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Sample records for acoustic countermeasures

  1. Acoustics

    Goodman, Jerry R.; Grosveld, Ferdinand

    2007-01-01

    The acoustics environment in space operations is important to maintain at manageable levels so that the crewperson can remain safe, functional, effective, and reasonably comfortable. High acoustic levels can produce temporary or permanent hearing loss, or cause other physiological symptoms such as auditory pain, headaches, discomfort, strain in the vocal cords, or fatigue. Noise is defined as undesirable sound. Excessive noise may result in psychological effects such as irritability, inability to concentrate, decrease in productivity, annoyance, errors in judgment, and distraction. A noisy environment can also result in the inability to sleep, or sleep well. Elevated noise levels can affect the ability to communicate, understand what is being said, hear what is going on in the environment, degrade crew performance and operations, and create habitability concerns. Superfluous noise emissions can also create the inability to hear alarms or other important auditory cues such as an equipment malfunctioning. Recent space flight experience, evaluations of the requirements in crew habitable areas, and lessons learned (Goodman 2003; Allen and Goodman 2003; Pilkinton 2003; Grosveld et al. 2003) show the importance of maintaining an acceptable acoustics environment. This is best accomplished by having a high-quality set of limits/requirements early in the program, the "designing in" of acoustics in the development of hardware and systems, and by monitoring, testing and verifying the levels to ensure that they are acceptable.

  2. Countermeasures and barriers

    In 1973 Haddon proposed ten strategies for reducing and avoiding damages based on a model of potential harmful energy transfer (Haddon, 1973). The strategies apply to a large variety of unwanted phenomena. Haddon's pioneering work on countermeasures has had a major influence on later thinking about safety. Considering its impact it is remarkable that the literature offers almost no discussions related to the theoretical foundations of Haddon's countermeasure strategies. The present report addresses a number of theoretical issues related to Haddon's countermeasure strategies, which are: 1) A reformulation and formalization of Haddon's countermeasure strategies. 2) An identification and description of some of the problems associated with the term 'barrier'. 3) Suggestions for a more precise terminology based on the causal structure of countermeasures. 4) Extending the scope of countermeasures to include sign-based countermeasures. (au)

  3. Countermeasures and barriers

    Petersen, Johannes [Oersted - DTU, Automation, Kgs. Lyngby (Denmark)

    2005-10-01

    In 1973 Haddon proposed ten strategies for reducing and avoiding damages based on a model of potential harmful energy transfer (Haddon, 1973). The strategies apply to a large variety of unwanted phenomena. Haddon's pioneering work on countermeasures has had a major influence on later thinking about safety. Considering its impact it is remarkable that the literature offers almost no discussions related to the theoretical foundations of Haddon's countermeasure strategies. The present report addresses a number of theoretical issues related to Haddon's countermeasure strategies, which are: 1) A reformulation and formalization of Haddon's countermeasure strategies. 2) An identification and description of some of the problems associated with the term 'barrier'. 3) Suggestions for a more precise terminology based on the causal structure of countermeasures. 4) Extending the scope of countermeasures to include sign-based countermeasures. (au)

  4. Adaptive network countermeasures.

    McClelland-Bane, Randy; Van Randwyk, Jamie A.; Carathimas, Anthony G.; Thomas, Eric D.

    2003-10-01

    This report describes the results of a two-year LDRD funded by the Differentiating Technologies investment area. The project investigated the use of countermeasures in protecting computer networks as well as how current countermeasures could be changed in order to adapt with both evolving networks and evolving attackers. The work involved collaboration between Sandia employees and students in the Sandia - California Center for Cyber Defenders (CCD) program. We include an explanation of the need for adaptive countermeasures, a description of the architecture we designed to provide adaptive countermeasures, and evaluations of the system.

  5. Pyrotechnic countermeasures: II. Advanced aerial infrared countermeasures

    Koch, Ernst-Christian [Diehl BGT Defence GmbH and Co. KG, Fischbachstrasse 16, D-90552 Roethenbach a. d. Pegnitz (Germany)

    2006-02-15

    This paper discusses the technology of advanced aerial infrared countermeasures and related work disclosed in the unclassified literature. Missile-seeker head counter-countermeasures include spectral discrimination, kinematical discrimination, rise-time discrimination, UV/VIS discrimination and area temperature matching. Advanced flare payloads designed to counter dual color seekers contain selectively emitting compositions based primarily on high carbon fuels and perchlorates. Other advanced payloads consist of low temperature emitters like pyrophoric metal foils and gasless pyrotechnic compositions like Fe/KClO{sub 4}. The optimization of black body flares, still considered essential to a successful countermeasure solution, make use of new fuels based on e.g. meta-stable alloys and nanometer-sized powders as well as high energetic oxidizers. Kinematic flares today use combined propellant and infrared grains. 116 references from the public domain are given. For part I see Propellants, Explos., Pyrotech. 2001, 26, 3. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  6. Countermeasures in Switzerland

    Concerning countermeasures in Switzerland, part of them are tested every year in exercises. An operational emergency management in the EPZ (Emergency Planning Zones) is a condition for operating a NPP (Nuclear Power Plant) in Switzerland. The NPP operators have to pay special installations and preparations, automatic monitoring network in the inner EPZ and iodine tablets for the EPZ population. Countermeasures concerning EPZ, sheltering hospitals, farmers are summarized in this document. It also presents the use of iodine tablets based on the ICRP's recommendations (International Commission Radiological Protection), and the implementation of evacuation plans, public information or exercises organised by the EOR (Emergency Organisation Radioactivity). (TEC). 4 refs., 1 fig

  7. Countermeasure in forest ecosystems

    It is suggested that for economic reasons local governments in the areas of Sweden which are most contaminated from the Chernobyl major nuclear accident, as well as the forest companies, should have an interest in countermeasures for reducing the Cesium-137 acitivity concentrations in moose. This viewpoint is explained. Potassium fertilizing experiments were carried out on rocky ground with a shallow layer of soil or at a boggy area with peat soil. By fertilizing the heater, eaten by moose Cesium-137 activity could be reduced by 50%. The mean value was 11,000 Bq kg-1. The decrease occuring within 2-3 months also showed that there is an exchange of radiocesium in heather plants. There was found a large seasonal variation in the Cesium-137 activity concentration in roe-deer, so another countermeasure was to change the time of the hunting season from August to May where cesium activity in the meat was lowest. Deer were also given salt licks with Geisesalt (resulting in 50% reduction) and cesiumbinder in their fodder (as yet no reliable results) in furhter attempts to reduce cesium activity in their meat. Results are presented in the form of graphs. (AB)

  8. Countermeasures implemented in intensive agriculture

    The wide application of countermeasures in agriculture at different times after the Chernobyl accident provided an opportunity to estimate the most efficient means of reducing radionuclide transfer through the chain soil-plant-animal-man. The choice of countermeasures against the background of traditional practices was governed by a variety of factors, including the composition of the radioactive fallout, the soil types, land usage, the time elapsed since the accident and the economics. The efficiency of the various countermeasures was assessed in terms of both reduction of individual dose in the contaminated areas and of the collective dose. The estimation of the various countermeasures comparative efficiency is presented, their impact on individual doses reduction and the contribution reduction of produce produced in the contaminated area into the collective dose of the population is shown

  9. Countermeasures in radiation emergencies

    ICRP Publication 60 (1990) contains recommendations on two radiological situations: (i) Human activities that add radiation exposure to that which people normally incur due to background radiation, or that increases the likelihood of their incurring exposure are termed PRACTICES. Here the occurrences of the exposure are foreseen and can be limited by control of source and by application of the ICRP system of dose limitation and (ii) The human activities that seek to reduce the existing radiation exposure, or the existing likelihood of incurring exposure which is not part of a controlled practice are termed INTERVENTIONS. Here the source of exposure is not subject to control, for example, in accident situations so that any subsequent exposure can be limited only by some form of INTERVENTION. The relevant general recommendations on intervention are that the countermeasures forming a program of intervention, which always have some disadvantage, should be justified in the sense that they should do more good than harm. Their form, scale and duration should be then optimised so as to maximise the net benefit

  10. Communication Acoustics

    Blauert, Jens

    Communication Acoustics deals with the fundamentals of those areas of acoustics which are related to modern communication technologies. Due to the advent of digital signal processing and recording in acoustics, these areas have enjoyed an enormous upswing during the last 4 decades. The book...... the book a source of valuable information for those who want to improve or refresh their knowledge in the field of communication acoustics - and to work their way deeper into it. Due to its interdisciplinary character Communication Acoustics is bound to attract readers from many different areas, such as......: acoustics, cognitive science, speech science, and communication technology....

  11. Network radar countermeasure systems integrating radar and radar countermeasures

    Jiang, Qiuxi

    2016-01-01

    This is the very first book to present the network radar countermeasure system. It explains in detail the systematic concept of combining radar and radar countermeasures from the perspective of the information acquisition of target location, the optimization of the reconnaissance and detection, the integrated attack of the signals and facilities, and technological and legal developments concerning the networked system. It achieves the integration of the initiative and passivity, detection and jamming. The book explains how the system locates targets, completes target identification, tracks targets and compiles the data.

  12. Acoustic Neuroma

    An acoustic neuroma is a benign tumor that develops on the nerve that connects the ear to the brain. ... can press against the brain, becoming life-threatening. Acoustic neuroma can be difficult to diagnose, because the ...

  13. Acoustic Neuroma

    An acoustic neuroma is a benign tumor that develops on the nerve that connects the ear to the brain. The tumor ... press against the brain, becoming life-threatening. Acoustic neuroma can be difficult to diagnose, because the symptoms ...

  14. XQuery Injection Attack and Countermeasures

    谭玉森

    2014-01-01

    As a database that allows data to be stored in XML format, XML database suffers from some similar attacks as traditional relational database does. These attacks include injection attack by XQuey function in application software. These include BaseX, eXist and MarkLogic. In order to defeat these attacks, countermeasures are proposed.

  15. A gravity loading countermeasure skinsuit

    Waldie, James M.; Newman, Dava J.

    2011-04-01

    Despite the use of several countermeasures, significant physiological deconditioning still occurs during long duration spaceflight. Bone loss - primarily due to the absence of loading in microgravity - is perhaps the greatest challenge to resolve. This paper describes a conceptual Gravity Loading Countermeasure Skinsuit (GLCS) that induces loading on the body to mimic standing and - when integrated with other countermeasures - exercising on Earth. Comfort, mobility and other operational issues were explored during a pilot study carried out in parabolic flight for prototype suits worn by three subjects. Compared to the 1- or 2-stage Russian Pingvin Suits, the elastic mesh of the GLCS can create a loading regime that gradually increases in hundreds of stages from the shoulders to the feet, thereby reproducing the weight-bearing regime normally imparted by gravity with much higher resolution. Modelling shows that the skinsuit requires less than 10 mmHg (1.3 kPa) of compression for three subjects of varied gender, height and mass. Negligible mobility restriction and excellent comfort properties were found during the parabolic flights, which suggests that crewmembers should be able to work normally, exercise or sleep while wearing the suit. The suit may also serve as a practical 1 g harness for exercise countermeasures and vibration applications to improve dynamic loading.

  16. Acoustic Issues in Human Spaceflight

    Clark, Jonathan B.

    2001-01-01

    NASA is concerned about acute effect of sound on crew performance on International Space Station (ISS), and is developing strategies to assess and reduce acute, chronic, and delayed effects of sound. High noise levels can cause headaches, irritation, fatigue, impaired sleep, headache, and tinnitus and have resulted in an inability to hear alarms. Speech intelligibility may be more impaired for crew understanding non-native language in a noisy environment. No hearing loss occurred, but significant effects on crew performance and communication occurred. Permanent Threshold Shifts (PTS) have not been observed in the US shuttle program. Russian specification for noise in spacecraft is 60 dBA (awake) and 50 dBA (asleep) while the U.S. noise specification on ISS is NC 50 (awake) and NC 40 (asleep) with a 85 dBA hazard limit. Background noise levels of ISS modules have measured 56-69 dBA. Treadmill exercise operations measure 77 dBA. Alarms are required to be 20 dBA above ambient. Hearing protection is recommended when noise exceeds 60 dB 24 hour Leq. Countermeasures include hearing protection and design/ engineering controls. Advanced composite materials with excellent low frequency attenuation properties could be applied as a barrier protection around noisy equipment, or used on personal protective equipment worn by the crew. Hearing protection countermeasures include foam ear inserts, passive muff headsets, and active noise reduction headsets. Oto-acoustic emissions (OAE) could be used to monitor effectiveness of hearing protection countermeasures and tailor hearing protection countermeasures to individual crewmembers. Micro-gravity, vibration, toxic fumes, air quality/composition, stress, temperature, physical exertion or some combination of the above factors may have interacted with moderate long-term noise exposure to cause significant hearing loss. Longitudinal studies will need to address what co-morbidity factors, such as radiation, toxicology, microgravity

  17. Acoustic cloaking and transformation acoustics

    In this review, we give a brief introduction to the application of the new technique of transformation acoustics, which draws on a correspondence between coordinate transformation and material properties. The technique is formulated for both acoustic waves and linear liquid surface waves. Some interesting conceptual devices can be designed for manipulating acoustic waves. For example, we can design acoustic cloaks that make an object invisible to acoustic waves, and the cloak can either encompass or lie outside the object to be concealed. Transformation acoustics, as an analog of transformation optics, can go beyond invisibility cloaking. As an illustration for manipulating linear liquid surface waves, we show that a liquid wave rotator can be designed and fabricated to rotate the wave front. The acoustic transformation media require acoustic materials which are anisotropic and inhomogeneous. Such materials are difficult to find in nature. However, composite materials with embedded sub-wavelength resonators can in principle be made and such 'acoustic metamaterials' can exhibit nearly arbitrary values of effective density and modulus tensors to satisfy the demanding material requirements in transformation acoustics. We introduce resonant sonic materials and Helmholtz resonators as examples of acoustic metamaterials that exhibit resonant behaviour in effective density and effective modulus. (topical review)

  18. Acoustic cloaking and transformation acoustics

    Chen Huanyang [School of Physical Science and Technology, Soochow University, Suzhou, Jiangsu 215006 (China); Chan, C T, E-mail: kenyon@ust.h, E-mail: phchan@ust.h [Department of Physics and the William Mong Institute of NanoScience and Technology, The Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong)

    2010-03-24

    In this review, we give a brief introduction to the application of the new technique of transformation acoustics, which draws on a correspondence between coordinate transformation and material properties. The technique is formulated for both acoustic waves and linear liquid surface waves. Some interesting conceptual devices can be designed for manipulating acoustic waves. For example, we can design acoustic cloaks that make an object invisible to acoustic waves, and the cloak can either encompass or lie outside the object to be concealed. Transformation acoustics, as an analog of transformation optics, can go beyond invisibility cloaking. As an illustration for manipulating linear liquid surface waves, we show that a liquid wave rotator can be designed and fabricated to rotate the wave front. The acoustic transformation media require acoustic materials which are anisotropic and inhomogeneous. Such materials are difficult to find in nature. However, composite materials with embedded sub-wavelength resonators can in principle be made and such 'acoustic metamaterials' can exhibit nearly arbitrary values of effective density and modulus tensors to satisfy the demanding material requirements in transformation acoustics. We introduce resonant sonic materials and Helmholtz resonators as examples of acoustic metamaterials that exhibit resonant behaviour in effective density and effective modulus. (topical review)

  19. 78 FR 20664 - 2013 Medical Countermeasures Initiative Regulatory Science Symposium

    2013-04-05

    ... HUMAN SERVICES Food and Drug Administration 2013 Medical Countermeasures Initiative Regulatory Science... medical countermeasure development, highlight work on regulatory science as it applies to the development... Administration (FDA) is announcing the following meeting: 2013 Medical Countermeasures initiative...

  20. Acoustical Imaging

    Litniewski, Jerzy; Kujawska, Tamara; 31st International Symposium on Acoustical Imaging

    2012-01-01

    The International Symposium on Acoustical Imaging is a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. This interdisciplinary Symposium has been taking place continuously since 1968. In the course of the years the proceedings volumes in the Acoustical Imaging Series have become a reference for cutting-edge research in the field. In 2011 the 31st International Symposium on Acoustical Imaging was held in Warsaw, Poland, April 10-13. Offering both a broad perspective on the state-of-the-art as well as  in-depth research contributions by the specialists in the field, this Volume 31 in the Series contains an excellent collection of papers in six major categories: Biological and Medical Imaging Physics and Mathematics of Acoustical Imaging Acoustic Microscopy Transducers and Arrays Nondestructive Evaluation and Industrial Applications Underwater Imaging

  1. Contemporary Radiation Countermeasure (Review Paper

    Vivek N. Patel

    2011-02-01

    Full Text Available Radiation countermeasures have been investigated for decades, but the search for ideal protective agents for use prior to or after irradiation still continues. This review focuses on agents that have demonstrated as potential as in vivo countermeasure agents and may subsequently be effectively used in human beings. Such agents are categorised as radioprotectors, radiation mitigators, or therapeutic agents dependening upon their time of administration. These protective or mitigating agents are designed to reduce inadvertent damage to normal tissue caused by radiation. These interventions function via various mechanisms of action ranging from modulating signalling pathways to inhibiting cell death, cytokines, and growth factor. Many agents demonstrated promising results in murine models and are being tested in human beings. Amifostine, and curcumin have shown radioprotection, while genistein, palifermin, and halofuginone have been shown to alleviate the side effects in patients undergoing radiotherapy. Though these compounds show some promise as radiation countermeasure agents, there are several associated limitations and the search for perfect agents still continues.Defence Science Journal, 2011, 61(2, pp.138-145, DOI:http://dx.doi.org/10.14429/dsj.61.834

  2. Radiation acoustics

    Lyamshev, Leonid M

    2004-01-01

    Radiation acoustics is a developing field lying at the intersection of acoustics, high-energy physics, nuclear physics, and condensed matter physics. Radiation Acoustics is among the first books to address this promising field of study, and the first to collect all of the most significant results achieved since research in this area began in earnest in the 1970s.The book begins by reviewing the data on elementary particles, absorption of penetrating radiation in a substance, and the mechanisms of acoustic radiation excitation. The next seven chapters present a theoretical treatment of thermoradiation sound generation in condensed media under the action of modulated penetrating radiation and radiation pulses. The author explores particular features of the acoustic fields of moving thermoradiation sound sources, sound excitation by single high-energy particles, and the efficiency and optimal conditions of thermoradiation sound generation. Experimental results follow the theoretical discussions, and these clearl...

  3. The Biomechanics of Exercise Countermeasures

    Cavanagh, Peter R.; Arnold, Steven; Derr, Janice; Sharkey, Neil; Wu, Ge

    1999-01-01

    The Penn State Zero-gravity Simulator (PSZS) is a device developed by the Center for Locomotion Studies (CELOS) to enable ground studies of exercise countermeasures for the bone loss that has been shown to occur during long-term exposure to zero gravity (0G). The PSZS simulates 0G exercise by providing a suspension system that holds an individual in a horizontal (supine) position above the floor in order to enable exercise on a wall-mounted treadmill. Due to this orientation, exercise performed in the PSZS is free of the force of -ravity in the direction that would normally contribute to ground reaction forces. In order for movements to be more similar to those in 0G, a constant force suspension of each segment (equal to the segment weight) is provided regardless of limb position. During the preliminary development of the PSZS, CELOS researchers also designed an optional gravity-replacement simulation feature for the PSZS. This feature was a prototype tethering system that consisted of a spring tension system to pull an exercising individual toward the treadmill. The immediate application of the tethering system was to be the provision of gravity-replacement loading so that exercise in 0G- and 1G-loading conditions could be compared, and the PSZS could then be used to evaluate exercise countermeasures for bone loss during space flight. This tethering system would also be a model for the further refinement of gravity-replacement systems provided for astronaut usage while performing prescribed exercise countermeasures for bone loss during long-term space flights.

  4. Acoustical Imaging

    Akiyama, Iwaki

    2009-01-01

    The 29th International Symposium on Acoustical Imaging was held in Shonan Village, Kanagawa, Japan, April 15-18, 2007. This interdisciplinary Symposium has been taking place every two years since 1968 and forms a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. In the course of the years the volumes in the Acoustical Imaging Series have developed and become well-known and appreciated reference works. Offering both a broad perspective on the state-of-the-art in the field as well as an in-depth look at its leading edge research, this Volume 29 in the Series contains again an excellent collection of seventy papers presented in nine major categories: Strain Imaging Biological and Medical Applications Acoustic Microscopy Non-Destructive Evaluation and Industrial Applications Components and Systems Geophysics and Underwater Imaging Physics and Mathematics Medical Image Analysis FDTD method and Other Numerical Simulations Audience Researcher...

  5. Acoustic telemetry

    National Oceanic and Atmospheric Administration, Department of Commerce — To determine movements of green turtles in the nearshore foraging areas, we deployed acoustic tags and determined their movements through active and passive...

  6. Acoustics Research

    National Oceanic and Atmospheric Administration, Department of Commerce — Fisheries acoustics data are collected from more than 200 sea-days each year aboard the FRV DELAWARE II and FRV ALBATROSS IV (decommissioned) and the FSV Henry B....

  7. Battlefield acoustics

    Damarla, Thyagaraju

    2015-01-01

    This book presents all aspects of situational awareness in a battlefield using acoustic signals. It starts by presenting the science behind understanding and interpretation of sound signals. The book then goes on to provide various signal processing techniques used in acoustics to find the direction of sound source, localize gunfire, track vehicles, and detect people. The necessary mathematical background and various classification and fusion techniques are presented. The book contains majority of the things one would need to process acoustic signals for all aspects of situational awareness in one location. The book also presents array theory, which is pivotal in finding the direction of arrival of acoustic signals. In addition, the book presents techniques to fuse the information from multiple homogeneous/heterogeneous sensors for better detection. MATLAB code is provided for majority of the real application, which is a valuable resource in not only understanding the theory but readers, can also use the code...

  8. High-rate wireless data communications: An underwater acoustic communications framework at the physical layer

    Anthony G. Bessios

    1996-01-01

    the signal represents; 2 estimation of some parameter θˆ associated with the received signal (i.e. range, depth, bearing angle, etc.; 3 classification and source identification; 4 dynamics tracking; 5 navigation (collision avoidance and terminal guidance; 6 countermeasures; and 7 communications. The focus of this paper is acoustic communications.

  9. The NIAID Radiation Countermeasures Program business model.

    Hafer, Nathaniel; Maidment, Bert W; Hatchett, Richard J

    2010-12-01

    The National Institute of Allergy and Infectious Diseases (NIAID) Radiation/Nuclear Medical Countermeasures Development Program has developed an integrated approach to providing the resources and expertise required for the research, discovery, and development of radiation/nuclear medical countermeasures (MCMs). These resources and services lower the opportunity costs and reduce the barriers to entry for companies interested in working in this area and accelerate translational progress by providing goal-oriented stewardship of promising projects. In many ways, the radiation countermeasures program functions as a "virtual pharmaceutical firm," coordinating the early and mid-stage development of a wide array of radiation/nuclear MCMs. This commentary describes the radiation countermeasures program and discusses a novel business model that has facilitated product development partnerships between the federal government and academic investigators and biopharmaceutical companies. PMID:21142762

  10. Fault attacks on two software countermeasures

    Moro, Nicolas; Heydemann, Karine; Dehbaoui, Amine; Robisson, Bruno; Encrenaz, Emmanuelle

    2014-01-01

    Short version of the article "Experimental evaluation of two software countermeasures against fault attacks" presented at the 2014 IEEE Symposium on Hardware-Oriented Security and Trust (HOST) in May 2014.

  11. Acoustic emission

    This paper is related to our activities on acoustic emission (A.E.). The work is made with different materials: metals and fibre reinforced plastics. At present, acoustic emission transducers are being developed for low and high temperature. A test to detect electrical discharges in electrical transformers was performed. Our experience in industrial tests to detect cracks or failures in tanks or tubes is also described. The use of A.E. for leak detection is considered. Works on pattern recognition of A.E. signals are also being performed. (Author)

  12. Practical hacking techniques and countermeasures

    Spivey, Mark D

    2006-01-01

    Examining computer security from the hacker''s perspective, Practical Hacking Techniques and Countermeasures employs virtual computers to illustrate how an attack is executed, including the script, compilation, and results. It provides detailed screen shots in each lab for the reader to follow along in a step-by-step process in order to duplicate and understand how the attack works. It enables experimenting with hacking techniques without fear of corrupting computers or violating any laws.Written in a lab manual style, the book begins with the installation of the VMware® Workstation product and guides the users through detailed hacking labs enabling them to experience what a hacker actually does during an attack. It covers social engineering techniques, footprinting techniques, and scanning tools. Later chapters examine spoofing techniques, sniffing techniques, password cracking, and attack tools. Identifying wireless attacks, the book also explores Trojans, Man-in-the-Middle (MTM) attacks, and Denial of S...

  13. Sensor-guided threat countermeasure system

    Stuart, Brent C.; Hackel, Lloyd A.; Hermann, Mark R.; Armstrong, James P.

    2012-12-25

    A countermeasure system for use by a target to protect against an incoming sensor-guided threat. The system includes a laser system for producing a broadband beam and means for directing the broadband beam from the target to the threat. The countermeasure system comprises the steps of producing a broadband beam and directing the broad band beam from the target to blind or confuse the incoming sensor-guided threat.

  14. Sensorial countermeasures for vestibular spatial disorientation.

    Paillard, Aurore C; Quarck, Gaëlle; Denise, Pierre

    2014-05-01

    Spatial disorientation is defined as an erroneous body orientation perceived by pilots during flights. Limits of the vestibular system provoke frequent spatial disorientation mishaps. Although vestibular spatial disorientation is experienced frequently in aviation, there is no intuitive countermeasure against spatial disorientation mishaps to date. The aim of this review is to describe the current sensorial countermeasures and to examine future leads in sensorial ergonomics for vestibular spatial disorientation. This work reviews: 1) the visual ergonomics, 2) the vestibular countermeasures, 3) the auditory displays, 4) the somatosensory countermeasures, and, finally, 5) the multisensory displays. This review emphasizes the positive aspects of auditory and somatosensory countermeasures as well as multisensory devices. Even if some aspects such as sensory conflict and motion sickness need to be assessed, these countermeasures should be taken into consideration for ergonomics work in the future. However, a recent development in aviation might offer new and better perspectives: unmanned aerial vehicles. Unmanned aerial vehicles aim to go beyond the physiological boundaries of human sensorial systems and would allow for coping with spatial disorientation and motion sickness. Even if research is necessary to improve the interaction between machines and humans, this recent development might be incredibly useful for decreasing or even stopping vestibular spatial disorientation. PMID:24834571

  15. 77 FR 21785 - Medical Countermeasures Initiative Regulatory Science Symposium

    2012-04-11

    ... HUMAN SERVICES Food and Drug Administration Medical Countermeasures Initiative Regulatory Science... Administration (FDA) is announcing the following meeting: Medical Countermeasures Initiative Regulatory Science... development, highlight work on regulatory science as it applies to the development and advancement of...

  16. Position paper on active countermeasures for computer networks.

    Van Randwyk, Jamie A.

    2003-07-01

    Computer security professionals have used passive network countermeasures for several years in order to secure computer networks. Passive countermeasures such as firewalls and intrusion detection systems are effective but their use alone is not enough to protect a network. Active countermeasures offer new ways of protecting a computer network. Corporations and government entities should adopt active network countermeasures as a means of protecting their computer networks.

  17. Acoustic lenses

    Acoustic lenses focus ultrasound to produce pencil-like beams with reduced near fields. When fitted to conventional (flat-faced) transducers, such lenses greatly improve the ability to detect and size defects. This paper describes a program developed to design acoustic lenses for use in immersion or contact inspection, using normal or angle beam mode with flat or curved targets. Lens surfaces are circular in geometry to facilitate machining. For normal beam inspection of flat plate, spherical or cylindrical lenses are used. For angle beam or curved surface inspections, a compound lens is required to correct for the extra induced aberration. Such a lens is aspherical with one radius of curvature in the plane of incidence, and a different radius of curvature in the plane perpendicular to the incident plane. The resultant beam profile (i.e., location of the acoustic focus, beam diameter, 6 dB working range) depends on the degree of focusing and the transducer used. The operating frequency and bandwidth can be affected by the instrumentation used. Theoretical and measured beam profiles are in good agreement. Various applications, from zone focusing used for defect sizing in thick plate, to line focusing for pipe weld inspection, are discussed

  18. NASA Exercise Physiology and Countermeasures Project Overview

    Loerch, Linda; Ploutz-Snyder, Lori

    2009-01-01

    Efficient exercise countermeasures are necessary to offset or minimize spaceflight-induced deconditioning and to maximize crew performance of mission tasks. These countermeasure protocols should use the fewest crew and vehicle resources. NASA s Exercise Physiology and Countermeasures (ExPC) Project works to identify, collect, interpret, and summarize evidence that results in effective exercise countermeasure protocols which protect crew health and performance during International Space Station (ISS) and future exploration-class missions. The ExPC and NASA s Human Research Program are sponsoring multiple studies to evaluate and improve the efficacy of spaceflight exercise countermeasures. First, the Project will measure maximal aerobic capacity (VO2max) during cycle ergometry before, during, and after ISS missions. Second, the Project is sponsoring an evaluation of a new prototype harness that offers improved comfort and increased loading during treadmill operations. Third, the Functional Tasks Test protocol will map performance of anticipated lunar mission tasks with physiologic systems before and after short and long-duration spaceflight, to target system contributions and the tailoring of exercise protocols to maximize performance. In addition to these studies that are actively enrolling crewmember participants, the ExPC is planning new studies that include an evaluation of a higher-intensity/lower-volume exercise countermeasure protocol aboard the ISS using the Advanced Resistive Exercise Device and second-generation treadmill, studies that evaluate bone loading during spaceflight exercise, and ground-based studies that focus on fitness for duty standards required to complete lunar mission tasks and for which exercise protocols need to protect. Summaries of these current and future studies and strategies will be provided to international colleagues for knowledge sharing and possible collaboration.

  19. Risk Analysis and Security Countermeasure Selection

    Norman, Thomas L

    2009-01-01

    Explains how to evaluate the appropriateness of security countermeasures, from a cost-effectiveness perspective. This title guides readers from basic principles to complex processes in a step-by-step fashion, evaluating DHS-approved risk assessment methods, including CARVER, API/NPRA, RAMCAP, and various Sandia methodologies

  20. Northeast Asian Dynamism: Ten Top Impediments & Countermeasures

    Lambert, Bruce Henry

    2002-01-01

    Northeast Asia has had trouble developing regional interaction, cooperation and market synergies; this paper summarizes key impediments and proposes various countermeasures. Suggestions include improvements in administrative transparency and property law, building on EU and ASEAN organizing experiences through benchmarking, and offering free or low-cost land to boost migration & investment. A bilingual annotated appendix lists over fifty multilateral coordinating initiatives & key organizatio...

  1. Optical countermeasures against CLOS weapon systems

    Toet, Alexander; Benoist, Koen W.; van Lingen, Joost N. J.; Schleijpen, H. Ric M. A.

    2013-10-01

    There are many weapon systems in which a human operator acquires a target, tracks it and designates it. Optical countermeasures against this type of systems deny the operator the possibility to fulfill this visual task. We describe the different effects that result from stimulation of the human visual system with high intensity (visible) light, and the associated potential operational impact. Of practical use are flash blindness, where an intense flash of light produces a temporary "blind-spot" in (part of) the visual field, flicker distraction, where strong intensity and/or color changes at a discomfortable frequency are produced, and disability glare where a source of light leads to contrast reduction. Hence there are three possibilities to disrupt the visual task of an operator with optical countermeasures such as flares or lasers or a combination of these; namely, by an intense flash of light, by an annoying light flicker or by a glare source. A variety of flares for this purpose is now available or under development: high intensity flash flares, continuous burning flares or strobe flares which have an oscillating intensity. The use of flare arrays seems particularly promising as an optical countermeasure. Lasers are particularly suited to interfere with human vision, because they can easily be varied in intensity, color and size, but they have to be directed at the (human) target, and issues like pointing and eye-safety have to be taken into account. Here we discuss the design issues and the operational impact of optical countermeasures against human operators.

  2. Threats and countermeasures for network security

    Denning, Peter J.

    1991-01-01

    In the late 1980's, the traditional threat of anonymous break-ins to networked computers was joined by viruses and worms, multiplicative surrogates that carry out the bidding of their authors. Technologies for authentication and secrecy, supplemented by good management practices, are the principal countermeasures. Four articles on these subjects are presented.

  3. Modelling of agricultural countermeasures in RODOS

    Predictions of the effects of agricultural countermeasures taken to reduce doses are an important part of the decision making process following an accidental release of radioactive material into the environment. Models have been developed for this purpose within the EC decision support system, RODOS. This paper describes the methodology used and the development of databases on the practicability of agricultural countermeasures for use in such a system. Within RODOS a wide range of potentially practicable countermeasures are considered and endpoints related to their imposition are calculated such that the economic and health impacts can be evaluated. The methodology utilizes time-dependent information from a food chain model, together with databases of empirical transfer parameters and effectiveness factors for the various countermeasures. Measures implemented in both the immediate aftermath of an accident and in the longer term are considered. A database containing robust representative data that can be applied to relatively large areas is currently implemented in RODOS. The database utilizes information from the Chernobyl accident compiled within an EC initiated collaborative project (JSP1) by institutes in the Ukraine, Russia, Belarus and the NRPB. Detailed data for four settlements in these countries have been compiled and compared with the robust database. The use of detailed databases at a local level in the three countries, where account is taken of factors such as soil type, is also discussed. The applicability of agricultural countermeasures implemented in the Ukraine, Russia and Belarus following the Chernobyl accident to agricultural systems in the UK has been evaluated and the appropriateness of the compiled databases for wider application is discussed

  4. Acoustic hemostasis

    Crum, L.; Andrew, M.; Bailey, M.; Beach, K.; Brayman, A.; Curra, F.; Kaczkowski, P.; Kargl, S.; Martin, R.; Vaezy, S.

    2003-04-01

    Over the past several years, the Center for Industrial and Medical Ultrasound (CIMU) at the Applied Physics Laboratory in the University of Washington has undertaken a broad research program in the general area of High Intensity Focused Ultrasound (HIFU). Our principal emphasis has been on the use of HIFU to induce hemostasis; in particular, CIMU has sought to develop a small, lightweight, portable device that would use ultrasound for both imaging and therapy. Such a technology is needed because nearly 50% of combat casualty mortality results from exsanguinations, or uncontrolled bleeding. A similar percentage occurs for civilian death due to trauma. In this general review, a presentation of the general problem will be given, as well as our recent approaches to the development of an image-guided, transcutaneous, acoustic hemostasis device. [Work supported in part by the USAMRMC, ONR and the NIH.

  5. Acoustic telemetry.

    Drumheller, Douglas Schaeffer; Kuszmaul, Scott S.

    2003-08-01

    Broadcasting messages through the earth is a daunting task. Indeed, broadcasting a normal telephone conversion through the earth by wireless means is impossible with todays technology. Most of us don't care, but some do. Industries that drill into the earth need wireless communication to broadcast navigation parameters. This allows them to steer their drill bits. They also need information about the natural formation that they are drilling. Measurements of parameters such as pressure, temperature, and gamma radiation levels can tell them if they have found a valuable resource such as a geothermal reservoir or a stratum bearing natural gas. Wireless communication methods are available to the drilling industry. Information is broadcast via either pressure waves in the drilling fluid or electromagnetic waves in the earth and well tubing. Data transmission can only travel one way at rates around a few baud. Given that normal Internet telephone modems operate near 20,000 baud, these data rates are truly very slow. Moreover, communication is often interrupted or permanently blocked by drilling conditions or natural formation properties. Here we describe a tool that communicates with stress waves traveling through the steel drill pipe and production tubing in the well. It's based on an old idea called Acoustic Telemetry. But what we present here is more than an idea. This tool exists, it's drilled several wells, and it works. Currently, it's the first and only acoustic telemetry tool that can withstand the drilling environment. It broadcasts one way over a limited range at much faster rates than existing methods, but we also know how build a system that can communicate both up and down wells of indefinite length.

  6. Acoustic Neuroma Educational Video

    Full Text Available Educational Video Home What is an AN What is an Acoustic Neuroma? Identifying an AN Symptoms Acoustic Neuroma Keywords Educational Video ... for pre- and post-treatment acoustic neuroma patients. Home What is an AN What is an Acoustic ...

  7. Use of acoustic vortices in acoustic levitation

    Cutanda Henriquez, Vicente; Santillan, Arturo Orozco; Juhl, Peter Møller

    2009-01-01

    Acoustic fields are known to exert forces on the surfaces of objects. These forces are noticeable if the sound pressure is sufficiently high. Two phenomena where acoustic forces are relevant are: i) acoustic levitation, where strong standing waves can hold small objects at certain positions...... of acoustical vortices uses an efficient numerical implementation based on the superposition of two orthogonal sound fields with a delay of 90° between them. It is shown that acoustic levitation and the use of acoustic vortices can be combined to manipulate objects in an efficient and controlled manner without......, counterbalancing their weight, and ii) acoustic vortices, spinning sound fields that can impinge angular momentum and cause rotation of objects. In this contribution, both force-creating sound fields are studied by means of numerical simulations. The Boundary Element Method is employed to this end. The simulation...

  8. Acoustic dispersive prism

    Hussein Esfahlani; Sami Karkar; Herve Lissek; Mosig, Juan R.

    2016-01-01

    The optical dispersive prism is a well-studied element, which allows separating white light into its constituent spectral colors, and stands in nature as water droplets. In analogy to this definition, the acoustic dispersive prism should be an acoustic device with capability of splitting a broadband acoustic wave into its constituent Fourier components. However, due to the acoustical nature of materials as well as the design and fabrication difficulties, there is neither any natural acoustic ...

  9. Acoustic Neurinomas

    Mohammad Faraji Rad

    2011-01-01

    Full Text Available Acoustic neuromas (AN are schwann cell-derived tumors that commonly arise from the vestibular portion of the eighth cranial nerve also known as vestibular schwannoma(VS causes unilateral hearing loss, tinnitus, vertigo and unsteadiness. In many cases, the tumor size may remain unchanged for many years following diagnosis, which is typically made by MRI. In the majority of cases the tumor is small, leaving the clinician and patient with the options of either serial scanning or active treatment by gamma knife radiosurgery (GKR or microneurosurgery. Despite the vast number of published treatment reports, comparative studies are few. The predominant clinical endpoints of AN treatment include tumor control, facial nerve function and hearing preservation. Less focus has been put on symptom relief and health-related quality of life (QOL. It is uncertain if treating a small tumor leaves the patient with a better chance of obtaining relief from future hearing loss, vertigo or tinnitus than by observing it without treatment.   In this paper we review the literature for the natural course, the treatment alternatives and the results of AN. Finally, we present our experience with a management strategy applied for more than 30 years.

  10. Acoustic Spatiality

    Brandon LaBelle

    2012-06-01

    Full Text Available Experiences of listening can be appreciated as intensely relational, bringing us into contact with surrounding events, bodies and things. Given that sound propagates and expands outwardly, as a set of oscillations from a particular source, listening carries with it a sensual intensity, whereby auditory phenomena deliver intrusive and disruptive as well as soothing and assuring experiences. The physicality characteristic of sound suggests a deeply impressionistic, locational "knowledge structure" – that is, the ways in which listening affords processes of exchange, of being in the world, and from which we extend ourselves. Sound, as physical energy reflecting and absorbing into the materiality around us, and even one's self, provides a rich platform for understanding place and emplacement. Sound is always already a trace of location.Such features of auditory experience give suggestion for what I may call an acoustical paradigm – how sound sets in motion not only the material world but also the flows of the imagination, lending to forces of signification and social structure, and figuring us in relation to each other. The relationality of sound brings us into a steady web of interferences, each of which announces the promise or problematic of being somewhere.

  11. Springer Handbook of Acoustics

    Rossing, Thomas D

    2007-01-01

    Acoustics, the science of sound, has developed into a broad interdisciplinary field encompassing the academic disciplines of physics, engineering, psychology, speech, audiology, music, architecture, physiology, neuroscience, and others. The Springer Handbook of Acoustics is an unparalleled modern handbook reflecting this richly interdisciplinary nature edited by one of the acknowledged masters in the field, Thomas Rossing. Researchers and students benefit from the comprehensive contents spanning: animal acoustics including infrasound and ultrasound, environmental noise control, music and human speech and singing, physiological and psychological acoustics, architectural acoustics, physical and engineering acoustics, signal processing, medical acoustics, and ocean acoustics. This handbook reviews the most important areas of acoustics, with emphasis on current research. The authors of the various chapters are all experts in their fields. Each chapter is richly illustrated with figures and tables. The latest rese...

  12. Responsive acoustic surfaces

    Peters, Brady; Tamke, Martin; Nielsen, Stig Anton;

    2011-01-01

    Acoustic performance is defined by the parameter of reverberation time; however, this does not capture the acoustic experience in some types of open plan spaces. As many working and learning activities now take place in open plan spaces, it is important to be able to understand and design for the...... acoustic conditions of these spaces. This paper describes an experimental research project that studied the design processes necessary to design for sound. A responsive acoustic surface was designed, fabricated and tested. This acoustic surface was designed to create specific sonic effects. The design was...... simulated using custom integrated acoustic software and also using Odeon acoustic analysis software. The research demonstrates a method for designing space- and sound-defining surfaces, defines the concept of acoustic subspace, and suggests some new parameters for defining acoustic subspaces....

  13. [The countermeasure system for extended space flights].

    Kozlovskaia, I B; Pestov, I D; Egorov, A D

    2008-01-01

    The article summarizes the results of developing countermeasures by the team of winners of the USSR state prize under the leadership of academician O.G. Gazenko, and ensuing investigations at the Institute for Biomedical Problems. The system of countermeasures against the debilitating developments in cosmonaut's organism first developed in Russia ensured successful completion of long-term SF (64 to 438 days) aboard the Salyut and Mir orbital stations. The system incorporates exercises on the treadmill and veloergometer, axial body loading in suit Pinguin, application of negative pressure on the lower part of the body vacuum suit Chibis and several others. The system proved high efficiency in preventing or smoothing over the negative effects of microgravity in the course and after long-term space flight. PMID:19238918

  14. SECURITY ISSUES AND COUNTERMEASURES FOR VOIP NETWORKS

    M.Rajeswari*,

    2015-01-01

    Full Text Available Voice over Internet Protocol (VoIP has been widely deployed since the integration of the voice and data networks reduces management effort and cost. Since VoIP share the same infrastructure with traditional data network, it inherits all security problems from data network. Furthermore, VoIP also has its own security problems coming from new protocols and network component. This paper focuses on these VoIP specific security threats and the countermeasures to mitigate the problem. At first, this paper gives a brief introduction of VoIP techniques: the network structure, network components, protocols and standards, data handling procedures, quality of service requirements. Secondly, the paper discusses the VoIP specific security threats using the principle of CIA (Confidentiality, Integrity and Availability. The countermeasure to mitigate these threats is also discussed. At last, the paper proposes the practice to secure VoIP networks.

  15. Zika Virus: Medical Countermeasure Development Challenges.

    Malone, Robert W.; Jane Homan; Michael V Callahan; Jill Glasspool-Malone; Lambodhar Damodaran; Adriano de Bernardi Schneider; Rebecca Zimler; James Talton; Cobb, Ronald R; Ivan Ruzic; Julie Smith-Gagen; Daniel Janies; James Wilson

    2016-01-01

    Reports of high rates of primary microcephaly and Guillain-Barré syndrome associated with Zika virus infection in French Polynesia and Brazil have raised concerns that the virus circulating in these regions is a rapidly developing neuropathic, teratogenic, emerging infectious public health threat. There are no licensed medical countermeasures (vaccines, therapies or preventive drugs) available for Zika virus infection and disease. The Pan American Health Organization (PAHO) predicts that Zika...

  16. Zika Virus: Medical Countermeasure Development Challenges

    Malone, Robert W.; Jane Homan; Michael V. Callahan; Jill Glasspool-Malone; Lambodhar Damodaran; Adriano de Bernardi Schneider; Rebecca Zimler; James Talton; Cobb, Ronald R; Ivan Ruzic; Julie Smith-Gagen; Daniel Janies; James Wilson

    2016-01-01

    Introduction: Reports of high rates of primary microcephaly and Guillain–Barré syndrome associated with Zika virus infection in French Polynesia and Brazil have raised concerns that the virus circulating in these regions is a rapidly developing neuropathic, teratogenic, emerging infectious public health threat. There are no licensed medical countermeasures (vaccines, therapies or preventive drugs) available for Zika virus infection and disease. The Pan American Health Organization (PAHO) pred...

  17. Countermeasures against railway ground and track vibrations

    Hildebrand, Robert

    2001-01-01

    Railway track and ground vibrations are considered, with anemphasis on methods of mitigation ("countermeasures"), forapplication to wayside disturbance problems. Original field measurements from two sites in Sweden, aswell as borrowed measurements from Norway, provide vibrationresults at many points on the track, on and underneath theground surface, for a variety of trains, both with and withoutcountermeasures in-place. Infinite periodic system theory is the basis of track-onlyand track-groun...

  18. Acoustic source for generating an acoustic beam

    Vu, Cung Khac; Sinha, Dipen N.; Pantea, Cristian

    2016-05-31

    An acoustic source for generating an acoustic beam includes a housing; a plurality of spaced apart piezo-electric layers disposed within the housing; and a non-linear medium filling between the plurality of layers. Each of the plurality of piezoelectric layers is configured to generate an acoustic wave. The non-linear medium and the plurality of piezo-electric material layers have a matching impedance so as to enhance a transmission of the acoustic wave generated by each of plurality of layers through the remaining plurality of layers.

  19. Zika Virus: Medical Countermeasure Development Challenges

    Malone, Robert W.; Homan, Jane; Callahan, Michael V.; Glasspool-Malone, Jill; Damodaran, Lambodhar; Schneider, Adriano De Bernardi; Zimler, Rebecca; Talton, James; Cobb, Ronald R.; Ruzic, Ivan; Smith-Gagen, Julie; Janies, Daniel; Wilson, James

    2016-01-01

    Introduction Reports of high rates of primary microcephaly and Guillain–Barré syndrome associated with Zika virus infection in French Polynesia and Brazil have raised concerns that the virus circulating in these regions is a rapidly developing neuropathic, teratogenic, emerging infectious public health threat. There are no licensed medical countermeasures (vaccines, therapies or preventive drugs) available for Zika virus infection and disease. The Pan American Health Organization (PAHO) predicts that Zika virus will continue to spread and eventually reach all countries and territories in the Americas with endemic Aedes mosquitoes. This paper reviews the status of the Zika virus outbreak, including medical countermeasure options, with a focus on how the epidemiology, insect vectors, neuropathology, virology and immunology inform options and strategies available for medical countermeasure development and deployment. Methods Multiple information sources were employed to support the review. These included publically available literature, patents, official communications, English and Lusophone lay press. Online surveys were distributed to physicians in the US, Mexico and Argentina and responses analyzed. Computational epitope analysis as well as infectious disease outbreak modeling and forecasting were implemented. Field observations in Brazil were compiled and interviews conducted with public health officials. PMID:26934531

  20. Zika Virus: Medical Countermeasure Development Challenges.

    Robert W Malone

    2016-03-01

    Full Text Available Reports of high rates of primary microcephaly and Guillain-Barré syndrome associated with Zika virus infection in French Polynesia and Brazil have raised concerns that the virus circulating in these regions is a rapidly developing neuropathic, teratogenic, emerging infectious public health threat. There are no licensed medical countermeasures (vaccines, therapies or preventive drugs available for Zika virus infection and disease. The Pan American Health Organization (PAHO predicts that Zika virus will continue to spread and eventually reach all countries and territories in the Americas with endemic Aedes mosquitoes. This paper reviews the status of the Zika virus outbreak, including medical countermeasure options, with a focus on how the epidemiology, insect vectors, neuropathology, virology and immunology inform options and strategies available for medical countermeasure development and deployment.Multiple information sources were employed to support the review. These included publically available literature, patents, official communications, English and Lusophone lay press. Online surveys were distributed to physicians in the US, Mexico and Argentina and responses analyzed. Computational epitope analysis as well as infectious disease outbreak modeling and forecasting were implemented. Field observations in Brazil were compiled and interviews conducted with public health officials.

  1. Acoustic Neuroma Educational Video

    Full Text Available ... Options Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask ... Options Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask ...

  2. Acoustic Neuroma Educational Video

    Full Text Available ... ANA Staff Medical Advisory Board News ANA Annual Reports Acoustic Neuroma Legacy Society Programs & Services Join/Renew ... ANA Staff Medical Advisory Board News ANA Annual Reports Acoustic Neuroma Legacy Society Programs & Services Search ANAUSA. ...

  3. Acoustic Neuroma Educational Video

    Full Text Available ... ANA Annual Reports Acoustic Neuroma Legacy Society Programs & Services Join/Renew Ways to Give ANA Discussion Forum ... ANA Annual Reports Acoustic Neuroma Legacy Society Programs & Services Search ANAUSA.org Connect with us! Educational Video ...

  4. Cystic acoustic neuromas

    Chitkara, Naveen; Chanda, Rakesh; Yadav, S. P. S.; N.K. Sharma

    2002-01-01

    Predominantly cystic acoustic neuromas are rare and they usually present with clinical and radiological features different from their more common solid counterparts. Two cases of cystic acoustic neuromas are reported here.

  5. Atlantic Herring Acoustic Surveys

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Advanced Sampling Technologies Research Group conducts annual fisheries acoustic surveys using state-of-the-art acoustic, midwater trawling, and...

  6. Acoustic Neuroma Educational Video

    Full Text Available ... Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself ... Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself ...

  7. Acoustic Neuroma Educational Video

    Full Text Available ... is ANA? Mission Statement Board of Directors ANA Staff Medical Advisory Board News ANA Annual Reports Acoustic ... is ANA? Mission Statement Board of Directors ANA Staff Medical Advisory Board News ANA Annual Reports Acoustic ...

  8. Acoustic Neuroma Educational Video

    Full Text Available ... Resources Patient Surveys Related Links Clinical Trials.gov Health Care Insurance Toolkit Additional Resources ANA Public Webinars © 2016 Acoustic Neuroma Association Acoustic Neuroma Association ® • ...

  9. 77 FR 15398 - Attentive Driving: Countermeasures for Distraction Forum

    2012-03-15

    ... SAFETY BOARD Attentive Driving: Countermeasures for Distraction Forum The National Transportation Safety Board (NTSB) will convene a forum, Attentive Driving: Countermeasures for Distraction, which will begin... the forum, and all five NTSB Board Members will serve as members of the Board of Inquiry. The forum...

  10. Human Adaptation to Space: Space Physiology and Countermeasures

    Fogarty, Jennifer

    2009-01-01

    This viewgraph presentation reviews human physiological responses to spaceflight, and the countermeasures taken to prevent adverse effects of manned space flight. The topics include: 1) Human Spaceflight Experience; 2) Human Response to Spaceflight; 3) ISS Expeditions 1-16; 4) Countermeasure; and 5) Biomedical Data;

  11. Countering countermeasures: detecting identity lies by detecting conscious breakthrough.

    Howard Bowman

    Full Text Available One major drawback of deception detection is its vulnerability to countermeasures, whereby participants wilfully modulate their physiological or neurophysiological response to critical guilt-determining stimuli. One reason for this vulnerability is that stimuli are usually presented slowly. This allows enough time to consciously apply countermeasures, once the role of stimuli is determined. However, by increasing presentation speed, stimuli can be placed on the fringe of awareness, rendering it hard to perceive those that have not been previously identified, hindering the possibility to employ countermeasures. We tested an identity deception detector by presenting first names in Rapid Serial Visual Presentation and instructing participants to lie about their own identity. We also instructed participants to apply a series of countermeasures. The method proved resilient, remaining effective at detecting deception under all countermeasures.

  12. Agricultural countermeasures in the Nordic countries after a nuclear accident

    This report by the NKSBOK-1.4 project group describes agricultural countermeasures after a nuclear accident, aiming at the reduction of radiation doses to man from the ingestion of foodstuffs. The intention has been to collect information based on common understanding that can be used as a Nordic handbook and in further developments of the national preparedness systems. The report covers two areas: the gathering and dissemination of information before and during a nuclear emergency, and the development of a countermeasures strategy. A number of factors are discussed, which will affect the choice of countermeasure(s), and as a case study, a technical cost-benefit assessment of a specific countermeasure is described. (au)

  13. Agricultural countermeasures in the Nordic countries after a nuclear accident

    Brink, M. [Danish Plant Directorate (Denmark); Lauritzen, B. [Risoe National Lab. (Denmark)] (eds.)

    2001-12-01

    This report by the NKSBOK-1.4 project group describes agricultural countermeasures after a nuclear accident, aiming at the reduction of radiation doses to man from the ingestion of foodstuffs. The intention has been to collect information based on common understanding that can be used as a Nordic handbook and in further developments of the national preparedness systems. The report covers two areas: the gathering and dissemination of information before and during a nuclear emergency, and the development of a countermeasures strategy. A number of factors are discussed, which will affect the choice of countermeasure(s), and as a case study, a technical cost-benefit assessment of a specific countermeasure is described. (au)

  14. Modeling ground vehicle acoustic signatures for analysis and synthesis

    Security and weapon systems use acoustic sensor signals to classify and identify moving ground vehicles. Developing robust signal processing algorithms for this is expensive, particularly in presence of acoustic clutter or countermeasures. This paper proposes a parametric ground vehicle acoustic signature model to aid the system designer in understanding which signature features are important, developing corresponding feature extraction algorithms and generating low-cost, high-fidelity synthetic signatures for testing. The authors have proposed computer-generated acoustic signatures of armored, tracked ground vehicles to deceive acoustic-sensored smart munitions. They have developed quantitative measures of how accurately a synthetic acoustic signature matches those produced by actual vehicles. This paper describes parameters of the model used to generate these synthetic signatures and suggests methods for extracting these parameters from signatures of valid vehicle encounters. The model incorporates wide-bandwidth and narrow- bandwidth components that are modulated in a pseudo-random fashion to mimic the time dynamics of valid vehicle signatures. Narrow- bandwidth feature extraction techniques estimate frequency, amplitude and phase information contained in a single set of narrow frequency- band harmonics. Wide-bandwidth feature extraction techniques estimate parameters of a correlated-noise-floor model. Finally, the authors propose a method of modeling the time dynamics of the harmonic amplitudes as a means adding necessary time-varying features to the narrow-bandwidth signal components. The authors present results of applying this modeling technique to acoustic signatures recorded during encounters with one armored, tracked vehicle. Similar modeling techniques can be applied to security systems

  15. ACOUSTICAL STANDARDS NEWS.

    Blaeser, Susan B; Struck, Christopher J

    2016-03-01

    American National Standards (ANSI Standards) developed by Accredited Standards Committees S1, S2, S3, S3/SC 1, and S12 in the areas of acoustics, mechanical vibration and shock, bioacoustics, animal bioacoustics, and noise, respectively, are published by the Acoustical Society of America (ASA). In addition to these standards, ASA publishes a catalog of Acoustical American National Standards. To receive a copy of the latest Standards catalog, please contact Susan B. Blaeser.Comments are welcomed on all material in Acoustical Standards News.This Acoustical Standards News section in JASA, as well as the National Catalog of Acoustical Standards and other information on the Standards Program of the Acoustical Society of America, are available via the ASA home page: http://acousticalsociety.org. PMID:27036268

  16. SECURITY ISSUES IN CLOUD COMPUTING AND COUNTERMEASURES

    DANISH JAMIL,

    2011-04-01

    Full Text Available Cloud computing technology is a new concept of providing dramatically scalable and virtualised resources, bandwidth, software and hardware on demand to consumers. Consumers can typically requests cloud services via a web browser or web service. Using cloud computing, consumers can safe cost of hardware deployment, software licenses and system maintenance. On the other hand, it also has a few security issues. This paper introduces four cloud security problems, which are XML Signature Element Wrapping, Browser Security, Cloud Malware Injection Attack and Flooding Attacks, and also gives the possible countermeasures.

  17. AST Launch Vehicle Acoustics

    Houston, Janice; Counter, D.; Giacomoni, D.

    2015-01-01

    The liftoff phase induces acoustic loading over a broad frequency range for a launch vehicle. These external acoustic environments are then used in the prediction of internal vibration responses of the vehicle and components which result in the qualification levels. Thus, predicting these liftoff acoustic (LOA) environments is critical to the design requirements of any launch vehicle. If there is a significant amount of uncertainty in the predictions or if acoustic mitigation options must be implemented, a subscale acoustic test is a feasible pre-launch test option to verify the LOA environments. The NASA Space Launch System (SLS) program initiated the Scale Model Acoustic Test (SMAT) to verify the predicted SLS LOA environments and to determine the acoustic reduction with an above deck water sound suppression system. The SMAT was conducted at Marshall Space Flight Center and the test article included a 5% scale SLS vehicle model, tower and Mobile Launcher. Acoustic and pressure data were measured by approximately 250 instruments. The SMAT liftoff acoustic results are presented, findings are discussed and a comparison is shown to the Ares I Scale Model Acoustic Test (ASMAT) results.

  18. Countermeasure for Radiation Protection and Repair

    2008-01-01

    Exposure to ionizing radiation during long-duration space missions is expected to cause short-term illness and increase long-term risk of cancer for astronauts. Radiation-induced free radicals overload the antioxidant defense mechanisms and lead to cellular damage at the membrane, enzyme, and chromosome levels. A large number of radioprotective agents were screened, but most had significant side effects. But there is increasing evidence that significant radioprotective benefit is achieved by increasing the dietary intake of foods with high antioxidant potential. Early plant-growing systems for space missions will be limited in both size and volume to minimize power and mass requirements. These systems will be well suited to producing plants containing high concentrations of bioprotective antioxidants. This project explored whether the production of bioprotective compounds could be increased by altering the lighting system, without increasing the space or power requirements for production, and evaluated the effects of environmental conditions (light quantity, light quality, and carbon dioxide [CO2] concentration) on the production of bioprotective compounds in lettuce, which provide a biological countermeasure for radiation exposure. The specific deliverables were to develop a database of bioprotectant compounds in plants that are suitable for use on longduration space missions, develop protocols for maintaining and increasing bioprotectant production under light emitting diodes (LEDs), recommend lighting requirements to produce dietary countermeasures of radiation, and publish results in the Journal of the American Society for Horticultural Science.

  19. Priority of areas for agricultural countermeasure assessment

    Within the overall preparedness related to nuclear and/or radiological accidents that lead to the release of radionuclides to the environment with the consequent contamination of agricultural areas, the priority of research for agricultural areas should then focus on the surrounding areas of nuclear power plants that have higher probability of public exposure through the ingestion pathway. The objective of this work was to create a rank order of priority of agricultural products to be considered in assessing the effects of countermeasures, based on both economic value and doses to the public. Additionally, the study describes relevant needs of radioecological studies to improve short and long-terms dose assessments. . Sixteen municipalities surrounding the Brazilian Nuclear Power Central were analyzed for a contamination with 137Cs, considering seasonal aspects related to agricultural practices in the Southeastern Brazil. Rank order provided by considering economical aspects shows that there is a need for radioecological research for some high value products, such as palmetto and sugar cane, and the need to include in the current model more detailed description for some food items, such as eggs. Combined rank criteria shows that main product within the considered area is milk. As so, the study of countermeasures for the ingestion of milk should be prioritized. (authors)

  20. Physiological strain and countermeasures with firefighting.

    Cheung, S S; Petersen, S R; McLellan, T M

    2010-10-01

    Protective clothing is integral to the task of firefighting, but at the same time can increase physiological strain and impair work capacity. Encapsulation of the head and the high thermal resistance and/or low water vapor permeability of the clothing ensemble impede evaporative heat dissipation, thus elevating the rate of heat storage and creating a state of uncompensable heat stress (UHS). In addition, the additional weight from carrying a supplemental air supply and the greater respiratory work of breathing through a regulator can create a negative spiral of thermal hyperpnea from greater respiratory demands and metabolic heat production. The elevated respiratory demands also increase cardiac strain and potentially the risk for myocardial events. Tolerance time during UHS is determined by three factors: the core temperature at the beginning of the heat stress exposure, the core temperature that can be tolerated before exhaustion or collapse ensues, and the rate of increase in core temperature from the beginning to end of the heat stress exposure. Protective clothing is often employed in highly dynamic environments, making portability, longevity and integration with the task requirements and clothing critical design characteristics for countermeasures. To date, most countermeasures have been relatively indirect in nature, primarily with alterations in work scheduling along with physiological manipulations such as cooling manipulations during recovery periods. Advances are required in materials science to develop lighter and less restrictive protective equipment, concurrent with cooling strategies that target specific regions or which can be effectively implemented during exercise. PMID:21029197

  1. Improved self-protection using dynamically optimized expendable countermeasures

    Hovland, Harald

    2007-04-01

    The use of expendable countermeasures is still found to be a viable choice for self protection against Man Portable Air Defense Systems (MANPADS) due to their simplicity, low cost, flexibility, recent improvements in decoy technology, the ability to handle multiple threats simultaneously and the off-board nature of these countermeasures. In civil aviation, the risk of general hazards linked to the use of pyrotechnics is the main argument against expendable countermeasures, whereas for military platforms, the limitation in capacity due to a limited number of rounds is often used as an argument to replace expendable countermeasures by laser-based countermeasures. This latter argument is in general not substantiated by modelling or figures of merit, although it is often argued that a laser based system allows for more false alarms, hence enabling a more sensitive missile approach warning system. The author has developed a model that accounts for the statistical effects of running out of expendable countermeasures during a mission, in terms of the overall mission survival probability. The model includes key parameters of the missile approach warning system (MAWS), and can handle multiple missile types and missile attack configurations, as well as various statistical models of missile attacks. The model enables quantitative comparison between laser based and expendable countermeasures, but also a dynamic optimization of the countermeasures in terms of whether to use small or large countermeasure programs, as well as the dynamic tuning of MAWS key parameters to optimize the overall performance. The model is also well suited for determination of the contributions of the different components of the system in the overall survival probability.

  2. Vibro-acoustics

    Nilsson, Anders

    2015-01-01

    This three-volume book gives a thorough and comprehensive presentation of vibration and acoustic theories. Different from traditional textbooks which typically deal with some aspects of either acoustic or vibration problems, it is unique of this book to combine those two correlated subjects together. Moreover, it provides fundamental analysis and mathematical descriptions for several crucial phenomena of Vibro-Acoustics which are quite useful in noise reduction, including how structures are excited, energy flows from an excitation point to a sound radiating surface, and finally how a structure radiates noise to a surrounding fluid. Many measurement results included in the text make the reading interesting and informative. Problems/questions are listed at the end of each chapter and the solutions are provided. This will help the readers to understand the topics of Vibro-Acoustics more deeply. The book should be of interest to anyone interested in sound and vibration, vehicle acoustics, ship acoustics and inter...

  3. Springer handbook of acoustics

    2014-01-01

    Acoustics, the science of sound, has developed into a broad interdisciplinary field encompassing the academic disciplines of physics, engineering, psychology, speech, audiology, music, architecture, physiology, neuroscience, and electronics. The Springer Handbook of Acoustics is also in his 2nd edition an unparalleled modern handbook reflecting this richly interdisciplinary nature edited by one of the acknowledged masters in the field, Thomas Rossing. Researchers and students benefit from the comprehensive contents. This new edition of the Handbook features over 11 revised and expanded chapters, new illustrations, and 2 new chapters covering microphone arrays  and acoustic emission.  Updated chapters contain the latest research and applications in, e.g. sound propagation in the atmosphere, nonlinear acoustics in fluids, building and concert hall acoustics, signal processing, psychoacoustics, computer music, animal bioacousics, sound intensity, modal acoustics as well as new chapters on microphone arrays an...

  4. Acoustic streaming in microchannels

    Tribler, Peter Muller

    , and experimental results for the streaming-induced drag force dominated motion of particles suspended in a water-filled microchannel supporting a transverse half-wavelength resonance. The experimental and theoretical results agree within a mean relative dierence of approximately 20%, a low deviation given state......This thesis presents studies of boundary-driven acoustic streaming in microfluidic channels, which is a steady flow of the fluid initiated by the interactions of an oscillating acoustic standing wave and the rigid walls of the microchannel. The studies present analysis of the acoustic resonance......, the acoustic streaming flow, and the forces on suspended microparticles. The work is motivated by the application of particle focusing by acoustic radiation forces in medical, environmental and food sciences. Here acoustic streaming is most often unwanted, because it limits the focusability of particles...

  5. Shallow Water Acoustic Laboratory

    Federal Laboratory Consortium — FUNCTION: Supports experimental research where high-frequency acoustic scattering and surface vibration measurements of fluid-loaded and non-fluid-loaded structures...

  6. Handbook of Engineering Acoustics

    Möser, Michael

    2013-01-01

    This book examines the physical background of engineering acoustics, focusing on empirically obtained engineering experience as well as on measurement techniques and engineering methods for prognostics. Its goal is not only to describe the state of art of engineering acoustics but also to give practical help to engineers in order to solve acoustic problems. It deals with the origin, the transmission and the methods of the abating different kinds of air-borne and structure-borne sounds caused by various mechanisms – from traffic to machinery and flow-induced sound. In addition the modern aspects of room and building acoustics, as well as psychoacoustics and active noise control, are covered.

  7. Acoustic dispersive prism

    Esfahlani, Hussein; Karkar, Sami; Lissek, Herve; Mosig, Juan R.

    2016-01-01

    The optical dispersive prism is a well-studied element, which allows separating white light into its constituent spectral colors, and stands in nature as water droplets. In analogy to this definition, the acoustic dispersive prism should be an acoustic device with capability of splitting a broadband acoustic wave into its constituent Fourier components. However, due to the acoustical nature of materials as well as the design and fabrication difficulties, there is neither any natural acoustic counterpart of the optical prism, nor any artificial design reported so far exhibiting an equivalent acoustic behaviour. Here, based on exotic properties of the acoustic transmission-line metamaterials and exploiting unique physical behaviour of acoustic leaky-wave radiation, we report the first acoustic dispersive prism, effective within the audible frequency range 800 Hz-1300 Hz. The dispersive nature, and consequently the frequency-dependent refractive index of the metamaterial are exploited to split the sound waves towards different and frequency-dependent directions. Meanwhile, the leaky-wave nature of the structure facilitates the sound wave radiation into the ambient medium.

  8. Localized Acoustic Surface Modes

    Farhat, Mohamed

    2015-08-04

    We introduce the concept of localized acoustic surface modes (ASMs). We demonstrate that they are induced on a two-dimensional cylindrical rigid surface with subwavelength corrugations under excitation by an incident acoustic plane wave. Our results show that the corrugated rigid surface is acoustically equivalent to a cylindrical scatterer with uniform mass density that can be represented using a Drude-like model. This, indeed, suggests that plasmonic-like acoustic materials can be engineered with potential applications in various areas including sensing, imaging, and cloaking.

  9. What Is an Acoustic Neuroma

    ... org Connect with us! What is an Acoustic Neuroma? Each heading slides to reveal information. Important Points ... Neuroma Important Points To Know About an Acoustic Neuroma An acoustic neuroma, also called a vestibular schwannoma, ...

  10. Development of Medical Countermeasures to Middle East Respiratory Syndrome Coronavirus.

    Uyeki, Timothy M; Erlandson, Karl J; Korch, George; O'Hara, Michael; Wathen, Michael; Hu-Primmer, Jean; Hojvat, Sally; Stemmy, Erik J; Donabedian, Armen

    2016-07-01

    Preclinical development of and research on potential Middle East respiratory syndrome coronavirus (MERS-CoV) medical countermeasures remain preliminary; advancements are needed before most countermeasures are ready to be tested in human clinical trials. Research priorities include standardization of animal models and virus stocks for studying disease pathogenesis and efficacy of medical countermeasures; development of MERS-CoV diagnostics; improved access to nonhuman primates to support preclinical research; studies to better understand and control MERS-CoV disease, including vaccination studies in camels; and development of a standardized clinical trial protocol. Partnering with clinical trial networks in affected countries to evaluate safety and efficacy of investigational therapeutics will strengthen efforts to identify successful medical countermeasures. PMID:27191188

  11. Development of Medical Countermeasures to Middle East Respiratory Syndrome Coronavirus

    Erlandson, Karl J.; Korch, George; O’Hara, Michael; Wathen, Michael; Hu-Primmer, Jean; Hojvat, Sally; Stemmy, Erik J.; Donabedian, Armen

    2016-01-01

    Preclinical development of and research on potential Middle East respiratory syndrome coronavirus (MERS-CoV) medical countermeasures remain preliminary; advancements are needed before most countermeasures are ready to be tested in human clinical trials. Research priorities include standardization of animal models and virus stocks for studying disease pathogenesis and efficacy of medical countermeasures; development of MERS-CoV diagnostics; improved access to nonhuman primates to support preclinical research; studies to better understand and control MERS-CoV disease, including vaccination studies in camels; and development of a standardized clinical trial protocol. Partnering with clinical trial networks in affected countries to evaluate safety and efficacy of investigational therapeutics will strengthen efforts to identify successful medical countermeasures. PMID:27191188

  12. Problems in Employment Trend of Higher Vocational Graduates and Countermeasures

    Tan, Jianhua; Sheng, Zhichong

    2011-01-01

    Based on analyzing the regional character of higher vocational graduates employment, this paper analyzes the reasons for this employment trend, advances relevant countermeasures for employment of higher vocational graduates, and explores the direction for higher vocational graduates employment.

  13. Bluetooth security attacks comparative analysis, attacks, and countermeasures

    Haataja, Keijo; Pasanen, Sanna; Toivanen, Pekka

    2013-01-01

    This overview of Bluetooth security examines network vulnerabilities and offers a comparative analysis of recent security attacks. It also examines related countermeasures and proposes a novel attack that works against all existing Bluetooth versions.

  14. Methodological approaches to analysis of agricultural countermeasures on radioactive contaminated areas: Estimation of effectiveness and comparison of different alternatives

    Yatsalo, B.I.; Hedemann Jensen, P.; Alexakhin, R.M.

    Methodological aspects of countermeasure analysis in the long-term period after a nuclear accident are discussed for agriculture countermeasures for illustrative purposes. The estimates of effectiveness fbr specific countermeasures as well as methods of justified action levels assessments and...

  15. Countermeasures of radioactive substances in food

    It consists of four chapters such as contamination in food, reference value of food, people's feeling, and roles of scientist. On contamination in food, many countermeasures are described, for example, establishment of the provisional regulation values of radioactive nuclides in food, shipment restriction of some kinds of vegetables, milk, tea, beef, and fish. The interim measures of protection for radioactive nuclides in food are stated in detail. New standard was established in April, 2012. Background of Japanese feeling on radiation and soil contamination from atomic bombs in 1945 to 2013 is explained. There is a need for establishment of risk management project and regulatory science by all scientists, for example, natural science, social science, and humanities. (S.Y.)

  16. GNSS-based positioning: Attacks and Countermeasures

    Papadimitratos, P

    2010-01-01

    Increasing numbers of mobile computing devices, user-portable, or embedded in vehicles, cargo containers, or the physical space, need to be aware of their location in order to provide a wide range of commercial services. Most often, mobile devices obtain their own location with the help of Global Navigation Satellite Systems (GNSS), integrating, for example, a Global Positioning System (GPS) receiver. Nonetheless, an adversary can compromise location-aware applications by attacking the GNSS-based positioning: It can forge navigation messages and mislead the receiver into calculating a fake location. In this paper, we analyze this vulnerability and propose and evaluate the effectiveness of countermeasures. First, we consider replay attacks, which can be effective even in the presence of future cryptographic GNSS protection mechanisms. Then, we propose and analyze methods that allow GNSS receivers to detect the reception of signals generated by an adversary, and then reject fake locations calculated because of ...

  17. Nuclear industry project audit and countermeasures

    With China's increasing use of nuclear energy, nuclear power related construction projects related to the deepening of the audit, some of the nuclear industry in construction field of the dominant issues have been more effective containment, such as inflated workload, high-set fixed standards, to improve billing unit price, which overestimate the risk calculation tools and behavior completed audit of the accounts have been able to escape his stuff. However, some nuclear industry construction field with a hidden problem because of its hidden nature, not easily found, and some even have intensified the trend. Construction funds to the country such problems caused by the loss of waste is enormous, to the breeding of corruption provided the soil is fertile, if not promptly and effectively to stop the breeding will spread. This paper on the current construction of the nuclear industry in several major areas of the hidden problems are discussed, and the angle from the audit of appropriate countermeasures. (authors)

  18. WIRELESS NETWORKS: DEVELOPMENTS, THREATS AND COUNTERMEASURES

    Mardiana Mohamad Noor

    2013-01-01

    Full Text Available This paper discusses current threats in wireless networks and some academia research reviews regarding the matters. Significant and persistent threats discussed are sniffing, Man In the Middle Attack (MITM, Rogue Access Points (RAP, Denial Of Services (DoS and social engineering attacks. Some current developments of wireless communication technology such as short range communication, cloud computing, bring your own device policy (BYOD, devices tethering and convergences of WiFi and cellular network technology are also presented. Some practical suggestion and advanced countermeasures are also reviewed in this paper. The findings from reviewing these research papers proved that the complexity of the attacks had increased by time and the attacks in WiFi network are passive and more dangerous to the end users.

  19. Factors influencing choice of countermeasure strategy

    There are number of countermeasures that can be used, singly and in combination, to reduce doses in the short-term following a nuclear accident. Which strategy is adopted will depend on local factors, such as the type of accident, local geography and demography, and the resources available, and on the form of national and international guidance is to facilitate a consistent level of response to accidents, wherever they occur, whilst at the same time providing for flexibility of response to suit local circumstances. This paper discusses the influence of all these factors on the choice of protective strategy. The goal of any off-site emergency response strategy should be the protection of the public, not just against radiation, but in the sense of providing overall benefit. To achieve this goal, differing local and national constraint mean that the precise strategy adopted may vary from site to site. (Authors). 22 refs., 1 fig., 2 tabs

  20. Countermeasure of thyratron related troubles at SACLA

    In the XFEL facility SACLA, more than 70 thyratrons are used as a high voltage switch device for an oil-filled line-type modulator. Since the thyratron is a deuterium-filled electron tube, which conducts several kA pulse through a plasma between narrow high voltage gaps, it sometimes makes abnormal pre-fires during the charging cycle, or fluctuation of the conduction loss which leads the fluctuation of the RF output from the klystron. Moreover, high surge voltage due to the connection in the plasma causes a damage on the TVS diode. We have investigated these troubles and applied several countermeasures for these problems. In order to check the performance of the thyratron, we performed 24-hours pre-install test in the test stand. (author)

  1. Acoustic emission source modeling

    Hora, Petr; Červená, Olga

    2010-01-01

    Roč. 4, č. 1 (2010), s. 25-36. ISSN 1802-680X R&D Projects: GA ČR GA101/09/1630 Institutional research plan: CEZ:AV0Z20760514 Keywords : acoustic emission source * wave propagation * FEM Subject RIV: BI - Acoustics

  2. Acoustic Neuroma Educational Video

    Full Text Available ... Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself Post-treatment Post-treatment ... Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself Post-treatment Post-treatment ...

  3. Acoustic Signals and Systems

    The Handbook of Signal Processing in Acoustics will compile the techniques and applications of signal processing as they are used in the many varied areas of Acoustics. The Handbook will emphasize the interdisciplinary nature of signal processing in acoustics. Each Section of the Handbook will...... present topics on signal processing which are important in a specific area of acoustics. These will be of interest to specialists in these areas because they will be presented from their technical perspective, rather than a generic engineering approach to signal processing. Non-specialists, or specialists...... from different areas, will find the self-contained chapters accessible and will be interested in the similarities and differences between the approaches and techniques used in different areas of acoustics....

  4. Ocean acoustic hurricane classification.

    Wilson, Joshua D; Makris, Nicholas C

    2006-01-01

    Theoretical and empirical evidence are combined to show that underwater acoustic sensing techniques may be valuable for measuring the wind speed and determining the destructive power of a hurricane. This is done by first developing a model for the acoustic intensity and mutual intensity in an ocean waveguide due to a hurricane and then determining the relationship between local wind speed and underwater acoustic intensity. From this it is shown that it should be feasible to accurately measure the local wind speed and classify the destructive power of a hurricane if its eye wall passes directly over a single underwater acoustic sensor. The potential advantages and disadvantages of the proposed acoustic method are weighed against those of currently employed techniques. PMID:16454274

  5. Cochlear bionic acoustic metamaterials

    Ma, Fuyin; Wu, Jiu Hui; Huang, Meng; Fu, Gang; Bai, Changan

    2014-11-01

    A design of bionic acoustic metamaterial and acoustic functional devices was proposed by employing the mammalian cochlear as a prototype. First, combined with the experimental data in previous literatures, it is pointed out that the cochlear hair cells and stereocilia cluster are a kind of natural biological acoustic metamaterials with the negative stiffness characteristics. Then, to design the acoustic functional devices conveniently in engineering application, a simplified parametric helical structure was proposed to replace actual irregular cochlea for bionic design, and based on the computational results of such a bionic parametric helical structure, it is suggested that the overall cochlear is a local resonant system with the negative dynamic effective mass characteristics. There are many potential applications in the bandboard energy recovery device, cochlear implant, and acoustic black hole.

  6. Computational Ocean Acoustics

    Jensen, Finn B; Porter, Michael B; Schmidt, Henrik

    2011-01-01

    Since the mid-1970s, the computer has played an increasingly pivotal role in the field of ocean acoustics. Faster and less expensive than actual ocean experiments, and capable of accommodating the full complexity of the acoustic problem, numerical models are now standard research tools in ocean laboratories. The progress made in computational ocean acoustics over the last thirty years is summed up in this authoritative and innovatively illustrated new text. Written by some of the field's pioneers, all Fellows of the Acoustical Society of America, Computational Ocean Acoustics presents the latest numerical techniques for solving the wave equation in heterogeneous fluid–solid media. The authors discuss various computational schemes in detail, emphasizing the importance of theoretical foundations that lead directly to numerical implementations for real ocean environments. To further clarify the presentation, the fundamental propagation features of the techniques are illustrated in color. Computational Ocean A...

  7. Validation of a Cephalad Fluid Shift Countermeasure

    Macias, B.; Cole, C.; Kesari, S.; Hargens, A.; Stenger, M.; Ebert, D.; Lee, S. M. C.; Sargsyan, A.; Liu, J.

    2016-01-01

    INTRODUCTION: This project will provide critical data required to objectively determine how an optimized thigh cuff could be incorporated into the NASA integrated physiological countermeasure suite. This project will determine if thigh cuffs used during simulated spaceflight impact intracranial pressure (ICP), ocular structure and function, and intraocular pressure (IOP) using state of-the-art techniques. Additionally, some of the same methods, hardware, and protocols will be employed in the present investigation to enable direct comparisons to the International Space Station (ISS) "Fluid Shifts" experiment with Chibis-Lower Body Negative Pressure (LBNP). This study will determine the temporal physiological responses of thigh cuff application and removal on ocular and cerebral variables (including invasive ICP) in a microgravity analog. Furthermore, this proposed study will determine tissue pressure distribution applied by thigh cuffs in order to improve comfort, mobility, and efficacy of the countermeasure. Our specific aim is to determine the efficacy of a novel thigh cuff device to mitigate cephalad fluid shifts. We hypothesize that a thigh cuff countermeasure employed in a microgravity analog will temporarily reverse or attenuate ocular and cerebral-volume-pressure variables, approaching normal Earth-based seated posture, the most frequent posture assumed in daily life. In addition, we hypothesize that the magnitude of fluid and pressure redistribution using a thigh cuff countermeasure may require a longer exposure time than that of Chibis-LBNP (using ground-based data from our "Fluid Shifts" project). This project directly addresses Critical Path Roadmap Risks and Questions regarding "Risk of Spaceflight-Induced Intracranial Hypertension/Vision Alterations," and IRP Gap VIIP13: We need to identify preventative and treatment countermeasures to mitigate changes in ocular structure and function and intracranial pressure during spaceflight. METHODS: Noninvasive

  8. Flat acoustic lens by acoustic grating with curled slits

    We design a flat sub-wavelength lens that can focus acoustic wave. We analytically study the transmission through an acoustic grating with curled slits, which can serve as a material with tunable impedance and refractive index for acoustic waves. The effective parameters rely on the geometry of the slits and are independent of frequency. A flat acoustic focusing lens by such acoustic grating with gradient effective refractive index is designed. The focusing effect is clearly observed in simulations and well predicted by the theory. We demonstrate that despite the large impedance mismatch between the acoustic lens and the matrix, the intensity at the focal point is still high due to Fabry–Perot resonance. - Highlights: • Expression of transmission coefficient of an acoustic grating with curled slits. • Non-dispersive and tunable effective medium parameters for the acoustic grating. • A flat acoustic focusing lens with gradient index by using the acoustic grating

  9. From Architectural Acoustics to Acoustical Architecture Using Computer Simulation

    Schmidt, Anne Marie Due; KIRKEGAARD, Poul Henning

    2005-01-01

    Architectural acoustics design has in the past been based on simple design rules. However, with a growing complexity in architectural acoustics and the emergence of room acoustic simulation programmes with considerable potential, it is now possible to subjectively analyse and evaluate acoustic properties prior to the actual construction of a building. With the right tools applied, acoustic design can become an integral part of the architectural design process. The aim of this paper is to inve...

  10. Processing of foodstuffs as countermeasures following a nuclear accident

    The processing of foodstuffs is one of the countermeasures which may be taken following a nuclear accident in order to reduce the contamination of the foodstuffs concerned. A consideration of the transfer of radioactivity during the processing or the preparation of food makes it possible to estimate the effectiveness of the countermeasure concerned, which is one essential criterion for its selection; the other is the cost of its application. In short, consideration must be given at the same time to both of these factors if a rational choice is to be made between the various potential options on an industrial scale. In addition to the countermeasures involving processing or culinary preparation of the foodstuffs concerned, they may also be destroyed, stored, used as feedingstuffs or decontaminated, and the crops may be buried, the feedingstuffs of animals changed, farmland frozen, etc. An expert system using the GOLDWORKS software should help to select the most appropriate countermeasure on the basis of its cost and effectiveness. Such a system would evaluate: - the effectiveness of each of the countermeasures likely to be selected (to be expressed in terms of dose); - the social cost of the dose avoided by their application; - the cost of the countermeasure itself. The last is estimated as thoroughly as possible by taking into account, inter alia, food processing, compensation to the producers, the costs of transport and storage or of destruction. This is followed by a proposed classification of the countermeasures according to their cost effectiveness. 17 radionuclides and 4 foodstuffs (milk, meat, green vegetables and cereals) are considered. Depending on the date of the accident concerned, the input data for themodel are produced from the concentrations measured in the foodstuffs or in the soil. In the latter case, dynamic transfer coefficients make it possible to evaluate the contamination of future harvests

  11. Evaluation of the effectiveness of countermeasures in contaminated forests

    In many regions subjected to the contamination forest products play an important role in radiation impact on the population. The contribution of mushrooms and berries to the internal doses varies depending on the time after the accident up to 40-45%. To protect people against additional exposure associated with forest contamination an appropriate system of countermeasures should be applied. The decision making framework to optimise implementation of forest countermeasures in the long term after the ChNPP accident is described. The approach is based on the analysis of the main exposure pathways related to contaminated forest and application of different criteria (reduction of individual dose to population and members of critical groups, cost for countermeasures implementation; cost of averted dose of 1 man-Sv; secondary ecological effect and psycho-social impact) for the selection of optimal countermeasures strategies. Because of diversity of these criteria for selection of optimal countermeasures a decision support technology based on a multi-attributive analysis is applied. Results of the application of the approach proposed for the study area (Novozybkov district, Bryansk region, Russian Federation) are presented. Applicability of twelve forest countermeasure options is evaluated and their effectiveness in terms of cost and dose reduction is estimated for the current period. It has been found that limitation on mushrooms or berries collections to the species with low accumulation of radionuclides and mushrooms processing before consumption (for the population) and combined application of Prussian Blue with limitation of tree harvesting to the area with low doses to decrease exposure of the critical groups members are most justified for the long term after the accident in the most contaminated regions of Russia. The results emphasize the effectiveness of the application of a flexible technique to provide the optimization of forest countermeasures taking into

  12. Predicting Acoustics in Class Rooms

    Christensen, Claus Lynge; Rindel, Jens Holger

    2005-01-01

    Typical class rooms have fairly simple geometries, even so room acoustics in this type of room is difficult to predict using today's room acoustic computer modeling software. The reasons why acoustics of class rooms are harder to predict than acoustics of complicated concert halls might be...

  13. Underwater Applications of Acoustical Holography

    P. C. Mehta

    1984-01-01

    Full Text Available The paper describes the basic technique of acoustical holography. Requirements for recording the acoustical hologram are discussed with its ability for underwater imaging in view. Some practical systems for short-range and medium-range imaging are described. The advantages of acoustical holography over optical imaging, acoustical imaging and sonars are outlined.

  14. Countermeasures for dairy products in nuclear emergencies

    This work was performed in order to plan countermeasures that, after an accidental release of radioactivity, could reduce the dose to the public due to the consumption of contaminated milk and milk products. The attention was focused on whether there are justified and optimised actions below the international recommended concentration levels in foodstuffs. The analysis was conducted as a case study, i.e., it was assumed that a hypothetical accident had happened in a nuclear power plant leading to a release of radionuclides which severely contaminated a wide area of Ostrobothnia, one of Finland's most important milk production areas. The dose averted by actions, the' monetary costs and the feasibility of actions were assessed. It was also studied what information is needed by decision-makers and in which form this information should be presented. Finally, it was examined how planning of countermeasures could be enhanced by applying decision analysis in establishing actions strategies and valuing attributes considered in decision making. Preparative meetings and a concluding workshop was arranged and all authorities involved in food-related emergency management were invited to jointly analyse different options. According to the query made the participants considered the decision workshop and decision analysis very practicable in exercises. The exercise as a whole was also evaluated useful or very useful. The presented techniques in a real situation were considered applicable but not as useful as in exercises. Thus it can be deduced that the concluding workshop and decision analysis interviews augment well conventional emergency exercises. Realistic dose assessments proved out to be very difficult. The software used was able to calculate the maximum radionuclide concentrations in foodstuffs processed from local raw materials. Radionuclide concentration in food or feedstuffs may, however, change quickly. Also, the production and processing of foodstuffs is a complex

  15. 76 FR 48169 - Advancing Regulatory Science for Highly Multiplexed Microbiology/Medical Countermeasure Devices...

    2011-08-08

    ... Microbiology/ Medical Countermeasure Devices; Public Meeting AGENCY: Food and Drug Administration, HHS. ACTION... following public meeting: ``Advancing Regulatory Science for Highly Multiplexed Microbiology/Medical... multiplexed microbiology/medical countermeasure (MCM) devices, their clinical application and public...

  16. Tunable acoustic metamaterials

    Babaee, Sahab; Viard, Nicolas; Fang, Nicholas; Bertoldi, Katia

    2015-03-01

    We report a new class of active and switchable acoustic metamaterials composed of three-dimensional stretchable chiral helices arranged on a two-dimensional square lattice. We investigate the propagation of sounds through the proposed structure both numerically and experimentally and find that the deformation of the helices can be exploited as a novel and effective approach to control the propagation of acoustic waves. The proposed concept expands the ability of existing acoustic metamaterials since we demonstrate that the deformation can be exploited to turn on or off the band gap, opening avenues for the design of adaptive noise-cancelling devices.

  17. Acoustic module of the Acquabona (Italy debris flow monitoring system

    A. Galgaro

    2005-01-01

    Full Text Available Monitoring of debris flows aimed to the assessment of their physical parameters is very important both for theoretical and practical purposes. Peak discharge and total volume of debris flows are crucial for designing effective countermeasures in many populated mountain areas where losses of lives and property damage could be avoided. This study quantifies the relationship between flow depth, acoustic amplitude of debris flow induced ground vibrations and front velocity in the experimental catchment of Acquabona, Eastern Dolomites, Italy. The analysis of data brought about the results described in the following. Debris flow depth and amplitude of the flow-induced ground vibrations show a good positive correlation. Estimation of both mean front velocity and peak discharge can be simply obtained monitoring the ground vibrations, through geophones installed close to the flow channel; the total volume of debris flow can be so directly estimated from the integral of the ground vibrations using a regression line. The application of acoustic technique to debris flow monitoring seems to be of the outmost relevance in risk reduction policies and in the correct management of the territory. Moreover this estimation is possible in other catchments producing debris flows of similar characteristics by means of their acoustic characterisation through quick and simple field tests (Standard Penetration Tests and seismic refraction surveys.

  18. Acoustic module of the Acquabona (Italy) debris flow monitoring system

    Galgaro, A.; Tecca, P. R.; Genevois, R.; Deganutti, A. M.

    2005-02-01

    Monitoring of debris flows aimed to the assessment of their physical parameters is very important both for theoretical and practical purposes. Peak discharge and total volume of debris flows are crucial for designing effective countermeasures in many populated mountain areas where losses of lives and property damage could be avoided. This study quantifies the relationship between flow depth, acoustic amplitude of debris flow induced ground vibrations and front velocity in the experimental catchment of Acquabona, Eastern Dolomites, Italy. The analysis of data brought about the results described in the following. Debris flow depth and amplitude of the flow-induced ground vibrations show a good positive correlation. Estimation of both mean front velocity and peak discharge can be simply obtained monitoring the ground vibrations, through geophones installed close to the flow channel; the total volume of debris flow can be so directly estimated from the integral of the ground vibrations using a regression line. The application of acoustic technique to debris flow monitoring seems to be of the outmost relevance in risk reduction policies and in the correct management of the territory. Moreover this estimation is possible in other catchments producing debris flows of similar characteristics by means of their acoustic characterisation through quick and simple field tests (Standard Penetration Tests and seismic refraction surveys).

  19. Phononic crystals and acoustic metamaterials

    Ming-Hui Lu; Liang Feng; Yan-Feng Chen

    2009-01-01

    Phononic crystals have been proposed about two decades ago and some important characteristics such as acoustic band structure and negative refraction have stimulated fundamental and practical studies in acoustic materials and devices since then. To carefully engineer a phononic crystal in an acoustic “atom” scale, acoustic metamaterials with their inherent deep subwavelength nature have triggered more exciting investigations on negative bulk modulus and/or negative mass density. Acoustic surf...

  20. Thermal Acoustic Fatigue Apparatus

    Federal Laboratory Consortium — The Thermal Acoustic Fatigue Apparatus (TAFA) is a progressive wave tube test facility that is used to test structures for dynamic response and sonic fatigue due to...

  1. Acoustic integrated extinction

    Norris, Andrew N

    2015-01-01

    The integrated extinction (IE) is defined as the integral of the scattering cross-section as a function of wavelength. Sohl et al. [1] derived an IE expression for acoustic scattering that is causal, i.e. the scattered wavefront in the forward direction arrives later than the incident plane wave in the background medium. The IE formula was based on electromagnetic results, for which scattering is causal by default. Here we derive a formula for the acoustic IE that is valid for causal and non-causal scattering. The general result is expressed as an integral of the time dependent forward scattering function. The IE reduces to a finite integral for scatterers with zero long-wavelength monopole and dipole amplitudes. Implications for acoustic cloaking are discussed and a new metric is proposed for broadband acoustic transparency.

  2. Acoustics Noise Test Cell

    Federal Laboratory Consortium — The Acoustic Noise Test Cell at the NASA/Caltech Jet Propulsion Laboratory (JPL) is located adjacent to the large vibration system; both are located in a class 10K...

  3. Principles of musical acoustics

    Hartmann, William M

    2013-01-01

    Principles of Musical Acoustics focuses on the basic principles in the science and technology of music. Musical examples and specific musical instruments demonstrate the principles. The book begins with a study of vibrations and waves, in that order. These topics constitute the basic physical properties of sound, one of two pillars supporting the science of musical acoustics. The second pillar is the human element, the physiological and psychological aspects of acoustical science. The perceptual topics include loudness, pitch, tone color, and localization of sound. With these two pillars in place, it is possible to go in a variety of directions. The book treats in turn, the topics of room acoustics, audio both analog and digital, broadcasting, and speech. It ends with chapters on the traditional musical instruments, organized by family. The mathematical level of this book assumes that the reader is familiar with elementary algebra. Trigonometric functions, logarithms and powers also appear in the book, but co...

  4. Compact acoustic refrigerator

    Bennett, Gloria A.

    1992-01-01

    A compact acoustic refrigeration system actively cools components, e.g., electrical circuits (22), in a borehole environment. An acoustic engine (12, 14) includes first thermodynamic elements (12) for generating a standing acoustic wave in a selected medium. An acoustic refrigerator (16, 26, 28) includes second thermodynamic elements (16) located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements (16) and a relatively hot temperature at a second end of the second thermodynamic elements (16). A resonator volume (18) cooperates with the first and second thermodynamic elements (12, 16) to support the standing wave. To accommodate the high heat fluxes required for heat transfer to/from the first and second thermodynamic elements (12, 16), first heat pipes (24, 26) transfer heat from the heat load (22) to the second thermodynamic elements (16) and second heat pipes (28, 32) transfer heat from first and second thermodynamic elements (12, 16) to the borehole environment.

  5. Acoustics lecturing in Mexico

    Beristain, Sergio

    2002-11-01

    Some thirty years ago acoustics lecturing started in Mexico at the National Polytechnic Institute in Mexico City, as part of the Bachelor of Science degree in Communications and Electronics Engineering curricula, including the widest program on this field in the whole country. This program has been producing acoustics specialists ever since. Nowadays many universities and superior education institutions around the country are teaching students at the B.Sc. level and postgraduate level many topics related to acoustics, such as Architectural Acoustics, Seismology, Mechanical Vibrations, Noise Control, Audio, Audiology, Music, etc. Also many institutions have started research programs in related fields, with participation of medical doctors, psychologists, musicians, engineers, etc. Details will be given on particular topics and development.

  6. Acoustic Igniter Project

    National Aeronautics and Space Administration — An acoustic igniter eliminates the need to use electrical energy to drive spark systems to initiate combustion in liquid-propellant rockets. It does not involve the...

  7. Acoustic Neuroma Educational Video

    Full Text Available ... treatment Summary Types Of Post-treatment Issues Resources Medical Resources Considerations When Selecting a Healthcare Professional Healthcare ... ANA? Mission Statement Board of Directors ANA Staff Medical Advisory Board News ANA Annual Reports Acoustic Neuroma ...

  8. Acoustic coherent perfect absorbers

    In this paper, we explore the possibility of achieving acoustic coherent perfect absorbers. Through numerical simulations in two dimensions, we demonstrate that the energy of coherent acoustic waves can be totally absorbed by a fluid absorber with specific complex mass density or bulk modulus. The robustness of such absorbing systems is investigated under small perturbations of the absorber parameters. We find that when the resonance order is the lowest and the size of the absorber is comparable to the wavelength in the background, the phenomenon of perfect absorption is most stable. When the wavelength inside both the background and the absorber is much larger than the size of the absorber, perfect absorption is possible when the mass density of the absorber approaches the negative value of the background mass density. Finally, we show that by using suitable dispersive acoustic metamaterials, broadband acoustic perfect absorption may be achieved. (papers)

  9. Ocean acoustic reverberation tomography.

    Dunn, Robert A

    2015-12-01

    Seismic wide-angle imaging using ship-towed acoustic sources and networks of ocean bottom seismographs is a common technique for exploring earth structure beneath the oceans. In these studies, the recorded data are dominated by acoustic waves propagating as reverberations in the water column. For surveys with a small receiver spacing (e.g., tomography, is developed that uses the travel times of direct and reflected waves to image ocean acoustic structure. Reverberation tomography offers an alternative approach for determining the structure of the oceans and advancing the understanding of ocean heat content and mixing processes. The technique has the potential for revealing small-scale ocean thermal structure over the entire vertical height of the water column and along long survey profiles or across three-dimensional volumes of the ocean. For realistic experimental geometries and data noise levels, the method can produce images of ocean sound speed on a smaller scale than traditional acoustic tomography. PMID:26723303

  10. Autonomous Acoustic Receiver System

    Federal Laboratory Consortium — FUNCTION: Collects underwater acoustic data and oceanographic data. Data are recorded onboard an ocean buoy and can be telemetered to a remote ship or shore station...

  11. Initial Basis for Agronomic Countermeasure Selection Following a Nuclear Accident

    During the recovery stage, following a nuclear accident, application of agricultural countermeasures will be relevant to the minimization of the radiation induced detriment due to ingestion of locally produced contaminated foodstuff, as long as the magnitude of the averted dose is sufficient to justify their implementation. Nuclear emergency planning in Argentina currently holds food ban as the accepted countermeasure, at least until other measures are taken. Though it may ensure no residual collective dose, food ban may also imply very high costs, compared to other alternatives, specially due to the need of disposing off perishable food such as milk. Therefore, an exhaustive evaluation of all the alternatives, considering both quantitative and qualitative factors is still needed to identify optimal countermeasure strategies, bearing in mind also that decisions made during the early phase of an emergency will affect the fate of the measures to be taken later. As a first step in this direction, a basic quantitative decis sion-aiding technique, the cost-benefit analysis, is carried out for comparison of countermeasures related to Cesium contaminated cow-milk which are considered feasible for implementation in Argentina. Countermeasures total costs are estimated from various local sources, while their effectiveness are adopted from international bibliography. At this stage, a simple theoretical example considering milk contamination in the surroundings of the Embalse Nuclear Power Plant is used for a generic analysis, since actual collective doses and costs can only be calculated for a specific modelled scenario. (authors)

  12. Smart Grid Integrity Attacks: Characterizations and Countermeasures

    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.

  13. Radiation. Basics, influences, contamination situation, and countermeasures

    Fukushima Daiichi Nuclear Accident resulted in the contamination of a large area, and by now the situation of contamination and exposure has gradually clarified, and a lot of information has been being accumulated. Toward reconstruction of Fukushima prefecture from the current circumstance that the residents still live under continuing fear, this article discusses how to clarify the current situation and deal with the contamination, which the residents are concerned about. First, radiation, basic properties of radiation, and so on are introduced. Regarding the influence on human bodies, the mechanism and the degree of influence by radiation, especially on children, women, and pregnant women are explained. Next, regarding the measurements of radiation and radioactivity, the properties of measurement methods and the detectors are explained. Regarding the current situation of contamination and exposure, mainly addressing the area around Koriyama city, various topics are covered including: (1) situation of contamination and radiation monitoring, (2) countermeasures for radioactivity contamination, (3) internal exposure dose, (4) exposed dose from water and food, as well as (5) safety standards. (S.K.)

  14. Anal acoustic reflectometry

    Mitchell, Peter J; Klarskov, Niels; Telford, Karen J; Hosker, Gordon L; Lose, Gunnar; Kiff, Edward S

    2011-01-01

    Anal acoustic reflectometry is a new technique of assessing anal sphincter function. Five new variables reflecting anal canal function are measured: the opening and closing pressure, the opening and closing elastance, and hysteresis.......Anal acoustic reflectometry is a new technique of assessing anal sphincter function. Five new variables reflecting anal canal function are measured: the opening and closing pressure, the opening and closing elastance, and hysteresis....

  15. The autonomous acoustic buoy

    Pellicer, Francisco; Reitsma, Robert; Agüera, Joaquín; Marinas, Alexandra

    2013-01-01

    The Acoustic Buoy is a project between the Laboratory of Applied Bioacoustics (LAB) and the Universitat Politècnica de Catalunya (UPC). In areas that the human activities produce high noise levels, such as oil exploration or construction, there is a need to monitor the environment for the presence of cetaceans. Another need is for fishing, to prevent endangered species from being killed. This can be done with an Autonomous Acoustic Buoy (AAB). Mooring or anchoring at to the seaflo...

  16. Acoustic emission source modeling

    Hora, Petr; Červená, Olga

    Plzeň : University of West Bohemia, 2009 - (Adámek, V.; Zajíček, M.). s. 1-2 ISBN 978-80-7043-824-4. [Výpočtová mechanika 2009. 09.11.2009-11.11.2009, Nečtiny] R&D Projects: GA ČR GA101/09/1630 Institutional research plan: CEZ:AV0Z20760514 Keywords : acoustic emission source * wave propagation * FEM Subject RIV: BI - Acoustics

  17. Wavefront modulation and subwavelength diffractive acoustics with an acoustic metasurface.

    Xie, Yangbo; Wang, Wenqi; Chen, Huanyang; Konneker, Adam; Popa, Bogdan-Ioan; Cummer, Steven A

    2014-01-01

    Metasurfaces are a family of novel wavefront-shaping devices with planar profile and subwavelength thickness. Acoustic metasurfaces with ultralow profile yet extraordinary wave manipulating properties would be highly desirable for improving the performance of many acoustic wave-based applications. However, designing acoustic metasurfaces with similar functionality to their electromagnetic counterparts remains challenging with traditional metamaterial design approaches. Here we present a design and realization of an acoustic metasurface based on tapered labyrinthine metamaterials. The demonstrated metasurface can not only steer an acoustic beam as expected from the generalized Snell's law, but also exhibits various unique properties such as conversion from propagating wave to surface mode, extraordinary beam-steering and apparent negative refraction through higher-order diffraction. Such designer acoustic metasurfaces provide a new design methodology for acoustic signal modulation devices and may be useful for applications such as acoustic imaging, beam steering, ultrasound lens design and acoustic surface wave-based applications. PMID:25418084

  18. Stakeholder involvement for countermeasures in the food chain

    In the aftermath of a large scale radioactive contamination, the authorities will have to decide on protective measures for reducing the contamination of the food chain. The overall aim is to reduce the dose of the population to an acceptable level while still guaranteeing sufficient foodstuffs and feeding stuffs on the market and also to limit the social, environmental and economic impact of the countermeasures implemented. Many countermeasures have been developed over the years, but their large scale feasibility and especially their acceptability have hardly been studied. Within the context of a European research project called Farming (2000-2004). SCK-CEN has organised stakeholder meetings, leading to guidance to the authorities for improvements in the emergency organisation. To improve emergency countermeasure decisions related to the food chain, especially as regards feasibility and acceptability, taking into account stakeholder opinions. The stakeholders include scientists and representatives from both governmental and non-governmental organisations

  19. Disaster countermeasures around nuclear facilities in self-governing bodies

    In Tokai Village, Ibaraki Prefecture, a nuclear disaster countermeasure training practice was carried out on November 5, 1981, assuming the occurrence of an abnormal state in Tokai No. 2 Nuclear Power Station of JAPC. In the morning, the prefectural and village disaster countermeasure headquarters were set up, and first environmental monitoring was conducted, and various countermeasures were determined. In the afternoon, second environmental monitoring with newly movilized personnel and instruments, and also traffic control and the evacuation of people were carried out. Sixty-eight organizations, 1530 persons, two helicopters, one patrol boat, 153 vehicles, etc. participated in the training practice. The following matters are described: purpose, scenario, the items of practice, results, future problems. (Mori, K.)

  20. Acoustic vector sensor signal processing

    SUN Guiqing; LI Qihu; ZHANG Bin

    2006-01-01

    Acoustic vector sensor simultaneously, colocately and directly measures orthogonal components of particle velocity as well as pressure at single point in acoustic field so that is possible to improve performance of traditional underwater acoustic measurement devices or detection systems and extends new ideas for solving practical underwater acoustic engineering problems. Although acoustic vector sensor history of appearing in underwater acoustic area is no long, but with huge and potential military demands, acoustic vector sensor has strong development trend in last decade, it is evolving into a one of important underwater acoustic technology. Under this background, we try to review recent progress in study on acoustic vector sensor signal processing, such as signal detection, DOA estimation, beamforming, and so on.

  1. The Need for Continued Development of Ricin Countermeasures

    Ronald B. Reisler

    2012-01-01

    Full Text Available Ricin toxin, an extremely potent and heat-stable toxin produced from the bean of the ubiquitous Ricinus communis (castor bean plant, has been categorized by the US Centers for Disease Control and Prevention (CDC as a category B biothreat agent that is moderately easy to disseminate. Ricin has the potential to be used as an agent of biological warfare and bioterrorism. Therefore, there is a critical need for continued development of ricin countermeasures. A safe and effective prophylactic vaccine against ricin that was FDA approved for “at risk” individuals would be an important first step in assuring the availability of medical countermeasures against ricin.

  2. Safety Assessment and Countermeasures of Genetically Modified Food

    2013-05-01

    Full Text Available With the rapid development of science-biotechnology, the safety of genetically modified organisms has become some of the most controversial issues in our society. This study aims to review the safety assessment and countermeasures of Genetically Modified (GM foods. Firstly, the research status and the main contents of GM foods safety assessment are discussed. What’s more, the countermeasures of GM foods safety assessment are proposed. This study tries to summarize and discuss the safety assessment of GM foods.

  3. Acoustic comfort in eating establishments

    Svensson, David; Jeong, Cheol-Ho; Brunskog, Jonas

    2014-01-01

    The subjective concept of acoustic comfort in eating establishments has been investigated in this study. The goal was to develop a predictive model for the acoustic comfort, by means of simple objective parameters, while also examining which other subjective acoustic parameters could help explain...... the feeling of acoustic comfort. Through several layers of anal ysis, acoustic comfort was found to be rather complex, and could not be explained entirely by common subjective parameters such as annoyance, intelligibility or privacy. A predictive model for the mean acoustic comfort for an eating...

  4. Phononic crystals and acoustic metamaterials

    Ming-Hui Lu

    2009-12-01

    Full Text Available Phononic crystals have been proposed about two decades ago and some important characteristics such as acoustic band structure and negative refraction have stimulated fundamental and practical studies in acoustic materials and devices since then. To carefully engineer a phononic crystal in an acoustic “atom” scale, acoustic metamaterials with their inherent deep subwavelength nature have triggered more exciting investigations on negative bulk modulus and/or negative mass density. Acoustic surface evanescent waves have also been recognized to play key roles to reach acoustic subwavelength imaging and enhanced transmission.

  5. Fire protection countermeasures for containment ventilation systems

    The goal of this project is to find countermeasures to protect HEPA filters in exit ventilation ducts from the heat and smoke generated by fire. Several methods for partially mitigating the smoke exposure to the HEPA filters were identified through testing and analysis. These independently involve controlling the fuel, controlling the fire, and intercepting the smoke aerosol prior to its sorption on the HEPA filter. Exit duct treatment of aerosols is not unusual in industrial applications and involves the use of scrubbers, prefilters, and inertial impaction, depending on the size, distribution, and concentration of the subject aerosol. However, when these unmodified techniques were applied to smoke aerosols from fires on materials, common to experimental laboratories of LLNL, it was found they offered minimal protection to the HEPA filters. Ultimately, a continuous, movable, high-efficiency prefilter using modified commercial equipment was designed. This technique is capable of protecting HEPA filters over the total duration of the test fires. The reason for success involved the modificaton of the prefiltration media. Commercially available filter media has a particle sorption efficiency that is inversely proportional to media strength. To achieve properties of both efficiency and strength, we laminated rolling filter media with the desired properties. It is not true that the use of rolling prefilters solely to protect HEPA filters from fire-generated smoke aerosols is cost effective in every type of containment system, especially if standard fire-protection systems are available in the space. But in areas of high fire risk, where the potential fuel load is large and ignition sources are plentiful, the complication of a rolling prefilter in exit ventilation ducts to protect HEPA filters from smoke aerosols is definitely justified

  6. CAUSES AND COUNTERMEASURES FOR CHAOHU LAKESHORE COLLAPSE

    GAO Chao; WANG Xin-yuan; YANG Ze-dong; LU Ying-cheng; HE Hui

    2005-01-01

    By interpreting the remote sensing data of aerial photos and satellite images in different time, combining with field investigation, landform and water level observation, collecting data of weather, hydrology in Chaohu Lake, Anhui Province from 1957 to 2003, the reasons for collapse of Chaohu lakeshore were analyzed. The results are as follows: 1) The collapse of the Chaohu lakeshore is controlled macroscopically by two sets of north-east and the north-west faults, and the degree of collapse is determined microcosmically by lithology. 2) The constant change of water level, resulting from precipitation, wind speed and its direction, is one of the main reasons for intermittence collapse. 3) The soil and water loss or mud and sand filling up, resulting from artificial factors, such as inconsequence control of Chaohu sluice or irrational agricultural and industrial activities, etc., can uplift the lake's bed and drive water level up. The high water level also results in the collapse. Judging from the above mentioned reasons for the collapse, we have proposed some countermeasures: 1) Putting the lakeshore slope protection project such as stone and cement mortar into practice, and upstream slope should be 1:2.5 or 1:3, some parts of them should be 1:4, if they were not stable. The back slope, which is from Gui Mountain to Zhongmiao Temple, should be 1:1.5-1:3.2) Constructing a greenbelt for the lakeshore, planting some vegetation such as osier, bulrush and poplar, to resist waves between the high and the low water level. 3) Controlling Chaohu Lake water level scientifically. Corrosion of lakeshore that contains gravel clay and ferruginous-manganese concretionary structures, can decrease at low water level. 4) Renovating Chaohu Lake drainage area, strengthening the administration and supervision, breaking regionalism and establishing special administration organization.

  7. Fire protection countermeasures for containment ventilation systems

    The goal of this project is to find countermeasures to protect High Efficiency Particulate Air (HEPA) filters, in exit ventilation ducts, from the heat and smoke generated by fire. Initially, methods were developed to cool fire-heated air by fine water spray upstream of the filters. It was recognized that smoke aerosol exposure to HEPA filters could also cause disruption of the containment system. Through testing and analysis, several methods to partially mitigate the smoke exposure to the HEPA filters were identified. A continuous, movable, high-efficiency prefilter using modified commercial equipment was designed. The technique is capable of protecting HEPA filters over the total time duration of the test fires. The reason for success involved the modification of the prefiltration media. Commercially available filter media has particle sorption efficiency that is inversely proportional to media strength. To achieve properties of both efficiency and strength, rolling filter media were laminated with the desired properties. The approach was Edisonian, but truncation in short order to a combination of prefilters was effective. The application of this technique was qualified, since it is of use only to protect HEPA filters from fire-generated smoke aerosols. It is not believed that this technique is cost effective in the total spectrum of containment systems, especially if standard fire protection systems are available in the space. But in areas of high-fire risk, where the potential fuel load is large and ignition sources are plentiful, the complication of a rolling prefilter in exit ventilation ducts to protect HEPA filters from smoke aerosols is definitely justified

  8. Fire protection countermeasures for containment ventilation systems

    Alvares, N.; Beason, D.; Bergman, V.; Creighton, J.; Ford, H.; Lipska, A.

    1980-08-25

    The goal of this project is to find countermeasures to protect High Efficiency Particulate Air (HEPA) filters, in exit ventilation ducts, from the heat and smoke generated by fire. Initially, methods were developed to cool fire-heated air by fine water spray upstream of the filters. It was recognized that smoke aerosol exposure to HEPA filters could also cause disruption of the containment system. Through testing and analysis, several methods to partially mitigate the smoke exposure to the HEPA filters were identified. A continuous, movable, high-efficiency prefilter using modified commercial equipment was designed. The technique is capable of protecting HEPA filters over the total time duration of the test fires. The reason for success involved the modification of the prefiltration media. Commercially available filter media has particle sorption efficiency that is inversely proportional to media strength. To achieve properties of both efficiency and strength, rolling filter media were laminated with the desired properties. The approach was Edisonian, but truncation in short order to a combination of prefilters was effective. The application of this technique was qualified, since it is of use only to protect HEPA filters from fire-generated smoke aerosols. It is not believed that this technique is cost effective in the total spectrum of containment systems, especially if standard fire protection systems are available in the space. But in areas of high-fire risk, where the potential fuel load is large and ignition sources are plentiful, the complication of a rolling prefilter in exit ventilation ducts to protect HEPA filters from smoke aerosols is definitely justified.

  9. Fire protection countermeasures for containment ventilation systems

    Alvares, N.J.; Beason, D.G.; Bergman, W.; Ford, H.W.; Lipska, A.E.

    1980-01-01

    The goal of this project is to find countermeasures to protect HEPA filters in exit ventilation ducts from the heat and smoke generated by fire. Several methods for partially mitigating the smoke exposure to the HEPA filters were identified through testing and analysis. These independently involve controlling the fuel, controlling the fire, and intercepting the smoke aerosol prior to its sorption on the HEPA filter. Exit duct treatment of aerosols is not unusual in industrial applications and involves the use of scrubbers, prefilters, and inertial impaction, depending on the size, distribution, and concentration of the subject aerosol. However, when these unmodified techniques were applied to smoke aerosols from fires on materials, common to experimental laboratories of LLNL, it was found they offered minimal protection to the HEPA filters. Ultimately, a continuous, movable, high-efficiency prefilter using modified commercial equipment was designed. This technique is capable of protecting HEPA filters over the total duration of the test fires. The reason for success involved the modificaton of the prefiltration media. Commercially available filter media has a particle sorption efficiency that is inversely proportional to media strength. To achieve properties of both efficiency and strength, we laminated rolling filter media with the desired properties. It is not true that the use of rolling prefilters solely to protect HEPA filters from fire-generated smoke aerosols is cost effective in every type of containment system, especially if standard fire-protection systems are available in the space. But in areas of high fire risk, where the potential fuel load is large and ignition sources are plentiful, the complication of a rolling prefilter in exit ventilation ducts to protect HEPA filters from smoke aerosols is definitely justified.

  10. From Architectural Acoustics to Acoustical Architecture Using Computer Simulation

    Schmidt, Anne Marie Due; Kirkegaard, Poul Henning

    2005-01-01

    Architectural acoustics design has in the past been based on simple design rules. However, with a growing complexity in architectural acoustics and the emergence of room acoustic simulation programmes with considerable potential, it is now possible to subjectively analyse and evaluate acoustic...... properties prior to the actual construction of a building. With the right tools applied, acoustic design can become an integral part of the architectural design process. The aim of this paper is to investigate the field of application that an acoustic simulation programme can have during an architectural...... the first phases in the architectural process and set out a reverse strategy for simulation programmes to do so - from developing acoustics from given spaces to developing spaces from given acoustics...

  11. Wavefront Modulation and Subwavelength Diffractive Acoustics with an Acoustic Metasurface

    Xie, Yangbo; Wang, Wenqi; Chen, Huanyang; Konneker, Adam; Popa, Bogdan-Ioan; Cummer, Steven A.

    2014-01-01

    Metasurfaces are a family of novel wavefront shaping devices with planar profile and subwavelength thickness. Acoustic metasurfaces with ultralow profile yet extraordinary wave manipulating properties would be highly desirable for improving the performance of many acoustic wave-based applications. However, designing acoustic metasurfaces with similar functionality as their electromagnetic counterparts remains challenging with traditional metamaterial design approaches. Here we present a desig...

  12. ACOUSTICS IN ARCHITECTURAL DESIGN, AN ANNOTATED BIBLIOGRAPHY ON ARCHITECTURAL ACOUSTICS.

    DOELLE, LESLIE L.

    THE PURPOSE OF THIS ANNOTATED BIBLIOGRAPHY ON ARCHITECTURAL ACOUSTICS WAS--(1) TO COMPILE A CLASSIFIED BIBLIOGRAPHY, INCLUDING MOST OF THOSE PUBLICATIONS ON ARCHITECTURAL ACOUSTICS, PUBLISHED IN ENGLISH, FRENCH, AND GERMAN WHICH CAN SUPPLY A USEFUL AND UP-TO-DATE SOURCE OF INFORMATION FOR THOSE ENCOUNTERING ANY ARCHITECTURAL-ACOUSTIC DESIGN…

  13. Acoustic detection of pneumothorax

    Mansy, Hansen A.; Royston, Thomas J.; Balk, Robert A.; Sandler, Richard H.

    2003-04-01

    This study aims at investigating the feasibility of using low-frequency (pneumothorax detection were tested in dogs. In the first approach, broadband acoustic signals were introduced into the trachea during end-expiration and transmitted waves were measured at the chest surface. Pneumothorax was found to consistently decrease pulmonary acoustic transmission in the 200-1200-Hz frequency band, while less change was observed at lower frequencies (ppneumothorax states (pPneumothorax was found to be associated with a preferential reduction of sound amplitude in the 200- to 700-Hz range, and a decrease of sound amplitude variation (in the 300 to 600-Hz band) during the respiration cycle (pPneumothorax changed the frequency and decay rate of percussive sounds. These results imply that certain medical conditions may be reliably detected using appropriate acoustic measurements and analysis. [Work supported by NIH/NHLBI #R44HL61108.

  14. Seamount acoustic scattering

    Boehlert, George W.

    The cover of the March 1 issue of Eos showed a time series of acoustic scattering above Southeast Hancock Seamount (29°48‧N, 178°05‧E) on July 17-18, 1984. In a comment on that cover Martin Hovland (Eos, August 2, p. 760) argued that gas or “other far reaching causes” may be involved in the observed acoustic signals. He favors a hypothesis that acoustic scattering observed above a seeping pockmark in the North Sea is a combination of bubbles, stable microbubbles, and pelagic organisms and infers that this may be a more general phenomenon and indeed plays a role in the attraction of organisms to seamounts

  15. Acoustics waves and oscillations

    Sen, S.N.

    2013-01-01

    Parameters of acoustics presented in a logical and lucid style Physical principles discussed with mathematical formulations Importance of ultrasonic waves highlighted Dispersion of ultrasonic waves in viscous liquids explained This book presents the theory of waves and oscillations and various applications of acoustics in a logical and simple form. The physical principles have been explained with necessary mathematical formulation and supported by experimental layout wherever possible. Incorporating the classical view point all aspects of acoustic waves and oscillations have been discussed together with detailed elaboration of modern technological applications of sound. A separate chapter on ultrasonics emphasizes the importance of this branch of science in fundamental and applied research. In this edition a new chapter ''Hypersonic Velocity in Viscous Liquids as revealed from Brillouin Spectra'' has been added. The book is expected to present to its readers a comprehensive presentation of the subject matter...

  16. Practical acoustic emission testing

    2016-01-01

    This book is intended for non-destructive testing (NDT) technicians who want to learn practical acoustic emission testing based on level 1 of ISO 9712 (Non-destructive testing – Qualification and certification of personnel) criteria. The essential aspects of ISO/DIS 18436-6 (Condition monitoring and diagnostics of machines – Requirements for training and certification of personnel, Part 6: Acoustic Emission) are explained, and readers can deepen their understanding with the help of practice exercises. This work presents the guiding principles of acoustic emission measurement, signal processing, algorithms for source location, measurement devices, applicability of testing methods, and measurement cases to support not only researchers in this field but also and especially NDT technicians.

  17. A Century of Acoustic Metrology

    Rasmussen, Knud

    The development in acoustic measurement technique over the last century is reviewed with special emphasis on the metrological aspect.......The development in acoustic measurement technique over the last century is reviewed with special emphasis on the metrological aspect....

  18. A New Wave of Acoustics.

    Beyer, Robert

    1981-01-01

    Surveys 50 years of acoustical studies by discussing selected topics including the ear, nonlinear representations, underwater sound, acoustical diagnostics, absorption, electrolytes, phonons, magnetic interaction, and superfluidity and the five sounds. (JN)

  19. Advanced Active Acoustics Lab (AAAL)

    Federal Laboratory Consortium — The Advanced Active Acoustics Lab (AAAL) is a state-of-the-art Undersea Warfare (USW) acoustic data analysis facility capable of both active and passive underwater...

  20. Densitometry By Acoustic Levitation

    Trinh, Eugene H.

    1989-01-01

    "Static" and "dynamic" methods developed for measuring mass density of acoustically levitated solid particle or liquid drop. "Static" method, unknown density of sample found by comparison with another sample of known density. "Dynamic" method practiced with or without gravitational field. Advantages over conventional density-measuring techniques: sample does not have to make contact with container or other solid surface, size and shape of samples do not affect measurement significantly, sound field does not have to be know in detail, and sample can be smaller than microliter. Detailed knowledge of acoustic field not necessary.

  1. Acoustic black holes

    Visser, M

    1999-01-01

    Acoustic propagation in a moving fluid provides a conceptually clean and powerful analogy for understanding black hole physics. As a teaching tool, the analogy is useful for introducing students to both General Relativity and fluid mechanics. As a research tool, the analogy helps clarify what aspects of the physics are kinematics and what aspects are dynamics. In particular, Hawking radiation is a purely kinematical effect, whereas black hole entropy is intrinsically dynamical. Finally, I discuss the fact that with present technology acoustic Hawking radiation is almost experimentally testable.

  2. Strong acoustic wave action

    Gokhberg, M. B.

    1983-07-01

    Experiments devoted to acoustic action on the atmosphere-magnetosphere-ionosphere system using ground based strong explosions are reviewed. The propagation of acoustic waves was observed by ground observations over 2000 km in horizontal direction and to an altitude of 200 km. Magnetic variations up to 100 nT were detected by ARIEL-3 satellite near the epicenter of the explosion connected with the formation of strong field aligned currents in the magnetosphere. The enhancement of VLF emission at 800 km altitude is observed.

  3. Structural Acoustics and Vibrations

    Chaigne, Antoine

    This structural chapter is devoted to vibrations of structures and to their coupling with the acoustic field. Depending on the context, the radiated sound can be judged as desirable, as is mostly the case for musical instruments, or undesirable, like noise generated by machinery. In architectural acoustics, one main goal is to limit the transmission of sound through walls. In the automobile industry, the engineers have to control the noise generated inside and outside the passenger compartment. This can be achieved by means of passive or active damping. In general, there is a strong need for quieter products and better sound quality generated by the structures in our daily environment.

  4. The Main Problems and Countermeasures of English Classroom Talk

    Qian Bojie

    2015-01-01

    Full Text Available English classroom talk is one of the effective media for knowledge transfer in the English classroom, and how to use it effectively is a problem worth discussing. This article summarizes the main problems of English classroom talk through the analysis of its characteristics, and finally puts forward targeted counter-measures.

  5. Countermeasures of Implementing Sustainable Development Strategy in Shandong, China

    Cui Jianhai

    2004-01-01

    This paper set forth the goals of implementing sustainable development strategy in Shandong Province guided by the view of scientific development of being people oriented, comprehensive,coordinated and sustainable. Based on the target of sustainable development strategy in Shandong province this paper discusses the main tasks in the sustainable development strategy Countermeasures for sustainable development strategy in Shandong province are put forward.

  6. Analysis of the Reasons and Countermeasures for Academic Corruption

    Jin, Xia; Bin, Feng

    2007-01-01

    This paper presents a perspective of the various types of academic corruption that is currently running rife in society, a theoretical analysis of the roots of academic corruption, and proposals for a number for countermeasures to put a stop to academic corruption. (Contains 3 notes.) [This article was translated by Ted Wang.

  7. Pollution of Solid Waste to Agricultural Environment and Preventive Countermeasures

    Yan, Shi

    2014-01-01

    This paper elaborated the pollution and hazards caused by different kinds of agricultural solid wastes to the agro-ecological environment from the aspects of the types of solid wastes and the way they are produced. Besides, it came up with some countermeasures for preventing and controlling solid waste pollution and hazards.

  8. Behaviour of radionuclides in meadows including countermeasures application

    Main regularities of the behaviour of ChNPP release radionuclides in components of meadow ecosystems are considered. Developed mathematical model of radionuclide migration in components of meadow ecosystems is discussed. Radioecological classification of meadow ecosystems is proposed. Effectiveness of countermeasures application in meadow ecosystems is estimated

  9. Evaluation of countermeasures in agriculture and food processing

    Different countermeasures to decrease the contamination of plant and animal products after a nuclear accident are discussed. These countermeasures include the discarding and storing of contaminated goods as well as the use of additional agricultural techniques and industrial processing. Impending meat and milk contamination may be countered by feeding strontium and caesium sorbents such as calcium alginates, bentonite, and potassium hexacyanoferrates, thus inhibiting the strontium and caesium resorption in the gastrointestinal tract, or by distributing fodder with a higher contamination level to livestock used for breeding and not for meat and milk production. Techniques involving industrial decontamination include milk processing as well as alcohol and starch production. The removal or processing of highly contaminated by-products is given special attention. For all countermeasures the probable contamination reduction as well as the costs involved are stated. A method to optimize the selection of adequate countermeasures in a given situation is discussed. The different suggestions are designed to help political decision makers in the event of radioactive contamination. (author). 20 refs

  10. Causes for Ineffective College English Teaching and Relevant Countermeasures

    Li, Changyu; Li, Lijuan

    2009-01-01

    Through a questionnaire and a survey, the paper analyses the present College English teaching and the contributing factors for the ineffective College English teaching. Based on the analysis, the paper suggests four countermeasures to improve College English teaching quality. According to this paper, only when teachers and educational workers…

  11. The Situation and Countermeasures of Accounting Teaching in China

    Jinyu Yang

    2015-01-01

    The economic development proposes new issues for accounting teaching, which not only relies on educators¡¯ own perfection as well as the joint efforts of the accounting practitioners and social parties. The author briefly described the new circumstances the accounting education faces in recent years, summarized the characteristics of accounting teaching and proposed countermeasures to these accounting teaching issues.

  12. Effect of countermeasures on radionuclide uptake by green plants

    In the present paper results will be discussed in the field of countermeasures effectiveness on the radiocaesium and radiostrontium transfer to plants in relation to soil characteristics at the different sites investigated, as well as their influence on the crop yield. Refs. 4 (author)

  13. Pollution of Solid Waste to Agricultural Environment and Preventive Countermeasures

    Shi; YAN

    2014-01-01

    This paper elaborated the pollution and hazards caused by different kinds of agricultural solid wastes to the agro-ecological environment from the aspects of the types of solid wastes and the way they are produced. Besides,it came up with some countermeasures for preventing and controlling solid waste pollution and hazards.

  14. Radiation countermeasures from Himalayan herbs - an update

    A successful radioprotector is the one, which essentially renders protection from the multi-organ dis-function syndrome (MODS) caused by the total body exposure to ionizing radiation. Our rationale is that and instead of a single molecule, a group of molecules/compounds working synergistically can combat the MODS more effectively. Plant extracts offer natural combinations of a plethora of compounds, which act through different mechanisms and are, therefore, the ideal choice. Plants of Himalayan regions have survived under extreme climatic conditions through millions of years and are expected to harbor a battery of anti-stress adaptive molecules offering survival benefits. Our group is actively engaged in developing composite herbal radioprotective preparations from Himalayan Plants. This group is working to develop radiation countermeasures by tapping the essential complex phytochemicals from the plants inhabiting extreme climatic zones of Himalayas. In our laboratory, systematic studies were undertaken to investigate some of these plants located at high altitude regions of Himalayas viz. Hippophae rhamnoides, Rhodiola imbricata and Podophylium hexandruin. The most effective preparation from each of these plants individually, could provide more than 80% survival benefit to the irradiated (10 Gy) mice population against zero per cent survival in non-drug treated irradiated (10 Gy) mice population. It was observed that whole extracts of plant provided much better protection than the partial extracts/fractions. It was also observed that some of the partial extracts/fractions although, provided much higher survival benefits, yet were found to be unsuitable for drug development due to much higher mutagenic and/or recombinogenic effects in comparison to the whole extracts, One of the preparations from leaves of Hippophae rhamnoides (drug) showed more than 90% survival benefits in the irradiated mice population. Only one time intra-peritoneal administration of the drug

  15. Acoustic subwavelength imaging of subsurface objects with acoustic resonant metalens

    Cheng, Ying; Liu, XiaoJun, E-mail: liuxiaojun@nju.edu.cn [Key Laboratory of Modern Acoustics, Nanjing University, Nanjing 210093 (China); State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190 (China); Zhou, Chen; Wei, Qi; Wu, DaJian [Key Laboratory of Modern Acoustics, Nanjing University, Nanjing 210093 (China)

    2013-11-25

    Early research into acoustic metamaterials has shown the possibility of achieving subwavelength near-field acoustic imaging. However, a major restriction of acoustic metamaterials is that the imaging objects must be placed in close vicinity of the devices. Here, we present an approach for acoustic imaging of subsurface objects far below the diffraction limit. An acoustic metalens made of holey-structured metamaterials is used to magnify evanescent waves, which can rebuild an image at the central plane. Without changing the physical structure of the metalens, our proposed approach can image objects located at certain distances from the input surface, which provides subsurface signatures of the objects with subwavelength spatial resolution.

  16. Acoustic subwavelength imaging of subsurface objects with acoustic resonant metalens

    Early research into acoustic metamaterials has shown the possibility of achieving subwavelength near-field acoustic imaging. However, a major restriction of acoustic metamaterials is that the imaging objects must be placed in close vicinity of the devices. Here, we present an approach for acoustic imaging of subsurface objects far below the diffraction limit. An acoustic metalens made of holey-structured metamaterials is used to magnify evanescent waves, which can rebuild an image at the central plane. Without changing the physical structure of the metalens, our proposed approach can image objects located at certain distances from the input surface, which provides subsurface signatures of the objects with subwavelength spatial resolution

  17. COMBUSTION ACOUSTICS DIAGNOSTICS

    This is an Exploratory Research Project that was awarded by APPCD for research on developing an acoustic flame condition monitor. It will involve a bench scale experiment of 4-6 weeks duration to record adjacent audible energy of a Bunsen burner. The experiment will require a d...

  18. Acoustic Signals and Systems

    present topics on signal processing which are important in a specific area of acoustics. These will be of interest to specialists in these areas because they will be presented from their technical perspective, rather than a generic engineering approach to signal processing. Non-specialists, or specialists...

  19. Underwater Acoustic Networking Techniques

    Otnes, Roald; Casari, Paolo; Goetz, Michael; Husøy, Thor; Nissen, Ivor; Rimstad, Knut; van Walree, Paul; Zorzi, Michele

    2012-01-01

    This literature study presents an overview of underwater acoustic networking. It provides a background and describes the state of the art of all networking facets that are relevant for underwater applications. This report serves both as an introduction to the subject and as a summary of existing protocols, providing support and inspiration for the development of network architectures.

  20. Use of acoustic monitoring system for debris flow discharge evaluation

    Galgaro, A. G.; Tecca, P. R.; Genevois, R.; Deganutti, A. M.

    2003-04-01

    In 1997 an automated system for monitoring of debris flows has been installed in the Acquabona channel Dolomites, Italy. Induction geophones, with a specific frequency of 10 Hz, measure the amplitude of vertical ground vibrations generated by the passage of a flowing mass along the channel. Continuous acoustic logs and ultrasonic hydrograph recorded at the lower-channel measurement station for the debris flow of August 17, 1998, show a striking correspondence. This correspondence, already observed in different flow sites, is represented by the best fit between flow depth and flow sensor amplitude. Average front velocity for surges, calculated from the signal peak time shift and the distance between the sensors along the flow path, range between 2.00 and 7.7 m/s. As the ultrasonic sensor provides a way to measure the variation of the flow section area with the flow depth, the debris flow peak discharge may be estimated; obtained values of debris flow peak discharge range from 4 and 30 m3/s. Volumes were calculated by integrating instantaneous discharges through the hydrograph and by integrating the geophone log (acoustic flux). Volumes of 13700 m3 and 15500 m3 have been respectively obtained. The slight difference between the two values may result from the fact that acoustic records: i) are sensitive to the high frequencies, typical of the debris flow tails; ii) sum up the contributions sent by the whole flowing mass, while the ecometer detect the flow depth at every time at only one section. As a consequence the rising of the whole geophone log gives a higher value at the integration result. This only acoustic system can give a reasonably proxy for discharge and total volumes involved, which are among the most important parameters for debris flow hazard assessment and planning countermeasures. This methodology can be used in other debris flow sites if they are calibrated by the acoustic characterization of debris, obtained by both seismic surveys and SPT tests, and

  1. Flat acoustic lens by acoustic grating with curled slits

    Peng, Pai

    2014-10-01

    We design a flat sub-wavelength lens that can focus acoustic wave. We analytically study the transmission through an acoustic grating with curled slits, which can serve as a material with tunable impedance and refractive index for acoustic waves. The effective parameters rely on the geometry of the slits and are independent of frequency. A flat acoustic focusing lens by such acoustic grating with gradient effective refractive index is designed. The focusing effect is clearly observed in simulations and well predicted by the theory. We demonstrate that despite the large impedance mismatch between the acoustic lens and the matrix, the intensity at the focal point is still high due to Fabry-Perot resonance.

  2. Acoustic classification of dwellings

    Berardi, Umberto; Rasmussen, Birgit

    2014-01-01

    Schemes for the classification of dwellings according to different building performances have been proposed in the last years worldwide. The general idea behind these schemes relates to the positive impact a higher label, and thus a better performance, should have. In particular, focusing on sound...... insulation performance, national schemes for sound classification of dwellings have been developed in several European countries. These schemes define acoustic classes according to different levels of sound insulation. Due to the lack of coordination among countries, a significant diversity in terms of...... descriptors, number of classes, and class intervals occurred between national schemes. However, a proposal “acoustic classification scheme for dwellings” has been developed recently in the European COST Action TU0901 with 32 member countries. This proposal has been accepted as an ISO work item. This paper...

  3. Acoustic methodology review

    Schlegel, R. G.

    1982-01-01

    It is important for industry and NASA to assess the status of acoustic design technology for predicting and controlling helicopter external noise in order for a meaningful research program to be formulated which will address this problem. The prediction methodologies available to the designer and the acoustic engineer are three-fold. First is what has been described as a first principle analysis. This analysis approach attempts to remove any empiricism from the analysis process and deals with a theoretical mechanism approach to predicting the noise. The second approach attempts to combine first principle methodology (when available) with empirical data to formulate source predictors which can be combined to predict vehicle levels. The third is an empirical analysis, which attempts to generalize measured trends into a vehicle noise prediction method. This paper will briefly address each.

  4. Acoustic Tractor Beam

    Démoré, Christine E. M.; Dahl, Patrick M.; Yang, Zhengyi; Glynne-Jones, Peter; Melzer, Andreas; Cochran, Sandy; MacDonald, Michael P.; Spalding, Gabriel C.

    2014-05-01

    Negative radiation forces act opposite to the direction of propagation, or net momentum, of a beam but have previously been challenging to definitively demonstrate. We report an experimental acoustic tractor beam generated by an ultrasonic array operating on macroscopic targets (>1 cm) to demonstrate the negative radiation forces and to map out regimes over which they dominate, which we compare to simulations. The result and the geometrically simple configuration show that the effect is due to nonconservative forces, produced by redirection of a momentum flux from the angled sides of a target and not by conservative forces from a potential energy gradient. Use of a simple acoustic setup provides an easily understood illustration of the negative radiation pressure concept for tractor beams and demonstrates continuous attraction towards the source, against a net momentum flux in the system.

  5. Acoustics Discipline Overview

    Envia, Edmane; Thomas, Russell

    2007-01-01

    As part of the Fundamental Aeronautics Program Annual Review, a summary of the progress made in 2007 in acoustics research under the Subsonic Fixed Wing project is given. The presentation describes highlights from in-house and external activities including partnerships and NRA-funded research with industry and academia. Brief progress reports from all acoustics Phase 1 NRAs are also included as are outlines of the planned activities for 2008 and all Phase 2 NRAs. N+1 and N+2 technology paths outlined for Subsonic Fixed Wing noise targets. NRA Round 1 progressing with focus on prediction method advancement. NRA Round 2 initiating work focused on N+2 technology, prediction methods, and validation. Excellent partnerships in progress supporting N+1 technology targets and providing key data sets.

  6. The acoustics of snoring.

    Pevernagie, Dirk; Aarts, Ronald M; De Meyer, Micheline

    2010-04-01

    Snoring is a prevalent disorder affecting 20-40% of the general population. The mechanism of snoring is vibration of anatomical structures in the pharyngeal airway. Flutter of the soft palate accounts for the harsh aspect of the snoring sound. Natural or drug-induced sleep is required for its appearance. Snoring is subject to many influences such as body position, sleep stage, route of breathing and the presence or absence of sleep-disordered breathing. Its presentation may be variable within or between nights. While snoring is generally perceived as a social nuisance, rating of its noisiness is subjective and, therefore, inconsistent. Objective assessment of snoring is important to evaluate the effect of treatment interventions. Moreover, snoring carries information relating to the site and degree of obstruction of the upper airway. If evidence for monolevel snoring at the site of the soft palate is provided, the patient may benefit from palatal surgery. These considerations have inspired researchers to scrutinize the acoustic characteristics of snoring events. Similarly to speech, snoring is produced in the vocal tract. Because of this analogy, existing techniques for speech analysis have been applied to evaluate snoring sounds. It appears that the pitch of the snoring sound is in the low-frequency range (noise-like', and has scattered energy content in the higher spectral sub-bands (>500 Hz). To evaluate acoustic properties of snoring, sleep nasendoscopy is often performed. Recent evidence suggests that the acoustic quality of snoring is markedly different in drug-induced sleep as compared with natural sleep. Most often, palatal surgery alters sound characteristics of snoring, but is no cure for this disorder. It is uncertain whether the perceived improvement after palatal surgery, as judged by the bed partner, is due to an altered sound spectrum. Whether some acoustic aspects of snoring, such as changes in pitch, have predictive value for the presence of

  7. Acoustic emission source modeling

    Hora P.

    2010-07-01

    Full Text Available The paper deals with the acoustic emission (AE source modeling by means of FEM system COMSOL Multiphysics. The following types of sources are used: the spatially concentrated force and the double forces (dipole. The pulse excitation is studied in both cases. As a material is used steel. The computed displacements are compared with the exact analytical solution of point sources under consideration.

  8. 77 FR 52746 - Medical Countermeasures for a Burn Mass Casualty Incident

    2012-08-30

    ... pathways to facilitate medical countermeasures development and use; (3) develop logistics and operational... ] in disaster management (including medical utilization and response integration); FDA's role...

  9. Research on the Countermeasures against Electromagnetic Interface in Power Systems

    Lee, Won Bin; Kang, Young Suk; Choi, Hyo Yul; Cha, Ok Hyun [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Lee, Gi Chul; Le, Jae Bok; Ha, Tae Hyun; Kim, Suk Joo; Na, Dae Yul; Kim, Yong Ho; Jeong, Kyo Beom [Korea Electrotechnology Research Institute, Changwon (Korea, Republic of)

    1996-12-31

    As the results of widespread use of microelectronics in electric power system, electric environment of power operation facilities in substation has become more weak and severe for surge voltages. Electromagnetic coupled overvoltage caused by HV bus switching operating lead to the malfunction or destruction of low voltage control circuit which mostly used signal. To scope with this transients overvoltage, it is necessary to be investigated transient source and propagation path and analysed its effects to low voltage circuit such as relay. This study is to analysis source of conducted EMP(electromagnetic pulse) on the low voltage control circuit and to acquits transient voltage waveforms, and to provide countermeasures against transient voltage, and EMP filtering method according to each EMP each type. With this, gradual improvement of EMI countermeasure will be achieved. (author). 49 refs., figs.

  10. Psychosomatic problems and countermeasures in Japanese children and adolescents

    Tanaka Hidetaka

    2012-03-01

    Full Text Available Abstract In Japan there are a number of children and adolescents with emotion-related disorders including psychosomatic diseases (orthostatic dysregulation, anorexia nervosa, recurrent pains, behavior problems and school absenteeism. According to our previous report, the Japanese children had significantly higher score of physical symptoms and psychiatric complaints than did the Swedish children, and these were more strongly influenced by school-related stress than by home-related stress. To enforce countermeasures for psychosomatic problems in children, the Japanese Society of Psychosomatic Pediatrics (established in 1982 have started several new projects including multi-center psychosomatic researches and society-based activities. In this article, we present an outline of our study on mental health in Japanese children in comparison with Swedish children. Countermeasures including clinical guidelines for child psychosomatic diseases are reviewed and discussed.

  11. Countermeasure technology for environmental pollution due to radioactive substances

    This paper introduces the progress of challenges by Maeda Corporation toward the countermeasures for the environmental pollution caused by radioactive substances that covers the whole areas of Naraha Town in Fukushima Prefecture. It also introduces in full detail the environmental pollution countermeasure technologies against radioactive substances challenged by the said company. These technologies are as follows; (1) porous block kneaded with zeolite, (2) Aqua-filter System (technique to automatically and continuously purify construction work water to the level of tap water), (3) super vacuum press (dehydration unit to realize the dehydration, volume reduction and solidification, and insolubilization at the same time), (4) mist blender (technique to manufacture bentonite-mixed soil), (5) wet-type classification washing technique for contaminated soil, (6) soil sorting technique (continuous discrimination technique to sort soil depending on radiation level), and (7) speedy construction technique for dam body using CSG (cemented sand and gravel). (A.O.)

  12. Improvement of practical Countermeasures: Preventive medication. Post-Chernobyl action

    The Chernobyl accident, which occurred on 26 April 1986, presented major challenges to the European Community with respect to the practical and regulatory aspects of radiation protection, public information, trade, particularly in food, and international politics. The Chernobyl accident was also a major challenge to the international scientific community which had to evaluate rapidly the radiological consequences of the accident and advise on the introduction of any countermeasures. Prior to the accident at Chernobyl, countermeasures to reduce the consequences of radioactive contamination had been conceived largely in the context of relatively small accidental releases and for application over relatively small areas. Less consideration had been given to the practical implications of applying such measures in case of a large source term and a spread over a very large area

  13. Information hiding in communication networks fundamentals, mechanisms, applications, and countermeasures

    Mazurczyk, Wojciech; Zander, Sebastian; Houmansadr, Amir; Szczypiorski, Krzysztof

    2016-01-01

    Describes Information Hiding in communication networks, and highlights their important issues, challenges, trends, and applications. This book provides the fundamental concepts, terminology, and classifications of information hiding in communication networks along with its historical background. Information Hiding In Communication Networks: Fundamentals, Mechanisms, Applications, and Countermeasures begins with introducing data concealment methods and their evolution. Chapter two discusses the existing terminology and describes the model for hidden communication and related communication scenarios. Chapters three to five present the main classes of information hiding in communication networks accompanied by a discussion of their robustness and undetectability. The book concludes with a discussion of potential countermeasures against information hiding techniques, which includes different types of mechanisms for the detection, limitation and prevention of covert co munication channels.

  14. Radioactivity and countermeasures like clean feeding of sheep

    It's been 25 years since the nuclear accident at Chernobyl, but there is still radioactivity remaining in the Norwegian nature. The radioactive cesium-137 is taken up by plants and fungi and transferred to animals on rangelands. In the grazing season of 2010 had 20 000 sheep on Countermeasures like clean feeding to reduce radioactivity levels in the meat before slaughter. Oppland had most sheep on Countermeasures like clean feeding with almost 12 000 animals. Total was paid 2.2 million in compensation to livestock owners in 2010. In the period 1986-2010 is about 2.2 million sheep have been suspended with a charge of approximately NOK 227 million. (AG)

  15. Behaviour of radionuclides in meadows and efficiency of countermeasures

    The behaviour of radionuclides and the efficiency of countermeasures were dependent on meadow type. The migration of 137Cs proceeds much more slowly in the soil profile on dry meadows than on peatlands and flooded land. The half-life of 137Cs in the root zone changes from 10 to 25 years. The highest transfer factors in grasslands are obtained for peaty lands and flooded meadows, and minimal ones for dry meadows. The first half-life of 137Cs transfer to plants changes from 2.0 to 2.2 years and the second (slower) half-life changes from 4.0 to 12 years for different meadow types. The countermeasure efficiency in meadows varied from 1.2 to 10.0. (Author)

  16. Harmful and Needless Emission of Refrigerant and Countermeasures

    Wu Zeqiu

    2009-01-01

    Refrigerants used in refrigerators are an important source of ozone depleting substances released into the atmosphere,and can have a significantly negative effect on the hole in the ozone layer.But most emission of refrigerants is man-made,unreasonable and needless.Since in most emission cases the refrigerants are contained in the refrigerators,we can retrieve them by some technique that changes the 'manual emission' into manual retrieving.To promote the retrieval action and diminish the pollution,society can use economic,administrative and technical countermeasures,which can create a 'good-cycle' both 'harnessing pollution and earning income simultaneously',reinforce the motive of retrieving,and retrieve most proportion of refrigerants used by all refrigerators.This 'good-cycle' method can be easily promoted,and also a valuable way to promote other forms of environmental protection.The three countermeasures have almost no social cost,even no cost at all.

  17. The countermeasures against the blinding attack in quantum key distribution

    Wang, Jindong; Wang, Hong; Qin, Xiaojuan; Wei, Zhengjun; Zhang, Zhiming

    2016-01-01

    It has been shown that the single photon detectors (SPDs) based on the avalanche photodiode (APD) can be blinded and controlled by the bright light and short trigger pulses. Eavesdropper can get the full information without causing additional quantum bit error rate. Hence, in order to guarantee the security of the quantum key distribution (QKD) systems, some countermeasures, by changing the characteristic of the SPD or monitoring the parameters of the detector, are presented by some research groups. In this paper, we provide a new and effective countermeasure against the blinding attack based on improving the optical scheme of the decoding unit in the QKD system rather than only considering the characteristic of the SPD. In our proposal we use a coupler with asymmetric splitting ratio to distinguish the detection characteristic of the SPD with blinding attack from that without blinding attack. The detailed analysis shows that the proposed scheme is feasible to defense the blinding attack.

  18. Acoustically enhanced heat transport

    Ang, Kar M.; Hung, Yew Mun; Tan, Ming K., E-mail: tan.ming.kwang@monash.edu [School of Engineering, Monash University Malaysia, 47500 Bandar Sunway, Selangor (Malaysia); Yeo, Leslie Y. [Micro/Nanophysics Research Laboratory, RMIT University, Melbourne, VIC 3001 (Australia); Friend, James R. [Department of Mechanical and Aerospace Engineering, University of California, San Diego, California 92093 (United States)

    2016-01-15

    We investigate the enhancement of heat transfer in the nucleate boiling regime by inducing high frequency acoustic waves (f ∼ 10{sup 6} Hz) on the heated surface. In the experiments, liquid droplets (deionized water) are dispensed directly onto a heated, vibrating substrate. At lower vibration amplitudes (ξ{sub s} ∼ 10{sup −9} m), the improved heat transfer is mainly due to the detachment of vapor bubbles from the heated surface and the induced thermal mixing. Upon increasing the vibration amplitude (ξ{sub s} ∼ 10{sup −8} m), the heat transfer becomes more substantial due to the rapid bursting of vapor bubbles happening at the liquid-air interface as a consequence of capillary waves travelling in the thin liquid film between the vapor bubble and the air. Further increases then lead to rapid atomization that continues to enhance the heat transfer. An acoustic wave displacement amplitude on the order of 10{sup −8} m with 10{sup 6} Hz order frequencies is observed to produce an improvement of up to 50% reduction in the surface temperature over the case without acoustic excitation.

  19. Detection and tracking of drones using advanced acoustic cameras

    Busset, Joël.; Perrodin, Florian; Wellig, Peter; Ott, Beat; Heutschi, Kurt; Rühl, Torben; Nussbaumer, Thomas

    2015-10-01

    Recent events of drones flying over city centers, official buildings and nuclear installations stressed the growing threat of uncontrolled drone proliferation and the lack of real countermeasure. Indeed, detecting and tracking them can be difficult with traditional techniques. A system to acoustically detect and track small moving objects, such as drones or ground robots, using acoustic cameras is presented. The described sensor, is completely passive, and composed of a 120-element microphone array and a video camera. The acoustic imaging algorithm determines in real-time the sound power level coming from all directions, using the phase of the sound signals. A tracking algorithm is then able to follow the sound sources. Additionally, a beamforming algorithm selectively extracts the sound coming from each tracked sound source. This extracted sound signal can be used to identify sound signatures and determine the type of object. The described techniques can detect and track any object that produces noise (engines, propellers, tires, etc). It is a good complementary approach to more traditional techniques such as (i) optical and infrared cameras, for which the object may only represent few pixels and may be hidden by the blooming of a bright background, and (ii) radar or other echo-localization techniques, suffering from the weakness of the echo signal coming back to the sensor. The distance of detection depends on the type (frequency range) and volume of the noise emitted by the object, and on the background noise of the environment. Detection range and resilience to background noise were tested in both, laboratory environments and outdoor conditions. It was determined that drones can be tracked up to 160 to 250 meters, depending on their type. Speech extraction was also experimentally investigated: the speech signal of a person being 80 to 100 meters away can be captured with acceptable speech intelligibility.

  20. Optimization of massive countermeasure design in complex rockfall settings

    Agliardi, Federico; Crosta, Giovanni B.

    2015-04-01

    Rockfall protection is a major need in areas impended by subvertical rockwalls with complex 3D morphology and little or no talus to provide natural rockfall attenuation. The design of massive embankments, usually required to ensure such protection, is particularly difficult in complex rockfall settings, due to: widespread occurrence of rockfall sources; difficult characterization of size distribution and location of unstable volumes; variability of failure mechanisms; spatial scattering of rockfall trajectories; high expected kinetic energies. Moreover, rockwalls in complex lithological and structural settings are often prone to mass falls related to rock mass sector collapses. All these issues may hamper a safe application of classic embankment analysis approaches, using empirical rules or 2D-based height/energy statistics, and point to the need of integrated analyses of rock slope instability and rockfall runout in 3D. We explore the potential of combining advanced rock mass characterisation techniques and 3D rockfall modelling to support challenging countermeasure design at a site near Lecco (Southern Alps, Italy). Here subvertical cliffs up to 600 m high impend on a narrow (global) failure mechanisms for different slope sectors. This information provided improved spatially-distributed inputs to 3D rockfall runout modelling, performed using the Hy_STONE rockfall simulator and explicitly integrating the countermeasure design geometry into a HRDEM. We calibrated modelling parameters by the back analysis of previous rockfalls and performed predictive simulations accounting for different landslide size scenarios. Countermeasure design was verified according to the spatial pattern, height and overpassing probability of expected trajectories, allowing the evaluation of three 'countermeasure efficiency descriptors' to be used for design optimisation scenarios.

  1. Research on Risks and Forecasting Countermeasures of Hainan Banana Industry

    Liu, Yan-qun; Zeng, Xiao-hong; Fang, Jia

    2011-01-01

    Based on the overviews of the current conditions of Hainan banana industry, the research makes an analysis of the risks faced by Hainan banana industry. They are respectively marketing risks, natural risks, information risks and production risks. In order to promote a sustainable and rapid development of Hainan banana industry, Countermeasures are proposed in the research. The first is to strengthen the leading organization of forecasting mechanisms on banana industry. The second is to establ...

  2. Problems in Food Safety of Hunan Province and Countermeasures

    OUYANG, Fanfan; Deng, Fangming

    2014-01-01

    In recent years, serious food safety accidents are of frequent occurrence. Although government has taken many practical and feasible measures to contain food safety accidents, new food safety accidents still emerge in large numbers. In this situation, food safety control is a long-term and arduous task to be performed jointly by many government departments. Finally, it presents corresponding countermeasures and recommendations on the basis of current situations of food safety in Hunan Provinc...

  3. Bottleneck on Supply Chain of Organic Agricultural Products and Countermeasures

    ZHANG Xin-min

    2012-01-01

    Organic agriculture is one of successful models of low-carbon agriculture, and plays an important role in alleviating and adapting to climate change. However, the development of supply chain of organic agricultural products lags behind, which seriously restricts development of organic agricultural product market. In this paper, major models and bottleneck of supply chain of organic agricultural products are analyzed, and finally countermeasures are put forward.

  4. Artificial gravity intermittent centrifugation as a space flight countermeasure

    Vernikos, J.

    1997-01-01

    Head-down bed rest was used to simulate weightlessness in an experiment that examined variations in dose, time, and frequency of +Gz stimuli countermeasures. Results indicate that 4 hr. standing was most effective for orthostatic intolerance, walking was most effective in achieving peak oxygen consumption, 4 hr. of standing or walking had the best effect on plasma volume, and 4 hr. of walking was most effective in maintaining urinary calcium excretion.

  5. Password Cracking and Countermeasures in Computer Security: A Survey

    Han, Aaron L. -F.; Wong, Derek F.; Chao, Lidia S.

    2014-01-01

    With the rapid development of internet technologies, social networks, and other related areas, user authentication becomes more and more important to protect the data of the users. Password authentication is one of the widely used methods to achieve authentication for legal users and defense against intruders. There have been many password cracking methods developed during the past years, and people have been designing the countermeasures against password cracking all the time. However, we fi...

  6. Current Situation and Countermeasures of Rural Primary School English Teaching

    吴国良

    2014-01-01

    The promotion of rural primary schools in English and open, influenced by many factors, there are many problems, making the rural and urban pupils compared to the poor standard of English is great, even when individual students graduated from elementary school even 26 English letters are read incomplete or pronunciation, this article will explain the status quo and countermeasures of teaching English in primary schools in rural areas.

  7. Current Situation and Countermeasures for Green Electricity in Shanghai

    Zhang Rui; Gao Yang

    2007-01-01

    @@ The present situation of the green electricity in Shanghai is briefly introduced. The author analyzes various advantages in natural environment, market environment and social environment as well as various disadvantages in the respects of cost, price, economy for Shanghai to develop green electricity. It is pointed out that governments, non-government organizations, consumers and enterprises shall jointly make efforts to promote the green electricity in Shanghai. Finally,concrete countermeasures and suggestions are put forward.

  8. Risk and Business Goal Based Security Requirement and Countermeasure Prioritization

    Herrmann, Andrea; Morali, Ayse; Etalle, Sandro; Wieringa, Roel

    2012-01-01

    Companies are under pressure to be in control of their assets but at the same time they must operate as efficiently as possible. This means that they aim to implement “good-enough security” but need to be able to justify their security investment plans. Currently companies achieve this by means of checklist-based security assessments, but these methods are a way to achieve consensus without being able to provide justifications of countermeasures in terms of business goals. But such justificat...

  9. Exercise Countermeasure Hardware Evolution on ISS: The First Decade.

    Korth, Deborah W

    2015-12-01

    The hardware systems necessary to support exercise countermeasures to the deconditioning associated with microgravity exposure have evolved and improved significantly during the first decade of the International Space Station (ISS), resulting in both new types of hardware and enhanced performance capabilities for initial hardware items. The original suite of countermeasure hardware supported the first crews to arrive on the ISS and the improved countermeasure system delivered in later missions continues to serve the astronauts today with increased efficacy. Due to aggressive hardware development schedules and constrained budgets, the initial approach was to identify existing spaceflight-certified exercise countermeasure equipment, when available, and modify it for use on the ISS. Program management encouraged the use of commercial-off-the-shelf (COTS) hardware, or hardware previously developed (heritage hardware) for the Space Shuttle Program. However, in many cases the resultant hardware did not meet the additional requirements necessary to support crew health maintenance during long-duration missions (3 to 12 mo) and anticipated future utilization activities in support of biomedical research. Hardware development was further complicated by performance requirements that were not fully defined at the outset and tended to evolve over the course of design and fabrication. Modifications, ranging from simple to extensive, were necessary to meet these evolving requirements in each case where heritage hardware was proposed. Heritage hardware was anticipated to be inherently reliable without the need for extensive ground testing, due to its prior positive history during operational spaceflight utilization. As a result, developmental budgets were typically insufficient and schedules were too constrained to permit long-term evaluation of dedicated ground-test units ("fleet leader" type testing) to identify reliability issues when applied to long-duration use. In most cases

  10. Determination of Sample Sizes for Demonstrating Efficacy of Radiation Countermeasures

    Kodell, Ralph L; Lensing, Shelly Y; Landes, Reid D.; Kumar, K. Sree; Hauer-Jensen, Martin

    2009-01-01

    In response to the ever increasing threat of radiological and nuclear terrorism, active development of non-toxic new drugs and other countermeasures to protect against and/or mitigate adverse health effects of radiation is ongoing. Although the classical LD50 study used for many decades as a first step in preclinical toxicity testing of new drugs has been largely replaced by experiments that use fewer animals, the need to evaluate the radioprotective efficacy of new drugs necessitates the con...

  11. Virtualisation-Based Security Countermeasures in Software Runtime Systems

    Gadaleta, Francesco

    2013-01-01

    As systems become larger and more complex, the need to optimise the infrastructure in favour of reliability and redundancy becomes an imperative. Virtualisation technology seems to have partially fulfilled the needs dictated by growth by redefining the concept of infrastructure and paving the way for new business models such as cloud computing. As a matter of fact, successful low level attacks can circumvent or disable many of the traditional countermeasures in place within the same target sy...

  12. Fluxes of radiocesium to milk and appropriate countermeasures

    Radiocesium contamination of milk persists in some areas of Belarus, Ukraine and Russian Federation which received fallout from the Chernobyl accident. In general, effective countermeasures have been used which ensure that radiocesium activity concentrations in milk from collective farms does not exceed intervention limits. However, farming practices differ greatly between the large collective farms, and the small, family operated private farms which are responsible for a major part of the food consumed in many rural areas. As a result of comparative low rate of use of fertilizers and utilization of poor quality land 137Cs activity concentrations in milk from family-owned cows continues to exceed intervention limits in some areas. It is therefore important to be able reliably to quantify the rates of transfer of 137Cs to private milk, so that all areas where persistent problems occur are identified, and appropriate countermeasure strategies applied. Where there is considerable variation, within a few km2, in both soil type and deposition, the 137Cs content of private milk is highly variable. However, combining information about soil type, transfer rates for each major soil type, deposition, pasture size and grazing strategies can be a useful method of quantifying transfer of radiocesium to milk. Geographical information systems provide a promising new tool to integrate these factors. Effective Countermeasures are available to reduce radiocesium transfer to private milk. Private farmers are more sceptical of such methods than the scientists, administrators and agriculturalists in their society, particularly those methods involving the use of chemical additives given to their animals. Increased information efforts on the local level appears to be a prerequisite for a successful implementation of necessary Countermeasures

  13. The Problems and its Countermeasures of Autonomous Language Learning Center

    NIE Jian-feng

    2014-01-01

    With the popularity of Computer Assisted Language Learning (CALL), autonomous language learning centers have been established in the universities throughout the country. However, there are many problems exist in the practice of the auton-omous language learning center. This essay tries to discuss the problems and its countermeasures with an aim of improving Col-lege English learning and teaching by the example of autonomous language learning center in Nanyang Institute of Technology.

  14. Assessment of Countermeasure Efficacy for Long-Term Space Missions

    Feiveson, Alan H.; Paloski, William H. (Technical Monitor)

    2000-01-01

    One of the main functions of the upcoming International Space Station (ISS) will be to provide a venue for testing proposed countermeasures for their ability to protect humans from the debilitating effects of longterm space flight. However, several limiting factors preclude an evaluation process similar to that used in clinical trials which traditionally are implemented with large sample sizes of subjects, including control groups, and with blind or double-blind application of treatments according to factorial or other balanced experimental designs. In particular, only very limited numbers of human subjects will be available for actual field testing in the ISS With no more than 125 subjects planned to fly on all ISS missions over 10 years, it is not possible to test extensive combinations of some 15-20 proposed countermeasures. Furthermore because of safety concerns and operational considerations, it is unlikely that anything other than the current best guess at the most effective countermeasure package will ever be used on ISS. In particular, control or placebos will not be allowed. In view of these limitations, historical data and groundbased or animal studies will have to be used to compensate for small sample sizes and lack of controls in the field. As a result, statistical analysis methodology will have to be developed which allows for the integration of these disparate data types into a meaningful evaluation process. The process must be sequential, providing objective rules for deciding through time whether to reject or modify an ineffective countermeasure, or whether to certify one as effective. Additional output should include performance characteristics for all relevant physiological systems, including uncertainty analyses and estimates of accept/reject decision error rates.

  15. Challenges of Animal Derived Food Safety and Counter-measures

    Yeping Tan; Changhua Lu; Yinong Hu

    2014-01-01

    The safety of animal derived food has been at the forefront of societal concerns in recent years. In this paper, we stress major animal derived food issues and challenges including microbial pathogens, food additives and chemical residues. In addition, the countermeasures to animal derived food issues including animal health and welfare, animal identification and traceability, antimicrobial interventions, new processes and technologies in the processing and preservation of animal derived food...

  16. Challenges of Animal Derived Food Safety and Counter-measures

    Yeping Tan

    2014-04-01

    Full Text Available The safety of animal derived food has been at the forefront of societal concerns in recent years. In this paper, we stress major animal derived food issues and challenges including microbial pathogens, food additives and chemical residues. In addition, the countermeasures to animal derived food issues including animal health and welfare, animal identification and traceability, antimicrobial interventions, new processes and technologies in the processing and preservation of animal derived food products, and Risk assessment are discussed.

  17. Obstacles to Rural Residents' Consumption in China and the Countermeasures

    Huang, Yi

    2011-01-01

    On the basis of relevant statistical data, this paper analyzes the obstacles to rural residents' consumption in China as follows, the consumption structure is restricted critically; the consumption environment cannot meet the need of social development; the traditional consumption concept has not yet been changed; the social security system is not sound; the support of rural finance is short. Pointed countermeasures for eliminating the obstacles to rural residents' consumption are put forward...

  18. Preventive countermeasures for transient stability-constrained power systems

    Ruiz-Vega, Daniel; Ernst, Damien; Pavella, Mania

    2000-01-01

    A general transient stability control technique is applied to the design of preventive countermeasures consisting of rescheduling generators’ active power. The technique relies on SIME, a hybrid direct–time-domain method; and, like SIME, it preserves the accuracy of time-domain methods and their ability to handle any power system modeling, stability scenario and mode of instability. Its application to generation rescheduling may provide various patterns, able to comply with various operationa...

  19. Research on Development Status and Countermeasures of Agricultural Cleaner Production

    2011-01-01

    In the study,the connotation and objectives of agricultural cleaner production were introduced firstly,and then the development status of agricultural cleaner production in China was analyzed,and the problems existing in the development of agricultural cleaner production were pointed out.From the strategy of agricultural sustainable development,the necessity and feasibility of implementing agricultural cleaner production in China were discussed.Finally,some related countermeasures were put forward according...

  20. Latest Trends in Acoustic Sensing

    Cinzia Caliendo

    2014-03-01

    Full Text Available Acoustics-based methods offer a powerful tool for sensing applications. Acoustic sensors can be applied in many fields ranging from materials characterization, structural health monitoring, acoustic imaging, defect characterization, etc., to name just a few. A proper selection of the acoustic wave frequency over a wide spectrum that extends from infrasound (<20 Hz up to ultrasound (in the GHz–band, together with a number of different propagating modes, including bulk longitudinal and shear waves, surface waves, plate modes, etc., allow acoustic tools to be successfully applied to the characterization of gaseous, solid and liquid environments. The purpose of this special issue is to provide an overview of the research trends in acoustic wave sensing through some cases that are representative of specific applications in different sensing fields.

  1. High-Frequency Seafloor Acoustics

    Jackson, Darrell R

    2007-01-01

    High-Frequency Seafloor Acoustics is the first book in a new series sponsored by the Office of Naval Research on the latest research in underwater acoustics. This exciting new title provides ready access to experimental data, theory, and models relevant to high-frequency seafloor acoustics and will be of interest to sonar engineers and researchers working in underwater acoustics. The physical characteristics of the seafloor affecting acoustic propagation and scattering are covered, including physical and geoacoustic properties and surface roughness. Current theories for acoustic propagation in sediments are presented along with corresponding models for reflection, scattering, and seafloor penetration. The main text is backed up by an extensive bibliography and technical appendices.

  2. Fundamentals of Shallow Water Acoustics

    Katsnelson, Boris; Lynch, James

    2012-01-01

    Shallow water acoustics (SWA), the study of how low and medium frequency sound propagates and scatters on the continental shelves of the world's oceans, has both technical interest and a large number of practical applications. Technically, shallow water poses an interesting medium for the study of acoustic scattering, inverse theory, and propagation physics in a complicated oceanic waveguide. Practically, shallow water acoustics has interest for geophysical exploration, marine mammal studies, and naval applications. Additionally, one notes the very interdisciplinary nature of shallow water acoustics, including acoustical physics, physical oceanography, marine geology, and marine biology. In this specialized volume, the authors, all of whom have extensive at-sea experience in U.S. and Russian research efforts, have tried to summarize the main experimental, theoretical, and computational results in shallow water acoustics, with an emphasis on providing physical insight into the topics presented.

  3. Information Overload and Viral Marketing: Countermeasures and Strategies

    Cheng, Jiesi; Sun, Aaron; Zeng, Daniel

    Studying information diffusion through social networks has become an active research topic with important implications in viral marketing applications. One of the fundamental algorithmic problems related to viral marketing is the Influence Maximization (IM) problem: given an social network, which set of nodes should be considered by the viral marketer as the initial targets, in order to maximize the influence of the advertising message. In this work, we study the IM problem in an information-overloaded online social network. Information overload occurs when individuals receive more information than they can process, which can cause negative impacts on the overall marketing effectiveness. Many practical countermeasures have been proposed for alleviating the load of information on recipients. However, how these approaches can benefit viral marketers is not well understood. In our work, we have adapted the classic Information Cascade Model to incorporate information overload and study its countermeasures. Our results suggest that effective control of information overload has the potential to improve marketing effectiveness, but the targeting strategy should be re-designed in response to these countermeasures.

  4. Public acceptance and assessment of countermeasures after the Chernobyl accident

    General Background. Previous studies confirmed that the main reason of the psychological stress after Chernobyl was a worry about radiation influence on personal health and health of children. This ''Chernobyl stress'' is typical ''information'' or emotional stress resulting from mass media information on radioactive contamination and exposure but not from direct personal visual or auditory and other impression for 5 million population. The population was not able to define the radiation danger by direct sensual perception without measuring equipment but was obliged to change their life-style and diet as a remedial action and to follow the radiation protection requirements and advices. Therefore the anxiety was related not only to information about the accident but also to implemental countermeasures, which changed the everyday life. The countermeasures became the first real sign of the accident. Methods. In 1988-1994 studies based on population interview of about 5 thousand residents and questionnaires were carried out on contaminated (15 - 40 Ci/km2) territories, adjacent and distant areas. The following information was used: population knowledge of protective measures; sources of information about radiation and level of trust; assessment of the effectiveness and reasons of non-satisfaction of the protection measures; compliance and involvement of population in countermeasures including effects of life-style changes and behavior; public opinion on priority for financial expenditure for mitigation of accident consequences

  5. Efficacy of radiation countermeasures depends on radiation quality.

    Cary, Lynnette H; Ngudiankama, Barbara F; Salber, Rudolph E; Ledney, G David; Whitnall, Mark H

    2012-05-01

    The detonation of a nuclear weapon or a nuclear accident represent possible events with significant exposure to mixed neutron/γ-radiation fields. Although radiation countermeasures generally have been studied in subjects exposed to pure photons (γ or X rays), the mechanisms of injury of these low linear energy transfer (LET) radiations are different from those of high-LET radiation such as neutrons, and these differences may affect countermeasure efficacy. We compared 30-day survival in mice after varying doses of pure γ and mixed neutron/γ (mixed field) radiation (MF, Dn/Dt = 0.65), and also examined peripheral blood cells, bone marrow cell reconstitution, and cytokine expression. Mixed-field-irradiated mice displayed prolonged defects in T-cell populations compared to mice irradiated with pure γ photons. In mouse survival assays, the growth factor granulocyte colony-stimulating factor (G-CSF) was effective as a (post-irradiation) mitigator against both γ-photons and mixed-field radiation, while the thrombopoietin (TPO) mimetic ALXN4100TPO was effective only against γ irradiation. The results indicate that radiation countermeasures should be tested against radiation qualities appropriate for specific scenarios before inclusion in response plans. PMID:22468705

  6. Wireless Acoustic Measurement System

    Anderson, Paul D.; Dorland, Wade D.; Jolly, Ronald L.

    2007-01-01

    A prototype wireless acoustic measurement system (WAMS) is one of two main subsystems of the Acoustic Prediction/ Measurement Tool, which comprises software, acoustic instrumentation, and electronic hardware combined to afford integrated capabilities for predicting and measuring noise emitted by rocket and jet engines. The other main subsystem is described in the article on page 8. The WAMS includes analog acoustic measurement instrumentation and analog and digital electronic circuitry combined with computer wireless local-area networking to enable (1) measurement of sound-pressure levels at multiple locations in the sound field of an engine under test and (2) recording and processing of the measurement data. At each field location, the measurements are taken by a portable unit, denoted a field station. There are ten field stations, each of which can take two channels of measurements. Each field station is equipped with two instrumentation microphones, a micro- ATX computer, a wireless network adapter, an environmental enclosure, a directional radio antenna, and a battery power supply. The environmental enclosure shields the computer from weather and from extreme acoustically induced vibrations. The power supply is based on a marine-service lead-acid storage battery that has enough capacity to support operation for as long as 10 hours. A desktop computer serves as a control server for the WAMS. The server is connected to a wireless router for communication with the field stations via a wireless local-area network that complies with wireless-network standard 802.11b of the Institute of Electrical and Electronics Engineers. The router and the wireless network adapters are controlled by use of Linux-compatible driver software. The server runs custom Linux software for synchronizing the recording of measurement data in the field stations. The software includes a module that provides an intuitive graphical user interface through which an operator at the control server

  7. Magneto-photo-acoustic imaging

    Qu, Min; Mallidi, Srivalleesha; Mehrmohammadi, Mohammad; Truby, Ryan; Homan, Kimberly; Joshi, Pratixa; Chen, Yun-Sheng; Sokolov, Konstantin; Emelianov, Stanislav

    2011-01-01

    Magneto-photo-acoustic imaging, a technique based on the synergy of magneto-motive ultrasound, photoacoustic and ultrasound imaging, is introduced. Hybrid nanoconstructs, liposomes encapsulating gold nanorods and iron oxide nanoparticles, were used as a dual-contrast agent for magneto-photo-acoustic imaging. Tissue-mimicking phantom and macrophage cells embedded in ex vivo porcine tissue were used to demonstrate that magneto-photo-acoustic imaging is capable of visualizing the location of cel...

  8. Room acoustic auralization with Ambisonics

    Polack, Jean-Dominique; Leão Figueiredo, Fábio

    2012-01-01

    International audience During the year of 2009, the room acoustics group of the LAM (Équipe Lutheries, Acoustique, Musique de l’Institut Jean Le Rond d’Alembert - Université Pierre et Marie Curie, Paris) performed a series of acoustical measurements in music halls in Paris. The halls were chosen in regarding their importance to the historic, architectural or acoustic domains. The measured ensemble of fourteen rooms includes quite different architectural designs. The measurements were carri...

  9. Truck acoustic data analyzer system

    Haynes, Howard D.; Akerman, Alfred; Ayers, Curtis W.

    2006-07-04

    A passive vehicle acoustic data analyzer system having at least one microphone disposed in the acoustic field of a moving vehicle and a computer in electronic communication the microphone(s). The computer detects and measures the frequency shift in the acoustic signature emitted by the vehicle as it approaches and passes the microphone(s). The acoustic signature of a truck driving by a microphone can provide enough information to estimate the truck speed in miles-per-hour (mph), engine speed in rotations-per-minute (RPM), turbocharger speed in RPM, and vehicle weight.

  10. Combined Environment Acoustic Chamber (CEAC)

    Federal Laboratory Consortium — Purpose: The CEAC imposes combined acoustic, thermal and mechanical loads on aerospace structures. The CEAC is employed to measure structural response and determine...

  11. Acoustic transparency and slow sound using detuned acoustic resonators

    Santillan, Arturo Orozco; Bozhevolnyi, Sergey I.

    2011-01-01

    We demonstrate that the phenomenon of acoustic transparency and slowsound propagation can be realized with detuned acoustic resonators (DAR), mimicking thereby the effect of electromagnetically induced transparency (EIT) in atomic physics. Sound propagation in a pipe with a series of side...

  12. Ares I Scale Model Acoustic Test Lift-Off Acoustics

    Counter, Douglas D.; Houston, Janie D.

    2011-01-01

    The lift-off acoustic (LOA) environment is an important design factor for any launch vehicle. For the Ares I vehicle, the LOA environments were derived by scaling flight data from other launch vehicles. The Ares I LOA predicted environments are compared to the Ares I Scale Model Acoustic Test (ASMAT) preliminary results.

  13. Acoustic Mechanical Feedthroughs

    Sherrit, Stewart; Walkemeyer, Phillip; Bao, Xiaoqi; Bar-Cohen, Yoseph; Badescu, Mircea

    2013-01-01

    Electromagnetic motors can have problems when operating in extreme environments. In addition, if one needs to do mechanical work outside a structure, electrical feedthroughs are required to transport the electric power to drive the motor. In this paper, we present designs for driving rotary and linear motors by pumping stress waves across a structure or barrier. We accomplish this by designing a piezoelectric actuator on one side of the structure and a resonance structure that is matched to the piezoelectric resonance of the actuator on the other side. Typically, piezoelectric motors can be designed with high torques and lower speeds without the need for gears. One can also use other actuation materials such as electrostrictive, or magnetostrictive materials in a benign environment and transmit the power in acoustic form as a stress wave and actuate mechanisms that are external to the benign environment. This technology removes the need to perforate a structure and allows work to be done directly on the other side of a structure without the use of electrical feedthroughs, which can weaken the structure, pipe, or vessel. Acoustic energy is pumped as a stress wave at a set frequency or range of frequencies to produce rotary or linear motion in a structure. This method of transferring useful mechanical work across solid barriers by pumping acoustic energy through a resonant structure features the ability to transfer work (rotary or linear motion) across pressure or thermal barriers, or in a sterile environment, without generating contaminants. Reflectors in the wall of barriers can be designed to enhance the efficiency of the energy/power transmission. The method features the ability to produce a bi-directional driving mechanism using higher-mode resonances. There are a variety of applications where the presence of a motor is complicated by thermal or chemical environments that would be hostile to the motor components and reduce life and, in some instances, not be

  14. Dynamic acoustic tractor beams

    Mitri, F. G.

    2015-03-01

    Pulling a sphere and vibrating it around an equilibrium position by amplitude-modulation in the near-field of a single finite circular piston transducer is theoretically demonstrated. Conditions are found where a fluid hexane sphere (with arbitrary radius) chosen as an example, centered on the axis of progressive propagating waves and submerged in non-viscous water, experiences an attractive (steady) force pulling it towards the transducer, as well as an oscillatory force forcing it to vibrate back-and-forth. Numerical predictions for the dynamic force illustrate the theory and suggest an innovative method in designing dynamic acoustical tractor beams.

  15. Dynamic acoustic tractor beams

    Mitri, F. G., E-mail: F.G.Mitri@ieee.org [Chevron, Area 52 Technology – ETC, Santa Fe, New Mexico 87508 (United States)

    2015-03-07

    Pulling a sphere and vibrating it around an equilibrium position by amplitude-modulation in the near-field of a single finite circular piston transducer is theoretically demonstrated. Conditions are found where a fluid hexane sphere (with arbitrary radius) chosen as an example, centered on the axis of progressive propagating waves and submerged in non-viscous water, experiences an attractive (steady) force pulling it towards the transducer, as well as an oscillatory force forcing it to vibrate back-and-forth. Numerical predictions for the dynamic force illustrate the theory and suggest an innovative method in designing dynamic acoustical tractor beams.

  16. Taming Acoustic Cavitation

    Rivas, David Fernandez; Enriquez, Oscar R; Versluis, Michel; Prosperetti, Andrea; Gardeniers, Han; Lohse, Detlef

    2012-01-01

    In this fluid dynamics video we show acoustic cavitation occurring from pits etched on a silicon surface. By immersing the surface in a liquid, gas pockets are entrapped in the pits which upon ultrasonic insonation, are observed to shed cavitation bubbles. Modulating the driving pressure it is possible to induce different behaviours based on the force balance that determines the interaction among bubbles and the silicon surface. This system can be used for several applications like sonochemical water treatment, cleaning of surfaces with deposited materials such as biofilms.

  17. Lecture Notes On Acoustics

    This book mentions string vibration and wave, one-dimension wave and wave equation, characteristic impedance, governing equation of string, and wave energy from string, wave equation of wave and basic physical quantity like one-dimension wave equation, sound unit, sound intensity and energy, sound movement in a surface of discontinuity with transmission loss of sound by partition, and Snell's law, radiation, scatter and diffraction and sound in closed space with Sabine's theory, sound characteristic of closed space and duct acoustics.

  18. 76 FR 71982 - Advancing Regulatory Science for Highly Multiplexed Microbiology/Medical Countermeasure Devices...

    2011-11-21

    ... Regulatory Science for Highly Multiplexed Microbiology/ Medical Countermeasure Devices'' that published in the Federal Register of August 8, 2011 (76 FR 48169). In the notice, FDA requested public comments... Microbiology/ Medical Countermeasure Devices; Public Meeting; Reopening of Comment Period AGENCY: Food and...

  19. Digital Controller For Acoustic Levitation

    Tarver, D. Kent

    1989-01-01

    Acoustic driver digitally controls sound fields along three axes. Allows computerized acoustic levitation and manipulation of small objects for such purposes as containerless processing and nuclear-fusion power experiments. Also used for controlling motion of vibration-testing tables in three dimensions.

  20. Acoustic Metamaterials and Phononic Crystals

    2013-01-01

    This comprehensive book presents all aspects of acoustic metamaterials and phononic crystals. The emphasis is on acoustic wave propagation phenomena at interfaces such as refraction, especially unusual refractive properties and negative refraction. A thorough discussion of the mechanisms leading to such refractive phenomena includes local resonances in metamaterials and scattering in phononic crystals.

  1. Acoustic engineering and technology '90

    Acoustic monitoring, testing and diagnosis in machines, production processes and products enhance the uptimes and profitability of machinery and plants. 18 papers discuss the current state of the art of acoustic monitoring systems including integrated factory planning as well as industrial health, and noise protection. (DG)

  2. Acoustic Center or Time Origin?

    Staffeldt, Henrik

    1999-01-01

    The paper discusses the acoustic center in relation to measurements of loudspeaker polar data. Also, it presents the related concept time origin and discusses the deviation that appears between positions of the acoustic center found by wavefront based and time based measuring methods....

  3. Propagation of Ion Acoustic Perturbations

    Pécseli, Hans

    1975-01-01

    Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered.......Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered....

  4. International Short-Term Countermeasures Survey - 2012 Update

    Nuclear emergency planning, preparedness, response, and management, in general, are essential elements of any country's nuclear power programme. Part of nuclear emergency planning and preparedness is the implementation of national emergency plans, including detailed procedures for the implementation of short-term countermeasures, before during, and after the release of radioactive substances. The timely and appropriate implementation of short-term countermeasures, such as sheltering, evacuation, and iodine prophylaxis, can, in case of a nuclear emergency with a release of radioactive material, considerably reduce the doses to the public in the vicinity of the nuclear installation. Although international guidelines exist, national procedures and practices may differ due to different national habits, cultural specificity, and societal needs. Different national procedures and practices may, however, in the case of a radioactive release affecting two neighbouring countries, lead to different decisions in the implementation of countermeasures. In order to better understand existing approaches and to facilitate the comparison of national practices, the NEA decided to launch a questionnaire on current practices regarding short-term countermeasures, updating a similar survey performed in 1994 and 2003, as countries' practices have since evolved and been modified. In 2012, it was decided to reevaluate the country approaches in light of the early lessons learnt from the Fukushima Daiichi NPP accident. The information collected may be used to understand the basis for decisions in various countries, and, if deemed appropriate, as a basis for international harmonisation. This may also assist member countries to explain to the public affected by an emergency why the decisions in neighbouring countries may vary. This report summarises the information given by member countries and includes nine sections to explore the different aspects, covering the following topics: member

  5. MEMS Based Acoustic Array

    Sheplak, Mark (Inventor); Nishida, Toshikaza (Inventor); Humphreys, William M. (Inventor); Arnold, David P. (Inventor)

    2006-01-01

    Embodiments of the present invention described and shown in the specification aid drawings include a combination responsive to an acoustic wave that can be utilized as a dynamic pressure sensor. In one embodiment of the present invention, the combination has a substrate having a first surface and an opposite second surface, a microphone positioned on the first surface of the substrate and having an input and a first output and a second output, wherein the input receives a biased voltage, and the microphone generates an output signal responsive to the acoustic wave between the first output and the second output. The combination further has an amplifier positioned on the first surface of the substrate and having a first input and a second input and an output, wherein the first input of the amplifier is electrically coupled to the first output of the microphone and the second input of the amplifier is electrically coupled to the second output of the microphone for receiving the output sinual from the microphone. The amplifier is spaced from the microphone with a separation smaller than 0.5 mm.

  6. Acoustics and Hearing

    Damaske, Peter

    2008-01-01

    When one listens to music at home, one would like to have an acoustic impression close to that of being in the concert hall. Until recently this meant elaborate multi-channelled sound systems with 5 or more speakers. But head-related stereophony achieves the surround-sound effect in living rooms with only two loudspeakers. By virtue of their slight directivity as well as an electronic filter the limitations previously common to two-speaker systems can be overcome and this holds for any arbitrary two-channel recording. The book also investigates the question of how a wide and diffuse sound image can arise in concert halls and shows that the quality of concert halls decisively depends on diffuse sound images arising in the onset of reverberation. For this purpose a strong onset of reverberation is modified in an anechoic chamber by electroacoustic means. Acoustics and Hearing proposes ideas concerning signal processing in the auditory system that explain the measured results and the resultant sound effects plea...

  7. Musical acoustics demonstrations

    Hoekje, P. L.

    2003-10-01

    The ASA Musical Acoustics Demonstrations website (trial version at http://www.bw.edu/~phoekje) includes sound files, video clips, program code listings, and other material for demonstrations related to musical acoustics. Many of the sound demonstrations may be experienced either as expositions, in which the phenomena are explained before they are presented, or as experiments, in which the explanation comes after listeners have had the opportunity to draw their own conclusions. Suggestions are provided for apparatus construction and classroom experiments, as well as for building simple musical instruments. Software is recommended if it is available free and compatible with multiple personal computer operating systems. For example, Audacity (http://audacity.sourceforce.net) is a sound file editor and analyzer that can be used to visually represent sounds and manipulate them. Source files are included for the synthesized sound examples, which were created in Csound (http://csounds.com), so that interested users may create their own variations. Source code is also included for visual demonstrations created in Visual Python and Python (http://www.python.org), an efficient, high level programming language. Suggestions, criticisms, and contributions are always welcome! [Work supported by ASA and Baldwin-Wallace College.

  8. Time-reversal acoustics

    Fink, Mathias [Laboratoire Ondes et Acoustique, Ecole Superieure de Physique et de Chimie Industrielle de la Ville de Paris, Universite Denis Diderot, UMR CNRS 7587, 10 Rue Vauquelin, 75005 Paris (France)], E-mail: mathias.fink@espci.fr

    2008-10-15

    Time-reversal mirrors (TRMs) refocus an incident acoustic field to the position of the original source regardless of the complexity of the propagation medium. TRM's have now been implemented in a variety of physical scenarios from MHz ultrasonics with order centimeter aperture size to hundreds/thousands of Hz in ocean acoustics with order hundred meter aperture size. Common to this broad range of scales is a remarkable robustness exemplified by observations at all scales that the more complex the medium between the probe source and the TRM, the sharper the focus. The relation between the medium complexity and the size of the focal spot is studied in this paper. It is certainly the most exciting property of TRM compared to standard focusing devices. A TRM acts as an antenna that uses complex environments to appears wider than it is, resulting for a broadband pulse in a refocusing quality that does not depend of the TRM aperture. In this paper, we investigate the time-reversal approach in various media of increasing complexity and we discuss the link existing between time-reversal approach and local helioseismology where Green's functions can be extracted from diffusive noise.

  9. Acoustic Absorption in Porous Materials

    Kuczmarski, Maria A.; Johnston, James C.

    2011-01-01

    An understanding of both the areas of materials science and acoustics is necessary to successfully develop materials for acoustic absorption applications. This paper presents the basic knowledge and approaches for determining the acoustic performance of porous materials in a manner that will help materials researchers new to this area gain the understanding and skills necessary to make meaningful contributions to this field of study. Beginning with the basics and making as few assumptions as possible, this paper reviews relevant topics in the acoustic performance of porous materials, which are often used to make acoustic bulk absorbers, moving from the physics of sound wave interactions with porous materials to measurement techniques for flow resistivity, characteristic impedance, and wavenumber.

  10. Acoustic monitoring method and device

    The present invention provides a method of eliminating resonance noises upon acoustically monitoring the operation state of power plants and plant equipments whether they are normal or not, to improve sensitivity for detecting abnormalities. Namely, a microphone detects acoustic signals including leaking sounds and converts them into electric signals. An amplifier amplifies the electric signals to an appropriate level. A noise eliminating section eliminates resonance noises other than the leaking sounds. An abnormality judging section judges presence of abnormality based on the level of the acoustic signals of the leaking sounds. With such a constitution, a plurality of resonance noises generated also during normal plant operation are automatically eliminated. Since resonance noises as a factor of lowering the sensitivity for abnormal sound detection are not included in the acoustic signals, the sensitivity for the abnormal sound detection is improved. Accordingly, the performance of the acoustic monitoring device is improved. (I.S.)