupervised) are employed with decision- and feature-level fusion to model the attack detection problem. The relationships between statistical and geometric properties of attack vectors employed in the attack scenarios and learning algorithms are analyzed to detect unobservable attacks using statistical learning methods. The proposed algorithms are examined on various IEEE test systems. Experimental analyses show that machine learning algorithms can detect attacks with performances higher than attack detection algorithms that employ state vector estimation methods in the proposed attack detection framework. PMID:25807571

  16. Explosive attack: Lessons learned in Seyed Al Shohada mosque attack, April 2008, Shiraz, Iran

    PubMed Central

    Paydar, Shahram; Sharifian, Maryam; Parvaz, Shahram Boland; Abbasi, Hamid Reza; Moradian, Mohamad javad; Roozbeh, Jamshid; Nikghbalian, Saman; Sagheb, Mohammad Mahdi; Ghaffarpasand, Fariborz; Salehi, Oveis; Dehghani, Javad

    2012-01-01

    Introduction: The threat of explosive attacks has become a worldwide problem. Bombing is the preferred method of attacks. These attacks result in specific physical and psychiatric trauma. In this paper, we present an epidemiologic description of the physical injuries of patients who survived the explosive attack in Seyed Al Shohada mosque April 2008 Shiraz, Iran. Materials and Methods: All medical records of the patients admitted at Shiraz Hospitals on April 2008 due to Seyed Al Shohada mosque bombing attacks, Shiraz, Iran, were reviewed. Results: A total of 202 patients were referred to the hospitals over 24 h following the terrorist attack. One hundred sixty-four patients were admitted for short periods of observation (<24 h). Thirty-eight patients needed more than 1 day of hospitalization. The mean age of the patients was 26.2 (range 2 to 51) years. One hundred thirty-five (66.8%) patients were males. Twenty-six (12.8%) were children. Burn was the most prevalent cause of admission. Five (13.5%) patients needed chest tube insertion and eight (21%) needed skin grafts due to burn. Overall, 12 patients expired (5%). Three (25%) of them were children (2 and 6, and 11 years old). Mortality rate was significantly higher among the children than adults (P value <0.05). The most important cause of death was head trauma which was seen in five (41.6%) of the expired patients followed by burn (including air way burn) in four (33%), and internal bleeding in three (25%). Patients with head trauma had significantly a higher rate of mortality than other patients (P value <0.05). Discussion: Following a bombing attack, numerous victims were brought to the emergency unit suffering from a combination of multi-organ injuries caused by the blast, penetrating injuries caused by shrapnel and other debris, and burns. It is important for a physician to be familiar with the clinical features and treatments of explosive attacks victims. Early management of patients at the scene and

  17. LAN attack detection using Discrete Event Systems.

    PubMed

    Hubballi, Neminath; Biswas, Santosh; Roopa, S; Ratti, Ritesh; Nandi, Sukumar

    2011-01-01

    Address Resolution Protocol (ARP) is used for determining the link layer or Medium Access Control (MAC) address of a network host, given its Internet Layer (IP) or Network Layer address. ARP is a stateless protocol and any IP-MAC pairing sent by a host is accepted without verification. This weakness in the ARP may be exploited by malicious hosts in a Local Area Network (LAN) by spoofing IP-MAC pairs. Several schemes have been proposed in the literature to circumvent these attacks; however, these techniques either make IP-MAC pairing static, modify the existing ARP, patch operating systems of all the hosts etc. In this paper we propose a Discrete Event System (DES) approach for Intrusion Detection System (IDS) for LAN specific attacks which do not require any extra constraint like static IP-MAC, changing the ARP etc. A DES model is built for the LAN under both a normal and compromised (i.e., spoofed request/response) situation based on the sequences of ARP related packets. Sequences of ARP events in normal and spoofed scenarios are similar thereby rendering the same DES models for both the cases. To create different ARP events under normal and spoofed conditions the proposed technique uses active ARP probing. However, this probing adds extra ARP traffic in the LAN. Following that a DES detector is built to determine from observed ARP related events, whether the LAN is operating under a normal or compromised situation. The scheme also minimizes extra ARP traffic by probing the source IP-MAC pair of only those ARP packets which are yet to be determined as genuine/spoofed by the detector. Also, spoofed IP-MAC pairs determined by the detector are stored in tables to detect other LAN attacks triggered by spoofing namely, man-in-the-middle (MiTM), denial of service etc. The scheme is successfully validated in a test bed. PMID:20804980

  18. LAN attack detection using Discrete Event Systems.

    PubMed

    Hubballi, Neminath; Biswas, Santosh; Roopa, S; Ratti, Ritesh; Nandi, Sukumar

    2011-01-01

    Address Resolution Protocol (ARP) is used for determining the link layer or Medium Access Control (MAC) address of a network host, given its Internet Layer (IP) or Network Layer address. ARP is a stateless protocol and any IP-MAC pairing sent by a host is accepted without verification. This weakness in the ARP may be exploited by malicious hosts in a Local Area Network (LAN) by spoofing IP-MAC pairs. Several schemes have been proposed in the literature to circumvent these attacks; however, these techniques either make IP-MAC pairing static, modify the existing ARP, patch operating systems of all the hosts etc. In this paper we propose a Discrete Event System (DES) approach for Intrusion Detection System (IDS) for LAN specific attacks which do not require any extra constraint like static IP-MAC, changing the ARP etc. A DES model is built for the LAN under both a normal and compromised (i.e., spoofed request/response) situation based on the sequences of ARP related packets. Sequences of ARP events in normal and spoofed scenarios are similar thereby rendering the same DES models for both the cases. To create different ARP events under normal and spoofed conditions the proposed technique uses active ARP probing. However, this probing adds extra ARP traffic in the LAN. Following that a DES detector is built to determine from observed ARP related events, whether the LAN is operating under a normal or compromised situation. The scheme also minimizes extra ARP traffic by probing the source IP-MAC pair of only those ARP packets which are yet to be determined as genuine/spoofed by the detector. Also, spoofed IP-MAC pairs determined by the detector are stored in tables to detect other LAN attacks triggered by spoofing namely, man-in-the-middle (MiTM), denial of service etc. The scheme is successfully validated in a test bed.

  19. How to capture fish in a school? Effect of successive predator attacks on seabird feeding success.

    PubMed

    Thiebault, Andréa; Semeria, Magali; Lett, Christophe; Tremblay, Yann

    2016-01-01

    Prey aggregations, such as fish schools, attract numerous predators. This typically leads to the formation of multispecific groups of predators. These aggregations can be seen both as a place of increased competition and as a place of possible facilitation between predators. Consequently, the functional role of such predator-prey aggregation is uncertain, and its effect on individual feeding success is virtually unknown. Using underwater film footage of different predators feeding on fish schools during the sardine run in South Africa, we directly measured the in situ feeding success of individual Cape gannets Morus capensis in different foraging situations. We determined the types of Cape gannet attacks (direct plunge dive or plunge dive followed by underwater pursuit) and we measured the occurrences and timing of attacks from the different species (mostly Cape gannets and long-beaked common dolphins Delphinus capensis). We also estimated the size of the targeted fish schools. These observations were complemented with a simulation model to evaluate the cumulative effect of successive predator attacks on the prey aggregation structure. The probability to capture a fish in one feeding attempt by Cape gannets averaged 0·28. It was lower when gannets engaged in underwater prey pursuit after the plunge compared to direct plunge (0·13 vs. 0·36). We found no effect of the number of prey on gannets' feeding success. However, the timing and frequency of attacks influenced strongly and positively the feeding success of individuals. The probability to capture a fish was the lowest (0·16) when no attack occurred in the few seconds (1-15 s) prior to a dive and the highest (˜0·4, i.e. more than twice) when one or two attacks occurred during this time window. The simulation model showed that a prey aggregation disorganized just after an attack and that the maximum of disturbance was obtained a few seconds after the initiation of the successive attacks. Our study suggests

  20. Cardiogenic embolism producing crescendo transient ischemic attacks.

    PubMed

    Geraghty, Patrick J; Oak, Jack; Choi, Eric T

    2005-09-01

    Lateralizing, repetitive transient ischemic attacks are characteristic of symptomatic carotid bifurcation atherosclerotic plaques. We report a case in which a cardiogenic embolus, after lodging at the left carotid bifurcation, produced crescendo episodes of expressive aphasia and mild right upper extremity weakness. Complete neurological recovery was achieved following emergent carotid embolectomy and endarterectomy. This case demonstrates that the laminar nature of internal carotid blood flow may result in the localization of embolic events to a single region of the cerebral vasculature, regardless of the source lesion in the carotid artery. The role of endoluminal techniques in the diagnosis and management of such lesions is discussed.

  1. Bobcat attack on a cottontail rabbit

    USGS Publications Warehouse

    Biggins, D.E.; Biggins, D.M.

    2006-01-01

    We observed an attack by a bobcat (Lynx rufus) on a cottontail rabbit (Sylvilagus) that involved stealthy approach by the cat for >1 h, followed by a 12.3-s chase covering 116.0 m for the cat and 128.4 m for the rabbit. During the chase, the route of the cat from starting point to kill site was more direct than the semi-circular route of the rabbit. Stride lengths for the cat and total distance covered by the chase were longer than those previously reported for bobcats.

  2. Sulfate attack in lime-treated subbases

    SciTech Connect

    Day, D.C.; Salami, M.R.; Rollings, R.S.

    1995-06-01

    Sulfate-induced heave or buckling in pavements is the phenomenon that occurs when the calcium in various lime-based stabilizers combines with the alumina and sulfate present in clay to form calcium sulfoaluminate, or ettringite. Ettringite, a crystal, can grow between clay particles, pushing them apart and causing swelling in the soil. When this happens in pavement subbases, the resulting heaving may cause the pavement to rupture and fail, sometimes in a dramatic way. In this paper the authors examine the mechanism of sulfate attack, review some of the work done on this problem, and present some examples of pavement failures.

  3. Error and attack tolerance of complex networks

    NASA Astrophysics Data System (ADS)

    Albert, Réka; Jeong, Hawoong; Barabási, Albert-László

    2000-07-01

    Many complex systems display a surprising degree of tolerance against errors. For example, relatively simple organisms grow, persist and reproduce despite drastic pharmaceutical or environmental interventions, an error tolerance attributed to the robustness of the underlying metabolic network. Complex communication networks display a surprising degree of robustness: although key components regularly malfunction, local failures rarely lead to the loss of the global information-carrying ability of the network. The stability of these and other complex systems is often attributed to the redundant wiring of the functional web defined by the systems' components. Here we demonstrate that error tolerance is not shared by all redundant systems: it is displayed only by a class of inhomogeneously wired networks, called scale-free networks, which include the World-Wide Web, the Internet, social networks and cells. We find that such networks display an unexpected degree of robustness, the ability of their nodes to communicate being unaffected even by unrealistically high failure rates. However, error tolerance comes at a high price in that these networks are extremely vulnerable to attacks (that is, to the selection and removal of a few nodes that play a vital role in maintaining the network's connectivity). Such error tolerance and attack vulnerability are generic properties of communication networks.

  4. Spontaneous subperiosteal hematoma precipitated by anxiety attack.

    PubMed

    Swanenberg, Irene M; Rizzuti, Allison E; Shinder, Roman

    2013-12-01

    A 60-year-old woman presented with diplopia and left periorbital edema and pressure, which developed during an anxiety attack the previous day. Examination revealed left inferotemporal globe dystopia, periorbital edema, ecchymosis, and limitation in supraduction. Orbital MRI confirmed the diagnosis of a superior subperiosteal orbital hematoma. The patient's signs and symptoms rapidly resolved with administration of oral corticosteroids. The patient remains asymptomatic with complete resolution of orbital signs at 3-month follow-up. Subperiosteal orbital hematoma (SOH) is a rare condition in which blood accumulates between the bony orbit and separated periosteum, and is often due to blunt head trauma. Non-traumatic SOH (NTSOH) is exceedingly rare and usually associated with known coagulopathies or tendency to bleed. However, few cases of spontaneous NTSOH have been reported without any such predisposition and are thought to be caused by sudden elevations in intrathoracic and intracranial venous pressure such as vomiting, coughing, SCUBA diving, weight lifting and labor. We herein describe the presentation, radiography and outcome of a unique case of spontaneous NTSOH following an anxiety attack. PMID:24063522

  5. Baiting Inside Attackers Using Decoy Documents

    NASA Astrophysics Data System (ADS)

    Bowen, Brian M.; Hershkop, Shlomo; Keromytis, Angelos D.; Stolfo, Salvatore J.

    The insider threat remains one of the most vexing problems in computer security. A number of approaches have been proposed to detect nefarious insider actions including user modeling and profiling techniques, policy and access enforcement techniques, and misuse detection. In this work we propose trap-based defense mechanisms and a deployment platform for addressing the problem of insiders attempting to exfiltrate and use sensitive information. The goal is to confuse and confound an adversary requiring more effort to identify real information from bogus information and provide a means of detecting when an attempt to exploit sensitive information has occurred. “Decoy Documents” are automatically generated and stored on a file system by the D3 System with the aim of enticing a malicious user. We introduce and formalize a number of properties of decoys as a guide to design trap-based defenses to increase the likelihood of detecting an insider attack. The decoy documents contain several different types of bogus credentials that when used, trigger an alert. We also embed “stealthy beacons” inside the documents that cause a signal to be emitted to a server indicating when and where the particular decoy was opened. We evaluate decoy documents on honeypots penetrated by attackers demonstrating the feasibility of the method.

  6. Spontaneous subperiosteal hematoma precipitated by anxiety attack.

    PubMed

    Swanenberg, Irene M; Rizzuti, Allison E; Shinder, Roman

    2013-12-01

    A 60-year-old woman presented with diplopia and left periorbital edema and pressure, which developed during an anxiety attack the previous day. Examination revealed left inferotemporal globe dystopia, periorbital edema, ecchymosis, and limitation in supraduction. Orbital MRI confirmed the diagnosis of a superior subperiosteal orbital hematoma. The patient's signs and symptoms rapidly resolved with administration of oral corticosteroids. The patient remains asymptomatic with complete resolution of orbital signs at 3-month follow-up. Subperiosteal orbital hematoma (SOH) is a rare condition in which blood accumulates between the bony orbit and separated periosteum, and is often due to blunt head trauma. Non-traumatic SOH (NTSOH) is exceedingly rare and usually associated with known coagulopathies or tendency to bleed. However, few cases of spontaneous NTSOH have been reported without any such predisposition and are thought to be caused by sudden elevations in intrathoracic and intracranial venous pressure such as vomiting, coughing, SCUBA diving, weight lifting and labor. We herein describe the presentation, radiography and outcome of a unique case of spontaneous NTSOH following an anxiety attack.

  7. Causal Attribution, Perceived Benefits, and Morbidity After a Heart Attack: An 8-Year Study.

    ERIC Educational Resources Information Center

    Affleck, Glenn; And Others

    1987-01-01

    Interviewed heart attack victims (N=287) seven weeks and eight years after their attack. Explored interrelations among causal attributions for the attack, survivor morbidity, and heart attack recurrence. Found that patients who cited benefits from their misfortune seven weeks after the first attack were less likely to have another attack and had…

  8. ScatterType: a reading CAPTCHA resistant to segmentation attack

    NASA Astrophysics Data System (ADS)

    Baird, Henry S.; Riopka, Terry P.

    2005-01-01

    A reading-based CAPTCHA designed to resist character-segmentation attacks, called 'ScatterType,' is described. Its challenges are pseudorandomly synthesized images of text strings rendered in machine-print typefaces: within each image, characters are fragmented using horizontal and vertical cuts, and the fragments are scattered by vertical and horizontal displacements. This scattering is designed to defeat all methods known to us for automatic segmentation into characters. As in the BaffleText CAPTCHA, English-like but unspellable text-strings are used to defend against known-dictionary attacks. In contrast to the PessimalPrint and BaffleText CAPTCHAs (and others), no physics-based image degradations, occlusions, or extraneous patterns are employed. We report preliminary results from a human legibility trial with 57 volunteers that yielded 4275 CAPTCHA challenges and responses. ScatterType human legibility remains remarkably high even on extremely degraded cases. We speculate that this is due to Gestalt perception abilities assisted by style-specific (here, typeface-specific) consistency among primitive shape features of character fragments. Although recent efforts to automate style-consistent perceptual skills have reported progress, the best known methods do not yet pose a threat to ScatterType. The experimental data also show that subjective rating of difficulty is strongly (and usefully) correlated with illegibility. In addition, we present early insights emerging from these data as we explore the ScatterType design space -- choice of typefaces, 'words', cut positioning, and displacements -- with the goal of locating regimes in which ScatterType challenges remain comfortably legible to almost all people but strongly resist mahine-vision methods for automatic segmentation into characters.

  9. ScatterType: a reading CAPTCHA resistant to segmentation attack

    NASA Astrophysics Data System (ADS)

    Baird, Henry S.; Riopka, Terry P.

    2004-12-01

    A reading-based CAPTCHA designed to resist character-segmentation attacks, called 'ScatterType,' is described. Its challenges are pseudorandomly synthesized images of text strings rendered in machine-print typefaces: within each image, characters are fragmented using horizontal and vertical cuts, and the fragments are scattered by vertical and horizontal displacements. This scattering is designed to defeat all methods known to us for automatic segmentation into characters. As in the BaffleText CAPTCHA, English-like but unspellable text-strings are used to defend against known-dictionary attacks. In contrast to the PessimalPrint and BaffleText CAPTCHAs (and others), no physics-based image degradations, occlusions, or extraneous patterns are employed. We report preliminary results from a human legibility trial with 57 volunteers that yielded 4275 CAPTCHA challenges and responses. ScatterType human legibility remains remarkably high even on extremely degraded cases. We speculate that this is due to Gestalt perception abilities assisted by style-specific (here, typeface-specific) consistency among primitive shape features of character fragments. Although recent efforts to automate style-consistent perceptual skills have reported progress, the best known methods do not yet pose a threat to ScatterType. The experimental data also show that subjective rating of difficulty is strongly (and usefully) correlated with illegibility. In addition, we present early insights emerging from these data as we explore the ScatterType design space -- choice of typefaces, 'words', cut positioning, and displacements -- with the goal of locating regimes in which ScatterType challenges remain comfortably legible to almost all people but strongly resist mahine-vision methods for automatic segmentation into characters.

  10. Managing burn victims of suicide bombing attacks: outcomes, lessons learnt, and changes made from three attacks in Indonesia

    PubMed Central

    Chim, Harvey; Yew, Woon Si; Song, Colin

    2007-01-01

    Introduction Terror attacks in Southeast Asia were almost nonexistent until the 2002 Bali bomb blast, considered the deadliest attack in Indonesian history. Further attacks in 2003 (Jakarta), 2004 (Jakarta), and 2005 (Bali) have turned terrorist attacks into an ever-present reality. Methods The authors reviewed medical charts of victims evacuated to the Singapore General Hospital (SGH) Burns Centre during three suicide attacks involving Bali (2002 and 2005) and the Jakarta Marriott hotel (2003). Problems faced, lessons learnt, and costs incurred are discussed. A burns disaster plan drawing on lessons learnt from these attacks is presented. Results Thirty-one patients were treated at the SGH Burns Centre in three attacks (2002 Bali attack [n = 15], 2003 Jakarta attack [n = 14], and 2005 Bali attack [n = 2]). For the 2002 Bali attack, median age was 29 years (range 20 to 50 years), median percentage of total burn surface area (TBSA) was 29% (range 5% to 55%), and median abbreviated burn severity index (ABSI) was 6 (range 3 to 10). Eight of 15 patients were admitted to the intensive care unit. For the 2003 Jakarta attack, median age was 35 years (range 24 to 56 years), median percentage of TBSA was 10% (range 2% to 46%), and median ABSI was 4 (range 3 to 9). A large number of patients had other injuries. Problems faced included manpower issues, lack of bed space, shortage of blood products, and lack of cadaver skin. Conclusion The changing nature of terror attacks mandates continued vigilance and disaster preparedness. The multidimensional burns patient, complicated by other injuries, is likely to become increasingly common. A burns disaster plan with emphasis on effective command, control, and communication as well as organisation of health care personnel following a 'team concept' will do much to ensure that the sudden onset of a crisis situation at an unexpected time does not overwhelm hospital manpower and resources. PMID:17274813

  11. Extended Password Recovery Attacks against APOP, SIP, and Digest Authentication

    NASA Astrophysics Data System (ADS)

    Sasaki, Yu; Wang, Lei; Ohta, Kazuo; Kunihiro, Noboru

    In this paper, we propose password recovery attacks against challenge-response authentication protocols. Our attacks use a message difference for a MD5 collision attack proposed in IEICE 2008. First, we show how to efficiently find a message pair that collides with the above message difference. Second, we show that a password used in authenticated post office protocol (APOP) can be recovered practically. We also show that the password recovery attack can be applied to a session initiation protocol (SIP) and digest authentication. Our attack can recover up to the first 31 password characters in a short time and up to the first 60 characters faster than the naive search method. We have implemented our attack and confirmed that 31 characters can be successfully recovered.

  12. Attack polish for nickel-base alloys and stainless steels

    DOEpatents

    Steeves, Arthur F.; Buono, Donald P.

    1983-01-01

    A chemical attack polish and polishing procedure for use on metal surfaces such as nickel base alloys and stainless steels. The chemical attack polish comprises Fe(NO.sub.3).sub.3, concentrated CH.sub.3 COOH, concentrated H.sub.2 SO.sub.4 and H.sub.2 O. The polishing procedure includes saturating a polishing cloth with the chemical attack polish and submicron abrasive particles and buffing the metal surface.

  13. Attack polish for nickel-base alloys and stainless steels

    DOEpatents

    Not Available

    1980-05-28

    A chemical attack polish and polishing procedure for use on metal surfaces such as nickel base alloys and stainless steels is described. The chemical attack polich comprises FeNO/sub 3/, concentrated CH/sub 3/COOH, concentrated H/sub 2/SO/sub 4/ and H/sub 2/O. The polishing procedure includes saturating a polishing cloth with the chemical attack polish and submicron abrasive particles and buffing the metal surface.

  14. Non-harmful insertion of data mimicking computer network attacks

    DOEpatents

    Neil, Joshua Charles; Kent, Alexander; Hash, Jr, Curtis Lee

    2016-06-21

    Non-harmful data mimicking computer network attacks may be inserted in a computer network. Anomalous real network connections may be generated between a plurality of computing systems in the network. Data mimicking an attack may also be generated. The generated data may be transmitted between the plurality of computing systems using the real network connections and measured to determine whether an attack is detected.

  15. Countermeasures for unintentional and intentional video watermarking attacks

    NASA Astrophysics Data System (ADS)

    Deguillaume, Frederic; Csurka, Gabriela; Pun, Thierry

    2000-05-01

    These last years, the rapidly growing digital multimedia market has revealed an urgent need for effective copyright protection mechanisms. Therefore, digital audio, image and video watermarking has recently become a very active area of research, as a solution to this problem. Many important issues have been pointed out, one of them being the robustness to non-intentional and intentional attacks. This paper studies some attacks and proposes countermeasures applied to videos. General attacks are lossy copying/transcoding such as MPEG compression and digital/analog (D/A) conversion, changes of frame-rate, changes of display format, and geometrical distortions. More specific attacks are sequence edition, and statistical attacks such as averaging or collusion. Averaging attack consists of averaging locally consecutive frames to cancel the watermark. This attack works well for schemes which embed random independent marks into frames. In the collusion attack the watermark is estimated from single frames (based on image denoising), and averaged over different scenes for better accuracy. The estimated watermark is then subtracted from each frame. Collusion requires that the same mark is embedded into all frames. The proposed countermeasures first ensures robustness to general attacks by spread spectrum encoding in the frequency domain and by the use of an additional template. Secondly, a Bayesian criterion, evaluating the probability of a correctly decoded watermark, is used for rejection of outliers, and to implement an algorithm against statistical attacks. The idea is to embed randomly chosen marks among a finite set of marks, into subsequences of videos which are long enough to resist averaging attacks, but short enough to avoid collusion attacks. The Bayesian criterion is needed to select the correct mark at the decoding step. Finally, the paper presents experimental results showing the robustness of the proposed method.

  16. Attribution Of Cyber Attacks On Process Control Systems

    NASA Astrophysics Data System (ADS)

    Hunker, Jeffrey; Hutchinson, Robert; Margulies, Jonathan

    The attribution of cyber attacks is an important problem. Attribution gives critical infrastructure asset owners and operators legal recourse in the event of attacks and deters potential attacks. This paper discusses attribution techniques along with the associated legal and technical challenges. It presents a proposal for a voluntary network of attributable activity, an important first step towards a more complete attribution methodology for the control systems community.

  17. Identification of cooling tower wood attack and methods of control

    SciTech Connect

    Song, P.; Trulear, M.G.

    1986-01-01

    Biological and chemical attack can greatly accelerate the deterioration of cooling tower wood. The damage, once inflicted, is irreversible and often results in premature and costly wood replacement. Biological attack is more serious than chemical, and is difficult to detect. Control of both types is essential for good tower maintenance A review of wood structures, types of attack and methods of control are presented. Effects of alkaline cooling water operation on wood deterioration are also discussed.

  18. An optical angle of attack sensor

    NASA Astrophysics Data System (ADS)

    McDevitt, T. Kevin; Owen, F. Kevin

    A major source of transonic and supersonic wind-tunnel test data uncertainty is due to angle of attack (alpha) measurement errors caused by unknown sting and balance deflections under load. A novel laser-based instrument has been developed to enable continuous time-dependent alpha measurements to be made without signal dropout. Detectors capable of 0.01-deg resolution over an 18-deg range and 0.03-deg resolution over a 44-deg range with time-dependent outputs of 60 Hz have been developed. This capability is sufficient to provide accurate real-time alpha information for correlation with model balance measurements during transport and fighter model testing. Proof-of-concept experiments, along with the results of recent measurements conducted at the NASA Ames 9 x 7-ft supersonic wind tunnel, are presented. Experiments were also conducted to determine the reliable range, sensitivity, and long-term stability of the instrument.

  19. [Cerebral infarction and transient ischemic attack].

    PubMed

    Sahara, Noriyuki; Kuwashiro, Takahiro; Okada, Yasushi

    2016-04-01

    Japanese Guidelines for the Management of Stroke 2015 was published. Here, we describe several points revised from the 2009 edition about "Cerebral infarction and transient ischemic attack (TIA)". The revision points are as follows; 1. Extension of possible time window of intravenous recombinant tissue-plasminogen activator treatment (from within 3 hours to within 4.5 hours); 2. Antiplatelet therapy in acute stage (dual antiplatelet therapy (DAPT) for non-cardioembolic ischemic stroke or TIA); 3. Endovascular recanalization therapy in acute stage; 4. Antiplatelet therapy in chronic stage (Cilostazol is recommended similar to aspirin or clopidogrel); 5. Non-vitamin K antagonist oral anticoagulants (NOACs) for non-valvular atrial fibrillation (NVAF) stroke or TIA patients; 6. Management of TIA. We explain the revised points of the guideline in the text.

  20. Capturing the uncertainty in adversary attack simulations.

    SciTech Connect

    Darby, John L.; Brooks, Traci N.; Berry, Robert Bruce

    2008-09-01

    This work provides a comprehensive uncertainty technique to evaluate uncertainty, resulting in a more realistic evaluation of PI, thereby requiring fewer resources to address scenarios and allowing resources to be used across more scenarios. For a given set of dversary resources, two types of uncertainty are associated with PI for a scenario: (1) aleatory (random) uncertainty for detection probabilities and time delays and (2) epistemic (state of knowledge) uncertainty for the adversary resources applied during an attack. Adversary esources consist of attributes (such as equipment and training) and knowledge about the security system; to date, most evaluations have assumed an adversary with very high resources, adding to the conservatism in the evaluation of PI. The aleatory uncertainty in PI is ddressed by assigning probability distributions to detection probabilities and time delays. A numerical sampling technique is used to evaluate PI, addressing the repeated variable dependence in the equation for PI.

  1. Resveratrol products resulting by free radical attack

    NASA Astrophysics Data System (ADS)

    Bader, Yvonne; Quint, R. M.; Getoff, Nikola

    2008-06-01

    Trans-resveratrol ( trans-3,4',5-trihydroxystilbene; RES), which is contained in red wine and many plants, is one of the most relevant and extensively investigated stilbenes with a broad spectrum of biological activities. Among other duties, RES has been reported to have anti-carcinogenetic activities, which could be attributed to its antioxidant properties. The degradation of RES was studied under various conditions. The products (aldehydes, carboxylic acids, etc.) generated from RES by the attack of free radicals were registered as a function of the radical concentration (absorbed radiation dose). Based on the obtained data it appears that the OH radicals are initiating the rather complicated process, which involves of the numerous consecutive reactions. A possible starting reaction mechanism is presented.

  2. European industry attacks proposed carbon tax

    SciTech Connect

    Roberts, M.

    1995-08-09

    The European chemical industry, facing growing political support for the European Commission`s latest version of the carbon dioxide (CO{sub 2})-energy tax, has renewed its attacks on the proposed law. Simon de Bree, chairman of DSM and president of the European Chemical Industry Council (Cefic; Brussels), last week wrote to Jacques Santer, president of the commission, and Solana Madariaga, current president of Europe Union`s (EU) Council of Ministers, saying the tax was {open_quotes}totally unacceptable and irresponsible in terms of EU competitiveness.{close_quotes} He says it {open_quotes}has nothing to do anymore with the protection of the environment and has instead become a normal additional taxation, disguised, for opportunistic reasons, as an environmental protection measurement.{close_quotes}

  3. Inorganic nanoparticles engineered to attack bacteria.

    PubMed

    Miller, Kristen P; Wang, Lei; Benicewicz, Brian C; Decho, Alan W

    2015-11-01

    Antibiotics were once the golden bullet to constrain infectious bacteria. However, the rapid and continuing emergence of antibiotic resistance (AR) among infectious microbial pathogens has questioned the future utility of antibiotics. This dilemma has recently fueled the marriage of the disparate fields of nanochemistry and antibiotics. Nanoparticles and other types of nanomaterials have been extensively developed for drug delivery to eukaryotic cells. However, bacteria have very different cellular architectures than eukaryotic cells. This review addresses the chemistry of nanoparticle-based antibiotic carriers, and how their technical capabilities are now being re-engineered to attack, kill, but also non-lethally manipulate the physiologies of bacteria. This review also discusses the surface functionalization of inorganic nanoparticles with small ligand molecules, polymers, and charged moieties to achieve drug loading and controllable release.

  4. Detecting Cyber Attacks On Nuclear Power Plants

    NASA Astrophysics Data System (ADS)

    Rrushi, Julian; Campbell, Roy

    This paper proposes an unconventional anomaly detection approach that provides digital instrumentation and control (I&C) systems in a nuclear power plant (NPP) with the capability to probabilistically discern between legitimate protocol frames and attack frames. The stochastic activity network (SAN) formalism is used to model the fusion of protocol activity in each digital I&C system and the operation of physical components of an NPP. SAN models are employed to analyze links between protocol frames as streams of bytes, their semantics in terms of NPP operations, control data as stored in the memory of I&C systems, the operations of I&C systems on NPP components, and NPP processes. Reward rates and impulse rewards are defined in the SAN models based on the activity-marking reward structure to estimate NPP operation profiles. These profiles are then used to probabilistically estimate the legitimacy of the semantics and payloads of protocol frames received by I&C systems.

  5. [Cerebral infarction and transient ischemic attack].

    PubMed

    Sahara, Noriyuki; Kuwashiro, Takahiro; Okada, Yasushi

    2016-04-01

    Japanese Guidelines for the Management of Stroke 2015 was published. Here, we describe several points revised from the 2009 edition about "Cerebral infarction and transient ischemic attack (TIA)". The revision points are as follows; 1. Extension of possible time window of intravenous recombinant tissue-plasminogen activator treatment (from within 3 hours to within 4.5 hours); 2. Antiplatelet therapy in acute stage (dual antiplatelet therapy (DAPT) for non-cardioembolic ischemic stroke or TIA); 3. Endovascular recanalization therapy in acute stage; 4. Antiplatelet therapy in chronic stage (Cilostazol is recommended similar to aspirin or clopidogrel); 5. Non-vitamin K antagonist oral anticoagulants (NOACs) for non-valvular atrial fibrillation (NVAF) stroke or TIA patients; 6. Management of TIA. We explain the revised points of the guideline in the text. PMID:27333757

  6. Techniques for Judging Intent Behind Network Based Cyber Attacks

    SciTech Connect

    Allen, J M

    2004-01-28

    This project developed a prototype system that can rapidly differentiate between undirected cyber attacks, and those that have a more specific and concerning intent behind them. The system responds to important cyber attacks in a tactically significant way as the attack is proceeding. It is also creates a prioritized list for the human analysts allowing them to focus on the threats mostly likely to be of interest. In the recent years the volume of attacks over the internet has increased exponentially, as they have become more and more automated. The result of this is that real threats are harder and harder to distinguish from the general threat. It is possible with our current systems to identify network packets that originated from thousands of IP addresses as probing a site like LLNL in a single day. Human analysis of these threats does not result in information that can be used for tactical response because most of the attacks are short and over before the human starts the analysis. Only a very small percentage of attacks can even be evaluated manually due to the volume. This project developed methods, and prototyped tools, that can identify attacks, slow the attack down and aid in the process of prioritizing detections. The project demonstrated that such methods exist, and that practical implementations exist for modern computers and networks. We call the tools created D.I.A.G. or Determining Internet Attackers Goals.

  7. Finite Energy and Bounded Attacks on Control System Sensor Signals

    SciTech Connect

    Djouadi, Seddik M; Melin, Alexander M; Ferragut, Erik M; Laska, Jason A

    2014-01-01

    Control system networks are increasingly being connected to enterprise level networks. These connections leave critical industrial controls systems vulnerable to cyber-attacks. Most of the effort in protecting these cyber-physical systems (CPS) has been in securing the networks using information security techniques and protection and reliability concerns at the control system level against random hardware and software failures. However, besides these failures the inability of information security techniques to protect against all intrusions means that the control system must be resilient to various signal attacks for which new analysis and detection methods need to be developed. In this paper, sensor signal attacks are analyzed for observer-based controlled systems. The threat surface for sensor signal attacks is subdivided into denial of service, finite energy, and bounded attacks. In particular, the error signals between states of attack free systems and systems subject to these attacks are quantified. Optimal sensor and actuator signal attacks for the finite and infinite horizon linear quadratic (LQ) control in terms of maximizing the corresponding cost functions are computed. The closed-loop system under optimal signal attacks are provided. Illustrative numerical examples are provided together with an application to a power network with distributed LQ controllers.

  8. Application distribution model and related security attacks in VANET

    NASA Astrophysics Data System (ADS)

    Nikaein, Navid; Kanti Datta, Soumya; Marecar, Irshad; Bonnet, Christian

    2013-03-01

    In this paper, we present a model for application distribution and related security attacks in dense vehicular ad hoc networks (VANET) and sparse VANET which forms a delay tolerant network (DTN). We study the vulnerabilities of VANET to evaluate the attack scenarios and introduce a new attacker`s model as an extension to the work done in [6]. Then a VANET model has been proposed that supports the application distribution through proxy app stores on top of mobile platforms installed in vehicles. The steps of application distribution have been studied in detail. We have identified key attacks (e.g. malware, spamming and phishing, software attack and threat to location privacy) for dense VANET and two attack scenarios for sparse VANET. It has been shown that attacks can be launched by distributing malicious applications and injecting malicious codes to On Board Unit (OBU) by exploiting OBU software security holes. Consequences of such security attacks have been described. Finally, countermeasures including the concepts of sandbox have also been presented in depth.

  9. Flight experiments with a slender cone at angle of attack

    NASA Technical Reports Server (NTRS)

    Peake, D. J.; Fisher, D. F.; Mcrae, D. S.

    1981-01-01

    The three-dimensional leeward separation about a 5 deg semi-angle cone at an 11 deg angle of attack was investigated in flight, in the wind tunnel, and by numerical computations. The test conditions were Mach numbers of 0.6, 1.5, and 1.8 at Reynolds numbers between 7 and 10 million based on free-stream conditions and a 30-inch wetted length or surface. The surface conditions measured included mean static and fluctuating pressures; skin friction magnitudes and separation line positions were obtained using obstacle blocks. The mean static pressures from flight and wind tunnel were in good agreement. The computed results gave the same distributions, but were slightly more positive in magnitude. The experimentally measured primary and secondary separation line locations compared closely with computed results. There were substantial differences in level and in trend between the surface root-mean-square pressure fluctuations obtained in flight and in the wind tunnel, due, it is thought, to a relatively high acoustic disturbance level in the tunnel compared with the quiescent conditions in flight.

  10. Passive Faraday-mirror attack in a practical two-way quantum-key-distribution system

    SciTech Connect

    Sun Shihai; Jiang Musheng; Liang Linmei

    2011-06-15

    The Faraday mirror (FM) plays a very important role in maintaining the stability of two-way plug-and-play quantum key distribution (QKD) systems. However, the practical FM is imperfect, which will not only introduce an additional quantum bit error rate (QBER) but also leave a loophole for Eve to spy the secret key. In this paper we propose a passive Faraday mirror attack in two-way QKD system based on the imperfection of FM. Our analysis shows that if the FM is imperfect, the dimension of Hilbert space spanned by the four states sent by Alice is three instead of two. Thus Eve can distinguish these states with a set of Positive Operator Valued Measure (POVM) operators belonging to three-dimension space, which will reduce the QBER induced by her attack. Furthermore, a relationship between the degree of the imperfection of FM and the transmittance of the practical QKD system is obtained. The results show that the probability that Eve loads her attack successfully depends on the degree of the imperfection of FM rapidly, but the QBER induced by Eve's attack changes slightly with the degree of the FM imperfection.

  11. Passive Faraday-mirror attack in a practical two-way quantum-key-distribution system

    NASA Astrophysics Data System (ADS)

    Sun, Shi-Hai; Jiang, Mu-Sheng; Liang, Lin-Mei

    2011-06-01

    The Faraday mirror (FM) plays a very important role in maintaining the stability of two-way plug-and-play quantum key distribution (QKD) systems. However, the practical FM is imperfect, which will not only introduce an additional quantum bit error rate (QBER) but also leave a loophole for Eve to spy the secret key. In this paper we propose a passive Faraday mirror attack in two-way QKD system based on the imperfection of FM. Our analysis shows that if the FM is imperfect, the dimension of Hilbert space spanned by the four states sent by Alice is three instead of two. Thus Eve can distinguish these states with a set of Positive Operator Valued Measure (POVM) operators belonging to three-dimension space, which will reduce the QBER induced by her attack. Furthermore, a relationship between the degree of the imperfection of FM and the transmittance of the practical QKD system is obtained. The results show that the probability that Eve loads her attack successfully depends on the degree of the imperfection of FM rapidly, but the QBER induced by Eve’s attack changes slightly with the degree of the FM imperfection.

  12. Nursing Positions

    MedlinePlus

    ... Story" 5 Things to Know About Zika & Pregnancy Nursing Positions KidsHealth > For Parents > Nursing Positions Print A ... and actually needs to feed. Getting Comfortable With Breastfeeding Nursing can be one of the most challenging ...

  13. Observations on sleeping position and essential hypertension.

    PubMed

    FitzGerald, W A

    1997-07-01

    A hypertensive black male, at risk for episodic attacks of pseudo-malignant hypertension and self-induced atrial fibrillation, seeks to discover possible clues to the pathogeneses of these strange disorders through self-study and concludes they might be associated with impaired oxygen intake, secondary to sleeping position in bed. PMID:9247903

  14. Positive Psychology

    ERIC Educational Resources Information Center

    Peterson, Christopher

    2009-01-01

    Positive psychology is a deliberate correction to the focus of psychology on problems. Positive psychology does not deny the difficulties that people may experience but does suggest that sole attention to disorder leads to an incomplete view of the human condition. Positive psychologists concern themselves with four major topics: (1) positive…

  15. Heart Attack or Sudden Cardiac Arrest: How Are They Different?

    MedlinePlus

    ... a person loses consciousness and has no pulse. Death occurs within minutes if the victim does not receive treatment. What is the link? These two distinct heart conditions are linked. Sudden cardiac arrest can occur after a heart attack, or during recovery. Heart attacks increase the risk ...

  16. The Icatibant Outcome Survey: treatment of laryngeal angioedema attacks

    PubMed Central

    Aberer, Werner; Bouillet, Laurence; Caballero, Teresa; Maurer, Marcus; Fabien, Vincent; Zanichelli, Andrea

    2016-01-01

    Objective To characterize the management and outcomes of life-threatening laryngeal attacks of hereditary angioedema (HAE) treated with icatibant in the observational Icatibant Outcome Survey (NCT01034969) registry. Methods This retrospective analysis was based on data from patients with HAE type I/II who received healthcare professional-administered or self-administered icatibant to treat laryngeal attacks between September 2008 and May 2013. Results Twenty centers in seven countries contributed data. Overall, 42 patients with HAE experienced 67 icatibant-treated laryngeal attacks. Icatibant was self-administered for 62.3% of attacks (healthcare professional-administered, 37.7%). One icatibant injection was used for 87.9% of attacks, with rescue or concomitant medication used for 9.0%. The median time to treatment was 2.0 h (n=31 attacks) and the median time to resolution was 6.0 h (n=35 attacks). Conclusions This analysis describes successful use of icatibant for the treatment of laryngeal HAE attacks in a real-world setting. PMID:27116379

  17. Sequential defense against random and intentional attacks in complex networks

    NASA Astrophysics Data System (ADS)

    Chen, Pin-Yu; Cheng, Shin-Ming

    2015-02-01

    Network robustness against attacks is one of the most fundamental researches in network science as it is closely associated with the reliability and functionality of various networking paradigms. However, despite the study on intrinsic topological vulnerabilities to node removals, little is known on the network robustness when network defense mechanisms are implemented, especially for networked engineering systems equipped with detection capabilities. In this paper, a sequential defense mechanism is first proposed in complex networks for attack inference and vulnerability assessment, where the data fusion center sequentially infers the presence of an attack based on the binary attack status reported from the nodes in the network. The network robustness is evaluated in terms of the ability to identify the attack prior to network disruption under two major attack schemes, i.e., random and intentional attacks. We provide a parametric plug-in model for performance evaluation on the proposed mechanism and validate its effectiveness and reliability via canonical complex network models and real-world large-scale network topology. The results show that the sequential defense mechanism greatly improves the network robustness and mitigates the possibility of network disruption by acquiring limited attack status information from a small subset of nodes in the network.

  18. New Attacks on Animal Researchers Provoke Anger and Worry

    ERIC Educational Resources Information Center

    Guterman, Lila

    2008-01-01

    This article reports on firebomb attacks at the homes of two animal researchers which have provoked anger and unease. The firebomb attacks, which set the home of a neuroscientist at the University of California at Santa Cruz aflame and destroyed a car parked in the driveway of another university researcher's home, have left researchers and…

  19. Israeli Adolescents' Coping Strategies in Relation to Terrorist Attacks

    ERIC Educational Resources Information Center

    Tatar, Moshe; Amram, Sima

    2007-01-01

    Exposure to terrorism seriously threatens the well-being of children and adolescents. Israeli citizens have witnessed massive ongoing terrorist attacks during the last few years. The present research, conducted among 330 Israeli adolescents, examined coping strategies in relation to terrorist attacks. We found that adolescents utilize more…

  20. Hereditary Angioedema Attacks: Local Swelling at Multiple Sites.

    PubMed

    Hofman, Zonne L M; Relan, Anurag; Hack, C Erik

    2016-02-01

    Hereditary angioedema (HAE) patients experience recurrent local swelling in various parts of the body including painful swelling of the intestine and life-threatening laryngeal oedema. Most HAE literature is about attacks located in one anatomical site, though it is mentioned that HAE attacks may also involve multiple anatomical sites simultaneously. A detailed description of such multi-location attacks is currently lacking. This study investigated the occurrence, severity and clinical course of HAE attacks with multiple anatomical locations. HAE patients included in a clinical database of recombinant human C1-inhibitor (rhC1INH) studies were evaluated. Visual analog scale scores filled out by the patients for various symptoms at various locations and investigator symptoms scores during the attack were analysed. Data of 219 eligible attacks in 119 patients was analysed. Thirty-three patients (28%) had symptoms at multiple locations in anatomically unrelated regions at the same time during their first attack. Up to five simultaneously affected locations were reported. The observation that severe HAE attacks often affect multiple sites in the body suggests that HAE symptoms result from a systemic rather than from a local process as is currently believed. PMID:25527240

  1. [Banana tree pests attacking Heliconia latispatha Benth. (Heliconiaceae)].

    PubMed

    Watanabe, Maria A

    2007-01-01

    In mid-May 2005, the caterpillars Antichloris eriphia (Fabr.) (Lepidoptera: Arctiidae) and Calligo illioneus (Cramer) (Lepidoptera: Nymphalidae) which are banana tree pests, were found attacking six-month old stalks of Heliconia latispatha Benth., planted near a banana tree plantation in Jaguariuna, SP, Brazil. The attack by C. illioneus is observed by the first time in Brazil.

  2. Detecting Distributed SQL Injection Attacks in a Eucalyptus Cloud Environment

    NASA Technical Reports Server (NTRS)

    Kebert, Alan; Barnejee, Bikramjit; Solano, Juan; Solano, Wanda

    2013-01-01

    The cloud computing environment offers malicious users the ability to spawn multiple instances of cloud nodes that are similar to virtual machines, except that they can have separate external IP addresses. In this paper we demonstrate how this ability can be exploited by an attacker to distribute his/her attack, in particular SQL injection attacks, in such a way that an intrusion detection system (IDS) could fail to identify this attack. To demonstrate this, we set up a small private cloud, established a vulnerable website in one instance, and placed an IDS within the cloud to monitor the network traffic. We found that an attacker could quite easily defeat the IDS by periodically altering its IP address. To detect such an attacker, we propose to use multi-agent plan recognition, where the multiple source IPs are considered as different agents who are mounting a collaborative attack. We show that such a formulation of this problem yields a more sophisticated approach to detecting SQL injection attacks within a cloud computing environment.

  3. Sequential defense against random and intentional attacks in complex networks.

    PubMed

    Chen, Pin-Yu; Cheng, Shin-Ming

    2015-02-01

    Network robustness against attacks is one of the most fundamental researches in network science as it is closely associated with the reliability and functionality of various networking paradigms. However, despite the study on intrinsic topological vulnerabilities to node removals, little is known on the network robustness when network defense mechanisms are implemented, especially for networked engineering systems equipped with detection capabilities. In this paper, a sequential defense mechanism is first proposed in complex networks for attack inference and vulnerability assessment, where the data fusion center sequentially infers the presence of an attack based on the binary attack status reported from the nodes in the network. The network robustness is evaluated in terms of the ability to identify the attack prior to network disruption under two major attack schemes, i.e., random and intentional attacks. We provide a parametric plug-in model for performance evaluation on the proposed mechanism and validate its effectiveness and reliability via canonical complex network models and real-world large-scale network topology. The results show that the sequential defense mechanism greatly improves the network robustness and mitigates the possibility of network disruption by acquiring limited attack status information from a small subset of nodes in the network.

  4. Pattern association--a key to recognition of shark attacks.

    PubMed

    Cirillo, G; James, H

    2004-12-01

    Investigation of a number of shark attacks in South Australian waters has lead to recognition of pattern similarities on equipment recovered from the scene of such attacks. Six cases are presented in which a common pattern of striations has been noted.

  5. Is There Anybody There? A Psychodynamic View of Panic Attack.

    ERIC Educational Resources Information Center

    Rizq, Rosemary

    2002-01-01

    Presents a process analysis of a psychodynamic intervention for a client with panic attacks. Discusses how a psychodynamic understanding of the complex etiology of the client's panic attacks that ultimately produced improved coping skills and a subjective sense of improvement for her. Process analysis is used to illustrate the theoretical base,…

  6. Examining Willingness to Attack Critical Infrastructure Online and Offline

    ERIC Educational Resources Information Center

    Holt, Thomas J.; Kilger, Max

    2012-01-01

    The continuing adoption of technologies by the general public coupled with the expanding reliance of critical infrastructures connected through the Internet has created unique opportunities for attacks by civilians and nation-states alike. Although governments are increasingly focusing on policies to deter nation-state level attacks, it is unclear…

  7. 10 CFR 52.10 - Attacks and destructive acts.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Attacks and destructive acts. 52.10 Section 52.10 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS General Provisions § 52.10 Attacks and destructive acts. Neither an applicant for a license to...

  8. 10 CFR 52.10 - Attacks and destructive acts.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Attacks and destructive acts. 52.10 Section 52.10 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS General Provisions § 52.10 Attacks and destructive acts. Neither an applicant for a license to...

  9. 10 CFR 52.10 - Attacks and destructive acts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Attacks and destructive acts. 52.10 Section 52.10 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS General Provisions § 52.10 Attacks and destructive acts. Neither an applicant for a license to...

  10. 10 CFR 52.10 - Attacks and destructive acts.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Attacks and destructive acts. 52.10 Section 52.10 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS General Provisions § 52.10 Attacks and destructive acts. Neither an applicant for a license to...

  11. 10 CFR 52.10 - Attacks and destructive acts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Attacks and destructive acts. 52.10 Section 52.10 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS General Provisions § 52.10 Attacks and destructive acts. Neither an applicant for a license to...

  12. Hereditary Angioedema Attacks: Local Swelling at Multiple Sites.

    PubMed

    Hofman, Zonne L M; Relan, Anurag; Hack, C Erik

    2016-02-01

    Hereditary angioedema (HAE) patients experience recurrent local swelling in various parts of the body including painful swelling of the intestine and life-threatening laryngeal oedema. Most HAE literature is about attacks located in one anatomical site, though it is mentioned that HAE attacks may also involve multiple anatomical sites simultaneously. A detailed description of such multi-location attacks is currently lacking. This study investigated the occurrence, severity and clinical course of HAE attacks with multiple anatomical locations. HAE patients included in a clinical database of recombinant human C1-inhibitor (rhC1INH) studies were evaluated. Visual analog scale scores filled out by the patients for various symptoms at various locations and investigator symptoms scores during the attack were analysed. Data of 219 eligible attacks in 119 patients was analysed. Thirty-three patients (28%) had symptoms at multiple locations in anatomically unrelated regions at the same time during their first attack. Up to five simultaneously affected locations were reported. The observation that severe HAE attacks often affect multiple sites in the body suggests that HAE symptoms result from a systemic rather than from a local process as is currently believed.

  13. Are Risk Assessments of a Terrorist Attack Coherent?

    ERIC Educational Resources Information Center

    Mandel, David R.

    2005-01-01

    Four experiments examined 3 types of violations of coherence criteria in risk assessments of a terrorist attack. First, the requirement that extensionally equivalent descriptions be assigned the same probability (i.e., additivity) was violated. Unpacking descriptions of an attack into subtypes led to an increase in assessed risk. Second,…

  14. "Dateline NBC"'s Persuasive Attack on Wal-Mart.

    ERIC Educational Resources Information Center

    Benoit, William L.; Dorries, Bruce

    1996-01-01

    Develops a typology of persuasive attack strategies. Identifies two key components of persuasive attack: responsibility and offensiveness. Describes several strategies for intensifying each of these elements. Applies this analysis to "Dateline NBC"'s allegations that Wal-Mart's "Buy American" campaign was deceptive. Concludes that "Dateline NBC'"s…

  15. Proximity-to-goal as a constraint on patterns of behaviour in attacker-defender dyads in team games.

    PubMed

    Headrick, Jonathon; Davids, Keith; Renshaw, Ian; Araújo, Duarte; Passos, Pedro; Fernandes, Orlando

    2012-01-01

    The aim of this study was to determine whether spatiotemporal interactions between footballers and the ball in 1 vs. 1 sub-phases are influenced by their proximity to the goal area. Twelve participants (age 15.3 ± 0.5 years) performed as attackers and defenders in 1 vs. 1 dyads across three field positions: (a) attacking the goal, (b) in midfield, and (c) advancing away from the goal area. In each position, the dribbler was required to move beyond an immediate defender with the ball towards the opposition goal. Interactions of attacker-defender dyads were filmed with player and ball displacement trajectories digitized using manual tracking software. One-way repeated measures analysis of variance was used to examine differences in mean defender-to-ball distance after this value had stabilized. Maximum attacker-to-ball distance was also compared as a function of proximity-to-goal. Significant differences were observed for defender-to-ball distance between locations (a) and (c) at the moment when the defender-to-ball distance had stabilized (a: 1.69 ± 0.64 m; c: 1.15 ± 0.59 m; P < 0.05). Findings indicate that proximity-to-goal influenced the performance of players, particularly when attacking or advancing away from goal areas, providing implications for training design in football. In this study, the task constraints of football revealed subtly different player interactions than observed in previous studies of dyadic systems in basketball and rugby union.

  16. Positional plagiocephaly

    PubMed Central

    Cummings, Carl

    2011-01-01

    Cranial asymmetry occurring as a result of forces that deform skull shape in the supine position is known as deformational plagiocephaly. The risk of plagiocephaly may be modified by positioning the baby on alternate days with the head to the right or the left side, and by increasing time spent in the prone position during awake periods. When deformational plagiocephaly is already present, physiotherapy (including positioning equivalent to the preventive positioning, and exercises as needed for torticollis and positional preference) has been shown to be superior to counselling about preventive positioning only. Helmet therapy (moulding therapy) to reduce skull asymmetry has some drawbacks: it is expensive, significantly inconvenient due to the long hours of use per day and associated with skin complications. There is evidence that helmet therapy may increase the initial rate of improvement of asymmetry, but there is no evidence that it improves the final outcome for patients with moderate or severe plagiocephaly. PMID:23024590

  17. Expected losses, insurability, and benefits from reducing vulnerability to attacks.

    SciTech Connect

    Nozick, Linda Karen; Carlson, Rolf Erik; Turnquist, Mark Alan

    2004-03-01

    A model of malicious attacks against an infrastructure system is developed that uses a network representation of the system structure together with a Hidden Markov Model of an attack at a node of that system and a Markov Decision Process model of attacker strategy across the system as a whole. We use information systems as an illustration, but the analytic structure developed can also apply to attacks against physical facilities or other systems that provide services to customers. This structure provides an explicit mechanism to evaluate expected losses from malicious attacks, and to evaluate changes in those losses that would result from system hardening. Thus, we provide a basis for evaluating the benefits of system hardening. The model also allows investigation of the potential for the purchase of an insurance contract to cover the potential losses when safeguards are breached and the system fails.

  18. Optimal attack strategy of complex networks based on tabu search

    NASA Astrophysics Data System (ADS)

    Deng, Ye; Wu, Jun; Tan, Yue-jin

    2016-01-01

    The problem of network disintegration has broad applications and recently has received growing attention, such as network confrontation and disintegration of harmful networks. This paper presents an optimized attack strategy model for complex networks and introduces the tabu search into the network disintegration problem to identify the optimal attack strategy, which is a heuristic optimization algorithm and rarely applied to the study of network robustness. The efficiency of the proposed solution was verified by comparing it with other attack strategies used in various model networks and real-world network. Numerical experiments suggest that our solution can improve the effect of network disintegration and that the "best" choice for node failure attacks can be identified through global searches. Our understanding of the optimal attack strategy may also shed light on a new property of the nodes within network disintegration and deserves additional study.

  19. Simulated predator attacks on flocks: a comparison of tactics.

    PubMed

    Demšar, Jure; Lebar Bajec, Iztok

    2014-01-01

    It is not exactly known why birds aggregate in coordinated flocks. The most common hypothesis proposes that the reason is protection from predators. Most of the currently developed examples of individual-based predator-prey models assume predators are attracted to the center of a highly coordinated flock. This proposed attraction of a predator to a flock would appear to be contradictory to an alternate hypothesis that flocks evolved as a protection against predation. In an attempt to resolve this apparent conflict, in this article we use a fuzzy individual-based model to study three attack tactics (attack center, attack nearest, attack isolated) and analyze the success of predation on two types of prey (social and individualistic). Our simulations revealed that social flocking (as opposed to individualistic behavior) is the optimal anti-predatory response to predators attacking mainly isolated individuals. PMID:24730766

  20. IVs to Skip for Immunizing WEP against FMS Attack

    NASA Astrophysics Data System (ADS)

    Kobara, Kazukuni; Imai, Hideki

    The WEP (Wired Equivalent Privacy) is a part of IEEE 802.11 standard designed for protecting over-the-air communication. While almost all of the WLAN (Wireless LAN) cards and the APs (Access Points) support WEP, a serious key recovery attack (aka FMS attack) was identified by Fluhrer et al. The FMS attack can basically be prevented by skipping IVs (Initial Values) used in the attack, but naive skip methods reveal information on the WEP key since most of them depend on the WEP key and the patterns of the skipped IV reveal it. In order to skip IVs safely, the skip patterns must be chosen carefully. In this paper, we review the attack conditions (6) and (7), whose success probability is the highest, 0.05, amongst all known conditions to guess one key-byte from one packet. Then we identify their safe skip patterns.

  1. Step to improve neural cryptography against flipping attacks.

    PubMed

    Zhou, Jiantao; Xu, Qinzhen; Pei, Wenjiang; He, Zhenya; Szu, Harold

    2004-12-01

    Synchronization of neural networks by mutual learning has been demonstrated to be possible for constructing key exchange protocol over public channel. However, the neural cryptography schemes presented so far are not the securest under regular flipping attack (RFA) and are completely insecure under majority flipping attack (MFA). We propose a scheme by splitting the mutual information and the training process to improve the security of neural cryptosystem against flipping attacks. Both analytical and simulation results show that the success probability of RFA on the proposed scheme can be decreased to the level of brute force attack (BFA) and the success probability of MFA still decays exponentially with the weights' level L. The synchronization time of the parties also remains polynomial with L. Moreover, we analyze the security under an advanced flipping attack.

  2. Attacks on Bluetooth Security Architecture and Its Countermeasures

    NASA Astrophysics Data System (ADS)

    Iqbal, Mian Muhammad Waseem; Kausar, Firdous; Wahla, Muhammad Arif

    WPANs compliment the traditional IEEE 802.11 wireless networks by facilitating the clients with flexibility in network topologies, higher mobility and relaxed configuration/hardware requirements. Bluetooth, a WPAN technology, is an open standard for short-range radio frequency (RF) communication. However, it is also susceptible to typical security threats found in wireless LANs. This paper discuses some of the attack scenarios against the bluetooth network such as hostile intrusion, active Man-in-the-Middle (MITM) attack using unit key and various forms of denial of service (DoS) attacks. These threats and attacks compromise the confidentiality and availability of bluetooth data and services. This paper proposes an improved security architecture for bluetooth device which provides protection against the above mentioned attacks.

  3. Weak laws against acid attacks on women: an Indian perspective.

    PubMed

    Ahmad, Nehaluddin

    2012-01-01

    Acid attacks, especially on women, have seen an alarming growth in India over the last decade. While these attacks can be attributed to various factors such as the social weakness of women in a male-dominated society, the situation is exacerbated by the general neglect of the lawmakers. As acid is inexpensive and easily available, it serves as an ideal weapon for the perpetrators. Further, as this offence is bailable in certain situations, the punishment does not act as a sufficient deterrent in most cases. This paper describes the horrendous effects that acid attacks have on the victims physically, psychologically and socially. It also examines the contemporary laws governing acid attacks on victims and offenders. Ideas for a better legal approach will also be examined with special reference to acid attacks as a crime, and the validity of specific legal provisions for female victims.

  4. Metrics for Assessment of Smart Grid Data Integrity Attacks

    SciTech Connect

    Annarita Giani; Miles McQueen; Russell Bent; Kameshwar Poolla; Mark Hinrichs

    2012-07-01

    There is an emerging consensus that the nation’s electricity grid is vulnerable to cyber attacks. This vulnerability arises from the increasing reliance on using remote measurements, transmitting them over legacy data networks to system operators who make critical decisions based on available data. Data integrity attacks are a class of cyber attacks that involve a compromise of information that is processed by the grid operator. This information can include meter readings of injected power at remote generators, power flows on transmission lines, and relay states. These data integrity attacks have consequences only when the system operator responds to compromised data by redispatching generation under normal or contingency protocols. These consequences include (a) financial losses from sub-optimal economic dispatch to service loads, (b) robustness/resiliency losses from placing the grid at operating points that are at greater risk from contingencies, and (c) systemic losses resulting from cascading failures induced by poor operational choices. This paper is focused on understanding the connections between grid operational procedures and cyber attacks. We first offer two examples to illustrate how data integrity attacks can cause economic and physical damage by misleading operators into taking inappropriate decisions. We then focus on unobservable data integrity attacks involving power meter data. These are coordinated attacks where the compromised data are consistent with the physics of power flow, and are therefore passed by any bad data detection algorithm. We develop metrics to assess the economic impact of these attacks under re-dispatch decisions using optimal power flow methods. These metrics can be use to prioritize the adoption of appropriate countermeasures including PMU placement, encryption, hardware upgrades, and advance attack detection algorithms.

  5. Neurons under viral attack: victims or warriors?

    PubMed

    Chakraborty, Swarupa; Nazmi, Arshed; Dutta, Kallol; Basu, Anirban

    2010-01-01

    When the central nervous system (CNS) is under viral attack, defensive antiviral responses must necessarily arise from the CNS itself to rapidly and efficiently curb infections with minimal collateral damage to the sensitive, specialized and non-regenerating neural tissue. This presents a unique challenge because an intact blood-brain barrier (BBB) and lack of proper lymphatic drainage keeps the CNS virtually outside the radar of circulating immune cells that are at constant vigilance for antigens in peripheral tissues. Limited antigen presentation skills of CNS cells in comparison to peripheral tissues is because of a total lack of dendritic cells and feeble expression of major histocompatibility complex (MHC) proteins in neurons and glia. However, research over the past two decades has identified immune effector mechanisms intrinsic to the CNS for immediate tackling, attenuating and clearing of viral infections, with assistance pouring in from peripheral circulation in the form of neutralizing antibodies and cytotoxic T cells at a later stage. Specialized CNS cells, microglia and astrocytes, were regarded as sole sentinels of the brain for containing a viral onslaught but neurons held little recognition as a potential candidate for protecting itself from the proliferation and pathogenesis of neurotropic viruses. Accumulating evidence however indicates that extracellular insult causes neurons to express immune factors characteristic of lymphoid tissues. This article aims to comprehensively analyze current research on this conditional alteration in the protein expression repertoire of neurons and the role it plays in CNS innate immune response to counter viral infections.

  6. Prodromes and predictors of migraine attack.

    PubMed

    Rossi, Paolo; Ambrosini, Anna; Buzzi, M Gabriella

    2005-01-01

    Premonitory symptoms of migraine include a wide and heterogeneous collection of cognitive, psychic and physical changes preceding and forewarning of an attack by a few hours to 2-3 days. To date, premonitory symptoms have received little attention in the literature, being treated more as a curiosity than as a primary feature of migraine. This paper provides an extensive critical review of this neglected area of migraine research in the light of the recent advances in our understanding of the pathogenetic mechanisms of migraine. Epidemiological and clinical studies that have investigated the premonitory symptoms of migraine lack scientific rigour, producing conflicting results, whilst genetic and pathophysiological investigations are still in their very early stages. There is evidence supporting the idea that premonitory symptoms could be used as a phenotypical marker to identify subgroups of migraineurs which could show correlations with specific clinical expressions of the disease, genotypes, or responses to treatments. Future studies are needed to clarify the clinical, pathophysiological and therapeutic significance of premonitory symptoms. PMID:16483459

  7. Node Survival in Networks under Correlated Attacks.

    PubMed

    Hao, Yan; Armbruster, Dieter; Hütt, Marc-Thorsten

    2015-01-01

    We study the interplay between correlations, dynamics, and networks for repeated attacks on a socio-economic network. As a model system we consider an insurance scheme against disasters that randomly hit nodes, where a node in need receives support from its network neighbors. The model is motivated by gift giving among the Maasai called Osotua. Survival of nodes under different disaster scenarios (uncorrelated, spatially, temporally and spatio-temporally correlated) and for different network architectures are studied with agent-based numerical simulations. We find that the survival rate of a node depends dramatically on the type of correlation of the disasters: Spatially and spatio-temporally correlated disasters increase the survival rate; purely temporally correlated disasters decrease it. The type of correlation also leads to strong inequality among the surviving nodes. We introduce the concept of disaster masking to explain some of the results of our simulations. We also analyze the subsets of the networks that were activated to provide support after fifty years of random disasters. They show qualitative differences for the different disaster scenarios measured by path length, degree, clustering coefficient, and number of cycles.

  8. Helicobacter pylori defense against oxidative attack.

    PubMed

    Stent, Andrew; Every, Alison L; Sutton, Philip

    2012-03-15

    Helicobacter pylori is a microaerophilic, gram-negative pathogen of the human stomach. Despite the chronic active gastritis that develops following colonization, H. pylori is able to persist unharmed in the stomach for decades. Much of the damage caused by gastric inflammation results from the accumulation of reactive oxygen/nitrogen species within the stomach environment, which can induce oxidative damage in a wide range of biological molecules. Without appropriate defenses, this oxidative damage would be able to rapidly kill nearby H. pylori, but the organism employs a range of measures, including antioxidant enzymes, biological repair systems, and inhibitors of oxidant generation, to counter the attack. Despite the variety of measures employed to defend against oxidative injury, these processes are intimately interdependent, and any deficiency within the antioxidant system is generally sufficient to cause substantial impairment of H. pylori viability and persistence. This review provides an overview of the development of oxidative stress during H. pylori gastritis and examines the methods the organism uses to survive the resultant damage.

  9. Node Survival in Networks under Correlated Attacks

    PubMed Central

    Hao, Yan; Armbruster, Dieter; Hütt, Marc-Thorsten

    2015-01-01

    We study the interplay between correlations, dynamics, and networks for repeated attacks on a socio-economic network. As a model system we consider an insurance scheme against disasters that randomly hit nodes, where a node in need receives support from its network neighbors. The model is motivated by gift giving among the Maasai called Osotua. Survival of nodes under different disaster scenarios (uncorrelated, spatially, temporally and spatio-temporally correlated) and for different network architectures are studied with agent-based numerical simulations. We find that the survival rate of a node depends dramatically on the type of correlation of the disasters: Spatially and spatio-temporally correlated disasters increase the survival rate; purely temporally correlated disasters decrease it. The type of correlation also leads to strong inequality among the surviving nodes. We introduce the concept of disaster masking to explain some of the results of our simulations. We also analyze the subsets of the networks that were activated to provide support after fifty years of random disasters. They show qualitative differences for the different disaster scenarios measured by path length, degree, clustering coefficient, and number of cycles. PMID:25932635

  10. Pirate attacks affect Indian Ocean climate research

    NASA Astrophysics Data System (ADS)

    Smith, Shawn R.; Bourassa, Mark A.; Long, Michael

    2011-07-01

    Pirate attacks in the Gulf of Aden and the Indian Ocean off the coast of Somalia nearly doubled from 111 in 2008 to 217 in 2009 [International Maritime Bureau, 2009, International Maritime Bureau, 2010]. Consequently, merchant vessel traffic in the area around Somalia significantly decreased. Many of these merchant vessels carry instruments that record wind and other weather conditions near the ocean surface, and alterations in ship tracks have resulted in a hole sized at about 2.5 million square kilometers in the marine weather-observing network off the coast of Somalia. The data void exists in the formation region of the Somali low-level jet, a wind pattern that is one of the main drivers of the Indian summer monsoon. Further, a stable, multidecadal record has been interrupted, and consequently, long-term analyses of the jet derived from surface wind data are now showing artificial anomalies that will affect efforts by scientists to identify interannual to decadal variations in the climate of the northwestern Indian Ocean.

  11. Pre-Attack Symptomatology and Temperament as Predictors of Children's Responses to the September 11 Terrorist Attacks

    ERIC Educational Resources Information Center

    Lengua, Liliana J.; Long, Anna C.; Smith, Kimberlee I.; Meltzoff, Andrew N.

    2005-01-01

    Background: The aims of this study were to assess the psychological response of children following the September 11, 2001 terrorist attacks in New York and Washington, DC and to examine prospective predictors of children's post-attack responses. Method: Children's responses were assessed in a community sample of children in Seattle, Washington,…

  12. Trim angle of attack of flexible wings using non-linear aerodynamics

    NASA Astrophysics Data System (ADS)

    Cohen, David Erik

    Multidisciplinary interactions are expected to play a significant role in the design of future high-performance aircraft (Blended-Wing Body, Truss-Braced wing; High Speed Civil transport, High-Altitude Long Endurance aircraft and future military aircraft). Also, the availability of supercomputers has made it now possible to employ high-fidelity models (Computational Fluid Dynamics for fluids and detailed finite element models for structures) at the preliminary design stage. A necessary step at that stage is to calculate the wing angle-of-attack at which the wing will generate the desired lift for the specific flight maneuver. Determination of this angle, a simple affair when the wing is rigid and the flow regime linear, becomes difficult when the wing is flexible and the flow regime non-linear. To solve this inherently nonlinear problem, a Newton's method type algorithm is developed to simultaneously calculate the deflection and the angle of attack. The developed algorithm is tested for a wing, used for in-house aeroelasticity research at Boeing (previously McDonnell Douglas) Long Beach. The trim angle of attack is calculated for a range of desired lift values. In addition to the Newton's method algorithm, a non derivative method (NDM) based on fixed point iteration, typical of fixed angle of attack calculations in aeroelasticity, is employed. The NDM, which has been extended to be able to calculate trim angle of attack, is used for one of the cases. The Newton's method calculation converges in fewer iterations, but requires more CPU time than the NDM method. The NDM, however, results in a slightly different value of the trim angle of attack. It should be noted that NDM will converge in a larger number of iterations as the dynamic pressure increases. For one value of the desired lift, both viscous and inviscid results were generated. The use of the inviscid flow model while not resulting in a markedly different value for the trim angle of attack, does result in a

  13. Satellite positioning

    NASA Technical Reports Server (NTRS)

    Colombo, Oscar L.; Watkins, Michael M.

    1991-01-01

    Developments in satellite positioning techniques and their applications are reviewed on the basis of the theoretical and practical work published by U.S. researchers in 1987-1990. Current techniques are classified into two main categories: satellite laser tracking and radio tracking. Particular attention is given to the Geoscience Laser Ranging System, the Lunar Laser Ranging concept; GPS ephemerides determination, fiducial networks, and reference frame; static GPS positioning; and kinematic GPS positioning.

  14. LG-ANALYST: linguistic geometry for master air attack planning

    NASA Astrophysics Data System (ADS)

    Stilman, Boris; Yakhnis, Vladimir; Umanskiy, Oleg

    2003-09-01

    We investigate the technical feasibility of implementing LG-ANALYST, a new software tool based on the Linguistic Geometry (LG) approach. The tool will be capable of modeling and providing solutions to Air Force related battlefield problems and of conducting multiple experiments to verify the quality of the solutions it generates. LG-ANALYST will support generation of the Fast Master Air Attack Plan (MAAP) with subsequent conversion into Air Tasking Order (ATO). An Air Force mission is modeled employing abstract board games (ABG). Such a mission may include, for example, an aircraft strike package moving to a target area with the opposing side having ground-to-air missiles, anti-aircraft batteries, fighter wings, and radars. The corresponding abstract board captures 3D air space, terrain, the aircraft trajectories, positions of the batteries, strategic features of the terrain, such as bridges, and their status, radars and illuminated space, etc. Various animated views are provided by LG-ANALYST including a 3D view for realistic representation of the battlespace and a 2D view for ease of analysis and control. LG-ANALYST will allow a user to model full scale intelligent enemy, plan in advance, re-plan and control in real time Blue and Red forces by generating optimal (or near-optimal) strategies for all sides of a conflict.

  15. Presentation attack detection for face recognition using light field camera.

    PubMed

    Raghavendra, R; Raja, Kiran B; Busch, Christoph

    2015-03-01

    The vulnerability of face recognition systems isa growing concern that has drawn the interest from both academic and research communities. Despite the availability of a broad range of face presentation attack detection (PAD)(or countermeasure or antispoofing) schemes, there exists no superior PAD technique due to evolution of sophisticated presentation attacks (or spoof attacks). In this paper, we present a new perspective for face presentation attack detection by introducing light field camera (LFC). Since the use of a LFC can record the direction of each incoming ray in addition to the intensity, it exhibits an unique characteristic of rendering multiple depth(or focus) images in a single capture. Thus, we present a novel approach that involves exploring the variation of the focus between multiple depth (or focus) images rendered by the LFC that in turn can be used to reveal the presentation attacks. To this extent, we first collect a new face artefact database using LFC that comprises of 80 subjects. Face artefacts are generated by simulating two widely used attacks, such as photo print and electronic screen attack. Extensive experiments carried out on the light field face artefact database have revealed the outstanding performance of the proposed PAD scheme when benchmarked with various well established state-of-the-art schemes. PMID:25622320

  16. Falsification Attacks against WPA-TKIP in a Realistic Environment

    NASA Astrophysics Data System (ADS)

    Todo, Yosuke; Ozawa, Yuki; Ohigashi, Toshihiro; Morii, Masakatu

    In this paper, we propose two new falsification attacks against Wi-Fi Protected Access Temporal Key Integrity Protocol (WPA-TKIP). A previous realistic attack succeeds only for a network that supports IEEE 802.11e QoS features by both an access point (AP) and a client, and it has an execution time of 12-15min, in which it recovers a message integrity code (MIC) key from an ARP packet. Our first attack reduces the execution time for recovering a MIC key. It can recover the MIC key within 7-8min. Our second attack expands its targets that can be attacked. This attack focuses on a new vulnerability of QoS packet processing, and this vulnerability can remove the condition that the AP supports IEEE 802.11e. In addition, we discovered another vulnerability by which our attack succeeds under the condition that the chipset of the client supports IEEE 802.11e even if the client disables this standard through the OS. We demonstrate that chipsets developed by several kinds of vendors have the same vulnerability.

  17. Optimal response to attacks on the open science grids.

    SciTech Connect

    Altunay, M.; Leyffer, S.; Linderoth, J. T.; Xie, Z.

    2011-01-01

    Cybersecurity is a growing concern, especially in open grids, where attack propagation is easy because of prevalent collaborations among thousands of users and hundreds of institutions. The collaboration rules that typically govern large science experiments as well as social networks of scientists span across the institutional security boundaries. A common concern is that the increased openness may allow malicious attackers to spread more readily around the grid. We consider how to optimally respond to attacks in open grid environments. To show how and why attacks spread more readily around the grid, we first discuss how collaborations manifest themselves in the grids and form the collaboration network graph, and how this collaboration network graph affects the security threat levels of grid participants. We present two mixed-integer program (MIP) models to find the optimal response to attacks in open grid environments, and also calculate the threat level associated with each grid participant. Given an attack scenario, our optimal response model aims to minimize the threat levels at unaffected participants while maximizing the uninterrupted scientific production (continuing collaborations). By adopting some of the collaboration rules (e.g., suspending a collaboration or shutting down a site), the model finds optimal response to subvert an attack scenario.

  18. Risk factors for hypertensive attack during pheochromocytoma resection

    PubMed Central

    Kwon, Se Yun; Lee, Kyung Seop; Lee, Jun Nyung; Ha, Yun-Sok; Choi, Seock Hwan; Kim, Hyun Tae; Kim, Tae-Hwan; Yoo, Eun Sang

    2016-01-01

    Purpose We aimed to retrospectively evaluate the risk factors for hypertensive attack during adrenalectomy in patients with pheochromocytoma. Despite the development of newer surgical and anesthetic techniques for the management of pheochromocytoma, intraoperative hypertensive attack continues to present a challenge. Materials and Methods Data from 53 patients diagnosed with pheochromocytoma at Kyungpook National Uriversity Medical Center between January 2000 and June 2012 were retrospectively analyzed. The subjects were divided into 2 groups depending on the presence or absence of hypertensive attack at the time of surgery. Patient demographic characteristics and preoperative evaluations were assessed for their prognostic relevance with respect to hypertensive attack. A univariate analysis was conducted, and a multivariate logistic regression analysis was also performed. Results In the univariate analysis, systolic blood pressure at presentation, preoperative hormonal status (including epinephrine, norepinephrine, vanillylmandelic acid, and metanephrine levels in a 24-hour urine sample), tumor size, and postoperative systolic blood pressure were significantly associated with the development of hypertensive attack. In the multivariate analysis, preoperative epinephrine level and tumor size were independent factors that predicted hypertensive attack. The highest odds ratio for tumor size (2.169) was obtained at a cutoff value of 4.25 cm and the highest odds ratio for preoperative epinephrine (1.020) was obtained at a cutoff value of 166.3 µg/d. Conclusions In this study, a large tumor size and an elevated preoperative urinary epinephrine level were risk factors for intraoperative hypertensive attack in patients with pheochromocytoma. PMID:27194549

  19. Positive Psychotherapy

    ERIC Educational Resources Information Center

    Seligman, Martin E. P.; Rashid, Tayyab; Parks, Acacia C.

    2006-01-01

    Positive psychotherapy (PPT) contrasts with standard interventions for depression by increasing positive emotion, engagement, and meaning rather than directly targeting depressive symptoms. The authors have tested the effects of these interventions in a variety of settings. In informal student and clinical settings, people not uncommonly reported…

  20. A General Ligand Design for Gold Catalysis allowing Ligand-Directed Anti Nucleophilic Attack of Alkynes

    PubMed Central

    Wang, Yanzhao; Wang, Zhixun; Li, Yuxue; Wu, Gongde; Cao, Zheng; Zhang, Liming

    2014-01-01

    Most homogenous gold catalyses demand ≥0.5 mol % catalyst loading. Due to the high cost of gold, these reactions are unlikely to be applicable in medium or large scale applications. Here we disclose a novel ligand design based on the privileged biphenyl-2-phosphine framework that offers a potentially general approach to dramatically lowering catalyst loading. In this design, an amide group at the 3’ position of the ligand framework directs and promotes nucleophilic attack at the ligand gold complex-activated alkyne, which is unprecedented in homogeneous gold catalysis considering the spatial challenge of using ligand to reach antiapproaching nucleophile in a linear P-Au-alkyne centroid structure. With such a ligand, the gold(I) complex becomes highly efficient in catalyzing acid addition to alkynes, with a turnover number up to 99,000. Density functional theory calculations support the role of the amide moiety in directing the attack of carboxylic acid via hydrogen bonding. PMID:24704803

  1. Positioning Agility

    NASA Astrophysics Data System (ADS)

    Oza, Nilay; Abrahamsson, Pekka; Conboy, Kieran

    Agile methods are increasingly adopted by European companies. Academics too are conducting numerous studies on different tenets of agile methods. Companies often feel proud in marketing themselves as ‘agile’. However, the true notion of ‘being agile’ seems to have been overlooked due to lack of positioning of oneself for agility. This raises a call for more research and interactions between academia and the industry. The proposed workshop refers to this call. It will be highly relevant to participants, interested in positioning their company’s agility from organizational, group or project perspectives. The positioning of agility will help companies to better align their agile practices with stakeholder values. Results of the workshop will be shared across participants and they will also have opportunity to continue their work on agile positioning in their companies. At broader level, the work done in this workshop will contribute towards developing Agile Positioning System.

  2. Transient ischemic attack as a medical emergency.

    PubMed

    Okada, Yasushi

    2014-01-01

    Since transient ischemic attack (TIA) is regarded as a medical emergency with high risk for early stroke recurrence, the underlying mechanisms should be immediately clarified to conclude a definitive diagnosis and provide early treatment. Early risk stratification using ABCD(2) scores can predict the risk of ischemic stroke occurring after TIA. Carotid ultrasonography (US) can evaluate the degree of stenosis, plaque properties and flow velocity of ICA lesions. High-risk mobile plaques can be classified by carotid US, and aortogenic sources of emboli can be detected by transesophageal echocardiography. Cardiac monitoring and blood findings are thought to play a key role in a diagnosis of cardioembolic TIA. Diffusion-weighted imaging (DWI)-MRI and MR angiography are also indispensable to understand the mechanism of TIA and cerebral circulation. To prevent subsequent stroke arising from TIA, antiplatelet and anticoagulant therapies should be started immediately along with comprehensive management of life-style, hypertension, diabetes mellitus, dyslipidemia and other atherosclerotic diseases. Carotid endarterectomy and endovascular intervention are critical for treating symptomatic patients with significant stenosis of ICA. A novel concept of acute cerebrovascular syndrome (ACVS) has recently been advocated to increase awareness of TIA among citizens, patients and medical professionals. TIA should be recognized as the last opportunity to avoid irreversible ischemic stroke and its sequelae. The clinical relevance of the new concept of ACVS is advocated by early recurrence after TIA, analysis of high-risk TIA, treatment strategies and the optimal management of TIA. Raising TIA awareness should also proceed across many population sectors. PMID:24157554

  3. TCPL: A Defense against wormhole attacks in wireless sensor networks

    NASA Astrophysics Data System (ADS)

    Kumar, K. E. Naresh; Waheed, Mohd. Abdul; Basappa, K. Kari

    2010-10-01

    Do In this paper presents recent advances in technology have made low-cost, low-power wireless sensors with efficient energy consumption. A network of such nodes can coordinate among themselves for distributed sensing and processing of certain data. For which, we propose an architecture to provide a stateless solution in sensor networks for efficient routing in wireless sensor networks. This type of architecture is known as Tree Cast. We propose a unique method of address allocation, building up multiple disjoint trees which are geographically inter-twined and rooted at the data sink. Using these trees, routing messages to and from the sink node without maintaining any routing state in the sensor nodes is possible. In this paper, we introduce the wormhole attack, a severe attack in ad hoc networks that is particularly challenging to defend against. The wormhole attack is possible even if the attacker has not compromised any hosts and even if all communication provides authenticity and confidentiality. In the wormhole attack, an attacker records packets (or bits) at one location in the network, tunnels them to another location, and retransmits them there into the network. The wormhole attack can form a serious threat in wireless networks, especially against many sensor network routing protocols and location-based wireless security systems. For example, most existing ad hoc network routing protocols, without some mechanism to defend against the wormhole attack, would be unable to find routes longer than one or two hops, severely disrupting communication. We present a new, general mechanism, called packet leashes, for detecting and thus defending against wormhole attacks, and we present a specific protocol, called TIK, that implements leashes.

  4. Cherry Consumption and the Risk of Recurrent Gout Attacks

    PubMed Central

    Zhang, Yuqing; Neogi, Tuhina; Chen, Clara; Chaisson, Christine; Hunter, David; Choi, Hyon K.

    2012-01-01

    Objective To study the relation between cherry intake and the risk of recurrent gout attacks among individuals with gout. Methods We conducted a case-crossover study to examine associations of a set of putative risk factors with recurrent gout attacks. Individuals with gout were prospectively recruited and followed online for one year. Participants were asked about the following information when experiencing a gout attack: the onset date of the gout attack, symptoms and signs, medications (including anti-gout medications), and potential risk factors (including daily intake of cherries and cherry extract) during the 2-day period prior to the gout attack. We assessed the same exposure information over 2-day control periods. We estimated the risk of recurrent gout attacks related to cherry intake using conditional logistic regression. Results Our study included 633 individuals with gout. Cherry intake over a 2-day period was associated with a 35% lower risk of gout attacks compared with no intake (multivariate odds ratio [OR] = 0.65, 95% CI: 0.50-0.85). Cherry extract intake showed a similar inverse association (multivariate OR=0.55, 95% CI: 0.30-0.98). The effect of cherry intake persisted across subgroups by sex, obesity status, purine intake, alcohol use, diuretic use, and use of anti-gout medications. When cherry intake was combined with allopurinol use, the risk of gout attacks was 75% lower than periods without either exposure (OR=0.25, 95% CI: 0.15-0.42). Conclusions These findings suggest that cherry intake is associated with a lower risk of gout attacks. PMID:23023818

  5. TCPL: A Defense against wormhole attacks in wireless sensor networks

    SciTech Connect

    Kumar, K. E. Naresh; Waheed, Mohd. Abdul; Basappa, K. Kari

    2010-10-26

    Do In this paper presents recent advances in technology have made low-cost, low-power wireless sensors with efficient energy consumption. A network of such nodes can coordinate among themselves for distributed sensing and processing of certain data. For which, we propose an architecture to provide a stateless solution in sensor networks for efficient routing in wireless sensor networks. This type of architecture is known as Tree Cast. We propose a unique method of address allocation, building up multiple disjoint trees which are geographically inter-twined and rooted at the data sink. Using these trees, routing messages to and from the sink node without maintaining any routing state in the sensor nodes is possible. In this paper, we introduce the wormhole attack, a severe attack in ad hoc networks that is particularly challenging to defend against. The wormhole attack is possible even if the attacker has not compromised any hosts and even if all communication provides authenticity and confidentiality. In the wormhole attack, an attacker records packets (or bits) at one location in the network, tunnels them to another location, and retransmits them there into the network. The wormhole attack can form a serious threat in wireless networks, especially against many sensor network routing protocols and location-based wireless security systems. For example, most existing ad hoc network routing protocols, without some mechanism to defend against the wormhole attack, would be unable to find routes longer than one or two hops, severely disrupting communication. We present a new, general mechanism, called packet leashes, for detecting and thus defending against wormhole attacks, and we present a specific protocol, called TIK, that implements leashes.

  6. Smoking Behavior and Alcohol Consumption in Individuals With Panic Attacks

    PubMed Central

    Mathew, Amanda R.; Norton, Peter J.; Zvolensky, Michael J.; Buckner, Julia D.; Smits, Jasper A. J.

    2011-01-01

    Individuals with anxiety often report greater smoking and drinking behaviors relative to those without a history of anxiety. In particular, smoking and alcohol use have been directly implicated among individuals experiencing panic attacks, diagnosed with panic disorder, or high on panic-relevant risk factors such as anxiety sensitivity. Less is known, however, about specific features of panic that may differentiate among those who do or do not use cigarettes or alcohol. The purpose of the current study was to replicate previous research findings of an association between panic symptomatology, cigarette smoking, and alcohol consumption, as well as extend findings by examining whether specific symptoms of panic attacks differentiated among those who do or do not use cigarettes or alcohol. Participants (n = 489) completed the Panic Attack Questionnaire-IV, a highly detailed assessment of panic attacks and symptoms, as well as self-report measures of smoking history and alcohol use. Consistent with previous research, participants who reported a history of panic attacks (n = 107) were significantly more likely to report current daily or lifetime daily cigarette smoking, and significantly greater hazardous or harmful alcohol use than participants with no panic history (n = 382). Although smoking and hazardous alcohol use were highly associated regardless of panic status, participants with panic attacks showed elevated hazardous alcohol use after controlling for daily or lifetime smoking. Surprisingly, although participants who reported having had at least one panic attack were more likely to smoke, panic attack symptoms, intensity, or frequency did not differentiate panickers who did or did not smoke. Furthermore, panic-related variables were not shown to differentially relate to problematic drinking among panickers. Implications for understanding the complex relationship between panic attacks and smoking and drinking behaviors are discussed. PMID:21915160

  7. Exploring Windows Domain-Level Defenses Against Authentication Attacks

    SciTech Connect

    Nichols, Jeff A. {Cyber Sciences}; Curtis, Laura

    2016-01-01

    We investigated the security resilience of the current Windows Active Directory (AD) environments to Pass-the-Hash and Pass- the-Ticket credential theft attacks. While doing this, we discovered a way to trigger the removal of all previously issued authentication credentials for a client, thus preventing their use by attackers. After triggered, the user is forced to contact the domain administrators and to authenticate to the AD to continue. This could become the basis for a response that arrests the spread of a detected attack. Operating in a virtualized XenServer environment, we were able to carefully determine and recreate the conditions necessary to cause this response.

  8. Towards A Taxonomy Of Attacks Against Energy Control Systems

    NASA Astrophysics Data System (ADS)

    Fleury, Terry; Khurana, Himanshu; Welch, Von

    Control systems in the energy sector (e.g., supervisory control and data acquisition (SCADA) systems) involve a hierarchy of sensing, monitoring and control devices connected to centralized control stations or centers. The incorporation of commercial off-the-shelf technologies in energy control systems makes them vulnerable to cyber attacks. A taxonomy of cyber attacks against control systems can assist the energy sector in managing the cyber threat. This paper takes the first step towards a taxonomy by presenting a comprehensive model of attacks, vulnerabilities and damage related to control systems. The model is populated based on a survey of the technical literature from industry, academia and national laboratories.

  9. A Cyber-Attack Detection Model Based on Multivariate Analyses

    NASA Astrophysics Data System (ADS)

    Sakai, Yuto; Rinsaka, Koichiro; Dohi, Tadashi

    In the present paper, we propose a novel cyber-attack detection model based on two multivariate-analysis methods to the audit data observed on a host machine. The statistical techniques used here are the well-known Hayashi's quantification method IV and cluster analysis method. We quantify the observed qualitative audit event sequence via the quantification method IV, and collect similar audit event sequence in the same groups based on the cluster analysis. It is shown in simulation experiments that our model can improve the cyber-attack detection accuracy in some realistic cases where both normal and attack activities are intermingled.

  10. Recurrence of Panic Attacks after Influenza Vaccination: Two Case Reports

    PubMed Central

    Kim, Han-Joon; Jeon, Sang-Won; Yoon, Ho-Kyoung

    2016-01-01

    Human influenza is a contagious respiratory illness caused by the influenza virus. The influenza vaccination is recommended annually, but several adverse effects related to allergic reactions have been reported. Panic attacks are also known to occur, but no case of a panic attack adverse effect has been reported in South Korea. We present two cases of panic disorder patients whose symptoms were aggravated by the influenza vaccination. We assumed that dysregulation of T-lymphocytes in panic disorder patients could have a role in activating various kinds of cytokines and chemokines, which then can lead to panic attack aggravation. PMID:27776395

  11. Positive Proof.

    ERIC Educational Resources Information Center

    Auty, Geoffrey

    1988-01-01

    Presents experiments which show that in electrostatics there are logical reasons for describing charged materials as positive or negative. Indicates that static and current electricity are not separate areas of physics. Diagrams of experiments and circuits are included. (RT)

  12. C1-inhibitor therapy for hereditary angioedema attacks: prospective patient assessments of health-related quality of life.

    PubMed

    Bewtra, Againdra K; Levy, Robyn J; Jacobson, Kraig W; Wasserman, Richard L; Machnig, Thomas; Craig, Timothy J

    2012-01-01

    C1-inhibitor (INH) concentrate, which is recommended as first-line treatment for acute hereditary angioedema (HAE) attacks in many countries, was recently approved in the United States. We sought to solicit patients' feedback about their health-related quality of life (HRQoL) while being treated with C1-INH concentrate for acute HAE attacks under real-world conditions, as well as the personal impact of the availability of C1-INH on lifestyle and mental health domains. Subjects enrolled in an open-label study of C1-INH at 20 U/kg for acute HAE attacks were invited to participate in a prospectively designed survey to solicit "real-time" patient responses that were collected via an interactive voice response service or online with a personal computer. Eighteen subjects submitted 60 quarterly HRQoL and treatment impact survey responses over 29 months. Seventeen of 18 patients responding reported mean short form 12 HRQoL scores that were within a normal range. More than one-half indicated that C1-INH availability made them feel somewhat or much better, and >80% reported having a better outlook on the future and feeling more secure about the danger of life-threatening attacks. These data confirm a high level of HRQoL and a positive impact in lifestyle and emotional domains among patients who were treated for acute attacks of HAE with C1-INH concentrate.

  13. Degree-based attacks and defense strategies in complex networks

    NASA Astrophysics Data System (ADS)

    Yehezkel, Aviv; Cohen, Reuven

    2012-12-01

    We study the stability of random scale-free networks to degree-dependent attacks. We present analytical and numerical results to compute the critical fraction pc of nodes that need to be removed for destroying the network under this attack for different attack parameters. We study the effect of different defense strategies, based on the addition of a constant number of links on network robustness. We test defense strategies based on adding links to either low degree, middegree or high degree nodes. We find using analytical results and simulations that the middegree nodes defense strategy leads to the largest improvement to the network robustness against degree-based attacks. We also test these defense strategies on an internet autonomous systems map and obtain similar results.

  14. After-gate attack on a quantum cryptosystem

    NASA Astrophysics Data System (ADS)

    Wiechers, C.; Lydersen, L.; Wittmann, C.; Elser, D.; Skaar, J.; Marquardt, Ch; Makarov, V.; Leuchs, G.

    2011-01-01

    We present a method to control the detection events in quantum key distribution systems that use gated single-photon detectors. We employ bright pulses as faked states, timed to arrive at the avalanche photodiodes outside the activation time. The attack can remain unnoticed, since the faked states do not increase the error rate per se. This allows for an intercept-resend attack, where an eavesdropper transfers her detection events to the legitimate receiver without causing any errors. As a side effect, afterpulses, originating from accumulated charge carriers in the detectors, increase the error rate. We have experimentally tested detectors of the system id3110 (Clavis2) from ID Quantique. We identify the parameter regime in which the attack is feasible despite the side effect. Furthermore, we outline how simple modifications in the implementation can make the device immune to this attack.

  15. Vulnerability of complex networks under path-based attacks

    NASA Astrophysics Data System (ADS)

    Pu, Cun-Lai; Cui, Wei

    2015-02-01

    We investigate vulnerability of complex networks including model networks and real-world networks subject to path-based attacks. Specifically, we remove approximately the longest simple path from a network iteratively until there are no paths left in the network. We propose two algorithms, the random augmenting approach (RPA) and the Hamilton-path based approach (HPA), for finding the approximately longest simple path in a network. Results demonstrate that steps of longest-path attacks increase with network density linearly for random networks, while exponentially increasing for scale-free networks. The more homogeneous the degree distribution is, the more fragile the network, which is different from the previous results of node or edge attacks. HPA is generally more efficient than RPA in the longest-path attacks of complex networks. These findings further help us understand the vulnerability of complex systems, better protect complex systems, and design more tolerant complex systems.

  16. Sex Suffers for Younger Adults After Heart Attack

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_160722.html Sex Suffers for Younger Adults After Heart Attack Lack ... who don't talk to their doctors about sex in the first few weeks after a heart ...

  17. Heart Attack Symptoms | NIH MedlinePlus the Magazine

    MedlinePlus

    ... oxygen. If not treated quickly, the heart muscle fails to pump and begins to die. The most common heart attack symptom in men and women is chest pain or discomfort. However, women also are somewhat ...

  18. An unusual case of predation: dog pack or cougar attack?

    PubMed

    Fonseca, Gabriel M; Palacios, Rocío

    2013-01-01

    Injuries produced by animals are capable of leaving severe patterns and in some cases may result in the death of the attacked individual. Law enforcement authorities may come to erroneous conclusions about the source of the bites based on their awareness of animals present and similarities of the injuries to the untrained eye, with dreadful consequences. Expertise of a carnivore biologist and an odontologist that indentifies the particularities of bite marks may be useful for identifying the attacking species. We present the investigation of a fatal dog pack attack involving a 43-year-old man in Bell Ville (Argentina) where the evidence provided by a forensic dentist and a biologist was categorical for establishing the animal species involved. Because of the unusual characteristics of the wounds and the initial hypothesis made by local authorities of a cougar attack, habits and specific patterns of both dog pack and cougar predation on humans are discussed. PMID:22971181

  19. Taking vitamin D could halve the risk of asthma attacks.

    PubMed

    2016-09-21

    Cochrane library research has found that giving a daily oral vitamin D supplement to people with mild to moderate asthma reduced the risk of severe attacks requiring hospital admission or emergency department attendance from 6% to about 3%. PMID:27654533

  20. Polysomnographic findings in nights preceding a migraine attack.

    PubMed

    Göder, R; Fritzer, G; Kapsokalyvas, A; Kropp, P; Niederberger, U; Strenge, H; Gerber, W D; Aldenhoff, J B

    2001-02-01

    Sleep recordings were performed in eight patients to analyse sleep alterations preceding migraine attacks. Polysomnographic recordings from nights before an attack were compared with nights without following migraine. We analysed standard sleep parameters and electroencephalogram (EEG) power spectra. The main findings preceding migraine attacks were a significant decrease in the number of arousals, a decrease in rapid eye movement (REM) density, a significant decrease of beta power in the slow wave sleep, and a decrease of alpha power during the first REM period. The results suggest a decrease in cortical activation during sleep preceding migraine attacks. According to the models of sleep regulation, alterations in the function of aminergic or cholinergic brainstem nuclei have to be discussed. PMID:11298661

  1. Supersonic flow around circular cones at angles of attack

    NASA Technical Reports Server (NTRS)

    Ferri, Antonio

    1951-01-01

    The properties of conical flow without axial symmetry are analyzed. The flow around cones of circular cross section at small angles of attack is determined by correctly considering the effect of the entropy gradients in the flow.

  2. Quantum cloning attacks against PUF-based quantum authentication systems

    NASA Astrophysics Data System (ADS)

    Yao, Yao; Gao, Ming; Li, Mo; Zhang, Jian

    2016-08-01

    With the advent of physical unclonable functions (PUFs), PUF-based quantum authentication systems have been proposed for security purposes, and recently, proof-of-principle experiment has been demonstrated. As a further step toward completing the security analysis, we investigate quantum cloning attacks against PUF-based quantum authentication systems and prove that quantum cloning attacks outperform the so-called challenge-estimation attacks. We present the analytical expression of the false-accept probability by use of the corresponding optimal quantum cloning machines and extend the previous results in the literature. In light of these findings, an explicit comparison is made between PUF-based quantum authentication systems and quantum key distribution protocols in the context of cloning attacks. Moreover, from an experimental perspective, a trade-off between the average photon number and the detection efficiency is discussed in detail.

  3. Wing-alone aerodynamic characteristics at high angles of attack

    NASA Technical Reports Server (NTRS)

    Stallings, R. L., Jr.; Lamb, M.

    1981-01-01

    An experimental investigation has been conducted to determine wing-alone supersonic aerodynamic characteristics at high angles of attack. The family of wings tested varied in aspect ratio from 0.5 to 4.0 and taper ratio from 0.0 to 1.0. The wings were tested at angles of attack ranging from 0 to 60 deg and Mach numbers from 1.6 to 4.6. The aerodynamic characteristics were obtained by integrating local pressures measured over the wing surface. Comparison of these data with the limited available data from the literature indicate the present data are free of sting interference effects through the test range of angle of attack. Presented and discussed are results showing the effects of model geometry, Mach number and angle of attack on aerodynamic characteristics consisting of normal force, pitching moment, bending moment, longitudinal center-of-pressure locations, and lateral center-of-pressure locations.

  4. New records of Pipunculidae attacking proconiine sharpshooter (Auchenorrhyncha: Cicadellidae: Proconiini)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Five records of Pipunculidae (Diptera) attacking proconiine sharpshooters (Auchenorrhyncha: Cicadellidae) are documented here for the first time. Eudorylas alternatus (Cresson) is documented as a parasitoid of Cuerna obtusa Oman and Beamer, and Oncometopia orbona (Fabricius) is recorded as being at...

  5. VTAC: virtual terrain assisted impact assessment for cyber attacks

    NASA Astrophysics Data System (ADS)

    Argauer, Brian J.; Yang, Shanchieh J.

    2008-03-01

    Overwhelming intrusion alerts have made timely response to network security breaches a difficult task. Correlating alerts to produce a higher level view of intrusion state of a network, thus, becomes an essential element in network defense. This work proposes to analyze correlated or grouped alerts and determine their 'impact' to services and users of the network. A network is modeled as 'virtual terrain' where cyber attacks maneuver. Overlaying correlated attack tracks on virtual terrain exhibits the vulnerabilities exploited by each track and the relationships between them and different network entities. The proposed impact assessment algorithm utilizes the graph-based virtual terrain model and combines assessments of damages caused by the attacks. The combined impact scores allow to identify severely damaged network services and affected users. Several scenarios are examined to demonstrate the uses of the proposed Virtual Terrain Assisted Impact Assessment for Cyber Attacks (VTAC).

  6. Prevention of Tunneling Attack in endairA

    NASA Astrophysics Data System (ADS)

    Fanaei, Mohammad; Fanian, Ali; Berenjkoub, Mehdi

    endairA is one of the most secure on-demand ad hoc network source routing protocols which provides several defense mechanisms against so many types of attacks. In this paper, we prove the vulnerability of endairA to the tunneling attack by presenting an attack scenario against it. We also propose a new security mechanism to defend it against the tunneling attack by the utilization of the delay between receiving and sending its control packets computed locally by all intermediate nodes. Our proposed security mechanism can detect probable tunnels in the route as well as approximate locations of the adversarial nodes. It needs no time synchronization between mobile nodes of the network. It also does not change the number of control packets involved in endairA and only modifies the RREP messages slightly.

  7. Successful attack on permutation-parity-machine-based neural cryptography.

    PubMed

    Seoane, Luís F; Ruttor, Andreas

    2012-02-01

    An algorithm is presented which implements a probabilistic attack on the key-exchange protocol based on permutation parity machines. Instead of imitating the synchronization of the communicating partners, the strategy consists of a Monte Carlo method to sample the space of possible weights during inner rounds and an analytic approach to convey the extracted information from one outer round to the next one. The results show that the protocol under attack fails to synchronize faster than an eavesdropper using this algorithm.

  8. Security solution against denial of service attacks in BESIP system

    NASA Astrophysics Data System (ADS)

    Rezac, Filip; Voznak, Miroslav; Safarik, Jakub; Partila, Pavol; Tomala, Karel

    2013-05-01

    This article deals about embedded SIP communication server with an easy integration into the computer network based on open source solutions and its effective defense against the most frequent attack in the present - Denial of Service. The article contains brief introduction into the Bright Embedded Solution for IP Telephony - BESIP and describes the most common types of DoS attacks, which are applied on SIP elements of the VoIP infrastructure including the results of defensive mechanism that has been designed.

  9. Three cases giant panda attack on human at Beijing Zoo.

    PubMed

    Zhang, Peixun; Wang, Tianbing; Xiong, Jian; Xue, Feng; Xu, Hailin; Chen, Jianhai; Zhang, Dianying; Fu, Zhongguo; Jiang, Baoguo

    2014-01-01

    Panda is regarded as Chinese national treasure. Most people always thought they were cute and just ate bamboo and had never imagined a panda could be vicious. Giant panda attacks on human are rare. There, we present three cases of giant panda attacks on humans at the Panda House at Beijing Zoo from September 2006 to June 2009 to warn people of the giant panda's potentially dangerous behavior.

  10. Three cases giant panda attack on human at Beijing Zoo

    PubMed Central

    Zhang, Peixun; Wang, Tianbing; Xiong, Jian; Xue, Feng; Xu, Hailin; Chen, Jianhai; Zhang, Dianying; Fu, Zhongguo; Jiang, Baoguo

    2014-01-01

    Panda is regarded as Chinese national treasure. Most people always thought they were cute and just ate bamboo and had never imagined a panda could be vicious. Giant panda attacks on human are rare. There, we present three cases of giant panda attacks on humans at the Panda House at Beijing Zoo from September 2006 to June 2009 to warn people of the giant panda’s potentially dangerous behavior. PMID:25550978

  11. Captive tiger attack: case report and review of the literature.

    PubMed

    Schiller, Henry J; Cullinane, Daniel C; Sawyer, Mark D; Zietlow, Scott P

    2007-05-01

    Tigers, as well as other large predators, are being held in private settings with increasing frequency. Unregulated private "zoos" are cropping up in many rural and suburban settings across the country. The number of attacks from captive predators also is on the rise. This case highlights the potentially violent and aggressive nature of wild animals held in captivity. Treatment principals and wounding patterns of large cat attacks are emphasized.

  12. Risk Due to Radiological Terror Attacks With Natural Radionuclides

    SciTech Connect

    Friedrich, Steinhaeusler; Lyudmila, Zaitseva; Stan, Rydell

    2008-08-07

    The naturally occurring radionuclides radium (Ra-226) and polonium (Po-210) have the potential to be used for criminal acts. Analysis of international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (CSTO), operated at the University of Salzburg, shows that several acts of murder and terrorism with natural radionuclides have already been carried out in Europe and Russia. Five different modes of attack (T) are possible: (1) Covert irradiation of an individual in order to deliver a high individual dose; (2) Covert irradiation of a group of persons delivering a large collective dose; (3) Contamination of food or drink; (4) Generation of radioactive aerosols or solutions; (5) Combination of Ra-226 with conventional explosives (Dirty Bomb).This paper assesses the risk (R) of such criminal acts in terms of: (a) Probability of terrorist motivation deploying a certain attack mode T; (b) Probability of success by the terrorists for the selected attack mode T; (c) Primary damage consequence (C) to the attacked target (activity, dose); (d) Secondary damage consequence (C') to the attacked target (psychological and socio-economic effects); (e) Probability that the consequences (C, C') cannot be brought under control, resulting in a failure to manage successfully the emergency situation due to logistical and/or technical deficits in implementing adequate countermeasures. Extensive computer modelling is used to determine the potential impact of such a criminal attack on directly affected victims and on the environment.

  13. Willingness to pay for reductions in angina pectoris attacks.

    PubMed

    Kartman, B; Andersson, F; Johannesson, M

    1996-01-01

    To compare the costs of health care programs, with the benefits, the values of changes in health status must be expressed in monetary terms. The development of methods to estimate willingness to pay for changes in health status is therefore of interest. This paper reports the results of a contingent valuation study measuring willingness to pay for reductions in angina pectoris attacks. An innovative study design allowed analysis on the data on willingness to pay using two approaches, a binary question and a bidding-game technique. Percentage reductions in anginal attacks were varied randomly in different subsamples, and data were collected about angina pectoris status, attack rate, and income to test the internal validity of the contingent valuation method. Willingness to pay for a 50% reduction in the attack rate for three months was estimated to be about SEK 2,500 ($345) with the binary approach, and about SEK 2,100 ($290) using the bidding-game technique. Regression analyses showed that income, angina pectoris status, attack rate, and percentage reduction in attack rate were all related to willingness to pay, in agreement with the authors' hypothesis.

  14. Facial injuries following hyena attack in rural eastern Ethiopia.

    PubMed

    Fell, M J; Ayalew, Y; McClenaghan, F C; McGurk, M

    2014-12-01

    Hyenas are effective hunters and will consider humans as potential prey if the need and opportunity arise. This study describes the circumstances of hyena attacks, the patterns of injuries sustained, and reconstruction in a resource-poor setting. As part of a charitable surgical mission to Ethiopia in 2012, 45 patients with facial deformities were reviewed, of whom four were victims of hyena attacks. A semi-structured interview was performed to ascertain the circumstances of the attack and the subsequent consequences. The age of the victims at the time of attack varied from 5 to 50 years. The attacks occurred when the victims were alone and vulnerable and took place in outdoor open spaces, during the evening or at night. The initial lunge was made to the facial area; if the jaws closed on the facial bones they were crushed, but in all cases the soft tissues were grasped and torn from the underlying bone. Reconstruction was dictated by the extent of soft tissue loss but could normally be obtained by use of local or regional flaps. Hyenas have been shown to attack humans in a predictable way and cause injuries that typically involve the soft tissues of the face. PMID:25132572

  15. A comparative analysis of network robustness against different link attacks

    NASA Astrophysics Data System (ADS)

    Duan, Boping; Liu, Jing; Zhou, Mingxing; Ma, Liangliang

    2016-04-01

    Recently, the study of optimizing network robustness has attracted increasing attentions, and the constraint that every node's degree cannot be changed is considered. Although this constraint maintains the node degree distribution consistently in order to reserve the structure of networks, it makes the network structure be lack of flexibility since many network structure always transform in the modern society. Given this consideration, in this paper, we analyze the robustness of networks through setting a new constraint; that is, only the number of edges should be unchanged. Then, we use the link-robustness index (Rl) as the measure of the network robustness against either random failures or intentional attacks, and make a comparative analysis of network robustness against different types of link attacks. Moreover, we use four types of networks as initial networks, namely scale-free networks, random networks, regular networks, and small-world networks. The experimental results show that the values of robustness measures for the optimized networks starting from different initial networks are similar under different link attacks, but the network topologies may be different. That is to say, networks with different topologies may have similar robustness in terms of the robustness measures. We also find that the optimized networks obtained by one link attack may not robust against other link attacks, sometimes, even weaker than the original networks. Therefore, before building networks, it is better to study which type of link attacks may happen.

  16. Quantum hacking: attacking practical quantum key distribution systems

    NASA Astrophysics Data System (ADS)

    Qi, Bing; Fung, Chi-Hang Fred; Zhao, Yi; Ma, Xiongfeng; Tamaki, Kiyoshi; Chen, Christine; Lo, Hoi-Kwong

    2007-09-01

    Quantum key distribution (QKD) can, in principle, provide unconditional security based on the fundamental laws of physics. Unfortunately, a practical QKD system may contain overlooked imperfections and violate some of the assumptions in a security proof. Here, we report two types of eavesdropping attacks against a practical QKD system. The first one is "time-shift" attack, which is applicable to QKD systems with gated single photon detectors (SPDs). In this attack, the eavesdropper, Eve, exploits the time mismatch between the open windows of the two SPDs. She can acquire a significant amount of information on the final key by simply shifting the quantum signals forwards or backwards in time domain. Our experimental results in [9] with a commercial QKD system demonstrate that, under this attack, the original QKD system is breakable. This is the first experimental demonstration of a feasible attack against a commercial QKD system. This is a surprising result. The second one is "phase-remapping" attack [10]. Here, Eve exploits the fact that a practical phase modulator has a finite response time. In principle, Eve could change the encoded phase value by time-shifting the signal pulse relative to the reference pulse.

  17. Facial injuries following hyena attack in rural eastern Ethiopia.

    PubMed

    Fell, M J; Ayalew, Y; McClenaghan, F C; McGurk, M

    2014-12-01

    Hyenas are effective hunters and will consider humans as potential prey if the need and opportunity arise. This study describes the circumstances of hyena attacks, the patterns of injuries sustained, and reconstruction in a resource-poor setting. As part of a charitable surgical mission to Ethiopia in 2012, 45 patients with facial deformities were reviewed, of whom four were victims of hyena attacks. A semi-structured interview was performed to ascertain the circumstances of the attack and the subsequent consequences. The age of the victims at the time of attack varied from 5 to 50 years. The attacks occurred when the victims were alone and vulnerable and took place in outdoor open spaces, during the evening or at night. The initial lunge was made to the facial area; if the jaws closed on the facial bones they were crushed, but in all cases the soft tissues were grasped and torn from the underlying bone. Reconstruction was dictated by the extent of soft tissue loss but could normally be obtained by use of local or regional flaps. Hyenas have been shown to attack humans in a predictable way and cause injuries that typically involve the soft tissues of the face.

  18. Modeling Partial Attacks with Alloy (Transcript of Discussion)

    NASA Astrophysics Data System (ADS)

    Lin, Amerson

    The reason we went into this research, was that we found that partial attacks were extremely hard to model in terms of a language that could be used by an automated tool. Now there are three reasons why this is so. The first is that it is hard to identify these attacks even by hand, because you have to be really creative in thinking, what constitutes a reduction in entropy of the secret, that is significant, because a partial attack is really anything that reduces entropy, it's just that it does not reduce the entropy to zero, which would be a case of a complete attack. Next, it's hard to describe that in a formal language, part of that problem comes from the definition, you have to define what you want to be the goal, if the secret is the entire password, then getting one letter is pretty much a partial attack, but if the secret is that one letter, then getting that one letter is a complete attack. And lastly, applying that logic, how do you measure entropy, how do you measure information leakage, that's also very difficult.

  19. Vulnerability of water supply systems to cyber-physical attacks

    NASA Astrophysics Data System (ADS)

    Galelli, Stefano; Taormina, Riccardo; Tippenhauer, Nils; Salomons, Elad; Ostfeld, Avi

    2016-04-01

    The adoption of smart meters, distributed sensor networks and industrial control systems has largely improved the level of service provided by modern water supply systems. Yet, the progressive computerization exposes these critical infrastructures to cyber-physical attacks, which are generally aimed at stealing critical information (cyber-espionage) or causing service disruption (denial-of-service). Recent statistics show that water and power utilities are undergoing frequent attacks - such as the December power outage in Ukraine - , attracting the interest of operators and security agencies. Taking the security of Water Distribution Networks (WDNs) as domain of study, our work seeks to characterize the vulnerability of WDNs to cyber-physical attacks, so as to conceive adequate defense mechanisms. We extend the functionality of EPANET, which models hydraulic and water quality processes in pressurized pipe networks, to include a cyber layer vulnerable to repeated attacks. Simulation results on a medium-scale network show that several hydraulic actuators (valves and pumps, for example) can be easily attacked, causing both service disruption - i.e., water spillage and loss of pressure - and structural damages - e.g., pipes burst. Our work highlights the need for adequate countermeasures, such as attacks detection and reactive control systems.

  20. Modeling attacker-defender interactions in information networks.

    SciTech Connect

    Collins, Michael Joseph

    2010-09-01

    The simplest conceptual model of cybersecurity implicitly views attackers and defenders as acting in isolation from one another: an attacker seeks to penetrate or disrupt a system that has been protected to a given level, while a defender attempts to thwart particular attacks. Such a model also views all non-malicious parties as having the same goal of preventing all attacks. But in fact, attackers and defenders are interacting parts of the same system, and different defenders have their own individual interests: defenders may be willing to accept some risk of successful attack if the cost of defense is too high. We have used game theory to develop models of how non-cooperative but non-malicious players in a network interact when there is a substantial cost associated with effective defensive measures. Although game theory has been applied in this area before, we have introduced some novel aspects of player behavior in our work, including: (1) A model of how players attempt to avoid the costs of defense and force others to assume these costs; (2) A model of how players interact when the cost of defending one node can be shared by other nodes; and (3) A model of the incentives for a defender to choose less expensive, but less effective, defensive actions.

  1. Sleep panic attacks: a micro-movement analysis.

    PubMed

    Brown, Terry M; Uhde, Thomas W

    2003-01-01

    Earlier work by our group and others has pointed to a role for movement during sleep in sleep-panic attacks. Specifically, our group has reported that panic disorder patients, as a group, appear to move more during sleep than age-matched controls, whereas the subgroup of panic disorder who "panic" during sleep move less on the nights they experience sleep-panic attacks than they do on nights without sleep-panic attacks. We studied the movement of sleep-panic patients in a more detailed fashion with more than one sleep movement index. Fourteen patients with sleep-panic attacks were compared with 14 waking panic patients, 13 social phobic patients, and 14 normal controls. Subjects from the other groups were age matched to the sleep-panic group. Their comparison study night corresponded to the night number of the sleep-panic attack. Sleep-panic patients did move less on panic nights than did the normal controls on the corresponding sleep-panic night according to two separate sleep movement indices. Although not statistically significant, sleep-panic patients also moved less on their panic night than did either of the other anxious groups on corresponding nights. Rechtshaffen and Kales' Movement Time (MT) measure appears to overestimate actual min of movement during sleep in all subjects. The movement noted in sleep-panic patients may have some role in the pathophysiology of sleep-panic attacks. A possible mechanism is explained.

  2. Forensic analysis of nonlinear collusion attacks for multimedia fingerprinting.

    PubMed

    Zhao, H Vicky; Wu, Min; Wang, Z Jane; Liu, K J Ray

    2005-05-01

    Digital fingerprinting is a technology for tracing the distribution of multimedia content and protecting them from unauthorized redistribution. Unique identification information is embedded into each distributed copy of multimedia signal and serves as a digital fingerprint. Collusion attack is a cost-effective attack against digital fingerprinting, where colluders combine several copies with the same content but different fingerprints to remove or attenuate the original fingerprints. In this paper, we investigate the average collusion attack and several basic nonlinear collusions on independent Gaussian fingerprints, and study their effectiveness and the impact on the perceptual quality. With unbounded Gaussian fingerprints, perceivable distortion may exist in the fingerprinted copies as well as the copies after the collusion attacks. In order to remove this perceptual distortion, we introduce bounded Gaussian-like fingerprints and study their performance under collusion attacks. We also study several commonly used detection statistics and analyze their performance under collusion attacks. We further propose a preprocessing technique of the extracted fingerprints specifically for collusion scenarios to improve the detection performance.

  3. Risk Due to Radiological Terror Attacks With Natural Radionuclides

    NASA Astrophysics Data System (ADS)

    Friedrich, Steinhäusler; Stan, Rydell; Lyudmila, Zaitseva

    2008-08-01

    The naturally occurring radionuclides radium (Ra-226) and polonium (Po-210) have the potential to be used for criminal acts. Analysis of international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (CSTO), operated at the University of Salzburg, shows that several acts of murder and terrorism with natural radionuclides have already been carried out in Europe and Russia. Five different modes of attack (T) are possible: (1) Covert irradiation of an individual in order to deliver a high individual dose; (2) Covert irradiation of a group of persons delivering a large collective dose; (3) Contamination of food or drink; (4) Generation of radioactive aerosols or solutions; (5) Combination of Ra-226 with conventional explosives (Dirty Bomb). This paper assesses the risk (R) of such criminal acts in terms of: (a) Probability of terrorist motivation deploying a certain attack mode T; (b) Probability of success by the terrorists for the selected attack mode T; (c) Primary damage consequence (C) to the attacked target (activity, dose); (d) Secondary damage consequence (C') to the attacked target (psychological and socio-economic effects); (e) Probability that the consequences (C, C') cannot be brought under control, resulting in a failure to manage successfully the emergency situation due to logistical and/or technical deficits in implementing adequate countermeasures. Extensive computer modelling is used to determine the potential impact of such a criminal attack on directly affected victims and on the environment.

  4. Human behaviour can trigger large carnivore attacks in developed countries

    PubMed Central

    Penteriani, Vincenzo; Delgado, María del Mar; Pinchera, Francesco; Naves, Javier; Fernández-Gil, Alberto; Kojola, Ilpo; Härkönen, Sauli; Norberg, Harri; Frank, Jens; Fedriani, José María; Sahlén, Veronica; Støen, Ole-Gunnar; Swenson, Jon E.; Wabakken, Petter; Pellegrini, Mario; Herrero, Stephen; López-Bao, José Vicente

    2016-01-01

    The media and scientific literature are increasingly reporting an escalation of large carnivore attacks on humans in North America and Europe. Although rare compared to human fatalities by other wildlife, the media often overplay large carnivore attacks on humans, causing increased fear and negative attitudes towards coexisting with and conserving these species. Although large carnivore populations are generally increasing in developed countries, increased numbers are not solely responsible for the observed rise in the number of attacks by large carnivores. Here we show that an increasing number of people are involved in outdoor activities and, when doing so, some people engage in risk-enhancing behaviour that can increase the probability of a risky encounter and a potential attack. About half of the well-documented reported attacks have involved risk-enhancing human behaviours, the most common of which is leaving children unattended. Our study provides unique insight into the causes, and as a result the prevention, of large carnivore attacks on people. Prevention and information that can encourage appropriate human behaviour when sharing the landscape with large carnivores are of paramount importance to reduce both potentially fatal human-carnivore encounters and their consequences to large carnivores. PMID:26838467

  5. Human behaviour can trigger large carnivore attacks in developed countries.

    PubMed

    Penteriani, Vincenzo; Delgado, María del Mar; Pinchera, Francesco; Naves, Javier; Fernández-Gil, Alberto; Kojola, Ilpo; Härkönen, Sauli; Norberg, Harri; Frank, Jens; Fedriani, José María; Sahlén, Veronica; Støen, Ole-Gunnar; Swenson, Jon E; Wabakken, Petter; Pellegrini, Mario; Herrero, Stephen; López-Bao, José Vicente

    2016-01-01

    The media and scientific literature are increasingly reporting an escalation of large carnivore attacks on humans in North America and Europe. Although rare compared to human fatalities by other wildlife, the media often overplay large carnivore attacks on humans, causing increased fear and negative attitudes towards coexisting with and conserving these species. Although large carnivore populations are generally increasing in developed countries, increased numbers are not solely responsible for the observed rise in the number of attacks by large carnivores. Here we show that an increasing number of people are involved in outdoor activities and, when doing so, some people engage in risk-enhancing behaviour that can increase the probability of a risky encounter and a potential attack. About half of the well-documented reported attacks have involved risk-enhancing human behaviours, the most common of which is leaving children unattended. Our study provides unique insight into the causes, and as a result the prevention, of large carnivore attacks on people. Prevention and information that can encourage appropriate human behaviour when sharing the landscape with large carnivores are of paramount importance to reduce both potentially fatal human-carnivore encounters and their consequences to large carnivores. PMID:26838467

  6. Larval defense against attack from parasitoid wasps requires nociceptive neurons.

    PubMed

    Robertson, Jessica L; Tsubouchi, Asako; Tracey, W Daniel

    2013-01-01

    Parasitoid wasps are a fierce predator of Drosophila larvae. Female Leptopilina boulardi (LB) wasps use a sharp ovipositor to inject eggs into the bodies of Drosophila melanogaster larvae. The wasp then eats the Drosophila larva alive from the inside, and an adult wasp ecloses from the Drosophila pupal case instead of a fly. However, the Drosophila larvae are not defenseless as they may resist the attack of the wasps through somatosensory-triggered behavioral responses. Here we describe the full range of behaviors performed by the larval prey in immediate response to attacks by the wasps. Our results suggest that Drosophila larvae primarily sense the wasps using their mechanosensory systems. The range of behavioral responses included both "gentle touch" like responses as well as nociceptive responses. We found that the precise larval response depended on both the somatotopic location of the attack, and whether or not the larval cuticle was successfully penetrated during the course of the attack. Interestingly, nociceptive responses are more likely to be triggered by attacks in which the cuticle had been successfully penetrated by the wasp. Finally, we found that the class IV neurons, which are necessary for mechanical nociception, were also necessary for a nociceptive response to wasp attacks. Thus, the class IV neurons allow for a nociceptive behavioral response to a naturally occurring predator of Drosophila.

  7. Enhancing community integrity of networks against multilevel targeted attacks

    NASA Astrophysics Data System (ADS)

    Ma, Lijia; Gong, Maoguo; Cai, Qing; Jiao, Licheng

    2013-08-01

    The community structure and the robustness are two important properties of networks for analyzing the functionality of complex systems. The community structure is crucial to understand the potential functionality of complex systems, while the robustness is indispensable to protect the functionality of complex systems from malicious attacks. When a network suffers from an unpredictable attack, its structural integrity would be damaged. Earlier studies focused on the integrity of the node structure or the edge structure when a network suffers from a single-level malicious attack on the nodes or the edges. In this study, we model the attack on the network as a two-level targeted one. Then, we propose a community robustness index to evaluate the integrality of the community structure when the network suffers from the modeled attack. The proposed index plays an important role in analyzing the ability of the real systems to resist unpredictable failures. Finally, based on the proposed community robustness index, a greedy algorithm is devised to mitigate the network attack. Experiments on three real network systems show that with minor changes in links the community robustness of networks can be greatly improved. The results also demonstrate that the community structures in the optimized networks remain practically unchanged compared with the original ones.

  8. Larval Defense against Attack from Parasitoid Wasps Requires Nociceptive Neurons

    PubMed Central

    Robertson, Jessica L.; Tsubouchi, Asako; Tracey, W. Daniel

    2013-01-01

    Parasitoid wasps are a fierce predator of Drosophila larvae. Female Leptopilina boulardi (LB) wasps use a sharp ovipositor to inject eggs into the bodies of Drosophila melanogaster larvae. The wasp then eats the Drosophila larva alive from the inside, and an adult wasp ecloses from the Drosophila pupal case instead of a fly. However, the Drosophila larvae are not defenseless as they may resist the attack of the wasps through somatosensory-triggered behavioral responses. Here we describe the full range of behaviors performed by the larval prey in immediate response to attacks by the wasps. Our results suggest that Drosophila larvae primarily sense the wasps using their mechanosensory systems. The range of behavioral responses included both “gentle touch” like responses as well as nociceptive responses. We found that the precise larval response depended on both the somatotopic location of the attack, and whether or not the larval cuticle was successfully penetrated during the course of the attack. Interestingly, nociceptive responses are more likely to be triggered by attacks in which the cuticle had been successfully penetrated by the wasp. Finally, we found that the class IV neurons, which are necessary for mechanical nociception, were also necessary for a nociceptive response to wasp attacks. Thus, the class IV neurons allow for a nociceptive behavioral response to a naturally occurring predator of Drosophila. PMID:24205297

  9. Impact modeling and prediction of attacks on cyber targets

    NASA Astrophysics Data System (ADS)

    Khalili, Aram; Michalk, Brian; Alford, Lee; Henney, Chris; Gilbert, Logan

    2010-04-01

    In most organizations, IT (information technology) infrastructure exists to support the organization's mission. The threat of cyber attacks poses risks to this mission. Current network security research focuses on the threat of cyber attacks to the organization's IT infrastructure; however, the risks to the overall mission are rarely analyzed or formalized. This connection of IT infrastructure to the organization's mission is often neglected or carried out ad-hoc. Our work bridges this gap and introduces analyses and formalisms to help organizations understand the mission risks they face from cyber attacks. Modeling an organization's mission vulnerability to cyber attacks requires a description of the IT infrastructure (network model), the organization mission (business model), and how the mission relies on IT resources (correlation model). With this information, proper analysis can show which cyber resources are of tactical importance in a cyber attack, i.e., controlling them enables a large range of cyber attacks. Such analysis also reveals which IT resources contribute most to the organization's mission, i.e., lack of control over them gravely affects the mission. These results can then be used to formulate IT security strategies and explore their trade-offs, which leads to better incident response. This paper presents our methodology for encoding IT infrastructure, organization mission and correlations, our analysis framework, as well as initial experimental results and conclusions.

  10. Understanding public confidence in government to prevent terrorist attacks.

    SciTech Connect

    Baldwin, T. E.; Ramaprasad, A,; Samsa, M. E.; Decision and Information Sciences; Univ. of Illinois at Chicago

    2008-04-02

    A primary goal of terrorism is to instill a sense of fear and vulnerability in a population and to erode its confidence in government and law enforcement agencies to protect citizens against future attacks. In recognition of its importance, the Department of Homeland Security includes public confidence as one of the principal metrics used to assess the consequences of terrorist attacks. Hence, a detailed understanding of the variations in public confidence among individuals, terrorist event types, and as a function of time is critical to developing this metric. In this exploratory study, a questionnaire was designed, tested, and administered to small groups of individuals to measure public confidence in the ability of federal, state, and local governments and their public safety agencies to prevent acts of terrorism. Data was collected from three groups before and after they watched mock television news broadcasts portraying a smallpox attack, a series of suicide bomber attacks, a refinery explosion attack, and cyber intrusions on financial institutions, resulting in identity theft. Our findings are: (a) although the aggregate confidence level is low, there are optimists and pessimists; (b) the subjects are discriminating in interpreting the nature of a terrorist attack, the time horizon, and its impact; (c) confidence recovery after a terrorist event has an incubation period; and (d) the patterns of recovery of confidence of the optimists and the pessimists are different. These findings can affect the strategy and policies to manage public confidence after a terrorist event.

  11. Transgenic plants protected from insect attack

    NASA Astrophysics Data System (ADS)

    Vaeck, Mark; Reynaerts, Arlette; Höfte, Herman; Jansens, Stefan; de Beuckeleer, Marc; Dean, Caroline; Zabeau, Marc; Montagu, Marc Van; Leemans, Jan

    1987-07-01

    The Gram-positive bacterium Bacillus thuringiensis produces proteins which are specifically toxic to a variety of insect species. Modified genes have been derived from bt2, a toxin gene cloned from one Bacillus strain. Transgenic tobacco plants expressing these genes synthesize insecticidal proteins which protect them from feeding damage by larvae of the tobacco hornworm.

  12. Position indicator

    DOEpatents

    Tanner, David E.

    1981-01-01

    A nuclear reactor system is described in which a position indicator is provided for detecting and indicating the position of a movable element inside a pressure vessel. The movable element may be a valve element or similar device which moves about an axis. Light from a light source is transmitted from a source outside the pressure vessel to a first region inside the pressure vessel in alignment with the axis of the movable element. The light is redirected by a reflector prism to a second region displaced radially from the first region. The reflector prism moves in response to movement of the movable element about its axis such that the second region moves arcuately with respect to the first region. Sensors are arrayed in an arc corresponding to the arc of movement of the second region and signals are transmitted from the sensors to the exterior of the reactor vessel to provide indication of the position of the movable element.

  13. Attack methodology Analysis: SQL Injection Attacks and Their Applicability to Control Systems

    SciTech Connect

    Bri Rolston

    2005-09-01

    Database applications have become a core component in control systems and their associated record keeping utilities. Traditional security models attempt to secure systems by isolating core software components and concentrating security efforts against threats specific to those computers or software components. Database security within control systems follows these models by using generally independent systems that rely on one another for proper functionality. The high level of reliance between the two systems creates an expanded threat surface. To understand the scope of a threat surface, all segments of the control system, with an emphasis on entry points, must be examined. The communication link between data and decision layers is the primary attack surface for SQL injection. This paper facilitates understanding what SQL injection is and why it is a significant threat to control system environments.

  14. Being, thinking, creating: when war attacks the setting and the transference counter-attacks.

    PubMed

    Khair Badawi, Marie-Thérèse; Badawi, Marie-Thérèse Khair

    2011-04-01

    When trauma enters into the reality of the analyst and of the analysand, when it attacks the setting, what becomes of the analyst's role? How can transformations be brought about? With reference to three clinical situations, the author attempts to explore how the articulation between transference and countertransference - the inter-relation - structures the situation; the analyst must remain in his or her role as analyst through managing to create and to reflect upon the clinical aspects of that situation when faced with the unpredictability of what war brings in its wake. It then becomes possible to see how the work of the negative can be confined to the outer limits of the setting.

  15. Collusive attacks to "circle-type" multi-party quantum key agreement protocols

    NASA Astrophysics Data System (ADS)

    Liu, Bin; Xiao, Di; Jia, Heng-Yue; Liu, Run-Zong

    2016-05-01

    We find that existing multi-party quantum key agreement (MQKA) protocols designed for fairness of the key are, in fact, unfair. Our analysis shows that these protocols are sensitive to collusive attacks; that is, dishonest participants can collaborate in predetermining the key without being detected. In fact, the transmission structures of the quantum particles in those unfair MQKA protocols, three of which have already been analyzed, have much in common. We call these unfair MQKA protocols circle-type MQKA protocols. Likewise, the transmission structures of the quantum particles in MQKA protocols that can resist collusive attacks are also similar. We call such protocols complete-graph-type MQKA protocols. A MQKA protocol also exists that can resist the above attacks but is still not fair, and we call it the tree-type MQKA protocol. We first point out a common, easily missed loophole that severely compromises the fairness of present circle-type MQKA protocols. Then we show that two dishonest participants at special positions can totally predetermine the key generated by circle-type MQKA protocols. We anticipate that our observations will contribute to secure and fair MQKA protocols, especially circle-type protocols.

  16. Preventing shoulder-surfing attack with the concept of concealing the password objects' information.

    PubMed

    Ho, Peng Foong; Kam, Yvonne Hwei-Syn; Wee, Mee Chin; Chong, Yu Nam; Por, Lip Yee

    2014-01-01

    Traditionally, picture-based password systems employ password objects (pictures/icons/symbols) as input during an authentication session, thus making them vulnerable to "shoulder-surfing" attack because the visual interface by function is easily observed by others. Recent software-based approaches attempt to minimize this threat by requiring users to enter their passwords indirectly by performing certain mental tasks to derive the indirect password, thus concealing the user's actual password. However, weaknesses in the positioning of distracter and password objects introduce usability and security issues. In this paper, a new method, which conceals information about the password objects as much as possible, is proposed. Besides concealing the password objects and the number of password objects, the proposed method allows both password and distracter objects to be used as the challenge set's input. The correctly entered password appears to be random and can only be derived with the knowledge of the full set of password objects. Therefore, it would be difficult for a shoulder-surfing adversary to identify the user's actual password. Simulation results indicate that the correct input object and its location are random for each challenge set, thus preventing frequency of occurrence analysis attack. User study results show that the proposed method is able to prevent shoulder-surfing attack.

  17. Experimental investigation of forebody and wing leading-edge vortex interactions at high angles of attack

    NASA Technical Reports Server (NTRS)

    Erickson, G. E.; Gilbert, W. P.

    1983-01-01

    An experimental investigation was conducted to assess the vortex flow-field interactions on an advanced, twin-jet fighter aircraft configuration at high angles of attack. Flow-field surveys were conducted on a small-scale model in the Northrop 0.41 - by 0.60-meter water tunnel and, where appropriate, the qualitative observations were correlated with low-speed wind tunnel data trends obtained on a large-scale model of the advanced fighter in the NASA Langley Research Center 30- by 60-foot (9.1- by 18.3-meter) facility. Emphasis was placed on understanding the interactions of the forebody and LEX-wing vortical flows, defining the effects on rolling moment variation with sideslip, and identifying modifications to control or regulate the vortex interactions at high angles of attack. The water tunnel flow visualization results and wind tunnel data trend analysis revealed the potential for strong interactions between the forebody and LEX vortices at high angles of attack. In particular, the forebody flow development near the nose could be controlled by means of carefully-positioned radome strakes. The resultant strake-induced flow-field changes were amplified downstream by the more powerful LEX vortical motions with subsequent large effects on wing flow separation characteristics.

  18. Cultural Explanations of Sleep Paralysis in Italy: The Pandafeche Attack and Associated Supernatural Beliefs.

    PubMed

    Jalal, Baland; Romanelli, Andrea; Hinton, Devon E

    2015-12-01

    The current study examines cultural explanations regarding sleep paralysis (SP) in Italy. The study explores (1) whether the phenomenology of SP generates culturally specific interpretations and causal explanations and (2) what are the beliefs and local traditions associated with such cultural explanations. The participants were Italian nationals from the general population (n = 68) recruited in the region of Abruzzo, Italy. All participants had experienced at least one lifetime episode of SP. The sleep paralysis experiences and phenomenology questionnaire were orally administered to participants. We found a multilayered cultural interpretation of SP, namely the Pandafeche attack, associated with various supernatural beliefs. Thirty-eight percent of participants believed that this supernatural being, the Pandafeche-often referred to as an evil witch, sometimes as a ghost-like spirit or a terrifying humanoid cat-might have caused their SP. Twenty-four percent of all participants sensed the Pandafeche was present during their SP. Strategies to prevent Pandafeche attack included sleeping in supine position, placing a broom by the bedroom door, or putting a pile of sand by the bed. Case studies are presented to illustrate the study findings. The Pandafeche attack thus constitutes a culturally specific, supernatural interpretation of the phenomenology of SP in the Abruzzo region of Italy.

  19. Preventing Shoulder-Surfing Attack with the Concept of Concealing the Password Objects' Information

    PubMed Central

    Ho, Peng Foong; Kam, Yvonne Hwei-Syn; Wee, Mee Chin

    2014-01-01

    Traditionally, picture-based password systems employ password objects (pictures/icons/symbols) as input during an authentication session, thus making them vulnerable to “shoulder-surfing” attack because the visual interface by function is easily observed by others. Recent software-based approaches attempt to minimize this threat by requiring users to enter their passwords indirectly by performing certain mental tasks to derive the indirect password, thus concealing the user's actual password. However, weaknesses in the positioning of distracter and password objects introduce usability and security issues. In this paper, a new method, which conceals information about the password objects as much as possible, is proposed. Besides concealing the password objects and the number of password objects, the proposed method allows both password and distracter objects to be used as the challenge set's input. The correctly entered password appears to be random and can only be derived with the knowledge of the full set of password objects. Therefore, it would be difficult for a shoulder-surfing adversary to identify the user's actual password. Simulation results indicate that the correct input object and its location are random for each challenge set, thus preventing frequency of occurrence analysis attack. User study results show that the proposed method is able to prevent shoulder-surfing attack. PMID:24991649

  20. Cultural Explanations of Sleep Paralysis in Italy: The Pandafeche Attack and Associated Supernatural Beliefs.

    PubMed

    Jalal, Baland; Romanelli, Andrea; Hinton, Devon E

    2015-12-01

    The current study examines cultural explanations regarding sleep paralysis (SP) in Italy. The study explores (1) whether the phenomenology of SP generates culturally specific interpretations and causal explanations and (2) what are the beliefs and local traditions associated with such cultural explanations. The participants were Italian nationals from the general population (n = 68) recruited in the region of Abruzzo, Italy. All participants had experienced at least one lifetime episode of SP. The sleep paralysis experiences and phenomenology questionnaire were orally administered to participants. We found a multilayered cultural interpretation of SP, namely the Pandafeche attack, associated with various supernatural beliefs. Thirty-eight percent of participants believed that this supernatural being, the Pandafeche-often referred to as an evil witch, sometimes as a ghost-like spirit or a terrifying humanoid cat-might have caused their SP. Twenty-four percent of all participants sensed the Pandafeche was present during their SP. Strategies to prevent Pandafeche attack included sleeping in supine position, placing a broom by the bedroom door, or putting a pile of sand by the bed. Case studies are presented to illustrate the study findings. The Pandafeche attack thus constitutes a culturally specific, supernatural interpretation of the phenomenology of SP in the Abruzzo region of Italy. PMID:25802016

  1. Multiple sclerosis: long time modifications of seasonal differences in the frequency of clinical attacks.

    PubMed

    Iuliano, Gerardo

    2012-10-01

    Previous papers show different patterns of seasonal distribution of multiple sclerosis attacks. This paper compares long-time modifications. Salerno MS registry (Southern Italy), was reviewed, including 189 patients, age onset 12-51 years (mean = 29.88, SD = 8.4), disease duration mean = 6.94 years (1-29), attacks mean = 4.5 (2-25, SD = 3.41). Data were stratified by decades. Number of events/month was analyzed by odds ratios and forecast modeling (ARIMA); means by ANOVA and post hoc tests, and correlations by multiple regression. We found 869 relapses: J = 72, F = 48, M = 122, A = 75, M = 68, Jn = 59, Jl = 81, A = 74, S = 63, O = 70, N = 72, D = 65. In 2001-2008 there was one significant peak (March); in 1991-2000 many (greatest = July), and in 1984-1990, one positive (June), one negative (April). Differences between 1990s and 2000s are significant. It is the first study addressing ultradecennal trends, and finding that the season distribution of MS attacks is significantly different: the study confirms frequency peaks in early spring and summer, but they are different in different decades. This significant ultra-decade difference might support hypotheses more linked to infections or toxic substances than to sunlight, UV, or similar. PMID:22143944

  2. Factors governing risk of cougar attacks on humans

    USGS Publications Warehouse

    Mattson, David; Logan, Kenneth; Sweanor, Linda

    2011-01-01

    Since the 1980s wildlife managers in the United States and Canada have expressed increasing concern about the physical threat posed by cougars (Puma concolor) to humans. We developed a conceptual framework and analyzed 386 human–cougar encounters (29 fatal attacks, 171 instances of nonfatal contact, and 186 close-threatening encounters) to provide information relevant to public safety. We conceived of human injury and death as the outcome of 4 transitions affected by different suites of factors: (1) a human encountering a cougar: (2) given an encounter, odds that the cougar would be aggressive; (3) given aggression, odds that the cougar would attack; and (4) given an attack, odds that the human would die. We developed multivariable logistic regression models to explain variation in odds at transitions three and four using variables pertaining to characteristics of involved people and cougars. Young (≤ 2.5 years) or unhealthy (by weight, condition, or disease) cougars were more likely than any others to be involved in close (typically <5 m) encounters that threatened the involved person. Of cougars in close encounters, females were more likely than males to attack, and of attacking animals, adults were more likely than juveniles to kill the victim (32% versus 9% fatality, respectively). During close encounters, victims who used a weapon killed the involved cougar in 82% of cases. Other mitigating behaviors (e.g., yelling, backing away, throwing objects, increasing stature) also substantially lessened odds of attack. People who were moving quickly or erratically when an encounter happened (running, playing, skiing, snowshoeing, biking, ATV-riding) were more likely to be attacked and killed compared to people who were less active (25% versus 8% fatality). Children (≤ 10 years) were more likely than single adults to be attacked, but intervention by people of any age reduced odds of a child’s death by 4.6×. Overall, cougar attacks on people in Canada and the

  3. Value of ABCD2-F in Predicting Cerebral Ischemic Attacks: Three Months Follow-Up after the Primary Attack.

    PubMed

    Chardoli, Mojtaba; Firoozabadi, Nader H; Nouri, Mohsen; Rahimi-Movaghar, Vafa

    2016-06-01

    Cerebrovascular attack (CVA) and transient ischemic attack (TIA) are major causes of emergency department visits around the globe. A significant number of these patients may experience repeat attacks if left untreated. Several risk stratifying scoring systems have been developed in recent years to point out the high risk patients. ABCD2 is based on age, blood pressure, clinical status, diabetes mellitus, and duration of symptoms and is used commonly for this purpose. In this study, we were to enhance its sensitivity and specificity with the addition of another criterion namely atrial fibrillation and making ABCD2-F. A prospective study in two hospitals was performed and 138 patients diagnosed with TIA/CVA were enrolled. Demographic, clinical, and paraclinical data of all patients were registered. All patients were followed for three months for any sign or symptom of a recurrent ischemic attack. Recurrent ischemic attacks happened in 9.4% of the patients. None of the criteria of ABCD2-F was associated with higher chance of ischemic attacks. Similarly, ABCD2-F was not different between patients with or without repeat cerebral ischemia. The addition of atrial fibrillation to ABCD2 did not enhance the accuracy of this scoring system to detect patients high risk for repeat cerebral ischemia. More studies in the future to improve sensitivity and specificity of this test are warranted. PMID:27306346

  4. Positive psychotherapy.

    PubMed

    Seligman, Martin E P; Rashid, Tayyab; Parks, Acacia C

    2006-11-01

    Positive psychotherapy (PPT) contrasts with standard interventions for depression by increasing positive emotion, engagement, and meaning rather than directly targeting depressive symptoms. The authors have tested the effects of these interventions in a variety of settings. In informal student and clinical settings, people not uncommonly reported them to be "life-changing." Delivered on the Web, positive psychology exercises relieved depressive symptoms for at least 6 months compared with placebo interventions, the effects of which lasted less than a week. In severe depression, the effects of these Web exercises were particularly striking. This address reports two preliminary studies: In the first, PPT delivered to groups significantly decreased levels of mild-to-moderate depression through 1-year follow-up. In the second, PPT delivered to individuals produced higher remission rates than did treatment as usual and treatment as usual plus medication among outpatients with major depressive disorder. Together, these studies suggest that treatments for depression may usefully be supplemented by exercises that explicitly increase positive emotion, engagement, and meaning. ((c) 2006 APA, all rights reserved). PMID:17115810

  5. Positively Adolescent!

    ERIC Educational Resources Information Center

    Williamson, Sue

    2000-01-01

    Believes that music teachers should reassess their views toward adolescent behavior in the music classroom by learning to see their behavior in a positive light. Describes teaching strategies that build on four adolescent behaviors: (1) desire for peer acceptance; (2) abundant energy; (3) love of fun; and (4) limited time-managing skills. (CMK)

  6. Host tree influences on longicorn beetle (Coleoptera: Cerambycidae) attack in subtropical Corymbia (Myrtales: Myrtaceae).

    PubMed

    Nahrung, Helen F; Smith, Timothy E; Wiegand, Aaron N; Lawson, Simon A; Debuse, Valerie J

    2014-02-01

    Phoracantha longicorn beetles are endemic to Australia, and some species have become significant pests of eucalypts worldwide, yet little is known about their host plant interactions and factors influencing tree susceptibility in Australia. Here, we investigate the host relationships of Phoracantha solida (Blackburn, 1894) on four eucalypt taxa (one pure species and three hybrid families), examining feeding site physical characteristics including phloem thickness, density, and moisture content, and host tree factors such as diameter, height, growth, taper, and survival. We also determine the cardinal and vertical (within-tree) and horizontal (between-tree) spatial distribution of borers. Fewer than 10% of P. solida attacks were recorded from the pure species (Corymbia citriodora subsp. variegate (Hook)), and this taxon also showed the highest survival, phloem thickness, relative growth rate, and bark:wood area. For the two most susceptible taxa, borer severity was negatively correlated with moisture content, and positively related to phloem density. Borers were nonrandomly and nonuniformly distributed within trees, and were statistically aggregated in 32% of plots. More attacks were situated on the northern side of the tree than the other aspects, and most larvae fed within the lower 50 cm of the bole, with attack height positively correlated with severity. Trees with borers had more dead neighbors, and more bored neighbors, than trees without borers, while within plots, borer incidence and severity were positively correlated. Because the more susceptible taxa overlapped with less susceptible taxa for several physical tree factors, the role of primary and secondary chemistries in determining host suitability needs to be investigated. Nevertheless, taxon, moisture content, phloem density, tree size, and mortality of neighboring trees appeared the most important physical characteristics influencing host suitability for P. solida at this site.

  7. Trigeminal nociceptive transmission in migraineurs predicts migraine attacks.

    PubMed

    Stankewitz, Anne; Aderjan, David; Eippert, Falk; May, Arne

    2011-02-01

    Several lines of evidence suggest a major role of the trigeminovascular system in the pathogenesis of migraine. Using functional magnetic resonance imaging (fMRI), we compared brain responses during trigeminal pain processing in migraine patients with those of healthy control subjects. The main finding is that the activity of the spinal trigeminal nuclei in response to nociceptive stimulation showed a cycling behavior over the migraine interval. Although interictal (i.e., outside of attack) migraine patients revealed lower activations in the spinal trigeminal nuclei compared with controls, preictal (i.e., shortly before attack) patients showed activity similar to controls, which demonstrates that the trigeminal activation level increases over the pain-free migraine interval. Remarkably, the distance to the next headache attack was predictable by the height of the signal intensities in the spinal nuclei. Migraine patients scanned during the acute spontaneous migraine attack showed significantly lower signal intensities in the trigeminal nuclei compared with controls, demonstrating activity levels similar to interictal patients. Additionally we found-for the first time using fMRI-that migraineurs showed a significant increase in activation of dorsal parts of the pons, previously coined "migraine generator." Unlike the dorsal pons activation usually linked to migraine attacks, the gradient-like activity following nociceptive stimulation in the spinal trigeminal neurons likely reflects a raise in susceptibility of the brain to generate the next attack, as these areas increase their activity long before headache starts. This oscillating behavior may be a key player in the generation of migraine headache, whereas attack-specific pons activations are most likely a secondary event.

  8. Attacks, applications, and evaluation of known watermarking algorithms with Checkmark

    NASA Astrophysics Data System (ADS)

    Meerwald, Peter; Pereira, Shelby

    2002-04-01

    The Checkmark benchmarking tool was introduced to provide a framework for application-oriented evaluation of watermarking schemes. In this article we introduce new attacks and applications into the existing Checkmark framework. In addition to describing new attacks and applications, we also compare the performance of some well-known watermarking algorithms (proposed by Bruyndonckx,Cox, Fridrich, Dugad, Kim, Wang, Xia, Xie, Zhu and Pereira) with respect to the Checkmark benchmark. In particular, we consider the non-geometric application which contains tests that do not change the geometry of image. This attack constraint is artificial, but yet important for research purposes since a number of algorithms may be interesting, but would score poorly with respect to specific applications simply because geometric compensation has not been incorporated. We note, however, that with the help of image registration, even research algorithms that do not have counter-measures against geometric distortion -- such as a template or reference watermark -- can be evaluated. In the first version of the Checkmark benchmarking program, application-oriented evaluation was introduced, along with many new attacks not already considered in the literature. A second goal of this paper is to introduce new attacks and new applications into the Checkmark framework. In particular, we introduce the following new applications: video frame watermarking, medical imaging and watermarking of logos. Video frame watermarking includes low compression attacks and distortions which warp the edges of the video as well as general projective transformations which may result from someone filming the screen at a cinema. With respect to medical imaging, only small distortions are considered and furthermore it is essential that no distortions are present at embedding. Finally for logos, we consider images of small sizes and particularly compression, scaling, aspect ratio and other small distortions. The challenge

  9. Activist sentenced to 25 years for attack on girl in Maryland.

    PubMed

    1999-09-17

    [Name removed] was sentenced to 25 years in prison for first-degree assault when he sexually abused a 9-year-old girl. [Name removed] received the maximum sentence because he was HIV-positive, which classified the attack as possessing proof of serious harm with the substantial risk of death. [Name removed] had been convicted for child molestation twice before this incident. He was a co-founder and president of the Frederick-based People with AIDS Committee of Maryland before his arrest. PMID:11366837

  10. Position sensor

    NASA Technical Reports Server (NTRS)

    Auer, Siegfried (Inventor)

    1988-01-01

    A radiant energy angle sensor is provided wherein the sensitive portion thereof comprises a pair of linear array detectors with each detector mounted normal to the other to provide X and Y channels and a pair of slits spaced from the pair of linear arrays with each of the slits positioned normal to its associated linear array. There is also provided electrical circuit means connected to the pair of linear array detectors and to separate X and Y axes outputs.

  11. Positive Psychologists on Positive Constructs

    ERIC Educational Resources Information Center

    Lyubomirsky, Sonja

    2012-01-01

    Comments on the original article by McNulty and Fincham (see record 2011-15476-001). In their article, the authors offered compelling evidence that constructs such as forgiveness and optimism can have both beneficial and adverse consequences, depending on the context. Their caution about labeling particular psychological processes as "positive" is…

  12. Capacity and optimal collusion attack channels for Gaussian fingerprinting games

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Moulin, Pierre

    2007-02-01

    In content fingerprinting, the same media covertext - image, video, audio, or text - is distributed to many users. A fingerprint, a mark unique to each user, is embedded into each copy of the distributed covertext. In a collusion attack, two or more users may combine their copies in an attempt to "remove" their fingerprints and forge a pirated copy. To trace the forgery back to members of the coalition, we need fingerprinting codes that can reliably identify the fingerprints of those members. Researchers have been focusing on designing or testing fingerprints for Gaussian host signals and the mean square error (MSE) distortion under some classes of collusion attacks, in terms of the detector's error probability in detecting collusion members. For example, under the assumptions of Gaussian fingerprints and Gaussian attacks (the fingerprinted signals are averaged and then the result is passed through a Gaussian test channel), Moulin and Briassouli1 derived optimal strategies in a game-theoretic framework that uses the detector's error probability as the performance measure for a binary decision problem (whether a user participates in the collusion attack or not); Stone2 and Zhao et al. 3 studied average and other non-linear collusion attacks for Gaussian-like fingerprints; Wang et al. 4 stated that the average collusion attack is the most efficient one for orthogonal fingerprints; Kiyavash and Moulin 5 derived a mathematical proof of the optimality of the average collusion attack under some assumptions. In this paper, we also consider Gaussian cover signals, the MSE distortion, and memoryless collusion attacks. We do not make any assumption about the fingerprinting codes used other than an embedding distortion constraint. Also, our only assumptions about the attack channel are an expected distortion constraint, a memoryless constraint, and a fairness constraint. That is, the colluders are allowed to use any arbitrary nonlinear strategy subject to the above

  13. Robustness of network of networks under targeted attack

    NASA Astrophysics Data System (ADS)

    Dong, Gaogao; Gao, Jianxi; Du, Ruijin; Tian, Lixin; Stanley, H. Eugene; Havlin, Shlomo

    2013-05-01

    The robustness of a network of networks (NON) under random attack has been studied recently [Gao , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.107.195701 107, 195701 (2011)]. Understanding how robust a NON is to targeted attacks is a major challenge when designing resilient infrastructures. We address here the question how the robustness of a NON is affected by targeted attack on high- or low-degree nodes. We introduce a targeted attack probability function that is dependent upon node degree and study the robustness of two types of NON under targeted attack: (i) a tree of n fully interdependent Erdős-Rényi or scale-free networks and (ii) a starlike network of n partially interdependent Erdős-Rényi networks. For any tree of n fully interdependent Erdős-Rényi networks and scale-free networks under targeted attack, we find that the network becomes significantly more vulnerable when nodes of higher degree have higher probability to fail. When the probability that a node will fail is proportional to its degree, for a NON composed of Erdős-Rényi networks we find analytical solutions for the mutual giant component P∞ as a function of p, where 1-p is the initial fraction of failed nodes in each network. We also find analytical solutions for the critical fraction pc, which causes the fragmentation of the n interdependent networks, and for the minimum average degree k¯min below which the NON will collapse even if only a single node fails. For a starlike NON of n partially interdependent Erdős-Rényi networks under targeted attack, we find the critical coupling strength qc for different n. When q>qc, the attacked system undergoes an abrupt first order type transition. When q≤qc, the system displays a smooth second order percolation transition. We also evaluate how the central network becomes more vulnerable as the number of networks with the same coupling strength q increases. The limit of q=0 represents no dependency, and the results are consistent with

  14. 3 CFR - Continuation of the National Emergency With Respect to Certain Terrorist Attacks

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... to Certain Terrorist Attacks Presidential Documents Other Presidential Documents Notice of September 10, 2010 Continuation of the National Emergency With Respect to Certain TerroristAttacks Consistent... terrorist attacks of September 11, 2001,and the continuing and immediate threat of further attacks on...

  15. 3 CFR - Continuation of the National Emergency With Respect to Certain Terrorist Attacks

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... to Certain Terrorist Attacks Presidential Documents Other Presidential Documents Notice of September 9, 2011 Continuation of the National Emergency With Respect to Certain Terrorist Attacks Consistent... terrorist attacks of September 11, 2001, and the continuing and immediate threat of further attacks on...

  16. 3 CFR - Continuation of the National Emergency With Respect to Certain Terrorist Attacks

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... to Certain Terrorist Attacks Presidential Documents Other Presidential Documents Notice of September 11, 2012 Continuation of the National Emergency With Respect to Certain Terrorist Attacks Consistent... terrorist attacks of September 11, 2001, and the continuing and immediate threat of further attacks on...

  17. 3 CFR - Continuation of the National Emergency With Respect to Certain Terrorist Attacks

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... to Certain Terrorist Attacks Presidential Documents Other Presidential Documents Notice of September 10, 2013 Continuation of the National Emergency With Respect to Certain Terrorist Attacks Consistent... terrorist attacks of September 11, 2001, and the continuing and immediate threat of further attacks on...

  18. Learn What a Heart Attack Feels Like--It Could Save Your Life

    MedlinePlus

    Learn What a Heart Attack Feels Like— It Could Save Your Life. This fact sheet tells you about heart attack signs. It also tells you what to do ... your life. 1. Know the signs of a heart attack. 2. Understand that heart attacks are not all ...

  19. Impact of Degree Heterogeneity on Attack Vulnerability of Interdependent Networks

    PubMed Central

    Sun, Shiwen; Wu, Yafang; Ma, Yilin; Wang, Li; Gao, Zhongke; Xia, Chengyi

    2016-01-01

    The study of interdependent networks has become a new research focus in recent years. We focus on one fundamental property of interdependent networks: vulnerability. Previous studies mainly focused on the impact of topological properties upon interdependent networks under random attacks, the effect of degree heterogeneity on structural vulnerability of interdependent networks under intentional attacks, however, is still unexplored. In order to deeply understand the role of degree distribution and in particular degree heterogeneity, we construct an interdependent system model which consists of two networks whose extent of degree heterogeneity can be controlled simultaneously by a tuning parameter. Meanwhile, a new quantity, which can better measure the performance of interdependent networks after attack, is proposed. Numerical simulation results demonstrate that degree heterogeneity can significantly increase the vulnerability of both single and interdependent networks. Moreover, it is found that interdependent links between two networks make the entire system much more fragile to attacks. Enhancing coupling strength between networks can greatly increase the fragility of both networks against targeted attacks, which is most evident under the case of max-max assortative coupling. Current results can help to deepen the understanding of structural complexity of complex real-world systems. PMID:27609483

  20. Deterring watermark collusion attacks using signal processing techniques

    NASA Astrophysics Data System (ADS)

    Lemma, Aweke N.; van der Veen, Michiel

    2007-02-01

    Collusion attack is a malicious watermark removal attack in which the hacker has access to multiple copies of the same content with different watermarks and tries to remove the watermark using averaging. In the literature, several solutions to collusion attacks have been reported. The main stream solutions aim at designing watermark codes that are inherently resistant to collusion attacks. The other approaches propose signal processing based solutions that aim at modifying the watermarked signals in such a way that averaging multiple copies of the content leads to a significant degradation of the content quality. In this paper, we present signal processing based technique that may be deployed for deterring collusion attacks. We formulate the problem in the context of electronic music distribution where the content is generally available in the compressed domain. Thus, we first extend the collusion resistance principles to bit stream signals and secondly present experimental based analysis to estimate a bound on the maximum number of modified versions of a content that satisfy good perceptibility requirement on one hand and destructive averaging property on the other hand.

  1. Learning from history: The Glasgow Airport terrorist attack.

    PubMed

    Crichton, Gillies

    Glasgow Airport was the target of a terrorist attack on 30th June, 2007. Many people within Scotland had come to believe that Scotland was immune from terrorism. This perception was in large part informed by Scotland's experience during the protracted Troubles in Northern Ireland, during which the Provisional Irish Republican Army's mainland bombing campaign focused on targets in England, sparing both Scotland and Wales. While Glasgow Airport did not expect such an attack to take place, meticulous planning, organising and testing of plans had taken place to mitigate the unlikely event of such an attack. The attack stands up as a shining example of robust business continuity management, where the airport reopened for business as usual in less than 24 hours from the time of the attack. Little is known about how the airport handled the situation in conjunction with other responding agencies as people tend to want to focus on high-profile disasters only. Yet countless such incidents are happening worldwide on a daily basis, in which there are excellent learning opportunities, and, taken in the spirit of converting hindsight into foresight, the likelihood of similar incidents could potentially be reduced in the future.

  2. Myocardial perfusion imaging study of CO(2)-induced panic attack.

    PubMed

    Soares-Filho, Gastão L F; Machado, Sergio; Arias-Carrión, Oscar; Santulli, Gaetano; Mesquita, Claudio T; Cosci, Fiammetta; Silva, Adriana C; Nardi, Antonio E

    2014-01-15

    Chest pain is often seen alongside with panic attacks. Moreover, panic disorder has been suggested as a risk factor for cardiovascular disease and even a trigger for acute coronary syndrome. Patients with coronary artery disease may have myocardial ischemia in response to mental stress, in which panic attack is a strong component, by an increase in coronary vasomotor tone or sympathetic hyperactivity setting off an increase in myocardial oxygen consumption. Indeed, coronary artery spasm was presumed to be present in cases of cardiac ischemia linked to panic disorder. These findings correlating panic disorder with coronary artery disease lead us to raise questions about the favorable prognosis of chest pain in panic attack. To investigate whether myocardial ischemia is the genesis of chest pain in panic attacks, we developed a myocardial perfusion study through research by myocardial scintigraphy in patients with panic attacks induced in the laboratory by inhalation of 35% carbon dioxide. In conclusion, from the data obtained, some hypotheses are discussed from the viewpoint of endothelial dysfunction and microvascular disease present in mental stress response. PMID:24188891

  3. Gait biometrics under spoofing attacks: an experimental investigation

    NASA Astrophysics Data System (ADS)

    Hadid, Abdenour; Ghahramani, Mohammad; Kellokumpu, Vili; Feng, Xiaoyi; Bustard, John; Nixon, Mark

    2015-11-01

    Gait is a relatively biometric modality which has a precious advantage over other modalities, such as iris and voice, in that it can be easily captured from a distance. Although it has recently become a topic of great interest in biometric research, there has been little investigation into gait spoofing attacks where a person tries to imitate the clothing or walking style of someone else. We recently analyzed for the first time the effects of spoofing attacks on silhouette-based gait biometric systems and showed that it was indeed possible to spoof gait biometric systems by clothing impersonation and the deliberate selection of a target that has a similar build to the attacker. To gain deeper insight into the performance of current gait biometric systems under spoofing attacks, we provide a thorough investigation on how clothing can be used to spoof a target and evaluate the performance of two state-of-the-art recognition methods on a gait spoofing database recorded at the University of Southampton. Furthermore, we describe and evaluate an initial solution coping with gait spoofing attacks. The obtained results are very promising and point out interesting findings which can be used for future investigations.

  4. Vulnerability of complex networks under three-level-tree attacks

    NASA Astrophysics Data System (ADS)

    Hao, Yao-hui; Han, Ji-hong; Lin, Yi; Liu, Lin

    2016-11-01

    We investigate vulnerability of complex networks including model networks and real world networks subject to three-level-tree attack. Specifically, we remove three different three-level-tree structures: RRN (Random Root Node), MaxDRN (Max Degree Root Node) and MinDRN (Min Degree Root Node) from a network iteratively until there is no three-level-tree left. Results demonstrate that random network is more robust than scale-free network against three tree attacks, and the robustness of random network decreases as the < k > increases. And scale-free network shows different characteristics in different tree attack modes. The robustness of scale-free is not affected by the < k > parameters for RRN, but increases as the < k > increases for MinDRN. The important thing is that MaxDRN is the most effective in the three tree attack modes, especially for scale-free network. These findings supplement and extend the previous attack results on nodes and edges, and can thus help us better explain the vulnerability of different networks, and provide an insight into more tolerant real complex systems design.

  5. Impact of Degree Heterogeneity on Attack Vulnerability of Interdependent Networks

    NASA Astrophysics Data System (ADS)

    Sun, Shiwen; Wu, Yafang; Ma, Yilin; Wang, Li; Gao, Zhongke; Xia, Chengyi

    2016-09-01

    The study of interdependent networks has become a new research focus in recent years. We focus on one fundamental property of interdependent networks: vulnerability. Previous studies mainly focused on the impact of topological properties upon interdependent networks under random attacks, the effect of degree heterogeneity on structural vulnerability of interdependent networks under intentional attacks, however, is still unexplored. In order to deeply understand the role of degree distribution and in particular degree heterogeneity, we construct an interdependent system model which consists of two networks whose extent of degree heterogeneity can be controlled simultaneously by a tuning parameter. Meanwhile, a new quantity, which can better measure the performance of interdependent networks after attack, is proposed. Numerical simulation results demonstrate that degree heterogeneity can significantly increase the vulnerability of both single and interdependent networks. Moreover, it is found that interdependent links between two networks make the entire system much more fragile to attacks. Enhancing coupling strength between networks can greatly increase the fragility of both networks against targeted attacks, which is most evident under the case of max-max assortative coupling. Current results can help to deepen the understanding of structural complexity of complex real-world systems.

  6. Automatic analysis of attack data from distributed honeypot network

    NASA Astrophysics Data System (ADS)

    Safarik, Jakub; Voznak, MIroslav; Rezac, Filip; Partila, Pavol; Tomala, Karel

    2013-05-01

    There are many ways of getting real data about malicious activity in a network. One of them relies on masquerading monitoring servers as a production one. These servers are called honeypots and data about attacks on them brings us valuable information about actual attacks and techniques used by hackers. The article describes distributed topology of honeypots, which was developed with a strong orientation on monitoring of IP telephony traffic. IP telephony servers can be easily exposed to various types of attacks, and without protection, this situation can lead to loss of money and other unpleasant consequences. Using a distributed topology with honeypots placed in different geological locations and networks provides more valuable and independent results. With automatic system of gathering information from all honeypots, it is possible to work with all information on one centralized point. Communication between honeypots and centralized data store use secure SSH tunnels and server communicates only with authorized honeypots. The centralized server also automatically analyses data from each honeypot. Results of this analysis and also other statistical data about malicious activity are simply accessible through a built-in web server. All statistical and analysis reports serve as information basis for an algorithm which classifies different types of used VoIP attacks. The web interface then brings a tool for quick comparison and evaluation of actual attacks in all monitored networks. The article describes both, the honeypots nodes in distributed architecture, which monitor suspicious activity, and also methods and algorithms used on the server side for analysis of gathered data.

  7. QTc dispersion and P-wave dispersion during migraine attacks.

    PubMed

    Duru, M; Melek, I; Seyfeli, E; Duman, T; Kuvandik, G; Kaya, H; Yalçin, F

    2006-06-01

    The aim of this study was to investigate increase of QTc dispersion and P-wave dispersion during migraine attacks. Fifty-five patients (16-65 years of age, 49 women, six men) with migraine were included in our study. Heart rate, QTc interval, maximum and minimum QTc interval, QTc dispersion, maximum and minimum P-wave duration and P-wave dispersion were measured from 12-lead ECG recording during migraine attacks and pain-free periods. ECGs were transferred to a personal computer via a scanner and then used for magnification of x400 by Adobe Photoshop software. Maximum QTc interval (454 +/- 24 ms vs. 429 +/- 23 ms, P < 0.001), QTc interval (443 +/- 26 ms vs. 408 +/- 22 ms, P < 0.001) and QTc dispersion (63 +/- 18 ms vs. 43 +/- 14 ms, P < 0.001) were found significantly higher during migraine attacks compared with pain-free periods. Maximum P-wave duration (107 +/- 11 ms vs. 100 +/- 11 ms, P < 0.001) and P-wave dispersion (45 +/- 13 ms vs. 35 +/- 13 ms, P < 0.001) were found higher during migraine attacks than pain-free periods. We concluded that migraine attacks are associated with increased QTc and P-wave dispersion compared with pain-free periods.

  8. Impact of Degree Heterogeneity on Attack Vulnerability of Interdependent Networks.

    PubMed

    Sun, Shiwen; Wu, Yafang; Ma, Yilin; Wang, Li; Gao, Zhongke; Xia, Chengyi

    2016-09-09

    The study of interdependent networks has become a new research focus in recent years. We focus on one fundamental property of interdependent networks: vulnerability. Previous studies mainly focused on the impact of topological properties upon interdependent networks under random attacks, the effect of degree heterogeneity on structural vulnerability of interdependent networks under intentional attacks, however, is still unexplored. In order to deeply understand the role of degree distribution and in particular degree heterogeneity, we construct an interdependent system model which consists of two networks whose extent of degree heterogeneity can be controlled simultaneously by a tuning parameter. Meanwhile, a new quantity, which can better measure the performance of interdependent networks after attack, is proposed. Numerical simulation results demonstrate that degree heterogeneity can significantly increase the vulnerability of both single and interdependent networks. Moreover, it is found that interdependent links between two networks make the entire system much more fragile to attacks. Enhancing coupling strength between networks can greatly increase the fragility of both networks against targeted attacks, which is most evident under the case of max-max assortative coupling. Current results can help to deepen the understanding of structural complexity of complex real-world systems.

  9. Learning from history: The Glasgow Airport terrorist attack.

    PubMed

    Crichton, Gillies

    Glasgow Airport was the target of a terrorist attack on 30th June, 2007. Many people within Scotland had come to believe that Scotland was immune from terrorism. This perception was in large part informed by Scotland's experience during the protracted Troubles in Northern Ireland, during which the Provisional Irish Republican Army's mainland bombing campaign focused on targets in England, sparing both Scotland and Wales. While Glasgow Airport did not expect such an attack to take place, meticulous planning, organising and testing of plans had taken place to mitigate the unlikely event of such an attack. The attack stands up as a shining example of robust business continuity management, where the airport reopened for business as usual in less than 24 hours from the time of the attack. Little is known about how the airport handled the situation in conjunction with other responding agencies as people tend to want to focus on high-profile disasters only. Yet countless such incidents are happening worldwide on a daily basis, in which there are excellent learning opportunities, and, taken in the spirit of converting hindsight into foresight, the likelihood of similar incidents could potentially be reduced in the future. PMID:25416378

  10. Pharmacokinetics of rizatriptan tablets during and between migraine attacks.

    PubMed

    Cutler, N R; Jhee, S S; Majumdar, A K; McLaughlin, D; Brucker, M J; Carides, A D; Kramer, M S; Matzura-Wolfe, D; Reines, S A; Goldberg, M R

    1999-04-01

    Gastric stasis during migraine attacks results in delayed absorption of several orally administered antimigraine agents. This study, as part of a larger trial, was conducted to examine the pharmacokinetics of rizatriptan tablets during and between migraine attacks. Participating patients met IHS criteria for migraine with or without aura, and suffered between one and eight migraines per month for the previous 6 months. In part 1 of the study, 21 patients were randomized to receive a single 5-mg tablet of rizatriptan or placebo in the migraine-free state. In part 2, the same patients were treated during migraine with rizatriptan 5-mg tablets (n=18) or placebo (n=3). Blood samples were obtained before dosing and 0.25, 0.5, 0.75, 1, 1.5, 2, 3, 4, 6, 8, and 12 hours after dosing. The plasma concentration profile (ie, AUC((0-infinity)), C(max), T(max)) of rizatriptan 5-mg tablets administered during and between migraine attacks were comparable. The median T(max) for rizatriptan between and during attacks was 1 hour, indicating rapid absorption even during a migraine attack. Rizatriptan 5 mg was well tolerated and 67% of the patients experienced headache relief 2 hours postdose. PMID:15613223

  11. Impact of Degree Heterogeneity on Attack Vulnerability of Interdependent Networks.

    PubMed

    Sun, Shiwen; Wu, Yafang; Ma, Yilin; Wang, Li; Gao, Zhongke; Xia, Chengyi

    2016-01-01

    The study of interdependent networks has become a new research focus in recent years. We focus on one fundamental property of interdependent networks: vulnerability. Previous studies mainly focused on the impact of topological properties upon interdependent networks under random attacks, the effect of degree heterogeneity on structural vulnerability of interdependent networks under intentional attacks, however, is still unexplored. In order to deeply understand the role of degree distribution and in particular degree heterogeneity, we construct an interdependent system model which consists of two networks whose extent of degree heterogeneity can be controlled simultaneously by a tuning parameter. Meanwhile, a new quantity, which can better measure the performance of interdependent networks after attack, is proposed. Numerical simulation results demonstrate that degree heterogeneity can significantly increase the vulnerability of both single and interdependent networks. Moreover, it is found that interdependent links between two networks make the entire system much more fragile to attacks. Enhancing coupling strength between networks can greatly increase the fragility of both networks against targeted attacks, which is most evident under the case of max-max assortative coupling. Current results can help to deepen the understanding of structural complexity of complex real-world systems. PMID:27609483

  12. RFID Distance Bounding Protocol with Mixed Challenges to Prevent Relay Attacks

    NASA Astrophysics Data System (ADS)

    Kim, Chong Hee; Avoine, Gildas

    RFID systems suffer from different location-based attacks such as distance fraud, mafia fraud and terrorist fraud attacks. Among them mafia fraud attack is the most serious since this attack can be mounted without the notice of both the reader and the tag. An adversary performs a kind of man-in-the-middle attack between the reader and the tag. It is very difficult to prevent this attack since the adversary does not change any data between the reader and the tag. Recently distance bounding protocols measuring the round-trip time between the reader and the tag have been researched to prevent this attack.

  13. Positioning apparatus

    DOEpatents

    Vogel, M.A.; Alter, P.

    1983-07-07

    An apparatus is provided for precisely adjusting the position of an article relative to a beam emerging from a neutron source disposed in a housing. The apparatus includes a support pivotably mounted on a movable base plate and freely suspended therefrom. The support is gravity biased toward the housing and carries an article holder movable in a first direction longitudinally of the axis of said beam and normally urged into engagement against said housing. Means are provided for moving the base plate in two directions to effect movement of the suspended holder in two mutually perpendicular directions, respectively, normal to the axis of the beam.

  14. Positioning apparatus

    DOEpatents

    Vogel, Max A.; Alter, Paul

    1986-05-06

    An apparatus for precisely positioning materials test specimens within the optimum neutron flux path emerging from a neutron source located in a housing. The test specimens are retained in a holder mounted on the free end of a support pivotably mounted and suspended from a movable base plate. The support is gravity biased to urge the holder in a direction longitudinally of the flux path against the housing. Means are provided for moving the base plate in two directions to effect movement of the holder in two mutually perpendicular directions normal to the axis of the flux path.

  15. Positioning apparatus

    DOEpatents

    Vogel, Max A.; Alter, Paul

    1986-01-01

    An apparatus for precisely positioning materials test specimens within the optimum neutron flux path emerging from a neutron source located in a housing. The test specimens are retained in a holder mounted on the free end of a support pivotably mounted and suspended from a movable base plate. The support is gravity biased to urge the holder in a direction longitudinally of the flux path against the housing. Means are provided for moving the base plate in two directions to effect movement of the holder in two mutually perpendicular directions normal to the axis of the flux path.

  16. POSITIONING DEVICE

    DOEpatents

    Wall, R.R.; Peterson, D.L.

    1959-09-15

    A positioner is described for a vertical reactor-control rod. The positioner comprises four grooved friction rotatable members that engage the control rod on all sides and shift it longitudinally. The four friction members are drivingly interconnected for conjoint rotation and comprise two pairs of coaxial members. The members of each pair are urged toward one another by hydraulic or pneumatic pressure and thus grip the control rod so as to hold it in any position or adjust it. Release of the by-draulic or pneumatic pressure permits springs between the friction members of each pair to force them apart, whereby the control rod moves quickly by gravity into the reactor.

  17. Gray Matter Is Targeted in First-Attack Multiple Sclerosis

    SciTech Connect

    Schutzer, Steven E.; Angel, Thomas E.; Liu, Tao; Schepmoes, Athena A.; Xie, Fang; Bergquist, Jonas P.; Vecsei, Lazlo'; Zadori, Denes; Camp, David G.; Holland, Bart K.; Smith, Richard D.; Coyle, Patricia K.

    2013-09-10

    The cause of multiple sclerosis (MS), its driving pathogenesis at the earliest stages, and what factors allow the first clinical attack to manifest remain unknown. Some imaging studies suggest gray rather than white matter may be involved early, and some postulate this may be predictive of developing MS. Other imaging studies are in conflict. To determine if there was objective molecular evidence of gray matter involvement in early MS we used high-resolution mass spectrometry to identify proteins in the cerebrospinal fluid (CSF) of first-attack MS patients (two independent groups) compared to established relapsing remitting (RR) MS and controls. We found that the CSF proteins in first-attack patients were differentially enriched for gray matter components (axon, neuron, synapse). Myelin components did not distinguish these groups. The results support that gray matter dysfunction is involved early in MS, and also may be integral for the initial clinical presentation.

  18. Acute kidney injury after massive attack of Africanised bees

    PubMed Central

    Bridi, Ramaiane A; Balbi, Andre Luis; Neves, Precil M; Ponce, Daniela

    2014-01-01

    Acute kidney injury (AKI) is a well-documented complication of massive attack by Africanised bees and can be observed 48–72 h after the accident. We report a case of Africanised bees attack followed by severe and lethal AKI. A 56-year-old man was admitted to emergency department after a massive attack of Africanised bees (>1000 bee stings). He was unconscious, presenting with hypotension and tachycardia. Mechanical ventilation, volume expansion and care for anaphylaxis were instituted. The patient was transferred to the intensive care unit (ICU) and after 48 h he developed rhabdomyolysis, oliguria, increased creatinine levels, hyperkalaemia and refractory acidosis. A diagnosis of AKI secondary to rhabdomyolysis and shock was made. The patient was treated with a prolonged course of haemodialysis. However, he progressed to refractory shock and died 5 days after admission. PMID:24618864

  19. Conservation biology: lion attacks on humans in Tanzania.

    PubMed

    Packer, Craig; Ikanda, Dennis; Kissui, Bernard; Kushnir, Hadas

    2005-08-18

    Large carnivores inspire opposition to conservation efforts owing to their impact on livestock and human safety. Here we analyse the pattern of lion attacks over the past 15 years on humans in Tanzania, which has the largest population of lions in Africa, and find that they have killed more than 563 Tanzanians since 1990 and injured at least 308. Attacks have increased dramatically during this time: they peak at harvest time each year and are most frequent in areas with few prey apart from bush pigs (Potamochoerus larvatus), the most common nocturnal crop pest. Our findings provide an important starting point for devising strategies to reduce the risk to rural Tanzanians of lion attacks.

  20. Effects of dopamine agonists on hypothalamic defensive attack in cats.

    PubMed

    Maeda, H; Sato, T; Maki, S

    1985-07-01

    The effects of methamphetamine (MAT) and apomorphine (APO), dopamine agonists, were studied in 16 cats to evaluate their effects on threshold for defensive attack behavior elicited by electrical stimulation of the ventromedial hypothalamic nucleus (VMH). Directed attack and hissing were selected from elementary responses as constituting a defensive attack. Hissing threshold was measured in two situations, one with human provocation and the other without provocation. MAT administered systemically lowered the thresholds for all three types of responses in a dose-related manner (0.5, 1.0, and 3.0 mg/kg). The effects of 1.0 mg/kg of APO were almost identical to those observed with 0.5 or 1.0 mg/kg of MAT. These results suggest that MAT-induced aggressive behavior may be mediated by a dopamine-induced increase in the excitability of the VMH. PMID:4059404

  1. A Model of Biological Attacks on a Realistic Population

    NASA Astrophysics Data System (ADS)

    Carley, Kathleen M.; Fridsma, Douglas; Casman, Elizabeth; Altman, Neal; Chen, Li-Chiou; Kaminsky, Boris; Nave, Demian; Yahja, Alex

    The capability to assess the impacts of large-scale biological attacks and the efficacy of containment policies is critical and requires knowledge-intensive reasoning about social response and disease transmission within a complex social system. There is a close linkage among social networks, transportation networks, disease spread, and early detection. Spatial dimensions related to public gathering places such as hospitals, nursing homes, and restaurants, can play a major role in epidemics [Klovdahl et. al. 2001]. Like natural epidemics, bioterrorist attacks unfold within spatially defined, complex social systems, and the societal and networked response can have profound effects on their outcome. This paper focuses on bioterrorist attacks, but the model has been applied to emergent and familiar diseases as well.

  2. No link between OC use and heart attack.

    PubMed

    1999-10-01

    A retrospective study conducted in England, Scotland, and Wales concluded that there is no significant increase in the risk of acute myocardial infarction (AMI/heart attack) in women who use modern low-estrogen dose oral contraceptives (OCs). The study matched 448 women aged 16-44 years who had suffered a heart attack with 1728 women in the control group. The leader of the study stated that women should be warned of the classical risk factors for AMI, particularly smoking, and not the OC that they are taking. Furthermore, researchers in the UK study revealed that of the women under age 45 years who suffered a heart attack, 87% were not taking an OC. Moreover, majority of these women had at least one or more known cardiovascular risk factors. In addition, the older studies clarified that the increase in risk for thrombotic diseases, including AMI, is applicable primarily to older high-dose OCs.

  3. A case of hereditary angioedema involving recurrent abdominal attacks.

    PubMed

    Kasamatsu, Yoshihiro; Yoshinoya, Kiyokazu; Kasamatsu, Yu; Yamamoto, Tetsuro; Horiuchi, Takahiko; Kadoya, Masatoshi

    2011-01-01

    A 44-year-old Japanese woman was diagnosed with type 1 hereditary angioedema (HAE) at the age of 30. In March 2007, she began suffering from severe abdominal pain due to intestinal edema. After treatment with C1-INH concentrate, her symptoms disappeared. However, during the subsequent three years, the frequency of the attacks increased continuously, and C1-INH concentrate was necessary for treatment of every attack. The increase in the number of attacks might have been due to the frequent injection of C1-INH concentrate or the deterioration of her disease course. In a genetic investigation, the patient was found to have a novel mutation in the C1-INH gene. PMID:22129507

  4. Is adiponectin a risk factor for transient ischaemic attacks?

    PubMed

    Sener, Ufuk; Uludag, Irem Fatma; Kose, Sukran; Ozcelik, Murat; Zorlu, Yasar

    2015-01-01

    Adiponectin is an adipocytokine, and it plays a role in atherosclerosis. The role of adiponectin in the development of ischaemic stroke is controversial. Up to now, adiponectin was not evaluated in transient ischaemic stroke. In this study, we investigated the relationship between adiponectin and transient ischaemic attack. Forty patients with transient ischaemic attack were included into the study. In all patients, traditional risk factors of ischaemic stroke and intima-media thickness of carotid arteries were determined. Also, the relationship between these parameters and adiponectin levels were examined. No difference was found in terms of adiponectin levels between patients and healthy subjects. In addition, there was no association between adiponectin levels and traditional risk factors. Our results suggest that adiponectin may not be a predictive risk factor of transient ischaemic attack.

  5. Ultrasonic anemometer angle of attack errors under turbulent conditions

    NASA Astrophysics Data System (ADS)

    Nakai, T.

    2009-12-01

    Measurements of eddy fluxes are premised on the assumption that wind speeds are measured accurately by an ultrasonic anemometer. Recently, ultrasonic anemometers have been shown to suffer errors depending on the angle of attack, which is the angle between the wind vector and the horizontal. The correction of these errors resulted in general increases in eddy fluxes. However, since the check of the angle of attack dependent error was carried out in the wind tunnel experiment, which would be under the condition of nearly laminar flow, the applicability of this correction to the field data under turbulent conditions has been questioned. In this study, angle of attack dependencies of wind speeds measured by Gill Windmaster ultrasonic anemometers were assessed by field experiment over meadow, considered to be turbulent conditions. By using five identical anemometers, two pairs of systems were prepared: two anemometers for references and one between them for tilt. The dependencies of (co)sine responses of anemometers on angles of attack of 0 to -90 degrees in 10-degree steps and 45 degrees were checked, and clarified that the angle of attack dependent errors occur also under turbulent conditions, with results similar to the wind tunnel experiments. Sine responses of vertical wind speeds depended not only on vertical angle of attack but also on horizontal wind direction, which had not been considered in previous studies. For more robust correction, alternative calibration functions were obtained empirically so as to reasonably explain our field experimental results. Applying this new correction, eddy fluxes increased substantially even over meadow, which is somewhat aerodynamically smooth compared with forests or agricultural fields.

  6. Assessing Terrorist Motivations for Attacking Critical "Chemical" Infrastructure

    SciTech Connect

    Ackerman, G; Bale, J; Moran, K

    2004-12-14

    Certain types of infrastructure--critical infrastructure (CI)--play vital roles in underpinning our economy, security, and way of life. One particular type of CI--that relating to chemicals--constitutes both an important element of our nation's infrastructure and a particularly attractive set of potential targets. This is primarily because of the large quantities of toxic industrial chemicals (TICs) it employs in various operations and because of the essential economic functions it serves. This study attempts to minimize some of the ambiguities that presently impede chemical infrastructure threat assessments by providing new insight into the key motivational factors that affect terrorist organizations propensity to attack chemical facilities. Prepared as a companion piece to the Center for Nonproliferation Studies August 2004 study--''Assessing Terrorist Motivations for Attacking Critical Infrastructure''--it investigates three overarching research questions: (1) why do terrorists choose to attack chemical-related infrastructure over other targets; (2) what specific factors influence their target selection decisions concerning chemical facilities; and (3) which, if any, types of groups are most inclined to attack chemical infrastructure targets? The study involved a multi-pronged research design, which made use of four discrete investigative techniques to answer the above questions as comprehensively as possible. These include: (1) a review of terrorism and threat assessment literature to glean expert consensus regarding terrorist interest in targeting chemical facilities; (2) the preparation of case studies to help identify internal group factors and contextual influences that have played a significant role in leading some terrorist groups to attack chemical facilities; (3) an examination of data from the Critical Infrastructure Terrorist Incident Catalog (CrITIC) to further illuminate the nature of terrorist attacks against chemical facilities to date; and (4

  7. Response of Rhesus Macaques (Macaca mulatta) to the Body of a Group Member That Died from a Fatal Attack

    PubMed Central

    Buhl, Jacqueline S.; Aure, Bonn; Ruiz-Lambides, Angelina; Gonzalez-Martinez, Janis; Platt, Michael L.; Brent, Lauren J. N.

    2013-01-01

    Among animals that form social bonds, the death of a conspecific may be a significant social event, representing the loss of an ally and resulting in disruptions to the dominance hierarchy. Despite this potential biological importance, we have only limited knowledge of animals' reactions to the death of a group member. This is particularly true of responses to dead adults, as most reports describe the responses of mothers to dead infants. Here, we describe in detail and provide video evidence of the behavioral responses of a group of free-ranging rhesus macaques (Macaca mulatta) immediately after the death of a mid-ranking adult male as a result of a fatal attack. High-ranking male members of the group, suspected to have carried out the attack, dragged and bit the dead body, exhibiting a rate of aggression 20 times greater than baseline levels. Lower-ranking individuals approached and inspected the body by looking closely, smelling, and grooming the fur. There was inconclusive evidence that these rhesus macaques found the death of a conspecific stressful: Levels of grooming between group members after the fatal attack were significantly higher than baseline levels, and higher than levels of grooming after nonfatal attacks. However, when grooming levels were adjusted based on the assumption that individuals positioned close to the body, i.e., those visible to researchers, were more likely to be engaged in grooming than those positioned farther away, this difference from baseline was no longer significant. The rate of self-directed behaviors after the fatal attack was also not different from baseline. Many of the behaviors we observed directed toward the body (aggression, inspection) have been previously reported in chimpanzees and geladas, and are similar to reactions sometimes displayed by humans. As such, this report represents a potentially valuable contribution the nascent field of nonhuman primate thanatology. PMID:23459587

  8. Response of Rhesus Macaques (Macaca mulatta) to the Body of a Group Member That Died from a Fatal Attack.

    PubMed

    Buhl, Jacqueline S; Aure, Bonn; Ruiz-Lambides, Angelina; Gonzalez-Martinez, Janis; Platt, Michael L; Brent, Lauren J N

    2012-08-01

    Among animals that form social bonds, the death of a conspecific may be a significant social event, representing the loss of an ally and resulting in disruptions to the dominance hierarchy. Despite this potential biological importance, we have only limited knowledge of animals' reactions to the death of a group member. This is particularly true of responses to dead adults, as most reports describe the responses of mothers to dead infants. Here, we describe in detail and provide video evidence of the behavioral responses of a group of free-ranging rhesus macaques (Macaca mulatta) immediately after the death of a mid-ranking adult male as a result of a fatal attack. High-ranking male members of the group, suspected to have carried out the attack, dragged and bit the dead body, exhibiting a rate of aggression 20 times greater than baseline levels. Lower-ranking individuals approached and inspected the body by looking closely, smelling, and grooming the fur. There was inconclusive evidence that these rhesus macaques found the death of a conspecific stressful: Levels of grooming between group members after the fatal attack were significantly higher than baseline levels, and higher than levels of grooming after nonfatal attacks. However, when grooming levels were adjusted based on the assumption that individuals positioned close to the body, i.e., those visible to researchers, were more likely to be engaged in grooming than those positioned farther away, this difference from baseline was no longer significant. The rate of self-directed behaviors after the fatal attack was also not different from baseline. Many of the behaviors we observed directed toward the body (aggression, inspection) have been previously reported in chimpanzees and geladas, and are similar to reactions sometimes displayed by humans. As such, this report represents a potentially valuable contribution the nascent field of nonhuman primate thanatology. PMID:23459587

  9. Response of Rhesus Macaques (Macaca mulatta) to the Body of a Group Member That Died from a Fatal Attack.

    PubMed

    Buhl, Jacqueline S; Aure, Bonn; Ruiz-Lambides, Angelina; Gonzalez-Martinez, Janis; Platt, Michael L; Brent, Lauren J N

    2012-08-01

    Among animals that form social bonds, the death of a conspecific may be a significant social event, representing the loss of an ally and resulting in disruptions to the dominance hierarchy. Despite this potential biological importance, we have only limited knowledge of animals' reactions to the death of a group member. This is particularly true of responses to dead adults, as most reports describe the responses of mothers to dead infants. Here, we describe in detail and provide video evidence of the behavioral responses of a group of free-ranging rhesus macaques (Macaca mulatta) immediately after the death of a mid-ranking adult male as a result of a fatal attack. High-ranking male members of the group, suspected to have carried out the attack, dragged and bit the dead body, exhibiting a rate of aggression 20 times greater than baseline levels. Lower-ranking individuals approached and inspected the body by looking closely, smelling, and grooming the fur. There was inconclusive evidence that these rhesus macaques found the death of a conspecific stressful: Levels of grooming between group members after the fatal attack were significantly higher than baseline levels, and higher than levels of grooming after nonfatal attacks. However, when grooming levels were adjusted based on the assumption that individuals positioned close to the body, i.e., those visible to researchers, were more likely to be engaged in grooming than those positioned farther away, this difference from baseline was no longer significant. The rate of self-directed behaviors after the fatal attack was also not different from baseline. Many of the behaviors we observed directed toward the body (aggression, inspection) have been previously reported in chimpanzees and geladas, and are similar to reactions sometimes displayed by humans. As such, this report represents a potentially valuable contribution the nascent field of nonhuman primate thanatology.

  10. A data fusion approach to indications and warnings of terrorist attacks

    NASA Astrophysics Data System (ADS)

    McDaniel, David; Schaefer, Gregory

    2014-05-01

    Indications and Warning (I&W) of terrorist attacks, particularly IED attacks, require detection of networks of agents and patterns of behavior. Social Network Analysis tries to detect a network; activity analysis tries to detect anomalous activities. This work builds on both to detect elements of an activity model of terrorist attack activity - the agents, resources, networks, and behaviors. The activity model is expressed as RDF triples statements where the tuple positions are elements or subsets of a formal ontology for activity models. The advantage of a model is that elements are interdependent and evidence for or against one will influence others so that there is a multiplier effect. The advantage of the formality is that detection could occur hierarchically, that is, at different levels of abstraction. The model matching is expressed as a likelihood ratio between input text and the model triples. The likelihood ratio is designed to be analogous to track correlation likelihood ratios common in JDL fusion level 1. This required development of a semantic distance metric for positive and null hypotheses as well as for complex objects. The metric uses the Web 1Terabype database of one to five gram frequencies for priors. This size requires the use of big data technologies so a Hadoop cluster is used in conjunction with OpenNLP natural language and Mahout clustering software. Distributed data fusion Map Reduce jobs distribute parts of the data fusion problem to the Hadoop nodes. For the purposes of this initial testing, open source models and text inputs of similar complexity to terrorist events were used as surrogates for the intended counter-terrorist application.

  11. Grievous Temporal and Occipital Injury Caused by a Bear Attack

    PubMed Central

    Thada, Nikhil Dinaker; Rao, Pallavi; Thada, Smitha Rani; Prasad, Kishore Chandra

    2013-01-01

    Bear attacks are reported from nearly every part of the world. The chance of a human encountering a bear increases as the remote bear territory diminishes. The sloth bear is one of the three species of bears found in India, which inhabits the forests of India and its neighboring countries. Here we describe a teenager who came to us with a critical injury involving the face, temporal and occipital bones inflicted by a sloth bear attack. He underwent a temporal exploration, facial nerve decompression, pinna reconstruction, and occipital bone repair to save him from fatality. PMID:24396623

  12. Fingerprinting Codes for Multimedia Data against Averaging Attack

    NASA Astrophysics Data System (ADS)

    Yagi, Hideki; Matsushima, Toshiyasu; Hirasawa, Shigeichi

    Code construction for digital fingerprinting, which is a copyright protection technique for multimedia, is considered. Digital fingerprinting should deter collusion attacks, where several fingerprinted copies of the same content are mixed to disturb their fingerprints. In this paper, we consider the averaging attack, which is known to be effective for multimedia fingerprinting with the spread spectrum technique. We propose new methods for constructing fingerprinting codes to increase the coding rate of conventional fingerprinting codes, while they guarantee to identify the same number of colluders. Due to the new fingerprinting codes, the system can deal with a larger number of users to supply digital contents.

  13. Burton Award Talk: Science Under Attack: Intelligent Design

    NASA Astrophysics Data System (ADS)

    Krauss, Lawrence

    2005-04-01

    Science is under attack in many places throughout our society, from the White House to the classroom. I will concentrate my remarks here on the emerging threat to science education associated with the effort to have Intelligent Design incorporated into high school science curricula. While this may appear to be primarily an attack on evolutionary biology, it is in fact motivated by an effort to undermine the teaching of science itself as a discipline based on the scientific method. Moreover, the key proponents of this methodology are not misguided scientists, they are highly refined political operatives who are motivated by a desire to incorporate religion directly in science classes.

  14. [The tropical rat mite Ornithonyssus bacoti attacks humans in Iceland.].

    PubMed

    Skírnisson, K

    2001-12-01

    In the summer of 2001 the obligate, intermittent tropical rat mite Ornithonyssus bacoti attacked humans in an Icelandic household where infected Mongolian gerbils (Meriones unguiculatus), bought in a local pet shop, had been kept for few months. After a rapid proliferation the mite started attacking the humans living in the house. A boy sharing room with the pets suffered from extensive dermatitis. Optimal conditions for O. bacoti are at 24-26 degrees C and a relative humidity of 47%. Similar conditions frequently occur indoors in Icelandic premises. Therefore, if O. bacoti has been noticed indoors, necessary measures should be undertaken to immediately eliminate the pest. PMID:17019023

  15. Jaguar attack on a child: case report and literature review.

    PubMed

    Iserson, Kenneth V; Francis, Adama M

    2015-03-01

    Jaguar attacks on humans rarely occur in the wild. When they do, they are often fatal. We describe a jaguar attack on a three-year-old girl near her home deep in a remote area of the Guyanese jungle. The patient had a complex but, relatively, rapid transport to a medical treatment facility for her life-threatening injuries. The child, who suffered typical jaguar-inflicted injury patterns and survived, is highlighted. We review jaguar anatomy, environmental status, hunting and killing behaviors, and discuss optimal medical management, given the resource-limited treatment environment of this international emergency medicine case.

  16. Patrol detection for replica attacks on wireless sensor networks.

    PubMed

    Wang, Liang-Min; Shi, Yang

    2011-01-01

    Replica attack is a critical concern in the security of wireless sensor networks. We employ mobile nodes as patrollers to detect replicas distributed in different zones in a network, in which a basic patrol detection protocol and two detection algorithms for stationary and mobile modes are presented. Then we perform security analysis to discuss the defense strategies against the possible attacks on the proposed detection protocol. Moreover, we show the advantages of the proposed protocol by discussing and comparing the communication cost and detection probability with some existing methods.

  17. Low aspect ratio wings at high angles of attack

    NASA Technical Reports Server (NTRS)

    Stallings, R. L., Jr.

    1986-01-01

    A comprehensive evaluation is made of experimental data compiled to date for the flowfields and aerodynamic forces that occur at high angles of attack for low aspect ratio wings with delta, rectangular, clipped delta, and strake/wing planform geometries. Attention is given to wing leading edge-generated vortex breakdown, aspect ratio and compressibility effects, and strake vortex effects on main wing areas. Although the nonlinear effects created by a wing-body combination significantly alter wing-alone aerodynamics, the wing-alone data presented are vital to the development of prediction methodologies for large angle of attack aerodynamics.

  18. A practical timing attack on RSA over a LAN

    NASA Astrophysics Data System (ADS)

    Lodato, Mark J.; Jouny, Ismail

    2006-04-01

    Today, the specific implementation of a cryptosystem is of possibly greater importance than the underlying cryptographic algorithm itself. Through side-channel cryptanalysis, an adversary may deduce a secret key just by monitoring implementation-specific side channels, such as execution time or power consumption during a cryptographic operation. In this paper, we describe a successful remote timing attack against a server running a protocol similar to SSL. Using a fully-automated attack on Chinese Remaindering Theorem (CRT) implementations of RSA, we show it is practical to recover a 1024-bit key in under an hour over a local area network.

  19. Jaguar Attack on a Child: Case Report and Literature Review

    PubMed Central

    Iserson, Kenneth V.; Francis, Adama M.

    2015-01-01

    Jaguar attacks on humans rarely occur in the wild. When they do, they are often fatal. We describe a jaguar attack on a three-year-old girl near her home deep in a remote area of the Guyanese jungle. The patient had a complex but, relatively, rapid transport to a medical treatment facility for her life-threatening injuries. The child, who suffered typical jaguar-inflicted injury patterns and survived, is highlighted. We review jaguar anatomy, environmental status, hunting and killing behaviors, and discuss optimal medical management, given the resource-limited treatment environment of this international emergency medicine case. PMID:25834674

  20. Comparison of X-31 Flight and Ground-Based Yawing Moment Asymmetries at High Angles of Attack

    NASA Technical Reports Server (NTRS)

    Cobleigh, Brent R.; Croom, Mark A.

    2001-01-01

    Significant yawing moment asymmetries were encountered during the high-angle-of-attack envelope expansion of the two X-31 aircraft. These asymmetries caused position saturations of the thrust-vectoring vanes and trailing-edge flaps during some stability-axis rolling maneuvers at high angles of attack. The two test aircraft had different asymmetry characteristics, and ship two has asymmetries that vary as a function of Reynolds number. Several aerodynamic modifications have been made to the X-31 forebody with the goal of minimizing the asymmetry. These modifications include adding transition strips on the forebody and noseboom, using two different length strakes, and increasing nose bluntness. Ultimately, a combination of forebody strakes, nose blunting, and noseboom transition strips reduced the yawing moment asymmetry enough to fully expand the high-angle-of-attack envelope. Analysis of the X-31 flight data is reviewed and compared to wind-tunnel and water-tunnel measurements. Several lessons learned are outlined regarding high-angle-of-attack configuration design and ground testing.

  1. Effect of bark beetle (Ips typographus L.) attack on bark VOC emissions of Norway spruce (Picea abies Karst.) trees

    NASA Astrophysics Data System (ADS)

    Ghimire, Rajendra P.; Kivimäenpää, Minna; Blomqvist, Minna; Holopainen, Toini; Lyytikäinen-Saarenmaa, Päivi; Holopainen, Jarmo K.

    2016-02-01

    Climate warming driven storms are evident causes for an outbreak of the European spruce bark beetle (Ips typographus L.) resulting in the serious destruction of mature Norway spruce (Picea abies Karst.) forests in northern Europe. Conifer species are major sources of biogenic volatile organic compounds (BVOCs) in the boreal zone. Climate relevant BVOC emissions are expected to increase when conifer trees defend against bark beetle attack by monoterpene (MT)-rich resin flow. In this study, BVOC emission rates from the bark surface of beetle-attacked and non-attacked spruce trees were measured from two outbreak areas, Iitti and Lahti in southern Finland, and from one control site at Kuopio in central Finland. Beetle attack increased emissions of total MTs 20-fold at Iitti compared to Kuopio, but decreased the emissions of several sesquiterpenes (SQTs) at Iitti. At the Lahti site, the emission rate of α-pinene was positively correlated with mean trap catch of bark beetles. The responsive individual MTs were tricyclene, α-pinene, camphene, myrcene, limonene, 1,8-cineole and bornyl acetate in both of the outbreak areas. Our results suggest that bark beetle outbreaks affect local BVOC emissions from conifer forests dominated by Norway spruce. Therefore, the impacts of insect outbreaks are worth of consideration to global BVOC emission models.

  2. Attack Methodology Analysis: Emerging Trends in Computer-Based Attack Methodologies and Their Applicability to Control System Networks

    SciTech Connect

    Bri Rolston

    2005-06-01

    Threat characterization is a key component in evaluating the threat faced by control systems. Without a thorough understanding of the threat faced by critical infrastructure networks, adequate resources cannot be allocated or directed effectively to the defense of these systems. Traditional methods of threat analysis focus on identifying the capabilities and motivations of a specific attacker, assessing the value the adversary would place on targeted systems, and deploying defenses according to the threat posed by the potential adversary. Too many effective exploits and tools exist and are easily accessible to anyone with access to an Internet connection, minimal technical skills, and a significantly reduced motivational threshold to be able to narrow the field of potential adversaries effectively. Understanding how hackers evaluate new IT security research and incorporate significant new ideas into their own tools provides a means of anticipating how IT systems are most likely to be attacked in the future. This research, Attack Methodology Analysis (AMA), could supply pertinent information on how to detect and stop new types of attacks. Since the exploit methodologies and attack vectors developed in the general Information Technology (IT) arena can be converted for use against control system environments, assessing areas in which cutting edge exploit development and remediation techniques are occurring can provide significance intelligence for control system network exploitation, defense, and a means of assessing threat without identifying specific capabilities of individual opponents. Attack Methodology Analysis begins with the study of what exploit technology and attack methodologies are being developed in the Information Technology (IT) security research community within the black and white hat community. Once a solid understanding of the cutting edge security research is established, emerging trends in attack methodology can be identified and the gap between

  3. Hydrogen attack - Influence of hydrogen sulfide. [on carbon steel

    NASA Technical Reports Server (NTRS)

    Eliezer, D.; Nelson, H. G.

    1978-01-01

    An experimental study is conducted on 12.5-mm-thick SAE 1020 steel (plain carbon steel) plate to assess hydrogen attack at room temperature after specimen exposure at 525 C to hydrogen and a blend of hydrogen sulfide and hydrogen at a pressure of 3.5 MN/sq m for exposure times up to 240 hr. The results are discussed in terms of tensile properties, fissure formation, and surface scales. It is shown that hydrogen attack from a high-purity hydrogen environment is severe, with the formation of numerous methane fissures and bubbles along with a significant reduction in the room-temperature tensile yield and ultimate strengths. However, no hydrogen attack is observed in the hydrogen/hydrogen sulfide blend environment, i.e. no fissure or bubble formation occurred and the room-temperature tensile properties remained unchanged. It is suggested that the observed porous discontinuous scale of FeS acts as a barrier to hydrogen entry, thus reducing its effective equilibrium solubility in the iron lattice. Therefore, hydrogen attack should not occur in pressure-vessel steels used in many coal gasification processes.

  4. Possibility of spoof attack against robustness of multibiometric authentication systems

    NASA Astrophysics Data System (ADS)

    Hariri, Mahdi; Shokouhi, Shahriar Baradaran

    2011-07-01

    Multibiometric systems have been recently developed in order to overcome some weaknesses of single biometric authentication systems, but security of these systems against spoofing has not received enough attention. In this paper, we propose a novel practical method for simulation of possibilities of spoof attacks against a biometric authentication system. Using this method, we model matching scores from standard to completely spoofed genuine samples. Sum, product, and Bayes fusion rules are applied for score level combination. The security of multimodal authentication systems are examined and compared with the single systems against various spoof possibilities. However, vulnerability of fused systems is considerably increased against spoofing, but their robustness is generally higher than single matcher systems. In this paper we show that robustness of a combined system is not always higher than a single system against spoof attack. We propose empirical methods for upgrading the security of multibiometric systems, which contain how to organize and select biometric traits and matchers against various possibilities of spoof attack. These methods provide considerable robustness and present an appropriate reason for using combined systems against spoof attacks.

  5. Sleep Deprivation Attack Detection in Wireless Sensor Network

    NASA Astrophysics Data System (ADS)

    Bhattasali, Tapalina; Chaki, Rituparna; Sanyal, Sugata

    2012-02-01

    Deployment of sensor network in hostile environment makes it mainly vulnerable to battery drainage attacks because it is impossible to recharge or replace the battery power of sensor nodes. Among different types of security threats, low power sensor nodes are immensely affected by the attacks which cause random drainage of the energy level of sensors, leading to death of the nodes. The most dangerous type of attack in this category is sleep deprivation, where target of the intruder is to maximize the power consumption of sensor nodes, so that their lifetime is minimized. Most of the existing works on sleep deprivation attack detection involve a lot of overhead, leading to poor throughput. The need of the day is to design a model for detecting intrusions accurately in an energy efficient manner. This paper proposes a hierarchical framework based on distributed collaborative mechanism for detecting sleep deprivation torture in wireless sensor network efficiently. Proposed model uses anomaly detection technique in two steps to reduce the probability of false intrusion.

  6. Extracranial arterial aneurysms: a cause of crescendo transient ischaemic attacks.

    PubMed

    Paterson, H M; Holdsworth, R J

    2000-12-01

    Crescendo transient ischaemic attacks (TIAs) should be regarded as a medical emergency. Patients require hospitalisation with urgent assessment and symptom control with anticoagulant therapy. We report on three patients, all of whom had atherosclerotic aneurysmal disease of the extracranial arterial circulation who presented with crescendo TIAs. The possibility of extracranial aneurysmal disease should always be considered and excluded.

  7. Angle of Attack Modulation for Mars Entry Terminal State Optimization

    NASA Technical Reports Server (NTRS)

    Lafleur, Jarret M.; Cerimele, Christopher J.

    2009-01-01

    From the perspective of atmospheric entry, descent, and landing (EDL), one of the most foreboding destinations in the solar system is Mars due in part to its exceedingly thin atmosphere. To benchmark best possible scenarios for evaluation of potential Mars EDL system designs, a study is conducted to optimize the entry-to-terminal-state portion of EDL for a variety of entry velocities and vehicle masses, focusing on the identification of potential benefits of enabling angle of attack modulation. The terminal state is envisioned as one appropriate for the initiation of terminal descent via parachute or other means. A particle swarm optimizer varies entry flight path angle, ten bank profile points, and ten angle of attack profile points to find maximum-final-altitude trajectories for a 10 30 m ellipsled at 180 different combinations of values for entry mass, entry velocity, terminal Mach number, and minimum allowable altitude. Parametric plots of maximum achievable altitude are shown, as are examples of optimized trajectories. It is shown that appreciable terminal state altitude gains (2.5-4.0 km) over pure bank angle control may be possible if angle of attack modulation is enabled for Mars entry vehicles. Gains of this magnitude could prove to be enabling for missions requiring high-altitude landing sites. Conclusions are also drawn regarding trends in the bank and angle of attack profiles that produce the optimal trajectories in this study, and directions for future work are identified.

  8. Assessment and Intervention for Academic Task Attack Strategy Competencies

    ERIC Educational Resources Information Center

    Busse, R. T.; Lee, Charlene

    2015-01-01

    Many students who underachieve in schools may not be learning as effectively as they could. Direct assessments such as the Academic Competence Evaluation Scales (ACES), School Motivation and Learning Strategies Inventory (SMALSI), and the Academic Task Attack Checklist System (ATACS) can be used to evaluate students' knowledge and use of…

  9. Management of victims of urban chemical attack: the French approach.

    PubMed

    Laurent, J F; Richter, F; Michel, A

    1999-10-01

    Since the early 1980s several disasters involving mass release of toxic substances have focused the attention of different administrations and the fire services into producing protocols and guidelines for action in civilian situations. The bomb attack in the Tokyo subway, in March 1995, made it clear that a terrorist attack using highly toxic agents is now feasible. Management of disasters in the civil sector in France is based upon two interlinked plans: the Red Plan, which covers on-site organisation, and the White Plan, which concerns the interface with hospital services. Special procedures have been developed to adapt the Red and White Plans for use in the event of toxic attack and concern the deployment of emergency responding personnel, the provision of life support and antidotes in the contaminated zone, the prevention of secondary contamination and the transport and reception of victims at the hospital. Based on the established principle of pre-hospital resuscitation and well-tried assistance plans, this doctrine allows a safe and effective response to terrorist attacks as well as to other toxic release incidents. PMID:10617333

  10. Male Brown-headed Cowbird Attacks and Kills a Nestling

    USGS Publications Warehouse

    Igl, L.D.

    2003-01-01

    I observed a male Brown-headed Cowbird (Molothrus ater) attack and kill a nestling of an unidentified passerine in a grassland field in Day County, South Dakota, in June 2000. The killing or removal of nestlings by female cowbirds has been reported by others, but this behavior has not been documented previously in male cowbirds.

  11. Optimality of Gaussian attacks in continuous-variable quantum cryptography.

    PubMed

    Navascués, Miguel; Grosshans, Frédéric; Acín, Antonio

    2006-11-10

    We analyze the asymptotic security of the family of Gaussian modulated quantum key distribution protocols for continuous-variables systems. We prove that the Gaussian unitary attack is optimal for all the considered bounds on the key rate when the first and second momenta of the canonical variables involved are known by the honest parties.

  12. Exercise Following a Heart Attack: Some Special Considerations.

    ERIC Educational Resources Information Center

    Fardy, Paul S.

    This paper presents information on the effectiveness of exercise programs for heart attack victims. Some of the observations come from unpublished results of a two year experiment of the National Exercise and Heart Disease Project. The paper first establishes that a group exercise program with trained supervision is advantageous for people with…

  13. Imaging Recommendations for Acute Stroke and Transient Ischemic Attack Patients

    PubMed Central

    Wintermark, Max; Sanelli, Pina C.; Albers, Gregory W.; Bello, Jacqueline A.; Derdeyn, Colin P.; Hetts, Steven W.; Johnson, Michele H.; Kidwell, Chelsea S.; Lev, Michael H.; Liebeskind, David S.; Rowley, Howard A.; Schaefer, Pamela W.; Sunshine, Jeffrey L.; Zaharchuk, Greg; Meltzer, Carolyn C.

    2014-01-01

    In the article entitled “Imaging Recommendations for Acute Stroke and Transient Ischemic Attack Patients: A Joint Statement by the American Society of Neuroradiology, the American College of Radiology and the Society of NeuroInterventional Surgery”, we are proposing a simple, pragmatic approach that will allow the reader to develop an optimal imaging algorithm for stroke patients at their institution. PMID:23948676

  14. The Tokyo subway sarin attack--lessons learned.

    PubMed

    Okumura, T; Hisaoka, T; Yamada, A; Naito, T; Isonuma, H; Okumura, S; Miura, K; Sakurada, M; Maekawa, H; Ishimatsu, S; Takasu, N; Suzuki, K

    2005-09-01

    The sarin gas attack in the Tokyo subway system is reviewed from a clinical toxicology perspective. Based on the lessons learned from this attack, the following areas should be addressed on a global scale. First, an adequate supply of protective equipment is required, including level B protective equipment with a pressure demand breathing apparatus. In addition, a system should be established that enables a possible cause to be determined based on symptoms, physical findings, general laboratory tests, and a simple qualitative analysis for poisonous substances. If an antidote is needed, the system should enable it to be administered to the victims as quickly as possible. Preparation for a large-scale chemical attack by terrorists requires the prior establishment of a detailed decontamination plan that utilizes not only mass decontamination facilities but also public facilities in the area. A system should be established for summarizing, evaluating, and disseminating information on poisonous substances. Finally, a large-scale scientific investigation of the Tokyo sarin attack should be conducted to examine its long-term and subclinical effects and the effects of exposure to asymptomatic low levels of sarin.

  15. Posttraumatic Stress Disorder Following the September 11, 2001, Terrorist Attacks

    PubMed Central

    Neria, Yuval; DiGrande, Laura; Adams, Ben G.

    2012-01-01

    The September 11, 2001 (9/11), terrorist attacks were unprecedented in their magnitude and aftermath. In the wake of the attacks, researchers reported a wide range of mental and physical health outcomes, with posttraumatic stress disorder (PTSD) the one most commonly studied. In this review, we aim to assess the evidence about PTSD among highly exposed populations in the first 10 years after the 9/11 attacks. We performed a systematic review. Eligible studies included original reports based on the full Diagnostic and Statistical Manual of Mental Disorders (4th ed., rev.; American Psychiatric Association, 2000) criteria of PTSD among highly exposed populations such as those living or working within close proximity to the World Trade Center (WTC) and the Pentagon in New York City and Washington, DC, respectively, and first responders, including rescue, cleaning, and recovery workers. The large body of research conducted after the 9/11 attacks in the past decade suggests that the burden of PTSD among persons with high exposure to 9/11 was substantial. PTSD that was 9/11-related was associated with a wide range of correlates, including sociodemographic and background factors, event exposure characteristics, loss of life of significant others, and social support factors. Few studies used longitudinal study design or clinical assessments, and no studies reported findings beyond six years post-9/11, thus hindering documentation of the long-term course of confirmed PTSD. Future directions for research are discussed. PMID:21823772

  16. Vulnerabilities in GSM technology and feasibility of selected attacks

    NASA Astrophysics Data System (ADS)

    Voznak, M.; Prokes, M.; Sevcik, L.; Frnda, J.; Toral-Cruz, Homer; Jakovlev, Sergej; Fazio, Peppino; Mehic, M.; Mikulec, M.

    2015-05-01

    Global System for Mobile communication (GSM) is the most widespread technology for mobile communications in the world and serving over 7 billion users. Since first publication of system documentation there has been notified a potential safety problem's occurrence. Selected types of attacks, based on the analysis of the technical feasibility and the degree of risk of these weaknesses, were implemented and demonstrated in laboratory of the VSB-Technical University of Ostrava, Czech Republic. These vulnerabilities were analyzed and afterwards possible attacks were described. These attacks were implemented using open-source tools, software programmable radio USRP (Universal Software RadioPeripheral) and DVB-T (Digital Video Broadcasting - Terrestrial) receiver. GSM security architecture is being scrutinized since first public releases of its specification mainly pointing out weaknesses in authentication and ciphering mechanisms. This contribution also summarizes practically proofed and used scenarios that are performed using opensource software tools and variety of scripts mostly written in Python. Main goal of this paper is in analyzing security issues in GSM network and practical demonstration of selected attacks.

  17. Risk assessment for physical and cyber attacks on critical infrastructures.

    SciTech Connect

    Smith, Bryan J.; Sholander, Peter E.; Phelan, James M.; Wyss, Gregory Dane; Varnado, G. Bruce; Depoy, Jennifer Mae

    2005-08-01

    Assessing the risk of malevolent attacks against large-scale critical infrastructures requires modifications to existing methodologies. Existing risk assessment methodologies consider physical security and cyber security separately. As such, they do not accurately model attacks that involve defeating both physical protection and cyber protection elements (e.g., hackers turning off alarm systems prior to forced entry). This paper presents a risk assessment methodology that accounts for both physical and cyber security. It also preserves the traditional security paradigm of detect, delay and respond, while accounting for the possibility that a facility may be able to recover from or mitigate the results of a successful attack before serious consequences occur. The methodology provides a means for ranking those assets most at risk from malevolent attacks. Because the methodology is automated the analyst can also play 'what if with mitigation measures to gain a better understanding of how to best expend resources towards securing the facilities. It is simple enough to be applied to large infrastructure facilities without developing highly complicated models. Finally, it is applicable to facilities with extensive security as well as those that are less well-protected.

  18. The Rape of a Discipline: Home Economics under Attack.

    ERIC Educational Resources Information Center

    Thompson, Patricia J.

    Changes in a Home Economics curriculum at Lehman College of the City University of New York from 1979-1988 are examined, and a line of inquiry first reported in 1983 is continued. A secondary, feminist analysis of the earlier data, combined with the current data, discloses the extent to which the patriarchal academy will go to attack the "mental…

  19. Cultural Connections: Bowl with Frieze of Lions Attacking Bulls

    ERIC Educational Resources Information Center

    School Arts: The Art Education Magazine for Teachers, 2004

    2004-01-01

    This article gives a brief description of the piece of art titled "Bowl with Frieze of Lions Attacking Bulls" which is thought to be the product of a court or palace of the Neo-Assyrian period and dates to the late seventh to eighth century BC, between the reigns of Sargon and Ashurbanipal. The article highlights the piece's most notable cultural…

  20. Molten Salt Techniques for Students: Attacking Hematite with Pyrosulfate.

    ERIC Educational Resources Information Center

    Atkinson, George F.

    1986-01-01

    Discusses materials needed, procedures used, and typical results obtained for an experiment involving a dry attack of ores with pyrosulfate flux. The experiment has been carried out by about 150 students a year with a demonstrator-to-student ratio of about 1:15 with no serious accidents. (JN)

  1. Assessing Sexual Abuse/Attack Histories with Bariatric Surgery Patients

    ERIC Educational Resources Information Center

    Mahony, David

    2010-01-01

    This study assessed sexual abuse/attack histories in 537 bariatric surgery patients using the PsyBari. The prevalence rates found were lower (15.5%, 19.3% of women, 5.2% of men) than other studies that used bariatric surgery patients but consistent with studies that used nonbariatric obese subjects. Furthermore, bariatric surgery patients who…

  2. X-31 high angle of attack control system performance

    NASA Technical Reports Server (NTRS)

    Huber, Peter; Seamount, Patricia

    1994-01-01

    The design goals for the X-31 flight control system were: (1) level 1 handling qualities during post-stall maneuvering (30 to 70 degrees angle-of-attack); (2) thrust vectoring to enhance performance across the flight envelope; and (3) adequate pitch-down authority at high angle-of-attack. Additional performance goals are discussed. A description of the flight control system is presented, highlighting flight control system features in the pitch and roll axes and X-31 thrust vectoring characteristics. The high angle-of-attack envelope clearance approach will be described, including a brief explanation of analysis techniques and tools. Also, problems encountered during envelope expansion will be discussed. This presentation emphasizes control system solutions to problems encountered in envelope expansion. An essentially 'care free' envelope was cleared for the close-in-combat demonstrator phase. High angle-of-attack flying qualities maneuvers are currently being flown and evaluated. These results are compared with pilot opinions expressed during the close-in-combat program and with results obtained from the F-18 HARV for identical maneuvers. The status and preliminary results of these tests are discussed.

  3. Experimental eavesdropping attack against Ekert's protocol based on Wigner's inequality

    SciTech Connect

    Bovino, F. A.; Colla, A. M.; Castagnoli, G.; Castelletto, S.; Degiovanni, I. P.; Rastello, M. L.

    2003-09-01

    We experimentally implemented an eavesdropping attack against the Ekert protocol for quantum key distribution based on the Wigner inequality. We demonstrate a serious lack of security of this protocol when the eavesdropper gains total control of the source. In addition we tested a modified Wigner inequality which should guarantee a secure quantum key distribution.

  4. Revising School Attack Protections since 9/11

    ERIC Educational Resources Information Center

    Black, Susan

    2004-01-01

    The terrorist attacks of September 11, 2001, prompted federal officials to step up campaigns to make schools safe. After visiting Ground Zero at New York City's World Trade Center, Education Secretary Rodney Paige sent each chief state school officer suggestions for managing school crises. Many states also have school safety plans in place. New…

  5. Parent-Reported Predictors of Adolescent Panic Attacks.

    ERIC Educational Resources Information Center

    Hayward, Chris; Wilson, Kimberly A.; Lagle, Kristy; Killen, Joel D.; Taylor, C. Barr

    2004-01-01

    Objective: To identify parent-reported risk factors for adolescent panic attacks. Method: Structured diagnostic interviews were obtained from 770 parents of participants in a school-based risk factor study for adolescent panic. Parent-reported risk factors assessed included characteristics of the child (negative affect, separation anxiety disorder…

  6. Defeating Insider Attacks via Autonomic Self-Protective Networks

    ERIC Educational Resources Information Center

    Sibai, Faisal M.

    2012-01-01

    There has been a constant growing security concern with insider attacks on network accessible computer systems. Users with power credentials can do almost anything they want with the systems they own with very little control or oversight. Most breaches occurring nowadays by power users are considered legitimate access and not necessarily…

  7. Attacks on the Freedom To Learn. 1986-1987 Report.

    ERIC Educational Resources Information Center

    People for the American Way, Washington, DC.

    Documenting a cumulative attack on the freedom to learn, which strikes at the heart of public education, this report describes how censorship has grown since 1982, highlighting trends that have emerged over five years, the actors, the challenges, and the results. Following an introduction, the report documents the state of censorship for…

  8. What Should We Expect after the next Attack?

    ERIC Educational Resources Information Center

    Silver, Roxane Cohen; Fischhoff, Baruch

    2011-01-01

    A test of any science is its ability to predict events under specified conditions. A test for the psychology represented in this special issue of the American Psychologist is its ability to predict individual and social behavior in the aftermath of a next terror attack. This article draws on that science to make such predictions. These predictions…

  9. Endangered Education: How Corporate Polluters Are Attacking Environmental Education.

    ERIC Educational Resources Information Center

    Bohart, Barbara; Manilov, Marianne; Schwarz, Tamara

    This report claims that an attack has been waged on environmental education to derail the re-authorization of the National Environmental Education Act and to de-stabilize and de-fund environmental education in the United States. Presented in the media as a grassroots movement, stories have appeared in local, state, and national media that…

  10. Hypergame theory applied to cyber attack and defense

    NASA Astrophysics Data System (ADS)

    House, James Thomas; Cybenko, George

    2010-04-01

    This work concerns cyber attack and defense in the context of game theory--specifically hypergame theory. Hypergame theory extends classical game theory with the ability to deal with differences in players' expertise, differences in their understanding of game rules, misperceptions, and so forth. Each of these different sub-scenarios, or subgames, is associated with a probability--representing the likelihood that the given subgame is truly "in play" at a given moment. In order to form an optimal attack or defense policy, these probabilities must be learned if they're not known a-priori. We present hidden Markov model and maximum entropy approaches for accurately learning these probabilities through multiple iterations of both normal and modified game play. We also give a widely-applicable approach for the analysis of cases where an opponent is aware that he is being studied, and intentionally plays to spoil the process of learning and thereby obfuscate his attributes. These are considered in the context of a generic, abstract cyber attack example. We demonstrate that machine learning efficacy can be heavily dependent on the goals and styles of participant behavior. To this end detailed simulation results under various combinations of attacker and defender behaviors are presented and analyzed.

  11. Delimiting Democratic Debate: The Fordham Institute's Attack on Democratic Values

    ERIC Educational Resources Information Center

    Leahey, Christopher R.

    2005-01-01

    Reflecting on the current debate on how to teach about the terrorist attacks of September 11, 2001, and the subsequent U.S. invasions of Afghanistan and Iraq, this article examines Thomas B. Fordham Institute's Terrorists, Despots, and Democracy: What Our Children Need to Know, one of the several publications produced by the Fordham Institute that…

  12. Protecting water and wastewater infrastructure from cyber attacks

    NASA Astrophysics Data System (ADS)

    Panguluri, Srinivas; Phillips, William; Cusimano, John

    2011-12-01

    Multiple organizations over the years have collected and analyzed data on cyber attacks and they all agree on one conclusion: cyber attacks are real and can cause significant damages. This paper presents some recent statistics on cyber attacks and resulting damages. Water and wastewater utilities must adopt countermeasures to prevent or minimize the damage in case of such attacks. Many unique challenges are faced by the water and wastewater industry while selecting and implementing security countermeasures; the key challenges are: 1) the increasing interconnection of their business and control system networks, 2) large variation of proprietary industrial control equipment utilized, 3) multitude of cross-sector cyber-security standards, and 4) the differences in the equipment vendor's approaches to meet these security standards. The utilities can meet these challenges by voluntarily selecting and adopting security standards, conducting a gap analysis, performing vulnerability/risk analysis, and undertaking countermeasures that best meets their security and organizational requirements. Utilities should optimally utilize their limited resources to prepare and implement necessary programs that are designed to increase cyber-security over the years. Implementing cyber security does not necessarily have to be expensive, substantial improvements can be accomplished through policy, procedure, training and awareness. Utilities can also get creative and allocate more funding through annual budgets and reduce dependence upon capital improvement programs to achieve improvements in cyber-security.

  13. Technosocial Modeling of IED Threat Scenarios and Attacks

    SciTech Connect

    Whitney, Paul D.; Brothers, Alan J.; Coles, Garill A.; Young, Jonathan; Wolf, Katherine E.; Thompson, Sandra E.; Niesen, David A.; Madsen, John M.; Henderson, Cynthia L.

    2009-03-23

    This paper describes an approach for integrating sociological and technical models to develop more complete threat assessment. Current approaches to analyzing and addressing threats tend to focus on the technical factors. This paper addresses development of predictive models that encompass behavioral as well as these technical factors. Using improvised explosive device (IED) attacks as motivation, this model supports identification of intervention activities 'left of boom' as well as prioritizing attack modalities. We show how Bayes nets integrate social factors associated with IED attacks into general threat model containing technical and organizational steps from planning through obtaining the IED to initiation of the attack. The social models are computationally-based representations of relevant social science literature that describes human decision making and physical factors. When combined with technical models, the resulting model provides improved knowledge integration into threat assessment for monitoring. This paper discusses the construction of IED threat scenarios, integration of diverse factors into an analytical framework for threat assessment, indicator identification for future threats, and future research directions.

  14. Database Relation Watermarking Resilient against Secondary Watermarking Attacks

    NASA Astrophysics Data System (ADS)

    Gupta, Gaurav; Pieprzyk, Josef

    There has been tremendous interest in watermarking multimedia content during the past two decades, mainly for proving ownership and detecting tamper. Digital fingerprinting, that deals with identifying malicious user(s), has also received significant attention. While extensive work has been carried out in watermarking of images, other multimedia objects still have enormous research potential. Watermarking database relations is one of the several areas which demand research focus owing to the commercial implications of database theft. Recently, there has been little progress in database watermarking, with most of the watermarking schemes modeled after the irreversible database watermarking scheme proposed by Agrawal and Kiernan. Reversibility is the ability to re-generate the original (unmarked) relation from the watermarked relation using a secret key. As explained in our paper, reversible watermarking schemes provide greater security against secondary watermarking attacks, where an attacker watermarks an already marked relation in an attempt to erase the original watermark. This paper proposes an improvement over the reversible and blind watermarking scheme presented in [5], identifying and eliminating a critical problem with the previous model. Experiments showing that the average watermark detection rate is around 91% even with attacker distorting half of the attributes. The current scheme provides security against secondary watermarking attacks.

  15. Fast WEP-Key Recovery Attack Using Only Encrypted IP Packets

    NASA Astrophysics Data System (ADS)

    Teramura, Ryoichi; Asakura, Yasuo; Ohigashi, Toshihiro; Kuwakado, Hidenori; Morii, Masakatu

    Conventional efficient key recovery attacks against Wired Equivalent Privacy (WEP) require specific initialization vectors or specific packets. Since it takes much time to collect the packets sufficiently, any active attack should be performed. An Intrusion Detection System (IDS), however, will be able to prevent the attack. Since the attack logs are stored at the servers, it is possible to prevent such an attack. This paper proposes an algorithm for recovering a 104-bit WEP key from any IP packets in a realistic environment. This attack needs about 36, 500 packets with a success probability 0.5, and the complexity of our attack is equivalent to about 220 computations of the RC4 key setups. Since our attack is passive, it is difficult for both WEP users and administrators to detect our attack.

  16. Novel mechanism of network protection against the new generation of cyber attacks

    NASA Astrophysics Data System (ADS)

    Milovanov, Alexander; Bukshpun, Leonid; Pradhan, Ranjit

    2012-06-01

    A new intelligent mechanism is presented to protect networks against the new generation of cyber attacks. This mechanism integrates TCP/UDP/IP protocol stack protection and attacker/intruder deception to eliminate existing TCP/UDP/IP protocol stack vulnerabilities. It allows to detect currently undetectable, highly distributed, low-frequency attacks such as distributed denial-of-service (DDoS) attacks, coordinated attacks, botnet, and stealth network reconnaissance. The mechanism also allows insulating attacker/intruder from the network and redirecting the attack to a simulated network acting as a decoy. As a result, network security personnel gain sufficient time to defend the network and collect the attack information. The presented approach can be incorporated into wireless or wired networks that require protection against known and the new generation of cyber attacks.

  17. Attack propagation of high-powered intrachannel crosstalk in transparent optical networks

    NASA Astrophysics Data System (ADS)

    Sun, Zeyu; Peng, Yunfeng; Long, Keping

    2011-10-01

    Transparent optical networks (TON) are becoming increasingly attractive, but transparency introduces security threats, e.g., intrachannel crosstalk attack, to optical networks. In this letter, three attack scenarios, i.e., attack propagation within an optical cross connect (OXC), the secondary attacker traverses successive OXCs and original attacker traverses successive OXCs, are investigated. The scenarios accompanied with gain competition attack are also simulated as comparison. Bit-error-rate (BER), and eye diagram penalties are estimated via VPItransMakerTM. Our work proved that the attack signal will propagate intrachannel crosstalk attack to successive three OXCs but with limited two stages of optical switches in each OXC. The BER will be somewhat higher in case gain competition attack exists. The results will be useful for future managing, planning, and designing on TONs.

  18. Exploiting Small Leakages in Masks to Turn a Second-Order Attack into a First-Order Attack and Improved Rotating Substitution Box Masking with Linear Code Cosets

    PubMed Central

    DeTrano, Alexander; Karimi, Naghmeh; Karri, Ramesh; Guo, Xiaofei; Carlet, Claude; Guilley, Sylvain

    2015-01-01

    Masking countermeasures, used to thwart side-channel attacks, have been shown to be vulnerable to mask-extraction attacks. State-of-the-art mask-extraction attacks on the Advanced Encryption Standard (AES) algorithm target S-Box recomputation schemes but have not been applied to scenarios where S-Boxes are precomputed offline. We propose an attack targeting precomputed S-Boxes stored in nonvolatile memory. Our attack targets AES implemented in software protected by a low entropy masking scheme and recovers the masks with 91% success rate. Recovering the secret key requires fewer power traces (in fact, by at least two orders of magnitude) compared to a classical second-order attack. Moreover, we show that this attack remains viable in a noisy environment or with a reduced number of leakage points. Eventually, we specify a method to enhance the countermeasure by selecting a suitable coset of the masks set. PMID:26491717

  19. Exploiting Small Leakages in Masks to Turn a Second-Order Attack into a First-Order Attack and Improved Rotating Substitution Box Masking with Linear Code Cosets.

    PubMed

    DeTrano, Alexander; Karimi, Naghmeh; Karri, Ramesh; Guo, Xiaofei; Carlet, Claude; Guilley, Sylvain

    2015-01-01

    Masking countermeasures, used to thwart side-channel attacks, have been shown to be vulnerable to mask-extraction attacks. State-of-the-art mask-extraction attacks on the Advanced Encryption Standard (AES) algorithm target S-Box recomputation schemes but have not been applied to scenarios where S-Boxes are precomputed offline. We propose an attack targeting precomputed S-Boxes stored in nonvolatile memory. Our attack targets AES implemented in software protected by a low entropy masking scheme and recovers the masks with 91% success rate. Recovering the secret key requires fewer power traces (in fact, by at least two orders of magnitude) compared to a classical second-order attack. Moreover, we show that this attack remains viable in a noisy environment or with a reduced number of leakage points. Eventually, we specify a method to enhance the countermeasure by selecting a suitable coset of the masks set. PMID:26491717

  20. The impact of repetitive and chronic exposure to terror attacks on Israeli mothers' and children's functioning.

    PubMed

    Shechory-Bitton, Mally

    2013-01-01

    Studies point to the pathogenic impact of exposure to terror. however, most focus on specific traumatic events. the current study focused on the impact of continuous ongoing exposure to terror attacks. it examined the extent to which children's PtSD and behavior problems are a function of mothers' PtSD, child and mother exposure to terror events, and child and mother fear. a sample of 152 mother and children dyads, all living in communities on israel's southern border, were surveyed. results indicate that children's posttraumatic symptoms are significantly and positively predicted by their exposure to terror events, their fear, and their mothers' posttraumatic symptoms. in addition, children's current behavioral and social problems are positively predicted by mothers' posttraumatic symptoms. results are discussed in light of the importance of subjective interpretation. the findings suggest that further research should examine additional cognitive and social contextual factors.

  1. Buffeting of NACA 0012 airfoil at high angle of attack

    NASA Astrophysics Data System (ADS)

    Zhou, Tong; Dowell, Earl

    2014-11-01

    Buffeting is a fluid instability caused by flow separation or shock wave oscillations in the flow around a bluff body. Typically there is a dominant frequency of these flow oscillations called Strouhal or buffeting frequency. In prior work several researchers at Duke University have noted the analogy between the classic Von Karman Vortex Street behind a bluff body and the flow oscillations that occur for flow around a NACA 0012 airfoil at sufficiently large angle of attack. Lock-in is found for certain combinations of airfoil oscillation (pitching motion) frequencies and amplitudes when the frequency of the airfoil motion is sufficiently close to the buffeting frequency. The goal of this paper is to explore the flow around a static and an oscillating airfoil at high angle of attack by developing a method for computing buffet response. Simulation results are compared with experimental data. Conditions for the onset of buffeting and lock-in of a NACA 0012 airfoil at high angle of attack are determined. Effects of several parameters on lift coefficient and flow response frequency are studied including Reynolds number, angle of attack and blockage ratio of the airfoil size to the wind tunnel dimensions. Also more detailed flow field characteristics are determined. For a static airfoil, a universal Strouhal number scaling has been found for angles of attack from 30° to 90°, where the flow around airfoil is fully separated. For an oscillating airfoil, conditions for lock-in are discussed. Differences between the lock-in case and the unlocked case are also studied. The second affiliation: Duke University.

  2. Attacks by packs of dogs involving predation on human beings

    PubMed Central

    Borchelt, Peter L.; Lockwood, Randall; Beck, Alan M.; Voith, Victoria L.

    1983-01-01

    Dog bites are a medical problem for millions of people, children being the most common victims. Human deaths attributable to dog bite injury (not rabies) are relatively infrequent. There have been some epidemiologic reviews, but this study is the first attempt to arrive at an understanding of bites involving predation on human beings by conducting behavioral examinations under controlled conditions of the dogs involved, and by interviewing victims, witnesses, and people familiar with the animals. The three cases studied involved two fatalities and an attack that was nearly fatal. The victims were 11, 14, and 81. In each case, owned pet dogs consumed some human tissue. The severity of the victims' injuries was not the consequence of a single dog bite, but the result of repeated attacks by dogs behaving as a social group. Factors that might contribute to a dog's regarding human beings as potential prey were examined, including hunger, prior predation, group behaviors, defense of territory, previous interactions with people, the presence of estrous female dogs, and environmental stimuli. In two of the cases, it was possible, by using similar stimuli, to duplicate the circumstances at the time of the attack. The results of the observations showed the value of behavioral analysis and simulations methods in evaluating possible factors in dog attacks. Among the many factors probably involved in severe dog attacks are the size, number, and nutritional status of the dogs; the dogs' previous aggressive contacts with people; the victim's age, size, health, and behavior; and the absence of other human beings in the vicinity. Imagesp61-ap61-bp61-c PMID:6828639

  3. Benign paroxysmal positional vertigo after radiologic scanning: a case series

    PubMed Central

    Aydin, Erdinc; Akman, Kubra; Yerli, Hasan; Ozluoglu, Levent N

    2008-01-01

    Introduction Benign paroxysmal positional vertigo (BPPV) is the most common type of vertigo. It is frequently seen in elderly patients, and the course of the attack may easily mimic cerebrovascular disease. A BPPV attack after a radiologic examination has not been reported previously. We report the cases of two patients who had BPPV attacks after radiologic imaging. Case presentation The first patient with headache and tremor was admitted to the radiology department for cranial computed tomography (CT) imaging. During scanning, she was asked to lie in the supine position with no other head movements for approximately 10 minutes. After the cranial CT imaging, she stood up rapidly, and suddenly experienced a vertigo attack and nausea. The second patient was admitted to the radiology department for evaluation of his renal arteries. During the renal magnetic resonance angiography, he was in the supine position for 20 minutes and asked not to move. After the examination, he stood up rapidly with the help of the technician and suddenly experienced a vertigo attack with nausea and vomiting. The results of standard laboratory analyses and their neurologic examinations were within normal limits and Dix-Hallpike tests showed rotatory nystagmus in both cases. An Epley maneuver was performed to the patients. The results of a control Dix-Hallpike tests after 1 Epley maneuver were negative in both patients. Conclusion Radiologists and clinicians must keep in mind that after radiologic imaging in which the patient is still for some time in the supine position and then helped to stand up rapidly, a BPPV attack may occur. PMID:18371218

  4. A Consistency-Based Secure Localization Scheme against Wormhole Attacks in WSNs

    NASA Astrophysics Data System (ADS)

    Chen, Honglong; Lou, Wei; Wang, Zhi

    Wormhole attacks can negatively affect the localization in wireless sensor networks. A typical wormhole attack can be launched by two colluding external attackers, one of which sniffs packets at one point in the network, tunnels them through a wired or wireless link to another point, and the other of which relays them within its vicinity. In this paper, we investigate the impact of the wormhole attack on the localization process and propose a novel consistency-based secure localization scheme against wormhole attacks, which includes wormhole attack detection, valid locators identification and self-localization. We also conduct the simulations to demonstrate the effectiveness of our proposed scheme.

  5. The anatomy of a shark attack: a case report and review of the literature.

    PubMed

    Caldicott, D G; Mahajani, R; Kuhn, M

    2001-07-01

    Shark attacks are rare but are associated with a high morbidity and significant mortality. We report the case of a patient's survival from a shark attack and their subsequent emergency medical and surgical management. Using data from the International Shark Attack File, we review the worldwide distribution and incidence of shark attack. A review of the world literature examines the features which make shark attacks unique pathological processes. We offer suggestions for strategies of management of shark attack, and techniques for avoiding adverse outcomes in human encounters with these endangered creatures.

  6. Pre-Attack Stress-Load, Appraisals, and Coping in Children's Responses to the 9/11 Terrorist Attacks

    ERIC Educational Resources Information Center

    Lengua, Liliana J.; Long, Anna C.; Meltzoff, Andrew N.

    2006-01-01

    Background: Appraisal and coping following a disaster are important factors in children's post-traumatic stress (PTS) symptoms. However, little is known about predictors of disaster coping responses. This study examined stress-load, appraisals and coping styles measured prior to the September 11 terrorist attacks as predictors of 9/11-specific…

  7. Benign paroxysmal positional vertigo after nonotologic surgery: case series.

    PubMed

    Kansu, Leyla; Aydin, Erdinc; Gulsahi, Kamran

    2015-03-01

    Benign paroxysmal positional vertigo is one of the most common types of vertigo caused by peripheral vestibular dysfunction. Although head trauma, migraine, long-term bed rest, Ménière disease, viral labyrinthitis, and upper respiratory tract infections are believed to be predisposing factors, most cases of benign paroxysmal positional vertigo are idiopathic. Ear surgery is another cause, but after non-otologic surgery, attacks of benign paroxysmal positional vertigo are rare. We describe three cases of benign paroxysmal positional vertigo attacks after non-otologic surgery (one patient after a nasal septoplasty and two patients after dental endodontic treatment) and discuss the pathophysiological mechanism of benign paroxysmal positional vertigo seen after non-otologic surgery, its diagnosis and treatment.

  8. Pavlov's position toward American behaviorism.

    PubMed

    Windholz, G

    1983-10-01

    Pavlov's development of the conditional reflex theory coincided with the rise of American behaviorism. Substituting an objective physiology for a subjective psychology, Pavlov saw in the rise of American behaviorism a clear confirmation of his method and theory. But in the early 1930s, Lashley attacked Pavlov's theory of specific cerebral localization of function, proposing instead the concept of an internal cerebral organization; Guthrie objected to Pavlov's centralist interpretation of conditioning, proposing instead a peripheralist interpretation; while Hull challenged Pavlov's theory of sleep and hypnosis as the manifestations of inhibition. Pavlov replied with critiques of Lashley's, Guthrie's, and Hull's views, and, convinced that Lashley and Guthrie misunderstood his position, repeated his method's and theory's basic propositions. Yet, Pavlov never gave up the expectation that American behaviorism would accept his conditional reflex theory and saw in Hunter's 1932 statements a support of his assumptions.

  9. The Role of Education in an Historically Challenging and Politically Complex Environment: The Response of Public Universities to the September 11 Attacks

    ERIC Educational Resources Information Center

    Khan, Nigar J.

    2012-01-01

    The dissertation critically analyzes the response of a major research public university to the attacks of 9/11 in order to gain a deeper understanding of public universities' stance on the relevance of Middle East studies, particularly in the context of the serious and far-reaching impact of 9/11. The absence of an articulated position of the…

  10. Targeted attack on networks coupled by connectivity and dependency links

    NASA Astrophysics Data System (ADS)

    Du, Ruijin; Dong, Gaogao; Tian, Lixin; Liu, Runran

    2016-05-01

    Coupled systems used to increase capacity were shown beneficial as long as it does not open pathways to cascades. Previous studies on the robustness of coupled networks except for interdependent networks are almost the cases of random attack. Many challenges remain exist in targeted-attack problem of coupled networks. Since nodes within coupled networks show different functions for each network, this paper both analytically and numerically analyzed the robustness of coupled networks under three types of targeted attacking strategies, including attacking on nodes by considering internal and external degree, internal degree only, and external degree only. For coupled network with both interdependent and interconnected links, all degree distributions of intra- and inter-connectivity links are Poissonian, we find the system undergoes from second to first order phase transition as coupling strength q increases. The fraction of nodes in the giant component P∞ at stable state, the critical phase transition threshold pc (first order threshold pcI and second order threshold pcII), and the critical point (pc ,qc) separating the first and second order phase transitions are analytically obtained for three types of attacking strategies with attacking probability parameter α = 0 , 1. We also find the system becomes more vulnerable as the average degree of intra-links k ¯ or inter-links K ¯ decreases. Therefore, the minimum average degrees k¯min and K¯min to maintain the system stable are obtained for the case of α = 0 , 1. Moreover, we discussed three typical cases of coupled networks, interdependent networks (K ¯ = 0), interacting networks (q = 0) and bipartite network (k = 0, q = 0), the analytical expressions of P∞, pc and (pc ,qc) (only for interdependent) are given respectively. Besides, we study the equivalence relations between interdependent networks and coupled networks with connectivity and dependency links for the same pc. The results imply that we can

  11. Distinction between MOG antibody-positive and AQP4 antibody-positive NMO spectrum disorders

    PubMed Central

    Sato, Douglas Kazutoshi; Callegaro, Dagoberto; Lana-Peixoto, Marco Aurelio; Waters, Patrick J.; Jorge, Frederico M. de Haidar; Takahashi, Toshiyuki; Nakashima, Ichiro; Apostolos-Pereira, Samira Luisa; Talim, Natalia; Simm, Renata Faria; Lino, Angelina Maria Martins; Misu, Tatsuro; Leite, Maria Isabel; Aoki, Masashi

    2014-01-01

    Objective: To evaluate clinical features among patients with neuromyelitis optica spectrum disorders (NMOSD) who have myelin oligodendrocyte glycoprotein (MOG) antibodies, aquaporin-4 (AQP4) antibodies, or seronegativity for both antibodies. Methods: Sera from patients diagnosed with NMOSD in 1 of 3 centers (2 sites in Brazil and 1 site in Japan) were tested for MOG and AQP4 antibodies using cell-based assays with live transfected cells. Results: Among the 215 patients with NMOSD, 7.4% (16/215) were positive for MOG antibodies and 64.7% (139/215) were positive for AQP4 antibodies. No patients were positive for both antibodies. Patients with MOG antibodies represented 21.1% (16/76) of the patients negative for AQP4 antibodies. Compared with patients with AQP4 antibodies or patients who were seronegative, patients with MOG antibodies were more frequently male, had a more restricted phenotype (optic nerve more than spinal cord), more frequently had bilateral simultaneous optic neuritis, more often had a single attack, had spinal cord lesions distributed in the lower portion of the spinal cord, and usually demonstrated better functional recovery after an attack. Conclusions: Patients with NMOSD with MOG antibodies have distinct clinical features, fewer attacks, and better recovery than patients with AQP4 antibodies or patients seronegative for both antibodies. PMID:24415568

  12. Rheumatoid Arthritis When Your Immune System Attacks Your Body | NIH MedlinePlus the Magazine

    MedlinePlus

    ... Understanding Rheumatoid Arthritis (RA) Rheumatoid Arthritis When Your Immune System Attacks Your Body Past Issues / Summer 2014 Table ... disease, which means the arthritis results from your immune system attacking your body's own tissues. The course of ...

  13. Are Omega-3s Linked to Lower Risk for Fatal Heart Attack?

    MedlinePlus

    ... Omega-3s Linked to Lower Risk for Fatal Heart Attack? These vital nutrients are found in seafood, nuts ... these people, nearly 8,000 suffered a first heart attack over time, which resulted in 2,781 deaths. ...

  14. Lupus: When the Body Attacks Itself | NIH MedlinePlus the Magazine

    MedlinePlus

    ... of this page please turn JavaScript on. Feature: Lupus Lupus: When the Body Attacks Itself Past Issues / Spring 2014 Table of Contents fast facts 1 Lupus occurs when the body's immune system attacks the ...

  15. 3 CFR - Continuation of the National Emergency With Respect to Certain Terrorist Attacks

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... to Certain Terrorist Attacks Presidential Documents Other Presidential Documents Notice of September 10, 2009 Continuation of the National Emergency With Respect to Certain Terrorist Attacks Consistent... national emergency declared on September 14, 2001, in Proclamation 7463, with respect to the...

  16. Talk With Your Health Care Provider About Taking Aspirin to Prevent Heart Attack

    MedlinePlus

    ... q What are my chances of having a heart attack? q Would I benefit from taking aspirin? q ... Health Care Provider About Taking Aspirin to Prevent Heart Attacks Did you know that aspirin can be an ...

  17. Can You Recognize a Heart Attack or Stroke? What To Do When Every Moment Counts

    MedlinePlus

    ... our exit disclaimer . Subscribe Can You Recognize a Heart Attack or Stroke? What To Do When Every Moment ... When it comes to life-threatening conditions like heart attack or stroke, every minute counts. Get to know ...

  18. Aspirin for Reducing Your Risk of Heart Attack and Stroke: Know the Facts

    MedlinePlus

    ... of Aspirin Aspirin for Reducing Your Risk of Heart Attack and Stroke: Know the Facts Share Tweet Linkedin ... example, using aspirin to lower the risk of heart attack and clot-related strokes. In these cases, the ...

  19. Heart Failure After Heart Attack Tied to Cancer Risk in Study

    MedlinePlus

    ... gov/news/fullstory_159804.html Heart Failure After Heart Attack Tied to Cancer Risk in Study Preliminary finding ... News) -- People who develop heart failure after a heart attack may also face a higher risk of cancer, ...

  20. Analysis and visualization of large complex attack graphs for networks security

    NASA Astrophysics Data System (ADS)

    Chen, Hongda; Chen, Genshe; Blasch, Erik; Kruger, Martin; Sityar, Irma

    2007-04-01

    In this paper, we have proposed a comprehensive and innovative approach for analysis and visualization of large complex multi-step cyber attack graphs. As an automated tool for cyber attack detection, prediction, and visualization, the newly proposed method transforms large quantities of network security data into real-time actionable intelligence, which can be used to (1) provide guidance on network hardening to prevent attacks, (2) perform real-time attack event correlation during active attacks, and (3) formulate post-attack responses. We show that it is possible to visualize the complex graphs, including all possible network attack paths while still keeping complexity manageable. The proposed analysis and visualization tool provides an efficient and effective solution for predicting potential attacks upon observed intrusion evidence, as well as interactive multi-resolution views such that an analyst can first obtain high-level overviews quickly, and then drill down to specific details.

  1. High Doses of Fish Oil Might Help Healing After Heart Attack

    MedlinePlus

    ... gov/news/fullstory_160178.html High Doses of Fish Oil Might Help Healing After Heart Attack Study ... Heart attack patients who took high doses of fish oil supplements for six months showed improved heart ...

  2. Distributed Detection of Wormhole Attacks in Wireless Sensor Networks

    NASA Astrophysics Data System (ADS)

    de Graaf, Rennie; Hegazy, Islam; Horton, Jeffrey; Safavi-Naini, Reihaneh

    Sensors in a wireless sensor network depend on their neighbours to route their messages. Yet, routing protocols in wireless sensor network are vulnerable to different types of attacks. In this paper, we consider the wormhole attack in which the adversary diverts traffic from one part of the network to another part by introducing a low cost tunnel between the two parts. We introduce a distributed intrusion detection system that monitors the communication in the network and propose a criterion for the placement of intrusion detection nodes. The intrusion detection system searches for violations of that criterion to detect wormholes of length above a certain minimum value. We evaluate the effectiveness of our system in a simulated environment. The experiments show that our system can detect 100% of the wormholes that are beyond the communication range of the intrusion detection nodes. Finally, we discuss our results and show directions for future work.

  3. Analytic barrage attack model. Final report, January 1986-January 1989

    SciTech Connect

    St Ledger, J.W.; Naegeli, R.E.; Dowden, N.A.

    1989-01-01

    An analytic model is developed for a nuclear barrage attack, assuming weapons with no aiming error and a cookie-cutter damage function. The model is then extended with approximations for the effects of aiming error and distance damage sigma. The final result is a fast running model which calculates probability of damage for a barrage attack. The probability of damage is accurate to within seven percent or better, for weapon reliabilities of 50 to 100 percent, distance damage sigmas of 0.5 or less, and zero to very large circular error probabilities. FORTRAN 77 coding is included in the report for the analytic model and for a numerical model used to check the analytic results.

  4. Enhancing the potential for post-attack recovery. Final report

    SciTech Connect

    Not Available

    1986-12-01

    This document contains a series of six papers addressing different actions which, after implementation, could enhance the potential for post-attack recovery. It was produced as part of an overall project which FEMA-NP Directorate tasked to Titan Systems, Inc., in order to support the development of practicable plans and procedures for actions the federal government may take to enhance the probability of national survival and provide an improved basis for long-term recovery should the United States suffer a nuclear attack. The subjects of the paper are: Crisis Dispersal of Pharmaceuticals; Crisis Implementation of EMP Mitigation Procedures at Broadcast Stations; Crisis Dispersal of Petroleum Products; Crisis Dispersal of Transportation Assets; Peacetime EMP Mitigation of Petroleum Facilities; and Industry in Research and Publication of Survival Information.

  5. Fatal Injury Caused by a Ram (Ovis Aries) Attack.

    PubMed

    Škavić, Petar; Šprem, Nikica; Kostelić, Antun

    2015-09-01

    Animal-inflicted injuries to humans are a major public health problem around the world resulting in great morbidity, money loss, and mortality. They are related to wild and domestic animals alike. Animals can cause injuries by various mechanisms--biting, stinging, crushing, goring, stomping, butting, kicking, pecking, etc. We present a case of a ram's attack with fatal consequences. A 4-year-old, 120 kg jezersko-solčava breed ram with prior history of aggressive behavior inflicted multiple injuries to his 83-year-old owner, who died in the hospital a few hours later due to severe blunt force injuries sustained in the attack. The autopsy revealed the cause of death to be multiple injuries of the thorax and the head. Sheep, even though they are not considered aggressive or large farm animals such as cattle and horses, can inflict serious injuries with devastating results. PMID:26258770

  6. Applying the Principles of Homicide by Heart Attack.

    PubMed

    Hlavaty, Leigh; Sung, LokMan

    2016-06-01

    Homicide by heart attack is a well-established model in forensic pathology that describes death elicited during or immediately after a criminal act where a threat or fear of physical injury is present. After its introduction nearly 4 decades ago, the principle has undergone a handful of modifications but still maintains its core concepts. All cases of this nature during a 20-year period at the Wayne County Medical Examiner's Office were compared and contrasted for demographics, circumstances and scene investigation, and autopsy and toxicology findings. Of the cases fulfilling the previously established criteria for homicide by heart attack, more than 80% displayed significant changes because of hypertension. This finding coincides with the high prevalence of hypertension in our urban population and highlights the significance of this disease. Also present were minor external and internal injuries in select cases, which reinforce the understanding that physical contact between the decedent and assailant does not preclude this diagnosis. PMID:27049661

  7. Delayed attacks of malaria in visitors to the tropics.

    PubMed

    Horstmann, P

    1973-08-25

    Out of 80 Danish college students and their teachers visiting the Middle East, West Pakistan, and India by bus in two four-month journeys during the summer and autumn of 1971, six individuals developed an apparently first attack of vivax malaria within seven to nine months after their return to Denmark. No cases of malaria were seen in the group during the journeys. Prophylaxis with chloroquine (Resochin) was strictly observed when visiting the areas in which malaria is endemic.All cases responded rapidly and completely to a full course of treatment with chloroquine. The most probable cause of the delay of the clinical manifestations is drug prophylaxis, which can prevent a clinical attack but not always eradicate the parasite. PMID:4580023

  8. Study of aerodynamic technology for VSTOL fighter attack aircraft

    NASA Technical Reports Server (NTRS)

    Burhans, W., Jr.; Crafta, V. J., Jr.; Dannenhoffer, N.; Dellamura, F. A.; Krepski, R. E.

    1978-01-01

    Vertical short takeoff aircraft capability, supersonic dash capability, and transonic agility were investigated for the development of Fighter/attack aircraft to be accommodated on ships smaller than present aircraft carriers. Topics covered include: (1) description of viable V/STOL fighter/attack configuration (a high wing, close-coupled canard, twin-engine, control configured aircraft) which meets or exceeds specified levels of vehicle performance; (2) estimates of vehicle aerodynamic characteristics and the methodology utilized to generate them; (3) description of propulsion system characteristics and vehicle mass properties; (4) identification of areas of aerodynamic uncertainty; and (5) a test program to investigate the areas of aerodynamic uncertainty in the conventional flight mode.

  9. Cerebrospinal Fluid Aquaporin-4 Antibody Levels in Neuromyelitis Optica Attacks

    PubMed Central

    Sato, Douglas Kazutoshi; Callegaro, Dagoberto; de Haidar Jorge, Frederico M; Nakashima, Ichiro; Nishiyama, Shuhei; Takahashi, Toshiyuki; Simm, Renata Faria; Apostolos-Pereira, Samira Luisa; Misu, Tatsuro; Steinman, Lawrence; Aoki, Masashi; Fujihara, Kazuo

    2014-01-01

    To elucidate immunopathogenetic roles of aquaporin-4 antibodies in the cerebrospinal fluid (CSF) of neuromyelitis optica spectrum disorders (NMOSD), we analyzed aquaporin-4 antibody titers, cellular and inflammatory markers in the CSF collected from 11 aquaporin-4 antibody seropositive patients. The CSF aquaporin-4 antibody levels during attacks (but not in sera) closely correlated with pleocytosis, inflammatory cytokines including interleukin-6 that can regulate antibody-producing plasmablasts, and glial fibrillary acidic protein levels in the CSF. The amount of aquaporin-4 antibodies present in the central nervous system may have therapeutic implications, as it is associated with astrocyte injury and inflammatory responses during NMOSD attacks. Ann Neurol 2014;76:305–309 PMID:24977390

  10. [From inducers of panic attack to neurobiology of panic disorder].

    PubMed

    Bourin, M

    1996-12-01

    Various provocative agents, including sodium lactate, carbon dioxide (CO2), caffeine, yohimbine and cholecystokinin (CCK), have been utilized as panicogenics in studies on healthy volunteers as well as in panic disorder patients. Most provocative agents are lacking in specificity, limiting their use in identifying neurotransmitter systems involved in panic attacks. CCK appears to offer several advantages over other challenge strategies since it is a putative neurotransmitter in the CNS, with its own neuronal pathways and receptors, and reliably provokes panic attacks in a dose-dependent manner. It is important to clarify the relationships between CCK and other neurotransmitter systems in order to further understand the neurobiology of panic disorder. The possible roles of some of these neurotransmitters in panic disorder are discussed in this review.

  11. Aerodynamics of slender finned bodies at large angles of attack

    NASA Technical Reports Server (NTRS)

    Agnone, A. M.; Zakkay, V.; Tory, E.; Stallings, R.

    1977-01-01

    In certain missions finned missiles perform slewing maneuvers. Here, large angles of attack are attained. Experimental data needed to understand the aerodynamics of such vehicles are presented. The purpose of this investigation was to study the interaction of the body flow field with that produced by the fins and the resulting effects on the aerodynamic forces and moments. The experiments were conducted at a nominal Mach number of 2.7 and angles of attack from 0 to 50 deg, with two different models. The tests were performed in a range of Reynolds number from 1.5 x 10 to the 6th to 4 x 10 to the 7th per foot (to cover both the laminar and fully turbulent regimes.) Several fin roll angles were investigated. Static pressures on both body and fin surfaces are reported.

  12. Pivotable strakes for high angle of attack control

    NASA Technical Reports Server (NTRS)

    Bobbitt, P. J.; Foughner, J. T., Jr.

    1985-01-01

    A series of pivotable strakes have been tested in combination with a 44-deg swept wing to determine their ability to provide pitch control at high angles of attack. The tests were carried out in the Langley 7 X 10-Foot High-Speed tunnel at nominal Mach numbers of 0.3 to 0.4. A total of five strakes with various aspects ratios and shapes were tested at negative deflection angles of 5, 10, 15, and 20 deg through an angle of attack range up to approximately 50 deg. In addition, a cranked delta wing with 70-deg sweep was tested with two different pivotable apex flaps. This paper shows lift, drag and moment data for the complete configurations as well as for the separate contributions of the strakes and fuselage nose which are mounted on a second balance. Generally, strake deflection was found to have a significant effect on moment while lift/drag changed very little.

  13. Rational self-directed hypnotherapy: a treatment for panic attacks.

    PubMed

    Der, D F; Lewington, P

    1990-01-01

    A single-subject research design was employed to assess the efficacy of rational self-directed hypnotherapy in the treatment of panic attacks. Presenting symptoms were acute fear, dizziness, constricted throat, upset stomach, loss of appetite, loss of weight, insomnia, fear of doctors, and fear of returning to work. Treatment lasted 13 weeks plus a 2-week baseline and posttherapy period and a 6-month follow-up. Objective measurements (MMPI, TSCS, POMS) and self-report assessments (physiological symptoms and a subjective stress inventory) were implemented. Using hypnosis and guided imagery, the subject reviewed critical incidents identifying self-defeating components within a cognitive paradigm, revising and rehearsing these incidents. Results showed an increased sense of control, improved self-concept, elimination of pathological symptoms, and cessation of panic attacks.

  14. Forebody tangential blowing for control at high angles of attack

    NASA Technical Reports Server (NTRS)

    Kroo, I.; Rock, S.; Roberts, L.

    1991-01-01

    A feasibility study to determine if the use of tangential leading edge blowing over the forebody could produce effective and practical control of the F-18 HARV aircraft at high angles of attack was conducted. A simplified model of the F-18 configuration using a vortex-lattice model was developed to obtain a better understanding of basic aerodynamic coupling effects and the influence of forebody circulation on lifting surface behavior. The effect of tangential blowing was estimated using existing wind tunnel data on normal forebody blowing and analytical studies of tangential blowing over conical forebodies. Incorporation of forebody blowing into the flight control system was investigated by adding this additional yaw control and sideforce generating actuator into the existing F-18 HARV simulation model. A control law was synthesized using LQG design methods that would schedule blowing rates as a function of vehicle sideslip, angle of attack, and roll and yaw rates.

  15. Robustness of networks against propagating attacks under vaccination strategies

    NASA Astrophysics Data System (ADS)

    Hasegawa, Takehisa; Masuda, Naoki

    2011-09-01

    We study the effect of vaccination on the robustness of networks against propagating attacks that obey the susceptible-infected-removed model. By extending the generating function formalism developed by Newman (2005 Phys. Rev. Lett. 95 108701), we analytically determine the robustness of networks that depends on the vaccination parameters. We consider the random defense where nodes are vaccinated randomly and the degree-based defense where hubs are preferentially vaccinated. We show that, when vaccines are inefficient, the random graph is more robust against propagating attacks than the scale-free network. When vaccines are relatively efficient, the scale-free network with the degree-based defense is more robust than the random graph with the random defense and the scale-free network with the random defense.

  16. Applying the Principles of Homicide by Heart Attack.

    PubMed

    Hlavaty, Leigh; Sung, LokMan

    2016-06-01

    Homicide by heart attack is a well-established model in forensic pathology that describes death elicited during or immediately after a criminal act where a threat or fear of physical injury is present. After its introduction nearly 4 decades ago, the principle has undergone a handful of modifications but still maintains its core concepts. All cases of this nature during a 20-year period at the Wayne County Medical Examiner's Office were compared and contrasted for demographics, circumstances and scene investigation, and autopsy and toxicology findings. Of the cases fulfilling the previously established criteria for homicide by heart attack, more than 80% displayed significant changes because of hypertension. This finding coincides with the high prevalence of hypertension in our urban population and highlights the significance of this disease. Also present were minor external and internal injuries in select cases, which reinforce the understanding that physical contact between the decedent and assailant does not preclude this diagnosis.

  17. High-angle-of-attack aerodynamics - Lessons learned

    NASA Technical Reports Server (NTRS)

    Chambers, J. R.

    1986-01-01

    Recently, the military and civil technical communities have undertaken numerous studies of the high angle-of-attack aerodynamic characteristics of advanced airplane and missile configurations. The method of approach and the design methodology employed have necessarily been experimental and exploratory in nature, due to the complex nature of separated flows. However, despite the relatively poor definition of many of the key aerodynamic phenomena involved for high-alpha conditions, some generic guidelines for design consideration have been identified. The present paper summarizes some of the more important lessons learned in the area of high angle-of-attack aerodynamics with examples of a number of key concepts and with particular emphasis on high-alpha stability and control characteristics of high performance aircraft. Topics covered in the discussion include the impact of design evolution, forebody flows, control of separated flows, configuration effects, aerodynamic controls, wind-tunnel flight correlation, and recent NASA research activities.

  18. Human North American river otter (Lontra canadensis) attack.

    PubMed

    Potter, Tiffany M; Hanna, Jill A; Freer, Luanne

    2007-01-01

    As a result of the successful restoration and conservation programs deployed by state and federal agencies, populations of the North American river otter (Lontra canadensis) are increasing in many states. Recreational activities such as swimming, boating, and fishing increase the likelihood of human interactions with this charismatic, nonendangered mustelid. Otters tend to avoid areas of high human activity, occur at low population densities, and in some habitats in the United States have not recovered from population declines. Therefore, interactions with humans are rare, and aggressive encounters by otters are even less frequent. We report a recent, aggressive, and unprovoked attack that was followed by immediate medical treatment, including postexposure rabies prophylaxis, extensive suturing, and subsequent reconstructive surgery. We discuss river otter biology, the prevalence of diseases in wild populations of river otter, and otter attacks on humans and their treatment.

  19. Screening for generalized anxiety disorder symptoms in the wake of terrorist attacks: a study in primary care.

    PubMed

    Ghafoori, Bita; Neria, Yuval; Gameroff, Marc J; Olfson, Mark; Lantigua, Rafael; Shea, Steven; Weissman, Myrna M

    2009-06-01

    Little is known about the mental health impact of terrorism beyond posttraumatic stress disorder (PTSD) and depression. The associations between exposure to the September 11, 2001 (9/11) attacks in New York City and generalized anxiety disorder (GAD) symptoms were examined in a sample of 929 primary care patients. After controlling for PTSD, depression, panic and substance use disorders, and pre-9/11 trauma, patients who screened positive (vs. negative) for GAD symptoms were roughly twice as likely to report having a loved one at the 9/11 disaster site, twice as likely to know someone who was killed by the attacks, and twice as likely to know someone who was involved with the rescue/recovery efforts after the disaster. Implications for treatment and future research are discussed.

  20. Cerebral correlates of heart rate variations during a spontaneous panic attack in the fMRI scanner.

    PubMed

    Spiegelhalder, Kai; Hornyak, Magdolna; Kyle, Simon David; Paul, Dominik; Blechert, Jens; Seifritz, Erich; Hennig, Jürgen; Tebartz van Elst, Ludger; Riemann, Dieter; Feige, Bernd

    2009-12-01

    We report the first published case study of a suddenly occurring panic attack in a patient with no prior history of panic disorder during combined functional magnetic resonance imaging (fMRI, 1.5 Tesla) and electrocardiogram (ECG) recording. The single case was a 46-year-old woman who developed a panic attack near the planned end of the fMRI acquisition session, which therefore had to be aborted. Correlational analysis of heart rate fluctuations and fMRI data revealed a significant negative association in the left middle temporal gyrus. Additionally, regions-of-interest (ROI) analyses indicated significant positive associations in the left amygdala, and trends towards significance in the right amygdala and left insula.

  1. Screening for Generalized Anxiety Disorder Symptoms in the Wake of Terrorist Attacks: A Study in Primary Care

    PubMed Central

    Ghafoori, Bita; Neria, Yuval; Gameroff, Marc J.; Olfson, Mark; Lantigua, Rafael; Shea, Steven; Weissman, Myrna M.

    2013-01-01

    Little is known about the mental health impact of terrorism beyond posttraumatic stress disorder (PTSD) and depression. The associations between exposure to the September 11, 2001 (9/11) attacks in New York City and generalized anxiety disorder (GAD) symptoms were examined in a sample of 929 primary care patients. After controlling for PTSD, depression, panic and substance use disorders, and pre-9/11 trauma, patients who screened positive (vs. negative) for GAD symptoms were roughly twice as likely to report having a loved one at the 9/11 disaster site, twice as likely to know someone who was killed by the attacks, and twice as likely to know someone who was involved with the rescue/recovery efforts after the disaster. Implications for treatment and future research are discussed. PMID:19475656

  2. Mental health issues in disasters and terrorist attacks.

    PubMed

    Schlenger, William E; Jernigan, Nancy E

    2003-01-01

    Recent events make clear that those living in the United States are at risk of exposure to a variety of potentially traumatic events, ranging from sniper and terrorist attacks to a variety of natural disasters. This paper provides a broad overview of the most common psychological reactions that can be expected in the aftermath of such events, how primary care practitioners can identify such reactions in their patients, and actions those practitioners might take.

  3. Animal attack: an unusual case of multiple trauma in childhood.

    PubMed

    O'Grady, E; Doyle, M; Fitzgerald, C W R; Mortell, A; Murray, D

    2014-01-01

    A 2½ year old girl attended our facility following attack by a tapir at a city zoo. She sustained multiple injuries including a forearm laceration and multiple perforating wounds to her abdominal wall. She had several procedures, including bowel resection, performed under the care of the General Paediatric Surgery and Plastic Surgery teams and was treated with a course of IV antibiotics. She recovered well and to date has suffered no long-term adverse outcome. PMID:25551902

  4. A Latex Metabolite Benefits Plant Fitness under Root Herbivore Attack.

    PubMed

    Huber, Meret; Epping, Janina; Schulze Gronover, Christian; Fricke, Julia; Aziz, Zohra; Brillatz, Théo; Swyers, Michael; Köllner, Tobias G; Vogel, Heiko; Hammerbacher, Almuth; Triebwasser-Freese, Daniella; Robert, Christelle A M; Verhoeven, Koen; Preite, Veronica; Gershenzon, Jonathan; Erb, Matthias

    2016-01-01

    Plants produce large amounts of secondary metabolites in their shoots and roots and store them in specialized secretory structures. Although secondary metabolites and their secretory structures are commonly assumed to have a defensive function, evidence that they benefit plant fitness under herbivore attack is scarce, especially below ground. Here, we tested whether latex secondary metabolites produced by the common dandelion (Taraxacum officinale agg.) decrease the performance of its major native insect root herbivore, the larvae of the common cockchafer (Melolontha melolontha), and benefit plant vegetative and reproductive fitness under M. melolontha attack. Across 17 T. officinale genotypes screened by gas and liquid chromatography, latex concentrations of the sesquiterpene lactone taraxinic acid β-D-glucopyranosyl ester (TA-G) were negatively associated with M. melolontha larval growth. Adding purified TA-G to artificial diet at ecologically relevant concentrations reduced larval feeding. Silencing the germacrene A synthase ToGAS1, an enzyme that was identified to catalyze the first committed step of TA-G biosynthesis, resulted in a 90% reduction of TA-G levels and a pronounced increase in M. melolontha feeding. Transgenic, TA-G-deficient lines were preferred by M. melolontha and suffered three times more root biomass reduction than control lines. In a common garden experiment involving over 2,000 T. officinale individuals belonging to 17 different genotypes, high TA-G concentrations were associated with the maintenance of high vegetative and reproductive fitness under M. melolontha attack. Taken together, our study demonstrates that a latex secondary metabolite benefits plants under herbivore attack, a result that provides a mechanistic framework for root herbivore driven natural selection and evolution of plant defenses below ground. PMID:26731567

  5. Device-independent security of quantum cryptography against collective attacks.

    PubMed

    Acín, Antonio; Brunner, Nicolas; Gisin, Nicolas; Massar, Serge; Pironio, Stefano; Scarani, Valerio

    2007-06-01

    We present the optimal collective attack on a quantum key distribution protocol in the "device-independent" security scenario, where no assumptions are made about the way the quantum key distribution devices work or on what quantum system they operate. Our main result is a tight bound on the Holevo information between one of the authorized parties and the eavesdropper, as a function of the amount of violation of a Bell-type inequality.

  6. Posttraumatic stress disorder among survivors of a kamikaze attack.

    PubMed

    Chara, P J; Chara, K A

    2001-12-01

    26 sailors who survived a Kamikaze attack during the battle for Okinawa in World War II were given two adapted forms of the Posttraumatic Stress Disorder Checklist-Civilian to assess the psychological reactions they had to the sinking of their ship. Depending on the assessment criteria used, their responses indicated significant stress reactions ranging from 8.3% to 44% of the sample. The findings provide evidence that a single combat experience can have lifelong, averse psychological effects.

  7. Paraplegia due to Spinal Epidermoid Cyst Rupture at Asthma Attack

    PubMed Central

    Kim, Kweon Young; Kang, Jung Hun; Choi, Dae Woo; Lee, Min Hong

    2013-01-01

    Spinal epidermoid cyst is less than 1% of the entire spinal cord tumor and a rare tumor. It is a slowly proliferating benign tumor and can be a result of either congenital or acquired factors. In particular, reports of acute paraplegia due to spinal epidermoid cyst rupture are very rare. Since authors experienced paraplegia resulting from congenital spinal epidermoid cyst rupture during an asthma attack, it is reported with a review of literature. PMID:23705125

  8. A Latex Metabolite Benefits Plant Fitness under Root Herbivore Attack.

    PubMed

    Huber, Meret; Epping, Janina; Schulze Gronover, Christian; Fricke, Julia; Aziz, Zohra; Brillatz, Théo; Swyers, Michael; Köllner, Tobias G; Vogel, Heiko; Hammerbacher, Almuth; Triebwasser-Freese, Daniella; Robert, Christelle A M; Verhoeven, Koen; Preite, Veronica; Gershenzon, Jonathan; Erb, Matthias

    2016-01-01

    Plants produce large amounts of secondary metabolites in their shoots and roots and store them in specialized secretory structures. Although secondary metabolites and their secretory structures are commonly assumed to have a defensive function, evidence that they benefit plant fitness under herbivore attack is scarce, especially below ground. Here, we tested whether latex secondary metabolites produced by the common dandelion (Taraxacum officinale agg.) decrease the performance of its major native insect root herbivore, the larvae of the common cockchafer (Melolontha melolontha), and benefit plant vegetative and reproductive fitness under M. melolontha attack. Across 17 T. officinale genotypes screened by gas and liquid chromatography, latex concentrations of the sesquiterpene lactone taraxinic acid β-D-glucopyranosyl ester (TA-G) were negatively associated with M. melolontha larval growth. Adding purified TA-G to artificial diet at ecologically relevant concentrations reduced larval feeding. Silencing the germacrene A synthase ToGAS1, an enzyme that was identified to catalyze the first committed step of TA-G biosynthesis, resulted in a 90% reduction of TA-G levels and a pronounced increase in M. melolontha feeding. Transgenic, TA-G-deficient lines were preferred by M. melolontha and suffered three times more root biomass reduction than control lines. In a common garden experiment involving over 2,000 T. officinale individuals belonging to 17 different genotypes, high TA-G concentrations were associated with the maintenance of high vegetative and reproductive fitness under M. melolontha attack. Taken together, our study demonstrates that a latex secondary metabolite benefits plants under herbivore attack, a result that provides a mechanistic framework for root herbivore driven natural selection and evolution of plant defenses below ground.

  9. A Latex Metabolite Benefits Plant Fitness under Root Herbivore Attack

    PubMed Central

    Huber, Meret; Epping, Janina; Schulze Gronover, Christian; Fricke, Julia; Aziz, Zohra; Brillatz, Théo; Swyers, Michael; Köllner, Tobias G.; Vogel, Heiko; Hammerbacher, Almuth; Triebwasser-Freese, Daniella; Robert, Christelle A. M.; Verhoeven, Koen; Preite, Veronica; Gershenzon, Jonathan; Erb, Matthias

    2016-01-01

    Plants produce large amounts of secondary metabolites in their shoots and roots and store them in specialized secretory structures. Although secondary metabolites and their secretory structures are commonly assumed to have a defensive function, evidence that they benefit plant fitness under herbivore attack is scarce, especially below ground. Here, we tested whether latex secondary metabolites produced by the common dandelion (Taraxacum officinale agg.) decrease the performance of its major native insect root herbivore, the larvae of the common cockchafer (Melolontha melolontha), and benefit plant vegetative and reproductive fitness under M. melolontha attack. Across 17 T. officinale genotypes screened by gas and liquid chromatography, latex concentrations of the sesquiterpene lactone taraxinic acid β-D-glucopyranosyl ester (TA-G) were negatively associated with M. melolontha larval growth. Adding purified TA-G to artificial diet at ecologically relevant concentrations reduced larval feeding. Silencing the germacrene A synthase ToGAS1, an enzyme that was identified to catalyze the first committed step of TA-G biosynthesis, resulted in a 90% reduction of TA-G levels and a pronounced increase in M. melolontha feeding. Transgenic, TA-G-deficient lines were preferred by M. melolontha and suffered three times more root biomass reduction than control lines. In a common garden experiment involving over 2,000 T. officinale individuals belonging to 17 different genotypes, high TA-G concentrations were associated with the maintenance of high vegetative and reproductive fitness under M. melolontha attack. Taken together, our study demonstrates that a latex secondary metabolite benefits plants under herbivore attack, a result that provides a mechanistic framework for root herbivore driven natural selection and evolution of plant defenses below ground. PMID:26731567

  10. Use of outcomes to evaluate surveillance systems for bioterrorist attacks

    PubMed Central

    2010-01-01

    Background Syndromic surveillance systems can potentially be used to detect a bioterrorist attack earlier than traditional surveillance, by virtue of their near real-time analysis of relevant data. Receiver operator characteristic (ROC) curve analysis using the area under the curve (AUC) as a comparison metric has been recommended as a practical evaluation tool for syndromic surveillance systems, yet traditional ROC curves do not account for timeliness of detection or subsequent time-dependent health outcomes. Methods Using a decision-analytic approach, we predicted outcomes, measured in lives, quality adjusted life years (QALYs), and costs, for a series of simulated bioterrorist attacks. We then evaluated seven detection algorithms applied to syndromic surveillance data using outcomes-weighted ROC curves compared to simple ROC curves and timeliness-weighted ROC curves. We performed sensitivity analyses by varying the model inputs between best and worst case scenarios and by applying different methods of AUC calculation. Results The decision analytic model results indicate that if a surveillance system was successful in detecting an attack, and measures were immediately taken to deliver treatment to the population, the lives, QALYs and dollars lost could be reduced considerably. The ROC curve analysis shows that the incorporation of outcomes into the evaluation metric has an important effect on the apparent performance of the surveillance systems. The relative order of performance is also heavily dependent on the choice of AUC calculation method. Conclusions This study demonstrates the importance of accounting for mortality, morbidity and costs in the evaluation of syndromic surveillance systems. Incorporating these outcomes into the ROC curve analysis allows for more accurate identification of the optimal method for signaling a possible bioterrorist attack. In addition, the parameters used to construct an ROC curve should be given careful consideration. PMID

  11. Total decontamination cost of the anthrax letter attacks.

    PubMed

    Schmitt, Ketra; Zacchia, Nicholas A

    2012-03-01

    All of the costs associated with decontamination following the 2001 anthrax letter attacks were summarized, estimated, and aggregated based on existing literature and news media reports. A comprehensive list of all affected structures was compiled. Costs were analyzed by building class and decontamination type. Sampling costs and costs of worker relocation were also included. Our analysis indicates that the total cost associated with decontamination was about $320 million.

  12. Low aspect ratio wings at high angles of attack

    NASA Technical Reports Server (NTRS)

    Stallings, Robert L., Jr.

    1992-01-01

    A survey is conducted of the results of investigations into the flowfields and aerodynamic forces associated with low aspect ratio wings at high angles of attack. Attention is given to criteria for the cataloging of these flowfields, the phenomenon of vortex breakdown, with varying wing incidence and Mach number, and the effects of aspect ratio and compressibility. The planforms treated are of rectangular, clipped-delta, and strake-wing combination geometries. Extensive graphic representations of performance trends with varying parameters are furnished.

  13. Measurement of intergranular attack in stainless steel using ultrasonic energy

    DOEpatents

    Mott, Gerry; Attaar, Mustan; Rishel, Rick D.

    1989-08-08

    Ultrasonic test methods are used to measure the depth of intergranular attack (IGA) in a stainless steel specimen. The ultrasonic test methods include a pitch-catch surface wave technique and a through-wall pulse-echo technique. When used in combination, these techniques can establish the extent of IGA on both the front and back surfaces of a stainless steel specimen from measurements made on only one surface.

  14. Animal attack: an unusual case of multiple trauma in childhood.

    PubMed

    O'Grady, E; Doyle, M; Fitzgerald, C W R; Mortell, A; Murray, D

    2014-01-01

    A 2½ year old girl attended our facility following attack by a tapir at a city zoo. She sustained multiple injuries including a forearm laceration and multiple perforating wounds to her abdominal wall. She had several procedures, including bowel resection, performed under the care of the General Paediatric Surgery and Plastic Surgery teams and was treated with a course of IV antibiotics. She recovered well and to date has suffered no long-term adverse outcome.

  15. Trojan horse attacks on counterfactual quantum key distribution

    NASA Astrophysics Data System (ADS)

    Yang, Xiuqing; Wei, Kejin; Ma, Haiqiang; Sun, Shihai; Du, Yungang; Wu, Lingan

    2016-04-01

    There has been much interest in "counterfactual quantum cryptography" (T.-G. Noh, 2009 [10]). It seems that the counterfactual quantum key distribution protocol without any photon carrier through the quantum channel provides practical security advantages. However, we show that it is easy to break counterfactual quantum key distribution systems in practical situations. We introduce the two types of Trojan horse attacks that are available for the two-way protocol and become possible for practical counterfactual systems with our eavesdropping schemes.

  16. Longitudinal Aerodynamic Characteristics to Large Angles of Attack of a Cruciform Missile Configuration at a Mach Number of 2

    NASA Technical Reports Server (NTRS)

    Spahr, J. R.

    1954-01-01

    The lift, pitching-moment, and drag characteristics of a missile configuration having a body of fineness ratio 9.33 and a cruciform triangular wing and tail of aspect ratio 4 were measured at a Mach number of 1.99 and a Reynolds number of 6.0 million, based on the body length. The tests were performed through an angle-of-attack range of -5 deg to 28 deg to investigate the effects on the aerodynamic characteristics of roll angle, wing-tail interdigitation, wing deflection, and interference among the components (body, wing, and tail). Theoretical lift and moment characteristics of the configuration and its components were calculated by the use of existing theoretical methods which have been modified for application to high angles of attack, and these characteristics are compared with experiment. The lift and drag characteristics of all combinations of the body, wing, and tail were independent of roll angle throughout the angle-of-attack range. The pitching-moment characteristics of the body-wing and body-wing-tail combinations, however, were influenced significantly by the roll angle at large angles of attack (greater than 10 deg). A roll from 0 deg (one pair of wing panels horizontal) to 45 deg caused a forward shift in the center of pressure which was of the same magnitude for both of these combinations, indicating that this shift originated from body-wing interference effects. A favorable lift-interference effect (lift of the combination greater than the sum of the lifts of the components) and a rearward shift in the center of pressure from a position corresponding to that for the components occurred at small angles of attack when the body was combined with either the exposed wing or tail surfaces. These lift and center-of-pressure interference effects were gradually reduced to zero as the angle of attack was increased to large values. The effect of wing-tail interference, which influenced primarily the pitching-moment characteristics, is dependent on the distance

  17. Longitudinal Aerodynamic Characteristics to Large Angles of Attack of a Cruciform Missile Configuration at a Mach Number of 2

    NASA Technical Reports Server (NTRS)

    Spahr, J Richard

    1954-01-01

    The lift, pitching-moment, and drag characteristics of a missile configuration having a body of fineness ratio 9.33 and a cruciform triangular wing and tail of aspect ratio 4 were measured at a Mach number of 1.99 and a Reynolds number of 6.0 million, based on the body length. The tests were performed through an angle-of-attack range of -5 deg to 28 deg to investigate the effects on the aerodynamic characteristics of roll angle, wing-tail interdigitation, wing deflection, and interference among the components (body, wing, and tail). Theoretical lift and moment characteristics of the configuration and its components were calculated by the use of existing theoretical methods which have been modified for application to high angles of attack, and these characteristics are compared with experiment. The lift and drag characteristics of all combinations of the body, wing, and tail were independent of roll angle throughout the angle-of-attack range. The pitching-moment characteristics of the body-wing and body-wing- tail combinations, however, were influenced significantly by the roll angle at large angles of attack (greater than 10 deg). A roll from 0 deg (one pair of wing panels horizontal) to 45 deg caused a forward shift in the center of pressure which was of the same magnitude for both of these combinations, indicating that this shift originated from body-wing interference effects. A favorable lift - interference effect (lift of the combination greater than the sum of the lifts of the components) and a rearward shift in the center of pressure from a position corresponding to that for the components occurred at small angles of attack when the body was combined with either the exposed wing or tail surfaces. These lift and center-of-pressure interference effects were gradually reduced to zero as the angle of attack was increased to large values. The effect of wing-tail interference, which influenced primarily the pitching-moment characteristics, is dependent on the

  18. Malicious attacks on media authentication schemes based on invertible watermarks

    NASA Astrophysics Data System (ADS)

    Katzenbeisser, Stefan; Dittmann, Jana

    2004-06-01

    The increasing availability and distribution of multimedia technology has made the manipulation of digital images, videos or audio files easy. While this enables numerous new applications, a certain loss of trust in digital media can be observed. In general, there is no guarantee that a digital image "does not lie", i.e., that the image content was not altered. To counteract this risk, fragile watermarks were proposed to protect the integrity of digital multimedia objects. In high security applications, it is necessary to be able to reconstruct the original object out of the watermarked version. This can be achieved by the use of invertible watermarks. While traditional watermarking schemes introduce some small non-invertible distortion in the digital content, invertible watermarks can be completely removed from a watermarked work. In the past, the security of proposed image authentication schemes based on invertible watermarks was only analyzed using ad-hoc methods and neglected the possibility of malicious attacks, which aim at engineering a fake mark so that the attacked object appears to be genuine. In this paper, we characterize and analyze possible malicious attacks against watermark-based image authentication systems and explore the theoretical limits of previous constructions with respect to their security.

  19. Identifying optimal targets of network attack by belief propagation

    NASA Astrophysics Data System (ADS)

    Mugisha, Salomon; Zhou, Hai-Jun

    2016-07-01

    For a network formed by nodes and undirected links between pairs of nodes, the network optimal attack problem aims at deleting a minimum number of target nodes to break the network down into many small components. This problem is intrinsically related to the feedback vertex set problem that was successfully tackled by spin-glass theory and an associated belief propagation-guided decimation (BPD) algorithm [Zhou, Eur. Phys. J. B 86, 455 (2013), 10.1140/epjb/e2013-40690-1]. In the present work we apply the BPD algorithm (which has approximately linear time complexity) to the network optimal attack problem and demonstrate that it has much better performance than a recently proposed collective information algorithm [Morone and Makse, Nature 524, 65 (2015), 10.1038/nature14604] for different types of random networks and real-world network instances. The BPD-guided attack scheme often induces an abrupt collapse of the whole network, which may make it very difficult to defend.

  20. Bio-inspired diversity for increasing attacker workload

    NASA Astrophysics Data System (ADS)

    Kuhn, Stephen

    2014-05-01

    Much of the traffic in modern computer networks is conducted between clients and servers, rather than client-toclient. As a result, servers represent a high-value target for collection and analysis of network traffic. As they reside at a single network location (i.e. IP/MAC address) for long periods of time. Servers present a static target for surveillance, and a unique opportunity to observe the network traffic. Although servers present a heightened value for attackers, the security community as a whole has shifted more towards protecting clients in recent years leaving a gap in coverage. In addition, servers typically remain active on networks for years, potentially decades. This paper builds on previous work that demonstrated a proof of concept leveraging existing technology for increasing attacker workload. Here we present our clean slate approach to increasing attacker workload through a novel hypervisor and micro-kernel, utilizing next generation virtualization technology to create synthetic diversity of the server's presence including the hardware components.