Rattling Nucleons: New Developments in Active Interrogation of Special Nuclear Material
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robert C. Runkle; David L. Chichester; Scott J. Thompson
2012-01-01
Active interrogation is a vigorous area of research and development due to its promise of offering detection and characterization capabilities of special nuclear material in environments where passive detection fails. The primary value added by active methods is the capability to penetrate shielding - special nuclear material itself, incidental materials, or intentional shielding - and advocates hope that active interrogation will provide a solution to the problem of detecting shielded uranium, which is at present the greatest obstacle to interdiction efforts. The technique also provides a unique benefit for quantifying nuclear material in high background-radiation environments, an area important formore » nuclear material safeguards and material accountancy. Progress has been made in the field of active interrogation on several fronts, most notably in the arenas of source development, systems integration, and the integration and exploitation of multiple fission and non-fission signatures. But penetration of interrogating radiation often comes at a cost, not only in terms of finance and dose but also in terms of induced backgrounds, system complexity, and extended measurement times (including set up and acquisition). These costs make the calculus for deciding to implement active interrogation more subtle than may be apparent. The purpose of this review is thus to examine existing interrogation methods, compare and contrast their attributes and limitations, and identify missions where active interrogation may hold the most promise.« less
Rattling nucleons: New developments in active interrogation of special nuclear material
NASA Astrophysics Data System (ADS)
Runkle, Robert C.; Chichester, David L.; Thompson, Scott J.
2012-01-01
Active interrogation is a vigorous area of research and development due to its promise of offering detection and characterization capabilities of special nuclear material in environments where passive detection fails. The primary value added by active methods is the capability to penetrate shielding—special nuclear material itself, incidental materials, or intentional shielding—and advocates hope that active interrogation will provide a solution to the problem of detecting shielded uranium, which is at present the greatest obstacle to interdiction efforts. The technique also provides a unique benefit for quantifying nuclear material in high background-radiation environments, an area important for nuclear material safeguards and material accountancy. Progress has been made in the field of active interrogation on several fronts, most notably in the arenas of source development, systems integration, and the integration and exploitation of multiple fission and non-fission signatures. But penetration of interrogating radiation often comes at a cost, not only in terms of finance and dose but also in terms of induced backgrounds, system complexity, and extended measurement times (including set up and acquisition). These costs make the calculus for deciding to implement active interrogation more subtle than may be apparent. The purpose of this review is thus to examine existing interrogation methods, compare and contrast their attributes and limitations, and identify missions where active interrogation may hold the most promise.
Active-Interrogation Measurements of Fast Neutrons from Induced Fission in Low-Enriched Uranium
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. L. Dolan; M. J. Marcath; M. Flaska
2014-02-01
A detection system was designed with MCNPX-PoliMi to measure induced-fission neutrons from U-235 and U-238 using active interrogation. Measurements were then performed with this system at the Joint Research Centre (JRC) in Ispra, Italy on low-enriched uranium samples. Liquid scintillators measured induced fission neutron to characterize the samples in terms of their uranium mass and enrichment. Results are presented to investigate and support the use of organic liquid scintillators with active interrogation techniques to characterize uranium containing materials.
NASA Astrophysics Data System (ADS)
Takahashi, Y.; Misawa, T.; Yagi, T.; Pyeon, C. H.; Kimura, M.; Masuda, K.; Ohgaki, H.
2015-10-01
The detection of special nuclear materials (SNM) is an important issue for nuclear security. The interrogation systems used in a sea port and an airport are developed in the world. The active neutron-based interrogation system is the one of the candidates. We are developing the active neutron-based interrogation system with a D-D fusion neutron source for the nuclear security application. The D-D neutron source is a compact discharge-type fusion neutron source called IEC (Inertial-Electrostatic Confinement fusion) device which provides 2.45 MeV neutrons. The nuclear materials emit the highenergy neutrons by fission reaction. High-energy neutrons with energies over 2.45 MeV amount to 30% of all the fission neutrons. By using the D-D neutron source, the detection of SNMs is considered to be possible with the attention of fast neutrons if there is over 2.45 MeV. Ideally, neutrons at En>2.45 MeV do not exist if there is no nuclear materials. The detection of fission neutrons over 2.45 MeV are hopeful prospect for the detection of SNM with a high S/N ratio. In the future, the experiments combined with nuclear materials and a D-D neutron source will be conducted. Furthermore, the interrogation system will be numerically investigated by using nuclear materials, a D-D neutron source, and a steel container.
Characterization of a FBG sensor interrogation system based on a mode-locked laser scheme.
Madrigal, Javier; Fraile-Peláez, Francisco Javier; Zheng, Di; Barrera, David; Sales, Salvador
2017-10-02
This paper is focused on the characterization of a fiber Bragg grating (FBG) sensor interrogation system based on a fiber ring laser with a semiconductor optical amplifier as the gain medium, and an in-loop electro-optical modulator. This system operates as a switchable active (pulsed) mode-locked laser. The operation principle of the system is explained theoretically and validated experimentally. The ability of the system to interrogate an array of different FBGs in wavelength and spatial domain is demonstrated. Simultaneously, the influence of several important parameters on the performance of the interrogation technique has been investigated. Specifically, the effects of the bandwidth and the reflectivity of the FBGs, the SOA gain, and the depth of the intensity modulation have been addressed.
Impact of fiber ring laser configuration on detection capabilities in FBG based sensor systems
NASA Astrophysics Data System (ADS)
Osuch, Tomasz; Kossek, Tomasz; Markowski, Konrad
2014-11-01
In this paper fiber ring lasers (FRL) as interrogation units for distributed fiber Bragg grating (FBG) based sensor networks are studied. In particular, two configurations of the fiber laser with erbium-doped fiber amplifier (EDFA) and semiconductor optical amplifier (SOA) as gain medium were analyzed. In the case of EDFA-based fiber interrogation systems, CW as well as active-mode locking operation were taken into account. The influence of spectral overlapping of FBGs spectra on detection capabilities of examined FRLs are presented. Experimental results show that the SOA-based fiber laser interrogation unit can operate as a multi-parametric sensing system. In turn, using an actively mode-locked fiber ring laser with an EDFA, an electronically switchable FBG based sensing system can be realized.
Detectors for Active Interrogation Applications
NASA Astrophysics Data System (ADS)
Clarke, S. D.; Hamel, M. C.; Bourne, M. M.; Pozzi, S. A.
Active interrogation creates an environment that is particularly challenging from a radiation-detection standpoint: the elevated background levels from the source can mask the desired signatures from the SNM. Neutron based interrogation experiments have shown that nanosecond-level timing is required to discriminate induced-fission neutrons from the scattered source neutrons. Previous experiments using high-energy bremsstrahlung X-rays have demonstrated the ability to induce and detect prompt photofission neutrons from single target materials; however, a real-world application would require spectroscopic capability to discern between photofission neutrons emitted by SNM and neutrons emitted by other reactions in non-SNM. Using digital pulse-shape discrimination, organic liquid scintillators are capable of reliably detecting neutrons in an intense gamma-ray field. Photon misclassification rates as low as 1 in 106 have been achieved, which is approaching the level of gaseous neutron detectors such as 3He without the need for neutron moderation. These scintillators also possess nanosecond-timing resolution, making them candidates for both neutron-and photon-driven active interrogation systems. We have applied an array of liquid and NaI(Tl) scintillators to successfully image 13.7 kg of HEU interrogated by a DT neutron generator; the system was in the direct presence of the accelerator during the experiment.
Hybrid Monte Carlo/Deterministic Methods for Accelerating Active Interrogation Modeling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peplow, Douglas E.; Miller, Thomas Martin; Patton, Bruce W
2013-01-01
The potential for smuggling special nuclear material (SNM) into the United States is a major concern to homeland security, so federal agencies are investigating a variety of preventive measures, including detection and interdiction of SNM during transport. One approach for SNM detection, called active interrogation, uses a radiation source, such as a beam of neutrons or photons, to scan cargo containers and detect the products of induced fissions. In realistic cargo transport scenarios, the process of inducing and detecting fissions in SNM is difficult due to the presence of various and potentially thick materials between the radiation source and themore » SNM, and the practical limitations on radiation source strength and detection capabilities. Therefore, computer simulations are being used, along with experimental measurements, in efforts to design effective active interrogation detection systems. The computer simulations mostly consist of simulating radiation transport from the source to the detector region(s). Although the Monte Carlo method is predominantly used for these simulations, difficulties persist related to calculating statistically meaningful detector responses in practical computing times, thereby limiting their usefulness for design and evaluation of practical active interrogation systems. In previous work, the benefits of hybrid methods that use the results of approximate deterministic transport calculations to accelerate high-fidelity Monte Carlo simulations have been demonstrated for source-detector type problems. In this work, the hybrid methods are applied and evaluated for three example active interrogation problems. Additionally, a new approach is presented that uses multiple goal-based importance functions depending on a particle s relevance to the ultimate goal of the simulation. Results from the examples demonstrate that the application of hybrid methods to active interrogation problems dramatically increases their calculational efficiency.« less
Innocence and resisting confession during interrogation: effects on physiologic activity.
Guyll, Max; Madon, Stephanie; Yang, Yueran; Lannin, Daniel G; Scherr, Kyle; Greathouse, Sarah
2013-10-01
Innocent suspects may not adequately protect themselves during interrogation because they fail to fully appreciate the danger of the situation. This experiment tested whether innocent suspects experience less stress during interrogation than guilty suspects, and whether refusing to confess expends physiologic resources. After experimentally manipulating innocence and guilt, 132 participants were accused and interrogated for misconduct, and then pressured to confess. Systolic and diastolic blood pressure (SBP, DBP), heart rate (HR), respiratory sinus arrhythmia (RSA), and preejection period (PEP) responses quantified stress reactions. As hypothesized, the innocent evidenced smaller stress responses to interrogation for SBP, DBP, HR, and RSA than did the guilty. Furthermore, innocents who refused to confess exhibited greater sympathetic nervous system activation, as evidenced by shorter PEPs, than did innocent or guilty confessors. These findings suggest that innocent suspects underestimate the threat of interrogation and that resisting pressures to confess can diminish suspects' physiologic resources and lead to false confessions. PsycINFO Database Record (c) 2013 APA, all rights reserved
Detectors for Active Interrogation Applications
Clarke, S. D.; Hamel, M. C.; Bourne, M. M.; ...
2017-10-26
Active interrogation creates an environment that is particularly challenging from a radiation-detection standpoint: the elevated background levels from the source can mask the desired signatures from the SNM. Neutron based interrogation experiments have shown that nanosecond-level timing is required to discriminate induced-fission neutrons from the scattered source neutrons. Previous experiments using high-energy bremsstrahlung X-rays have demonstrated the ability to induce and detect prompt photofission neutrons from single target materials; however, a real-world application would require spectroscopic capability to discern between photofission neutrons emitted by SNM and neutrons emitted by other reactions in non-SNM. Using digital pulseshape discrimination, organic liquid scintillatorsmore » are capable of reliably detecting neutrons in an intense gamma-ray field. Photon misclassification rates as low as 1 in 10 6 have been achieved, which is approaching the level of gaseous neutron detectors such as 3He without the need for neutron moderation. These scintillators also possess nanosecond-timing resolution, making them candidates for both neutron-and photon-driven active interrogation systems. Lastly, we have applied an array of liquid and NaI(Tl) scintillators to successfully image 13.7 kg of HEU interrogated by a DT neutron generator; the system was in the direct presence of the accelerator during the experiment.« less
Active damage interrogation system for structural health monitoring
NASA Astrophysics Data System (ADS)
Lichtenwalner, Peter F.; Dunne, James P.; Becker, Ronald S.; Baumann, Erwin W.
1997-05-01
An integrated and automated smart structures approach for in situ damage assessment has been implemented and evaluated in a laboratory environment for health monitoring of a realistic aerospace structural component. This approach, called Active Damage Interrogation (ADI), utilizes an array of piezoelectric transducers attached to or embedded within the structure for both actuation and sensing. The ADI system, which is model independent, actively interrogates the structure through broadband excitation of multiple actuators across the desired frequency range. Statistical analysis of the changes in transfer functions between actuator/sensor pairs is used to detect, localize, and assess the severity of damage in the structure. This paper presents the overall concept of the ADI system and provides experimental results of damage assessment studies conducted for a composite structural component of the MD-900 Explorer helicopter rotor system. The potential advantages of this approach include simplicity (no need for a model), sensitivity, and low cost implementation. The results obtained thus far indicate considerably promise for integrated structural health monitoring of aerospace vehicles, leading to the practice of condition-based maintenance and consequent reduction in life cycle costs.
Active-Interrogation Measurements of Induced-Fission Neutrons from Low-Enriched Uranium
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. L. Dolan; M. J. Marcath; M. Flaska
2012-07-01
Protection and control of nuclear fuels is paramount for nuclear security and safeguards; therefore, it is important to develop fast and robust controlling mechanisms to ensure the safety of nuclear fuels. Through both passive- and active-interrogation methods we can use fast-neutron detection to perform real-time measurements of fission neutrons for process monitoring. Active interrogation allows us to use different ranges of incident neutron energy to probe for different isotopes of uranium. With fast-neutron detectors, such as organic liquid scintillation detectors, we can detect the induced-fission neutrons and photons and work towards quantifying a sample’s mass and enrichment. Using MCNPX-PoliMi, amore » system was designed to measure induced-fission neutrons from U-235 and U-238. Measurements were then performed in the summer of 2010 at the Joint Research Centre in Ispra, Italy. Fissions were induced with an associated particle D-T generator and an isotopic Am-Li source. The fission neutrons, as well as neutrons from (n, 2n) and (n, 3n) reactions, were measured with five 5” by 5” EJ-309 organic liquid scintillators. The D-T neutron generator was available as part of a measurement campaign in place by Padova University. The measurement and data-acquisition systems were developed at the University of Michigan utilizing a CAEN V1720 digitizer and pulse-shape discrimination algorithms to differentiate neutron and photon detections. Low-enriched uranium samples of varying mass and enrichment were interrogated. Acquired time-of-flight curves and cross-correlation curves are currently analyzed to draw relationships between detected neutrons and sample mass and enrichment. In the full paper, the promise of active-interrogation measurements and fast-neutron detection will be assessed through the example of this proof-of-concept measurement campaign. Additionally, MCNPX-PoliMi simulation results will be compared to the measured data to validate the MCNPX-PoliMi code when used for active-interrogation simulations.« less
The development of enabling technologies for producing active interrogation beams.
Kwan, Thomas J T; Morgado, Richard E; Wang, Tai-Sen F; Vodolaga, B; Terekhin, V; Onischenko, L M; Vorozhtsov, S B; Samsonov, E V; Vorozhtsov, A S; Alenitsky, Yu G; Perpelkin, E E; Glazov, A A; Novikov, D L; Parkhomchuk, V; Reva, V; Vostrikov, V; Mashinin, V A; Fedotov, S N; Minayev, S A
2010-10-01
A U.S./Russian collaboration of accelerator scientists was directed to the development of high averaged-current (∼1 mA) and high-quality (emittance ∼15 πmm mrad; energy spread ∼0.1%) 1.75 MeV proton beams to produce active interrogation beams that could be applied to counterterrorism. Several accelerator technologies were investigated. These included an electrostatic tandem accelerator of novel design, a compact cyclotron, and a storage ring with energy compensation and electron cooling. Production targets capable of withstanding the beam power levels were designed, fabricated, and tested. The cyclotron/storage-ring system was theoretically studied and computationally designed, and the electrostatic vacuum tandem accelerator at BINP was demonstrated for its potential in active interrogation of explosives and special nuclear materials.
Active interrogation using low-energy nuclear reactions
NASA Astrophysics Data System (ADS)
Antolak, Arlyn; Doyle, Barney; Leung, Ka-Ngo; Morse, Daniel; Provencio, Paula
2005-09-01
High-energy photons and neutrons can be used to interrogate for heavily shielded fissile materials inside sealed cargo containers by detecting their prompt and/or delayed fission signatures. The FIND (Fissmat Inspection for Nuclear Detection) active interrogation system is based on a dual neutron+gamma source that uses low-energy (< 500 keV) proton- or deuteron-induced nuclear reactions to produce high intensities of mono-energetic gamma rays and/or neutrons. The source can be operated in either pulsed (e.g., to detect delayed photofission neutrons and gammas) or continuous (e.g., detecting prompt fission signatures) modes. For the gamma-rays, the source target can be segmented to incorporate different (p,γ) isotopes for producing gamma-rays at selective energies, thereby improving the probability of detection. The design parameters for the FIND system are discussed and preliminary accelerator-based measurements of gamma and neutron yields, background levels, and fission signals for several target materials under consideration are presented.
Nimbus 4/IRLS Balloon Interrogation Package (BIP)
NASA Technical Reports Server (NTRS)
1971-01-01
The balloon interrogation package (BIP), an integral part of the overall interrogation, recording, and location subsystems (IRLS) for the Nimbus 4 program, is described. The BIP is a self-contained, integrated transponder designed to be carried aloft by a constant altitude, superpressure balloon to an altitude of 67,000 or 78,000 feet. After launch the BIP senses high-altitude balloon overpressure and temperature, and upon receipt of an interrogated command from the IRLS aboard the Nimbus 4 satellite, the BIP enodes the data on a real-time basis into a pulse-code modulation (PCM) format and transmits this data to the satellite. A summary of the program activity to produce 30 BIP systems and to support balloon launches from Ascension Island is presented.
NASA Astrophysics Data System (ADS)
Grogan, Brandon R.; Henkel, James J.; Johnson, Jeffrey O.; Mihalczo, John T.; Miller, Thomas M.; Patton, Bruce W.
2013-12-01
The detonation of a terrorist nuclear weapon in the United States would result in the massive loss of life and grave economic damage. Even if a device was not detonated, its known or suspected presence aboard a cargo container ship in a U.S. port would have major economic and political consequences. One possible means to prevent this threat would be to board a ship at sea and search for the device before it reaches port. The scenario considered here involves a small Coast Guard team with strong intelligence boarding a container ship to search for a nuclear device. Using active interrogation, the team would nonintrusively search a block of shipping containers to locate the fissile material. Potential interrogation source and detector technologies for the team are discussed. The methodology of the scan is presented along with a technique for calculating the required interrogation source strength using computer simulations. MCNPX was used to construct a computer model of a container ship, and several search scenarios were simulated. The results of the simulations are presented in terms of the source strength required for each interrogation scenario. Validation measurements were performed in order to scale these simulation results to expected performance. Interrogations through the short (2.4 m) axis of a standardized shipping container appear to be feasible given the entire range of container loadings tested. Interrogations through several containers at once or a single container through its long (12.2 m) axis do not appear to be viable with a portable interrogation system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clarke, S. D.; Hamel, M. C.; Bourne, M. M.
Active interrogation creates an environment that is particularly challenging from a radiation-detection standpoint: the elevated background levels from the source can mask the desired signatures from the SNM. Neutron based interrogation experiments have shown that nanosecond-level timing is required to discriminate induced-fission neutrons from the scattered source neutrons. Previous experiments using high-energy bremsstrahlung X-rays have demonstrated the ability to induce and detect prompt photofission neutrons from single target materials; however, a real-world application would require spectroscopic capability to discern between photofission neutrons emitted by SNM and neutrons emitted by other reactions in non-SNM. Using digital pulseshape discrimination, organic liquid scintillatorsmore » are capable of reliably detecting neutrons in an intense gamma-ray field. Photon misclassification rates as low as 1 in 10 6 have been achieved, which is approaching the level of gaseous neutron detectors such as 3He without the need for neutron moderation. These scintillators also possess nanosecond-timing resolution, making them candidates for both neutron-and photon-driven active interrogation systems. Lastly, we have applied an array of liquid and NaI(Tl) scintillators to successfully image 13.7 kg of HEU interrogated by a DT neutron generator; the system was in the direct presence of the accelerator during the experiment.« less
Monolithic integrated optic fiber Bragg grating sensor interrogator
NASA Astrophysics Data System (ADS)
Mendoza, Edgar A.; Esterkin, Yan; Kempen, Cornelia; Sun, Songjian
2010-04-01
Fiber Bragg gratings (FBGs) are a mature sensing technology that has gained rapid acceptance in civil, aerospace, chemical and petrochemical, medicine, aviation and automotive industries. Fiber Bragg grating sensors can be use for a variety of measurements including strain, stress, vibration, acoustics, acceleration, pressure, temperature, moisture, and corrosion distributed at multiple locations within the structure using a single fiber element. The most prominent advantages of FBGs are: small size and light weight, multiple FBG transducers on a single fiber, and immunity to radio frequency interference. A major disadvantage of FBG technology is that conventional state-of-the-art fiber Bragg grating interrogation systems are typically bulky, heavy, and costly bench top instruments that are assembled from off-the-shelf fiber optic and optical components integrated with a signal electronics board into an instrument console. Based on the need for a compact FBG interrogation system, this paper describes recent progress towards the development of a miniature fiber Bragg grating sensor interrogator (FBG-TransceiverTM) system based on multi-channel monolithic integrated optic sensor microchip technology. The integrated optic microchip technology enables the monolithic integration of all of the functionalities, both passive and active, of conventional bench top FBG sensor interrogators systems, packaged in a miniaturized, low power operation, 2-cm x 5-cm small form factor (SFF) package suitable for the long-term structural health monitoring in applications where size, weight, and power are critical for operation.
NASA Astrophysics Data System (ADS)
Grimes, T. F.; Hagen, A. R.; Archambault, B. C.; Taleyarkhan, R. P.
2018-03-01
This paper describes the development of a SNM detection system for interrogating 1m3 cargos via the combination of a D-D neutron interrogation source (with and without reflectors) and tensioned metastable fluid detectors (TMFDs). TMFDs have been previously shown (Taleyarkhan et al., 2008; Grimes et al., 2015; Grimes and Taleyarkhan, 2016; Archambault et al., 2017; Hagen et al., 2016) to be capable of using Threshold Energy Neutron Analysis (TENA) techniques to reject the ∼2.45 MeV D-D interrogating neutrons while still remaining sensitive to >2.45 MeV neutrons resulting from fission in the target (HEU) material. In order to enhance the performance, a paraffin reflector was included around the accelerator head. This reflector was used to direct neutrons into the package to increase the fission signal, lower the energy of the interrogating neutrons to increase the fission cross-section with HEU, and, also to direct interrogating neutrons away from the detectors in order to enhance the required discrimination between interrogating and fission neutrons. Experiments performed with a 239 Pu-Be neutron source and MnO2 indicated that impressive performance gains could be made by placing a parabolic paraffin moderator between the interrogation source and an air-filled cargo container with HEU placed at the center. However, experiments with other cargo fillers (as specified in the well-known ANSI N42.41-2007 report), and with HEU placed in locations other than the center of the package indicated that other reflector geometries might be superior due to over-"focusing" and the increased solid angle effects due to the accommodation of the moderator geometry. The best performance for the worst case of source location and box fill was obtained by placing the reflector only behind the D-D neutron source rather than in front of it. Finally, it was shown that there could be significant gains in the ability to detect concealed SNM by operating the system in multiple geometric configurations. Worst case scenarios were created by filling the box with hydrogenous material and placing the HEU as far away as possible from the neutron source. The performance of the system in the worst-case scenarios were greatly improved by exchanging the location of the accelerator and the opposite TMFD panel half way through interrogation. Using this operation, scenarios with positions of the concealed SNM that were once the most challenging to successfully detect became readily detectable.
Personnel Dose Assessment during Active Interrogation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, Thomas Martin; Akkurt, Hatice; Patton, Bruce W
A leading candidate in the detection of special nuclear material (SNM) is active interrogation (AI). Unlike passive interrogation, AI uses a source to enhance or create a detectable signal from SNM (usually fission), particularly in shielded scenarios or scenarios where the SNM has a low activity. The use of AI thus makes the detection of SNM easier or, in some scenarios, even enables previously impossible detection. During the development of AI sources, significant effort is put into determining the source strength required to detect SNM in specific scenarios. Usually during this process, but not always, an evaluation of personnel dosemore » is also completed. In this instance personnel dose could involve any of the following: (1) personnel performing the AI; (2) unknown stowaways who are inside the object being interrogated; or (3) in clandestine interrogations, personnel who are known to be inside the object being interrogated but are unaware of the interrogation. In most instances, dose to anyone found smuggling SNM will be a secondary issue. However, for the organizations performing the AI, legal if not moral considerations should make dose to the personnel performing the AI, unknown stowaways, or innocent bystanders in clandestine interrogations a serious concern.« less
Detecting terrorist nuclear weapons at sea: The 10th door problem
DOE Office of Scientific and Technical Information (OSTI.GOV)
Slaughter, D R
2008-09-15
While screening commercial cargo containers for the possible presence of WMD is important and necessary smugglers have successfully exploited the many other vehicles transporting cargo into the US including medium and small vessels at sea. These vessels provide a venue that is currently not screened and widely used. Physics limits that make screening of large vessels prohibitive impractical do not prohibit effective screening of the smaller vessels. While passive radiation detection is probably ineffective at sea active interrogation may provide a successful approach. The physics limits of active interrogation of ships at sea from standoff platforms are discussed. Autonomous platformsmore » that could carry interrogation systems at sea, both airborne and submersible, are summarized and their utilization discussed. An R&D program to investigate the limits of this approach to screening ships at sea is indicated and limitations estimated.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joshi, Jay Prakash
The effective application of international safeguards to research reactors requires verification of spent fuel as well as fresh fuel. To accomplish this goal various nondestructive and destructive assay techniques have been developed in the US and around the world. The Advanced Experimental Fuel Counter (AEFC) is a nondestructive assay (NDA) system developed at Los Alamos National Laboratory (LANL) combining both neutron and gamma measurement capabilities. Since spent fuel assemblies are stored in water, the system was designed to be watertight to facilitate underwater measurements by inspectors. The AEFC is comprised of six 3He detectors as well as a shielded andmore » collimated ion chamber. The 3He detectors are used for active and passive neutron coincidence counting while the ion chamber is used for gross gamma counting. Active coincidence measurement data is used to measure residual fissile mass, whereas the passive coincidence measurement data along with passive gamma measurement can provide information about burnup, cooling time, and initial enrichment. In the past, most of the active interrogation systems along with the AEFC used an AmLi neutron interrogation source. Owing to the difficulty in obtaining an AmLi source, a 252Cf spontaneous fission (SF) source was used during a 2014 field trail in Uzbekistan as an alternative. In this study, experiments were performed to calibrate the AEFC instrument and compare use of the 252Cf spontaneous fission source and the AmLi (α,n) neutron emission source. The 252Cf source spontaneously emits bursts of time-correlated prompt fission neutrons that thermalize in the water and induce fission in the fuel assembly. The induced fission (IF) neutrons are also time correlated resulting in more correlated neutron detections inside the 3He detector, which helps reduce the statistical errors in doubles when using the 252Cf interrogation source instead of the AmLi source. In this work, two MTR fuel assemblies varying both in size and number of fuel plates were measured using 252Cf and AmLi active interrogation sources. This paper analyzes time correlated induced fission (TCIF) from fresh MTR fuel assemblies due to 252Cf and AmLi active interrogation sources.« less
Zhang, Yunlong; Li, Ruoming; Shi, Yuechun; Zhang, Jintao; Chen, Xiangfei; Liu, Shengchun
2015-06-01
A novel fiber Bragg grating aided fiber loop ringdown (FLRD) sensor array and the wavelength-time multiplexing based interrogation technique for the FLRD sensors array are proposed. The interrogation frequency of the system is formulated and the interrelationships among the parameters of the system are analyzed. To validate the performance of the proposed system, a five elements array is experimentally demonstrated, and the system shows the capability of real time monitoring every FLRD element with interrogation frequency of 125.5 Hz.
NASA Astrophysics Data System (ADS)
Griggs, Steven P.; Mark, Martin B.; Feldman, Barry J.
2004-07-01
The goal of the DARPA Dynamic Optical Tags (DOTs) program is to develop a small, robust, persistent, 2-way tagging, tracking and locating device that also supports communications at data rates greater than 100 kbps and can be interrogated at significant range. These tags will allow for two-way data exchange and tagging operations in friendly and denied areas. The DOTs will be passive and non-RF. To accomplish this, the DOTs program will develop small, thin, retro-reflecting modulators. The tags will operate for long periods of time (greater than two months) in real-world environmental conditions (-40° to +70° C) and allow for a wide interrogation angle (+/-60°). The tags will be passive (in the sleep mode) for most of the time and only become active when interrogated by a laser with the correct code. Once correctly interrogated, the tags will begin to modulate and retro-reflect the incoming beam. The program will also develop two tag specific transceiver systems that are eye-safe, employ automated scanning algorithms, and are capable of short search and interrogate times.
Remote file inquiry (RFI) system
NASA Technical Reports Server (NTRS)
1975-01-01
System interrogates and maintains user-definable data files from remote terminals, using English-like, free-form query language easily learned by persons not proficient in computer programming. System operates in asynchronous mode, allowing any number of inquiries within limitation of available core to be active concurrently.
Roberts, Jeffery; Aines, Roger D; Duoss, Eric B; Spadaccini, Christopher M
2014-11-04
An apparatus, method, and system of reservoir interrogation. A tracer is encapsulating in a receptacle. The receptacle containing the tracer is injected into the reservoir. The tracer is analyzed for reservoir interrogation.
NASA Technical Reports Server (NTRS)
Glover, Richard D.
1987-01-01
A pipelined, multiprocessor, general-purpose ground support equipment for digital flight systems has been developed and placed in service at the NASA Ames Research Center's Dryden Flight Research Facility. The design is an outgrowth of the earlier aircraft interrogation and display system (AIDS) used in support of several research projects to provide engineering-units display of internal control system parameters during development and qualification testing activities. The new system, incorporating multiple 16-bit processors, is called extended AIDS (XAIDS) and is now supporting the X-29A forward-swept-wing aircraft project. This report describes the design and mechanization of XAIDS and shows the steps whereby a typical user may take advantage of its high throughput and flexible features.
Active Interrogation of Sensitive Nuclear Material Using Laser Driven Neutron Beams
DOE Office of Scientific and Technical Information (OSTI.GOV)
Favalli, Andrea; Roth, Markus
2015-05-01
An investigation of the viability of a laser-driven neutron source for active interrogation is reported. The need is for a fast, movable, operationally safe neutron source which is energy tunable and has high-intensity, directional neutron production. Reasons for the choice of neutrons and lasers are set forth. Results from the interrogation of an enriched U sample are shown.
Multi-level RF identification system
Steele, Kerry D.; Anderson, Gordon A.; Gilbert, Ronald W.
2004-07-20
A radio frequency identification system having a radio frequency transceiver for generating a continuous wave RF interrogation signal that impinges upon an RF identification tag. An oscillation circuit in the RF identification tag modulates the interrogation signal with a subcarrier of a predetermined frequency and modulates the frequency-modulated signal back to the transmitting interrogator. The interrogator recovers and analyzes the subcarrier signal and determines its frequency. The interrogator generates an output indicative of the frequency of the subcarrier frequency, thereby identifying the responding RFID tag as one of a "class" of RFID tags configured to respond with a subcarrier signal of a predetermined frequency.
Interrogations, confessions, and adolescent offenders' perceptions of the legal system.
Arndorfer, Andrea; Malloy, Lindsay C; Cauffman, Elizabeth
2015-10-01
The potential consequences of interrogations and false confessions have been discussed primarily in terms of the risk for wrongful conviction, especially among adolescents and other vulnerable populations. However, it is possible that such experiences influence adolescents' perceptions of the legal system more generally. In the present study, we examined whether incarcerated male juvenile offenders' (n = 193) perceptions of police and the courts were related to their confession and interrogation experiences. High-pressure interrogation experiences and self-reported false confessions to police were associated with more negative perceptions of police. However, self-reported true confessions were not significantly associated with youths' perceptions of the police. Neither interrogation nor confession experiences (true or false) were related to youths' perceptions of the courts. Results provide additional support for policy reform of interrogation practices with young suspects. A more developmentally appropriate approach to criminal interrogations with youth may simultaneously improve police-youth relations and protect vulnerable suspects in the interrogation room. (c) 2015 APA, all rights reserved).
DOE Office of Scientific and Technical Information (OSTI.GOV)
E.H. Seabury; D.L. Chichester; C.J. Wharton
2008-08-01
Prompt Gamma Neutron Activation Analysis (PGNAA) systems employ neutrons as a probe to interrogate items, e.g. chemical warfare materiel-filled munitions. The choice of a neutron source in field-portable systems is determined by its ability to excite nuclei of interest, operational concerns such as radiological safety and ease-of-use, and cost. Idaho National Laboratory’s PINS Chemical Assay System has traditionally used a Cf-252 isotopic neutron source, but recently a Deuterium-Tritium (DT) Electronic Neutron Generator (ENG) has been tested as an alternate neutron source. This paper presents the results of using both of these neutron sources to interrogate chemical warfare materiel (CWM) andmore » high explosive (HE) filled munitions.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seabury, E. H.; Chichester, D. L.; Wharton, C. J.
2009-03-10
Prompt Gamma Neutron Activation Analysis (PGNAA) systems employ neutrons as a probe to interrogate items, e.g. chemical warfare materiel-filled munitions. The choice of a neutron source in field-portable systems is determined by its ability to excite nuclei of interest, operational concerns such as radiological safety and ease-of-use, and cost. Idaho National Laboratory's PINS Chemical Assay System has traditionally used a {sup 252}Cf isotopic neutron source, but recently a deuterium-tritium (DT) electronic neutron generator (ENG) has been tested as an alternate neutron source. This paper presents the results of using both of these neutron sources to interrogate chemical warfare materiel (CWM)more » and high explosive (HE) filled munitions.« less
A MHz speed wavelength sweeping for ultra-high speed FBG interrogation
NASA Astrophysics Data System (ADS)
Kim, Gyeong Hun; Lee, Hwi Don; Eom, Tae Joong; Jeong, Myung Yung; Kim, Chang-Seok
2015-09-01
We demonstrated a MHz speed wavelength-swept fiber laser based on the active mode locking (AML) technique and applied to interrogation system of an array of fiber Bragg grating (FBG) sensors. MHz speed wavelength sweeping of wavelength-swept fiber laser can be obtained by programmable frequency modulation of the semiconductor optical amplifier (SOA) without any wavelength tunable filter. Both static and dynamic strain measurement of FBG sensors were successfully characterized with high linearity of an R-square value of 0.9999 at sweeping speed of 50 kHz.
Active Interrogation for Spent Fuel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swinhoe, Martyn Thomas; Dougan, Arden
2015-11-05
The DDA instrument for nuclear safeguards is a fast, non-destructive assay, active neutron interrogation technique using an external 14 MeV DT neutron generator for characterization and verification of spent nuclear fuel assemblies.
Nanowire humidity optical sensor system based on fast Fourier transform technique
NASA Astrophysics Data System (ADS)
Rota-Rodrigo, S.; Pérez-Herrera, R.; Lopez-Aldaba, A.; López Bautista, M. C.; Esteban, O.; López-Amo, M.
2015-09-01
In this paper, a new sensor system for relative humidity measurements based on its interaction with the evanescent field of a nanowire is presented. The interrogation of the sensing head is carried out by monitoring the fast Fourier transform phase variations of one of the nanowire interference frequencies. This method is independent of the signal amplitude and also avoids the necessity of tracking the wavelength evolution in the spectrum, which can be a handicap when there are multiple interference frequency components with different sensitivities. The sensor is operated within a wide humidity range (20%-70% relative humidity) with a maximum sensitivity achieved of 0.14rad/% relative humidity. Finally, due to the system uses an optical interrogator as unique active element, the system presents a cost-effective feature.
Development and application of a hybrid transport methodology for active interrogation systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Royston, K.; Walters, W.; Haghighat, A.
A hybrid Monte Carlo and deterministic methodology has been developed for application to active interrogation systems. The methodology consists of four steps: i) neutron flux distribution due to neutron source transport and subcritical multiplication; ii) generation of gamma source distribution from (n, 7) interactions; iii) determination of gamma current at a detector window; iv) detection of gammas by the detector. This paper discusses the theory and results of the first three steps for the case of a cargo container with a sphere of HEU in third-density water cargo. To complete the first step, a response-function formulation has been developed tomore » calculate the subcritical multiplication and neutron flux distribution. Response coefficients are pre-calculated using the MCNP5 Monte Carlo code. The second step uses the calculated neutron flux distribution and Bugle-96 (n, 7) cross sections to find the resulting gamma source distribution. In the third step the gamma source distribution is coupled with a pre-calculated adjoint function to determine the gamma current at a detector window. The AIMS (Active Interrogation for Monitoring Special-Nuclear-Materials) software has been written to output the gamma current for a source-detector assembly scanning across a cargo container using the pre-calculated values and taking significantly less time than a reference MCNP5 calculation. (authors)« less
Simulation Of A Photofission-Based Cargo Interrogation System
DOE Office of Scientific and Technical Information (OSTI.GOV)
King, Michael; Gozani, Tsahi; Stevenson, John
A comprehensive model has been developed to characterize and optimize the detection of Bremsstrahlung x-ray induced fission signatures from nuclear materials hidden in cargo containers. An effective active interrogation system should not only induce a large number of fission events but also efficiently detect their signatures. The proposed scanning system utilizes a 9-MV commercially available linear accelerator and the detection of strong fission signals i.e. delayed gamma rays and prompt neutrons. Because the scanning system is complex and the cargo containers are large and often highly attenuating, the simulation method segments the model into several physical steps, representing each changemore » of radiation particle. Each approximation is carried-out separately, resulting in a major reduction in computational time and a significant improvement in tally statistics. The model investigates the effect on the fission rate and detection rate by various cargo types, densities and distributions. Hydrogenous and metallic cargos, homogeneous and heterogeneous, as well as various locations of the nuclear material inside the cargo container were studied. We will show that for the photofission-based interrogation system simulation, the final results are not only in good agreement with a full, single-step simulation but also with experimental results, further validating the full-system simulation.« less
Miniature fiber Bragg grating sensor interrogator (FBG-Transceiver) system
NASA Astrophysics Data System (ADS)
Mendoza, Edgar A.; Kempen, Cornelia; Lopatin, Craig
2007-04-01
This paper describes recent progress conducted towards the development of a miniature fiber Bragg grating sensor interrogator (FBG-Transceiver TM) system based on multi-channel integrated optic sensor (InOSense TM) microchip technology. The hybrid InOSense TM microchip technology enables the integration of all of the functionalities, both passive and active, of conventional bench top FBG sensor interrogator systems, packaged in a miniaturized, low power operation, 2-cm x 5-cm package suitable for the long-term structural health monitoring in applications where size, weight, and power are critical for operation. The FBG-Transceiver system uses active optoelectronic components monolithically integrated to the InOSense TM microchip, a microprocessor controlled signal processing electronics board capable of processing the FBG sensors signals related to stress-strain and temperature as well as vibration and acoustics. The FBG-Transceiver TM system represents a new, reliable, highly robust technology that can be used to accurately monitor the status of an array of distributed fiber optic Bragg grating sensors installed in critical infrastructures. Its miniature package, low power operation, and state-of-the-art data communications architecture, all at a very affordable price makes it a very attractive solution for a large number of SHM/NDI applications in aerospace, naval and maritime industry, civil structures like bridges, buildings and dams, the oil and chemical industry, and for homeland security applications. The miniature, cost-efficient FBG-Transceiver TM system is poised to revolutionize the field of structural health monitoring and nondestructive inspection market. The sponsor of this program is NAVAIR under a DOD SBIR contract.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McElroy, Robert Dennis; Cleveland, Steven L.
The 235U mass assay of bulk uranium items, such as oxide canisters, fuel pellets, and fuel assemblies, is not achievable by traditional gamma-ray assay techniques due to the limited penetration of the item by the characteristic 235U gamma rays. Instead, fast neutron interrogation methods such as active neutron coincidence counting must be used. For international safeguards applications, the most commonly used active neutron systems, the Active Well Coincidence Counter (AWCC), Uranium Neutron Collar (UNCL) and 252Cf Shuffler, rely on fast neutron interrogation using an isotopic neutron source [i.e., 252Cf or Am(Li)] to achieve better measurement accuracies than are possible usingmore » gamma-ray techniques for high-mass, high-density items. However, the Am(Li) sources required for the AWCC and UNCL systems are no longer manufactured, and newly produced systems rely on limited supplies of sources salvaged from disused instruments. The 252Cf shuffler systems rely on the use of high-output 252Cf sources, which while still available have become extremely costly for use in routine operations and require replacement every five to seven years. Lack of a suitable alternative neutron interrogation source would leave a potentially significant gap in the safeguarding of uranium processing facilities. In this work, we made use of Oak Ridge National Laboratory’s (ORNL’s) Large Volume Active Well Coincidence Counter (LV-AWCC) and a commercially available deuterium-deuterium (D-D) neutron generator to examine the potential of the D-D neutron generator as an alternative to the isotopic sources. We present the performance of the LV-AWCC with D-D generator for the assay of 235U based on the results of Monte Carlo N-Particle (MCNP) simulations and measurements of depleted uranium (DU), low enriched uranium (LEU), and highly enriched uranium (HEU) items.« less
Single transmission line interrogated multiple channel data acquisition system
Fasching, George E.; Keech, Jr., Thomas W.
1980-01-01
A single transmission line interrogated multiple channel data acquisition system is provided in which a plurality of remote station/sensor circuits each monitors a specific process variable and each transmits measurement values over a single transmission line to a master interrogating station when addressed by said master interrogating station. Typically, as many as 330 remote stations may be parallel connected to the transmission line which may exceed 7,000 feet. The interrogation rate is typically 330 stations/second. The master interrogating station samples each station according to a shared, charging transmit-receive cycle. All remote station address signals, all data signals from the remote stations/sensors and all power for all of the remote station/sensors are transmitted via a single continuous terminated coaxial cable. A means is provided for periodically and remotely calibrating all remote sensors for zero and span. A provision is available to remotely disconnect any selected sensor station from the main transmission line.
Developing and evaluating prediactive strategies to elucidate the mode of biological activity of environmental chemicals is a major objective of the concerted efforts of the US-EPA's computational toxicology program.
NASA Technical Reports Server (NTRS)
Woodward, Stanley E.; Taylor, Bryant D.
2010-01-01
A system for wirelessly measuring the volume of fluid in tanks at non-horizontal orientation is predicated upon two technologies developed at Langley Research Center. The first is a magnetic field response recorder that powers and interrogates magnetic field response sensors [ Magnetic Field Response Measurement Acquisition System, (LAR-16908), NASA Tech Briefs, Vol. 30, No. 6 (June 2006), page 28]. Magnetic field response sensors are a class of sensors that are powered via oscillating magnetic fields and when electrically active respond with their own magnetic fields whose attributes are dependent upon the magnitude of the physical quantity being measured. The response recorder facilitates the use of the second technology, which is a magnetic field response fluid-level sensor ["Wireless Fluid- Level Sensors for Harsh Environments," (LAR-17155), NASA Tech Briefs, Vol. 33, No. 4 (April 2009), page 30]. The method for powering and interrogating the sensors allows them to be completely encased in materials (Fig. 1) that are chemically resilient to the fluid being measured, thereby facilitating measurement of substances (e.g., acids, petroleum, cryogenic, caustic, and the like) that would normally destroy electronic circuitry. When the sensors are encapsulated, no fluid (or fluid vapor) is exposed to any electrical component of the measurement system. There is no direct electrical line from the vehicle or plant power into a fuel container. The means of interrogating and powering the sensors can be completely physically and electrically isolated from the fuel and vapors by placing the sensor on the other side of an electrically non-conductive bulkhead (Fig. 2). These features prevent the interrogation system and its electrical components from becoming an ignition source.
Lee, Hyung-Seok; Lee, Hwi Don; Kim, Hyo Jin; Cho, Jae Du; Jeong, Myung Yung; Kim, Chang-Seok
2014-01-01
A linearized wavelength-swept thermo-optic laser chip was applied to demonstrate a fiber Bragg grating (FBG) sensor interrogation system. A broad tuning range of 11.8 nm was periodically obtained from the laser chip for a sweep rate of 16 Hz. To measure the linear time response of the reflection signal from the FBG sensor, a programmed driving signal was directly applied to the wavelength-swept laser chip. The linear wavelength response of the applied strain was clearly extracted with an R-squared value of 0.99994. To test the feasibility of the system for dynamic measurements, the dynamic strain was successfully interrogated with a repetition rate of 0.2 Hz by using this FBG sensor interrogation system. PMID:25177803
Sampayan, Stephen E.
2016-11-22
Apparatus, systems, and methods that provide an X-ray interrogation system having a plurality of stationary X-ray point sources arranged to substantially encircle an area or space to be interrogated. A plurality of stationary detectors are arranged to substantially encircle the area or space to be interrogated, A controller is adapted to control the stationary X-ray point sources to emit X-rays one at a time, and to control the stationary detectors to detect the X-rays emitted by the stationary X-ray point sources.
Mittal, Suneet; Younge, Kevin; King-Ellison, Kelly; Hammill, Eric; Stein, Kenneth
2016-08-01
Patients with a cardiac implantable electronic device (CIED) often need device interrogation in an in-hospital environment. A diagnosis-only, remote interrogation device and process for CIED interrogation was developed to address this situation. Here, we describe our initial clinical experience with this system. The LATITUDE Consult Communicator is a stand-alone interrogation-only device used to read the patient's implanted CIED. Once retrieved, the data are securely transmitted via an analog phone line to a central server. The clinician can request a review of the transmitted data at any time. Following FDA approval, we determined the usage and performance of the system. Communicators (n = 53) were installed in 42 hospital facilities. The most common location was in the emergency department (n = 32, 60 %). There were 509 discreet transmissions, which were categorized as follows: no arrhythmia episodes in the past 72 h and no out of range measurements (n = 174, 34 %); arrhythmia episodes in past 72 h but no out of range measurements (n = 170, 33 %); and further review recommended (n = 130, 26 %). (In 35 [7 %] instances, interrogation without analysis was requested.) The further review interrogations were then sub-divided into those of a non-urgent and urgent nature. Overall, only 53 (10 %) of the 509 transmissions were classified as urgent. Clinicians had access to full technical consultation in ≤15 min in 89 % of instances. Our data demonstrate the feasibility of a new diagnosis-only, remote interrogation device and remote evaluation process for the interrogation of CIEDs in an in-hospital environment.
Research on the demodulation techniques of long-period fiber gratings strain sensing with low cost
NASA Astrophysics Data System (ADS)
Wang, Qingwei; Liu, Yueming; Tian, Weijian; Feng, Guilan
2012-10-01
The working principle of LPFG(Long-Period Fiber Grating) is based on coupling effect between propagating core-mode and co-propagating cladding-modes. The effective refractive index of cladding-modes could be obviously influenced by the environmental changes resulting in LPFG more sensitive than FBG (Fiber Bragg Grating) in sensing areas, such as temperature, strain, concentration, bending and etc. LPFG should have more potential in the field of sensors compared with FBG. One of the challenges in using LPFG for environmental sensing is how to interrogate the signal from the LPFG transmission spectrum, due to the large spectral range of the resonant dip. Nowadays the application of LPFG is normally limited in signal interrogation of FBG as optical edge filter. The signal interrogation of LPFG itself needs further research. Presently research on signal interrogation of fiber grating focuses on wavelength interrogation. The aim of wavelength interrogation is to get the wavelength shift caused by environmental change. To solve these problems, a kind of strain sensing interrogation technique for LPFG with low-cost based on tunable FBGs has been developed. Comparing with the method using Fabry-Perot cavity, tunable FBGs can lower the cost with the guarantee of sensing precision. The cost is further lowered without using expensive optical instruments such as optical switch. The problem of temperature cross-sensitivity was solved by using reference gratings. An experiment was performed to demonstrate the interrogation system. And in the experiment, the sensing signal of LPFG applied 0-1300μɛ was successfully interrogated. The results of the interrogation system and OSA are similar.
Theory and Performance of AIMS for Active Interrogation
NASA Astrophysics Data System (ADS)
Walters, William J.; Royston, Katherine E. K.; Haghighat, Alireza
2014-06-01
A hybrid Monte Carlo and deterministic methodology has been developed for application to active interrogation systems. The methodology consists of four steps: i) determination of neutron flux distribution due to neutron source transport and subcritical multiplication; ii) generation of gamma source distribution from (n, γ) interactions; iii) determination of gamma current at a detector window; iv) detection of gammas by the detector. This paper discusses the theory and results of the first three steps for the case of a cargo container with a sphere of HEU in third-density water. In the first step, a response-function formulation has been developed to calculate the subcritical multiplication and neutron flux distribution. Response coefficients are pre-calculated using the MCNP5 Monte Carlo code. The second step uses the calculated neutron flux distribution and Bugle-96 (n, γ) cross sections to find the resulting gamma source distribution. Finally, in the third step the gamma source distribution is coupled with a pre-calculated adjoint function to determine the gamma flux at a detector window. A code, AIMS (Active Interrogation for Monitoring Special-Nuclear-materials), has been written to output the gamma current for an source-detector assembly scanning across the cargo using the pre-calculated values and takes significantly less time than a reference MCNP5 calculation.
Progress in miniaturization of a multichannel optical fiber Bragg grating sensor interrogator
NASA Astrophysics Data System (ADS)
Lopatin, Craig M.; Mahmood, Shah; Mendoza, Edgar; Moslehi, Behzad; Black, Richard; Chau, Kelvin; Oblea, Levy
2007-07-01
An effort to develop a miniaturized multichannel optical fiber Bragg grating sensor interrogator was initiated in 2006 under the Small Business Innovative Research (SBIR) program. The goal was to develop an interrogator that would be sufficiently small and light to be incorporated into a health monitoring system for use on tactical missiles. Two companies, Intelligent Fiber Optic Systems Corporation (IFOS) and Redondo Optics, were funded in Phase I, and this paper describes the prototype interrogators that were developed. The two companies took very different approaches: IFOS focused on developing a unit that would have a high channel count and high resolution, using off-the-shelf components, while Redondo Optics chose to develop a unit that would be very small and lightweight, using custom designed integrated optical chips. It is believed that both approaches will result in interrogators that will be significantly small, lighter, and possibly even more precise than what is currently commercially available. This paper will also briefly describe some of the sensing concepts that may be used to interrogate the health of the solid rocket motors used in many missile systems. The sponsor of this program was NAVAIR PMA 280.
Burgess, Mark; Hernández-Burgos, Kenneth; Cheng, Kevin J; Moore, Jeffrey S; Rodríguez-López, Joaquín
2016-06-21
Elucidating the impact of interactions between the electrolyte and electroactive species in redox active polymers is key to designing better-performing electrodes for electrochemical energy storage and conversion. Here, we present on the improvement of the electrochemical activity of poly(para-nitrostyrene) (PNS) in solution and as a film by exploiting the ionic interactions between reduced PNS and K(+), which showed increased reactivity when compared to tetrabutylammonium (TBA(+))- and Li(+)-containing electrolytes. While cyclic voltammetry enabled the study of the effects of cations on the electrochemical reversibility and the reduction potential of PNS, scanning electrochemical microscopy (SECM) provided new tools to probe the ionic and redox reactivity of this system. Using an ion-sensitive Hg SECM tip allowed to probe the ingress of ions into PNS redox active films, while surface interrogation SECM (SI-SECM) measured the specific kinetics of PNS and a solution phase mediator in the presence of the tested electrolytes. SI-SECM measurements illustrated that the interrogation kinetics of PNS in the presence of K(+) compared to TBA(+) and Li(+) are greatly enhanced under the same surface concentration of adsorbed radical anion, exhibiting up to a 40-fold change in redox kinetics. We foresee using this new application of SECM methods for elucidating optimal interactions that enhance polymer reactivity for applications in redox flow batteries.
48 CFR 237.173 - Prohibition on interrogation of detainees by contractor personnel.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Prohibition on interrogation of detainees by contractor personnel. 237.173 Section 237.173 Federal Acquisition Regulations... SERVICE CONTRACTING Service Contracts-General 237.173 Prohibition on interrogation of detainees by...
48 CFR 237.173 - Prohibition on interrogation of detainees by contractor personnel.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Prohibition on interrogation of detainees by contractor personnel. 237.173 Section 237.173 Federal Acquisition Regulations... SERVICE CONTRACTING Service Contracts-General 237.173 Prohibition on interrogation of detainees by...
48 CFR 237.173 - Prohibition on interrogation of detainees by contractor personnel.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Prohibition on interrogation of detainees by contractor personnel. 237.173 Section 237.173 Federal Acquisition Regulations... SERVICE CONTRACTING Service Contracts-General 237.173 Prohibition on interrogation of detainees by...
48 CFR 237.173 - Prohibition on interrogation of detainees by contractor personnel.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Prohibition on interrogation of detainees by contractor personnel. 237.173 Section 237.173 Federal Acquisition Regulations... SERVICE CONTRACTING Service Contracts-General 237.173 Prohibition on interrogation of detainees by...
Improved Fission Neutron Data Base for Active Interrogation of Actinides
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pozzi, Sara; Czirr, J. Bart; Haight, Robert
2013-11-06
This project will develop an innovative neutron detection system for active interrogation measurements. Many active interrogation methods to detect fissionable material are based on the detection of neutrons from fission induced by fast neutrons or high-energy gamma rays. The energy spectrum of the fission neutrons provides data to identify the fissionable isotopes and materials such as shielding between the fissionable material and the detector. The proposed path for the project is as follows. First, the team will develop new neutron detection systems and algorithms by Monte Carlo simulations and bench-top experiments. Next, They will characterize and calibrate detection systems bothmore » with monoenergetic and white neutron sources. Finally, high-fidelity measurements of neutron emission from fissions induced by fast neutrons will be performed. Several existing fission chambers containing U-235, Pu-239, U-238, or Th-232 will be used to measure the neutron-induced fission neutron emission spectra. The challenge for making confident measurements is the detection of neutrons in the energy ranges of 0.01 – 1 MeV and above 8 MeV, regions where the basic data on the neutron energy spectrum emitted from fission is least well known. In addition, improvements in the specificity of neutron detectors are required throughout the complete energy range: they must be able to clearly distinguish neutrons from other radiations, in particular gamma rays and cosmic rays. The team believes that all of these challenges can be addressed successfully with emerging technologies under development by this collaboration. In particular, the collaboration will address the area of fission neutron emission spectra for isotopes of interest in the advanced fuel cycle initiative (AFCI).« less
Pope, Kenneth S
2011-01-01
After 9-11, the United States began interrogating detainees at settings such as Abu Ghraib, Bagram, and Guantanamo. The American Psychological Association (APA) supported psychologists' involvement in interrogations, adopted formal policies, and made an array of public assurances. This article's purpose is to highlight key APA decisions, policies, procedures, documents, and public statements in urgent need of rethinking and to suggest questions that may be useful in a serious assessment, such as, "However well intended, were APA's interrogation policies ethically sound?"; "Were they valid, realistic, and able to achieve their purpose?"; "Were other approaches available that would address interrogation issues more directly, comprehensively, and actively, that were more ethically and scientifically based, and that would have had a greater likelihood of success?"; and "Should APA continue to endorse its post-9-11 detainee interrogation policies?"
Fiber-MZI-based FBG sensor interrogation: comparative study with a CCD spectrometer.
Das, Bhargab; Chandra, Vikash
2016-10-10
We present an experimental comparative study of the two most commonly used fiber Bragg grating (FBG) sensor interrogation techniques: a charge-coupled device (CCD) spectrometer and a fiber Mach-Zehnder interferometer (F-MZI). Although the interferometric interrogation technique is historically known to offer the highest sensitivity measurements, very little information exists regarding how it compares with the current commercially available spectral-characteristics-based interrogation systems. It is experimentally established here that the performance of a modern-day CCD spectrometer interrogator is very close to a F-MZI interrogator with the capability of measuring Bragg wavelength shifts with sub-picometer-level accuracy. The results presented in this research study can further be used as a guideline for choosing between the two FBG sensor interrogator types for small-amplitude dynamic perturbation measurements down to nano-level strain.
Kumar, Saurabh; Amrutur, Bharadwaj; Asokan, Sundarrajan
2018-02-01
Fiber Bragg Grating (FBG) sensors have become popular for applications related to structural health monitoring, biomedical engineering, and robotics. However, for successful large scale adoption, FBG interrogation systems are as important as sensor characteristics. Apart from accuracy, the required number of FBG sensors per fiber and the distance between the device in which the sensors are used and the interrogation system also influence the selection of the interrogation technique. For several measurement devices developed for applications in biomedical engineering and robotics, only a few sensors per fiber are required and the device is close to the interrogation system. For these applications, interrogation systems based on InGaAs linear detector arrays provide a good choice. However, their resolution is dependent on the algorithms used for curve fitting. In this work, a detailed analysis of the choice of algorithm using the Gaussian approximation for the FBG spectrum and the number of pixels used for curve fitting on the errors is provided. The points where the maximum errors occur have been identified. All comparisons for wavelength shift detection have been made against another interrogation system based on the tunable swept laser. It has been shown that maximum errors occur when the wavelength shift is such that one new pixel is included for curve fitting. It has also been shown that an algorithm with lower computation cost compared to the more popular methods using iterative non-linear least squares estimation can be used without leading to the loss of accuracy. The algorithm has been implemented on embedded hardware, and a speed-up of approximately six times has been observed.
NASA Astrophysics Data System (ADS)
Kumar, Saurabh; Amrutur, Bharadwaj; Asokan, Sundarrajan
2018-02-01
Fiber Bragg Grating (FBG) sensors have become popular for applications related to structural health monitoring, biomedical engineering, and robotics. However, for successful large scale adoption, FBG interrogation systems are as important as sensor characteristics. Apart from accuracy, the required number of FBG sensors per fiber and the distance between the device in which the sensors are used and the interrogation system also influence the selection of the interrogation technique. For several measurement devices developed for applications in biomedical engineering and robotics, only a few sensors per fiber are required and the device is close to the interrogation system. For these applications, interrogation systems based on InGaAs linear detector arrays provide a good choice. However, their resolution is dependent on the algorithms used for curve fitting. In this work, a detailed analysis of the choice of algorithm using the Gaussian approximation for the FBG spectrum and the number of pixels used for curve fitting on the errors is provided. The points where the maximum errors occur have been identified. All comparisons for wavelength shift detection have been made against another interrogation system based on the tunable swept laser. It has been shown that maximum errors occur when the wavelength shift is such that one new pixel is included for curve fitting. It has also been shown that an algorithm with lower computation cost compared to the more popular methods using iterative non-linear least squares estimation can be used without leading to the loss of accuracy. The algorithm has been implemented on embedded hardware, and a speed-up of approximately six times has been observed.
NASA Astrophysics Data System (ADS)
Lopez-Aldaba, A.; Auguste, J.-L.; Jamier, R.; Roy, P.; Lopez-Amo, M.
2017-04-01
In this paper, a new sensor system for simultaneous and quasi-independent strain and temperature measurements is presented. The interrogation of the sensing head has been carried out by monitoring the FFT phase variations of two of the microstructured optical fiber (MOF) cavity interference frequencies. This method is independent of the signal amplitude and also avoids the need to track the wavelength evolution in the spectrum, which can be a handicap when there are multiple interference frequency components with different sensitivities. The sensor is operated within a range of temperature of 30°C-75°C, and 380μɛ of maximum strain were applied; being the sensitivities achieved of 127.5pm/°C and -19.1pm/μɛ respectively. Because the system uses an optical interrogator as unique active element, the system presents a cost-effective feature.
NASA Astrophysics Data System (ADS)
Clemett, Ceri D.; Martin, Philip N.; Hill, Cassie; Threadgold, James R.; Maddock, Robert C.; Campbell, Ben; O'Malley, John; Woolf, Richard S.; Phlips, Bernard F.; Hutcheson, Anthony L.; Wulf, Eric A.; Zier, Jacob C.; Jackson, Stuart L.; Commisso, Robert J.; Schumer, Joseph W.
2015-04-01
Active interrogation is a method used to enhance the likelihood of detection of shielded special nuclear material (SNM); an external source of radiation is used to interrogate a target and to stimulate fission within any SNM present. Radiation produced by the fission process can be detected and used to infer the presence of the SNM. The Atomic Weapons Establishment (AWE) and the Naval Research Laboratory (NRL) have carried out a joint experimental study into the use of single pulse, high-intensity sources of bremsstrahlung x-rays and D(γb, n)H photoneutrons in an active interrogation system. The source was operated in both x-ray-only and mixed x-ray/photoneutron modes, and was used to irradiate a depleted uranium (DU) target which was enclosed by up to 150 g·cm - 2 of steel shielding. Resulting radiation signatures were measured by a suite of over 80 detectors and the data used to characterise detectable fission signatures as a function of the areal mass of the shielding. This paper describes the work carried out and discusses data collected with 3He proportional counters, NaI(Tl) scintillators and Eljen EJ-309 liquid scintillators. Results with the x-ray-only source demonstrate detection ( > 3\\sigmab) of the DU target through a minimum of 113 g·cm - 2 of steel, dropping to 85 g·cm- 2 when using a mixed x-ray/photoneutron source. The 3He proportional counters demonstrate detection ( > 3\\sigmab) of the DU target through the maximum 149. 7 g·cm - 2 steel shielding deployed for both photon and mixed x-ray/photoneutron sources.
The phase interrogation method for optical fiber sensor by analyzing the fork interference pattern
NASA Astrophysics Data System (ADS)
Lv, Riqing; Qiu, Liqiang; Hu, Haifeng; Meng, Lu; Zhang, Yong
2018-02-01
The phase interrogation method for optical fiber sensor is proposed based on the fork interference pattern between the orbital angular momentum beam and plane wave. The variation of interference pattern with phase difference between the two light beams is investigated to realize the phase interrogation. By employing principal component analysis method, the features of the interference pattern can be extracted. Moreover, the experimental system is designed to verify the theoretical analysis, as well as feasibility of phase interrogation. In this work, the Mach-Zehnder interferometer was employed to convert the strain applied on sensing fiber to the phase difference between the reference and measuring paths. This interrogation method is also applicable for the measurements of other physical parameters, which can produce the phase delay in optical fiber. The performance of the system can be further improved by employing highlysensitive materials and fiber structures.
Are the American Psychological Association’s Detainee Interrogation Policies Ethical and Effective?
Pope, Kenneth S.
2011-01-01
After 9–11, the United States began interrogating detainees at settings such as Abu Ghraib, Bagram, and Guantanamo. The American Psychological Association (APA) supported psychologists’ involvement in interrogations, adopted formal policies, and made an array of public assurances. This article’s purpose is to highlight key APA decisions, policies, procedures, documents, and public statements in urgent need of rethinking and to suggest questions that may be useful in a serious assessment, such as, “However well intended, were APA’s interrogation policies ethically sound?”; “Were they valid, realistic, and able to achieve their purpose?”; “Were other approaches available that would address interrogation issues more directly, comprehensively, and actively, that were more ethically and scientifically based, and that would have had a greater likelihood of success?”; and “Should APA continue to endorse its post-9–11 detainee interrogation policies?” PMID:22096660
DOT National Transportation Integrated Search
1976-07-01
The Transportation Systems Center is conducting a progrm to develop a surface surveillance sensor that uses replies from ATCRBS tansponders. The operation of this system can be affected by surface interrogations at major airports where such a system ...
Interrogator system for identifying electrical circuits
Jatko, W.B.; McNeilly, D.R.
1988-04-12
A system for interrogating electrical leads to correctly ascertain the identity of equipment attached to remote ends of the leads is disclosed. The system includes a source of a carrier signal generated in a controller/receiver to be sent over the leads and an identifier unit at the equipment. The identifier is activated by command of the carrier and uses a portion of the carrier to produce a supply voltage. Each identifier is uniquely programmed for a specific piece of equipment, and causes the impedance of the circuit to be modified whereby the carrier signal is modulated according to that program. The modulation can be amplitude, frequency or phase modulation. A demodulator in the controller/receiver analyzes the modulated carrier signal, and if a verified signal is recognized displays and/or records the information. This information can be utilized in a computer system to prepare a wiring diagram of the electrical equipment attached to specific leads. Specific circuit values are given for amplitude modulation, and the system is particularly described for use with thermocouples. 6 figs.
Interrogator system for identifying electrical circuits
Jatko, William B.; McNeilly, David R.
1988-01-01
A system for interrogating electrical leads to correctly ascertain the identity of equipment attached to remote ends of the leads. The system includes a source of a carrier signal generated in a controller/receiver to be sent over the leads and an identifier unit at the equipment. The identifier is activated by command of the carrier and uses a portion of the carrier to produce a supply voltage. Each identifier is uniquely programmed for a specific piece of equipment, and causes the impedance of the circuit to be modified whereby the carrier signal is modulated according to that program. The modulation can be amplitude, frequency or phase modulation. A demodulator in the controller/receiver analyzes the modulated carrier signal, and if a verified signal is recognized displays and/or records the information. This information can be utilized in a computer system to prepare a wiring diagram of the electrical equipment attached to specific leads. Specific circuit values are given for amplitude modulation, and the system is particularly described for use with thermocouples.
Development of fiber optic sensing interrogators for launchers
NASA Astrophysics Data System (ADS)
Plattner, M. P.; Buck, T. C.; Eder, B.; Reutlinger, A.; McKenzie, I.
2017-11-01
We present our work about the development of two complementary interrogation schemes based on fiber optic sensing for the use of structural and thermal monitoring of Ariane launchers. The advantages of fiber optic sensing in particular light-weight, immunity to electromagnetic interferences and the possibility of sensor distribution along optical fibers are driving factors for utilization of this technology in space crafts [1]. The edge-filter (EF) and scanning-laser (SL) interrogators for determination of the mean wavelength of fiber Bragg grating (FBG) sensors have been implemented as two separate demonstrators. Within this paper we describe the functional principles of both interrogators. Furthermore we present test results where the developed systems have been used for readout of FBG sensors which are implemented in an Ariane structural demonstrator during thermal, thermal-vacuum and vibration tests. Functionality of both systems is demonstrated and their potential for further development towards space qualified systems is shown. Since the performance characteristics of the two systems are different from each other, they are dedicated for different sensing applications on a launcher. The EF sensor interrogator provides a sample rate of 20 kHz at a number of 4 connected sensors and supports parallel readout and aliasing free operation. Therefore it is best suited for high priority measurement. Structural monitoring which requires the acquisition of real time sensor information in order to support control of the launcher is one operation area for a future EF system. The SL interrogator provides an overall measurement rate of 1 kHz at a number of 24 connected sensors distributed on three sensor channels. It can be adapted to any sensors that have design wavelengths lying within the output spectrum of the laser diode. Furthermore the number of overall sensors to be read out with this system can be adapted easily. Thermal mapping of satellite panels is one possible future application for the SL interrogator.
Ask Systems: Interrogative Access to Multiple Ways of Thinking
ERIC Educational Resources Information Center
Jonassen, David H.
2011-01-01
The purpose of this paper is to familiarize instructional designers and researchers with a useful design and research paradigm known as "Ask Systems." Ask Systems are interrogative interfaces to information and learning environments that model conversations with a skilled, reflective practitioner (Schon, The reflective practitioner, "1983") or…
Obenhaus, Horst A; Rozov, Andrei; Bertocchi, Ilaria; Tang, Wannan; Kirsch, Joachim; Betz, Heinrich; Sprengel, Rolf
2016-01-01
The causal interrogation of neuronal networks involved in specific behaviors requires the spatially and temporally controlled modulation of neuronal activity. For long-term manipulation of neuronal activity, chemogenetic tools provide a reasonable alternative to short-term optogenetic approaches. Here we show that virus mediated gene transfer of the ivermectin (IVM) activated glycine receptor mutant GlyRα1 (AG) can be used for the selective and reversible silencing of specific neuronal networks in mice. In the striatum, dorsal hippocampus, and olfactory bulb, GlyRα1 (AG) promoted IVM dependent effects in representative behavioral assays. Moreover, GlyRα1 (AG) mediated silencing had a strong and reversible impact on neuronal ensemble activity and c-Fos activation in the olfactory bulb. Together our results demonstrate that long-term, reversible and re-inducible neuronal silencing via GlyRα1 (AG) is a promising tool for the interrogation of network mechanisms underlying the control of behavior and memory formation.
DOT National Transportation Integrated Search
2015-10-31
In 2012, the Navy requested spectrum certification for the shipboard AN/UPX-41(C) Digital Interrogator System, Software Version 5.5 with Mode 5. Current operating conditions for the Navys AN/UPX-41(C) are the same as restrictions imposed on the AN...
Rodent wearable ultrasound system for wireless neural recording.
Piech, David K; Kay, Joshua E; Boser, Bernhard E; Maharbiz, Michel M
2017-07-01
Advances in minimally-invasive, distributed biological interface nodes enable possibilities for networks of sensors and actuators to connect the brain with external devices. The recent development of the neural dust sensor mote has shown that utilizing ultrasound backscatter communication enables untethered sub-mm neural recording devices. These implanted sensor motes require a wearable external ultrasound interrogation device to enable in-vivo, freely-behaving neural interface experiments. However, minimizing the complexity and size of the implanted sensors shifts the power and processing burden to the external interrogator. In this paper, we present an ultrasound backscatter interrogator that supports real-time backscatter processing in a rodent-wearable, completely wireless device. We demonstrate a generic digital encoding scheme which is intended for transmitting neural information. The system integrates a front-end ultrasonic interface ASIC with off-the-shelf components to enable a highly compact ultrasound interrogation device intended for rodent neural interface experiments but applicable to other model systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, Thomas Martin; Patton, Bruce W
The detection and interdiction of special nuclear material (SNM) is still a high-priority focus area for many organizations around the world. One method that is commonly considered a leading candidate in the detection of SNM is active interrogation (AI). AI is different from its close relative, passive interrogation, in that an active source is used to enhance or create a detectable signal (usually fission) from SNM, particularly in shielded scenarios or scenarios where the SNM has a low activity. The use of AI thus makes the detection of SNM easier or, in some scenarios, even enables previously impossible detection. Inmore » this work the signal from prompt neutrons and photons as well as delayed neutrons and photons will be combined, as is typically done in AI. In previous work AI has been evaluated experimentally and computationally. However, for the purposes of this work, past scenarios are considered lightly shielded and tightly coupled spatially. At most, the previous work interrogated the contents of one standard cargo container (2.44 x 2.60 x 6.10 m) and the source and detector were both within a few meters of the object being interrogated. A few examples of this type of previous work can be found in references 1 and 2. Obviously, more heavily shielded AI scenarios will require larger source intensities, larger detector surface areas (larger detectors or more detectors), greater detector efficiencies, longer count times, or some combination of these.« less
Ultrafast Fiber Bragg Grating Interrogation for Sensing in Detonation and Shock Wave Experiments.
Rodriguez, George; Gilbertson, Steve M
2017-01-27
Chirped fiber Bragg grating (CFBG) sensors coupled to high speed interrogation systems are described as robust diagnostic approaches to monitoring shock wave and detonation front propagation tracking events for use in high energy density shock physics applications. Taking advantage of the linear distributed spatial encoding of the spectral band in single-mode CFBGs, embedded fiber systems and associated photonic interrogation methodologies are shown as an effective approach to sensing shock and detonation-driven loading processes along the CFBG length. Two approaches, one that detects spectral changes in the integrated spectrum of the CFBG and another coherent pulse interrogation approach that fully resolves its spectral response, shows that 100-MHz-1-GHz interrogation rates are possible with spatial resolution along the CFBG in the 50 µm to sub-millimeter range depending on the combination of CFBG parameters (i.e., length, chirp rate, spectrum) and interrogator design specifics. Results from several dynamic tests are used to demonstrate the performance of these high speed systems for shock and detonation propagation tracking under strong and weak shock pressure loading: (1) linear detonation front tracking in the plastic bonded explosive (PBX) PBX-9501; (2) tracking of radial decaying shock with crossover to non-destructive CFBG response; (3) shock wave tracking along an aluminum cylinder wall under weak loading accompanied by dynamic strain effects in the CFBG sensor.
Ultrafast Fiber Bragg Grating Interrogation for Sensing in Detonation and Shock Wave Experiments
Rodriguez, George; Gilbertson, Steve M.
2017-01-01
Chirped fiber Bragg grating (CFBG) sensors coupled to high speed interrogation systems are described as robust diagnostic approaches to monitoring shock wave and detonation front propagation tracking events for use in high energy density shock physics applications. Taking advantage of the linear distributed spatial encoding of the spectral band in single-mode CFBGs, embedded fiber systems and associated photonic interrogation methodologies are shown as an effective approach to sensing shock and detonation-driven loading processes along the CFBG length. Two approaches, one that detects spectral changes in the integrated spectrum of the CFBG and another coherent pulse interrogation approach that fully resolves its spectral response, shows that 100-MHz–1-GHz interrogation rates are possible with spatial resolution along the CFBG in the 50 μm to sub-millimeter range depending on the combination of CFBG parameters (i.e., length, chirp rate, spectrum) and interrogator design specifics. Results from several dynamic tests are used to demonstrate the performance of these high speed systems for shock and detonation propagation tracking under strong and weak shock pressure loading: (1) linear detonation front tracking in the plastic bonded explosive (PBX) PBX-9501; (2) tracking of radial decaying shock with crossover to non-destructive CFBG response; (3) shock wave tracking along an aluminum cylinder wall under weak loading accompanied by dynamic strain effects in the CFBG sensor. PMID:28134819
Ultrafast Fiber Bragg Grating Interrogation for Sensing in Detonation and Shock Wave Experiments
Rodriguez, George; Gilbertson, Steve Michael
2017-01-27
Chirped fiber Bragg grating (CFBG) sensors coupled to high speed interrogation systems are described as robust diagnostic approaches to monitoring shock wave and detonation front propagation tracking events for use in high energy density shock physics applications. Taking advantage of the linear distributed spatial encoding of the spectral band in single-mode CFBGs, embedded fiber systems and associated photonic interrogation methodologies are shown as an effective approach to sensing shock and detonation-driven loading processes along the CFBG length. Two approaches, one that detects spectral changes in the integrated spectrum of the CFBG and another coherent pulse interrogation approach that fully resolvesmore » its spectral response, shows that 100-MHz–1-GHz interrogation rates are possible with spatial resolution along the CFBG in the 50 µm to sub-millimeter range depending on the combination of CFBG parameters (i.e., length, chirp rate, spectrum) and interrogator design specifics. In conclusion, results from several dynamic tests are used to demonstrate the performance of these high speed systems for shock and detonation propagation tracking under strong and weak shock pressure loading: (1) linear detonation front tracking in the plastic bonded explosive (PBX) PBX-9501; (2) tracking of radial decaying shock with crossover to non-destructive CFBG response; (3) shock wave tracking along an aluminum cylinder wall under weak loading accompanied by dynamic strain effects in the CFBG sensor.« less
Resolution-improved in situ DNA hybridization detection based on microwave photonic interrogation.
Cao, Yuan; Guo, Tuan; Wang, Xudong; Sun, Dandan; Ran, Yang; Feng, Xinhuan; Guan, Bai-ou
2015-10-19
In situ bio-sensing system based on microwave photonics filter (MPF) interrogation method with improved resolution is proposed and experimentally demonstrated. A microfiber Bragg grating (mFBG) is used as sensing probe for DNA hybridization detection. Different from the traditional wavelength monitoring technique, we use the frequency interrogation scheme for resolution-improved bio-sensing detection. Experimental results show that the frequency shift of MPF notch presents a linear response to the surrounding refractive index (SRI) change over the range of 1.33 to 1.38, with a SRI resolution up to 2.6 × 10(-5) RIU, which has been increased for almost two orders of magnitude compared with the traditional fundamental mode monitoring technique (~3.6 × 10(-3) RIU). Due to the high Q value (about 27), the whole process of DNA hybridization can be in situ monitored. The proposed MPF-based bio-sensing system provides a new interrogation method over the frequency domain with improved sensing resolution and rapid interrogation rate for biochemical and environmental measurement.
Low-cost and high-resolution interrogation scheme for LPG-based temperature sensor
NASA Astrophysics Data System (ADS)
Venkata Reddy, M.; Srimannarayana, K.; Venkatappa Rao, T.; Vengal Rao, P.
2015-09-01
A low-cost and high-resolution interrogation scheme for a long-period fiber grating (LPG) temperature sensor with adjustable temperature range has been designed, developed and tested. In general LPGs are widely used as optical sensors and can be used as optical edge filters to interrogate the wavelength encoded signal from sensors such as fiber Bragg grating (FBG) by converting it into intensity modulated signal. But the interrogation of LPG sensors using FBG is a bit novel and it is to be studied experimentally. The sensor works based on measurement of shift in attenuation band of LPG corresponding to the applied temperature. The wavelength shift of LPG attenuation band is monitored using an optical spectrum analyser (OSA). Further the bulk and expensive OSA is replaced with a low-cost interrogation system that employ an FBG, photodiode and a transimpedance amplifier (TIA). The designed interrogation scheme makes the system low-cost, fast in response, and also enhances its resolution up to 0.1°C. The measurable temperature range using the proposed scheme is limited to 120 °C. However this range can be shifted within 15-450 °C by means of adjusting the Bragg wavelength of FBG.
NASA Technical Reports Server (NTRS)
Lake, Mark S.; Peterson, Lee D.; Hachkowski, M. Roman; Hinkle, Jason D.; Hardaway, Lisa R.
1998-01-01
The present paper summarizes results from an ongoing research program conducted jointly by the University of Colorado and NASA Langley Research Center since 1994. This program has resulted in general guidelines for the design of high-precision deployment mechanisms, and tests of prototype deployable structures incorporating these mechanisms have shown microdynamically stable behavior (i.e., dimensional stability to parts per million). These advancements have resulted from the identification of numerous heretofore unknown microdynamic and micromechanical response phenomena, and the development of new test techniques and instrumentation systems to interrogate these phenomena. In addition, recent tests have begun to interrogate nanomechanical response of materials and joints and have been used to develop an understanding of nonlinear nanodynamic behavior in microdynamically stable structures. The ultimate goal of these efforts is to enable nano-precision active control of micro-precision deployable structures (i.e., active control to a resolution of parts per billion).
Active detection of shielded SNM with 60-keV neutrons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hagmann, C; Dietrich, D; Hall, J
2008-07-08
Fissile materials, e.g. {sup 235}U and {sup 239}Pu, can be detected non-invasively by active neutron interrogation. A unique characteristic of fissile material exposed to neutrons is the prompt emission of high-energy (fast) fission neutrons. One promising mode of operation subjects the object to a beam of medium-energy (epithermal) neutrons, generated by a proton beam impinging on a Li target. The emergence of fast secondary neutrons then clearly indicates the presence of fissile material. Our interrogation system comprises a low-dose 60-keV neutron generator (5 x 10{sup 6}/s), and a 1 m{sup 2} array of scintillators for fast neutron detection. Preliminary experimentalmore » results demonstrate the detectability of small quantities (370 g) of HEU shielded by steel (200 g/cm{sup 2}) or plywood (30 g/cm{sup 2}), with a typical measurement time of 1 min.« less
NASA Astrophysics Data System (ADS)
Rose, P. B.; Erickson, A. S.
2015-11-01
Active interrogation of cargo containers using monoenergetic photons offers a rapid and low-dose approach to search for shielded special nuclear materials. Cherenkov detectors can be used for imaging of the cargo provided that gamma ray energies used in interrogation are well resolved, as the case in 11B(d,n-γ)12C reaction resulting in 4.4 MeV and 15.1 MeV photons. While an array of Cherenkov threshold detectors reduces low energy background from scatter while providing the ability of high contrast transmission imaging, thus confirming the presence of high-Z materials, these detectors require a special approach to energy calibration due to the lack of resolution. In this paper, we discuss the utility of Cherenkov detectors for active interrogation with monoenergetic photons as well as the results of computational and experimental studies of their energy calibration. The results of the studies with sources emitting monoenergetic photons as well as complex gamma ray spectrum sources, for example 232Th, show that calibration is possible as long as the energies of photons of interest are distinct.
Choi, Sang-Jin; Mao, Wankai; Pan, Jae-Kyung
2013-01-01
We propose and experimentally demonstrate the novel radio-frequency (RF) interrogation of a fiber Bragg grating (FBG) sensor using bidirectional modulation of a Mach-Zehnder electro-optical modulator (MZ-EOM). Based on the microwave photonic technique and active detection, the transfer function of the proposed system was obtained, and the time delay was calculated from the change in the free spectral range (FSR) at different wavelengths over the optimal measuring range. The results show that the time delay and the wavelength variation have a good linear relationship, with a gradient of 9.31 ps/nm. An actual measurement taken with a sensing FBG for temperature variation shows the relationship with a gradient of 0.93 ps/10 °C. The developed system could be used for FBG temperature or strain sensing and other multiplexed sensor applications. PMID:23820744
Autobalanced Ramsey Spectroscopy
NASA Astrophysics Data System (ADS)
Sanner, Christian; Huntemann, Nils; Lange, Richard; Tamm, Christian; Peik, Ekkehard
2018-01-01
We devise a perturbation-immune version of Ramsey's method of separated oscillatory fields. Spectroscopy of an atomic clock transition without compromising the clock's accuracy is accomplished by actively balancing the spectroscopic responses from phase-congruent Ramsey probe cycles of unequal durations. Our simple and universal approach eliminates a wide variety of interrogation-induced line shifts often encountered in high precision spectroscopy, among them, in particular, light shifts, phase chirps, and transient Zeeman shifts. We experimentally demonstrate autobalanced Ramsey spectroscopy on the light shift prone
Lee, Hsin-Cheng; Li, Chung-Tien; Chen, How-Foo; Yen, Ta-Jen
2015-11-15
We present an ultrasensitive plasmonic sensing system by introducing a nanostructured X-shaped plasmonic sensor (XPS) and measuring its localized optical properties in phase interrogation. Our tailored XPS exhibits two major resonant modes of a low-order dipole and a high-order quadrupole, between which the quadrupole resonance allows an ultrahigh sensitivity, due to its higher quality factor. Furthermore, we design an in-house common-path phase-interrogation system, in contrast to conventional wavelength-interrogation methods, to achieve greater sensing capability. The experimental measurement shows that the sensing resolution of the XPS reaches 1.15×10(-6) RIU, not only two orders of magnitude greater than the result of the controlled extinction measurement (i.e., 9.90×10(-5) RIU), but also superior than current reported plasmonic sensors.
Hidden explosives detector employing pulsed neutron and x-ray interrogation
Schultz, F.J.; Caldwell, J.T.
1993-04-06
Methods and systems for the detection of small amounts of modern, highly-explosive nitrogen-based explosives, such as plastic explosives, hidden in airline baggage. Several techniques are employed either individually or combined in a hybrid system. One technique employed in combination is X-ray imaging. Another technique is interrogation with a pulsed neutron source in a two-phase mode of operation to image both nitrogen and oxygen densities. Another technique employed in combination is neutron interrogation to form a hydrogen density image or three-dimensional map. In addition, deliberately-placed neutron-absorbing materials can be detected.
Hidden explosives detector employing pulsed neutron and x-ray interrogation
Schultz, Frederick J.; Caldwell, John T.
1993-01-01
Methods and systems for the detection of small amounts of modern, highly-explosive nitrogen-based explosives, such as plastic explosives, hidden in airline baggage. Several techniques are employed either individually or combined in a hybrid system. One technique employed in combination is X-ray imaging. Another technique is interrogation with a pulsed neutron source in a two-phase mode of operation to image both nitrogen and oxygen densities. Another technique employed in combination is neutron interrogation to form a hydrogen density image or three-dimensional map. In addition, deliberately-placed neutron-absorbing materials can be detected.
NASA Astrophysics Data System (ADS)
Keith, Rodney Lyman
Intermodal shipping containers entering the United States provide an avenue to smuggle unsecured or stolen special nuclear material (SNM). The only direct method fielded to indicate the presence of SNM is by passive photon/neutron radiation detection. Active interrogation using neutral particle beams to induce fission in SNM is a method under consideration. One by-product of fission is the creation of fragments that undergo radioactive decay over a time period on the order of tens of seconds after the initial event. The "delayed" gamma-rays emitted from these fragments over this period are considered a hallmark for the presence of SNM. A fundamental model is developed using homogenized cargos with a SNM target embedded at the center and computationally interrogated using simultaneous neutron and photon beams. Findings from analysis of the delayed gamma emissions from these experiments are intended to mitigate the effects of poor quality information about the composition and disposition of suspect cargo before examination in an active interrogation portal.
Toward microendoscopy-inspired cardiac optogenetics in vivo: technical overview and perspective
NASA Astrophysics Data System (ADS)
Klimas, Aleksandra; Entcheva, Emilia
2014-08-01
The ability to perform precise, spatially localized actuation and measurements of electrical activity in the heart is crucial in understanding cardiac electrophysiology and devising new therapeutic solutions for control of cardiac arrhythmias. Current cardiac imaging techniques (i.e. optical mapping) employ voltage- or calcium-sensitive fluorescent dyes to visualize the electrical signal propagation through cardiac syncytium in vitro or in situ with very high-spatiotemporal resolution. The extension of optogenetics into the cardiac field, where cardiac tissue is genetically altered to express light-sensitive ion channels allowing electrical activity to be elicited or suppressed in a precise cell-specific way, has opened the possibility for all-optical interrogation of cardiac electrophysiology. In vivo application of cardiac optogenetics faces multiple challenges and necessitates suitable optical systems employing fiber optics to actuate and sense electrical signals. In this technical perspective, we present a compendium of clinically relevant access routes to different parts of the cardiac electrical conduction system based on currently employed catheter imaging systems and determine the quantitative size constraints for endoscopic cardiac optogenetics. We discuss the relevant technical advancements in microendoscopy, cardiac imaging, and optogenetics and outline the strategies for combining them to create a portable, miniaturized fiber-based system for all-optical interrogation of cardiac electrophysiology in vivo.
Active Interrogation using Photofission Technique for Nuclear Materials Control and Accountability
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Haori
2016-03-31
Innovative systems with increased sensitivity and resolution are in great demand to detect diversion and to prevent misuse in support of nuclear materials management for the U.S. fuel cycle. Nuclear fission is the most important multiplicative process involved in non-destructive active interrogation. This process produces the most easily recognizable signature for nuclear materials. In addition to thermal or high-energy neutrons, high-energy gamma rays can also excite a nucleus and cause fission through a process known as photofission. Electron linear accelerators (linacs) are widely used as the interrogating photon sources for inspection methods involving photofission technique. After photofission reactions, prompt signalsmore » are much stronger than the delayed signals, but it is difficult to quantify them in practical measurements. Delayed signals are easily distinguishable from the interrogating radiation. Linac-based, advanced inspection techniques utilizing the delayed signals after photofission have been extensively studied for homeland security applications. Previous research also showed that a unique delayed gamma ray energy spectrum exists for each fissionable isotope. In this work, high-energy delayed γ-rays were demonstrated to be signatures for detection, identification, and quantification of special nuclear materials. Such γ-rays were measured in between linac pulses using independent data acquisition systems. A list-mode system was developed to measure low-energy delayed γ-rays after irradiation. Photofission product yields of 238U and 239Pu were determined based on the measured delayed γ-ray spectra. The differential yields of delayed γ-rays were also proven to be able to discriminate nuclear from non-nuclear materials. The measurement outcomes were compared with Monte Carlo simulation results. It was demonstrated that the current available codes have capabilities and limitations in the simulation of photofission process. A two-fold approach was used to address the high-rate challenge in used nuclear fuel assay based on photofission technique. First, a standard HPGe preamplifier was modified to improve its capabilities in high-rate pulsed photofission environment. Second, advanced pulse processing algorithms were shown to greatly improve throughput rate without large sacrifice in energy resolution at ultra-high input count rate. Two customized gamma spectroscopy systems were also developed in real-time on FPGAs. They were shown to have promising performance matching available commercial units.« less
DOT National Transportation Integrated Search
2015-08-04
In 2012, the Navy requested spectrum certification for the shipboard AN/UPX-41(C) Digital Interrogator System, Software Version 5.5 with Mode 5. : Current operating conditions for the Navys AN/UPX-41(C) are the same as restrictions imposed on the ...
A Neutron Based Interrogation System For SNM In Cargo
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kane, Steven Z.; Koltick, David S.
A complete system has been simulated using experimentally obtained input parameters for the detection of special nuclear materials (SNM). A variation of the associated particle imaging (API) technique, referred to as reverse associated particle imaging detection (RAPID), has been developed in the context of detecting 5-kg spherical samples of U-235 in cargo. The RAPID technique allows for the interrogation of containers at neutron production rates between {approx}1x10{sup 8} neutrons/s and {approx}3x10{sup 8} neutrons/s. The merit of performance for the system is the time to detect the threat material with 95% probability of detection and 10{sup -4} false positive rate permore » interrogated voxel of cargo. Detection times of 5 minutes were found for a maximally loaded cargo container uniformly filled with iron and as low as 1 second in containers loaded to 1/4 of full capacity with either iron or wood. The worse case system performance, 30 minutes interrogation time, occurs for a maximally loaded container containing wood at 0.4 g/cm{sup 3}.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rodriguez, George; Gilbertson, Steve Michael
Chirped fiber Bragg grating (CFBG) sensors coupled to high speed interrogation systems are described as robust diagnostic approaches to monitoring shock wave and detonation front propagation tracking events for use in high energy density shock physics applications. Taking advantage of the linear distributed spatial encoding of the spectral band in single-mode CFBGs, embedded fiber systems and associated photonic interrogation methodologies are shown as an effective approach to sensing shock and detonation-driven loading processes along the CFBG length. Two approaches, one that detects spectral changes in the integrated spectrum of the CFBG and another coherent pulse interrogation approach that fully resolvesmore » its spectral response, shows that 100-MHz–1-GHz interrogation rates are possible with spatial resolution along the CFBG in the 50 µm to sub-millimeter range depending on the combination of CFBG parameters (i.e., length, chirp rate, spectrum) and interrogator design specifics. In conclusion, results from several dynamic tests are used to demonstrate the performance of these high speed systems for shock and detonation propagation tracking under strong and weak shock pressure loading: (1) linear detonation front tracking in the plastic bonded explosive (PBX) PBX-9501; (2) tracking of radial decaying shock with crossover to non-destructive CFBG response; (3) shock wave tracking along an aluminum cylinder wall under weak loading accompanied by dynamic strain effects in the CFBG sensor.« less
Connolly, Patrick J.; Wolf, Keith; O'Neal, Jennifer S.
2010-01-01
With increasing use of passive integrated transponder (PIT) tags and reliance on stationary PIT tag interrogation systems to monitor fish populations, guidelines are offered to inform users how best to use limited funding and human resources to create functional systems that maximize a desired level of detection and precision. The estimators of detection efficiency and their variability as described by Connolly et al. (2008) are explored over a span of likely performance metrics. These estimators were developed to estimate detection efficiency without relying on a known number of fish passing the system. I present graphical displays of the results derived from these estimators to show the potential efficiency and precision to be gained by adding an array or by increasing the number of PIT-tagged fish expected to move past an interrogation system.
Guidelines for calculating and enhancing detection efficiency of PIT tag interrogation systems
Connolly, Patrick J.
2010-01-01
With increasing use of passive integrated transponder (PIT) tags and reliance on stationary PIT tag interrogation systems to monitor fish populations, guidelines are offered to inform users how best to use limited funding and human resources to create functional systems that maximize a desired level of detection and precision. The estimators of detection efficiency and their variability as described by Connolly et al. (2008) are explored over a span of likely performance metrics. These estimators were developed to estimate detection efficiency without relying on a known number of fish passing the system. I present graphical displays of the results derived from these estimators to show the potential efficiency and precision to be gained by adding an array or by increasing the number of PIT-tagged fish expected to move past an interrogation system.
A fiber-Bragg-grating sensor interrogation system using in-fiber Fabry-Pérot interferometer
NASA Astrophysics Data System (ADS)
Wang, Ting-ting; Wang, Ming
2011-11-01
A fiber-Bragg-grating sensor interrogation system using a in-fiber Fabry-Pérot interferometer (IFFPI) is presented. The IFFPI was formed by splicing together a conventional single-mode fiber and a photonic crystal fiber with simple arcdischarge technique. The ellipsoidal air-cavity between the two fibers forms Fabry-Pérot cavity. The diffraction loss can be very low due to the focusing of reentrant and very short cavity length, thus resulting in high visibility and long period. The IFFPI is used as the filter component of the interrogation system. The resolving wavelength can achieve 2pm by using an Er-doped ring FBG laser in the experimental system. The advantages of this system are an all-fiber design, temperature insensitivity, quasistatic and dynamic operation, potential high speed and large range demodulation.
Interrogation of an object for dimensional and topographical information
McMakin, Douglas L.; Severtsen, Ronald H.; Hall, Thomas E.; Sheen, David M.; Kennedy, Mike O.
2004-03-09
Disclosed are systems, methods, devices, and apparatus to interrogate a clothed individual with electromagnetic radiation to determine one or more body measurements at least partially covered by the individual's clothing. The invention further includes techniques to interrogate an object with electromagnetic radiation in the millimeter and/or microwave range to provide a volumetric representation of the object. This representation can be used to display images and/or determine dimensional information concerning the object.
Interrogation of an object for dimensional and topographical information
McMakin, Doug L [Richland, WA; Severtsen, Ronald H [Richland, WA; Hall, Thomas E [Richland, WA; Sheen, David M [Richland, WA
2003-01-14
Disclosed are systems, methods, devices, and apparatus to interrogate a clothed individual with electromagnetic radiation to determine one or more body measurements at least partially covered by the individual's clothing. The invention further includes techniques to interrogate an object with electromagnetic radiation in the millimeter and/or microwave range to provide a volumetric representation of the object. This representation can be used to display images and/or determine dimensional information concerning the object.
Abraham, Sara A; Kearfott, Kimberlee J; Jawad, Ali H; Boria, Andrew J; Buth, Tobias J; Dawson, Alexander S; Eng, Sheldon C; Frank, Samuel J; Green, Crystal A; Jacobs, Mitchell L; Liu, Kevin; Miklos, Joseph A; Nguyen, Hien; Rafique, Muhammad; Rucinski, Blake D; Smith, Travis; Tan, Yanliang
2017-03-01
Optically-stimulated luminescent dosimeters are capable of being interrogated multiple times post-irradiation. Each interrogation removes a fraction of the signal stored within the optically-stimulated luminescent dosimeter. This signal loss must be corrected to avoid systematic errors in estimating the average signal of a series of optically-stimulated luminescent dosimeter interrogations and requires a minimum number of consecutive readings to determine an average signal that is within a desired accuracy of the true signal with a desired statistical confidence. This paper establishes a technical basis for determining the required number of readings for a particular application of these dosimeters when using certain OSL dosimetry systems.
Coded acoustic wave sensors and system using time diversity
NASA Technical Reports Server (NTRS)
Solie, Leland P. (Inventor); Hines, Jacqueline H. (Inventor)
2012-01-01
An apparatus and method for distinguishing between sensors that are to be wirelessly detected is provided. An interrogator device uses different, distinct time delays in the sensing signals when interrogating the sensors. The sensors are provided with different distinct pedestal delays. Sensors that have the same pedestal delay as the delay selected by the interrogator are detected by the interrogator whereas other sensors with different pedestal delays are not sensed. Multiple sensors with a given pedestal delay are provided with different codes so as to be distinguished from one another by the interrogator. The interrogator uses a signal that is transmitted to the sensor and returned by the sensor for combination and integration with the reference signal that has been processed by a function. The sensor may be a surface acoustic wave device having a differential impulse response with a power spectral density consisting of lobes. The power spectral density of the differential response is used to determine the value of the sensed parameter or parameters.
Systems and Methods for RFID-Enabled Pressure Sensing Apparatus
NASA Technical Reports Server (NTRS)
Kennedy, Timothy F. (Inventor); Lin, Gregory Y. (Inventor); Ngo, Phong H. (Inventor); Fink, Patrick W. (Inventor)
2017-01-01
Methods, apparatuses and systems for radio frequency identification (RFID)-enabled information collection are disclosed, including an enclosure, a collector coupled to the enclosure, an interrogator, a processor, and one or more RFID field sensors, each having an individual identification, disposed within the enclosure. In operation, the interrogator transmits an incident signal to the collector, causing the collector to generate an electromagnetic field within the enclosure. The electromagnetic field is affected by one or more influences. RFID sensors respond to the electromagnetic field by transmitting reflected signals containing the individual identifications of the responding RFID sensors to the interrogator. The interrogator receives the reflected signals, measures one or more returned signal strength indications ("RSSI") of the reflected signals and sends the RSSI measurements and identification of the responding RFID sensors to the processor to determine one or more facts about the influences. Other embodiments are also described.
Systems and Methods for RFID-Enabled Dispenser
NASA Technical Reports Server (NTRS)
Fink, Patrick W. (Inventor); Kennedy, Timothy F. (Inventor); Lin, Gregory Y. (Inventor); Ngo, Phong H. (Inventor); Byerly, Diane (Inventor)
2015-01-01
Methods, apparatuses and systems for radio frequency identification (RFID)-enabled information collection are disclosed, including an enclosure, a collector coupled to the enclosure, an interrogator, a processor, and one or more RFID field sensors, each having an individual identification, disposed within the enclosure. In operation, the interrogator transmits an incident signal to the collector, causing the collector to generate an electromagnetic field within the enclosure. The electromagnetic field is affected by one or more influences. RFID sensors respond to the electromagnetic field by transmitting reflected signals containing the individual identifications of the responding RFID sensors to the interrogator. The interrogator receives the reflected signals, measures one or more returned signal strength indications ("RSSI") of the reflected signals and sends the RSSI measurements and identification of the responding RFID sensors to the processor to determine one or more facts about the influences. Other embodiments are also described.
Systems and Methods for RFID-Enabled Pressure Sensing Apparatus
NASA Technical Reports Server (NTRS)
Lin, Gregory Y. (Inventor); Ngo, Phong H. (Inventor); Kennedy, Timothy F. (Inventor); Fink, Patrick W. (Inventor)
2016-01-01
Methods, apparatuses and systems for radio frequency identification (RFID)-enabled information collection are disclosed, including an enclosure, a collector coupled to the enclosure, an interrogator, a processor, and one or more RFID field sensors, each having an individual identification, disposed within the enclosure. In operation, the interrogator transmits an incident signal to the collector, causing the collector to generate an electromagnetic field within the enclosure. The electromagnetic field is affected by one or more influences. RFID sensors respond to the electromagnetic field by transmitting reflected signals containing the individual identifications of the responding RFID sensors to the interrogator. The interrogator receives the reflected signals, measures one or more returned signal strength indications ("RSSI") of the reflected signals and sends the RSSI measurements and identification of the responding RFID sensors to the processor to determine one or more facts about the influences. Other embodiments are also described.
System and Method for RFID-Enabled Information Collection
NASA Technical Reports Server (NTRS)
Fink, Patrick W. (Inventor); Kennedy, Timothy F. (Inventor); Lin, Gregory Y. (Inventor); Ngo, Phong H. (Inventor); Byerly, Diane (Inventor)
2016-01-01
Methods, apparatuses and systems for radio frequency identification (RFID)-enabled information collection are disclosed, including an enclosure, a collector coupled to the enclosure, an interrogator, a processor, and one or more RFID field sensors, each having an individual identification, disposed within the enclosure. In operation, the interrogator transmits an incident signal to the collector, causing the collector to generate an electromagnetic field within the enclosure. The electromagnetic field is affected by one or more influences. RFID sensors respond to the electromagnetic field by transmitting reflected signals containing the individual identifications of the responding RFID sensors to the interrogator. The interrogator receives the reflected signals, measures one or more returned signal strength indications ("RSSI") of the reflected signals and sends the RSSI measurements and identification of the responding RFID sensors to the processor to determine one or more facts about the influences. Other embodiments are also described.
Neutron Interrogation System For Underwater Threat Detection And Identification
NASA Astrophysics Data System (ADS)
Barzilov, Alexander P.; Novikov, Ivan S.; Womble, Phil C.
2009-03-01
Wartime and terrorist activities, training and munitions testing, dumping and accidents have generated significant munitions contamination in the coastal and inland waters in the United States and abroad. Although current methods provide information about the existence of the anomaly (for instance, metal objects) in the sea bottom, they fail to identify the nature of the found objects. Field experience indicates that often in excess of 90% of objects excavated during the course of munitions clean up are found to be non-hazardous items (false alarm). The technology to detect and identify waterborne or underwater threats is also vital for protection of critical infrastructures (ports, dams, locks, refineries, and LNG/LPG). We are proposing a compact neutron interrogation system, which will be used to confirm possible threats by determining the chemical composition of the suspicious underwater object. The system consists of an electronic d-T 14-MeV neutron generator, a gamma detector to detect the gamma signal from the irradiated object and a data acquisition system. The detected signal then is analyzed to quantify the chemical elements of interest and to identify explosives or chemical warfare agents.
NASA Technical Reports Server (NTRS)
1971-01-01
Nimbus 4 satellite data for the period September 1 through October 31 1970 are presented. Data are also given on interrogation recording and location system balloon tracking from launch through March 27, 1971.
An Evaluation of "Miranda" Rights and Interrogation in Autism Spectrum Disorders
ERIC Educational Resources Information Center
Salseda, Lindsay M.; Dixon, Dennis R.; Fass, Tracy; Miora, Deborah; Leark, Robert A.
2011-01-01
The primary deficits present in autism spectrum disorders (ASD) may lead to increased susceptibility to involvement in the criminal justice system. The same deficits may also cause individuals with ASD to be more vulnerable to interrogation techniques and other aspects of the legal system. Due to the increased level of vulnerability as well as…
Low-Cost Interrogation Technique for Dynamic Measurements with FBG-Based Devices.
Díaz, Camilo A R; Leitão, Cátia; Marques, Carlos A; Domingues, M Fátima; Alberto, Nélia; Pontes, Maria José; Frizera, Anselmo; Ribeiro, Moisés R N; André, Paulo S B; Antunes, Paulo F C
2017-10-23
Fiber Bragg gratings are widely used optical fiber sensors for measuring temperature and/or mechanical strain. Nevertheless, the high cost of the interrogation systems is the most important drawback for their large commercial application. In this work, an in-line Fabry-Perot interferometer based edge filter is explored in the interrogation of fiber Bragg grating dynamic measurements up to 5 kHz. Two devices an accelerometer and an arterial pulse wave probe were interrogated with the developed approach and the results were compared with a commercial interrogation monitor. The data obtained with the edge filter are in agreement with the commercial device, with a maximum RMSE of 0.05 being able to meet the requirements of the measurements. Resolutions of 3.6 pm and 2.4 pm were obtained, using the optical accelerometer and the arterial pulse wave probe, respectively.
NASA Astrophysics Data System (ADS)
Martin, Philip N.; Clemett, Ceri D.; Hill, Cassie; O'Malley, John; Campbell, Ben
This paper describes and compares two approaches to the analysis of active interrogation data containing high photon backgrounds associated with mixed photon-neutron source flash active interrogation. Results from liquid scintillation detectors (EJ301/EJ309) fielded at the Naval Research Laboratory (NRL), in collaboration with the Atomic Weapons Establishment (AWE), using the NRL Mercury Inductive Voltage Adder (IVA) operating in both a photon and mixed photon-neutron mode at a Depleted Uranium (DU) target are presented. The standard approach applying a Figure of Merit (FOM) consisting of background sigma above background is compared with an approach looking to fit only the time-decaying photon signal with standard delayed photon emission from ∼10-MeV end-point-energy Bremsstrahlung photofission of DU. Examples where each approach does well and less well are presented together with a discussion of the relative limitations of both approaches to the type of mixed photon-neutron flash active interrogation being considered.
NASA Astrophysics Data System (ADS)
Misawa, Tsuyoshi; Takahashi, Yoshiyuki; Yagi, Takahiro; Pyeon, Cheol Ho; Kimura, Masaharu; Masuda, Kai; Ohgaki, Hideaki
2015-10-01
For detection of hidden special nuclear materials (SNMs), we have developed an active neutron-based interrogation system combined with a D-D fusion pulsed neutron source and a neutron detection system. In the detection scheme, we have adopted new measurement techniques simultaneously; neutron noise analysis and neutron energy spectrum analysis. The validity of neutron noise analysis method has been experimentally studied in the Kyoto University Critical Assembly (KUCA), and was applied to a cargo container inspection system by simulation.
Optically powered and interrogated rotary position sensor for aircraft engine control applications
NASA Astrophysics Data System (ADS)
Spillman, W. B.; Crowne, D. H.; Woodward, D. W.
A throttle level angle (TLA) sensing system is described that utilizes a capacitance based rotary position transducer that is powered and interrogated via light from a single multimode optical fiber. The system incorporates a unique GaAs device that serves as both a power converter and optical data transmitter. Design considerations are discussed, and the fabrication and performance of the sensor system are detailed.
Automatic translation among spoken languages
NASA Technical Reports Server (NTRS)
Walter, Sharon M.; Costigan, Kelly
1994-01-01
The Machine Aided Voice Translation (MAVT) system was developed in response to the shortage of experienced military field interrogators with both foreign language proficiency and interrogation skills. Combining speech recognition, machine translation, and speech generation technologies, the MAVT accepts an interrogator's spoken English question and translates it into spoken Spanish. The spoken Spanish response of the potential informant can then be translated into spoken English. Potential military and civilian applications for automatic spoken language translation technology are discussed in this paper.
Tunable-optical-filter-based white-light interferometry for sensing.
Yu, Bing; Wang, Anbo; Pickrell, Gary; Xu, Juncheng
2005-06-15
We describe tunable-optical-filter-based white-light interferometry for sensor interrogation. By introducing a tunable optical filter into a white-light interferometry system, one can interrogate an interferometer with either quadrature demodulation or spectral-domain detection at low cost. To demonstrate the feasibility of effectively demodulating various types of interferometric sensor, experiments have been performed using an extrinsic Fabry-Perot tunable filter to interrogate two extrinsic Fabry-Perot interferometric temperature sensors and a diaphragm-based pressure sensor.
Method of remote powering and detecting multiple UWB passive tags in an RFID system
Dowla, Farid U [Castro Valley, CA; Nekoogar, Faranak [San Ramon, CA; Benzel, David M [Livermore, CA; Dallum, Gregory E [Livermore, CA; Spiridon, Alex [Palo Alto, CA
2012-05-29
A new Radio Frequency Identification (RFID), tracking, powering apparatus/system and method using coded Ultra-wideband (UWB) signaling is introduced. The proposed hardware and techniques disclosed herein utilize a plurality of passive UWB transponders in a field of an RFID-radar system. The radar system itself enables multiple passive tags to be remotely powered (activated) at about the same time frame via predetermined frequency UWB pulsed formats. Once such tags are in an activated state, an UWB radar transmits specific "interrogating codes" to put predetermined tags in an awakened status. Such predetermined tags can then communicate by a unique "response code" so as to be detected by an UWB system using radar methods.
Li, Sinan; Lin, Shengtao; Cheng, Yi; Matsunaga, Terry O; Eckersley, Robert J; Tang, Meng-Xing
2015-05-01
Phase-change contrast agents in the form of nanoscale droplets can be activated into microbubbles by ultrasound, extending the contrast beyond the vasculature. This article describes simultaneous optical and acoustical measurements for quantifying the ultrasound activation of phase-change contrast agents over a range of concentrations. In experiments, decafluorobutane-based nanodroplets of different dilutions were sonicated with a high-pressure activation pulse and two low-pressure interrogation pulses immediately before and after the activation pulse. The differences between the pre- and post-interrogation signals were calculated to quantify the acoustic power scattered by the microbubbles activated over a range of droplet concentrations. Optical observation occurred simultaneously with the acoustic measurement, and the pre- and post-microscopy images were processed to generate an independent quantitative indicator of the activated microbubble concentration. Both optical and acoustic measurements revealed linear relationships to the droplet concentration at a low concentration range <10(8)/mL when measured at body temperature. Further increases in droplet concentration resulted in saturation of the acoustic interrogation signal. Compared with body temperature, room temperature was found to produce much fewer and larger bubbles after ultrasound droplet activation. Copyright © 2015. Published by Elsevier Inc.
A knowledge based application of the extended aircraft interrogation and display system
NASA Technical Reports Server (NTRS)
Glover, Richard D.; Larson, Richard R.
1991-01-01
A family of multiple-processor ground support test equipment was used to test digital flight-control systems on high-performance research aircraft. A unit recently built for the F-18 high alpha research vehicle project is the latest model in a series called the extended aircraft interrogation and display system. The primary feature emphasized monitors the aircraft MIL-STD-1553B data buses and provides real-time engineering units displays of flight-control parameters. A customized software package was developed to provide real-time data interpretation based on rules embodied in a highly structured knowledge database. The configuration of this extended aircraft interrogation and display system is briefly described, and the evolution of the rule based package and its application to failure modes and effects testing on the F-18 high alpha research vehicle is discussed.
Design of a fiber-optic interrogator module for telecommunication satellites
NASA Astrophysics Data System (ADS)
Putzer, Philipp; Koch, Alexander W.; Plattner, Markus; Hurni, Andreas; Manhart, Markus
2017-11-01
In this paper we present the results of the radiation tests performed on the optical components of the fiber-optic interrogator module as a part of the Hybrid Sensor Bus (HSB) system. The HSB-system is developed in the frame of an ESAARTES program and will be verified as flight demonstrator onboard the German Heinrich Hertz satellite in 2016. The HSB system is based on a modular concept which includes sensor interrogation modules based on I2C electrical and fiber Bragg grating (FBG) fiber-optical sensor elements. Onboard fiber-optic sensing allows the implementation of novel control and monitoring methods. For read-out of multiple FBG sensors, a design based on a tunable laser diode as well as a design based on a spectrometer is considered. The expected and tested total ionizing dose (TID) applicable to the HSB system is in the range between 100 krad and 300 krad inside the satellite in the geostationary orbit over a life time of 15 years. We present radiation test results carried out on critical optical components to be used in the fiber-optic interrogation module. These components are a modulated grating Y-branch (MGY) tunable laser diode acting as light source for the tuning laser approach, the line detector of a spectrometer, photodetectors and the FBG sensors acting as sensor elements. A detailed literature inquiry of radiation effects on optical fibers and FBG sensors, is also included in the paper. The fiber-optic interrogator module implemented in the HSB system is based on the most suitable technology, which sustains the harsh environment in the geostationary orbit.
Hand Held Device for Wireless Powering and Interrogation of Biomems Sensors and Actuators
NASA Technical Reports Server (NTRS)
Simons, Rainee N (Inventor); Miranda, Felix Antonio (Inventor)
2007-01-01
A compact, hand-held device for wireless powering, interrogation and data retrieval from at least one implanted sensor. The hand-held device includes an antenna for powering an implanted sensor and for receiving data from the implanted sensor to the hand-held device for at least one of storage, display or analysis. The hand-held device establishes electromagnetic coupling with a low radiating radio frequency power inductor in the implanted sensor at a predefined separation and the antenna geometry allows for the antenna to power, interrogate and retrieve data from the implanted sensor without strapping the hand-held device to a human body housing the implanted sensor The hand-held device optionally allows for activation of the implanted sensor only during interrogation and data retrieval.
Programed asynchronous serial data interrogation in a two-computer system
NASA Technical Reports Server (NTRS)
Schneberger, N. A.
1975-01-01
Technique permits redundant computers, with one unit in control mode and one in MONITOR mode, to interrogate the same serial data source. Its use for program-controlled serial data transfer results in extremely simple hardware and software mechanization.
Wavelength interrogation of fiber Bragg grating sensors using tapered hollow Bragg waveguides.
Potts, C; Allen, T W; Azar, A; Melnyk, A; Dennison, C R; DeCorby, R G
2014-10-15
We describe an integrated system for wavelength interrogation, which uses tapered hollow Bragg waveguides coupled to an image sensor. Spectral shifts are extracted from the wavelength dependence of the light radiated at mode cutoff. Wavelength shifts as small as ~10 pm were resolved by employing a simple peak detection algorithm. Si/SiO₂-based cladding mirrors enable a potential operational range of several hundred nanometers in the 1550 nm wavelength region for a taper length of ~1 mm. Interrogation of a strain-tuned grating was accomplished using a broadband amplified spontaneous emission (ASE) source, and potential for single-chip interrogation of multiplexed sensor arrays is demonstrated.
High performance multi-spectral interrogation for surface plasmon resonance imaging sensors.
Sereda, A; Moreau, J; Canva, M; Maillart, E
2014-04-15
Surface plasmon resonance (SPR) sensing has proven to be a valuable tool in the field of surface interactions characterization, especially for biomedical applications where label-free techniques are of particular interest. In order to approach the theoretical resolution limit, most SPR-based systems have turned to either angular or spectral interrogation modes, which both offer very accurate real-time measurements, but at the expense of the 2-dimensional imaging capability, therefore decreasing the data throughput. In this article, we show numerically and experimentally how to combine the multi-spectral interrogation technique with 2D-imaging, while finding an optimum in terms of resolution, accuracy, acquisition speed and reduction in data dispersion with respect to the classical reflectivity interrogation mode. This multi-spectral interrogation methodology is based on a robust five parameter fitting of the spectral reflectivity curve which enables monitoring of the reflectivity spectral shift with a resolution of the order of ten picometers, and using only five wavelength measurements per point. In fine, such multi-spectral based plasmonic imaging system allows biomolecular interaction monitoring in a linear regime independently of variations of buffer optical index, which is illustrated on a DNA-DNA model case. © 2013 Elsevier B.V. All rights reserved.
Stedmon, Alex W; Eachus, Peter; Baillie, Les; Tallis, Huw; Donkor, Richard; Edlin-White, Robert; Bracewell, Robert
2015-03-01
Individuals trying to conceal knowledge from interrogators are likely to experience raised levels of stress that can manifest itself across biological, physiological, psychological and behavioural factors, providing an opportunity for detection. Using established research paradigms an innovative scalable interrogation was designed in which participants were given a 'token' that represented information they had to conceal from interviewers. A control group did not receive a token and therefore did not have to deceive the investigators. The aim of this investigation was to examine differences between deceivers and truth-tellers across the four factors by collecting data for cortisol levels, sweat samples, heart-rate, respiration, skin temperature, subjective stress ratings and video and audio recordings. The results provided an integrated understanding of responses to interrogation by those actively concealing information and those acting innocently. Of particular importance, the results also suggest, for the first time in an interrogation setting, that stressed individuals may secrete a volatile steroid based marker that could be used for stand-off detection. The findings are discussed in relation to developing a scalable interrogation protocol for future research in this area. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Low-Cost Interrogation Technique for Dynamic Measurements with FBG-Based Devices
Domingues, M. Fátima; Alberto, Nélia; Pontes, Maria José; Ribeiro, Moisés R. N.; André, Paulo S. B.; Antunes, Paulo F. C.
2017-01-01
Fiber Bragg gratings are widely used optical fiber sensors for measuring temperature and/or mechanical strain. Nevertheless, the high cost of the interrogation systems is the most important drawback for their large commercial application. In this work, an in-line Fabry–Perot interferometer based edge filter is explored in the interrogation of fiber Bragg grating dynamic measurements up to 5 kHz. Two devices an accelerometer and an arterial pulse wave probe were interrogated with the developed approach and the results were compared with a commercial interrogation monitor. The data obtained with the edge filter are in agreement with the commercial device, with a maximum RMSE of 0.05 being able to meet the requirements of the measurements. Resolutions of 3.6 pm and 2.4 pm were obtained, using the optical accelerometer and the arterial pulse wave probe, respectively. PMID:29065518
Explosives (and other threats) detection using pulsed neutron interrogation and optimized detectors
NASA Astrophysics Data System (ADS)
Strellis, Dan A.; Elsalim, Mashal; Gozani, Tsahi
2011-06-01
We have previously reported results from a human-portable system using neutron interrogation to detect contraband and explosives. We summarized our methodology for distinguishing threat materials such as narcotics, C4, and mustard gas in the myriad of backgrounds present in the maritime environment. We are expanding our mission for the Domestic Nuclear Detection Office (DNDO) to detect Special Nuclear Material (SNM) through the detection of multiple fission signatures without compromising the conventional threat detection performance. This paper covers our initial investigations into using neutrons from compact pulsed neutron generators via the d(D,n)3He or d(T,n)α reactions with energies of ~2.5 and 14 MeV, respectively, for explosives (and other threats) detection along with a variety of gamma-ray detectors. Fast neutrons and thermal neutrons (after successive collisions) can stimulate the emission of various threat detection signatures. For explosives detection, element-specific gamma-ray signatures via the (n,n'γ) inelastic scattering reaction and the (n,'γ) thermal capture reaction are detected. For SNM, delayed gamma-rays following fission can be measured with the same detector. Our initial trade-off investigations of several gamma-ray detectors types (NaI, CsI, LaBr3, HPGe) for measuring gamma-ray signatures in a pulsed neutron environment for potential application in a human-portable active interrogation system are covered in this paper.
Characterization of FBG sensor interrogation based on a FDML wavelength swept laser
Jung, Eun Joo; Kim, Chang-Seok; Jeong, Myung Yung; Kim, Moon Ki; Jeon, Min Yong; Jung, Woonggyu; Chen, Zhongping
2012-01-01
In this study, we develop an ultra-fast fiber Bragg grating sensor system that is based on the Fourier domain mode-locked (FDML) swept laser. A FDML wavelength swept laser has many advantages compared to the conventional wavelength swept laser source, such as high-speed interrogation, narrow spectral sensitivity, and high phase stability. The newly developed FDML wavelength swept laser shows a superior performance of a high scan rate of 31.3 kHz and a broad scan range of over 70 nm simultaneously. The performance of the grating sensor interrogating system using a FDML wavelength swept laser is characterized in both static and dynamic strain responses. PMID:18852764
Carrender, Curtis Lee; Gilbert, Ronald W.
2007-02-20
A radio frequency (RF) communication system employs phase-modulated backscatter signals for RF communication from an RF tag to an interrogator. The interrogator transmits a continuous wave interrogation signal to the RF tag, which based on an information code stored in a memory, phase-modulates the interrogation signal to produce a backscatter response signal that is transmitted back to the interrogator. A phase modulator structure in the RF tag may include a switch coupled between an antenna and a quarter-wavelength stub; and a driver coupled between the memory and a control terminal of the switch. The driver is structured to produce a modulating signal corresponding to the information code, the modulating signal alternately opening and closing the switch to respectively decrease and increase the transmission path taken by the interrogation signal and thereby modulate the phase of the response signal. Alternatively, the phase modulator may include a diode coupled between the antenna and driver. The modulating signal from the driver modulates the capacitance of the diode, which modulates the phase of the response signal reflected by the diode and antenna.
Optogenetic interrogation of neural circuits: technology for probing mammalian brain structures
Zhang, Feng; Gradinaru, Viviana; Adamantidis, Antoine R; Durand, Remy; Airan, Raag D; de Lecea, Luis; Deisseroth, Karl
2015-01-01
Elucidation of the neural substrates underlying complex animal behaviors depends on precise activity control tools, as well as compatible readout methods. Recent developments in optogenetics have addressed this need, opening up new possibilities for systems neuroscience. Interrogation of even deep neural circuits can be conducted by directly probing the necessity and sufficiency of defined circuit elements with millisecond-scale, cell type-specific optical perturbations, coupled with suitable readouts such as electrophysiology, optical circuit dynamics measures and freely moving behavior in mammals. Here we collect in detail our strategies for delivering microbial opsin genes to deep mammalian brain structures in vivo, along with protocols for integrating the resulting optical control with compatible readouts (electrophysiological, optical and behavioral). The procedures described here, from initial virus preparation to systems-level functional readout, can be completed within 4–5 weeks. Together, these methods may help in providing circuit-level insight into the dynamics underlying complex mammalian behaviors in health and disease. PMID:20203662
Noncontact power/interrogation system for smart structures
NASA Astrophysics Data System (ADS)
Spillman, William B., Jr.; Durkee, S.
1994-05-01
The field of smart structures has been largely driven by the development of new high performance designed materials. Use of these materials has been generally limited due to the fact that they have not been in use long enough for statistical data bases to be developed on their failure modes. Real time health monitoring is therefore required for the benefits of structures using these materials to be realized. In this paper a non-contact method of powering and interrogating embedded electronic and opto-electronic systems is described. The technique utilizes inductive coupling between external and embedded coils etched on thin electronic circuit cards. The technique can be utilized to interrogate embedded sensors and to provide > 250 mW for embedded electronics. The system has been successfully demonstrated with a number of composite and plastic materials through material thicknesses up to 1 cm. An analytical description of the system is provided along with experimental results.
Ultra Small Integrated Optical Fiber Sensing System
Van Hoe, Bram; Lee, Graham; Bosman, Erwin; Missinne, Jeroen; Kalathimekkad, Sandeep; Maskery, Oliver; Webb, David J.; Sugden, Kate; Van Daele, Peter; Van Steenberge, Geert
2012-01-01
This paper introduces a revolutionary way to interrogate optical fiber sensors based on fiber Bragg gratings (FBGs) and to integrate the necessary driving optoelectronic components with the sensor elements. Low-cost optoelectronic chips are used to interrogate the optical fibers, creating a portable dynamic sensing system as an alternative for the traditionally bulky and expensive fiber sensor interrogation units. The possibility to embed these laser and detector chips is demonstrated resulting in an ultra thin flexible optoelectronic package of only 40 μm, provided with an integrated planar fiber pigtail. The result is a fully embedded flexible sensing system with a thickness of only 1 mm, based on a single Vertical-Cavity Surface-Emitting Laser (VCSEL), fiber sensor and photodetector chip. Temperature, strain and electrodynamic shaking tests have been performed on our system, not limited to static read-out measurements but dynamically reconstructing full spectral information datasets.
Individually Identifiable Surface Acoustic Wave Sensors, Tags and Systems
NASA Technical Reports Server (NTRS)
Hines, Jacqueline H. (Inventor); Solie, Leland P. (Inventor); Tucker, Dana Y. G. (Inventor); Hines, Andrew T. (Inventor)
2017-01-01
A surface-launched acoustic wave sensor tag system for remotely sensing and/or providing identification information using sets of surface acoustic wave (SAW) sensor tag devices is characterized by acoustic wave device embodiments that include coding and other diversity techniques to produce groups of sensors that interact minimally, reducing or alleviating code collision problems typical of prior art coded SAW sensors and tags, and specific device embodiments of said coded SAW sensor tags and systems. These sensor/tag devices operate in a system which consists of one or more uniquely identifiable sensor/tag devices and a wireless interrogator. The sensor device incorporates an antenna for receiving incident RF energy and re-radiating the tag identification information and the sensor measured parameter(s). Since there is no power source in or connected to the sensor, it is a passive sensor. The device is wirelessly interrogated by the interrogator.
NASA Astrophysics Data System (ADS)
Alfonso, Krystal; Elsalim, Mashal; King, Michael; Strellis, Dan; Gozani, Tsahi
2013-04-01
MCNPX simulations have been used to guide the development of a portable inspection system for narcotics, explosives, and special nuclear material (SNM) detection. The system seeks to address these threats to national security by utilizing a high-yield, compact neutron source to actively interrogate the threats and produce characteristic signatures that can then be detected by radiation detectors. The portability of the system enables rapid deployment and proximity to threats concealed in small spaces. Both dD and dT electronic neutron generators (ENG) were used to interrogate ammonium nitrate fuel oil (ANFO) and cocaine hydrochloride, and the detector response of NaI, CsI, and LaBr3 were compared. The effect of tungsten shielding on the neutron flux in the gamma ray detectors was investigated, while carbon, beryllium, and polyethylene ENG moderator materials were optimized by determining the reaction rate density in the threats. In order to benchmark the modeling results, experimental measurements are compared with MCNPX simulations. In addition, the efficiency and die-away time of a portable differential die-away analysis (DDAA) detector using 3He proportional counters for SNM detection has been determined.
NASA Astrophysics Data System (ADS)
Chandler, K.; Ferguson, S.; Graver, T.; Csipkes, A.; Mendez, A.
2008-03-01
We report in this paper on the design and development of a novel on-line structural health monitoring and fire detection system based on an array of optical fiber Bragg grating (FBG) sensors and interrogation system installed on a new, precommercial compact aircraft. A combined total of 17 FBG sensors - strain, temperature and high-temperature - were installed at critical locations in an around the wings, fuselage and engine compartment of a prototype, Comp Air CA 12 all-composite, ten-passenger personal airplane powered by a 1,650 hp turbine engine. The sensors are interrogated online and in real time by a swept laser FBG interrogator (Micron Optics sm125-700) mounted on board the plane. Sensors readings are then combined with the plane's avionics system and displayed on the pilot's aviation control panel. This system represents the first of its kind in commercial, small frame, airplanes and a first for optical fiber sensors.
A Fiber Bragg Grating Interrogation System with Self-Adaption Threshold Peak Detection Algorithm.
Zhang, Weifang; Li, Yingwu; Jin, Bo; Ren, Feifei; Wang, Hongxun; Dai, Wei
2018-04-08
A Fiber Bragg Grating (FBG) interrogation system with a self-adaption threshold peak detection algorithm is proposed and experimentally demonstrated in this study. This system is composed of a field programmable gate array (FPGA) and advanced RISC machine (ARM) platform, tunable Fabry-Perot (F-P) filter and optical switch. To improve system resolution, the F-P filter was employed. As this filter is non-linear, this causes the shifting of central wavelengths with the deviation compensated by the parts of the circuit. Time-division multiplexing (TDM) of FBG sensors is achieved by an optical switch, with the system able to realize the combination of 256 FBG sensors. The wavelength scanning speed of 800 Hz can be achieved by a FPGA+ARM platform. In addition, a peak detection algorithm based on a self-adaption threshold is designed and the peak recognition rate is 100%. Experiments with different temperatures were conducted to demonstrate the effectiveness of the system. Four FBG sensors were examined in the thermal chamber without stress. When the temperature changed from 0 °C to 100 °C, the degree of linearity between central wavelengths and temperature was about 0.999 with the temperature sensitivity being 10 pm/°C. The static interrogation precision was able to reach 0.5 pm. Through the comparison of different peak detection algorithms and interrogation approaches, the system was verified to have an optimum comprehensive performance in terms of precision, capacity and speed.
A Fiber Bragg Grating Interrogation System with Self-Adaption Threshold Peak Detection Algorithm
Zhang, Weifang; Li, Yingwu; Jin, Bo; Ren, Feifei
2018-01-01
A Fiber Bragg Grating (FBG) interrogation system with a self-adaption threshold peak detection algorithm is proposed and experimentally demonstrated in this study. This system is composed of a field programmable gate array (FPGA) and advanced RISC machine (ARM) platform, tunable Fabry–Perot (F–P) filter and optical switch. To improve system resolution, the F–P filter was employed. As this filter is non-linear, this causes the shifting of central wavelengths with the deviation compensated by the parts of the circuit. Time-division multiplexing (TDM) of FBG sensors is achieved by an optical switch, with the system able to realize the combination of 256 FBG sensors. The wavelength scanning speed of 800 Hz can be achieved by a FPGA+ARM platform. In addition, a peak detection algorithm based on a self-adaption threshold is designed and the peak recognition rate is 100%. Experiments with different temperatures were conducted to demonstrate the effectiveness of the system. Four FBG sensors were examined in the thermal chamber without stress. When the temperature changed from 0 °C to 100 °C, the degree of linearity between central wavelengths and temperature was about 0.999 with the temperature sensitivity being 10 pm/°C. The static interrogation precision was able to reach 0.5 pm. Through the comparison of different peak detection algorithms and interrogation approaches, the system was verified to have an optimum comprehensive performance in terms of precision, capacity and speed. PMID:29642507
X-ray and neutron interrogation of air cargo for mobile applications
NASA Astrophysics Data System (ADS)
Van Liew, Seth
2015-06-01
A system for scanning break-bulk cargo for mobile applications is presented. This combines a 140 kV multi-view, multi-energy X-ray system with 2.5 MeV neutrons. The system uses dual energy X-ray radiography with neutron radiography. The X-ray and neutron systems were designed to be collocated in a mobile environment. Various materials were interrogated with the intent of distinguishing threat materials such as explosives from similar benign materials. In particular, the identification of threats and bengins with nearly identical effective atomic numbers has been demonstrated.
Active Proton Interrogation for Homeland Security
NASA Astrophysics Data System (ADS)
Greene, Steven; Morris, Christopher; Canavan, Gregory; Chung, Kiwhan; Elson, Jay; Hogan, Gary; Makela, Mark; Mariam, Fesseha; Murray, Matthew; Saunders, Alexander; Spaulding, Randy; Wang, Zhehui; Waters, Laurie; Wysocki, Frederick
2010-02-01
Energetic proton beams may provide an attractive technology for active interrogation of nuclear threats because: they have large fission cross sections, long mean free paths and high penetration, and proton beams can be manipulated with magnetic optics. We have measured time-dependent cross sections for delayed neutrons and gamma rays using 800 MeV protons from the Los Alamos Neutron Science Center and 4 GeV protons from the Brookhaven Alternating Gradient Synchrotron for a set of bare and shielded targets. The results show significant signals from both unshielded and shielded nuclear materials. Results will be presented. )
Spectroscopic neutron detection using composite scintillators
NASA Astrophysics Data System (ADS)
Jovanovic, I.; Foster, A.; Kukharev, V.; Mayer, M.; Meddeb, A.; Nattress, J.; Ounaies, Z.; Trivelpiece, C.
2016-09-01
Shielded special nuclear material (SNM), especially highly enriched uranium, is exceptionally difficult to detect without the use of active interrogation (AI). We are investigating the potential use of low-dose active interrogation to realize simultaneous high-contrast imaging and photofission of SNM using energetic gamma-rays produced by low-energy nuclear reactions, such as 11B(d,nγ)12C and 12C(p,p‧)12C. Neutrons produced via fission are one reliable signature of the presence of SNM and are usually identified by their unique timing characteristics, such as the delayed neutron die-away. Fast neutron spectroscopy may provide additional useful discriminating characteristics for SNM detection. Spectroscopic measurements can be conducted by recoil-based or thermalization and capture-gated detectors; the latter may offer unique advantages since they facilitate low-statistics and event-by-event neutron energy measurements without spectrum unfolding. We describe the results of the development and characterization of a new type of capture-gated spectroscopic neutron detector based on a composite of scintillating polyvinyltoluene and lithium-doped scintillating glass in the form of millimeter-thick rods. The detector achieves >108 neutron-gamma discrimination resulting from its geometric properties and material selection. The design facilitates simultaneous pulse shape and pulse height discrimination, despite the fact that no materials intrinsically capable of pulse shape discrimination have been used to construct the detector. Accurate single-event measurements of neutron energy may be possible even when the energy is relatively low, such as with delayed fission neutrons. Simulation and preliminary measurements using the new composite detector are described, including those conducted using radioisotope sources and the low-dose active interrogation system based on low-energy nuclear reactions.
System and technique for ultrasonic characterization of settling suspensions
Greenwood, Margaret S [Richland, WA; Panetta, Paul D [Richland, WA; Bamberger, Judith A [Richland, WA; Pappas, Richard A [Richland, WA
2006-11-28
A system for determining properties of settling suspensions includes a settling container, a mixer, and devices for ultrasonic interrogation transverse to the settling direction. A computer system controls operation of the mixer and the interrogation devices and records the response to the interrogating as a function of settling time, which is then used to determine suspension properties. Attenuation versus settling time for dilute suspensions, such as dilute wood pulp suspension, exhibits a peak at different settling times for suspensions having different properties, and the location of this peak is used as one mechanism for characterizing suspensions. Alternatively or in addition, a plurality of ultrasound receivers are arranged at different angles to a common transmitter to receive scattering responses at a variety of angles during particle settling. Angular differences in scattering as a function of settling time are also used to characterize the suspension.
Performance Characterization of the Air Force Transformational Satellite 12 kW Hall Thruster
NASA Technical Reports Server (NTRS)
Kamhawi, Hani; Haag, Thomas W.; Smith, Timothy; Herman, Daniel; Huang, Wensheng; Shastry, Rohit; Peterson, Peter; Mathers, Alex
2013-01-01
The STMD GCD ISP project is tasked with developing, maturing, and testing enabling human exploration propulsion requirements and potential designs for advanced high-energy, in-space propulsion systems to support deep-space human exploration and reduce travel time between Earth's orbit and future destinations for human activity. High-power Hall propulsion systems have been identified as enabling technologies and have been the focus of the activities at NASA Glenn-In-house effort to evaluate performance and interrogate operation of NASA designed and manufactured Hall thrusters. Evaluate existing high TRL EP devices that may be suitable for implementation in SEP TDM.
Investigation of Intelligence Activities At Abu Ghraib
2004-08-23
detainees" within Abu Ghraib. It is clear that the interrogation practices of other government agencies led to a loss of accountability at Abu Ghraib. DoD...must document and enforce adherence by other government agencies with established DoD practices and procedures while conducting detainee interrogation...misinterpretation as to accepted practices or confusion occurred due to the proliferation of guidance and information from other theaters of operation
Potential capabilities for compression of information of certain data processing systems
NASA Technical Reports Server (NTRS)
Khodarev, Y. K.; Yevdokimov, V. P.; Pokras, V. M.
1974-01-01
This article undertakes to study a generalized block diagram of a data collection and processing system of a spacecraft in which a number of sensors or outputs of scientific instruments are cyclically interrogated by a commutator, methods of writing the supplementary information in a frame on the example of a certain hypothetical telemetry system, and the influence of statistics of number of active channels in a frame on frame compression factor. The separation of the data compression factor of the collection and processing system of spacecraft into two parts used in this work allows determination of the compression factor of an active frame depending not only on the statistics of activity of channels in the telemetry frame, but also on the method of introduction of the additional address and time information to each frame.
NASA Technical Reports Server (NTRS)
Joncas, K. P.
1972-01-01
Concepts and techniques for identifying and simulating both the steady state and dynamic characteristics of electrical loads for use during integrated system test and evaluation are discussed. The investigations showed that it is feasible to design and develop interrogation and simulation equipment to perform the desired functions. During the evaluation, actual spacecraft loads were interrogated by stimulating the loads with their normal input voltage and measuring the resultant voltage and current time histories. Elements of the circuits were optimized by an iterative process of selecting element values and comparing the time-domain response of the model with those obtained from the real equipment during interrogation.
Rodriguez, George; Jaime, Marcelo; Balakirev, Fedor; Mielke, Chuck H; Azad, Abul; Marshall, Bruce; La Lone, Brandon M; Henson, Bryan; Smilowitz, Laura
2015-06-01
A 100 MHz fiber Bragg grating (FBG) interrogation system is described and applied to strain and pressure sensing. The approach relies on coherent pulse illumination of the FBG sensor with a broadband short pulse from a femtosecond modelocked erbium fiber laser. After interrogation of the FBG sensor, a long multi-kilometer run of single mode fiber is used for chromatic dispersion to temporally stretch the spectral components of the reflected pulse from the FBG sensor. Dynamic strain or pressure induced spectral shifts in the FBG sensor are detected as a pulsed time domain waveform shift after encoding by the chromatic dispersive line. Signals are recorded using a single 35 GHz photodetector and a 50 G Samples per second, 25 GHz bandwidth, digitizing oscilloscope. Application of this approach to high-speed strain sensing in magnetic materials in pulsed magnetic fields to ~150 T is demonstrated. The FBG wavelength shifts are used to study magnetic field driven magnetostriction effects in LaCoO3. A sub-microsecond temporal shift in the FBG sensor wavelength attached to the sample under first order phase change appears as a fractional length change (strain: ΔL/L<10-4) in the material. A second application used FBG sensing of pressure dynamics to nearly 2 GPa in the thermal ignition of the high explosive PBX-9501 is also demonstrated. Both applications demonstrate the use of this FBG interrogation system in dynamical extreme conditions that would otherwise not be possible using traditional FBG interrogation approaches that are deemed too slow to resolve such events.
Wavelength-switched phase interrogator for EFPI sensors with polarization self-calibrated
NASA Astrophysics Data System (ADS)
Xia, Ji; Wang, Fuyin; Luo, Hong; Xiong, Shuidong
2017-10-01
The stability of the demodulation system for extrinsic Fabry-Perot interferometric(EFPI) sensors is significant to dynamic signal recovery. In the wavelength-switched demodulation system, a phase interrogation with a wavelength-switched structure has been presented. Two reflected peaks were in perpendicular polarization direction and switched in the time-domain. However, the operation point of system affected output of the linearly-polarized beams seriously, and the stability of the system decreased and even failed to work. In order to solve this problem, a polarization control unit is added into the system in this paper. The modified demodulation system has been demonstrated to have a higher stability.
High-Speed Interrogation for Large-Scale Fiber Bragg Grating Sensing
Hu, Chenyuan; Bai, Wei
2018-01-01
A high-speed interrogation scheme for large-scale fiber Bragg grating (FBG) sensing arrays is presented. This technique employs parallel computing and pipeline control to modulate incident light and demodulate the reflected sensing signal. One Electro-optic modulator (EOM) and one semiconductor optical amplifier (SOA) were used to generate a phase delay to filter reflected spectrum form multiple candidate FBGs with the same optical path difference (OPD). Experimental results showed that the fastest interrogation delay time for the proposed method was only about 27.2 us for a single FBG interrogation, and the system scanning period was only limited by the optical transmission delay in the sensing fiber owing to the multiple simultaneous central wavelength calculations. Furthermore, the proposed FPGA-based technique had a verified FBG wavelength demodulation stability of ±1 pm without average processing. PMID:29495263
High-Speed Interrogation for Large-Scale Fiber Bragg Grating Sensing.
Hu, Chenyuan; Bai, Wei
2018-02-24
A high-speed interrogation scheme for large-scale fiber Bragg grating (FBG) sensing arrays is presented. This technique employs parallel computing and pipeline control to modulate incident light and demodulate the reflected sensing signal. One Electro-optic modulator (EOM) and one semiconductor optical amplifier (SOA) were used to generate a phase delay to filter reflected spectrum form multiple candidate FBGs with the same optical path difference (OPD). Experimental results showed that the fastest interrogation delay time for the proposed method was only about 27.2 us for a single FBG interrogation, and the system scanning period was only limited by the optical transmission delay in the sensing fiber owing to the multiple simultaneous central wavelength calculations. Furthermore, the proposed FPGA-based technique had a verified FBG wavelength demodulation stability of ±1 pm without average processing.
Surface Acoustic Wave Tag-Based Coherence Multiplexing
NASA Technical Reports Server (NTRS)
Youngquist, Robert C. (Inventor); Malocha, Donald (Inventor); Saldanha, Nancy (Inventor)
2016-01-01
A surface acoustic wave (SAW)-based coherence multiplexing system includes SAW tags each including a SAW transducer, a first SAW reflector positioned a first distance from the SAW transducer and a second SAW reflector positioned a second distance from the SAW transducer. A transceiver including a wireless transmitter has a signal source providing a source signal and circuitry for transmitting interrogation pulses including a first and a second interrogation pulse toward the SAW tags, and a wireless receiver for receiving and processing response signals from the SAW tags. The receiver receives scrambled signals including a convolution of the wideband interrogation pulses with response signals from the SAW tags and includes a computing device which implements an algorithm that correlates the interrogation pulses or the source signal before transmitting against the scrambled signals to generate tag responses for each of the SAW tags.
Active neutron and gamma-ray imaging of highly enriched uranium for treaty verification
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hamel, Michael C.; Polack, J. Kyle; Ruch, Marc L.
The detection and characterization of highly enriched uranium (HEU) presents a large challenge in the non-proliferation field. HEU has a low neutron emission rate and most gamma rays are low energy and easily shielded. To address this challenge, an instrument known as the dual-particle imager (DPI) was used with a portable deuterium-tritium (DT) neutron generator to detect neutrons and gamma rays from induced fission in HEU. We evaluated system response using a 13.7-kg HEU sphere in several configurations with no moderation, high-density polyethylene (HDPE) moderation, and tungsten moderation. A hollow tungsten sphere was interrogated to evaluate the response to amore » possible hoax item. First, localization capabilities were demonstrated by reconstructing neutron and gamma-ray images. Once localized, additional properties such as fast neutron energy spectra and time-dependent neutron count rates were attributed to the items. For the interrogated configurations containing HEU, the reconstructed neutron spectra resembled Watt spectra, which gave confidence that the interrogated items were undergoing induced fission. The time-dependent neutron count rate was also compared for each configuration and shown to be dependent on the neutron multiplication of the item. This result showed that the DPI is a viable tool for localizing and confirming fissile mass and multiplication.« less
Active neutron and gamma-ray imaging of highly enriched uranium for treaty verification
Hamel, Michael C.; Polack, J. Kyle; Ruch, Marc L.; ...
2017-08-11
The detection and characterization of highly enriched uranium (HEU) presents a large challenge in the non-proliferation field. HEU has a low neutron emission rate and most gamma rays are low energy and easily shielded. To address this challenge, an instrument known as the dual-particle imager (DPI) was used with a portable deuterium-tritium (DT) neutron generator to detect neutrons and gamma rays from induced fission in HEU. We evaluated system response using a 13.7-kg HEU sphere in several configurations with no moderation, high-density polyethylene (HDPE) moderation, and tungsten moderation. A hollow tungsten sphere was interrogated to evaluate the response to amore » possible hoax item. First, localization capabilities were demonstrated by reconstructing neutron and gamma-ray images. Once localized, additional properties such as fast neutron energy spectra and time-dependent neutron count rates were attributed to the items. For the interrogated configurations containing HEU, the reconstructed neutron spectra resembled Watt spectra, which gave confidence that the interrogated items were undergoing induced fission. The time-dependent neutron count rate was also compared for each configuration and shown to be dependent on the neutron multiplication of the item. This result showed that the DPI is a viable tool for localizing and confirming fissile mass and multiplication.« less
Bioinformatic approaches to interrogating vitamin D receptor signaling.
Campbell, Moray J
2017-09-15
Bioinformatics applies unbiased approaches to develop statistically-robust insight into health and disease. At the global, or "20,000 foot" view bioinformatic analyses of vitamin D receptor (NR1I1/VDR) signaling can measure where the VDR gene or protein exerts a genome-wide significant impact on biology; VDR is significantly implicated in bone biology and immune systems, but not in cancer. With a more VDR-centric, or "2000 foot" view, bioinformatic approaches can interrogate events downstream of VDR activity. Integrative approaches can combine VDR ChIP-Seq in cell systems where significant volumes of publically available data are available. For example, VDR ChIP-Seq studies can be combined with genome-wide association studies to reveal significant associations to immune phenotypes. Similarly, VDR ChIP-Seq can be combined with data from Cancer Genome Atlas (TCGA) to infer the impact of VDR target genes in cancer progression. Therefore, bioinformatic approaches can reveal what aspects of VDR downstream networks are significantly related to disease or phenotype. Copyright © 2017 The Author. Published by Elsevier B.V. All rights reserved.
A robust activity marking system for exploring active neuronal ensembles
Sørensen, Andreas T; Cooper, Yonatan A; Baratta, Michael V; Weng, Feng-Ju; Zhang, Yuxiang; Ramamoorthi, Kartik; Fropf, Robin; LaVerriere, Emily; Xue, Jian; Young, Andrew; Schneider, Colleen; Gøtzsche, Casper René; Hemberg, Martin; Yin, Jerry CP; Maier, Steven F; Lin, Yingxi
2016-01-01
Understanding how the brain captures transient experience and converts it into long lasting changes in neural circuits requires the identification and investigation of the specific ensembles of neurons that are responsible for the encoding of each experience. We have developed a Robust Activity Marking (RAM) system that allows for the identification and interrogation of ensembles of neurons. The RAM system provides unprecedented high sensitivity and selectivity through the use of an optimized synthetic activity-regulated promoter that is strongly induced by neuronal activity and a modified Tet-Off system that achieves improved temporal control. Due to its compact design, RAM can be packaged into a single adeno-associated virus (AAV), providing great versatility and ease of use, including application to mice, rats, flies, and potentially many other species. Cre-dependent RAM, CRAM, allows for the study of active ensembles of a specific cell type and anatomical connectivity, further expanding the RAM system’s versatility. DOI: http://dx.doi.org/10.7554/eLife.13918.001 PMID:27661450
Zhang, Jing; Liu, Xiaojun; Xu, Wenjing; Luo, Wenhan; Li, Ming; Chu, Fangbing; Xu, Lu; Cao, Anyuan; Guan, Jisong; Tang, Shiming; Duan, Xiaojie
2018-05-09
Recent developments of transparent electrode arrays provide a unique capability for simultaneous optical and electrical interrogation of neural circuits in the brain. However, none of these electrode arrays possess the stretchability highly desired for interfacing with mechanically active neural systems, such as the brain under injury, the spinal cord, and the peripheral nervous system (PNS). Here, we report a stretchable transparent electrode array from carbon nanotube (CNT) web-like thin films that retains excellent electrochemical performance and broad-band optical transparency under stretching and is highly durable under cyclic stretching deformation. We show that the CNT electrodes record well-defined neuronal response signals with negligible light-induced artifacts from cortical surfaces under optogenetic stimulation. Simultaneous two-photon calcium imaging through the transparent CNT electrodes from cortical surfaces of GCaMP-expressing mice with epilepsy shows individual activated neurons in brain regions from which the concurrent electrical recording is taken, thus providing complementary cellular information in addition to the high-temporal-resolution electrical recording. Notably, the studies on rats show that the CNT electrodes remain operational during and after brain contusion that involves the rapid deformation of both the electrode array and brain tissue. This enables real-time, continuous electrophysiological monitoring of cortical activity under traumatic brain injury. These results highlight the potential application of the stretchable transparent CNT electrode arrays in combining electrical and optical modalities to study neural circuits, especially under mechanically active conditions, which could potentially provide important new insights into the local circuit dynamics of the spinal cord and PNS as well as the mechanism underlying traumatic injuries of the nervous system.
Revisiting the False Confession Problem.
Alvarez-Toro, Viviana; Lopez-Morales, Cesar A
2018-03-01
Despite the existence of important safeguards in our criminal legal system, innocent suspects often succumb to forceful and deceptive interrogation techniques. Among those over-represented members of the false confessor population are minors, people with cognitive and intellectual disabilities, and those with psychiatric disorders. Some of the confessions made by these at-risk populations can hardly be considered voluntary or reliable, but they are generally admitted at trial, regardless of their prejudicial effect. Forensic psychiatrists should become more involved in the overall process of evaluating confessions, not only testifying in courts, but also assisting policymakers in reforming the interrogation process and influencing the legal process. Thus, forensic psychiatrists may give their expert opinion by providing proper training to police interrogators and examining videotaped interrogations. In addition, forensic experts can be instrumental in contributing to three legal solutions that we propose to the false confession problem: a constitutional approach, an evidence law approach, and a jury instruction approach. Each of these approaches requires forensic psychiatrists to help judges and jurors understand the coercive nature of the interrogation process and its effect on suspects' behavior. © 2018 American Academy of Psychiatry and the Law.
Monitoring system including an electronic sensor platform and an interrogation transceiver
Kinzel, Robert L.; Sheets, Larry R.
2003-09-23
A wireless monitoring system suitable for a wide range of remote data collection applications. The system includes at least one Electronic Sensor Platform (ESP), an Interrogator Transceiver (IT) and a general purpose host computer. The ESP functions as a remote data collector from a number of digital and analog sensors located therein. The host computer provides for data logging, testing, demonstration, installation checkout, and troubleshooting of the system. The IT transmits signals from one or more ESP's to the host computer to the ESP's. The IT host computer may be powered by a common power supply, and each ESP is individually powered by a battery. This monitoring system has an extremely low power consumption which allows remote operation of the ESP for long periods; provides authenticated message traffic over a wireless network; utilizes state-of-health and tamper sensors to ensure that the ESP is secure and undamaged; has robust housing of the ESP suitable for use in radiation environments; and is low in cost. With one base station (host computer and interrogator transceiver), multiple ESP's may be controlled at a single monitoring site.
Can active proton interrogation find shielded nuclear threats at human-safe radiation levels?
NASA Astrophysics Data System (ADS)
Liew, Seth Van
2017-05-01
A new method of low-dose proton radiography is presented. The system is composed of an 800 MeV proton source, bending magnets, and compact detectors, and is designed for drive-through cargo scanning. The system has been simulated using GEANT4. Material identification algorithms and pixel sorting methods are presented that allow the system to perform imaging at doses low enough to scan passenger vehicles and people. Results are presented on imaging efficacy of various materials and cluttered cargoes. The identification of shielded nuclear materials at human-safe doses has been demonstrated.
Development of Techniques for Spent Fuel Assay – Differential Dieaway Final Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swinhoe, Martyn Thomas; Goodsell, Alison; Ianakiev, Kiril Dimitrov
This report summarizes the work done under a DNDO R&D funded project on the development of the differential dieaway method to measure plutonium in spent fuel. There are large amounts of plutonium that are contained in spent fuel assemblies, and currently there is no way to make quantitative non-destructive assay. This has led NA24 under the Next Generation Safeguards Initiative (NGSI) to establish a multi-year program to investigate, develop and implement measurement techniques for spent fuel. The techniques which are being experimentally tested by the existing NGSI project do not include any pulsed neutron active techniques. The present work coversmore » the active neutron differential dieaway technique and has advanced the state of knowledge of this technique as well as produced a design for a practical active neutron interrogation instrument for spent fuel. Monte Carlo results from the NGSI effort show that much higher accuracy (1-2%) for the Pu content in spent fuel assemblies can be obtained with active neutron interrogation techniques than passive techniques, and this would allow their use for nuclear material accountancy independently of any information from the operator. The main purpose of this work was to develop an active neutron interrogation technique for spent nuclear fuel.« less
Orbiter CIU/IUS communications hardware evaluation
NASA Technical Reports Server (NTRS)
Huth, G. K.
1979-01-01
The DOD and NASA inertial upper stage communication system design, hardware specifications and interfaces were analyzed to determine their compatibility with the Orbiter payload communications equipment (Payload Interrogator, Payload Signal Processors, Communications Interface Unit, and the Orbiter operational communications equipment (the S-Band and Ku-band systems). Topics covered include (1) IUS/shuttle Orbiter communications interface definition; (2) Orbiter avionics equipment serving the IUS; (3) IUS communication equipment; (4) IUS/shuttle Orbiter RF links; (5) STDN/TDRS S-band related activities; and (6) communication interface unit/Orbiter interface issues. A test requirement plan overview is included.
Systems, Apparatuses and Methods for Beamforming RFID Tags
NASA Technical Reports Server (NTRS)
Fink, Patrick W. (Inventor); Lin, Gregory Y. (Inventor); Ngo, Phong H. (Inventor); Kennedy, Timothy F. (Inventor)
2017-01-01
A radio frequency identification (RFID) system includes an RFID interrogator and an RFID tag having a plurality of information sources and a beamforming network. The tag receives electromagnetic radiation from the interrogator. The beamforming network directs the received electromagnetic radiation to a subset of the plurality of information sources. The RFID tag transmits a response to the received electromagnetic radiation, based on the subset of the plurality of information sources to which the received electromagnetic radiation was directed. Method and other embodiments are also disclosed.
RFID Torque Sensing Tag System for Fasteners
NASA Technical Reports Server (NTRS)
Fink, Patrick W. (Inventor); Lin, Gregory Y. (Inventor); Ngo, Phong H. (Inventor); Kennedy, Timothy F. (Inventor)
2016-01-01
The present invention provides an RFID-based torque sensor that can be used to quickly monitor off the shelf fasteners including fasteners that are used in expensive satellites or other uses where fastener failure can be very costly. In one embodiment, an antenna, RFID ring and spring comprise a sensor tag that can be interrogated with an interrogation signal produced by an interrogator device. When sufficient torque is applied to the fastener, an RFID circuit is connected, and produces a radio frequency (RF) signal that can be read by the interrogator. In one embodiment, the RFID circuit does not transmit when the spring member is not compressed, thereby indicating insufficient tensioning of the fastener. The present invention offers the ability to remotely, quickly, and inexpensively verify that any number of fasteners are torqued properly upon initial installation. Where applicable, the present invention allows low cost monitoring over the life of the fastener.
Ricchiuti, Amelia Lavinia; Barrera, David; Sales, Salvador; Thevenaz, Luc; Capmany, José
2013-11-18
A novel technique for interrogating photonic sensors based on long fiber Bragg gratings (FBGs) is presented and experimentally demonstrated, dedicated to detect the presence and the precise location of several spot events. The principle of operation is based on a technique used to analyze microwave photonics (MWP) filters. The long FBGs are used as quasi-distributed sensors. Several hot-spots can be detected along the FBG with a spatial accuracy under 0.5 mm using a modulator and a photo-detector (PD) with a modest bandwidth of less than 1 GHz. The proposed interrogation system is intrinsically robust against environmental changes.
Doronina-Amitonova, L. V.; Fedotov, I. V.; Ivashkina, O. I.; Zots, M. A.; Fedotov, A. B.; Anokhin, K. V.; Zheltikov, A. M.
2013-01-01
Seeing the big picture of functional responses within large neural networks in a freely functioning brain is crucial for understanding the cellular mechanisms behind the higher nervous activity, including the most complex brain functions, such as cognition and memory. As a breakthrough toward meeting this challenge, implantable fiber-optic interfaces integrating advanced optogenetic technologies and cutting-edge fiber-optic solutions have been demonstrated, enabling a long-term optogenetic manipulation of neural circuits in freely moving mice. Here, we show that a specifically designed implantable fiber-optic interface provides a powerful tool for parallel long-term optical interrogation of distinctly separate, functionally different sites in the brain of freely moving mice. This interface allows the same groups of neurons lying deeply in the brain of a freely behaving mouse to be reproducibly accessed and optically interrogated over many weeks, providing a long-term dynamic detection of genome activity in response to a broad variety of pharmacological and physiological stimuli. PMID:24253232
NASA Astrophysics Data System (ADS)
Doronina-Amitonova, L. V.; Fedotov, I. V.; Ivashkina, O. I.; Zots, M. A.; Fedotov, A. B.; Anokhin, K. V.; Zheltikov, A. M.
2013-11-01
Seeing the big picture of functional responses within large neural networks in a freely functioning brain is crucial for understanding the cellular mechanisms behind the higher nervous activity, including the most complex brain functions, such as cognition and memory. As a breakthrough toward meeting this challenge, implantable fiber-optic interfaces integrating advanced optogenetic technologies and cutting-edge fiber-optic solutions have been demonstrated, enabling a long-term optogenetic manipulation of neural circuits in freely moving mice. Here, we show that a specifically designed implantable fiber-optic interface provides a powerful tool for parallel long-term optical interrogation of distinctly separate, functionally different sites in the brain of freely moving mice. This interface allows the same groups of neurons lying deeply in the brain of a freely behaving mouse to be reproducibly accessed and optically interrogated over many weeks, providing a long-term dynamic detection of genome activity in response to a broad variety of pharmacological and physiological stimuli.
PRESTO-Tango as an open-source resource for interrogation of the druggable human GPCRome.
Kroeze, Wesley K; Sassano, Maria F; Huang, Xi-Ping; Lansu, Katherine; McCorvy, John D; Giguère, Patrick M; Sciaky, Noah; Roth, Bryan L
2015-05-01
G protein-coupled receptors (GPCRs) are essential mediators of cellular signaling and are important targets of drug action. Of the approximately 350 nonolfactory human GPCRs, more than 100 are still considered to be 'orphans' because their endogenous ligands remain unknown. Here, we describe a unique open-source resource that allows interrogation of the druggable human GPCRome via a G protein-independent β-arrestin-recruitment assay. We validate this unique platform at more than 120 nonorphan human GPCR targets, demonstrate its utility for discovering new ligands for orphan human GPCRs and describe a method (parallel receptorome expression and screening via transcriptional output, with transcriptional activation following arrestin translocation (PRESTO-Tango)) for the simultaneous and parallel interrogation of the entire human nonolfactory GPCRome.
Rodriguez, George; Jaime, Marcelo; Balakirev, Fedor; ...
2015-05-21
A 100 MHz fiber Bragg grating (FBG) interrogation system is described and applied to strain and pressure sensing. The approach relies on coherent pulse illumination of the FBG sensor with a broadband short pulse from a femtosecond modelocked erbium fiber laser. After interrogation of the FBG sensor, a long multi-kilometer run of single mode fiber is used for chromatic dispersion to temporally stretch the spectral components of the reflected pulse from the FBG sensor. Dynamic strain or pressure induced spectral shifts in the FBG sensor are detected as a pulsed time domain waveform shift after encoding by the chromatic dispersivemore » line. Signals are recorded using a single 35 GHz photodetector and a 50 GSamples per second, 25 GHz bandwidth, digitizing oscilloscope. Application of this approach to high-speed strain sensing in magnetic materials in pulsed magnetic fields to ~150 T is demonstrated. The FBG wavelength shifts are used to study magnetic field driven magnetostriction effects in LaCoO₃. A sub-microsecond temporal shift in the FBG sensor wavelength attached to the sample under first order phase change appears as a fractional length change (strain: ΔL/L<10⁻⁴) in the material. A second application used FBG sensing of pressure dynamics to nearly 2 GPa in the thermal ignition of the high explosive PBX-9501 is also demonstrated. In conclusion, both applications demonstrate the use of this FBG interrogation system in dynamical extreme conditions that would otherwise not be possible using traditional FBG interrogation approaches that are deemed too slow to resolve such events.« less
Building a COTS archive for satellite data
NASA Technical Reports Server (NTRS)
Singer, Ken; Terril, Dave; Kelly, Jack; Nichols, Cathy
1994-01-01
The goal of the NOAA/NESDIS Active Archive was to provide a method of access to an online archive of satellite data. The archive had to manage and store the data, let users interrogate the archive, and allow users to retrieve data from the archive. Practical issues of the system design such as implementation time, cost and operational support were examined in addition to the technical issues. There was a fixed window of opportunity to create an operational system, along with budget and staffing constraints. Therefore, the technical solution had to be designed and implemented subject to constraint imposed by the practical issues. The NOAA/NESDIS Active Archive came online in July of 1994, meeting all of its original objectives.
First Deminsys (high speed FBG interrogator) flight
NASA Astrophysics Data System (ADS)
van Els, Thomas J.
2009-03-01
Deminsys is the world's fastest multi sensor / multi channel FBG interrogator, identifies one till four channels with typically 8 sensors per channel. The system is especially developed for the interrogation of signals up to 19,3 kHz for each sensor and the sample frequency is independent of the number of sensors. By having multiple sensors per fibre you can create a very compact network of sensors. Due to its revolutionary (light weight, compact and solid state) design, Deminsys seems to fit perfectly into (research) programs for aerospace, medic & life science, maritime, industrial, crash test and all other fast detection applications. Technobis Fibre Technologies (TFT) and NLR made a first test flight with the Deminsys optical fibre measurement system using the NLR test aircraft on October 24th 2008. This flight was a first step in the further development of the current system in order to make it suitable for operation on-board an aircraft and bring it from TRL3 towards TRL5, a functional model for aerospace applications.
Detecting concealed objects at a checkpoint
McMakin, Douglas L [Richland, WA; Hall, Thomas E [Kennewick, WA; Sheen, David M [Richland, WA; Severtsen, Ronald H [Richland, WA
2008-07-29
Disclosed are systems, methods, devices, and apparatus to interrogate a clothed individual with electromagnetic radiation to determine if a concealed object is being carried. This determination includes establishing data corresponding to an image of the individual with a pair of opposed, semi-cylindrical array panels each configured to interrogate the individual with electromagnetic radiation in the 200 MHz to 1 THz range.
In-field tests of the EURITRACK tagged neutron inspection system
NASA Astrophysics Data System (ADS)
Carasco, C.; Perot, B.; Bernard, S.; Mariani, A.; Szabo, J.-L.; Sannie, G.; Roll, Th.; Valkovic, V.; Sudac, D.; Viesti, G.; Lunardon, M.; Bottosso, C.; Fabris, D.; Nebbia, G.; Pesente, S.; Moretto, S.; Zenoni, A.; Donzella, A.; Moszynski, M.; Gierlik, M.; Batsch, T.; Wolski, D.; Klamra, W.; Le Tourneur, P.; Lhuissier, M.; Colonna, A.; Tintori, C.; Peerani, P.; Sequeira, V.; Salvato, M.
2008-04-01
The EURopean Illicit TRAfficking Countermeasures Kit (EURITRACK) inspection system has been designed to complement X-ray scanners in the detection of explosives and other illicit materials hidden in cargo containers. The containers are interrogated by a 14-MeV tagged neutron beam at any suspect position in the X-ray image. Interrogation of a specific volume element with tagged neutrons yields information about the chemical composition of the material. Implementation and performance tests of the EURITRACK system in the Port of Rijeka in Croatia are described. Cargo container inspection results are reported and discussed.
Design of a photonic integrated based optical interrogator
NASA Astrophysics Data System (ADS)
Ibrahim, Selwan K.; Farnan, Martin; Karabacak, Devrez M.
2017-02-01
Optical sensors based on Fiber Bragg Gratings (FBGs) are used in several applications and industries. In order for fiber optic sensors to compete with electrical sensors, several critical parameters of both the sensors and sensor interrogators need to be in place such as performance, cost, size, reliability relevant to the target application. Here we have developed a tunable laser based optical interrogator which delivers high performance (up to 8kHz sweep-rate and 120dB dynamic range) and precision (<100fm) by optimizing the laser calibration of a telecom tunable laser and incorporating optical periodic wavelength references (e.g. MZI) to correct and compensate for wavelength non-linearity and noise during operation. Scaling up optical sensing systems to deliver high level of performance over a large number of sensors is enabled by synchronizing multiple interrogators. Further improvements can be achieved by using photonic integrated circuit (PIC) technology which reduces the footprint, cost, and improves performance. There exists several PIC technology platforms (e.g. InP, Si, TriPlex) that could be used to develop different optical building blocks used in the interrogator. Such building blocks include the tunable laser, couplers, photodiodes, MZIs, etc. are available on the InP platform. Here we have demonstrated the operation of an interrogator using PIC technology to replace many of the discrete optical components. The design and chip manufacturing was carried out as part of an InP multi-project wafer (MPW) run under the EU PARADIGM project. A custom package supporting fiber arrays was designed and manufactured to demonstrate the PIC functionality in an optical interrogator.
Duan, Litian; Wang, Zizhong John; Duan, Fu
2016-11-16
In the multiple-reader environment (MRE) of radio frequency identification (RFID) system, multiple readers are often scheduled to interrogate the randomized tags via operating at different time slots or frequency channels to decrease the signal interferences. Based on this, a Geometric Distribution-based Multiple-reader Scheduling Optimization Algorithm using Artificial Immune System (GD-MRSOA-AIS) is proposed to fairly and optimally schedule the readers operating from the viewpoint of resource allocations. GD-MRSOA-AIS is composed of two parts, where a geometric distribution function combined with the fairness consideration is first introduced to generate the feasible scheduling schemes for reader operation. After that, artificial immune system (including immune clone, immune mutation and immune suppression) quickly optimize these feasible ones as the optimal scheduling scheme to ensure that readers are fairly operating with larger effective interrogation range and lower interferences. Compared with the state-of-the-art algorithm, the simulation results indicate that GD-MRSOA-AIS could efficiently schedules the multiple readers operating with a fairer resource allocation scheme, performing in larger effective interrogation range.
Duan, Litian; Wang, Zizhong John; Duan, Fu
2016-01-01
In the multiple-reader environment (MRE) of radio frequency identification (RFID) system, multiple readers are often scheduled to interrogate the randomized tags via operating at different time slots or frequency channels to decrease the signal interferences. Based on this, a Geometric Distribution-based Multiple-reader Scheduling Optimization Algorithm using Artificial Immune System (GD-MRSOA-AIS) is proposed to fairly and optimally schedule the readers operating from the viewpoint of resource allocations. GD-MRSOA-AIS is composed of two parts, where a geometric distribution function combined with the fairness consideration is first introduced to generate the feasible scheduling schemes for reader operation. After that, artificial immune system (including immune clone, immune mutation and immune suppression) quickly optimize these feasible ones as the optimal scheduling scheme to ensure that readers are fairly operating with larger effective interrogation range and lower interferences. Compared with the state-of-the-art algorithm, the simulation results indicate that GD-MRSOA-AIS could efficiently schedules the multiple readers operating with a fairer resource allocation scheme, performing in larger effective interrogation range. PMID:27854342
Measurement and analysis of gamma-rays emitted from spent nuclear fuel above 3 MeV.
Rodriguez, Douglas C; Anderson, Elaina; Anderson, Kevin K; Campbell, Luke W; Fast, James E; Jarman, Kenneth; Kulisek, Jonathan; Orton, Christopher R; Runkle, Robert C; Stave, Sean
2013-12-01
The gamma-ray spectrum of spent nuclear fuel in the 3-6 MeV energy range is important for active interrogation since gamma rays emitted from nuclear decay are not expected to interfere with measurements in this energy region. There is, unfortunately, a dearth of empirical measurements from spent nuclear fuel in this region. This work is an initial attempt to partially fill this gap by presenting an analysis of gamma-ray spectra collected from a set of spent nuclear fuel sources using a high-purity germanium detector array. This multi-crystal array possesses a large collection volume, providing high energy resolution up to 16 MeV. The results of these measurements establish the continuum count-rate in the energy region between 3 and 6 MeV. Also assessed is the potential for peaks from passive emissions to interfere with peak measurements resulting from active interrogation delayed emissions. As one of the first documented empirical measurements of passive emissions from spent fuel for energies above 3 MeV, this work provides a foundation for active interrogation model validation and detector development. © 2013 Elsevier Ltd. All rights reserved.
Flow cytometer acquisition and detection system
Casstevens, Martin K.; Burzynski, Ryszard; Weibel, John; Kachynski, Alexander
2010-05-04
A flow cytometer has a flow cell through which a sample flows and at least one laser emitting an excitation beam for illuminating a corresponding interrogation region in the flow cell. Scattered and fluorescence light from each interrogation region is collected by one or more input fibers for that region, and the input fiber(s) are fed to a dispersion module for that interrogation region that disperses the incoming light into different spectral regions. The dispersed light is conveyed, such as by a plurality of output fibers, to one or more photosensitive detectors. Thus, time multiplexed light signals may be delivered to a detector whereby several unique light signals can be measured by a single detector.
Interrogation of weak Bragg grating sensors based on dual-wavelength differential detection.
Cheng, Rui; Xia, Li
2016-11-15
It is shown that for weak Bragg gratings the logarithmic ratio of reflected intensities at any two wavelengths within the spectrum follows a linear relationship with the Bragg wavelength shift, with a slope proportional to their wavelength spacing. This finding is exploited to develop a flexible, efficient, and cheap interrogation solution of weak fiber Bragg grating (FBGs), especially ultra-short FBGs, in distributed sensing based on dual-wavelength differential detection. The concept is experimentally studied in both single and distributed sensing systems with ultra-short FBG sensors. The work may form the basis of new and promising FBG interrogation techniques based on detecting discrete rather than continuous spectra.
Surface plasmon resonance sensor using vari-focal liquid lens under angular interrogation
NASA Astrophysics Data System (ADS)
Lee, Muyoung; Bang, Yousung; Lee, Jooho; Jang, Wonjae; Won, Yong Hyub
2017-02-01
In this paper, a surface plasmon resonance sensor for the detection of refractive index variation is presented. A novel waveguide type surface plasmon resonance sensing configuration with focal length variable liquid lens is introduced. The method of surface plasmon resonance sensor is based on the waveguide type with incident angle variation. The incident angle is varied by using an electrowetting liquid lens which is possible to actively change focal length as applying voltage. The optical system, which is adapted to electrowetting lens can continuously change the incident angle of light from 73 to 78 degrees with compact size. The surface plasmon waves are excited between metal and dielectric interface. The sensing surfaces are prepared by a coating of gold metal above high refractive index glass substrate. The incident light which is 532nm monochromatic light source passes through a noble metal coated substrate to detect intensity with incident angle variation. An analysis to distinguish the contribution of light with various incident angle is focused on the angular characteristics of the surface plasmon sensor under wavelength interrogation. The resonance angle is determined corresponding to sensing material refractive index with high sensitivity. The result suggests that the performance of surface plasmon resonance sensor can be improved by real time varying incident angle. From this presented study, it provides a different approach for angular interrogation surface plasmon resonance sensor and can be miniaturized for a portable device.
Long, Ruiqi; McShane, Mike
2012-09-01
Implantable luminescent sensors are being developed for on-demand monitoring of blood glucose levels. For these sensors to be deployed in vivo, a matched external hardware system is needed. In this paper, we designed a compact, low-cost optical system with highly efficient photon delivery and collection using advanced optical modeling software. Compared to interrogation with a fiber bundle, the new system was predicted to improve interrogation efficiency by a factor of 200 for native sensors; an improvement of 37 times was predicted for sensors implanted at a depth of 1 mm in a skin-simulating phantom. A physical prototype was tested using silicone-based skin phantoms developed specifically to mimic the scattering and absorbing properties of human skin. The experimental evaluations revealed that the prototype device performed in agreement with expectations from simulation results, resulting in an overall improvement of over 2000 times. This efficient system enables use of a low-cost commercial spectrometer for recording sensor emission, which was not possible using only fiber optic delivery and collection, and will be used as a tool for in vivo studies with animal models or human subjects.
Gudjonsson, G H
1988-05-01
This paper attempts to investigate empirically in 30 subjects some of the theoretical components related to individual differences that are thought by Gudjonsson & Clark (1986) to mediate interrogative suggestibility as measured by the Gudjonsson Suggestibility Scale (GSS; Gudjonsson, 1984a). The variables studied were: assertiveness, social-evaluative anxiety, state anxiety and the coping methods subjects are able to generate and implement during interrogation. Low assertiveness and high evaluative anxiety were found to correlate moderately with suggestibility, but no significant correlations emerged for 'social avoidance and distress'. State anxiety correlated significantly with suggestibility, particularly after negative feedback had been administered. Coping methods (active-cognitive/behavioural vs. avoidance) significantly predicted suggestibility scores. The findings give strong support to the theoretical model of Gudjonsson & Clark.
Functional interrogation of non-coding DNA through CRISPR genome editing
Canver, Matthew C.; Bauer, Daniel E.; Orkin, Stuart H.
2017-01-01
Methodologies to interrogate non-coding regions have lagged behind coding regions despite comprising the vast majority of the genome. However, the rapid evolution of clustered regularly interspaced short palindromic repeats (CRISPR)-based genome editing has provided a multitude of novel techniques for laboratory investigation including significant contributions to the toolbox for studying non-coding DNA. CRISPR-mediated loss-of-function strategies rely on direct disruption of the underlying sequence or repression of transcription without modifying the targeted DNA sequence. CRISPR-mediated gain-of-function approaches similarly benefit from methods to alter the targeted sequence through integration of customized sequence into the genome as well as methods to activate transcription. Here we review CRISPR-based loss- and gain-of-function techniques for the interrogation of non-coding DNA. PMID:28288828
NASA Astrophysics Data System (ADS)
Van Liew, Seth; Bertozzi, William; D'Olympia, Nathan; Franklin, Wilbur A.; Korbly, Stephen E.; Ledoux, Robert J.; Wilson, Cody M.
A x-ray inspection system utilizing a continuous-wave 9 MeV rhodotron x-ray source for scanning cargo containers is presented. This system scans for contraband, anomalies, stowaway passengers, and nuclear threats for trucks and towed cargo containers. A transmission image is generated concurrently with a 3D image of the cargo, the latter presenting material information in the form of atomic number and density. Neutrons from photofission are also detected during each scan. In addition, nuclear resonance fluorescence detectors are capable of identifying specific isotopes. This system has recently been deployed at the Port of Boston.
Integrated nanoscale tools for interrogating living cells
NASA Astrophysics Data System (ADS)
Jorgolli, Marsela
The development of next-generation, nanoscale technologies that interface biological systems will pave the way towards new understanding of such complex systems. Nanowires -- one-dimensional nanoscale structures -- have shown unique potential as an ideal physical interface to biological systems. Herein, we focus on the development of nanowire-based devices that can enable a wide variety of biological studies. First, we built upon standard nanofabrication techniques to optimize nanowire devices, resulting in perfectly ordered arrays of both opaque (Silicon) and transparent (Silicon dioxide) nanowires with user defined structural profile, densities, and overall patterns, as well as high sample consistency and large scale production. The high-precision and well-controlled fabrication method in conjunction with additional technologies laid the foundation for the generation of highly specialized platforms for imaging, electrochemical interrogation, and molecular biology. Next, we utilized nanowires as the fundamental structure in the development of integrated nanoelectronic platforms to directly interrogate the electrical activity of biological systems. Initially, we generated a scalable intracellular electrode platform based on vertical nanowires that allows for parallel electrical interfacing to multiple mammalian neurons. Our prototype device consisted of 16 individually addressable stimulation/recording sites, each containing an array of 9 electrically active silicon nanowires. We showed that these vertical nanowire electrode arrays could intracellularly record and stimulate neuronal activity in dissociated cultures of rat cortical neurons similar to patch clamp electrodes. In addition, we used our intracellular electrode platform to measure multiple individual synaptic connections, which enables the reconstruction of the functional connectivity maps of neuronal circuits. In order to expand and improve the capability of this functional prototype device we designed and fabricated a new hybrid chip that combines a front-side nanowire-based interface for neuronal recording with backside complementary metal oxide semiconductor (CMOS) circuits for on-chip multiplexing, voltage control for stimulation, signal amplification, and signal processing. Individual chips contain 1024 stimulation/recording sites enabling large-scale interfacing of neuronal networks with single cell resolution. Through electrical and electrochemical characterization of the devices, we demonstrated their enhanced functionality at a massively parallel scale. In our initial cell experiments, we achieved intracellular stimulations and recordings of changes in the membrane potential in a variety of cells including: HEK293T, cardiomyocytes, and rat cortical neurons. This demonstrated the device capability for single-cell-resolution recording/stimulation which when extended to a large number of neurons in a massively parallel fashion will enable the functional mapping of a complex neuronal network.
NASA Astrophysics Data System (ADS)
Li, Ming; Sun, Zhihui; Zhang, Xiaolei; Li, Shujuan; Song, Zhiqiang; Wang, Meng; Guo, Jian; Ni, Jiasheng; Wang, Chang; Peng, Gangding; Xu, Xiangang
2017-09-01
Fiber laser hydrophones have got widespread concerns due to the unique advantages and broad application prospects. In this paper, the research results of the eight-element multiplexed fiber laser acoustic pressure array and the interrogation system are introduced, containing low-noise distributed feedback fiber laser (DFB-FL) fabrication, sensitivity enhancement packaging, and interferometric signal demodulation. The frequency response range of the system is 10Hz-10kHz, the laser frequency acoustic pressure sensitivity reaches 115 dB re Hz/Pa, and the equivalent noise acoustic pressure is less than 60μPa/Hz1/2. The dynamic range of the system is greater than 120 dB.
Miniature and low cost fiber Bragg grating interrogator for structural monitoring in nano-satellites
NASA Astrophysics Data System (ADS)
Toet, P. M.; Hagen, R. A. J.; Hakkesteegt, H. C.; Lugtenburg, J.; Maniscalco, M. P.
2017-11-01
In this paper we present a newly developed Fiber Optic measurement system, consisting of Fiber Bragg Grating (FBG) sensors and an FBG interrogator. The development of the measuring system is part of the PiezoElectric Assisted Smart Satellite Structure (PEASSS) project, which was initiated at the beginning of 2013 and is financed by the Seventh Framework Program (FP7) of the European Commission. Within the PEASSS project, a Nano-Satellite is being designed and manufactured to be equipped with new technology that will help keep Europe on the cutting edge of space research, potentially reducing the cost and development time for more accurate future sensor platforms including synthetic aperture optics, moving target detection and identification, and compact radars. After on ground testing the satellite is planned to be launched at the end of 2015. Within the satellite, different technologies will be demonstrated on orbit to show their capabilities for different in-space applications. For our application the FBG interrogator monitors the structural and thermal behaviour of a so called "smart panel". These panels will enable fine angle control and thermal and vibration compensation in order to improve all types of future Earth observations, such as environmental and planetary mapping, border and regional imaging. The Fiber Optic (FO) system in PEASSS includes four FBG strain sensors and two FBG temperature sensors. The 3 channel interrogator has to have a small footprint (110x50x40mm), is low cost, low in mass and has a low power consumption. In order to meet all these requirements, an interrogator has been designed based on a tunable Vertical-Cavity Surface-Emitting Laser (VCSEL) enabling a wavelength sweep of around 7 nm. To guarantee the absolute and relative performance, two reference methods are included internally in the interrogator. First, stabilized reference FBG sensors are used to obtain absolute wavelength calibrations. This method is used for the temperature sensors in the system, which will be measured with an accuracy of +/-1°C. Second, the strain sensors will be used to monitor deformation of piezo actuators (bimorph plates) in a way that temperature compensation is not required. Using FBGs on top and on the bottom of the plates, relative wavelength differences are measured. In order to have a high accuracy, inside the interrogator a fiber interferometer is used to track the wavelength change. Using this reference technology we are able to measure the (relative) wavelength difference between two FBGs well below 0.1pm.
Zhang, Yi-long; Liu, Le; Guo, Jun; Zhang, Peng-fei; Guo, Ji-hua; Ma, Hui; He, Yong-hong
2015-02-01
Surface plasmon resonance (SPR) sensors with spectral interrogation can adopt fiber to transmit light signals, thus leaving the sensing part separated, which is very convenient for miniaturization, remote-sensing and on-site analysis. Symmetrical optical waveguide (SOW) SPR has the same refractive index of the-two buffer media layers adjacent to the metal film, resulting in longer propagation distance, deeper penetration depth and better performance compared to conventional SPR In the present paper, we developed a symmetrical optical, waveguide (SOW) SPR sensor with wavelength interrogation. In the system, MgF2-Au-MgF2 film was used as SOW module for glucose sensing, and a fiber based light source and detection was used in the spectral interrogation. In the experiment, a refractive index resolution of 2.8 x 10(-7) RIU in fluid protocol was acquired. This technique provides advantages of high resolution and could have potential use in compact design, on-site analysis and remote sensing.
An improved ATAC-seq protocol reduces background and enables interrogation of frozen tissues.
Corces, M Ryan; Trevino, Alexandro E; Hamilton, Emily G; Greenside, Peyton G; Sinnott-Armstrong, Nicholas A; Vesuna, Sam; Satpathy, Ansuman T; Rubin, Adam J; Montine, Kathleen S; Wu, Beijing; Kathiria, Arwa; Cho, Seung Woo; Mumbach, Maxwell R; Carter, Ava C; Kasowski, Maya; Orloff, Lisa A; Risca, Viviana I; Kundaje, Anshul; Khavari, Paul A; Montine, Thomas J; Greenleaf, William J; Chang, Howard Y
2017-10-01
We present Omni-ATAC, an improved ATAC-seq protocol for chromatin accessibility profiling that works across multiple applications with substantial improvement of signal-to-background ratio and information content. The Omni-ATAC protocol generates chromatin accessibility profiles from archival frozen tissue samples and 50-μm sections, revealing the activities of disease-associated DNA elements in distinct human brain structures. The Omni-ATAC protocol enables the interrogation of personal regulomes in tissue context and translational studies.
Scaling beta-delayed neutron measurements to large detector areas
NASA Astrophysics Data System (ADS)
Sutanto, F.; Nattress, J.; Jovanovic, I.
2017-08-01
We explore the performance of a cargo screening system that consists of two large-sized composite scintillation detectors and a high-energy neutron interrogation source by modeling and simulation. The goal of the system is to measure β-delayed neutron emission from an illicit special nuclear material by use of active interrogation. This task is challenging because the β-delayed neutron yield is small in comparison with the yield of the prompt fission secondary products, β-delayed neutrons are emitted with relatively low energies, and high neutron and gamma backgrounds are typically present. Detectors used to measure delayed neutron emission must exhibit high intrinsic efficiency and cover a large solid angle, which also makes them sensitive to background neutron radiation. We present a case study where we attempt to detect the presence of 5 kg-scale quantities of 235U in a standard air-filled cargo container using 14 MeV neutrons as a probe. We find that by using a total measurement time of ˜11.6 s and a dose equivalent of ˜1.7 mrem, the presence of 235U can be detected with false positive and false negative probabilities that are both no larger than 0.1%.
Remotely-interrogated high data rate free space laser communications link
Ruggiero, Anthony J [Livermore, CA
2007-05-29
A system and method of remotely extracting information from a communications station by interrogation with a low power beam. Nonlinear phase conjugation of the low power beam results in a high power encoded return beam that automatically tracks the input beam and is corrected for atmospheric distortion. Intracavity nondegenerate four wave mixing is used in a broad area semiconductor laser in the communications station to produce the return beam.
ERIC Educational Resources Information Center
Py, Bernard
A progress report is presented of a study which applies a system of generative grammar to error analysis. The objective of the study was to reconstruct the grammar of students' interlanguage, using a systematic analysis of errors. (Interlanguage refers to the linguistic competence of a student who possesses a relatively systematic body of rules,…
Hettich, Robert L.; Pan, Chongle; Chourey, Karuna; Giannone, Richard J.
2013-01-01
Summary The availability of extensive genome information for many different microbes, including unculturable species in mixed communities from environmental samples, has enabled systems-biology interrogation by providing a means to access genomic, transcriptomic, and proteomic information. To this end, metaproteomics exploits the power of high performance mass spectrometry for extensive characterization of the complete suite of proteins expressed by a microbial community in an environmental sample. PMID:23469896
Fiber Bragg Grating Sensor System for Monitoring Smart Composite Aerospace Structures
NASA Technical Reports Server (NTRS)
Moslehi, Behzad; Black, Richard J.; Gowayed, Yasser
2012-01-01
Lightweight, electromagnetic interference (EMI) immune, fiber-optic, sensor- based structural health monitoring (SHM) will play an increasing role in aerospace structures ranging from aircraft wings to jet engine vanes. Fiber Bragg Grating (FBG) sensors for SHM include advanced signal processing, system and damage identification, and location and quantification algorithms. Potentially, the solution could be developed into an autonomous onboard system to inspect and perform non-destructive evaluation and SHM. A novel method has been developed to massively multiplex FBG sensors, supported by a parallel processing interrogator, which enables high sampling rates combined with highly distributed sensing (up to 96 sensors per system). The interrogation system comprises several subsystems. A broadband optical source subsystem (BOSS) and routing and interface module (RIM) send light from the interrogation system to a composite embedded FBG sensor matrix, which returns measurand-dependent wavelengths back to the interrogation system for measurement with subpicometer resolution. In particular, the returned wavelengths are channeled by the RIM to a photonic signal processing subsystem based on powerful optical chips, then passed through an optoelectronic interface to an analog post-detection electronics subsystem, digital post-detection electronics subsystem, and finally via a data interface to a computer. A range of composite structures has been fabricated with FBGs embedded. Stress tensile, bending, and dynamic strain tests were performed. The experimental work proved that the FBG sensors have a good level of accuracy in measuring the static response of the tested composite coupons (down to submicrostrain levels), the capability to detect and monitor dynamic loads, and the ability to detect defects in composites by a variety of methods including monitoring the decay time under different dynamic loading conditions. In addition to quasi-static and dynamic load monitoring, the system can capture acoustic emission events that can be a prelude to structural failure, as well as piezoactuator-induced ultrasonic Lamb-waves-based techniques as a basis for damage detection.
NASA Astrophysics Data System (ADS)
Deyglun, Clément; Carasco, Cédric; Pérot, Bertrand
2014-06-01
The detection of Special Nuclear Materials (SNM) by neutron interrogation is extensively studied by Monte Carlo simulation at the Nuclear Measurement Laboratory of CEA Cadarache (French Alternative Energies and Atomic Energy Commission). The active inspection system is based on the Associated Particle Technique (APT). Fissions induced by tagged neutrons (i.e. correlated to an alpha particle in the DT neutron generator) in SNM produce high multiplicity coincidences which are detected with fast plastic scintillators. At least three particles are detected in a short time window following the alpha detection, whereas nonnuclear materials mainly produce single events, or pairs due to (n,2n) and (n,n'γ) reactions. To study the performances of an industrial cargo container inspection system, Monte Carlo simulations are performed with the MCNP-PoliMi transport code, which records for each neutron history the relevant information: reaction types, position and time of interactions, energy deposits, secondary particles, etc. The output files are post-processed with a specific tool developed with ROOT data analysis software. Particles not correlated with an alpha particle (random background), counting statistics, and time-energy resolutions of the data acquisition system are taken into account in the numerical model. Various matrix compositions, suspicious items, SNM shielding and positions inside the container, are simulated to assess the performances and limitations of an industrial system.
Connolly, P.J.; Jezorek, I.G.; Martens, K.D.; Prentice, E.F.
2008-01-01
We tested the performance of two stationary interrogation systems designed for detecting the movement of fish with passive integrated transponder (PIT) tags. These systems allowed us to determine the direction of fish movement with high detection efficiency and high precision in a dynamic stream environment. We describe an indirect method for deriving an estimate for detection efficiency and the associated variance that does not rely on a known number of fish passing the system. By using six antennas arranged in a longitudinal series of three arrays, we attained detection efficiencies for downstream- and upstream-moving fish exceeding 96% during high-flow periods and approached 100% during low-flow periods for the two interrogation systems we tested. Because these systems did not rely on structural components, such as bridges or culverts, they were readily adaptable to remote, natural stream sites. Because of built-in redundancy, these systems were able to perform even with a loss of one or more antennas owing to dislodgement or electrical failure. However, the reduction in redundancy resulted in decreased efficiency and precision and the potential loss of ability to determine the direction of fish movement. What we learned about these systems should be applicable to a wide variety of other antenna configurations and to other types of PIT tags and transceivers.
Functional interrogation of non-coding DNA through CRISPR genome editing.
Canver, Matthew C; Bauer, Daniel E; Orkin, Stuart H
2017-05-15
Methodologies to interrogate non-coding regions have lagged behind coding regions despite comprising the vast majority of the genome. However, the rapid evolution of clustered regularly interspaced short palindromic repeats (CRISPR)-based genome editing has provided a multitude of novel techniques for laboratory investigation including significant contributions to the toolbox for studying non-coding DNA. CRISPR-mediated loss-of-function strategies rely on direct disruption of the underlying sequence or repression of transcription without modifying the targeted DNA sequence. CRISPR-mediated gain-of-function approaches similarly benefit from methods to alter the targeted sequence through integration of customized sequence into the genome as well as methods to activate transcription. Here we review CRISPR-based loss- and gain-of-function techniques for the interrogation of non-coding DNA. Copyright © 2017 Elsevier Inc. All rights reserved.
Methods and systems for Raman and optical cross-interrogation in flow-through silicon membranes
Bond, Tiziana C.; Letant, Sonia E.
2014-09-09
Cross-interrogating photonic detection systems and methods are shown. A flow through photonic crystal membrane with a surface enhanced Raman scattering (SERS) substrate is provided with pores which are distributed along multiple regions. The pores of one region have walls to which a first type of target specific anchor can be attached, while pores of another region have walls to which a second type of target specific anchor can be attached. An optical arrangement out-of-plane to the SERS substrate is also provided for enhanced sensitivity and identification of target organisms.
Ahmed, Imdad; Patel, Amisha S; Balgaard, Timothy J; Rosenfeld, Lynda E
2016-03-01
Interrogation/interpretation of cardiac implantable electronic devices (CIEDs) is frequently required in the emergency department (ED) or perioperative areas (OR) where resources to do this are often not available. CareLink Express (CLE; Medtronic, plc, Mounds View, MN, USA) is a technician-supported real-time remote interrogation system for Medtronic CIEDs. Using data from 136 US locations, this retrospective study was designed to assess CLE efficiency compared to traditional device management, and examine its findings. All 7,044 US CLE transmissions from the ED and OR (January 2012-October 2014) were compared to 217 traditional requests where CIED interrogations/interpretations were performed by calling industry representatives to these sites. CLE reduced the time to device interrogation/interpretation by 78%: 100 ± 140-22 ± 14 minutes, P < 0.0001, improving response time and consistency; ED: 82 ± 103-23 ± 18 minutes, P, ≤ 0.01; OR: 127 ± 181-17 ± 10 minutes, P < 0.0001. Actionable events (AE) (arrhythmia, device/lead abnormalities) were infrequent: 9.1% overall (ED: 9.9%; OR: 4.1%). Only 6.5% of patients with syncope/presyncope and 13.6% with a perceived shock had AE. AEs were more common in those with suspected device problems (30.4%) or audible alerts (52.6%). They were more likely in patients not enrolled in long-term remote monitoring (23.9% vs 8.2%, P < 0.0001) and in those with older CIED systems (7.4% in year 1 vs 31.0% after 10 years). The many patients with CIEDs, and the ability to quickly identify the minority with high-risk AE from the no/low-risk majority, strongly support CLE use in the ED and OR, sites which are expensive and prioritize efficiency. © 2015 Wiley Periodicals, Inc.
Combined Photoneutron And X Ray Interrogation Of Containers For Nuclear Materials
NASA Astrophysics Data System (ADS)
Gozani, Tsahi; Shaw, Timothy; King, Michael J.; Stevenson, John; Elsalim, Mashal; Brown, Craig; Condron, Cathie
2011-06-01
Effective cargo inspection systems for nuclear material detection require good penetration by the interrogating radiation, generation of a sufficient number of fissions, and strong and penetrating detection signatures. Inspection systems need also to be sensitive over a wide range of cargo types and densities encountered in daily commerce. Thus they need to be effective with highly hydrogenous cargo, where neutron attenuation is a major limitation, as well as with dense metallic cargo, where x-ray penetration is low. A system that interrogates cargo with both neutrons and x-rays can, in principle, achieve high performance over the widest range of cargos. Moreover, utilizing strong prompt-neutron (˜3 per fission) and delayed-gamma ray (˜7 per fission) signatures further strengthens the detection sensitivity across all cargo types. The complementary nature of x-rays and neutrons, used as both probing radiation and detection signatures, alleviates the need to employ exceedingly strong sources, which would otherwise be required to achieve adequate performance across all cargo types, if only one type of radiation probe were employed. A system based on the above principles, employing a commercially-available 9 MV linac was developed and designed. Neutrons are produced simultaneously with x-rays by the photonuclear interaction of the x-ray beam with a suitable converter. A total neutron yield on the order of 1011 n/s is achieved with an average electron beam current of 100 μA. If fissionable material is present, fissions are produced both by the high-energy x-ray beam and by the photoneutrons. Photofission and neutron fission dominate in hydrogenous and metallic cargos, respectively. Neutron-capture gamma rays provide information on the cargo composition. The prompt neutrons resulting from fission are detected by two independent detector systems: by very efficient Differential Die Away Analysis (DDAA) detectors, and by direct detection of neutrons with energies higher than 3 MeV using a recently developed fluorine-based threshold activation detector (TAD). The delayed gamma-ray signals are measured with high efficiency with the same TAD and with additional lower-cost plastic scintillators.
Okagbare, Paul I.; Soper, Steven A.
2011-01-01
Microfluidics represents a viable platform for performing High Throughput Screening (HTS) due to its ability to automate fluid handling and generate fluidic networks with high number densities over small footprints appropriate for the simultaneous optical interrogation of many screening assays. While most HTS campaigns depend on fluorescence, readers typically use point detection and serially address the assay results significantly lowering throughput or detection sensitivity due to a low duty cycle. To address this challenge, we present here the fabrication of a high density microfluidic network packed into the imaging area of a large field-of-view (FoV) ultrasensitive fluorescence detection system. The fluidic channels were 1, 5 or 10 μm (width), 1 μm (depth) with a pitch of 1–10 μm and each fluidic processor was individually addressable. The fluidic chip was produced from a molding tool using hot embossing and thermal fusion bonding to enclose the fluidic channels. A 40X microscope objective (numerical aperture = 0.75) created a FoV of 200 μm, providing the ability to interrogate ~25 channels using the current fluidic configuration. An ultrasensitive fluorescence detection system with a large FoV was used to transduce fluorescence signals simultaneously from each fluidic processor onto the active area of an electron multiplying charge-coupled device (EMCCD). The utility of these multichannel networks for HTS was demonstrated by carrying out the high throughput monitoring of the activity of an enzyme, APE1, used as a model screening assay. PMID:20872611
ERIC Educational Resources Information Center
Westberry, Nicola; Franken, Margaret
2015-01-01
This paper provides an Activity Theory analysis of two online student-driven interactive learning activities to interrogate assumptions that such groups can effectively learn in the absence of the teacher. Such an analysis conceptualises learning tasks as constructed objects that drive pedagogical activity. The analysis shows a disconnect between…
Bicket, Mark C; Hanna, George M
2016-02-01
Intrathecal drug delivery systems represent an increasingly common treatment modality for patients with a variety of conditions, including chronic pain and spasticity. Pumps rely on electronic programming to properly control and administer highly concentrated medications. Electromagnetic interference (EMI) is a known exposure that may cause a potential patient safety issue stemming from direct patient injury, pump damage, or changes to pump operation or flow rate. The objective of our case report was to describe an approach to evaluating a patient with a pump prior to and following exposure to EMI from electroconvulsive therapy (ECT), as well as to document findings from device interrogations associated with this event. Case report. Academic university-based pain management center. We present the case of a patient with an intrathecal pump who underwent multiple exposures to EMI in the form of 42 ECT sessions. Interrogation of the intrathecal drug delivery system revealed no safety issues following ECT sessions. At no time were error messages, unintentional changes in event logs, unintentional changes in pump settings, or evidence of pump stall or over-infusion noted. Communication with multiple entities (patient, family, consulting physicians, and device manufacturer) and maintaining vigilance through device interrogation both before and after EMI exposure are appropriate safeguards to mitigate the risk and detect potential adverse events of EMI with intrathecal drug delivery systems. Given the infrequent reports of device exposure to ECT, best practices may be derived from experience with EMI exposure from magnetic resonance imaging (MRI). Although routine EMI exposure to intrathecal drug delivery systems should be avoided, we describe one patient with repeated exposure to ECT without apparent complication.
Cleary, Hayley M D
2014-06-01
Although empirical attention to police interrogation has gained traction in recent years, comparatively few studies have examined interrogation of juvenile suspects, and virtually none have examined actual interrogations. Despite a growing literature on youths' interrogation-related capacities, we still know very little about what actually transpires when police question youth. The present study examines electronically recorded police interviews with juveniles to describe the characteristics, processes, and outcomes that occur in actual juvenile interrogations, including interview duration, individuals present, and confessions. Fifty-seven electronic recordings from 17 police departments were analyzed using observational research software. The median juvenile interrogation lasted 46 min, though the range was extensive (6 min to nearly 5 hr). Youth frequently submitted to questioning without a parent or advocate present, and disruptions to the interview process were common. Interrogation outcomes varied and included full confessions, partially incriminating admissions, and denials of guilt. Results from this study provide context for interrogation research using other methods and suggest that youth may frequently consent to interrogation in the absence of important legal protections.
Optimal sensor placement for active guided wave interrogation of complex metallic components
NASA Astrophysics Data System (ADS)
Coelho, Clyde K.; Kim, Seung Bum; Chattopadhyay, Aditi
2011-04-01
With research in structural health monitoring (SHM) moving towards increasingly complex structures for damage interrogation, the placement of sensors is becoming a key issue in the performance of the damage detection methodologies. For ultrasonic wave based approaches, this is especially important because of the sensitivity of the travelling Lamb waves to material properties, geometry and boundary conditions that may obscure the presence of damage if they are not taken into account during sensor placement. The framework proposed in this paper defines a sensing region for a pair of piezoelectric transducers in a pitch-catch damage detection approach by taking into account the material attenuation and probability of false alarm. Using information about the region interrogated by a sensoractuator pair, a simulated annealing optimization framework was implemented in order to place sensors on complex metallic geometries such that a selected minimum damage type and size could be detected with an acceptable probability of false alarm anywhere on the structure. This approach was demonstrated on a lug joint to detect a crack and on a large Naval SHM test bed and resulted in a placement of sensors that was able to interrogate all parts of the structure using the minimum number of transducers.
Performance of an optical identification and interrogation system
NASA Astrophysics Data System (ADS)
Venugopalan, A.; Ghosh, A. K.; Verma, P.; Cheng, S.
2008-04-01
A free space optics based identification and interrogation system has been designed. The applications of the proposed system lie primarily in areas which require a secure means of mutual identification and information exchange between optical readers and tags. Conventional RFIDs raise issues regarding security threats, electromagnetic interference and health safety. The security of RF-ID chips is low due to the wide spatial spread of radio waves. Malicious nodes can read data being transmitted on the network, if they are in the receiving range. The proposed system provides an alternative which utilizes the narrow paraxial beams of lasers and an RSA-based authentication scheme. These provide enhanced security to communication between a tag and the base station or reader. The optical reader can also perform remote identification and the tag can be read from a far off distance, given line of sight. The free space optical identification and interrogation system can be used for inventory management, security systems at airports, port security, communication with high security systems, etc. to name a few. The proposed system was implemented with low-cost, off-the-shelf components and its performance in terms of throughput and bit error rate has been measured and analyzed. The range of operation with a bit-error-rate lower than 10-9 was measured to be about 4.5 m. The security of the system is based on the strengths of the RSA encryption scheme implemented using more than 1024 bits.
Asian American Student Engagement in Student Leadership and Activism
ERIC Educational Resources Information Center
Manzano, Lester J.; Poon, OiYan A.; Na, Vanessa S.
2017-01-01
Conceptual models for understanding the ways in which Asian American students engage in leadership and activism are interrogated. The chapter provides a discussion of implications for student affairs professionals working with Asian American student leaders and activists.
TDM interrogation of intensity-modulated USFBGs network based on multichannel lasers.
Rohollahnejad, Jalal; Xia, Li; Cheng, Rui; Ran, Yanli; Rahubadde, Udaya; Zhou, Jiaao; Zhu, Lin
2017-01-23
We report a large-scale multi-channel fiber sensing network, where ultra-short FBGs (USFBGs) instead of conventional narrow-band ultra-weak FBGs are used as the sensors. In the time division multiplexing scheme of the network, each grating response is resolved as three adjacent discrete peaks. The central wavelengths of USFBGs are tracked with the differential detection, which is achieved by calculating the peak-to-peak ratio of two maximum peaks. Compared with previous large-scale hybrid multiplexing sensing networks (e.g., WDM/TDM) which typically have relatively low interrogation speed and very high complexity, the proposed system can achieve interrogation of all channel sensors through very fast and simple intensity measurements with a broad dynamic range. A proof-of-concept experiment with twenty USFBGs, at two wavelength channels, was performed and a fast static strain measurements were demonstrated, with a high average sensitivity of ~0.54dB/µƐ and wide dynamic range of over ~3000µƐ. The channel to channel switching time was 10ms and total network interrogation time was 50ms.
Concept and Design of the Hybrid Sensor Bus System for Telecommunication Satellites
NASA Astrophysics Data System (ADS)
Hurni, Andreas; Tiefenbeck, Christoph; Manhart, Markus; Heyer, Heinz-Volker; Plattner, Markus; Putzer, Philipp; Roßner, Max; Koch, Alexander W.; Furano, Gianluca; McKenzie, Iain; Lam, King
2012-08-01
The Hybrid Sensor Bus (HSB) is a system for sensor interrogation in telecommunication satellites, which will be developed in the frame of the ESA ARTES program. The main target of the HSB system is the replacement of classical point-to-point wired sensors by sensors connected on bus networks. This will save mass and reduces efforts in assembly, integration and testing (AIT). The HSB system is able to manage an electrical I2C and a fiber-optical sensor network. The system consists of an intelligent power module, an electrical and a fiber-optical interrogator module in cold redundancy. Additional features of the HSB system are its modularity and the adaptability to different satellite platforms. The implementation of a HSB system allows platform manufacturers to build a more cost efficient satellite.This paper presents the concept and the design status of the HSB system.
29 CFR 18.614 - Calling and interrogation of witnesses by judge.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 29 Labor 1 2013-07-01 2013-07-01 false Calling and interrogation of witnesses by judge. 18.614... interrogation of witnesses by judge. (a) Calling by the judge. The judge may, on the judge's own motion or at... thus called. (b) Interrogation by the judge. The judge may interrogate witnesses, whether called by the...
29 CFR 18.614 - Calling and interrogation of witnesses by judge.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 29 Labor 1 2010-07-01 2010-07-01 true Calling and interrogation of witnesses by judge. 18.614... interrogation of witnesses by judge. (a) Calling by the judge. The judge may, on the judge's own motion or at... thus called. (b) Interrogation by the judge. The judge may interrogate witnesses, whether called by the...
29 CFR 18.614 - Calling and interrogation of witnesses by judge.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 29 Labor 1 2014-07-01 2013-07-01 true Calling and interrogation of witnesses by judge. 18.614... interrogation of witnesses by judge. (a) Calling by the judge. The judge may, on the judge's own motion or at... thus called. (b) Interrogation by the judge. The judge may interrogate witnesses, whether called by the...
29 CFR 18.614 - Calling and interrogation of witnesses by judge.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 29 Labor 1 2012-07-01 2012-07-01 false Calling and interrogation of witnesses by judge. 18.614... interrogation of witnesses by judge. (a) Calling by the judge. The judge may, on the judge's own motion or at... thus called. (b) Interrogation by the judge. The judge may interrogate witnesses, whether called by the...
29 CFR 18.614 - Calling and interrogation of witnesses by judge.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 29 Labor 1 2011-07-01 2011-07-01 false Calling and interrogation of witnesses by judge. 18.614... interrogation of witnesses by judge. (a) Calling by the judge. The judge may, on the judge's own motion or at... thus called. (b) Interrogation by the judge. The judge may interrogate witnesses, whether called by the...
Novel remote sensor systems: design, prototyping, and characterization
NASA Astrophysics Data System (ADS)
Kayastha, V.; Gibbons, S.; Lamb, J. E.; Giedd, R. E.
2014-06-01
We have designed and tested a prototype TRL4 radio-frequency (RF) sensing platform containing a transceiver that interrogates a passive carbon nanotube (CNT)-based sensor platform. The transceiver can be interfaced to a server technology such as a Bluetooth® or Wi-Fi device for further connectivity. The novelty of a very-low-frequency (VLF) implementation in the transceiver design will ultimately enable deep penetration into the ground or metal structures to communicate with buried sensing platforms. The sensor platform generally consists of printed electronic devices made of CNTs on flexible poly(ethylene terephthalate) (PET) and Kapton® substrates. This novel remote sensing system can be integrated with both passive and active sensing platforms. It offers unique characteristics suitable for a variety of sensing applications. The proposed sensing platforms can take on different form factors and the RF output of the sensing platforms could be modulated by humidity, temperature, pressure, strain, or vibration signals. Resonant structures were designed and constructed to operate in the very-high-frequency (VHF) and VLF ranges. In this presentation, we will report results of our continued effort to develop a commercially viable transceiver capable of interrogating the conformally mounted sensing platforms made from CNTs or silver-based nanomaterials on polyimide substrates over a broad range of frequencies. The overall performance of the sensing system with different sensing elements and at different frequency ranges will be discussed.
Topics in computational physics
NASA Astrophysics Data System (ADS)
Monville, Maura Edelweiss
Computational Physics spans a broad range of applied fields extending beyond the border of traditional physics tracks. Demonstrated flexibility and capability to switch to a new project, and pick up the basics of the new field quickly, are among the essential requirements for a computational physicist. In line with the above mentioned prerequisites, my thesis described the development and results of two computational projects belonging to two different applied science areas. The first project is a Materials Science application. It is a prescription for an innovative nano-fabrication technique that is built out of two other known techniques. The preliminary results of the simulation of this novel nano-patterning fabrication method show an average improvement, roughly equal to 18%, with respect to the single techniques it draws on. The second project is a Homeland Security application aimed at preventing smuggling of nuclear material at ports of entry. It is concerned with a simulation of an active material interrogation system based on the analysis of induced photo-nuclear reactions. This project consists of a preliminary evaluation of the photo-fission implementation in the more robust radiation transport Monte Carlo codes, followed by the customization and extension of MCNPX, a Monte Carlo code developed in Los Alamos National Laboratory, and MCNP-PoliMi. The final stage of the project consists of testing the interrogation system against some real world scenarios, for the purpose of determining the system's reliability, material discrimination power, and limitations.
High data-rate atom interferometers through high recapture efficiency
Biedermann, Grant; Rakholia, Akash Vrijal; McGuinness, Hayden
2015-01-27
An inertial sensing system includes a magneto-optical trap (MOT) that traps atoms within a specified trapping region. The system also includes a cooling laser that cools the trapped atoms so that the atoms remain within the specified region for a specified amount of time. The system further includes a light-pulse atom interferometer (LPAI) that performs an interferometric interrogation of the atoms to determine phase changes in the atoms. The system includes a controller that controls the timing of MOT and cooling laser operations, and controls the timing of interferometric operations to substantially recapture the atoms in the specified trapping region. The system includes a processor that determines the amount inertial movement of the inertial sensing system based on the determined phase changes in the atoms. Also, a method of inertial sensing using this inertial sensing system includes recapture of atoms within the MOT following interferometric interrogation by the LPAI.
Metabolic interrogation as a tool to optimize chemotherapeutic regimens.
Sandulache, Vlad C; Chen, Yunyun; Feng, Lei; William, William N; Skinner, Heath D; Myers, Jeffrey N; Meyn, Raymond E; Li, Jinzhong; Mijiti, Ainiwaer; Bankson, James A; Fuller, Clifton D; Konopleva, Marina Y; Lai, Stephen Y
2017-03-14
Platinum-based (Pt) chemotherapy is broadly utilized in the treatment of cancer. Development of more effective, personalized treatment strategies require identification of novel biomarkers of treatment response. Since Pt compounds are inactivated through cellular metabolic activity, we hypothesized that metabolic interrogation can predict the effectiveness of Pt chemotherapy in a pre-clinical model of head and neck squamous cell carcinoma (HNSCC).We tested the effects of cisplatin (CDDP) and carboplatin (CBP) on DNA damage, activation of cellular death cascades and tumor cell metabolism, specifically lactate production. Pt compounds induced an acute dose-dependent, transient drop in lactate generation in vitro, which correlated with effects on DNA damage and cell death. Neutralization of free radical stress abrogated these effects. The magnitude of this effect on lactate production correlated with the differential sensitivity of HNSCC cells to Pt compounds (CDDP vs CBP) and p53-driven Pt chemotherapy resistance. Using dual flank xenograft tumors, we demonstrated that Pt-driven effects on lactate levels correlate with effects on tumor growth delay in a dose-dependent manner and that lactate levels can define the temporal profile of Pt chemotherapy-induced metabolic stress. Lactate interrogation also predicted doxorubicin effects on cell death in both solid tumor (HNSCC) and acute myelogenous leukemia (AML) cell lines.Real-time metabolic interrogation of acute changes in cell and tumor lactate levels reflects chemotherapy effects on DNA damage, cell death and tumor growth delay. We have identified a real-time biomarker of chemotherapy effectiveness which can be used to develop adaptive, iterative and personalized treatment regimens against a variety of solid and hematopoietic malignancies.
Metabolic interrogation as a tool to optimize chemotherapeutic regimens
Feng, Lei; William, William N.; Skinner, Heath D.; Myers, Jeffrey N.; Meyn, Raymond E.; Li, Jinzhong; Mijiti, Ainiwaer; Bankson, James A.; Fuller, Clifton D.; Konopleva, Marina Y.; Lai, Stephen Y.
2017-01-01
Platinum-based (Pt) chemotherapy is broadly utilized in the treatment of cancer. Development of more effective, personalized treatment strategies require identification of novel biomarkers of treatment response. Since Pt compounds are inactivated through cellular metabolic activity, we hypothesized that metabolic interrogation can predict the effectiveness of Pt chemotherapy in a pre-clinical model of head and neck squamous cell carcinoma (HNSCC). We tested the effects of cisplatin (CDDP) and carboplatin (CBP) on DNA damage, activation of cellular death cascades and tumor cell metabolism, specifically lactate production. Pt compounds induced an acute dose-dependent, transient drop in lactate generation in vitro, which correlated with effects on DNA damage and cell death. Neutralization of free radical stress abrogated these effects. The magnitude of this effect on lactate production correlated with the differential sensitivity of HNSCC cells to Pt compounds (CDDP vs CBP) and p53-driven Pt chemotherapy resistance. Using dual flank xenograft tumors, we demonstrated that Pt-driven effects on lactate levels correlate with effects on tumor growth delay in a dose-dependent manner and that lactate levels can define the temporal profile of Pt chemotherapy-induced metabolic stress. Lactate interrogation also predicted doxorubicin effects on cell death in both solid tumor (HNSCC) and acute myelogenous leukemia (AML) cell lines. Real-time metabolic interrogation of acute changes in cell and tumor lactate levels reflects chemotherapy effects on DNA damage, cell death and tumor growth delay. We have identified a real-time biomarker of chemotherapy effectiveness which can be used to develop adaptive, iterative and personalized treatment regimens against a variety of solid and hematopoietic malignancies. PMID:28184025
Magneto-Optic Field Coupling in Optical Fiber Bragg Gratings
NASA Technical Reports Server (NTRS)
Carman, Gregory P. (Inventor); Mohanchandra, Panduranga K. (Inventor); Emmons, Michael C. (Inventor); Richards, William Lance (Inventor)
2016-01-01
The invention is a magneto-optic coupled magnetic sensor that comprises a standard optical fiber Bragg grating system. The system includes an optical fiber with at least one Bragg grating therein. The optical fiber has at least an inner core and a cladding that surrounds the inner core. The optical fiber is part of an optical system that includes an interrogation device that provides a light wave through the optical fiber and a system to determine the change in the index of refraction of the optical fiber. The cladding of the optical fiber comprises at least a portion of which is made up of ferromagnetic particles so that the ferromagnetic particles are subject to the light wave provided by the interrogation system. When a magnetic field is present, the ferromagnetic particles change the optical properties of the sensor directly.
NASA Astrophysics Data System (ADS)
Li, Jiangyu; Huang, Boyuan; Nasr Esfahani, Ehsan; Wei, Linlin; Yao, Jianjun; Zhao, Jinjin; Chen, Wei
2017-10-01
Halide perovskite solar cells based on CH3NH3PbI3 and related materials have emerged as the most exciting development in the next generation photovoltaic technologies, yet the microscopic phenomena involving photo-carriers, ionic defects, spontaneous polarization, and molecular vibration and rotation interacting with numerous grains, grain boundaries, and interfaces are still inadequately understood. In fact, there is still need for an effective method to interrogate the local photovoltaic properties of halide perovskite solar cells that can be directly traced to their microstructures on one hand and linked to their device performance on the other hand. In this perspective, we propose that scanning probe microscopy (SPM) techniques have great potential to realize such promises at the nanoscale, and highlight some of the recent progresses and challenges along this line of investigation toward local probing of photocurrent, work function, ionic activities, polarization switching, and chemical degradation. We also emphasize the importance of multi-modality imaging, in-operando scanning, big data analysis, and multidisciplinary collaboration for further studies toward fully understanding of these complex systems.
Nuclear Resonance Fluorescence Measurements on ^237Np for Security and Safeguards Applications
NASA Astrophysics Data System (ADS)
Angell, C. T.; Joshi, T.; Yee, Ryan; Norman, E. B.; Kulp, W. D.; Warren, G. A.; Korbly, S.; Klimenko, A.; Wilson, C.; Copping, R.; Shuh, D. K.
2009-10-01
The smuggling of nuclear material and the diversion of fissile material for covert weapon programs both present grave risks to world security. Methods are needed to detect nuclear material smuggled in cargo, and for proper material accountability in civilian fuel re-processing facilities. Nuclear resonance fluorescence (NRF) is a technique that can address both needs. It is a non-destructive active interrogation method that provides isotope-specific information. It works by using a γ-ray beam to resonantly excite levels in a nucleus and observing the γ-rays emitted whose energy and intensity are characteristic of that isotope. ^237Np presents significant safeguard challenges; it is fissile yet currently has fewer safeguard restrictions. NRF measurements on ^237Np will expand the nuclear database and will permit designing interrogation and assay systems. Measurements were made using the bremsstrahlung beam at the HVRL at MIT on a 7 g target of ^237Np with two incident electron energies of 2.8 and 3.1 MeV. Results will be presented with discussion of the relevant nuclear structure necessary to predict levels in other actinides.
Jezorek, Ian G.; Connolly, Patrick J.
2012-01-01
An additional USGS-CRRL task, under contract number 50150, was to build three antennas for use with Destron-Fearing 2001F-ISO PIT tag readers. These antennas would be 5 used at the East Fork Hood River Acclimation site. They would be placed in the outflow channel to inform managers about the number of PIT tagged steelhead smolts released to the Hood River after a period of acclimation when some mortality and predation might occur.
John, Nigel W; McCloy, Rory F; Herrman, Simone
2004-01-01
The Op3D visualization system allows, for the first time, a surgeon in the operating theatre to interrogate patient-specific medical data sets rendered in three dimensions using high-performance computing. The hypothesis of this research is that the success rate of hepato-pancreatic surgical resections can be improved by replacing the light box with an interactive 3D representation of the medical data in the operating theatre. A laptop serves as the client computer and an easy-to-use interface has been developed for the surgeon to interact with and interrogate the patient data. To date, 16 patients have had 3D reconstructions of their DICOM data sets, including preoperative interrogation and planning of surgery. Interrogation of the 3D images live in theatre and comparison with the surgeons' operative findings (including intraoperative ultrasound) led to the operation being abandoned in 25% of cases, adoption of an alternative surgical approach in 25% of cases, and helpful image guidance for successful resection in 50% of cases. The clinical value of the latest generation of scanners and digital imaging techniques cannot be realized unless appropriate dissemination of the images takes place. This project has succeeded in translating the image technology into a user-friendly form and delivers 3D reconstructions of patient-specific data to the "sharp end"-the surgeon undertaking the tumor resection in theatre, in a manner that allows interaction and interpretation. More time interrogating the 3D data sets preoperatively would help reduce the incidence of abandoned operations-this is part of the surgeons' learning curve. We have developed one of the first practical applications to benefit from remote visualization, and certainly the first medical visualization application of this kind.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Church, J; Slaughter, D; Norman, E
Error rates in a cargo screening system such as the Nuclear Car Wash [1-7] depend on the standard deviation of the background radiation count rate. Because the Nuclear Car Wash is an active interrogation technique, the radiation signal for fissile material must be detected above a background count rate consisting of cosmic, ambient, and neutron-activated radiations. It was suggested previously [1,6] that the Corresponding negative repercussions for the sensitivity of the system were shown. Therefore, to assure the most accurate estimation of the variation, experiments have been performed to quantify components of the actual variance in the background count rate,more » including variations in generator power, irradiation time, and container contents. The background variance is determined by these experiments to be a factor of 2 smaller than values assumed in previous analyses, resulting in substantially improved projections of system performance for the Nuclear Car Wash.« less
Wavelength interrogation of fiber Bragg grating sensors based on crossed optical Gaussian filters.
Cheng, Rui; Xia, Li; Zhou, Jiaao; Liu, Deming
2015-04-15
Conventional intensity-modulated measurements require to be operated in linear range of filter or interferometric response to ensure a linear detection. Here, we present a wavelength interrogation system for fiber Bragg grating sensors where the linear transition is achieved with crossed Gaussian transmissions. This unique filtering characteristic makes the responses of the two branch detections follow Gaussian functions with the same parameters except for a delay. The substraction of these two delayed Gaussian responses (in dB) ultimately leads to a linear behavior, which is exploited for the sensor wavelength determination. Beside its flexibility and inherently power insensitivity, the proposal also shows a potential of a much wider operational range. Interrogation of a strain-tuned grating was accomplished, with a wide sensitivity tuning range from 2.56 to 8.7 dB/nm achieved.
Lazar, Vladimir; Martini, Jean-François; Gomez-Navarro, Jesus; Yver, Antoine; Kan, Zhengyin; Dry, Jonathan R.; Kehren, Jeanne; Validire, Pierre; Rodon, Jordi; Vielh, Philippe; Ducreux, Michel; Galbraith, Susan; Lehnert, Manfred; Onn, Amir; Berger, Raanan; Pierotti, Marco A.; Porgador, Angel; Pramesh, CS; Ye, Ding-wei; Carvalho, Andre L.; Batist, Gerald; Le Chevalier, Thierry; Morice, Philippe; Besse, Benjamin; Vassal, Gilles; Mortlock, Andrew; Hansson, Johan; Berindan-Neagoe, Ioana; Dann, Robert; Haspel, Joel; Irimie, Alexandru; Laderman, Steve; Nechushtan, Hovav; Al Omari, Amal S.; Haywood, Trent; Bresson, Catherine; Soo, Khee Chee; Osman, Iman; Mata, Hilario; Lee, Jack J.; Jhaveri, Komal; Meurice, Guillaume; Palmer, Gary; Lacroix, Ludovic; Koscielny, Serge; Eterovic, Karina Agda; Blay, Jean-Yves; Buller, Richard; Eggermont, Alexander; Schilsky, Richard L.; Mendelsohn, John; Soria, Jean-Charles; Rothenberg, Mace
2015-01-01
Non-small cell lung cancer (NSCLC) is a leading cause of death worldwide. Targeted monotherapies produce high regression rates, albeit for limited patient subgroups, who inevitably succumb. We present a novel strategy for identifying customized combinations of triplets of targeted agents, utilizing a simplified interventional mapping system (SIMS) that merges knowledge about existent drugs and their impact on the hallmarks of cancer. Based on interrogation of matched lung tumor and normal tissue using targeted genomic sequencing, copy number variation, transcriptomics, and miRNA expression, the activation status of 24 interventional nodes was elucidated. An algorithm was developed to create a scoring system that enables ranking of the activated interventional nodes for each patient. Based on the trends of co-activation at interventional points, combinations of drug triplets were defined in order to overcome resistance. This methodology will inform a prospective trial to be conducted by the WIN consortium, aiming to significantly impact survival in metastatic NSCLC and other malignancies. PMID:25944621
Polymerase chain reaction system
Benett, William J.; Richards, James B.; Stratton, Paul L.; Hadley, Dean R.; Milanovich, Fred P.; Belgrader, Phil; Meyer, Peter L.
2004-03-02
A portable polymerase chain reaction DNA amplification and detection system includes one or more chamber modules. Each module supports a duplex assay of a biological sample. Each module has two parallel interrogation ports with a linear optical system. The system is capable of being handheld.
Digitally controlled chirped pulse laser for sub-terahertz-range fiber structure interrogation.
Chen, Zhen; Hefferman, Gerald; Wei, Tao
2017-03-01
This Letter reports a sweep velocity-locked laser pulse generator controlled using a digital phase-locked loop (DPLL) circuit. This design is used for the interrogation of sub-terahertz-range fiber structures for sensing applications that require real-time data collection with millimeter-level spatial resolution. A distributed feedback laser was employed to generate chirped laser pulses via injection current modulation. A DPLL circuit was developed to lock the optical frequency sweep velocity. A high-quality linearly chirped laser pulse with a frequency excursion of 117.69 GHz at an optical communication band was demonstrated. The system was further adopted to interrogate a continuously distributed sub-terahertz-range fiber structure (sub-THz-fs) for sensing applications. A strain test was conducted in which the sub-THz-fs showed a linear response to longitudinal strain change with predicted sensitivity. Additionally, temperature testing was conducted in which a heat source was used to generate a temperature distribution along the fiber structure to demonstrate its distributed sensing capability. A Gaussian temperature profile was measured using the described system and tracked in real time, as the heat source was moved.
Wavelength-switched phase interrogator for extrinsic Fabry-Perot interferometric sensors.
Xia, Ji; Xiong, Shuidong; Wang, Fuyin; Luo, Hong
2016-07-01
We report on phase interrogation of extrinsic Fabry-Perot interferometric (EFPI) sensors through a wavelength-switched unit with a polarization-maintaining fiber Bragg grating (PMFBG). The measurements at two wavelengths are first achieved in one total-optical path. The reflected peaks of the PMFBG with two natural wavelengths are in mutually perpendicular polarization detection, and they are switched through an electro-optic modulator at a high switching speed of 10 kHz. An ellipse fitting differential cross multiplication (EF-DCM) algorithm is proposed for interrogating the variation of the gap length of the EFPI sensors. The phase demodulation system has been demonstrated to recover a minimum phase of 0.42 μrad/Hz at the test frequency of 100 Hz with a stable intensity fluctuation level of ±0.8 dB. Three EFPI sensors with different cavity lengths are tested at the test frequency of 200 Hz, and the results indicate that the system can achieve the demodulation of EFPI sensors with different cavity lengths stably.
Space Gator: a giant leap for fiber optic sensing
NASA Astrophysics Data System (ADS)
Evenblij, R. S.; Leijtens, J. A. P.
2017-11-01
Fibre Optic Sensing is a rapidly growing application field for Photonics Integrated Circuits (PIC) technology. PIC technology is regarded enabling for required performances and miniaturization of next generation fibre optic sensing instrumentation. So far a number of Application Specific Photonics Integrated Circuits (ASPIC) based interrogator systems have been realized as operational system-on-chip devices. These circuits have shown that all basic building blocks are working and complete interrogator on chip solutions can be produced. Within the Saristu (FP7) project several high reliability solutions for fibre optic sensing in Aeronautics are being developed, combining the specifically required performance aspects for the different sensing applications: damage detection, impact detection, load monitoring and shape sensing (including redundancy aspects and time division features). Further developments based on devices and taking into account specific space requirements (like radiation aspects) will lead to the Space Gator, which is a radiation tolerant highly integrated Fibre Bragg Grating (FBG) interrogator on chip. Once developed and qualified the Space Gator will be a giant leap for fibre optic sensing in future space applications.
A pilot study of implantable cardiac device interrogation by emergency department personnel.
Neuenschwander, James F; Hiestand, Brian C; Peacock, W Frank; Billings, John M; Sondrup, Cole; Hummel, John D; Abraham, William T
2014-03-01
Implanted devices (eg, pacemakers and defibrillators) provide valuable information and may be interrogated to obtain diagnostic information and to direct management. During admission to an emergency department (ED), significant time and cost are spent waiting for device manufacturer representatives or cardiologists to access the data. If ED personnel could safely interrogate implanted devices, more rapid disposition could occur, thus leading to potentially better outcomes at a reduced cost. This was a pilot study examining the feasibility of ED device interrogation. This was a prospective convenience sample study of patients presenting to the ED with any chief complaint and who had an implantable device capable of being interrogated by a Medtronic reader. After obtaining informed consent, study patients underwent device interrogation by ED research personnel. After reviewing the device data, the physician documented their opinions of the value of data in aiding care. Patients were followed up at intervals ranging from 30 days out to 1 year to determine adverse events relating to interrogation. Forty-four patients underwent device interrogation. Their mean age was 56 ± 14.7 years (range, 28-83), 75% (33/44) were male and 75% (33/44) were hospitalized from the ED. The interrogations took less than 10 minutes 89% of the time. In 60% of the cases, ED physicians reported the data-assisted patient care. No adverse events were reported relating to the ED interrogations. In this pilot study, we found that ED personnel can safely and quickly interrogate implantable devices to obtain potentially useful clinical data.
Code of Federal Regulations, 2013 CFR
2013-10-01
... advisors to interrogators, in interrogations of detainees if— (1) Such personnel are subject to the same...); and DoD Directive 3115.09, DoD Intelligence Interrogations, Detainee Debriefings, and Tactical... and interrogations as those that apply to Government personnel in such positions in such...
Code of Federal Regulations, 2012 CFR
2012-10-01
... advisors to interrogators, in interrogations of detainees if— (1) Such personnel are subject to the same...); and DoD Directive 3115.09, DoD Intelligence Interrogations, Detainee Debriefings, and Tactical... and interrogations as those that apply to Government personnel in such positions in such...
Code of Federal Regulations, 2011 CFR
2011-10-01
... advisors to interrogators, in interrogations of detainees if— (1) Such personnel are subject to the same...); and DoD Directive 3115.09, DoD Intelligence Interrogations, Detainee Debriefings, and Tactical... and interrogations as those that apply to Government personnel in such positions in such...
Code of Federal Regulations, 2014 CFR
2014-10-01
... advisors to interrogators, in interrogations of detainees if— (1) Such personnel are subject to the same...); and DoD Directive 3115.09, DoD Intelligence Interrogations, Detainee Debriefings, and Tactical... and interrogations as those that apply to Government personnel in such positions in such...
Beyond editing: repurposing CRISPR-Cas9 for precision genome regulation and interrogation.
Dominguez, Antonia A; Lim, Wendell A; Qi, Lei S
2016-01-01
The bacterial CRISPR-Cas9 system has emerged as a multifunctional platform for sequence-specific regulation of gene expression. This Review describes the development of technologies based on nuclease-deactivated Cas9, termed dCas9, for RNA-guided genomic transcription regulation, both by repression through CRISPR interference (CRISPRi) and by activation through CRISPR activation (CRISPRa). We highlight different uses in diverse organisms, including bacterial and eukaryotic cells, and summarize current applications of harnessing CRISPR-dCas9 for multiplexed, inducible gene regulation, genome-wide screens and cell fate engineering. We also provide a perspective on future developments of the technology and its applications in biomedical research and clinical studies.
Beyond editing: repurposing CRISPR–Cas9 for precision genome regulation and interrogation
Dominguez, Antonia A.; Lim, Wendell A.; Qi, Lei S.
2016-01-01
The bacterial CRISPR–Cas9 system has emerged as a multifunctional platform for sequence-specific regulation of gene expression. This Review describes the development of technologies based on nuclease-deactivated Cas9, termed dCas9, for RNA-guided genomic transcription regulation, both by repression through CRISPR interference (CRISPRi) and by activation through CRISPR activation (CRISPRa). We highlight different uses in diverse organisms, including bacterial and eukaryotic cells, and summarize current applications of harnessing CRISPR–dCas9 for multiplexed, inducible gene regulation, genome-wide screens and cell fate engineering. We also provide a perspective on future developments of the technology and its applications in biomedical research and clinical studies. PMID:26670017
Smithard, Joel; Rajic, Nik; van der Velden, Stephen; Norman, Patrick; Rosalie, Cedric; Galea, Steve; Mei, Hanfei; Lin, Bin; Giurgiutiu, Victor
2017-07-20
A key longstanding objective of the Structural Health Monitoring (SHM) research community is to enable the embedment of SHM systems in high value assets like aircraft to provide on-demand damage detection and evaluation. As against traditional non-destructive inspection hardware, embedded SHM systems must be compact, lightweight, low-power and sufficiently robust to survive exposure to severe in-flight operating conditions. Typical Commercial-Off-The-Shelf (COTS) systems can be bulky, costly and are often inflexible in their configuration and/or scalability, which militates against in-service deployment. Advances in electronics have resulted in ever smaller, cheaper and more reliable components that facilitate the development of compact and robust embedded SHM systems, including for Acousto-Ultrasonics (AU), a guided plate-wave inspection modality that has attracted strong interest due mainly to its capacity to furnish wide-area diagnostic coverage with a relatively low sensor density. This article provides a detailed description of the development, testing and demonstration of a new AU interrogation system called the Acousto Ultrasonic Structural health monitoring Array Module⁺ (AUSAM⁺). This system provides independent actuation and sensing on four Piezoelectric Wafer Active Sensor (PWAS) elements with further sensing on four Positive Intrinsic Negative (PIN) photodiodes for intensity-based interrogation of Fiber Bragg Gratings (FBG). The paper details the development of a novel piezoelectric excitation amplifier, which, in conjunction with flexible acquisition-system architecture, seamlessly provides electromechanical impedance spectroscopy for PWAS diagnostics over the full instrument bandwidth of 50 KHz-5 MHz. The AUSAM⁺ functionality is accessed via a simple hardware object providing a myriad of custom software interfaces that can be adapted to suit the specific requirements of each individual application.
Smithard, Joel; Rajic, Nik; Norman, Patrick; Rosalie, Cedric; Galea, Steve; Mei, Hanfei; Lin, Bin; Giurgiutiu, Victor
2017-01-01
A key longstanding objective of the Structural Health Monitoring (SHM) research community is to enable the embedment of SHM systems in high value assets like aircraft to provide on-demand damage detection and evaluation. As against traditional non-destructive inspection hardware, embedded SHM systems must be compact, lightweight, low-power and sufficiently robust to survive exposure to severe in-flight operating conditions. Typical Commercial-Off-The-Shelf (COTS) systems can be bulky, costly and are often inflexible in their configuration and/or scalability, which militates against in-service deployment. Advances in electronics have resulted in ever smaller, cheaper and more reliable components that facilitate the development of compact and robust embedded SHM systems, including for Acousto-Ultrasonics (AU), a guided plate-wave inspection modality that has attracted strong interest due mainly to its capacity to furnish wide-area diagnostic coverage with a relatively low sensor density. This article provides a detailed description of the development, testing and demonstration of a new AU interrogation system called the Acousto Ultrasonic Structural health monitoring Array Module+ (AUSAM+). This system provides independent actuation and sensing on four Piezoelectric Wafer Active Sensor (PWAS) elements with further sensing on four Positive Intrinsic Negative (PIN) photodiodes for intensity-based interrogation of Fiber Bragg Gratings (FBG). The paper details the development of a novel piezoelectric excitation amplifier, which, in conjunction with flexible acquisition-system architecture, seamlessly provides electromechanical impedance spectroscopy for PWAS diagnostics over the full instrument bandwidth of 50 KHz–5 MHz. The AUSAM+ functionality is accessed via a simple hardware object providing a myriad of custom software interfaces that can be adapted to suit the specific requirements of each individual application. PMID:28773193
Fast Interrogation of Fiber Bragg Gratings with Electro-Optical Dual Optical Frequency Combs
Posada-Roman, Julio E.; Garcia-Souto, Jose A.; Poiana, Dragos A.; Acedo, Pablo
2016-01-01
Optical frequency combs (OFC) generated by electro-optic modulation of continuous-wave lasers provide broadband coherent sources with high power per line and independent control of line spacing and the number of lines. In addition to their application in spectroscopy, they offer flexible and optimized sources for the interrogation of other sensors based on wavelength change or wavelength filtering, such as fiber Bragg grating (FBG) sensors. In this paper, a dual-OFC FBG interrogation system based on a single laser and two optical-phase modulators is presented. This architecture allows for the configuration of multimode optical source parameters such as the number of modes and their position within the reflected spectrum of the FBG. A direct read-out is obtained by mapping the optical spectrum onto the radio-frequency spectrum output of the dual-comb. This interrogation scheme is proposed for measuring fast phenomena such as vibrations and ultrasounds. Results are presented for dual-comb operation under optimized control. The optical modes are mapped onto detectable tones that are multiples of 0.5 MHz around a center radiofrequency tone (40 MHz). Measurements of ultrasounds (40 kHz and 120 kHz) are demonstrated with this sensing system. Ultrasounds induce dynamic strain onto the fiber, which generates changes in the reflected Bragg wavelength and, hence, modulates the amplitude of the OFC modes within the reflected spectrum. The amplitude modulation of two counterphase tones is detected to obtain a differential measurement proportional to the ultrasound signal. PMID:27898043
Fast Interrogation of Fiber Bragg Gratings with Electro-Optical Dual Optical Frequency Combs.
Posada-Roman, Julio E; Garcia-Souto, Jose A; Poiana, Dragos A; Acedo, Pablo
2016-11-26
Optical frequency combs (OFC) generated by electro-optic modulation of continuous-wave lasers provide broadband coherent sources with high power per line and independent control of line spacing and the number of lines. In addition to their application in spectroscopy, they offer flexible and optimized sources for the interrogation of other sensors based on wavelength change or wavelength filtering, such as fiber Bragg grating (FBG) sensors. In this paper, a dual-OFC FBG interrogation system based on a single laser and two optical-phase modulators is presented. This architecture allows for the configuration of multimode optical source parameters such as the number of modes and their position within the reflected spectrum of the FBG. A direct read-out is obtained by mapping the optical spectrum onto the radio-frequency spectrum output of the dual-comb. This interrogation scheme is proposed for measuring fast phenomena such as vibrations and ultrasounds. Results are presented for dual-comb operation under optimized control. The optical modes are mapped onto detectable tones that are multiples of 0.5 MHz around a center radiofrequency tone (40 MHz). Measurements of ultrasounds (40 kHz and 120 kHz) are demonstrated with this sensing system. Ultrasounds induce dynamic strain onto the fiber, which generates changes in the reflected Bragg wavelength and, hence, modulates the amplitude of the OFC modes within the reflected spectrum. The amplitude modulation of two counterphase tones is detected to obtain a differential measurement proportional to the ultrasound signal.
[A metapsychological reading of questioning by police and during criminal investigations].
Sztulman, H; Rousseaux, N
1990-01-01
The pursuit and reception of a confession during police interrogation and cross examination lead to a dynamic interaction between interrogator and interrogated which can be examined under the light of psychoanalytical concepts. This reference framework enables a reading of the different positions occupied by the interrogator with regard to the interrogated, and allows to understand certain mechanisms in the arrival of a confession as well as some of its effects.
Archival Information Management System.
1995-02-01
management system named Archival Information Management System (AIMS), designed to meet the audit trail requirement for studies completed under the...are to be archived to the extent that future reproducibility and interrogation of results will exist. This report presents a prototype information
Distributed gas detection system and method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Challener, William Albert; Palit, Sabarni; Karp, Jason Harris
A distributed gas detection system includes one or more hollow core fibers disposed in different locations, one or more solid core fibers optically coupled with the one or more hollow core fibers and configured to receive light of one or more wavelengths from a light source, and an interrogator device configured to receive at least some of the light propagating through the one or more solid core fibers and the one or more hollow core fibers. The interrogator device is configured to identify a location of a presence of a gas-of-interest by examining absorption of at least one of themore » wavelengths of the light at least one of the hollow core fibers.« less
32 CFR 637.21 - Recording interviews and interrogations.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 32 National Defense 4 2011-07-01 2011-07-01 false Recording interviews and interrogations. 637.21 Section 637.21 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) LAW... interviews and interrogations. The recording of interviews and interrogations by military police personnel is...
32 CFR 637.21 - Recording interviews and interrogations.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 32 National Defense 4 2012-07-01 2011-07-01 true Recording interviews and interrogations. 637.21 Section 637.21 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) LAW... interviews and interrogations. The recording of interviews and interrogations by military police personnel is...
32 CFR 637.21 - Recording interviews and interrogations.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 32 National Defense 4 2013-07-01 2013-07-01 false Recording interviews and interrogations. 637.21 Section 637.21 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) LAW... interviews and interrogations. The recording of interviews and interrogations by military police personnel is...
32 CFR 637.21 - Recording interviews and interrogations.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 32 National Defense 4 2014-07-01 2013-07-01 true Recording interviews and interrogations. 637.21 Section 637.21 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) LAW... interviews and interrogations. The recording of interviews and interrogations by military police personnel is...
32 CFR 637.21 - Recording interviews and interrogations.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 32 National Defense 4 2010-07-01 2010-07-01 true Recording interviews and interrogations. 637.21 Section 637.21 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) LAW... interviews and interrogations. The recording of interviews and interrogations by military police personnel is...
Synthesis of mimics of pramanicin from pyroglutamic acid and their antibacterial activity.
Tan, Song Wei Benjamin; Chai, Christina L L; Moloney, Mark G; Thompson, Amber L
2015-03-06
Epoxypyrrolidinones are available by epoxidation of carboxamide-activated bicyclic lactam substrates derived from pyroglutamate using aqueous hydrogen peroxide and tertiary amine catalysis. In the case of an activating Weinreb carboxamide, further chemoselective elaboration leads to the efficient formation of libraries of epoxyketones. Deprotection may be achieved under acidic conditions to give epoxypyroglutaminols, although the ease of this process can be ameliorated by the presence of internal hydrogen bonding. Bioassay against S. aureus and E. coli indicated that some compounds exhibit antibacterial activity. These libraries may be considered to be structural mimics of the natural products pramanicin and epolactaene. More generally, this outcome suggests that interrogation of bioactive natural products is likely to permit the identification of "privileged" structural scaffolds, providing frameworks suitable for optimization in a short series of chemical steps that may accelerate the discovery of new antibiotic chemotypes. Further optimization of such systems may permit the rapid identification of novel systems suitable for antibacterial drug development.
Pang, Cheng; Bae, Hyungdae; Gupta, Ashwani; Bryden, Kenneth; Yu, Miao
2013-09-23
We present a micro-electro-mechanical systems (MEMS) based Fabry-Perot (FP) sensor along with an optical system-on-a-chip (SOC) interrogator for simultaneous pressure and temperature sensing. The sensor employs a simple structure with an air-backed silicon membrane cross-axially bonded to a 45° polished optical fiber. This structure renders two cascaded FP cavities, enabling simultaneous pressure and temperature sensing in close proximity along the optical axis. The optical SOC consists of a broadband source, a MEMS FP tunable filter, a photodetector, and the supporting circuitry, serving as a miniature spectrometer for retrieving the two FP cavity lengths. Within the measured pressure and temperature ranges, experimental results demonstrate that the sensor exhibits a good linear response to external pressure and temperature changes.
29 CFR 18.611 - Mode and order of interrogation and presentation.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 29 Labor 1 2010-07-01 2010-07-01 true Mode and order of interrogation and presentation. 18.611... of interrogation and presentation. (a) Control by judge. The judge shall exercise reasonable control... interrogation and presentation effective for the ascertainment of the truth, (2) Avoid needless consumption of...
48 CFR 252.237-7010 - Prohibition on interrogation of detainees by contractor personnel.
Code of Federal Regulations, 2014 CFR
2014-10-01
... interrogation of detainees by contractor personnel. 252.237-7010 Section 252.237-7010 Federal Acquisition... interrogation of detainees by contractor personnel. As prescribed in 237.173-5, use the following clause: Prohibition on Interrogation of Detainees by Contractor Personnel ((JUN 2013)) (a) Definitions. As used in...
ERIC Educational Resources Information Center
Ozgungor, Sevgi; Guthrie, John T.
2004-01-01
The authors examined the impact of elaborative interrogation on knowledge construction during expository text reading, specifically, the interactions among elaborative interrogation, knowledge, and interest. Three measures of learning were taken: recall, inference, and coherence. Elaborative interrogation affected all aspects of learning measured,…
29 CFR 18.611 - Mode and order of interrogation and presentation.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 29 Labor 1 2011-07-01 2011-07-01 false Mode and order of interrogation and presentation. 18.611... of interrogation and presentation. (a) Control by judge. The judge shall exercise reasonable control... interrogation and presentation effective for the ascertainment of the truth, (2) Avoid needless consumption of...
29 CFR 18.611 - Mode and order of interrogation and presentation.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 29 Labor 1 2012-07-01 2012-07-01 false Mode and order of interrogation and presentation. 18.611... of interrogation and presentation. (a) Control by judge. The judge shall exercise reasonable control... interrogation and presentation effective for the ascertainment of the truth, (2) Avoid needless consumption of...
48 CFR 252.237-7010 - Prohibition on interrogation of detainees by contractor personnel.
Code of Federal Regulations, 2013 CFR
2013-10-01
... interrogation of detainees by contractor personnel. 252.237-7010 Section 252.237-7010 Federal Acquisition... interrogation of detainees by contractor personnel. As prescribed in 237.173-5, use the following clause: Prohibition on Interrogation of Detainees by Contractor Personnel ((JUN 2013)) (a) Definitions. As used in...
25 CFR 11.303 - Notification of rights prior to custodial interrogation.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 25 Indians 1 2013-04-01 2013-04-01 false Notification of rights prior to custodial interrogation. 11.303 Section 11.303 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER... to custodial interrogation. Prior to custodial interrogation, the suspect shall be advised of the...
25 CFR 11.303 - Notification of rights prior to custodial interrogation.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 25 Indians 1 2011-04-01 2011-04-01 false Notification of rights prior to custodial interrogation. 11.303 Section 11.303 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER... to custodial interrogation. Prior to custodial interrogation, the suspect shall be advised of the...
29 CFR 18.611 - Mode and order of interrogation and presentation.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 29 Labor 1 2013-07-01 2013-07-01 false Mode and order of interrogation and presentation. 18.611... of interrogation and presentation. (a) Control by judge. The judge shall exercise reasonable control... interrogation and presentation effective for the ascertainment of the truth, (2) Avoid needless consumption of...
25 CFR 11.303 - Notification of rights prior to custodial interrogation.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 1 2010-04-01 2010-04-01 false Notification of rights prior to custodial interrogation. 11.303 Section 11.303 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER... to custodial interrogation. Prior to custodial interrogation, the suspect shall be advised of the...
29 CFR 18.611 - Mode and order of interrogation and presentation.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 29 Labor 1 2014-07-01 2013-07-01 true Mode and order of interrogation and presentation. 18.611... of interrogation and presentation. (a) Control by judge. The judge shall exercise reasonable control... interrogation and presentation effective for the ascertainment of the truth, (2) Avoid needless consumption of...
25 CFR 11.303 - Notification of rights prior to custodial interrogation.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 25 Indians 1 2014-04-01 2014-04-01 false Notification of rights prior to custodial interrogation. 11.303 Section 11.303 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER... to custodial interrogation. Prior to custodial interrogation, the suspect shall be advised of the...
25 CFR 11.303 - Notification of rights prior to custodial interrogation.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 25 Indians 1 2012-04-01 2011-04-01 true Notification of rights prior to custodial interrogation. 11.303 Section 11.303 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER... to custodial interrogation. Prior to custodial interrogation, the suspect shall be advised of the...
ERIC Educational Resources Information Center
Scruggs, Thomas E.; And Others
1993-01-01
Fifty-three adolescents with learning disabilities or mild mental retardation were taught reasons for dinosaur extinction. Those taught in a mnemonic elaborative interrogation condition recalled more reasons than did students who received direct teaching. Students in elaborative interrogation and mnemonic elaborative interrogation groups recalled…
Model validation of untethered, ultrasonic neural dust motes for cortical recording.
Seo, Dongjin; Carmena, Jose M; Rabaey, Jan M; Maharbiz, Michel M; Alon, Elad
2015-04-15
A major hurdle in brain-machine interfaces (BMI) is the lack of an implantable neural interface system that remains viable for a substantial fraction of the user's lifetime. Recently, sub-mm implantable, wireless electromagnetic (EM) neural interfaces have been demonstrated in an effort to extend system longevity. However, EM systems do not scale down in size well due to the severe inefficiency of coupling radio-waves at those scales within tissue. This paper explores fundamental system design trade-offs as well as size, power, and bandwidth scaling limits of neural recording systems built from low-power electronics coupled with ultrasonic power delivery and backscatter communication. Such systems will require two fundamental technology innovations: (1) 10-100 μm scale, free-floating, independent sensor nodes, or neural dust, that detect and report local extracellular electrophysiological data via ultrasonic backscattering and (2) a sub-cranial ultrasonic interrogator that establishes power and communication links with the neural dust. We provide experimental verification that the predicted scaling effects follow theory; (127 μm)(3) neural dust motes immersed in water 3 cm from the interrogator couple with 0.002064% power transfer efficiency and 0.04246 ppm backscatter, resulting in a maximum received power of ∼0.5 μW with ∼1 nW of change in backscatter power with neural activity. The high efficiency of ultrasonic transmission can enable the scaling of the sensing nodes down to 10s of micrometer. We conclude with a brief discussion of the application of neural dust for both central and peripheral nervous system recordings, and perspectives on future research directions. Copyright © 2014 Elsevier B.V. All rights reserved.
Duplex Interrogation by a Direct DNA Repair Protein in Search of Base Damage
Yi, Chengqi; Chen, Baoen; Qi, Bo; Zhang, Wen; Jia, Guifang; Zhang, Liang; Li, Charles J.; Dinner, Aaron R.; Yang, Cai-Guang; He, Chuan
2012-01-01
ALKBH2 is a direct DNA repair dioxygenase guarding mammalian genome against N1-methyladenine, N3-methylcytosine, and 1,N6-ethenoadenine damage. A prerequisite for repair is to identify these lesions in the genome. Here we present crystal structures of ALKBH2 bound to different duplex DNAs. Together with computational and biochemical analyses, our results suggest that DNA interrogation by ALKBH2 displays two novel features: i) ALKBH2 probes base-pair stability and detects base pairs with reduced stability; ii) ALKBH2 does not have nor need a “damage-checking site”, which is critical for preventing spurious base-cleavage for several glycosylases. The demethylation mechanism of ALKBH2 insures that only cognate lesions are oxidized and reversed to normal bases, and that a flipped, non-substrate base remains intact in the active site. Overall, the combination of duplex interrogation and oxidation chemistry allows ALKBH2 to detect and process diverse lesions efficiently and correctly. PMID:22659876
Laser interrogation techniques for high-sensitivity strain sensing by fiber-Bragg-grating structures
NASA Astrophysics Data System (ADS)
Gagliardi, G.; Salza, M.; Ferraro, P.; De Natale, P.
2017-11-01
Novel interrogation methods for static and dynamic measurements of mechanical deformations by fiber Bragg-gratings (FBGs) structures are presented. The sensor-reflected radiation gives information on suffered strain, with a sensitivity dependent on the interrogation setup. Different approaches have been carried out, based on laser-frequency modulation techniques and near-IR lasers, to measure strain in single-FBG and in resonant high-reflectivity FBG arrays. In particular, for the fiber resonator, the laser frequency is actively locked to the cavity resonances by the Pound-Drever-Hall technique, thus tracking any frequency change due to deformations. The loop error and correction signals fed back to the laser are used as strain monitor. Sensitivity limits vary between 200 nɛ/√Hz in the quasi-static domain (0.5÷2 Hz), and between 1 and 4 nɛ/√Hz in the 0.4-1 kHz range for the single-FBG scheme, while strain down to 50 pɛ can be detected by using the laser-cavity-locked method.
48 CFR 252.237-7010 - Prohibition on interrogation of detainees by contractor personnel.
Code of Federal Regulations, 2012 CFR
2012-10-01
... interrogation of detainees by contractor personnel. 252.237-7010 Section 252.237-7010 Federal Acquisition... interrogation of detainees by contractor personnel. As prescribed in 237.173-5, use the following clause: Prohibition on Interrogation of Detainees by Contractor Personnel (NOV 2010) (a) Definitions. As used in this...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Interrogation. 343b.3 Section 343b.3 Aliens... NATURALIZATION FOR RECOGNITION BY A FOREIGN STATE § 343b.3 Interrogation. When Form N-565 presents a prima facie... issuance of the certificate. Interrogation of the applicant shall be conducted before the application is...
14 CFR 91.215 - ATC transponder and altitude reporting equipment and use.
Code of Federal Regulations, 2013 CFR
2013-01-01
... interrogations with the code specified by ATC, or a Mode S capability, replying to Mode 3/A interrogations with the code specified by ATC and intermode and Mode S interrogations in accordance with the applicable... equipment having a Mode C capability that automatically replies to Mode C interrogations by transmitting...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Interrogation. 343b.3 Section 343b.3 Aliens... NATURALIZATION FOR RECOGNITION BY A FOREIGN STATE § 343b.3 Interrogation. When Form N-565 presents a prima facie... issuance of the certificate. Interrogation of the applicant shall be conducted before the application is...
14 CFR 91.215 - ATC transponder and altitude reporting equipment and use.
Code of Federal Regulations, 2010 CFR
2010-01-01
... interrogations with the code specified by ATC, or a Mode S capability, replying to Mode 3/A interrogations with the code specified by ATC and intermode and Mode S interrogations in accordance with the applicable... equipment having a Mode C capability that automatically replies to Mode C interrogations by transmitting...
14 CFR 91.215 - ATC transponder and altitude reporting equipment and use.
Code of Federal Regulations, 2011 CFR
2011-01-01
... interrogations with the code specified by ATC, or a Mode S capability, replying to Mode 3/A interrogations with the code specified by ATC and intermode and Mode S interrogations in accordance with the applicable... equipment having a Mode C capability that automatically replies to Mode C interrogations by transmitting...
14 CFR 91.215 - ATC transponder and altitude reporting equipment and use.
Code of Federal Regulations, 2012 CFR
2012-01-01
... interrogations with the code specified by ATC, or a Mode S capability, replying to Mode 3/A interrogations with the code specified by ATC and intermode and Mode S interrogations in accordance with the applicable... equipment having a Mode C capability that automatically replies to Mode C interrogations by transmitting...
14 CFR 91.215 - ATC transponder and altitude reporting equipment and use.
Code of Federal Regulations, 2014 CFR
2014-01-01
... interrogations with the code specified by ATC, or a Mode S capability, replying to Mode 3/A interrogations with the code specified by ATC and intermode and Mode S interrogations in accordance with the applicable... equipment having a Mode C capability that automatically replies to Mode C interrogations by transmitting...
48 CFR 252.237-7010 - Prohibition on interrogation of detainees by contractor personnel.
Code of Federal Regulations, 2011 CFR
2011-10-01
... interrogation of detainees by contractor personnel. 252.237-7010 Section 252.237-7010 Federal Acquisition... interrogation of detainees by contractor personnel. As prescribed in 237.173-5, use the following clause: PROHIBITION ON INTERROGATION OF DETAINEES BY CONTRACTOR PERSONNEL (NOV 2010) (a) Definitions. As used in this...
What do potential jurors know about police interrogation techniques and false confessions?
Leo, Richard A; Liu, Brittany
2009-01-01
Psychological police interrogation methods in America inevitably involve some level of pressure and persuasion to achieve their goal of eliciting confessions of guilt from custodial suspects. In this article, we surveyed potential jurors about their perceptions of a range of psychological interrogation techniques, the likelihood that such techniques would elicit a true confession from guilty suspects, and the likelihood that such techniques could elicit a false confession from innocent suspects. Participants recognized that these interrogation techniques may be psychologically coercive and may elicit true confessions, but believed that psychologically coercive interrogation techniques are not likely to elicit false confessions. The findings from this survey study indicate that potential jurors believe that false confessions are both counter- intuitive and unlikely, even in response to psychologically coercive interrogation techniques that have been shown to lead to false confessions from the innocent. This study provides empirical support for the idea that expert witnesses may helpfully inform jurors about the social science research on psychologically coercive interrogation methods and how and why such interrogation techniques can lead to false confessions. (c) 2009 John Wiley & Sons, Ltd.
Cleary, Hayley M D; Warner, Todd C
2016-06-01
Despite empirical progress in documenting and classifying various interrogation techniques, very little is known about how police are trained in interrogation methods, how frequently they use various techniques, and whether they employ techniques differentially with adult versus juvenile suspects. This study reports the nature and extent of formal (e.g., Reid Technique, PEACE, HUMINT) and informal interrogation training as well as self-reported technique usage in a diverse national sample (N = 340) of experienced American police officers. Officers were trained in a variety of different techniques ranging from comparatively benign pre-interrogation strategies (e.g., building rapport, observing body language or speech patterns) to more psychologically coercive techniques (e.g., blaming the victim, discouraging denials). Over half the sample reported being trained to use psychologically coercive techniques with both adults and juveniles. The majority (91%) receive informal, "on the job" interrogation training. Technique usage patterns indicate a spectrum of psychological intensity where information-gathering approaches were used most frequently and high-pressure tactics less frequently. Reid-trained officers (56%) were significantly more likely than officers without Reid training to use pre-interrogation and manipulation techniques. Across all analyses and techniques, usage patterns were identical for adult and juvenile suspects, suggesting that police interrogate youth in the same manner as adults. Overall, results suggest that training in specific interrogation methods is strongly associated with usage. Findings underscore the need for more law enforcement interrogation training in general, especially with juvenile suspects, and highlight the value of training as an avenue for reducing interrogation-induced miscarriages of justice. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
NASA Technical Reports Server (NTRS)
Glover, R. D.
1983-01-01
The NASA Dryden Flight Research Facility has developed a microprocessor-based, user-programmable, general-purpose aircraft interrogation and display system (AIDS). The hardware and software of this ground-support equipment have been designed to permit diverse applications in support of aircraft digital flight-control systems and simulation facilities. AIDS is often employed to provide engineering-units display of internal digital system parameters during development and qualification testing. Such visibility into the system under test has proved to be a key element in the final qualification testing of aircraft digital flight-control systems. Three first-generation 8-bit units are now in service in support of several research aircraft projects, and user acceptance has been high. A second-generation design, extended AIDS (XAIDS), incorporating multiple 16-bit processors, is now being developed to support the forward swept wing aircraft project (X-29A). This paper outlines the AIDS concept, summarizes AIDS operational experience, and describes the planned XAIDS design and mechanization.
Towards isozyme-selective HDAC inhibitors for interrogating disease.
Gupta, Praveer; Reid, Robert C; Iyer, Abishek; Sweet, Matthew J; Fairlie, David P
2012-01-01
Histone deacetylase (HDAC) enzymes have emerged as promising targets for the treatment of a wide range of human diseases, including cancers, inflammatory and metabolic disorders, immunological, cardiovascular, and infectious diseases. At present, such applications are limited by the lack of selective inhibitors available for each of the eighteen HDAC enzymes, with most currently available HDAC inhibitors having broad-spectrum activity against multiple HDAC enzymes. Such broad-spectrum activity maybe useful in treating some diseases like cancers, but can be detrimental due to cytotoxic side effects that accompany prolonged treatment of chronic diseased states. Here we summarize progress towards the design and discovery of HDAC inhibitors that are selective for some of the eleven zinc-containing classical HDAC enzymes, and identify opportunities to use such isozyme-selective inhibitors as chemical probes for interrogating the biological roles of individual HDAC enzymes in diseases.
Janofsky, Jeffrey S
2006-01-01
Police interrogators routinely use deceptive techniques to obtain confessions from criminal suspects. The United States Executive Branch has attempted to justify coercive interrogation techniques in which physical or mental pain and suffering may be used during intelligence interrogations of persons labeled unlawful combatants. It may be appropriate for law enforcement, military, or intelligence personnel who are not physicians to use such techniques. However, forensic psychiatry ethical practice requires honesty, striving for objectivity, and respect for persons. Deceptive and coercive interrogation techniques violate these moral values. When a psychiatrist directly uses, works with others who use, or trains others to use deceptive or coercive techniques to obtain information in police, military, or intelligence interrogations, the psychiatrist breaches basic principles of ethics.
Non-Gaussian precision metrology via driving through quantum phase transitions
NASA Astrophysics Data System (ADS)
Huang, Jiahao; Zhuang, Min; Lee, Chaohong
2018-03-01
We propose a scheme to realize high-precision quantum interferometry with entangled non-Gaussian states by driving the system through quantum phase transitions. The beam splitting, in which an initial nondegenerate ground state evolves into a highly entangled state, is achieved by adiabatically driving the system from a nondegenerate regime to a degenerate one. Inversely, the beam recombination, in which the output state after interrogation becomes gradually disentangled, is accomplished by adiabatically driving the system from the degenerate regime to the nondegenerate one. The phase shift, which is accumulated in the interrogation process, can then be easily inferred via population measurement. We apply our scheme to Bose condensed atoms and trapped ions and find that Heisenberg-limited precision scalings can be approached. Our proposed scheme does not require single-particle resolved detection and is within the reach of current experiment techniques.
DOT National Transportation Integrated Search
1975-04-01
The report describes a computer simulation of the Air Traffic Control Radar Beacon System (ATCRBS). Operating on real air traffic data and actual characteristics of the relevant ground interrogators, the FORTRAN program re-enacts system operation in ...
DOT National Transportation Integrated Search
1975-04-01
The report describes a computer simulation of the Air Traffic Control Radar Beacon System (ATCRBS). Operating on real air traffic data and actual characteristics of the relevant ground interrogators, the FORTRAN program re-enacts system operation in ...
Safety and efficiency of emergency department interrogation of cardiac devices
Neuenschwander, James F.; Peacock, W. Frank; Migeed, Madgy; Hunter, Sara A.; Daughtery, John C.; McCleese, Ian C.; Hiestand, Brian C.
2016-01-01
Objective Patients with implanted cardiac devices may wait extended periods for interrogation in emergency departments (EDs). Our purpose was to determine if device interrogation could be done safely and faster by ED staff. Methods Prospective randomized, standard therapy controlled, trial of ED staff device interrogation vs. standard process (SP), with 30-day follow-up. Eligibility criteria: ED presentation with a self-report of a potential device related complaint, with signed informed consent. SP interrogation was by company representative or hospital employee. Results Of 60 patients, 42 (70%) were male, all were white, with a median (interquartile range) age of 71 (64 to 82) years. No patient was lost to follow up. Of all patients, 32 (53%) were enrolled during business hours. The overall median (interquartile range) ED vs. SP time to interrogation was 98.5 (40 to 260) vs. 166.5 (64 to 412) minutes (P=0.013). While ED and SP interrogation times were similar during business hours, 102 (59 to 138) vs. 105 (64 to 172) minutes (P=0.62), ED interrogation times were shorter vs. SP during non-business hours; 97 (60 to 126) vs. 225 (144 to 412) minutes, P=0.002, respectively. There was no difference in ED length of stay between the ED and SP interrogation, 249 (153 to 390) vs. 246 (143 to 333) minutes (P=0.71), regardless of time of presentation. No patient in any cohort suffered an unplanned medical contact or post-discharge adverse device related event. Conclusion ED staff cardiac device interrogations are faster, and with similar 30-day outcomes, as compared to SP. PMID:28168230
Safety and efficiency of emergency department interrogation of cardiac devices.
Neuenschwander, James F; Peacock, W Frank; Migeed, Madgy; Hunter, Sara A; Daughtery, John C; McCleese, Ian C; Hiestand, Brian C
2016-12-01
Patients with implanted cardiac devices may wait extended periods for interrogation in emergency departments (EDs). Our purpose was to determine if device interrogation could be done safely and faster by ED staff. Prospective randomized, standard therapy controlled, trial of ED staff device interrogation vs. standard process (SP), with 30-day follow-up. Eligibility criteria: ED presentation with a self-report of a potential device related complaint, with signed informed consent. SP interrogation was by company representative or hospital employee. Of 60 patients, 42 (70%) were male, all were white, with a median (interquartile range) age of 71 (64 to 82) years. No patient was lost to follow up. Of all patients, 32 (53%) were enrolled during business hours. The overall median (interquartile range) ED vs. SP time to interrogation was 98.5 (40 to 260) vs. 166.5 (64 to 412) minutes (P=0.013). While ED and SP interrogation times were similar during business hours, 102 (59 to 138) vs. 105 (64 to 172) minutes (P=0.62), ED interrogation times were shorter vs. SP during non-business hours; 97 (60 to 126) vs. 225 (144 to 412) minutes, P=0.002, respectively. There was no difference in ED length of stay between the ED and SP interrogation, 249 (153 to 390) vs. 246 (143 to 333) minutes (P=0.71), regardless of time of presentation. No patient in any cohort suffered an unplanned medical contact or post-discharge adverse device related event. ED staff cardiac device interrogations are faster, and with similar 30-day outcomes, as compared to SP.
Portable fluorescence lifetime spectroscopy system for in-situ interrogation of biological tissues
NASA Astrophysics Data System (ADS)
Saito Nogueira, Marcelo; Cosci, Alessandro; Teixeira Rosa, Ramon Gabriel; Salvio, Ana Gabriela; Pratavieira, Sebastião; Kurachi, Cristina
2017-12-01
Fluorescence spectroscopy and lifetime techniques are potential methods for optical diagnosis and characterization of biological tissues with an in-situ, fast, and noninvasive interrogation. Several diseases may be diagnosed due to differences in the fluorescence spectra of targeted fluorophores, when, these spectra are similar, considering steady-state fluorescence, others may be detected by monitoring their fluorescence lifetime. Despite this complementarity, most of the current fluorescence lifetime systems are not robust and portable, and not being feasible for clinical applications. We describe the assembly of a fluorescence lifetime spectroscopy system in a suitcase, its characterization, and validation with clinical measurements of skin lesions. The assembled system is all encased and robust, maintaining its mechanical, electrical, and optical stability during transportation, and is feasible for clinical measurements. The instrument response function measured was about 300 ps, and the system is properly calibrated. At the clinical study, the system showed to be reliable, and the achieved spectroscopy results support its potential use as an auxiliary tool for skin diagnostics.
Detection of fissionable materials in cargoes using monochromatic photon radiography
NASA Astrophysics Data System (ADS)
Danagoulian, Areg; Lanza, Richard; O'Day, Buckley; LNSP Team
2015-04-01
The detection of Special Nuclear Materials (e.g. Pu and U) and nuclear devices in the commercial cargo traffic is one of the challenges posed by the threat of nuclear terrorism. Radiography and active interrogation of heavily loaded cargoes require ~ 1 - 10MeV photons for penetration. In a proof-of-concept system under development at MIT, the interrogating monochromatic photon beam is produced via a 11B(d , nγ) 12C reaction. To achieve this, a boron target is used along with the 3 MeV d+ RFQ accelerator at MIT-Bates. The reactions results in the emission of very narrow 4.4 MeV and 15.1 MeV gammas lines. The photons, after traversing the cargo, are detected by an array of NaI(Tl) detectors. A spectral analysis of the transmitted gammas allows to independently determine the areal density and the atomic number (Z) of the cargo. The proposed approach could revolutionize cargo inspection, which, in its current fielded form has to rely on simple but high dose bremsstrahlung sources. Use of monochromatic sources would significantly reduce the necessary dose and allow for better determination of the cargo's atomic number. The general methodology will be described and the preliminary results from the proof-of-concept system will be presented and discussed. Supported by NSF/DNDO Collaborative Research ARI-LA Award ECCS-1348328.
Time to "go large" on biofilm research: advantages of an omics approach.
Azevedo, Nuno F; Lopes, Susana P; Keevil, Charles W; Pereira, Maria O; Vieira, Maria J
2009-04-01
In nature, the biofilm mode of life is of great importance in the cell cycle for many microorganisms. Perhaps because of biofilm complexity and variability, the characterization of a given microbial system, in terms of biofilm formation potential, structure and associated physiological activity, in a large-scale, standardized and systematic manner has been hindered by the absence of high-throughput methods. This outlook is now starting to change as new methods involving the utilization of microtiter-plates and automated spectrophotometry and microscopy systems are being developed to perform large-scale testing of microbial biofilms. Here, we evaluate if the time is ripe to start an integrated omics approach, i.e., the generation and interrogation of large datasets, to biofilms--"biofomics". This omics approach would bring much needed insight into how biofilm formation ability is affected by a number of environmental, physiological and mutational factors and how these factors interplay between themselves in a standardized manner. This could then lead to the creation of a database where biofilm signatures are identified and interrogated. Nevertheless, and before embarking on such an enterprise, the selection of a versatile, robust, high-throughput biofilm growing device and of appropriate methods for biofilm analysis will have to be performed. Whether such device and analytical methods are already available, particularly for complex heterotrophic biofilms is, however, very debatable.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tweardy, Matthew C.; McConchie, Seth; Hayward, Jason P.
An extension of the point kinetics model is developed in this paper to describe the neutron multiplicity response of a bare uranium object under interrogation by an associated particle imaging deuterium-tritium (D-T) measurement system. This extended model is used to estimate the total neutron multiplication of the uranium. Both MCNPX-PoliMi simulations and data from active interrogation measurements of highly enriched and depleted uranium geometries are used to evaluate the potential of this method and to identify the sources of systematic error. The detection efficiency correction for measured coincidence response is identified as a large source of systematic error. If themore » detection process is not considered, results suggest that the method can estimate total multiplication to within 13% of the simulated value. Values for multiplicity constants in the point kinetics equations are sensitive to enrichment due to (n, xn) interactions by D-T neutrons and can introduce another significant source of systematic bias. This can theoretically be corrected if isotopic composition is known a priori. Finally, the spatial dependence of multiplication is also suspected of introducing further systematic bias for high multiplication uranium objects.« less
Tweardy, Matthew C.; McConchie, Seth; Hayward, Jason P.
2017-06-13
An extension of the point kinetics model is developed in this paper to describe the neutron multiplicity response of a bare uranium object under interrogation by an associated particle imaging deuterium-tritium (D-T) measurement system. This extended model is used to estimate the total neutron multiplication of the uranium. Both MCNPX-PoliMi simulations and data from active interrogation measurements of highly enriched and depleted uranium geometries are used to evaluate the potential of this method and to identify the sources of systematic error. The detection efficiency correction for measured coincidence response is identified as a large source of systematic error. If themore » detection process is not considered, results suggest that the method can estimate total multiplication to within 13% of the simulated value. Values for multiplicity constants in the point kinetics equations are sensitive to enrichment due to (n, xn) interactions by D-T neutrons and can introduce another significant source of systematic bias. This can theoretically be corrected if isotopic composition is known a priori. Finally, the spatial dependence of multiplication is also suspected of introducing further systematic bias for high multiplication uranium objects.« less
An overview of wireless structural health monitoring for civil structures.
Lynch, Jerome Peter
2007-02-15
Wireless monitoring has emerged in recent years as a promising technology that could greatly impact the field of structural monitoring and infrastructure asset management. This paper is a summary of research efforts that have resulted in the design of numerous wireless sensing unit prototypes explicitly intended for implementation in civil structures. Wireless sensing units integrate wireless communications and mobile computing with sensors to deliver a relatively inexpensive sensor platform. A key design feature of wireless sensing units is the collocation of computational power and sensors; the tight integration of computing with a wireless sensing unit provides sensors with the opportunity to self-interrogate measurement data. In particular, there is strong interest in using wireless sensing units to build structural health monitoring systems that interrogate structural data for signs of damage. After the hardware and the software designs of wireless sensing units are completed, the Alamosa Canyon Bridge in New Mexico is utilized to validate their accuracy and reliability. To improve the ability of low-cost wireless sensing units to detect the onset of structural damage, the wireless sensing unit paradigm is extended to include the capability to command actuators and active sensors.
Detecting fission from special nuclear material sources
Rowland, Mark S [Alamo, CA; Snyderman, Neal J [Berkeley, CA
2012-06-05
A neutron detector system for discriminating fissile material from non-fissile material wherein a digital data acquisition unit collects data at high rate, and in real-time processes large volumes of data directly into information that a first responder can use to discriminate materials. The system comprises counting neutrons from the unknown source and detecting excess grouped neutrons to identify fission in the unknown source. The system includes a graphing component that displays the plot of the neutron distribution from the unknown source over a Poisson distribution and a plot of neutrons due to background or environmental sources. The system further includes a known neutron source placed in proximity to the unknown source to actively interrogate the unknown source in order to accentuate differences in neutron emission from the unknown source from Poisson distributions and/or environmental sources.
NASA Astrophysics Data System (ADS)
Remetti, Romolo; Gandolfo, Giada; Lepore, Luigi; Cherubini, Nadia
2017-10-01
In the frame of Chemical, Biological, Radiological, and Nuclear defense European activities, the ENEA, the Italian National Agency for New Technologies, Energy and Sustainable Economic Development, is proposing the Neutron Active Interrogation system (NAI), a device designed to find transuranic-based Radioactive Dispersal Devices hidden inside suspected packages. It is based on Differential Die-Away time Analysis, an active neutron technique targeted in revealing the presence of fissile material through detection of induced fission neutrons. Several Monte Carlo simulations, carried out by MCNPX code, and the development of ad-hoc design methods, have led to the realization of a first prototype based on a 14 MeV d-t neutron generator coupled with a tailored moderating structure, and an array of helium-3 neutron detectors. The complete system is characterized by easy transportability, light weight, and real-time response. First results have shown device's capability to detect gram quantities of fissile materials.
Caldwell, John T.; Kunz, Walter E.; Cates, Michael R.; Franks, Larry A.
1985-01-01
Simultaneous photon and neutron interrogation of samples for the quantitative determination of total fissile nuclide and total fertile nuclide material present is made possible by the use of an electron accelerator. Prompt and delayed neutrons produced from resulting induced fissions are counted using a single detection system and allow the resolution of the contributions from each interrogating flux leading in turn to the quantitative determination sought. Detection limits for .sup.239 Pu are estimated to be about 3 mg using prompt fission neutrons and about 6 mg using delayed neutrons.
Caldwell, J.T.; Kunz, W.E.; Cates, M.R.; Franks, L.A.
1982-07-07
Simultaneous photon and neutron interrogation of samples for the quantitative determination of total fissile nuclide and total fertile nuclide material present is made possible by the use of an electron accelerator. Prompt and delayed neutrons produced from resulting induced fission are counted using a single detection system and allow the resolution of the contributions from each interrogating flux leading in turn to the quantitative determination sought. Detection limits for /sup 239/Pu are estimated to be about 3 mg using prompt fission neutrons and about 6 mg using delayed neutrons.
Communication methods, systems, apparatus, and devices involving RF tag registration
Burghard, Brion J [W. Richland, WA; Skorpik, James R [Kennewick, WA
2008-04-22
One technique of the present invention includes a number of Radio Frequency (RF) tags that each have a different identifier. Information is broadcast to the tags from an RF tag interrogator. This information corresponds to a maximum quantity of tag response time slots that are available. This maximum quantity may be less than the total number of tags. The tags each select one of the time slots as a function of the information and a random number provided by each respective tag. The different identifiers are transmitted to the interrogator from at least a subset of the RF tags.
Ultra-stable clock laser system development towards space applications.
Świerad, Dariusz; Häfner, Sebastian; Vogt, Stefan; Venon, Bertrand; Holleville, David; Bize, Sébastien; Kulosa, André; Bode, Sebastian; Singh, Yeshpal; Bongs, Kai; Rasel, Ernst Maria; Lodewyck, Jérôme; Le Targat, Rodolphe; Lisdat, Christian; Sterr, Uwe
2016-09-26
The increasing performance of optical lattice clocks has made them attractive for scientific applications in space and thus has pushed the development of their components including the interrogation lasers of the clock transitions towards being suitable for space, which amongst others requires making them more power efficient, radiation hardened, smaller, lighter as well as more mechanically stable. Here we present the development towards a space-compatible interrogation laser system for a strontium lattice clock constructed within the Space Optical Clock (SOC2) project where we have concentrated on mechanical rigidity and size. The laser reaches a fractional frequency instability of 7.9 × 10 -16 at 300 ms averaging time. The laser system uses a single extended cavity diode laser that gives enough power for interrogating the atoms, frequency comparison by a frequency comb and diagnostics. It includes fibre link stabilisation to the atomic package and to the comb. The optics module containing the laser has dimensions 60 × 45 × 8 cm 3 ; and the ultra-stable reference cavity used for frequency stabilisation with its vacuum system takes 30 × 30 × 30 cm 3 . The acceleration sensitivities in three orthogonal directions of the cavity are 3.6 × 10 -10 /g, 5.8 × 10 -10 /g and 3.1 × 10 -10 /g, where g ≈ 9.8 m/s 2 is the standard gravitational acceleration.
Interrogating Meanings of Work in Children's Literature
ERIC Educational Resources Information Center
Wieland, Stacey M. B.; Bauer, Janell C.
2015-01-01
In this article, Wieland and Bauer discuss a teaching activity that helps students understand how meanings of work (MOW) are socially constructed through commonplace texts: children's books. The activity helps students consider how children's books shape future workers' understandings of what work is, what kinds of work are most…
Rullan, Marc; Benzinger, Dirk; Schmidt, Gregor W; Milias-Argeitis, Andreas; Khammash, Mustafa
2018-05-17
Transcription is a highly regulated and inherently stochastic process. The complexity of signal transduction and gene regulation makes it challenging to analyze how the dynamic activity of transcriptional regulators affects stochastic transcription. By combining a fast-acting, photo-regulatable transcription factor with nascent RNA quantification in live cells and an experimental setup for precise spatiotemporal delivery of light inputs, we constructed a platform for the real-time, single-cell interrogation of transcription in Saccharomyces cerevisiae. We show that transcriptional activation and deactivation are fast and memoryless. By analyzing the temporal activity of individual cells, we found that transcription occurs in bursts, whose duration and timing are modulated by transcription factor activity. Using our platform, we regulated transcription via light-driven feedback loops at the single-cell level. Feedback markedly reduced cell-to-cell variability and led to qualitative differences in cellular transcriptional dynamics. Our platform establishes a flexible method for studying transcriptional dynamics in single cells. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.
Unpowered wireless generation and sensing of ultrasound
NASA Astrophysics Data System (ADS)
Huang, Haiying
2013-04-01
This paper presents a wireless ultrasound pitch-catch system that demonstrates the wireless generation and sensing of ultrasounds based on the principle of frequency conversion. The wireless ultrasound pitch-catch system consists of a wireless interrogator and two wireless ultrasound transducers. The wireless interrogator generates an ultrasound-modulated signal and a carrier signal, both at the microwave frequency, and transmits these two signals to the wireless ultrasound actuator using a pair of antennas. Upon receiving these two signals, the wireless ultrasound actuator recovers the ultrasound excitation signal using a passive mixer and then supplies it to a piezoelectric wafer sensor for ultrasound generation in the structure. For wireless ultrasound sensing, the frequency conversion process is reversed. The ultrasound sensing signal is up-converted to a microwave signal by the wireless ultrasound sensor and is recovered at the wireless interrogator using a homodyne receiver. To differentiate the wireless actuator from the wireless sensor, each wireless transducer is equipped with a narrowband microwave filter so that it only responds to the carrier frequency that matches the filter's operation bandwidth. The principle of operation of the wireless pitch-catch system, the hardware implementation, and the associated data processing algorithm to recover the ultrasound signal from the wirelessly received signal are described. The wirelessly acquired ultrasound signal is compared with those acquired using wired connection in both time and frequency domain.
The dynamic nature of interrogation.
Kelly, Christopher E; Miller, Jeaneé C; Redlich, Allison D
2016-06-01
Building on a substantial body of literature examining interrogation methods employed by police investigators and their relationship to suspect behaviors, we analyzed a sample of audio and video interrogation recordings of individuals suspected of serious violent crimes. Existing survey research has focused on the tactics reportedly used, at what rate, and under what conditions; observational studies detail which methods are actually employed. With a few notable exceptions, these foundational studies were static examinations of interrogation methods that documented the absence or presence of various approaches. In the present study, we cast interrogation as a dynamic phenomenon and code the recordings in 5-min intervals to examine how interrogation methods and suspect cooperation change over time. Employing the interrogation taxonomy framework, particularly 4 discrete domains-rapport and relationship building, emotion provocation, presentation of evidence, and confrontation/competition-we found that the emphasis of the domains varied across interrogations and were significantly different when suspects confessed versus when they denied involvement. In regression models, suspect cooperation was positively influenced by the rapport and relationship building domain, though it was negatively impacted by presentation of evidence and confrontation/competition. Moreover, we found that the negative effects of confrontation/competition on suspect cooperation lasted for up to 15 min. The implications of the findings for practice and future research include the benefits of a rapport-based approach, the deleterious effects of accusatorial methods, and the importance of studying when, not just if, certain interrogation techniques are employed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Chernenko, Tatyana; Buyukozturk, Fulden; Miljkovic, Milos; Carrier, Rebecca; Diem, Max; Amiji, Mansoor
2013-01-01
Active targeted delivery of nanoparticle-encapsulated agents to tumor cells in vivo is expected to enhance therapeutic effect with significantly less non-specific toxicity. Active targeting is based on surface modification of nanoparticles with ligands that bind with extracellular targets and enhance payload delivery in the cells. In this study, we have used label-free Raman micro-spectral analysis and kinetic modeling to study cellular interactions and intracellular delivery of C6-ceramide using a non-targeted and an epidermal growth factor receptor (EGFR) targeted biodegradable polymeric nano-delivery systems, in EGFR-expressing human ovarian adenocarcinoma (SKOV3) cells. The results show that EGFR peptide-modified nanoparticles were rapidly internalized in SKOV3 cells leading to significant intracellular accumulation as compared to non-specific uptake by the non-targeted nanoparticles. Raman micro-spectral analysis enables visualization and quantification of the carrier system, drug-load, and responses of the biological systems interrogated, without exogenous staining and labeling procedures. PMID:24298430
Lo, Shun Qiang; Koh, Dawn X. P.; Sng, Judy C. G.; Augustine, George J.
2015-01-01
Abstract. We describe an experimental approach that uses light to both control and detect neuronal activity in mouse barrel cortex slices: blue light patterned by a digital micromirror array system allowed us to photostimulate specific layers and columns, while a red-shifted voltage-sensitive dye was used to map out large-scale circuit activity. We demonstrate that such all-optical mapping can interrogate various circuits in somatosensory cortex by sequentially activating different layers and columns. Further, mapping in slices from whisker-deprived mice demonstrated that chronic sensory deprivation did not significantly alter feedforward inhibition driven by layer 5 pyramidal neurons. Further development of voltage-sensitive optical probes should allow this all-optical mapping approach to become an important and high-throughput tool for mapping circuit interactions in the brain. PMID:26158003
Design of a novel instrument for active neutron interrogation of artillery shells.
Bélanger-Champagne, Camille; Vainionpää, Hannes; Peura, Pauli; Toivonen, Harri; Eerola, Paula; Dendooven, Peter
2017-01-01
The most common explosives can be uniquely identified by measuring the elemental H/N ratio with a precision better than 10%. Monte Carlo simulations were used to design two variants of a new prompt gamma neutron activation instrument that can achieve this precision. The instrument features an intense pulsed neutron generator with precise timing. Measuring the hydrogen peak from the target explosive is especially challenging because the instrument itself contains hydrogen, which is needed for neutron moderation and shielding. By iterative design optimization, the fraction of the hydrogen peak counts coming from the explosive under interrogation increased from [Formula: see text]% to [Formula: see text]% (statistical only) for the benchmark design. In the optimized design variants, the hydrogen signal from a high-explosive shell can be measured to a statistics-only precision better than 1% in less than 30 minutes for an average neutron production yield of 109 n/s.
Design of a novel instrument for active neutron interrogation of artillery shells
Vainionpää, Hannes; Peura, Pauli; Toivonen, Harri; Eerola, Paula; Dendooven, Peter
2017-01-01
The most common explosives can be uniquely identified by measuring the elemental H/N ratio with a precision better than 10%. Monte Carlo simulations were used to design two variants of a new prompt gamma neutron activation instrument that can achieve this precision. The instrument features an intense pulsed neutron generator with precise timing. Measuring the hydrogen peak from the target explosive is especially challenging because the instrument itself contains hydrogen, which is needed for neutron moderation and shielding. By iterative design optimization, the fraction of the hydrogen peak counts coming from the explosive under interrogation increased from 53-7+7% to 74-10+8% (statistical only) for the benchmark design. In the optimized design variants, the hydrogen signal from a high-explosive shell can be measured to a statistics-only precision better than 1% in less than 30 minutes for an average neutron production yield of 109 n/s. PMID:29211773
Detection of tiny amounts of fissile materials in large-sized containers with radioactive waste
NASA Astrophysics Data System (ADS)
Batyaev, V. F.; Skliarov, S. V.
2018-01-01
The paper is devoted to non-destructive control of tiny amounts of fissile materials in large-sized containers filled with radioactive waste (RAW). The aim of this work is to model an active neutron interrogation facility for detection of fissile ma-terials inside NZK type containers with RAW and determine the minimal detectable mass of U-235 as a function of various param-eters: matrix type, nonuniformity of container filling, neutron gen-erator parameters (flux, pulse frequency, pulse duration), meas-urement time. As a result the dependence of minimal detectable mass on fissile materials location inside container is shown. Nonu-niformity of the thermal neutron flux inside a container is the main reason of the space-heterogeneity of minimal detectable mass in-side a large-sized container. Our experiments with tiny amounts of uranium-235 (<1 g) confirm the detection of fissile materials in NZK containers by using active neutron interrogation technique.
ERIC Educational Resources Information Center
Li, Hui; Jing, Mengguo; Wong, Eileen Chin Mei
2017-01-01
This study examined the development of and possible predictors of interrogative forms and functions in early childhood Mandarin. All the interrogatives drawn from the Early Child Mandarin Corpus (168 children 2;6, 3;6, 4;6, and 5;6) were analyzed. The main results indicated that (i) there were significant age effects in interrogative forms and…
Psychological Perspectives on Interrogation.
Vrij, Aldert; Meissner, Christian A; Fisher, Ronald P; Kassin, Saul M; Morgan, Charles A; Kleinman, Steven M
2017-11-01
Proponents of "enhanced interrogation techniques" in the United States have claimed that such methods are necessary for obtaining information from uncooperative terrorism subjects. In the present article, we offer an informed, academic perspective on such claims. Psychological theory and research shows that harsh interrogation methods are ineffective. First, they are likely to increase resistance by the subject rather than facilitate cooperation. Second, the threatening and adversarial nature of harsh interrogation is often inimical to the goal of facilitating the retrieval of information from memory and therefore reduces the likelihood that a subject will provide reports that are extensive, detailed, and accurate. Third, harsh interrogation methods make lie detection difficult. Analyzing speech content and eliciting verifiable details are the most reliable cues to assessing credibility; however, to elicit such cues subjects must be encouraged to provide extensive narratives, something that does not occur in harsh interrogations. Evidence is accumulating for the effectiveness of rapport-based information-gathering approaches as an alternative to harsh interrogations. Such approaches promote cooperation, enhance recall of relevant and reliable information, and facilitate assessments of credibility. Given the available evidence that torture is ineffective, why might some laypersons, policymakers, and interrogation personnel support the use of torture? We conclude our review by offering a psychological perspective on this important question.
Distributed cyberinfrastructure tools for automated data processing of structural monitoring data
NASA Astrophysics Data System (ADS)
Zhang, Yilan; Kurata, Masahiro; Lynch, Jerome P.; van der Linden, Gwendolyn; Sederat, Hassan; Prakash, Atul
2012-04-01
The emergence of cost-effective sensing technologies has now enabled the use of dense arrays of sensors to monitor the behavior and condition of large-scale bridges. The continuous operation of dense networks of sensors presents a number of new challenges including how to manage such massive amounts of data that can be created by the system. This paper reports on the progress of the creation of cyberinfrastructure tools which hierarchically control networks of wireless sensors deployed in a long-span bridge. The internet-enabled cyberinfrastructure is centrally managed by a powerful database which controls the flow of data in the entire monitoring system architecture. A client-server model built upon the database provides both data-provider and system end-users with secured access to various levels of information of a bridge. In the system, information on bridge behavior (e.g., acceleration, strain, displacement) and environmental condition (e.g., wind speed, wind direction, temperature, humidity) are uploaded to the database from sensor networks installed in the bridge. Then, data interrogation services interface with the database via client APIs to autonomously process data. The current research effort focuses on an assessment of the scalability and long-term robustness of the proposed cyberinfrastructure framework that has been implemented along with a permanent wireless monitoring system on the New Carquinez (Alfred Zampa Memorial) Suspension Bridge in Vallejo, CA. Many data interrogation tools are under development using sensor data and bridge metadata (e.g., geometric details, material properties, etc.) Sample data interrogation clients including those for the detection of faulty sensors, automated modal parameter extraction.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Walker, Randy M; Kopsick, Deborah A; Warren, Tracy A
One of the main components of the Environmental Protection Agency's (EPA) Clean Materials Program is to prevent the loss of radioactive materials through the use of tracking technologies. If a source is inadvertently lost or purposely abandoned or stolen, it is critical that the source be recovered before harm to the public or the environment occurs. Radio frequency identification (RFID) tagging on radioactive sources is a technology that can be operated in the active or passive mode, has a variety of frequencies available allowing for flexibility in use, is able to transmit detailed data and is discreet. The purpose ofmore » the joint DOE and EPA Radiological Source Tracking and Monitoring (RadSTraM) project is to evaluate the viability, effectiveness and scalability of RFID technology under a variety of transportation scenarios. The goal of the Phase II was to continue testing integrated RFID tag systems from various vendors for feasibility in tracking radioactive sealed sources which included the following performance objectives: 1. Validate the performance of RFID intelligent systems to monitor express air shipments of medical radioisotopes in the nationwide supply chain, 2. Quantify the reliability of these tracking systems with regards to probability of tag detection and operational reliability, 3. Determine if the implementation of these systems improves manpower effectiveness, and 4. Demonstrate that RFID tracking and monitoring of radioactive materials is ready for large scale deployment at the National level. For purposes of analysis, the test scenario employed in this study utilized the real world commerce supply chain process for radioactive medical isotopes to validate the performance of intelligent RFID tags. Three different RFID systems were assessed from a shipping and packaging perspective, included varied environmental conditions, varied commodities on board vehicles, temporary staging in shipping terminals using various commodities and normal transportation handling. We tracked 32 air express (AE) shipments from a medical radioisotope (MR) production facility in Boston, MA to ORNL in Oak Ridge, TN. Each RFID system was individually tested in Type A modified packaging with differing quantities of Phosphorus-32 (1,000 μci, 500 μci and 250 μci) for 16 shipments per system. Three of these shipments per system contained dry ice (9 total). An additional 16 shipments were tested that contained one tag from each system using Type A packaging without Phosphorus-32. Twelve of these shipments contained dry ice. RFID interrogators for each system were installed at four waypoints along the 1,000 mile shipping route from source to designation via air and surface. Each package was expected to be detected by its corresponding interrogator(s) at each way point. System A's overall probability of detection was 77 percent, System B's overall probability of detection was 20 percent and System C's overall probability was 75 percent. The presence of more than one RFID system in a shipment did not appear to have an effect on any of the three systems tested. However, no tests of significance could be performed because group sample sizes did not satisfy the standard binomial test-of-significance between independent samples. Preliminary analysis of the data using pair-wise comparison (in process) is expected to show some (possibly significant) differences due to packaging and the effects of dry ice on the tags. Phase II of the RadSTraM project verified that RFID tagging can be applied to the tracking and monitoring of medical radioisotope air express shipments. This study demonstrated that active RFID tagging systems can be feasibly integrated and scaled into the nation-wide supply chain to track and monitor medical radioisotopes.« less
Interrogating scarcity: how to think about ‘resource-scarce settings’
Schrecker, Ted
2013-01-01
The idea of resource scarcity permeates health ethics and health policy analysis in various contexts. However, health ethics inquiry seldom asks—as it should—why some settings are ‘resource-scarce’ and others not. In this article I describe interrogating scarcity as a strategy for inquiry into questions of resource allocation within a single political jurisdiction and, in particular, as an approach to the issue of global health justice in an interconnected world. I demonstrate its relevance to the situation of low- and middle-income countries (LMICs) with brief descriptions of four elements of contemporary globalization: trade agreements; the worldwide financial marketplace and capital flight; structural adjustment; imperial geopolitics and foreign policy. This demonstration involves not only health care, but also social determinants of health. Finally, I argue that interrogating scarcity provides the basis for a new, critical approach to health policy at the interface of ethics and the social sciences, with specific reference to market fundamentalism as the value system underlying contemporary globalization. PMID:22899597
Interrogating scarcity: how to think about 'resource-scarce settings'.
Schrecker, Ted
2013-07-01
The idea of resource scarcity permeates health ethics and health policy analysis in various contexts. However, health ethics inquiry seldom asks-as it should-why some settings are 'resource-scarce' and others not. In this article I describe interrogating scarcity as a strategy for inquiry into questions of resource allocation within a single political jurisdiction and, in particular, as an approach to the issue of global health justice in an interconnected world. I demonstrate its relevance to the situation of low- and middle-income countries (LMICs) with brief descriptions of four elements of contemporary globalization: trade agreements; the worldwide financial marketplace and capital flight; structural adjustment; imperial geopolitics and foreign policy. This demonstration involves not only health care, but also social determinants of health. Finally, I argue that interrogating scarcity provides the basis for a new, critical approach to health policy at the interface of ethics and the social sciences, with specific reference to market fundamentalism as the value system underlying contemporary globalization.
Li, Hui; Jing, Mengguo; Wong, Eileen Chin Mei
2017-01-01
This study examined the development of and possible predictors of interrogative forms and functions in early childhood Mandarin. All the interrogatives drawn from the Early Child Mandarin Corpus (168 children 2;6, 3;6, 4;6, and 5;6) were analyzed. The main results indicated that (i) there were significant age effects in interrogative forms and functions, with the periods between the ages of 3;6 and 4;6 and between the ages of 2;6 and 3;6 being critical in the early acquisition of interrogative forms and functions, respectively; (ii) the form-function preference was verified, with wh-questions being primarily used to seek information (RfI), and intonation/echo and rhetorical questions being used to request action (RfA); (iii) more than half (59·5%) of the Mandarin interrogatives were used for RfI, whereas only 38·9% of them were used for RfA; and (iv) age, TV viewing time, and parent-child conversation time were the significant predictors of interrogative development.
Magnetic Field Response Measurement Acquisition System
NASA Technical Reports Server (NTRS)
Woodard, Stanley E.; Taylor, Bryant D.; Shams, Qamar A.; Fox, Robert L.
2005-01-01
A measurement acquisition method that alleviates many shortcomings of traditional measurement systems is presented in this paper. The shortcomings are a finite number of measurement channels, weight penalty associated with measurements, electrical arcing, wire degradations due to wear or chemical decay and the logistics needed to add new sensors. The key to this method is the use of sensors designed as passive inductor-capacitor circuits that produce magnetic field responses. The response attributes correspond to states of physical properties for which the sensors measure. A radio frequency antenna produces a time-varying magnetic field used to power the sensor and receive the magnetic field response of the sensor. An interrogation system for discerning changes in the sensor response is presented herein. Multiple sensors can be interrogated using this method. The method eliminates the need for a data acquisition channel dedicated to each sensor. Methods of developing magnetic field response sensors and the influence of key parameters on measurement acquisition are discussed.
A Web Architecture to Geographically Interrogate CHIRPS Rainfall and eMODIS NDVI for Land Use Change
NASA Technical Reports Server (NTRS)
Burks, Jason E.; Limaye, Ashutosh
2014-01-01
Monitoring of rainfall and vegetation over the continent of Africa is important for assessing the status of crop health and agriculture, along with long-term changes in land use change. These issues can be addressed through examination of long-term precipitation (rainfall) data sets and remote sensing of land surface vegetation and land use types. Two products have been used previously to address these goals: the Climate Hazard Group Infrared Precipitation with Stations (CHIRPS) rainfall data, and multi-day composites of Normalized Difference Vegetation Index (NDVI) from the USGS eMODIS product. Combined, these are very large data sets that require unique tools and architecture to facilitate a variety of data analysis methods or data exploration by the end user community. To address these needs, a web-enabled system has been developed to allow end-users to interrogate CHIRPS rainfall and eMODIS NDVI data over the continent of Africa. The architecture allows end-users to use custom defined geometries, or the use of predefined political boundaries in their interrogation of the data. The massive amount of data interrogated by the system allows the end-users with only a web browser to extract vital information in order to investigate land use change and its causes. The system can be used to generate daily, monthly and yearly averages over a geographical area and range of dates of interest to the user. It also provides analysis of trends in precipitation or vegetation change for times of interest. The data provided back to the end-user is displayed in graphical form and can be exported for use in other, external tools. The development of this tool has significantly decreased the investment and requirements for end-users to use these two important datasets, while also allowing the flexibility to the end-user to limit the search to the area of interest.
Lee, Hwi Don; Jung, Eun Joo; Jeong, Myung Yung; Chen, Zhongping; Kim, Chang-Seok
2014-01-01
A novel linearized interrogation method is presented for a Fourier domain mode-locked (FDML) fiber Bragg grating (FBG) sensor system. In a high speed regime over several tens of kHz modulations, a sinusoidal wave is available to scan the center wavelength of an FDML wavelength-swept laser, instead of a conventional triangular wave. However, sinusoidal wave modulation suffers from an exaggerated non-uniform wavelength-spacing response in demodulating the time-encoded parameter to the absolute wavelength. In this work, the calibration signal from a polarization-maintaining fiber Sagnac interferometer shares the FDML wavelength-swept laser for FBG sensors to convert the time-encoded FBG signal to the wavelength-encoded uniform-spacing signal. PMID:24489440
Content analysis to detect high stress in oral interviews and text documents
NASA Technical Reports Server (NTRS)
Thirumalainambi, Rajkumar (Inventor); Jorgensen, Charles C. (Inventor)
2012-01-01
A system of interrogation to estimate whether a subject of interrogation is likely experiencing high stress, emotional volatility and/or internal conflict in the subject's responses to an interviewer's questions. The system applies one or more of four procedures, a first statistical analysis, a second statistical analysis, a third analysis and a heat map analysis, to identify one or more documents containing the subject's responses for which further examination is recommended. Words in the documents are characterized in terms of dimensions representing different classes of emotions and states of mind, in which the subject's responses that manifest high stress, emotional volatility and/or internal conflict are identified. A heat map visually displays the dimensions manifested by the subject's responses in different colors, textures, geometric shapes or other visually distinguishable indicia.
Negotiate Instead of Interrogate-Get Better Results from Interrogations Through Negotiation
2009-04-01
and ideas. Incorporation of negotiation theory and practice into interrogation settings will yield better results. The goal of this paper is to... practice or theory. The end result is a new way to look at interrogations and create a paradigm shift. Through a compare and contrast methodology, this...tried and true practice , why were the two concepts never combined before? First, we must clarify some definitions and terms. There are two main
Sherlekar, Amrita L; Janssen, Abbey; Siehr, Meagan S; Koo, Pamela K; Caflisch, Laura; Boggess, May; Lints, Robyn
2013-01-01
Mating behaviors in simple invertebrate model organisms represent tractable paradigms for understanding the neural bases of sex-specific behaviors, decision-making and sensorimotor integration. However, there are few examples where such neural circuits have been defined at high resolution or interrogated. Here we exploit the simplicity of the nematode Caenorhabditis elegans to define the neural circuits underlying the male's decision to initiate mating in response to contact with a mate. Mate contact is sensed by male-specific sensilla of the tail, the rays, which subsequently induce and guide a contact-based search of the hermaphrodite's surface for the vulva (the vulva search). Atypically, search locomotion has a backward directional bias so its implementation requires overcoming an intrinsic bias for forward movement, set by activity of the sex-shared locomotory system. Using optogenetics, cell-specific ablation- and mutant behavioral analyses, we show that the male makes this shift by manipulating the activity of command cells within this sex-shared locomotory system. The rays control the command interneurons through the male-specific, decision-making interneuron PVY and its auxiliary cell PVX. Unlike many sex-shared pathways, PVY/PVX regulate the command cells via cholinergic, rather than glutamatergic transmission, a feature that likely contributes to response specificity and coordinates directional movement with other cholinergic-dependent motor behaviors of the mating sequence. PVY/PVX preferentially activate the backward, and not forward, command cells because of a bias in synaptic inputs and the distribution of key cholinergic receptors (encoded by the genes acr-18, acr-16 and unc-29) in favor of the backward command cells. Our interrogation of male neural circuits reveals that a sex-specific response to the opposite sex is conferred by a male-specific pathway that renders subordinate, sex-shared motor programs responsive to mate cues. Circuit modifications of these types may make prominent contributions to natural variations in behavior that ultimately bring about speciation.
Sherlekar, Amrita L.; Janssen, Abbey; Siehr, Meagan S.; Koo, Pamela K.; Caflisch, Laura; Boggess, May; Lints, Robyn
2013-01-01
Background Mating behaviors in simple invertebrate model organisms represent tractable paradigms for understanding the neural bases of sex-specific behaviors, decision-making and sensorimotor integration. However, there are few examples where such neural circuits have been defined at high resolution or interrogated. Methodology/Principal Findings Here we exploit the simplicity of the nematode Caenorhabditis elegans to define the neural circuits underlying the male’s decision to initiate mating in response to contact with a mate. Mate contact is sensed by male-specific sensilla of the tail, the rays, which subsequently induce and guide a contact-based search of the hermaphrodite’s surface for the vulva (the vulva search). Atypically, search locomotion has a backward directional bias so its implementation requires overcoming an intrinsic bias for forward movement, set by activity of the sex-shared locomotory system. Using optogenetics, cell-specific ablation- and mutant behavioral analyses, we show that the male makes this shift by manipulating the activity of command cells within this sex-shared locomotory system. The rays control the command interneurons through the male-specific, decision-making interneuron PVY and its auxiliary cell PVX. Unlike many sex-shared pathways, PVY/PVX regulate the command cells via cholinergic, rather than glutamatergic transmission, a feature that likely contributes to response specificity and coordinates directional movement with other cholinergic-dependent motor behaviors of the mating sequence. PVY/PVX preferentially activate the backward, and not forward, command cells because of a bias in synaptic inputs and the distribution of key cholinergic receptors (encoded by the genes acr-18, acr-16 and unc-29) in favor of the backward command cells. Conclusion/Significance Our interrogation of male neural circuits reveals that a sex-specific response to the opposite sex is conferred by a male-specific pathway that renders subordinate, sex-shared motor programs responsive to mate cues. Circuit modifications of these types may make prominent contributions to natural variations in behavior that ultimately bring about speciation. PMID:23577128
Diagnostic yield of device interrogation in the evaluation of syncope in an elderly population.
D'Angelo, Robert N; Pickett, Christopher C
2017-06-01
Device interrogation has become a standard part of the syncope evaluation for patients admitted with permanent pacemakers (PPM) or implantable cardiac defibrillators (ICD), although few studies have shown interrogation yields clinically useful data. The purpose of this study is to determine the diagnostic yield of device interrogation as well as other commonly performed tests in the workup of unexplained syncope in patients with previously implanted PPMs or ICDs. We retrospectively reviewed records of 88 patients admitted to our medical center for syncope with previously implanted pacemakers between January 1, 2005 and January 1, 2015 using ICD-9 billing data. Pacemaker interrogation demonstrated an arrhythmia as the cause for syncope in 4 patients (4%) and evidence of device failure secondary to perforation in 1 patient (1%). The cause of syncope was unknown in 34 patients (39%). Orthostatic hypotension was the most commonly identified cause of syncope (26%), followed by vasovagal syncope (13%), autonomic dysfunction (5%), ventricular arrhythmia (3%), atrial arrhythmia (2%), congestive heart failure (2%), stroke (2%), and other less common causes (8%). History was the most important determinant of syncope (36%), followed by orthostatic vital signs (14%), device interrogations (4%), head CT (2%), and transthoracic echocardiogram (1%). Device interrogation is rarely useful for elucidating a cause of syncope without concerning physical exam, telemetry, or EKG findings. Interrogation may occasionally yield paroxysmal arrhythmias responsible for syncopal episode, but these rarely alter clinical outcomes. Interrogation appears to be more useful in patients with syncope after recent device placement. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
Dose profile modeling of Idaho National Laboratory's active neutron interrogation laboratory.
Chichester, D L; Seabury, E H; Zabriskie, J M; Wharton, J; Caffrey, A J
2009-06-01
A new laboratory has been commissioned at Idaho National Laboratory for performing active neutron interrogation research and development. The facility is designed to provide radiation shielding for deuterium-tritium (DT) fusion (14.1 MeV) neutron generators (2 x 10(8) n/s), deuterium-deuterium (DD) fusion (2.5 MeV) neutron generators (1 x 10(7) n/s), and (252)Cf spontaneous fission neutron sources (6.96 x 10(7) n/s, 30 microg). Shielding at the laboratory is comprised of modular concrete shield blocks 0.76 m thick with tongue-in-groove features to prevent radiation streaming, arranged into one small and one large test vault. The larger vault is designed to allow operation of the DT generator and has walls 3.8m tall, an entrance maze, and a fully integrated electrical interlock system; the smaller test vault is designed for (252)Cf and DD neutron sources and has walls 1.9 m tall and a simple entrance maze. Both analytical calculations and numerical simulations were used in the design process for the building to assess the performance of the shielding walls and to ensure external dose rates are within required facility limits. Dose rate contour plots have been generated for the facility to visualize the effectiveness of the shield walls and entrance mazes and to illustrate the spatial profile of the radiation dose field above the facility and the effects of skyshine around the vaults.
DOSE PROFILE MODELING OF IDAHO NATIONAL LABORATORY’S ACTIVE NEUTRON INTERROGATION TEST FACILITY
DOE Office of Scientific and Technical Information (OSTI.GOV)
D. L. Chichester; E. H. Seabury; J. M. Zabriskie
2009-06-01
A new research and development laboratory has been commissioned at Idaho National Laboratory for performing active neutron interrogation research and development. The facility is designed to provide radiation shielding for DT fusion (14.1 MeV) neutron generators (2 x 108 neutrons per second), DD fusion (2.5 MeV) neutron generators (up to 2 x 106 neutrons per second), and 252Cf spontaneous fission neutron sources (6.7 x 107 neutrons per second, 30 micrograms). Shielding at the laboratory is comprised of modular concrete shield blocks 0.76 m thick with tongue-in-groove features to prevent radiation streaming, arranged into one small and one large test vault.more » The larger vault is designed to allow operation of the DT generator and has walls 3.8 m tall, an entrance maze, and a fully integrated electrical interlock system; the smaller test vault is designed for 252Cf and DD neutron sources and has walls 1.9 m tall and a simple entrance maze. Both analytical calculations and numerical simulations were used in the design process for the building to assess the performance of the shielding walls and to ensure external dose rates are within required facility limits. Dose rate contour plots have been generated for the facility to visualize the effectiveness of the shield wall and entrance maze and to illustrate the spatial profile of the radiation dose field above the facility and the effects of skyshine around the vaults.« less
Interrogative suggestibility in patients with conversion disorders.
Foong, J; Lucas, P A; Ron, M A
1997-09-01
We tested the hypothesis that increased interrogative suggestibility may contribute to the shaping and maintaining of conversions symptoms. Interrogative suggestibility was measured in 12 patients with conversion disorder and 10 control patients with confirmed neurological disease matched for age, premorbid intelligence, and as closely as possible in terms of their neurological symptoms to the patients with conversion disorder. Our observations do not support the contention that individual differences in interrogative suggestibility are of importance in the etiology of conversion disorders.
Asking Questions: Will Army Tactical Interrogation be Ready for War?
1986-12-17
still never answer the basic question: "Is there enough?" It is the interrogator portion of this question that this paper will address to provide a...tenative answer for the near to midrange future. Section II of this paper will examine the historical 2 AA 4 importance of interrogator derived...the former that this paper will concern itself. In addition to interrogators, there have historically existed, and there continue to exist today (almost
ERIC Educational Resources Information Center
Long, Trisha Wies
2017-01-01
Adolescents are often disengaged in the learning process, being more focused on social media and self-interest than classroom content. Full circling is a process that can be used to help students collaboratively engage in learning and actively reflect on historical events--especially those that are under reported in history books. In the present…
ERIC Educational Resources Information Center
Peterson, David Kent
2014-01-01
The following study is an extended ethnographic case study of a "black intellectual insurgency" within the predominantly white space of the U.S. intercollegiate policy debate activity. A growing number of black students are entering the debate activity and insisting that "whiteness" be confronted and interrogated and that…
Web-Based Tools for Modelling and Analysis of Multivariate Data: California Ozone Pollution Activity
ERIC Educational Resources Information Center
Dinov, Ivo D.; Christou, Nicolas
2011-01-01
This article presents a hands-on web-based activity motivated by the relation between human health and ozone pollution in California. This case study is based on multivariate data collected monthly at 20 locations in California between 1980 and 2006. Several strategies and tools for data interrogation and exploratory data analysis, model fitting…
Zhang, Huixin; Hong, Yingping; Liang, Ting; Zhang, Hairui; Tan, Qiulin; Xue, Chenyang; Liu, Jun; Zhang, Wendong; Xiong, Jijun
2015-01-01
A wireless passive pressure measurement system for an 800 °C high-temperature environment is proposed and the impedance variation caused by the mutual coupling between a read antenna and a LC resonant sensor is analyzed. The system consists of a ceramic-based LC resonant sensor, a readout device for impedance phase interrogation, heat insulating material, and a composite temperature-pressure test platform. Performances of the pressure sensor are measured by the measurement system sufficiently, including pressure sensitivity at room temperature, zero drift from room temperature to 800 °C, and the pressure sensitivity under the 800 °C high temperature environment. The results show that the linearity of sensor is 0.93%, the repeatability is 6.6%, the hysteretic error is 1.67%, and the sensor sensitivity is 374 KHz/bar. The proposed measurement system, with high engineering value, demonstrates good pressure sensing performance in a high temperature environment. PMID:25690546
Development and application of a particle image velocimeter for high-speed flows
NASA Astrophysics Data System (ADS)
Molezzi, M. J.; Dutton, J. C.
1992-01-01
A particle image velocimetry (PIV) system has been developed for use in high-speed separated air flows. The image acquisition system uses two 550 mJ/pulse Nd:YAG lasers and is fully controlled by a host Macintosh computer. The interrogation system is also Macintosh-based and performs interrogations at approximately 2.3 sec/spot and 4.0 sec/spot when using the Young's fringe and autocorrelation methods, respectively. The system has been proven in preliminary experiments using known-displacement simulated PIV photographs and a simple axisymmetric jet flow. Further results have been obtained in a transonic wind tunnel operating at Mach 0.4 to 0.5 (135 m/s to 170 m/s). PIV experiments were done with an empty test section to provide uniform flow data for comparison with pressure and LDV data, then with a two-dimensional base model, revealing features of the von Karman vortex street wake and underlying small scale turbulence.
Toward multi-area distributed network of implanted neural interrogators
NASA Astrophysics Data System (ADS)
Powell, Marc P.; Hou, Xiaoxiao; Galligan, Craig; Ashe, Jeffrey; Borton, David A.
2017-08-01
As we aim to improve our understanding of the brain, it is critical that researchers have simultaneous multi-area, large-scale access to the brain. Information processing in the brain occurs through close and distant coupling of functional sub-domains, as opposed to within isolated single neurons. However, commercially available neural interfaces capable of sensing electrophysiology of single neurons, currently allow access to only a small, mm3 volume of cortical cells, are not scalable to recording from orders of magnitude more neurons, and leverage bulky, skull mounted hardware and cabling sensitive to relative movements of the skull and brain. In this work, we propose a system capable of recording from many individual distributed neural interrogator nodes, untethered from any external electronics. Using an array of epidural inductive coils to wirelessly power the implanted electronics, the system is intended to be agnostic to the surgical placement of any individual node. Here, we demonstrate the ability to transmit nearly 15mW of power with greater than 50% power transfer efficiency, benchtop testing of individual subcircuit system components showing successful digitization of neural signals, and wireless transmission currently supporting a data rate of 3.84Mbps. We leverage a software defined radio based RF receiver to demodulate the data which can be stored in memory for later retrieval. Finally, we introduce a packaging technology capable of isolating active electronics from the surrounding tissue while providing capability for electrical feed-through assemblies for external neural interfacing. We expect, based on the presented preliminary findings, that the system can be integrated into a platform technology for the study of the intricate interactions between cortical domains.
NASA Astrophysics Data System (ADS)
Lee, Sangkyu
Illicit trafficking and smuggling of radioactive materials and special nuclear materials (SNM) are considered as one of the most important recent global nuclear threats. Monitoring the transport and safety of radioisotopes and SNM are challenging due to their weak signals and easy shielding. Great efforts worldwide are focused at developing and improving the detection technologies and algorithms, for accurate and reliable detection of radioisotopes of interest in thus better securing the borders against nuclear threats. In general, radiation portal monitors enable detection of gamma and neutron emitting radioisotopes. Passive or active interrogation techniques, present and/or under the development, are all aimed at increasing accuracy, reliability, and in shortening the time of interrogation as well as the cost of the equipment. Equally important efforts are aimed at advancing algorithms to process the imaging data in an efficient manner providing reliable "readings" of the interiors of the examined volumes of various sizes, ranging from cargos to suitcases. The main objective of this thesis is to develop two synergistic algorithms with the goal to provide highly reliable - low noise identification of radioisotope signatures. These algorithms combine analysis of passive radioactive detection technique with active interrogation imaging techniques such as gamma radiography or muon tomography. One algorithm consists of gamma spectroscopy and cosmic muon tomography, and the other algorithm is based on gamma spectroscopy and gamma radiography. The purpose of fusing two detection methodologies per algorithm is to find both heavy-Z radioisotopes and shielding materials, since radionuclides can be identified with gamma spectroscopy, and shielding materials can be detected using muon tomography or gamma radiography. These combined algorithms are created and analyzed based on numerically generated images of various cargo sizes and materials. In summary, the three detection methodologies are fused into two algorithms with mathematical functions providing: reliable identification of radioisotopes in gamma spectroscopy; noise reduction and precision enhancement in muon tomography; and the atomic number and density estimation in gamma radiography. It is expected that these new algorithms maybe implemented at portal scanning systems with the goal to enhance the accuracy and reliability in detecting nuclear materials inside the cargo containers.
The airborne laser ranging system, its capabilities and applications
NASA Technical Reports Server (NTRS)
Kahn, W. D.; Degnan, J. J.; Englar, T. S., Jr.
1982-01-01
The airborne laser ranging system is a multibeam short pulse laser ranging system on board an aircraft. It simultaneously measures the distances between the aircraft and six laser retroreflectors (targets) deployed on the Earth's surface. The system can interrogate over 100 targets distributed over an area of 25,000 sq, kilometers in a matter of hours. Potentially, a total of 1.3 million individual range measurements can be made in a six hour flight. The precision of these range measurements is approximately + or - 1 cm. These measurements are used in procedure which is basically an extension of trilateration techniques to derive the intersite vector between the laser ground targets. By repeating the estimation of the intersite vector, strain and strain rate errors can be estimated. These quantities are essential for crustal dynamic studies which include determination and monitoring of regional strain in the vicinity of active fault zones, land subsidence, and edifice building preceding volcanic eruptions.
The API 120: A portable neutron generator for the associated particle technique
NASA Astrophysics Data System (ADS)
Chichester, D. L.; Lemchak, M.; Simpson, J. D.
2005-12-01
The API 120 is a lightweight, portable neutron generator for active neutron interrogation (ANI) field work exploiting the associated particle technique. It incorporates a small sealed-tube accelerator, an all digital control system with smart on-board diagnostics, a simple platform-independent control interface and a comprehensive safety interlock philosophy with provisions for wireless control. The generator operates in a continuous output mode using either the D-D or D-T fusion reactions. To register the helium ion associated with fusion, the system incorporates a high resolution fiber optic imaging plate that may be coated with one of several different phosphors. The ion beam on the target measures less than 2 mm in diameter, thus making the system suitable for multi-dimensional imaging. The system is rated at 1E7 n/s for over 1000 h although higher yields are possible. The overall weight is 12 kg; power consumption is less than 50 W.
Cui, Jiwen; Hu, Yang; Feng, Kunpeng; Li, Junying; Tan, Jiubin
2015-01-01
In this paper, a high resolution and response speed interrogation method based on a reflective-matched Fiber Bragg Grating (FBG) scheme is investigated in detail. The nonlinear problem of the reflective-matched FBG sensing interrogation scheme is solved by establishing and optimizing the mathematical model. A mechanical adjustment to optimize the interrogation method by tuning the central wavelength of the reference FBG to improve the stability and anti-temperature perturbation performance is investigated. To satisfy the measurement requirements of optical and electric signal processing, a well- designed acquisition circuit board is prepared, and experiments on the performance of the interrogation method are carried out. The experimental results indicate that the optical power resolution of the acquisition circuit border is better than 8 pW, and the stability of the interrogation method with the mechanical adjustment can reach 0.06%. Moreover, the nonlinearity of the interrogation method is 3.3% in the measurable range of 60 pm; the influence of temperature is significantly reduced to 9.5%; the wavelength resolution and response speed can achieve values of 0.3 pm and 500 kHz, respectively. PMID:26184195
Cui, Jiwen; Hu, Yang; Feng, Kunpeng; Li, Junying; Tan, Jiubin
2015-07-08
In this paper, a high resolution and response speed interrogation method based on a reflective-matched Fiber Bragg Grating (FBG) scheme is investigated in detail. The nonlinear problem of the reflective-matched FBG sensing interrogation scheme is solved by establishing and optimizing the mathematical model. A mechanical adjustment to optimize the interrogation method by tuning the central wavelength of the reference FBG to improve the stability and anti-temperature perturbation performance is investigated. To satisfy the measurement requirements of optical and electric signal processing, a well- designed acquisition circuit board is prepared, and experiments on the performance of the interrogation method are carried out. The experimental results indicate that the optical power resolution of the acquisition circuit border is better than 8 pW, and the stability of the interrogation method with the mechanical adjustment can reach 0.06%. Moreover, the nonlinearity of the interrogation method is 3.3% in the measurable range of 60 pm; the influence of temperature is significantly reduced to 9.5%; the wavelength resolution and response speed can achieve values of 0.3 pm and 500 kHz, respectively.
Negri, Lucas; Nied, Ademir; Kalinowski, Hypolito; Paterno, Aleksander
2011-01-01
This paper presents a benchmark for peak detection algorithms employed in fiber Bragg grating spectrometric interrogation systems. The accuracy, precision, and computational performance of currently used algorithms and those of a new proposed artificial neural network algorithm are compared. Centroid and gaussian fitting algorithms are shown to have the highest precision but produce systematic errors that depend on the FBG refractive index modulation profile. The proposed neural network displays relatively good precision with reduced systematic errors and improved computational performance when compared to other networks. Additionally, suitable algorithms may be chosen with the general guidelines presented. PMID:22163806
Active Wireless System for Structural Health Monitoring Applications.
Perera, Ricardo; Pérez, Alberto; García-Diéguez, Marta; Zapico-Valle, José Luis
2017-12-11
The use of wireless sensors in Structural Health Monitoring (SHM) has increased significantly in the last years. Piezoelectric-based lead zirconium titanate (PZT) sensors have been on the rise in SHM due to their superior sensing abilities. They are applicable in different technologies such as electromechanical impedance (EMI)-based SHM. This work develops a flexible wireless smart sensor (WSS) framework based on the EMI method using active sensors for full-scale and autonomous SHM. In contrast to passive sensors, the self-sensing properties of the PZTs allow interrogating with or exciting a structure when desired. The system integrates the necessary software and hardware within a service-oriented architecture approach able to provide in a modular way the services suitable to satisfy the key requirements of a WSS. The framework developed in this work has been validated on different experimental applications. Initially, the reliability of the EMI method when carried out with the proposed wireless sensor system is evaluated by comparison with the wireless counterpart. Afterwards, the performance of the system is evaluated in terms of software stability and reliability of functioning.
Thermal Neutron Radiography using a High-flux Compact Neutron Generator
NASA Astrophysics Data System (ADS)
Taylor, Michael; Sengbusch, Evan; Seyfert, Chris; Moll, Eli; Radel, Ross
A novel neutron imaging system has been designed and constructed by Phoenix Nuclear Labs to investigate specimens when conventional X-ray imaging will not suffice. A first-generation electronic neutron generator is actively being used by the United States Army and is coupled with activation films for neutron radiography to inspect munitions and other critical defence and aerospace components. A second-generation system has been designed to increase the total neutron output from an upgraded gaseous deuterium target to 5×1011 DD n/s, generating higher neutron flux at the imaging plane and dramatically reducing interrogation time, while maintaining high spatial resolution and low geometric unsharpness. A description of the neutron generator and imaging system, including the beamline, target and detector platform, is given in this paper. State of the art neutron moderators, collimators and imaging detector components are also discussed in the context of increasing specimen throughput and optimizing image quality. Neutron radiographs captured with the neutron radiography system will be further compared against simulated images using the MCNP nuclear simulation code.
Cache coherency without line exclusivity in MP systems having store-in caches
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pomerene, J.H.; Puzak, T.R.; Rechtschaffen, R.N.
1983-11-01
By modifying the function of the storage control unit, a multiprocessor (MP) system having store-in caches is enabled to operate with the same versatility as an MP system having store-through caches, thereby eliminating the requirement for line exclusivity and greatly reducing the occurrence of cross-interrogates.
Characterization Test Report for the Mnemonics-UCS Wireless Surface Acoustic Wave Sensor System
NASA Technical Reports Server (NTRS)
Duncan, Joshua J.; Youngquist, Robert C.
2013-01-01
The scope of this testing includes the Surface Acoustic Wave Sensor System delivered to KSC: two interrogator (transceiver) systems, four temperature sensors, with wooden mounting blocks, two antennas, two power supplies, network cables, and analysis software. Also included are a number of additional temperature sensors and newly-developed hydrogen sensors
Portable fluorescence lifetime spectroscopy system for in-situ interrogation of biological tissues.
Saito Nogueira, Marcelo; Cosci, Alessandro; Teixeira Rosa, Ramon Gabriel; Salvio, Ana Gabriela; Pratavieira, Sebastião; Kurachi, Cristina
2017-10-01
Fluorescence spectroscopy and lifetime techniques are potential methods for optical diagnosis and characterization of biological tissues with an in-situ, fast, and noninvasive interrogation. Several diseases may be diagnosed due to differences in the fluorescence spectra of targeted fluorophores, when, these spectra are similar, considering steady-state fluorescence, others may be detected by monitoring their fluorescence lifetime. Despite this complementarity, most of the current fluorescence lifetime systems are not robust and portable, and not being feasible for clinical applications. We describe the assembly of a fluorescence lifetime spectroscopy system in a suitcase, its characterization, and validation with clinical measurements of skin lesions. The assembled system is all encased and robust, maintaining its mechanical, electrical, and optical stability during transportation, and is feasible for clinical measurements. The instrument response function measured was about 300 ps, and the system is properly calibrated. At the clinical study, the system showed to be reliable, and the achieved spectroscopy results support its potential use as an auxiliary tool for skin diagnostics. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).
Enhanced optical discrimination system based on switchable retroreflective films
NASA Astrophysics Data System (ADS)
Schultz, Phillip; Heikenfeld, Jason
2016-04-01
Reported herein is the design, characterization, and demonstration of a laser interrogation and response optical discrimination system based on large-area corner-cube retroreflective films. The switchable retroreflective films use light-scattering liquid crystal to modulate retroreflected intensity. The system can operate with multiple wavelengths (visible to infrared) and includes variable divergence optics for irradiance adjustments and ease of system alignment. The electronic receiver and switchable retroreflector offer low-power operation (<4 mW standby) on coin cell batteries with rapid interrogation to retroreflected signal reception response times (<15 ms). The entire switchable retroreflector film is <1 mm thick and is flexible for optimal placement and increased angular response. The system was demonstrated in high ambient lighting conditions (daylight, 18k lux) with a visible 10-mW output 635-nm source out to a distance of 400 m (naked eye detection). Nighttime demonstrations were performed using a 1.5-mW, 850-nm infrared laser diode out to a distance of 400 m using a night vision camera. This system could have tagging and conspicuity applications in commercial or military settings.
2017-03-01
research design flaw, “the pretesting process may have affected the ability to correctly classify subjects on the post - test ,” they conclude their results...Value Detainee Interrogation Group (HIG) in response to the highly publicized post -9/11 interrogation tactics the United States used on terrorist...in response to the highly publicized post -9/11 interrogation tactics the United States used on terrorist suspects.13 Part of the group’s mission was
Hand-Held Units for Short-Range Wireless Biotelemetry
NASA Technical Reports Server (NTRS)
Miranda, Felix A.; Simons, Rainee N.
2008-01-01
Special-purpose hand-held radiotransceiver units have been proposed as means of short-range radio powering and interrogation of surgically implanted microelectromechanical sensors and actuators. These units are based partly on the same principles as those of the units described in "Printed Multi- Turn Loop Antennas for RF Biotelemetry" (LEW-17879-1), NASA Tech Briefs, Vol. 31, No. 6 (June 2007), page 48. Like the previously reported units, these units would make it unnecessary to have wire connections between the implanted devices and the external equipment used to activate and interrogate them. Like a unit of the previously reported type, a unit of the type now proposed would include a printed-circuit antenna on a dielectric substrate. The antenna circuitry would include integrated surface-mount inductors for impedance tuning. Circuits for processing the signals transmitted and received by the antenna would be included on the substrate. During operation, the unit would be positioned near (but not in electrical contact with) a human subject, in proximity to a microelectromechanical sensor or actuator that has been surgically implanted in the subject. It has been demonstrated that significant electromagnetic coupling with an implanted device could be established at a distance of as much as 4 in. (.10 cm). During operation in the interrogation mode, the antenna of the unit would receive a radio telemetry signal transmitted by the surgically implanted device. The antenna substrate would have dimensions of approximately 3.25 by 3.75 inches (approximately 8.3 by 9.5 cm). The substrate would have a thickness of the order of 30 mils (of the order of a somewhat less than a millimeter). The substrate would be made of low-radiofrequency- loss dielectric material that could be, for example, fused quartz, alumina, or any of a number of commercially available radio-frequency dielectric composite materials. The antenna conductors would typically be made of copper or a combination of chromium and gold. The choice of metal and the thickness of the metal layer(s) would depend on the choice of substrate material. For example, on a quartz or alumina substrate, one would typically use a layer of chromium 150 A thick and a layer of gold 2 m thick. The proposed units and the implanted devices that they would interrogate or activate would be inherently safe to use. They would operate at low radiated-power levels for short interrogation times (typically, milliseconds). Hence, there would be little local heating of tissues surrounding the implanted devices and little absorption of radio energy by such sensitive body parts as the eyes and the brain. Because the implanted devices would not depend on battery power and would be activated only during short interrogation intervals and would otherwise be in the goff h state most of the time, the useful lifetimes of the implanted devices would be greater than those of comparable battery-powered implanted devices. The compactness of the hand-held transceiver units would facilitate transport and storage and would facilitate self-diagnosis by patients able to handle the units while away from medical facilities.
Aircraft interrogation and display system: A ground support equipment for digital flight systems
NASA Technical Reports Server (NTRS)
Glover, R. D.
1982-01-01
A microprocessor-based general purpose ground support equipment for electronic systems was developed. The hardware and software are designed to permit diverse applications in support of aircraft flight systems and simulation facilities. The implementation of the hardware, the structure of the software, describes the application of the system to an ongoing research aircraft project are described.
The role of abusive states of being in interrogation.
Putnam, Frank W
2013-01-01
Interrogation, the questioning of persons detained by police, military, or intelligence organizations, is designed to extract information that a subject may resist disclosing. Interrogation techniques are frequently predicated on inducing mental states of despair, dread, dependency, and debility that weaken an individual's resistance. Descriptions of techniques from 2 Central Intelligence Agency training manuals are illustrated by examples from interviews of and writings by Murat Kurnaz, who was held at Guantánamo Bay Detention Camp for 5 years. Interrogation techniques are designed to create a destabilizing sense of shock; undermine an individual's grasp on reality; and provoke internal psychological division, self-conflict, and confusion. The long-term effects of interrogation often include posttraumatic stress disorder as well as states of anxiety, depression, and depersonalization.
NASA Astrophysics Data System (ADS)
Ramshesh, Venkat K.; Knisley, Stephen B.
2006-03-01
Cardiac optical mapping currently provides 2-D maps of transmembrane voltage-sensitive fluorescence localized near the tissue surface. Methods for interrogation at different depths are required for studies of arrhythmias and the effects of defibrillation shocks in 3-D cardiac tissue. We model the effects of coloading with a dye that absorbs excitation or fluorescence light on the radius and depth of the interrogated region with specific illumination and collection techniques. Results indicate radii and depths of interrogation are larger for transillumination versus epi-illumination, an effect that is more pronounced for broad-field excitation versus laser scanner. Coloading with a fluorescence absorber lessens interrogated depth for epi-illumination and increases it for transillumination, which is confirmed with measurements using transillumination of heart tissue slices. Coloading with an absorber of excitation light consistently decreases the interrogated depths. Transillumination and coloading also decrease the intensities of collected fluorescence. Thus, localization can be modified with wavelength-specific absorbers at the expense of a reduction in fluorescence intensity.
Police practices and perceptions regarding juvenile interrogation and interrogative suggestibility.
Meyer, Jessica R; Reppucci, N Dickon
2007-01-01
Recent media coverage has highlighted cases in which young suspects were wrongly convicted because they provided interrogation-induced false confessions. Although youth may be more highly suggestible and easily influenced by authority than adults, police are trained to use the same psychologically coercive and deceptive tactics with youth as with adults. This investigation is the first standard documentation of the reported interrogation practices of law enforcement and police beliefs about the reliability of these techniques and their knowledge of child development. Participants were 332 law enforcement officers who completed surveys about interrogation procedures and developmental issues pertaining to youth. Results indicated that, while police acknowledge some developmental differences between youth and adults, there were indications that (1) how police perceive youth in general and how they perceive and treat them in the interrogation context may be contradictory and (2) their general view is that youth can be dealt with in the same manner as adults. Copyright (c) 2007 John Wiley & Sons, Ltd.
Magnetic Field Response Measurement Acquisition System
NASA Technical Reports Server (NTRS)
Woodard, Stanley E. (Inventor); Taylor, Bryant D. (Inventor); Shams, Qamar A. (Inventor); Fox, Robert L. (Inventor); Fox, Christopher L. (Inventor); Fox, Melanie L. (Inventor); Bryant, Robert G. (Inventor)
2006-01-01
Magnetic field response sensors designed as passive inductor-capacitor circuits produce magnetic field responses whose harmonic frequencies correspond to states of physical properties for which the sensors measure. Power to the sensing element is acquired using Faraday induction. A radio frequency antenna produces the time varying magnetic field used for powering the sensor, as well as receiving the magnetic field response of the sensor. An interrogation architecture for discerning changes in sensor s response kequency, resistance and amplitude is integral to the method thus enabling a variety of measurements. Multiple sensors can be interrogated using this method, thus eliminating the need to have a data acquisition channel dedicated to each sensor. The method does not require the sensors to be in proximity to any form of acquisition hardware. A vast array of sensors can be used as interchangeable parts in an overall sensing system.
Gudjonsson, Gisli H; Sigurdsson, Jon Fridrik; Sigfusdottir, Inga Dora; Asgeirsdottir, Bryndis Bjork; González, Rafael A; Young, Susan
2016-03-01
The principal aims of this study are to identify risk factors associated with police arrest and false confessions and to investigate whether the severity of the ADHD condition/symptoms increases the risk. 22,226 young persons in Iceland anonymously completed self-report questionnaires screening for conduct disorder and ADHD. In addition, they stated whether they had a diagnosis of ADHD and had received ADHD medication, and their history of offending, police interrogation and false confession. Participants were stratified into two age groups, 14-16 and 17-24 years. The older group was significantly more likely to have been interrogated by the police but the younger group were much more vulnerable to false confession during interrogation. Males were more likely to be at risk for both than females. The severity of the ADHD condition increased the risk of both interrogation and false confession. Negative binomial regressions showed that age, gender, conduct disorder, offending, and ADHD symptoms were all significant predictors of both interrogations and number of false confessions. Conduct disorder was the single best predictor of police interrogation, but the findings were more mixed regarding false confessions. Young people presenting with a combination of severe ADHD and comorbid conduct disorder had the worst outcome for both interrogation and false confessions. The findings endorse the need for support of persons with ADHD to be put in place to ensure fair due process and to prevent miscarriages of justice.
Covalent Ligand Discovery against Druggable Hotspots Targeted by Anti-cancer Natural Products.
Grossman, Elizabeth A; Ward, Carl C; Spradlin, Jessica N; Bateman, Leslie A; Huffman, Tucker R; Miyamoto, David K; Kleinman, Jordan I; Nomura, Daniel K
2017-11-16
Many natural products that show therapeutic activities are often difficult to synthesize or isolate and have unknown targets, hindering their development as drugs. Identifying druggable hotspots targeted by covalently acting anti-cancer natural products can enable pharmacological interrogation of these sites with more synthetically tractable compounds. Here, we used chemoproteomic platforms to discover that the anti-cancer natural product withaferin A targets C377 on the regulatory subunit PPP2R1A of the tumor-suppressor protein phosphatase 2A (PP2A) complex leading to activation of PP2A activity, inactivation of AKT, and impaired breast cancer cell proliferation. We developed a more synthetically tractable cysteine-reactive covalent ligand, JNS 1-40, that selectively targets C377 of PPP2R1A to impair breast cancer signaling, proliferation, and in vivo tumor growth. Our study highlights the utility of using chemoproteomics to map druggable hotspots targeted by complex natural products and subsequently interrogating these sites with more synthetically tractable covalent ligands for cancer therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.
ONeil, Colleen E; Jackson, Joshua M; Shim, Sang-Hee; Soper, Steven A
2016-04-05
We present a novel approach for characterizing surfaces utilizing super-resolution fluorescence microscopy with subdiffraction limit spatial resolution. Thermoplastic surfaces were activated by UV/O3 or O2 plasma treatment under various conditions to generate pendant surface-confined carboxylic acids (-COOH). These surface functional groups were then labeled with a photoswitchable dye and interrogated using single-molecule, localization-based, super-resolution fluorescence microscopy to elucidate the surface heterogeneity of these functional groups across the activated surface. Data indicated nonuniform distributions of these functional groups for both COC and PMMA thermoplastics with the degree of heterogeneity being dose dependent. In addition, COC demonstrated relative higher surface density of functional groups compared to PMMA for both UV/O3 and O2 plasma treatment. The spatial distribution of -COOH groups secured from super-resolution imaging were used to simulate nonuniform patterns of electroosmotic flow in thermoplastic nanochannels. Simulations were compared to single-particle tracking of fluorescent nanoparticles within thermoplastic nanoslits to demonstrate the effects of surface functional group heterogeneity on the electrokinetic transport process.
Using Elaborative Interrogation Enhanced Worked Examples to Improve Chemistry Problem Solving
ERIC Educational Resources Information Center
Pease, Rebecca Simpson
2012-01-01
Elaborative interrogation, which prompts students to answer why-questions placed strategically within informational text, has been shown to increase learning comprehension through reading. In this study, elaborative interrogation why-questions requested readers to explain why paraphrased statements taken from a reading were "true."…
University Sustainability Reporting: Taking Stock of Transparency
ERIC Educational Resources Information Center
Bice, Sara; Coates, Hamish
2016-01-01
This paper interrogates the case for improved and broadened public sustainability reporting by universities, and explores whether and how global performance measures capture the institutional attitudes and activities pertinent to universities' contributions to sustainability. The analysis explores all stand-alone, English language reports produced…
Bright Lights and Questions: Using Mutual Interrogation
ERIC Educational Resources Information Center
Adam, Aishikin; Alangui, Willy; Barton, Bill
2010-01-01
Mutual Interrogation is a research methodology for ethnomathematics proposed by Alangui in 2006 in an attempt to avoid the potential inequality set up when a restricted cultural practice is viewed through the lens of the near-universal and highly developed research domain of mathematics. Using three significant examples of mutual interrogation in…
Elaborative-Interrogation and Prior-Knowledge Effects on Learning of Facts.
ERIC Educational Resources Information Center
Woloshyn, Vera E.; And Others
1992-01-01
The differences among elaborative-interrogation, reading-to-understand, and no-exposure control conditions with familiar domain material in contrast to unfamiliar domain material were studied for 50 Canadian and 50 west German undergraduates. Results provide evidence of effects of both elaborative interrogation and prior knowledge on learning.…
Chelliah, Pandian; Sahoo, Trilochan; Singh, Sheela; Sujatha, Annie
2015-10-20
A Fourier transform spectrometer (FTS) used for interrogating a fiber Bragg grating (FBG) consists of a scanning-type interferometer. The FTS has a broad wavelength range of operation and good multiplexing capability. However, it has poor wavelength resolution and interrogation speed. We propose a modification to the FTS using path delay multiplexing to improve the same. Using this method, spatial resolution and interrogation time can be improved by n times by using n path delays. In this paper, simulation results for n=2, 5 are shown.
Low-cost interferometric TDM technology for dynamic sensing applications
NASA Astrophysics Data System (ADS)
Bush, Jeff; Cekorich, Allen
2004-12-01
A low-cost design approach for Time Division Multiplexed (TDM) fiber-optic interferometric interrogation of multi-channel sensor arrays is presented. This paper describes the evolutionary design process of the subject design. First, the requisite elements of interferometric interrogation are defined for a single channel sensor. The concept is then extended to multi-channel sensor interrogation implementing a TDM multiplex scheme where "traditional" design elements are utilized. The cost of the traditional TDM interrogator is investigated and concluded to be too high for entry into many markets. A new design approach is presented which significantly reduces the cost for TDM interrogation. This new approach, in accordance with the cost objectives, shows promise to bring this technology to within the threshold of commercial acceptance for a wide range of distributed fiber sensing applications.
DOT National Transportation Integrated Search
1971-06-01
An analysis has been made of the potentialities and problems involved in assigning some computer processing and control functions to the remote sites in an upgraded third generation air traffic control system. Interrogator sites offer the most fruitf...
Design challenges of a tunable laser interrogator for geo-stationary communication satellites
NASA Astrophysics Data System (ADS)
Ibrahim, Selwan K.; Honniball, Arthur; McCue, Raymond; Todd, Michael; O'Dowd, John A.; Sheils, David; Voudouris, Liberis; Farnan, Martin; Hurni, Andreas; Putzer, Philipp; Lemke, Norbert; Roner, Markus
2017-09-01
Recently optical sensing solutions based on fiber Bragg grating (FBG) technology have been proposed for temperature monitoring in telecommunication satellite platforms with an operational life time beyond 15 years in geo-stationary orbit. Developing radiation hardened optical interrogators designed to be used with FBG sensors inscribed in radiation tolerant fibers offer the capabilities of multiplexing multiple sensors on the same fiber and reducing the overall weight by removing the copper wiring harnesses associated with electrical sensors. Here we propose the use of a tunable laser based optical interrogator that uses a semiconductor MG-Y type laser that has no moving parts and sweeps across the C-band wavelength range providing optical power to FBG sensors and optical wavelength references such as athermal Etalons and Gas Cells to guarantee stable operation of the interrogator over its targeted life time in radiation exposed environments. The MG-Y laser was calibrated so it remains in a stable operation mode which ensures that no mode hops occur due to aging of the laser, and/or thermal or radiation effects. The key optical components including tunable laser, references and FBGs were tested for radiation tolerances by emulating the conditions on a geo-stationary satellite including a Total Ionizing Dose (TID) radiation level of up to 100 krad for interrogator components and 25 Mrad for FBGs. Different tunable laser control, and signal processing algorithms have been designed and developed to fit within specific available radiation hardened FPGAs to guarantee operation of a single interrogator module providing at least 1 sample per second measurement capability across <20 sensors connected to two separate optical channels. In order to achieve the required temperature specifications of +/-0.5°C across a temperature range of -20°C to +65°C using femtosecond inscribed FBGs (fs-FBG), a polarization switch is used to mitigate for the polarization dependent frequency shift (PDFS) induced from fs-FBG which could be in the order of < 20 pm causing < 2°C error in the measurement. Also special transducers were designed to isolate the strain from the FBGs to reduce any strain influence on the FBG temperature measurements while ensuring high thermal conductivity. In this paper we demonstrate the operation of an optical FBG interrogator as part of a hybrid sensor bus (HSB) engineering model system developed in the frame of an ESA-ARTES program and is planned to be deployed as a flight demonstrator on-board the German Heinrich Hertz geo-stationary satellite.
Mayer, Michael F.; Nattress, J.; Jovanovic, I.
2016-06-27
Detection of unique signatures of special nuclear materials is critical for their interdiction in a variety of nuclear security and nonproliferation scenarios. We report on the observation of delayed neutrons from fission of uranium induced in dual-particle active interrogation based on the 11B(d,n γ) 12C nuclear reaction. Majority of the fissions are attributed to fast fission induced by the incident quasi-monoenergetic neutrons. A Li-doped glass–polymer composite scintillation neutron detector, which displays excellent neutron/γ discrimination at low energies, was used in the measurements, along with a recoil-based liquid scintillation detector. Time- dependent buildup and decay of delayed neutron emission from 238Umore » were measured between the interrogating beam pulses and after the interrogating beam was turned off, respectively. Characteristic buildup and decay time profiles were compared to the common parametrization into six delayed neutron groups, finding a good agreement between the measurement and nuclear data. Furthermore, this method is promising for detecting fissile and fissionable materials in cargo scanning applications and can be readily integrated with transmission radiography using low-energy nuclear reaction sources.« less
Active Well Counting Using New PSD Plastic Detectors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hausladen, Paul; Newby, Jason; McElroy, Robert Dennis
This report presents results and analysis from a series of proof-of-concept measurements to assess the suitability of segmented detectors constructed from Eljen EJ-299-34 PSD-plastic scintillator with pulse-shape discrimination capability for the purposes of quantifying uranium via active neutron coincidence counting. Present quantification of bulk uranium materials for international safeguards and domestic materials control and accounting relies on active neutron coincidence counting systems, such as the Active Well Coincidence Counter (AWCC) and the Uranium Neutron Coincidence Collar (UNCL), that use moderated He-3 proportional counters along with necessarily low-intensity 241Am(Li) neutron sources. Scintillation-based fast-neutron detectors are a potentially superior technology to themore » existing AWCC and UNCL designs due to their spectroscopic capability and their inherently short neutron coincidence times that largely eliminate random coincidences and enable interrogation by stronger sources. One of the past impediments to the investigation and adoption of scintillation counters for the purpose of quantifying bulk uranium was the commercial availability of scintillators having the necessary neutron-gamma pulse-shape discrimination properties only as flammable liquids. Recently, Eljen EJ-299-34 PSD-plastic scintillator became commercially available. The present work is the first assessment of an array of PSD-plastic detectors for the purposes of quantifying bulk uranium. The detector panel used in the present work was originally built as the focal plane for a fast-neutron imager, but it was repurposed for the present investigation by construction of a stand to support the inner well of an AWCC immediately in front of the detector panel. The detector panel and data acquisition of this system are particularly well suited for performing active-well fast-neutron counting of LEU and HEU samples because the active detector volume is solid, the 241Am(Li) interrogating neutrons are largely below the detector threshold, and the segmented construction of the detector modules allow for separation of true neutron-neutron coincidences from inter-detector scattering using the kinematics of neutron scattering. The results from a series of measurements of a suite of uranium standards are presented, and compared to measurements of the same standards and source configurations using the AWCC. Using these results, the performance of the segmented detectors reconfigured as a well counter is predicted and outperforms the AWCC.« less
Inferring rules of lineage commitment in haematopoiesis.
Pina, Cristina; Fugazza, Cristina; Tipping, Alex J; Brown, John; Soneji, Shamit; Teles, Jose; Peterson, Carsten; Enver, Tariq
2012-02-19
How the molecular programs of differentiated cells develop as cells transit from multipotency through lineage commitment remains unexplored. This reflects the inability to access cells undergoing commitment or located in the immediate vicinity of commitment boundaries. It remains unclear whether commitment constitutes a gradual process, or else represents a discrete transition. Analyses of in vitro self-renewing multipotent systems have revealed cellular heterogeneity with individual cells transiently exhibiting distinct biases for lineage commitment. Such systems can be used to molecularly interrogate early stages of lineage affiliation and infer rules of lineage commitment. In haematopoiesis, population-based studies have indicated that lineage choice is governed by global transcriptional noise, with self-renewing multipotent cells reversibly activating transcriptome-wide lineage-affiliated programs. We examine this hypothesis through functional and molecular analysis of individual blood cells captured from self-renewal cultures, during cytokine-driven differentiation and from primary stem and progenitor bone marrow compartments. We show dissociation between self-renewal potential and transcriptome-wide activation of lineage programs, and instead suggest that multipotent cells experience independent activation of individual regulators resulting in a low probability of transition to the committed state.
ERIC Educational Resources Information Center
Sumsion, Jennifer; Wong, Sandie
2011-01-01
In this article, the authors interrogate the use of "belonging" in "Belonging, Being and Becoming: the Early Years Learning Framework for Australia" (EYLF), Australia's first national curriculum for early childhood education and care settings and, from the authors' interrogation, possibilities are offered for thinking about and…
CLINICAL AUTONOMIC NEUROPHYSIOLOGY AND THE MALE SEXUAL RESPONSE: AN OVERVIEW
Yang, Claire C.; Jiang, Xiaogang
2009-01-01
Introduction Clinical neurophysiology is the study of the human nervous system through the recording of bioelectrical activity. In the realm of male sexual functioning, this includes using electrophysiologic techniques to study the nerves subserving erection, emission, ejaculation, and orgasm. Aim To introduce the reader to the principles of clinical neurophysiology as they relate to the male sexual response, particularly erection. Methods We review the pertinent autonomic neuroanatomy and neurophysiology of reflexes relevant to the male sexual response, as well as summarize the genital electrodiagnostic tests that are being used to interrogate the autonomic innervation pertinent to male sexual functioning. Conclusions The male sexual response is a coordinated series of interactions between the somatic and the autonomic nervous systems. Measurement of the autonomically mediated portions of the sexual reflexes is of great clinical interest, particularly in relation to erection. Advances in clinical electrodiagnostics now allow for consistent recording of evoked and spontaneous intra-penile electrical activity. However, before broad and widespread use of these techniques is possible, more investigations are needed. PMID:19267845
Repetitive Interrogation of 2-Level Quantum Systems
NASA Technical Reports Server (NTRS)
Prestage, John D.; Chung, Sang K.
2010-01-01
Trapped ion clocks derive information from a reference atomic transition by repetitive interrogations of the same quantum system, either a single ion or ionized gas of many millions of ions. Atomic beam frequency standards, by contrast, measure reference atomic transitions in a continuously replenished "flow through" configuration where initial ensemble atomic coherence is zero. We will describe some issues and problems that can arise when atomic state selection and preparation of the quantum atomic system is not completed, that is, optical pumping has not fully relaxed the coherence and also not fully transferred atoms to the initial state. We present a simple two-level density matrix analysis showing how frequency shifts during the state-selection process can cause frequency shifts of the measured clock transition. Such considerations are very important when a low intensity lamp light source is used for state selection, where there is relatively weak relaxation and re-pumping of ions to an initial state and much weaker 'environmental' relaxation of the atomic coherence set-up in the atomic sample.
InGaAs multiple quantum well modulating retro-reflector for free-space optical communications
NASA Astrophysics Data System (ADS)
Rabinovich, William S.; Gilbreath, G. Charmaine; Goetz, Peter G.; Mahon, Rita; Katzer, D. Scott; Ikossi-Anastasiou, Kiki; Binari, Steven C.; Meehan, Timothy J.; Stell, Mena F.; Sokolsky, Ilene; Vasquez, John A.; Vilcheck, Michael J.
2002-01-01
Modulating retro-reflectors provide means for free space optical communication without the need for a laser, telescope or pointer tracker on one end of the link. These systems work by coupling a retro-reflector with an electro- optic shutter. The modulating retro-reflector is then interrogated by a cw laser beam from a conventional optical communications system and returns a modulated signal beam to the interrogator. Over the last few years the Naval Research Laboratory has developed modulating retro-reflector based on corner cubes and large area Transmissive InGaAs multiple quantum well modulators. These devices can allow optical links at speeds up to about 10 Mbps. We will discuss the critical performance characteristics of such systems including modulating rate, power consumption, optical contrast ratio and operating wavelength. In addition a new modulating retro-reflector architecture based upon cat s eye retroreflectors will be discussed. This architecture has the possibility for data rates of hundreds of megabits per second at power consumptions below 100 mW.
Additively Manufactured IN718 Components with Wirelessly Powered and Interrogated Embedded Sensing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Attridge, Paul; Bajekal, Sanjay; Klecka, Michael
A methodology is described for embedding commercial-off-the-shelf sensors together with wireless communication and power circuit elements using direct laser metal sintered additively manufactured components. Physics based models of the additive manufacturing processes and sensor/wireless level performance models guided the design and embedment processes. A combination of cold spray deposition and laser engineered net shaping was used to fashion the transmitter/receiving elements and embed the sensors, thereby providing environmental protection and component robustness/survivability for harsh conditions. By design, this complement of analog and digital sensors were wirelessly powered and interrogated using a health and utilization monitoring system; enabling real-time, in situmore » prognostics and diagnostics.« less
The Operating Room of the Future Versus the Future of the Operating Room.
Kassam, Amin B; Rovin, Richard A; Walia, Sarika; Chakravarthi, Srikant; Celix, Juanita; Jennings, Jonathan; Khalili, Sammy; Gonen, Lior; Monroy-Sosa, Alejandro; Fukui, Melanie B
2017-06-01
Technological advancement in the operating room is evolving into a dynamic system mirroring that of the aeronautics industry. Through data visualization, information is continuously being captured, collected, and stored on a scalable informatics platform for rapid, intuitive, iterative learning. The authors believe this philosophy (paradigm) will feed into an intelligent informatics domain fully accessible to all and geared toward precision, cell-based therapy in which tissue can be targeted and interrogated in situ. In the future, the operating room will be a venue that facilitates this real-time tissue interrogation, which will guide in situ therapeutics to restore the state of health. Copyright © 2017 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clayton, James; Shedlock, Daniel; Langeveld, Willem G.J.
In the security and inspection market, there is a push towards highly mobile, reduced-dose active interrogation scanning and imaging systems to allow operation in urban environments. To achieve these goals, the accelerator system design needs to be smaller than existing systems. A smaller radiation exclusion zone may be accomplished through better beam collimation and an integrated, x-ray-source/detector-array assembly to allow feedback and control of an intensity-modulated x-ray source. A shaped low-Z target in the x-ray source can be used to generate a more forward peaked x-ray beam. Electron-beam steering can then be applied to direct the forward-peaked x rays towardmore » areas in the cargo with high attenuation. This paper presents an exploratory study to identify components and upgrades that would be required to meet the desired specifications, as well as the best technical approach to design and build a prototype.« less
NASA Technical Reports Server (NTRS)
Hammond, Dana P.
1991-01-01
The Technical Requirements Analysis and Control Systems (TRACS) software package is described. TRACS offers supplemental tools for the analysis, control, and interchange of project requirements. This package provides the fundamental capability to analyze and control requirements, serves a focal point for project requirements, and integrates a system that supports efficient and consistent operations. TRACS uses relational data base technology (ORACLE) in a stand alone or in a distributed environment that can be used to coordinate the activities required to support a project through its entire life cycle. TRACS uses a set of keyword and mouse driven screens (HyperCard) which imposes adherence through a controlled user interface. The user interface provides an interactive capability to interrogate the data base and to display or print project requirement information. TRACS has a limited report capability, but can be extended with PostScript conventions.
Gelatin device for the delivery of growth factors involved in endochondral ossification.
Ahrens, Lucas A J; Vonwil, Daniel; Christensen, Jon; Shastri, V Prasad
2017-01-01
Controlled release drug delivery systems are well established as oral and implantable dosage forms. However, the controlled release paradigm can also be used to present complex soluble signals responsible for cellular organization during development. Endochondral ossification (EO), the developmental process of bone formation from a cartilage matrix is controlled by several soluble signals with distinct functions that vary in structure, molecular weight and stability. This makes delivering them from a single vehicle rather challenging. Herein, a gelatin-based delivery system suitable for the delivery of small molecules as well as recombinant human (rh) proteins (rhWNT3A, rhFGF2, rhVEGF, rhBMP4) is reported. The release behavior and biological activity of the released molecules was validated using analytical and biological assays, including cell reporter systems. The simplicity of fabrication of the gelatin device should foster its adaptation by the diverse scientific community interested in interrogating developmental processes, in vivo.
Gelatin device for the delivery of growth factors involved in endochondral ossification
Ahrens, Lucas A. J.; Vonwil, Daniel; Christensen, Jon
2017-01-01
Controlled release drug delivery systems are well established as oral and implantable dosage forms. However, the controlled release paradigm can also be used to present complex soluble signals responsible for cellular organization during development. Endochondral ossification (EO), the developmental process of bone formation from a cartilage matrix is controlled by several soluble signals with distinct functions that vary in structure, molecular weight and stability. This makes delivering them from a single vehicle rather challenging. Herein, a gelatin-based delivery system suitable for the delivery of small molecules as well as recombinant human (rh) proteins (rhWNT3A, rhFGF2, rhVEGF, rhBMP4) is reported. The release behavior and biological activity of the released molecules was validated using analytical and biological assays, including cell reporter systems. The simplicity of fabrication of the gelatin device should foster its adaptation by the diverse scientific community interested in interrogating developmental processes, in vivo. PMID:28380024
Chemical and Biophysical Modulation of Cas9 for Tunable Genome Engineering.
Nuñez, James K; Harrington, Lucas B; Doudna, Jennifer A
2016-03-18
The application of the CRISPR-Cas9 system for genome engineering has revolutionized the ability to interrogate genomes of mammalian cells. Programming the Cas9 endonuclease to induce DNA breaks at specified sites is achieved by simply modifying the sequence of its cognate guide RNA. Although Cas9-mediated genome editing has been shown to be highly specific, cleavage events at off-target sites have also been reported. Minimizing, and eventually abolishing, unwanted off-target cleavage remains a major goal of the CRISPR-Cas9 technology before its implementation for therapeutic use. Recent efforts have turned to chemical biology and biophysical approaches to engineer inducible genome editing systems for controlling Cas9 activity at the transcriptional and protein levels. Here, we review recent advancements to modulate Cas9-mediated genome editing by engineering split-Cas9 constructs, inteins, small molecules, protein-based dimerizing domains, and light-inducible systems.
Active interrogation of highly enriched uranium
NASA Astrophysics Data System (ADS)
Fairrow, Nannette Lea
Safeguarding special nuclear material (SNM) in the Department of Energy Complex is vital to the national security of the United States. Active and passive nondestructive assays are used to confirm the presence of SNM in various configurations ranging from waste to nuclear weapons. Confirmation measurements for nuclear weapons are more challenging because the design complicates the detection of a distinct signal for highly enriched uranium. The emphasis of this dissertation was to investigate a new nondestructive assay technique that provides an independent and distinct signal to confirm the presence of highly enriched uranium (HEU). Once completed and tested this assay method could be applied to confirmation measurements of nuclear weapons. The new system uses a 14-MeV neutron source for interrogation and records the arrival time of neutrons between the pulses with a high efficiency detection system. The data is then analyzed by the Feynman reduced variance method. The analysis determined the amount of correlation in the data and provided a unique signature of correlated fission neutrons. Measurements of HEU spheres were conducted at Los Alamos with the new system. Then, Monte Carlo calculations were performed to verify hypothesis made about the behavior of the neutrons in the experiment. Comparisons of calculated counting rates by the Monte Carlo N-Particle Transport Code (MCNP) were made with the experimental data to confirm that the measured response reflected the desired behavior of neutron interactions in the highly enriched uranium. In addition, MCNP calculations of the delayed neutron build-up were compared with the measured data. Based on the results obtained from this dissertation, this measurement method has the potential to be expanded to include mass determinations of highly enriched uranium. Although many safeguards techniques exist for measuring special nuclear material, the number of assays that can be used to confirm HEU in shielded systems is limited. These assays also rely on secondary characteristics of the material to be measured. A review of the nondestructive techniques with potential applications for nuclear weapons confirmatory measurements were evaluated with summaries of the pros and cons involved in implementing the methods at production type facilities.
Kao, Chung-Shan; Dietrich, Rainer; Sommer, Werner
2010-01-01
Background Languages differ in the marking of the sentence mood of a polar interrogative (yes/no question). For instance, the interrogative mood is marked at the beginning of the surface structure in Polish, whereas the marker appears at the end in Chinese. In order to generate the corresponding sentence frame, the syntactic specification of the interrogative mood is early in Polish and late in Chinese. In this respect, German belongs to an interesting intermediate class. The yes/no question is expressed by a shift of the finite verb from its final position in the underlying structure into the utterance initial position, a move affecting, hence, both the sentence's final and the sentence's initial constituents. The present study aimed to investigate whether during generation of the semantic structure of a polar interrogative, i.e., the processing preceding the grammatical formulation, the interrogative mood is encoded according to its position in the syntactic structure at distinctive time points in Chinese, German, and Polish. Methodology/Principal Findings In a two-choice go/nogo experimental design, native speakers of the three languages responded to pictures by pressing buttons and producing utterances in their native language while their brain potentials were recorded. The emergence and latency of lateralized readiness potentials (LRP) in nogo conditions, in which speakers asked a yes/no question, should indicate the time point of processing the interrogative mood. The results revealed that Chinese, German, and Polish native speakers did not differ from each other in the electrophysiological indicator. Conclusions/Significance The findings suggest that the semantic encoding of the interrogative mood is temporally consistent across languages despite its disparate syntactic specification. The consistent encoding may be ascribed to economic processing of interrogative moods at various sentential positions of the syntactic structures in languages or, more generally, to the overarching status of sentence mood in the semantic structure. PMID:20927373
Effect of TCAS Interrogations on the Chicago O'Hare ATCRBS System
DOT National Transportation Integrated Search
1992-11-01
This report documents the Federal Aviation Administration (FAA) data collection : and analysis effort to investigate Secondary Surveillance Radar (SSR) problems : encountered at the Chicago O'Hare Terminal Approach Control (TRACON) facility. : The FA...
Clare, I C; Gudjonsson, G H
1993-09-01
In order to assess a criminal suspect's ability to make a reliable statement, performance on three measures--interrogative suggestibility, confabulation and acquiescence--may be used. This paper presents preliminary data on these measures for people with mild learning disabilities (Full Scale IQ [FSIQ]: 57-75). It was found that they were more suggestible than their average ability counterparts (FSIQ: 83-111) because they were much more susceptible to 'leading questions'. They also confabulated more and were more acquiescent. Overall, the data emphasized their potential vulnerability to giving erroneous testimony during interrogations.
Performance Optimization Design for a High-Speed Weak FBG Interrogation System Based on DFB Laser.
Yao, Yiqiang; Li, Zhengying; Wang, Yiming; Liu, Siqi; Dai, Yutang; Gong, Jianmin; Wang, Lixin
2017-06-22
A performance optimization design for a high-speed fiber Bragg grating (FBG) interrogation system based on a high-speed distributed feedback (DFB) swept laser is proposed. A time-division-multiplexing sensor network with identical weak FBGs is constituted to realize high-capacity sensing. In order to further improve the multiplexing capacity, a waveform repairing algorithm is designed to extend the dynamic demodulation range of FBG sensors. It is based on the fact that the spectrum of an FBG keeps stable over a long period of time. Compared with the pre-collected spectra, the distorted spectra waveform are identified and repaired. Experimental results show that all the identical weak FBGs are distinguished and demodulated at the speed of 100 kHz with a linearity of above 0.99, and the range of dynamic demodulation is extended by 40%.
Magnetic Field Response Measurement Acquisition System
NASA Technical Reports Server (NTRS)
Woodward, Stanley E. (Inventor); Taylor, Bryant D. (Inventor)
2007-01-01
Magnetic field response sensors designed as passive inductor- capacit or circuits produce magnetic field responses whose harmonic frequenci es correspond to states of physical properties for which the sensors measure. Power to the sensing element is acquired using Faraday induc tion. A radio frequency antenna produces the time varying magnetic fi eld used for powering the sensor, as well as receiving the magnetic field response of the sensor. An interrogation architecture for disce rning changes in sensor's response frequency, resistance and amplitud e is integral to the method thus enabling a variety of measurements. Multiple sensors can be interrogated using this method, thus eliminat ing the need to have a data acquisition channel dedicated to each se nsor. The method does not require the sensors to be in proximity to a ny form of acquisition hardware. A vast array of sensors can be used as interchangeable parts in an overall sensing system.
Performance Optimization Design for a High-Speed Weak FBG Interrogation System Based on DFB Laser
Yao, Yiqiang; Li, Zhengying; Wang, Yiming; Liu, Siqi; Dai, Yutang; Gong, Jianmin; Wang, Lixin
2017-01-01
A performance optimization design for a high-speed fiber Bragg grating (FBG) interrogation system based on a high-speed distributed feedback (DFB) swept laser is proposed. A time-division-multiplexing sensor network with identical weak FBGs is constituted to realize high-capacity sensing. In order to further improve the multiplexing capacity, a waveform repairing algorithm is designed to extend the dynamic demodulation range of FBG sensors. It is based on the fact that the spectrum of an FBG keeps stable over a long period of time. Compared with the pre-collected spectra, the distorted spectra waveform are identified and repaired. Experimental results show that all the identical weak FBGs are distinguished and demodulated at the speed of 100 kHz with a linearity of above 0.99, and the range of dynamic demodulation is extended by 40%. PMID:28640187
Optogenetic Induction of Aversive Taste Memory
C. Keene, Alex; Masek, Pavel
2013-01-01
The Drosophila melanogaster gustatory system consists of several neuronal pathways representing diverse taste modalities. The two predominant modalities are a sweet sensing pathway that mediates attraction, and a bitter sensing pathway that mediates avoidance. A central question is how flies integrate stimuli from these pathways and generate the appropriate behavioral response. We have developed a novel assay for induction of taste memories. We demonstrate that the gustatory response to fructose is suppressed when followed by the presence of bitter quinine. We employ optogenetic neural activation using infrared laser in combination with heat sensitive channel - TRPA1 to precisely activate gustatory neurons. This optogenetic system allows for spatially and temporally controlled activation of distinct neural classes in the gustatory circuit. We directly activated bitter-sensing neurons together with presentation of fructose for remote induction of aversive taste memories. Here we report that activation of bitter-sensing neurons in the proboscis suffices as a conditioning stimulus. Spatially restricted stimulation indicates that the conditioning stimulus is indeed a signal from the bitter neurons in the proboscis and it is independent of postingestive feedback. The coincidence of temporally specific activation of bitter-sensing neurons with fructose presentation is crucial for memory formation, establishing aversive taste learning in Drosophila as associative learning. Taken together, this optogenetic system provides a powerful new tool for interrogation of the central brain circuits that mediate memory formation. PMID:22820051
A multi-parameter optical fiber sensor with interrogation and discrimination capabilities
NASA Astrophysics Data System (ADS)
Zhan, Yage; Wu, Hua; Yang, Qinyu; Pei, Jincheng; Yang, Xichun
2009-11-01
A multi-parameter and multi-function, but low-cost, optical fiber grating sensor with self-interrogation and self-discrimination capabilities is presented theoretically and experimentally. The sensor bases on three fiber Bragg gratings (FBG) and one fiber long period grating (LPG). Strain, vibration, pressure, ordinary temperature (-10 to 100 °C) and high temperature (100-800 °C) can be measured by the sensor. When high temperature (100-800 °C) is measured, the LPG is used as a high temperture sensor head and FBG 1 is used as an interrogation element. Alternatively, when one of the other four measurands is measured, FBG 1 (or FBG 2) is used as a sensor head and LPG is used as an interrogation element. When two of the other four measurands are measured simultaneously, FBG 1 and FBG 2 are used as sensor heads and LPG is used as a shared interrogation element. FBG 3 is used as a reference element to eliminate the errors resulted from light source fluctuation and the cross-sensitivity between measurand and environmental temperature. The measurands can be interrogated according to the signals of the photodiodes (PDs), which are related to the relative wavelength shift of the LPG and the FBGs. Experimental results agree well with theoretical analyses. The interrogation scheme is immune to light source fluctuation and the cross-sensitivity between measurands and enviromental temperature, and also the dynamic range is large.
Handbook for Military Justice and Civil Law
2000-09-01
In most cases, however, to an individual to identify himself is not an "interrogation," and production of the identification is not a "statement...mind, the most productive approach for the reader is to develop a thorough knowledge of what actions are legally permissible (producing admissible...activities that constitute reasonable searches, and other command activities which, although permissible and productive of admissible evidence, are not
RFID Transponders' Radio Frequency Emissions in Aircraft Communication and Navigation Radio Bands
NASA Technical Reports Server (NTRS)
Nguyen, Truong X.; Ely, Jay J.; Williams, Reuben A.; Koppen, Sandra V.; Salud, Maria Theresa P.
2006-01-01
Radiated emissions in aircraft communication and navigation bands are measured from several active radio frequency identification (RFID) tags. The individual tags are different in design and operations. They may also operate in different frequency bands. The process for measuring the emissions is discussed, and includes tag interrogation, reverberation chamber testing, and instrument settings selection. The measurement results are described and compared against aircraft emission limits. In addition, interference path loss for the cargo bays of passenger aircraft is measured. Cargo bay path loss is more appropriate for RFID tags than passenger cabin path loss. The path loss data are reported for several aircraft radio systems on a Boeing 747 and an Airbus A320.
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...
ERIC Educational Resources Information Center
Asquith, Christina
2006-01-01
When reporters from the Arabic news channel Aljazeera International traveled on assignment to Crosby, North Dakota, they did not receive a warm welcome from locals. Instead, someone called the sheriff, who then reported possible terrorist activity to the U.S. Border Patrol. After a brief interrogation, agents confirmed that they were American…
Fiscal Year (FY) 2017 Activities for the Spent Fuel Nondestructive Assay Project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Trellue, Holly Renee; Trahan, Alexis Chanel; McMath, Garrett Earl
The main focus of research in the NA-241 spent fuel nondestructive assay (NDA) project in FY17 has been completing the fabrication and testing of two prototype instruments for upcoming spent fuel measurements at the Clab interim storage facility in Sweden. One is a passive instrument: Differential Die-away Self Interrogation-Passive Neutron Albedo Reactivity (DDSI), and one is an active instrument: Differential Die-Away-Californium Interrogation with Prompt Neutron (DDA). DDSI was fabricated and tested with fresh fuel at Los Alamos National Laboratory in FY15 and FY16, then shipped to Sweden at the beginning of FY17. Research was performed in FY17 to simplify resultsmore » from the data acquisition system, which is complex because signals from 56 different 3He detectors must be processed using list mode data. The DDA instrument was fabricated at the end of FY16. New high count rate electronics better suited for a spent fuel environment (i.e., KM-200 preamplifiers) were built specifically for this instrument in FY17, and new Tygon tubing to house electrical cables was purchased and installed. Fresh fuel tests using the DDA instrument with numerous configurations of fuel rods containing depleted uranium (DU), low enriched uranium (LEU), and LEU with burnable poisons (Gd) were successfully performed and compared to simulations.1 Additionally, members of the spent fuel NDA project team travelled to Sweden for a “spent fuel characterization and decay heat” workshop involving simulations of spent fuel and analysis of uncertainties in decay heat calculations.« less
ERIC Educational Resources Information Center
Geffen, Susan; Mintz, Toben H.
2015-01-01
Word order is a core mechanism for conveying syntactic structure, yet interrogatives usually disrupt canonical word orders. For example, in English, polar interrogatives typically invert the subject and auxiliary verb and insert an utterance-initial "do" if no auxiliary is present. These word order patterns result from differences in the…
ERIC Educational Resources Information Center
Woloshyn, Vera E.; And Others
1994-01-01
Thirty-two factual statements, half consistent and half not consistent with subjects' prior knowledge, were processed by 140 sixth and seventh graders. Half were directed to use elaborative interrogation (using prior knowledge) to answer why each statement was true. Across all memory measures, elaborative interrogation subjects performed better…
The Development of Interrogative Forms and Functions in Early Childhood Cantonese
ERIC Educational Resources Information Center
Li, Hui; Tse, Shek Kam; Sin Wong, Jessie Ming; Mei Wong, Eileen Chin; Leung, Shing On
2013-01-01
This study investigated question acquisition in Cantonese-speaking young children with a focus on the development of interrogative forms and functions. Data from a child Cantonese corpus (492 children aged 36, 48 and 60 months) were analysed. The main results were that: (1) all the interrogative forms and functions were produced by the three age…
Teacher Quality, Appraisal and Development: The Flaws in the IQMS
ERIC Educational Resources Information Center
De Clerq, Francine
2008-01-01
This article addresses the issue of how to monitor and develop the quality of teaching in schools by identifying the international lessons of teacher appraisal, monitoring and support systems and by interrogating the recently introduced South African Integrated Quality Management System (IQMS). The aim is to show why teacher monitoring and…
Slaughter, Dennis R.; Pohl, Bertram A.; Dougan, Arden D.; Bernstein, Adam; Prussin, Stanley G.; Norman, Eric B.
2008-04-15
A system for inspecting cargo for the presence of special nuclear material. The cargo is irradiated with neutrons. The neutrons produce fission products in the special nuclear material which generate gamma rays. The gamma rays are detecting indicating the presence of the special nuclear material.
Composite-cavity-based Fabry-Perot interferometric strain sensors.
Zhang, Jianzhong; Peng, G D; Yuan, Libo; Sun, Weimin
2007-07-01
A composite-cavity-based Fabry-Perot interferometric strain sensor system is proposed to gain the minimum cross sensitivity to temperature and a high multiplexing capability at the same time. The interrogation of the sensor system is based on a white-light interferometric technology, and the demodulation is achieved by analyzing the coherence spectra. A demonstration system with two sensors is presented and tested.
Shvets, Alexey A; Kolomeisky, Anatoly B
2017-10-03
The ability to precisely edit and modify a genome opens endless opportunities to investigate fundamental properties of living systems as well as to advance various medical techniques and bioengineering applications. This possibility is now close to reality due to a recent discovery of the adaptive bacterial immune system, which is based on clustered regularly interspaced short palindromic repeats (CRISPR)-associated proteins (Cas) that utilize RNA to find and cut the double-stranded DNA molecules at specific locations. Here we develop a quantitative theoretical approach to analyze the mechanism of target search on DNA by CRISPR RNA-guided Cas9 proteins, which is followed by a selective cleavage of nucleic acids. It is based on a discrete-state stochastic model that takes into account the most relevant physical-chemical processes in the system. Using a method of first-passage processes, a full dynamic description of the target search is presented. It is found that the location of specific sites on DNA by CRISPR Cas9 proteins is governed by binding first to protospacer adjacent motif sequences on DNA, which is followed by reversible transitions into DNA interrogation states. In addition, the search dynamics is strongly influenced by the off-target cutting. Our theoretical calculations allow us to explain the experimental observations and to give experimentally testable predictions. Thus, the presented theoretical model clarifies some molecular aspects of the genome interrogation by CRISPR RNA-guided Cas9 proteins. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Huang, Shieh-Kung; Loh, Kenneth J.
2015-04-01
The main goal of this study was to develop and validate the performance of a miniature and portable data acquisition (DAQ) system designed for interrogating carbon nanotube (CNT)-based thin films for real-time spatial structural sensing and damage detection. Previous research demonstrated that the electrical properties of CNT-based thin film strain sensors were linearly correlated with applied strains. When coupled with an electrical impedance tomography (EIT) algorithm, the detection and localization of damage was possible. In short, EIT required that the film or "sensing skin" be interrogated along its boundaries. Electrical current was injected across a pair of boundary electrodes, and voltage was simultaneously recorded along the remaining electrode pairs. This was performed multiple times to obtain a large dataset needed for solving the EIT spatial conductivity mapping inverse problem. However, one of the main limitations of this technique was the large amount of time required for data acquisition. In order to facilitate the adoption of this technology and for field implementation purposes, a miniature DAQ that could interrogate these CNT-based sensing skins at high sampling rates was designed and tested. The prototype DAQ featured a Howland current source that could generate stable and controlled direct current. Measurement of boundary electrode voltages and the switching of the input, output, and measurement channels were achieved using multiplexer units. The DAQ prototype was fabricated on a two-layer printed circuit board, and it was designed for integration with a prototype wireless sensing system, which is the next phase of this research.
Event-recording devices with identification codes
NASA Technical Reports Server (NTRS)
Watters, David G. (Inventor); Huestis, David L. (Inventor); Bahr, Alfred J. (Inventor); Vidmar, Robert J. (Inventor)
2003-01-01
A recording device allows wireless interrogation to determine its identity and its state. The state indicates whether one or more physical or chemical events have taken place. In effect, the one or more physical or chemical events are recorded by the device. The identity of the device allows it to be distinguished from a number of similar devices. The recording device may be used in an array of devices that allows wireless probing by an interrogation unit. When probed, each device tells the interrogator who it is and what state it is in. The devices allow multiple use and the interrogator may use a logical reset to determine the state of each device. The interrogator can thus easily identify particular items in an array that have reached a particular condition. The device may record the status of each device in a database to maintain a history for each.
Frequency steerable acoustic transducers
NASA Astrophysics Data System (ADS)
Senesi, Matteo
Structural health monitoring (SHM) is an active research area devoted to the assessment of the structural integrity of critical components of aerospace, civil and mechanical systems. Guided wave methods have been proposed for SHM of plate-like structures using permanently attached piezoelectric transducers, which generate and sense waves to evaluate the presence of damage. Effective interrogation of structural health is often facilitated by sensors and actuators with the ability to perform electronic, i.e. phased array, scanning. The objective of this research is to design an innovative directional piezoelectric transducer to be employed for the localization of broadband acoustic events, or for the generation of Lamb waves for active interrogation of structural health. The proposed Frequency Steerable Acoustic Transducers (FSATs) are characterized by a spatial arrangement of active material which leads to directional characteristics varying with frequency. Thus FSATs can be employed both for directional sensing and generation of guided waves without relying on phasing and control of a large number of channels. The analytical expression of the shape of the FSATs is obtained through a theoretical formulation for continuously distributed active material as part of a shaped piezoelectric device. The FSAT configurations analyzed in this work are a quadrilateral array and a geometry which corresponds to a spiral in the wavenumber domain. The quadrilateral array is experimentally validated, confirming the concept of frequency-dependent directionality. Its limited directivity is improved by the Wavenumber Spiral FSAT (WS-FSAT), which, instead, is characterized by a continuous frequency dependent directionality. Preliminary validations of the WS-FSAT, using a laser doppler vibrometer, are followed by the implementation of the WS-FSAT as a properly shaped piezo transducer. The prototype is first used for localization of acoustic broadband sources. Signal processing algorithms and related imaging techniques for damage location are also presented. Finally, the WS-FSAT has also been experimentally validated in generation.
Wearable Wireless Telemetry System for Implantable BioMEMS Sensors
NASA Technical Reports Server (NTRS)
Simons, Rainee N.; Miranda, Felix A.; Wilson, Jeffrey D.; Simons, Renita E.
2008-01-01
Telemetry systems of a type that have been proposed for the monitoring of physiological functions in humans would include the following subsystems: Surgically implanted or ingested units that would comprise combinations of microelectromechanical systems (MEMS)- based sensors [bioMEMS sensors] and passive radio-frequency (RF) readout circuits that would include miniature loop antennas. Compact radio transceiver units integrated into external garments for wirelessly powering and interrogating the implanted or ingested units. The basic principles of operation of these systems are the same as those of the bioMEMS-sensor-unit/external-RFpowering- and-interrogating-unit systems described in "Printed Multi-Turn Loop Antennas for Biotelemetry" (LEW-17879-1) NASA Tech Briefs, Vol. 31, No. 6 (June 2007), page 48, and in the immediately preceding article, "Hand-Held Units for Short-Range Wireless Biotelemetry" (LEW-17483-1). The differences between what is reported here and what was reported in the cited prior articles lie in proposed design features and a proposed mode of operation. In a specific system of the type now proposed, the sensor unit would comprise mainly a capacitive MEMS pressure sensor located in the annular region of a loop antenna (more specifically, a square spiral inductor/ antenna), all fabricated as an integral unit on a high-resistivity silicon chip. The capacitor electrodes, the spiral inductor/antenna, and the conductor lines interconnecting them would all be made of gold. The dimensions of the sensor unit have been estimated to be about 110.4 mm. The external garment-mounted powering/ interrogating unit would include a multi-turn loop antenna and signal-processing circuits. During operation, this external unit would be positioned in proximity to the implanted or ingested unit to provide for near-field, inductive coupling between the loop antennas, which we have as the primary and secondary windings of an electrical transformer.
Wireless event-recording device with identification codes
NASA Technical Reports Server (NTRS)
Watters, David G. (Inventor); Huestis, David L. (Inventor); Bahr, Alfred J. (Inventor)
2004-01-01
A wireless recording device can be interrogated to determine its identity and its state. The state indicates whether a particular physical or chemical event has taken place. In effect, the physical or chemical event is recorded by the device. The identity of the device allows it to be distinguished from a number of similar devices. Thus the sensor device may be used in an array of devices that can be probed by a wireless interrogation unit. The device tells the interrogator who it is and what state it is in. The interrogator can thus easily identify particular items in an array that have reached a particular condition.
Walking on by Is Just the Beginning: Dialogically Interrogating Face-Work
ERIC Educational Resources Information Center
Herakova, Liliana L.
2016-01-01
Courses: Introduction to Communication Studies, Interpersonal Communication, Nonverbal Communication. Objectives: After completing this single-class activity, students should be able to (1) describe and interpret face-work as a communicative act that both reflects and constructs identity, (2) explain the concept of intersectionality in basic…
Displaying Knowledge through Interrogatives in Student-Initiated Sequences
ERIC Educational Resources Information Center
Solem, Marit Skarbø
2016-01-01
This article presents an analysis of student initiatives in whole-class interactions. While prior research on question-answer sequences in classroom interactions has shown students to be rather passive recipients of knowledge, this article focuses on aspects of classroom interaction where students take a more active role. Following a conversation…
Teamwork through Team Building: Face-to-Face to Online
ERIC Educational Resources Information Center
Staggers, Julie; Garcia, Susan; Nagelhout, Ed
2008-01-01
This article describes the ways the authors incorporated team-building activities into our online business writing courses by interrogating the ways that kinesthetic learning translates into the electronic realm. The authors review foundational theories of team building, including Cog's Ladder and Tuckman's Stages, and offer sample exercises they…
Multi-Party, Whole-Body Interactions in Mathematical Activity
ERIC Educational Resources Information Center
Ma, Jasmine Y.
2017-01-01
This study interrogates the contributions of multi-party, whole-body interactions to students' collaboration and negotiation of mathematics ideas in a task setting called walking scale geometry, where bodies in interaction became complex resources for students' emerging goals in problem solving. Whole bodies took up overlapping roles representing…
Genome-scale expression studies and comprehensive loss-of-function genetic screens have focused almost exclusively on the highest confidence candidate genes. Here, we describe a strategy for characterizing the lower confidence candidates identified by such approaches.
Visual Snapshots of Intracellular Kinase Activity At The Onset of Mitosis
Dai, Zhaohua; Dulyaninova, Natalya G.; Kumar, Sanjai; Bresnick, Anne R.; Lawrence, David S.
2007-01-01
Summary Visual snapshots of intracellular kinase activity can be acquired with exquisite temporal control using a light-activatable (caged) sensor, thereby providing a means to interrogate enzymatic activity at any point during the cell division cycle. Robust protein kinase activity transpires just prior to, but not immediately following, nuclear envelope breakdown (NEB). Furthermore, kinase activity is required for progression from prophase into metaphase. Finally, the application of selective protein kinase C (PKC) inhibitors, in combination with the caged sensor, correlates the action of the PKC β isoform with subsequent NEB. PMID:18022564
NASA Technical Reports Server (NTRS)
Goordial, J.; Davila, A.; Greer, C. W.; Cannam, R.; DiRuggiero, J.; McKay, C. P.; Whyte, L. G.
2016-01-01
This study represents the first metagenomic interrogation of Antarctic permafrost and polar cryptoendolithic microbial communities. The results underlie two different habitability conditions in the same location under extreme cold and dryness: the permafrost habitat where viable microbial life and activity is questionable, and the cryptoendolithic habitat which contains organisms capable of growth under the extreme conditions of the Antarctic Dry Valleys.
Fiber optic systems for colorimetry and scattered colorimetry
NASA Astrophysics Data System (ADS)
Mignani, Anna G.; Mencaglia, Andrea A.; Ciaccheri, Leonardo
2005-09-01
An innovative series of optical fiber sensors based on spectroscopic interrogation is presented. The sensors are custom-designed for a wide range of applications, including gasoline colorimetry, chromium monitoring of sewage, museum lighting control, for use with a platform for interrogating an array of absorption-based chemical sensors, as well as for color and turbidity measurements. Two types of custom-design instrumentation have been developed, both making use of LED light sources and a low-cost optical fiber spectrometer to perform broadband spectral measurements in the visible spectral range. The first was designed especially to address color-based sensors, while the second assessed the combined color and turbidity of edible liquids such as olive oil. Both are potentially exploitable in other industrial and environmental applications.
NASA Astrophysics Data System (ADS)
Wang, Fuyin; Xie, Jiehui; Hu, Zhengliang; Xiong, Shuidong; Luo, Hong; Hu, Yongming
2014-05-01
Study of fiber optic extrinsic Fabry-Pérot sensors utilizing state-of-the-art MEMS technology mostly focus on sensor fabrication for various applications, while the signal interrogation is still insatiable to current application. In this paper, we propose a white light path matched differential interferometer dynamic sensing system utilizing phase generated carrier demodulation scheme. A step motor with a movable mirror and a fiber-wound piezoelectric transducer string are used to act path matching and phase modulation respectively. Experimental results show that the sensing signal could be correctly recovered with low distortion and the phase noise spectrum level is less than -100 dB re. rad/√Hz above 2.5 kHz.
ERIC Educational Resources Information Center
Enoh, Tabe Florence Ako
2000-01-01
Examined the syntactic behavior of wh-operators in Kenyang, a Bantu language. Following Chomsky's minimalist programme (1993, 1995), describes the nature of universal grammar and accounts for certain specific parametrized variations of that system into the nature of interrogative structures in Kenyang. (Author/VWL)
The Use of Molecular Techniques at Hazardous Waste Sites
It is clear that typical protocols used for soil analysis would certainly fail to adequately interrogate ground-water treatment systems unless they were substantially modified. The modifications found necessary to compensate for the low biomass include molecular tools and techniq...
Achievable Performance and Effective Interrogator Design for SAW RFID Sensor Tags
NASA Technical Reports Server (NTRS)
Barton, Richard J.
2011-01-01
For many NASA missions, remote sensing is a critical application that supports activities such as environmental monitoring, planetary science, structural shape and health monitoring, non-destructive evaluation, etc. The utility of the remote sensing devices themselves is greatly increased if they are passive that is, they do not require any on-board power supply such as batteries and if they can be identified uniquely during the sensor interrogation process. Additional passive sensor characteristics that enable greater utilization in space applications are small size and weight, long read ranges with low interrogator power, ruggedness, and operability in extreme environments (vacuum, extreme high/low temperature, high radiation, etc.) In this paper, we consider one very promising passive sensor technology, called surface acoustic wave (SAW) radio-frequency identification (RFID), that satisfies all of these criteria. Although SAW RFID tags have great potential for use in numerous space-based remote sensing applications, the limited collision resolution capability of current generation tags limits the performance in a cluttered sensing environment. That is, as more SAW-based sensors are added to the environment, numerous tag responses are superimposed at the receiver and decoding all or even a subset of the telemetry becomes increasingly difficult. Background clutter generated by reflectors other than the sensors themselves is also a problem, as is multipath interference and signal distortion, but the limiting factor in many remote sensing applications can be expected to be tag mutual interference. This problem may be greatly mitigated by proper design of the SAW tag waveform, but that remains an open research problem, and in the meantime, several other related questions remain to be answered including: What are the fundamental relationships between tag parameters such as bit-rate, time-bandwidth-product, SNR, and achievable collision resolution? What are the differences in optimal or near-optimal interrogator designs between noise-limited environments and interference-limited environments? What are the performance characteristics of different interrogator designs in term of parameters such as transmitter power level, range, and number of interfering tags? In this paper, we present the results of a research effort aimed at providing at least partial answers to all of these questions.
NASA Astrophysics Data System (ADS)
Kouroussis, Georges; Kinet, Damien; Mendoza, Edgar; Dupuy, Julien; Moeyaert, Véronique; Caucheteur, Christophe
2016-07-01
Structural health and operation monitoring are of growing interest in the development of railway networks. Conventional systems of infrastructure monitoring already exist (e.g. axle counters, track circuits) but present some drawbacks. Alternative solutions are therefore studied and developed. In this field, optical fiber sensors, and more particularly fiber Bragg grating (FBG) sensors, are particularly relevant due to their immunity to electromagnetic fields and simple wavelength-division-multiplexing capability. Field trials conducted up to now have demonstrated that FBG sensors provide useful information about train composition, positioning, speed, acceleration and weigh-in-motion estimations. Nevertheless, for practical deployment, cost-effectiveness should be ensured, specifically at the interrogator side that has also to be fast (>1 kHz repetition rate), accurate (∼1 pm wavelength shift) and reliable. To reach this objective, we propose in this paper to associate a low cost and high-speed interrogator coupled with an adequate signal-processing algorithm to dynamically monitor cascaded wavelength-multiplexed FBGs and to accurately capture the parameters of interest for railway traffic monitoring. This method has been field-tested with a Redondo Optics Inc. interrogator based on the well-known edge-filter demodulation technique. To determine the train speed from the raw data, a dominant frequency analysis has been implemented. Using this original method, we show that we can retrieve the speed of the trains, even when the time history strain signature is strongly affected by the measurement noise. The results are assessed by complimentary data obtained from a spectrometer-based FBG interrogator.
A pacemaker magnet check alone is sufficient for the majority of patients postpacemaker implant.
Jones, Michael A; Wong, Kelvin C K; Qureshi, Norman; Rajappan, Kim; Bashir, Yaver; Betts, Timothy R
2014-12-01
Patients postpacemaker implant can undergo a full assessment by pacing system programmer (PSP) or a magnet check. The former takes longer, but provides more detailed information; a magnet-mode assessment is faster, but provides only capture data in an asynchronous pacing mode. A magnet-mode assessment alone may be sufficient in most cases, and current clinical practice varies considerably. A retrospective single-center assessment of all pacemaker implants receiving PSP and magnet checks between September 2009 and April 2010. Patient records were reviewed. The results of PSP and magnet checks and any subsequent device-related management were noted. A total of 168 patients underwent pacemaker implantation, magnet-mode assessment, and then PSP interrogation during this period. Magnet-mode assessment revealed a problem in only one patient-failure of atrial capture, leading to subsequent atrial lead repositioning. None of the remaining 167 patients have a serious problem at PSP interrogation; six had minor issues at PSP check, none of which required repeat surgical intervention. The magnet-mode test only provides information on lead capture in an asynchronous pacing mode, which is the most essential data postoperatively. Our study has suggested that a magnet-mode assessment without PSP interrogation may be sufficient in the immediate postimplant assessment of these patients. Routine postimplant PSP interrogation is time consuming, labor intensive, and adds only minimal additional benefit to the safe management of these patients above and beyond a magnet check, coupled with informed assessment of the associated electrocardiogram/rhythm strip, clinical examination, and chest x-ray. ©2014 Wiley Periodicals, Inc.
Portable-Beacon Landing System for Helicopters
NASA Technical Reports Server (NTRS)
Davis, Thomas J.; Clary, George R.; Chisholm, John P.; Macdonald, Stanley L.
1987-01-01
Prototype beacon landing system (BLS) allows helicopters to make precise landings in all weather. BLS easily added to existing helicopter avionic equipment and readily deployed at remote sites. Small and light, system employs X-band radar and digital processing. Variety of beams pulsed sequentially by ground station after initial interrogation by weather radar of approaching helicopter. Airborne microprocessor processes pulses to determine glide slope, course deviation, and range.
Damage Detection/Locating System Providing Thermal Protection
NASA Technical Reports Server (NTRS)
Woodard, Stanley E. (Inventor); Jones, Thomas W. (Inventor); Taylor, Bryant D. (Inventor); Qamar, A. Shams (Inventor)
2010-01-01
A damage locating system also provides thermal protection. An array of sensors substantially tiles an area of interest. Each sensor is a reflective-surface conductor having operatively coupled inductance and capacitance. A magnetic field response recorder is provided to interrogate each sensor before and after a damage condition. Changes in response are indicative of damage and a corresponding location thereof.
New Non-Intrusive Inspection Technologies for Nuclear Security and Nonproliferation
NASA Astrophysics Data System (ADS)
Ledoux, Robert J.
2015-10-01
Comprehensive monitoring of the supply chain for nuclear materials has historically been hampered by non-intrusive inspection systems that have such large false alarm rates that they are impractical in the flow of commerce. Passport Systems, Inc. (Passport) has developed an active interrogation system which detects fissionable material, high Z material, and other contraband in land, sea and air cargo. Passport's design utilizes several detection modalities including high resolution imaging, passive radiation detection, effective-Z (EZ-3D™) anomaly detection, Prompt Neutrons from Photofission (PNPF), and Nuclear Resonance Fluorescence (NRF) isotopic identification. These technologies combine to: detect fissionable, high-Z, radioactive and contraband materials, differentiate fissionable materials from high-Z shielding materials, and isotopically identify actinides, Special Nuclear Materials (SNM), and other contraband (e.g. explosives, drugs, nerve agents). Passport's system generates a 3-D image of the scanned object which contains information such as effective-Z and density, as well as a 2-D image and isotopic and fissionable information for regions of interest.
Characterization of lipid films by an angle-interrogation surface plasmon resonance imaging device.
Liu, Linlin; Wang, Qiong; Yang, Zhong; Wang, Wangang; Hu, Ning; Luo, Hongyan; Liao, Yanjian; Zheng, Xiaolin; Yang, Jun
2015-04-01
Surface topographies of lipid films have an important significance in the analysis of the preparation of giant unilamellar vesicles (GUVs). In order to achieve accurately high-throughput and rapidly analysis of surface topographies of lipid films, a homemade SPR imaging device is constructed based on the classical Kretschmann configuration and an angle interrogation manner. A mathematical model is developed to accurately describe the shift including the light path in different conditions and the change of the illumination point on the CCD camera, and thus a SPR curve for each sampling point can also be achieved, based on this calculation method. The experiment results show that the topographies of lipid films formed in distinct experimental conditions can be accurately characterized, and the measuring resolution of the thickness lipid film may reach 0.05 nm. Compared with existing SPRi devices, which realize detection by monitoring the change of the reflective-light intensity, this new SPRi system can achieve the change of the resonance angle on the entire sensing surface. Thus, it has higher detection accuracy as the traditional angle-interrogation SPR sensor, with much wider detectable range of refractive index. Copyright © 2015 Elsevier B.V. All rights reserved.
Failing ethics 101: psychologists, the U.S. military establishment, and human rights.
Boyd, J Wesley; LoCicero, Alice; Malowney, Monica; Aldis, Rajendra; Marlin, Robert P
2014-01-01
The American Psychological Association (APA) has long maintained a close, even symbiotic, relationship with the Department of Defense (DOD) and the Veterans Administration (VA). Herein we highlight these close ties and describe psychologists' participation in interrogations by U.S. military and intelligence entities. We then review the APA's statements about the permissibility of psychologist participation in the interrogation and torture of suspected terrorists. These issues are significant in and of themselves and because the VA and DOD have been described as "growth careers" for psychologists of the future (1). Additionally, the Health Care Personnel Delivery System allows the drafting of civilian clinical psychologists into military service even in the absence of a general draft. In light of psychologists' extensive involvement in the interrogation process of suspected terrorists, and the possibility that psychologists without prior military experience may be drafted, we wondered how much psychologists have been taught about their ethical duties should they find themselves in military settings. The results of our pilot study of U.S. psychology graduate students, which assessed their knowledge of military ethics, raise concerns that psychologists receive inadequate formal training in these matters. This may leave psychologists vulnerable to misinformation about proper ethical conduct in their future work.
Pinas, Johan E.; Henkel, Christiaan V.; Augustijn, Dieuwertje; Hooykaas, Paul J. J.; van der Zaal, Bert J.
2017-01-01
The rapidly growing world population has a greatly increasing demand for plant biomass, thus creating a great interest in the development of methods to enhance the growth and biomass accumulation of crop species. In this study, we used zinc finger artificial transcription factor (ZF-ATF)-mediated genome interrogation to manipulate the growth characteristics and biomass of Arabidopsis plants. We describe the construction of two collections of Arabidopsis lines expressing fusions of three zinc fingers (3F) to the transcriptional repressor motif EAR (3F-EAR) or the transcriptional activator VP16 (3F-VP16), and the characterization of their growth characteristics. In total, six different 3F-ATF lines with a consistent increase in rosette surface area (RSA) of up to 55% were isolated. For two lines we demonstrated that 3F-ATF constructs function as dominant in trans acting causative agents for an increase in RSA and biomass, and for five larger plant lines we have investigated 3F-ATF induced transcriptomic changes. Our results indicate that genome interrogation can be used as a powerful tool for the manipulation of plant growth and biomass and that it might supply novel cues for the discovery of genes and pathways involved in these properties. PMID:28358915
Tol, Niels van; Rolloos, Martijn; Pinas, Johan E; Henkel, Christiaan V; Augustijn, Dieuwertje; Hooykaas, Paul J J; van der Zaal, Bert J
2017-01-01
The rapidly growing world population has a greatly increasing demand for plant biomass, thus creating a great interest in the development of methods to enhance the growth and biomass accumulation of crop species. In this study, we used zinc finger artificial transcription factor (ZF-ATF)-mediated genome interrogation to manipulate the growth characteristics and biomass of Arabidopsis plants. We describe the construction of two collections of Arabidopsis lines expressing fusions of three zinc fingers (3F) to the transcriptional repressor motif EAR (3F-EAR) or the transcriptional activator VP16 (3F-VP16), and the characterization of their growth characteristics. In total, six different 3F-ATF lines with a consistent increase in rosette surface area (RSA) of up to 55% were isolated. For two lines we demonstrated that 3F-ATF constructs function as dominant in trans acting causative agents for an increase in RSA and biomass, and for five larger plant lines we have investigated 3F-ATF induced transcriptomic changes. Our results indicate that genome interrogation can be used as a powerful tool for the manipulation of plant growth and biomass and that it might supply novel cues for the discovery of genes and pathways involved in these properties.
NASA Astrophysics Data System (ADS)
Diaz, Aaron A.; Burghard, Brion J.; Skorpik, James R.; Shepard, Chester L.; Samuel, Todd J.; Pappas, Richard A.
2003-07-01
The Pacific Northwest National Laboratory (PNNL) has developed a portable, battery-operated, handheld ultrasonic device that provides non-invasive container interrogation and material identification capabilities. The technique governing how the acoustic inspection device (AID) functions, involves measurements of ultrasonic pulses (0.1 to 5 MHz) that are launched into a container or material. The return echoes from these pulses are analyzed in terms of time-of-flight and frequency content to extract physical property measurements (the acoustic velocity and attenuation coefficient) of the material under test. The AID performs an automated analysis of the return echoes to identify the material, and detect contraband in the form of submerged packages and concealed compartments in liquid filled containers and solid-form commodities. An inspector can quickly interrogate outwardly innocuous commodity items such as shipping barrels, tanker trucks, and metal ingots. The AID can interrogate container sizes ranging from approximately 6 inches in diameter to over 96 inches in diameter and allows the inspector to sort liquid and material types into groups of like and unlike; a powerful method for discovering corrupted materials or miss-marked containers co-mingled in large shipments. This manuscript describes the functionality, capabilities and measurement methodology of the technology as it relates to homeland security applications.
Interrogative suggestibility in opiate users.
Murakami, A; Edelmann, R J; Davis, P E
1996-09-01
The present study investigated interrogative suggestibility in opiate users. A group of patients undergoing a methadone detoxification programme in an in-patient drug treatment unit (Detox group, n = 21), and a group of residents who had come off drugs and were no longer suffering from withdrawal syndrome (Rehab group, n = 19) were compared on interrogative suggestibility and various other psychological factors. Significant differences were found between the two groups, with the Detox group having more physical and psychological problems, and a higher total suggestibility score in comparison with the Rehab group. These findings are discussed in relation to the context of police interrogations and the reliability of confessions made by suspects and witnesses dependent on opiates.
L-C Measurement Acquisition Method for Aerospace Systems
NASA Technical Reports Server (NTRS)
Woodard, Stanley E.; Taylor, B. Douglas; Shams, Qamar A.; Fox, Robert L.
2003-01-01
This paper describes a measurement acquisition method for aerospace systems that eliminates the need for sensors to have physical connection to a power source (i.e., no lead wires) or to data acquisition equipment. Furthermore, the method does not require the sensors to be in proximity to any form of acquisition hardware. Multiple sensors can be interrogated using this method. The sensors consist of a capacitor, C(p), whose capacitance changes with changes to a physical property, p, electrically connected to an inductor, L. The method uses an antenna to broadcast electromagnetic energy that electrically excites one or more inductive-capacitive sensors via Faraday induction. This method facilitates measurements that were not previously possible because there was no practical means of providing power and data acquisition electrical connections to a sensor. Unlike traditional sensors, which measure only a single physical property, the manner in which the sensing element is interrogated simultaneously allows measurement of at least two unrelated physical properties (e.g., displacement rate and fluid level) by using each constituent of the L-C element. The key to using the method for aerospace applications is to increase the distance between the L-C elements and interrogating antenna; develop all key components to be non-obtrusive and to develop sensing elements that can easily be implemented. Techniques that have resulted in increased distance between antenna and sensor will be presented. Fluid-level measurements and pressure measurements using the acquisition method are demonstrated in the paper.
Viewing Marine Bacteria, Their Activity and Response to Environmental Drivers from Orbit
Grimes, D. Jay; Ford, Tim E.; Colwell, Rita R.; Baker-Austin, Craig; Martinez-Urtaza, Jaime; Subramaniam, Ajit; Capone, Douglas G.
2014-01-01
Satellite-based remote sensing of marine microorganisms has become a useful tool in predicting human health risks associated with these microscopic targets. Early applications were focused on harmful algal blooms, but more recently methods have been developed to interrogate the ocean for bacteria. As satellite-based sensors have become more sophisticated and our ability to interpret information derived from these sensors has advanced, we have progressed from merely making fascinating pictures from space to developing process models with predictive capability. Our understanding of the role of marine microorganisms in primary production and global elemental cycles has been vastly improved as has our ability to use the combination of remote sensing data and models to provide early warning systems for disease outbreaks. This manuscript will discuss current approaches to monitoring cyanobacteria and vibrios, their activity and response to environmental drivers, and will also suggest future directions. PMID:24477922
Grimes, D Jay; Ford, Tim E; Colwell, Rita R; Baker-Austin, Craig; Martinez-Urtaza, Jaime; Subramaniam, Ajit; Capone, Douglas G
2014-04-01
Satellite-based remote sensing of marine microorganisms has become a useful tool in predicting human health risks associated with these microscopic targets. Early applications were focused on harmful algal blooms, but more recently methods have been developed to interrogate the ocean for bacteria. As satellite-based sensors have become more sophisticated and our ability to interpret information derived from these sensors has advanced, we have progressed from merely making fascinating pictures from space to developing process models with predictive capability. Our understanding of the role of marine microorganisms in primary production and global elemental cycles has been vastly improved as has our ability to use the combination of remote sensing data and models to provide early warning systems for disease outbreaks. This manuscript will discuss current approaches to monitoring cyanobacteria and vibrios, their activity and response to environmental drivers, and will also suggest future directions.
Commercial Product Activation Using RFID
NASA Technical Reports Server (NTRS)
Jedrey, Thomas
2008-01-01
Radio-frequency identification (RFID) would be used for commercial product activation, according to a proposal. What is new here is the concept of combining RFID with activation - more specifically, using RFID for activating commercial products (principally, electronic ones) and for performing such ancillary functions as tracking individual product units on production lines, tracking shipments, and updating inventories. According to the proposal, an RFID chip would be embedded in each product. The information encoded in the chip would include a unique number for identifying the product. An RFID reader at the point of sale would record the number of the product and would write digital information to the RFID chip for either immediate activation of the product or for later interrogation and processing. To be practical, an RFID product-activation system should satisfy a number of key requirements: the system should be designed to be integrable into the inventory-tracking and the data-processing and -communication infrastructures of businesses along the entire supply chain from manufacture to retail; the system should be resistant to sophisticated hacking; activation codes should be made sufficiently complexity to minimize the probability of activating stolen products; RFID activation equipment at points of sale must be capable to two-way RF communication for the purposes of reading information from, and writing information to, embedded RFID chips; the equipment at points of sale should be easily operable by sales clerks with little or no training; the point-of-sale equipment should verify activation and provide visible and/or audible signals indicating verification or lack thereof; and, the system should be able to handle millions of products per year with minimal human intervention, among other requirements.
Laser-Based Acousto-Optic Uplink Communications Technique
2003-08-18
An apparatus for enabling acousto - optic communication comprising an in-water platform comprising means for emitting an acoustic signal to an acousto ...portion of the first interrogation beam and a second laser beam formed from the reflection of the first interrogation beam off of the acousto - optic interaction... optic interaction zone, an in-air platform comprising the ability for transmitting a first optical interrogation beam, the ability for receiving a
Do Persian Native Speakers Prosodically Mark Wh-in-situ Questions?
Shiamizadeh, Zohreh; Caspers, Johanneke; Schiller, Niels O
2018-02-01
It has been shown that prosody contributes to the contrast between declarativity and interrogativity, notably in interrogative utterances lacking lexico-syntactic features of interrogativity. Accordingly, it may be proposed that prosody plays a role in marking wh-in-situ questions in which the interrogativity feature (the wh-phrase) does not move to sentence-initial position, as, for example, in Persian. This paper examines whether prosody distinguishes Persian wh-in-situ questions from declaratives in the absence of the interrogativity feature in the sentence-initial position. To answer this question, a production experiment was designed in which wh-questions and declaratives were elicited from Persian native speakers. On the basis of the results of previous studies, we hypothesize that prosodic features mark wh-in-situ questions as opposed to declaratives at both the local (pre- and post-wh part) and global level (complete sentence). The results of the current study confirm our hypothesis that prosodic correlates mark the pre-wh part as well as the complete sentence in wh-in-situ questions. The results support theoretical concepts such as the frequency code, the universal dichotomous association between relaxation and declarativity on the one hand and tension and interrogativity on the other, the relation between prosody and pragmatics, and the relation between prosody and encoding and decoding of sentence type.
17 CFR 242.600 - NMS security designation and definitions.
Code of Federal Regulations, 2013 CFR
2013-04-01
...) Interrogation device means any securities information retrieval system capable of displaying transaction reports... with respect to such order; and (v) Immediately and automatically displays information that updates the... security; and (ii) Consolidated last sale information for a security. (14) Consolidated last sale...
17 CFR 242.600 - NMS security designation and definitions.
Code of Federal Regulations, 2014 CFR
2014-04-01
...) Interrogation device means any securities information retrieval system capable of displaying transaction reports... with respect to such order; and (v) Immediately and automatically displays information that updates the... security; and (ii) Consolidated last sale information for a security. (14) Consolidated last sale...
17 CFR 242.600 - NMS security designation and definitions.
Code of Federal Regulations, 2011 CFR
2011-04-01
...) Interrogation device means any securities information retrieval system capable of displaying transaction reports... with respect to such order; and (v) Immediately and automatically displays information that updates the... security; and (ii) Consolidated last sale information for a security. (14) Consolidated last sale...
17 CFR 242.600 - NMS security designation and definitions.
Code of Federal Regulations, 2012 CFR
2012-04-01
...) Interrogation device means any securities information retrieval system capable of displaying transaction reports... with respect to such order; and (v) Immediately and automatically displays information that updates the... security; and (ii) Consolidated last sale information for a security. (14) Consolidated last sale...
Piwnica-Worms, David; Kesarwala, Aparna H; Pichler, Andrea; Prior, Julie L; Sharma, Vijay
2006-11-01
Overexpression of multi-drug resistant P-glycoprotein (Pgp) remains an important barrier to successful chemotherapy in cancer patients and impacts the pharmacokinetics of many important drugs. Pgp is also expressed on the luminal surface of brain capillary endothelial cells wherein Pgp functionally comprises a major component of the blood-brain barrier by limiting central nervous system penetration of various therapeutic agents. In addition, Pgp in brain capillary endothelial cells removes amyloid-beta from the brain. Several single photon emission computed tomography and positron emission tomography radiopharmaceutical have been shown to be transported by Pgp, thereby enabling the noninvasive interrogation of Pgp-mediated transport activity in vivo. Therefore, molecular imaging of Pgp activity may enable noninvasive dynamic monitoring of multi-drug resistance in cancer, guide therapeutic choices in cancer chemotherapy, and identify transporter deficiencies of the blood-brain barrier in Alzheimer's disease.
Technical basis for the use of a correlated neutron source in the uranium neutron coincidence collar
Root, Margaret A.; Menlove, Howard Olsen; Lanza, Richard C.; ...
2017-01-16
Active neutron coincidence systems are commonly used by international inspectorates to verify a material balance across the various stages of the nuclear fuel cycle. The Uranium Neutron Coincidence Collar (UNCL) is one such instrument; it is used to measure the linear density of 235U (g 235U/cm of active length in assembly) in fresh light water reactor fuel in nuclear fuel fabrication facilities. The UNCL and other active neutron interrogation detectors have historically relied on americium lithium ( 241AmLi) sources to induce fission within the sample in question. Californium-252 is under consideration as a possible alternative to the traditional 241AmLi source.more » Finally, this work relied upon a combination of experiments and Monte Carlo simulations to demonstrate the technical basis for the replacement of 241AmLi sources with 252Cf sources by evaluating the statistical uncertainty in the measurements incurred by each source and assessing the penetrability of neutrons from each source for the UNCL.« less
Technical basis for the use of a correlated neutron source in the uranium neutron coincidence collar
DOE Office of Scientific and Technical Information (OSTI.GOV)
Root, Margaret A.; Menlove, Howard Olsen; Lanza, Richard C.
Active neutron coincidence systems are commonly used by international inspectorates to verify a material balance across the various stages of the nuclear fuel cycle. The Uranium Neutron Coincidence Collar (UNCL) is one such instrument; it is used to measure the linear density of 235U (g 235U/cm of active length in assembly) in fresh light water reactor fuel in nuclear fuel fabrication facilities. The UNCL and other active neutron interrogation detectors have historically relied on americium lithium ( 241AmLi) sources to induce fission within the sample in question. Californium-252 is under consideration as a possible alternative to the traditional 241AmLi source.more » Finally, this work relied upon a combination of experiments and Monte Carlo simulations to demonstrate the technical basis for the replacement of 241AmLi sources with 252Cf sources by evaluating the statistical uncertainty in the measurements incurred by each source and assessing the penetrability of neutrons from each source for the UNCL.« less
Campus-Based Student Experiences of Learning Technologies in a First-Year Science Course
ERIC Educational Resources Information Center
Ellis, Robert; Weyers, Mark; Hughes, Jane
2013-01-01
This study reports on an investigation into the campus-based experience of university students studying mammalian physiology that was significantly supported with learning technologies. The design of the course enabled the students to interrogate the key ideas that they came across in their lectures and laboratories through online activities which…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Adhikary, Suraj; Eichman, Brandt F.
DNA glycosylases specialized for the repair of alkylation damage must identify, with fine specificity, a diverse array of subtle modifications within DNA. The current mechanism involves damage sensing through interrogation of the DNA duplex, followed by more specific recognition of the target base inside the active site pocket. To better understand the physical basis for alkylpurine detection, we determined the crystal structure of Schizosaccharomyces pombe Mag1 (spMag1) in complex with DNA and performed a mutational analysis of spMag1 and the close homologue from Saccharomyces cerevisiae (scMag). Despite strong homology, spMag1 and scMag differ in substrate specificity and cellular alkylation sensitivity,more » although the enzymological basis for their functional differences is unknown. We show that Mag preference for 1,N{sup 6}-ethenoadenine ({var_epsilon}A) is influenced by a minor groove-interrogating residue more than the composition of the nucleobase-binding pocket. Exchanging this residue between Mag proteins swapped their {var_epsilon}A activities, providing evidence that residues outside the extrahelical base-binding pocket have a role in identification of a particular modification in addition to sensing damage.« less
NASA Astrophysics Data System (ADS)
Wu, Jiangling; Huang, Yu; Bian, Xintong; Li, DanDan; Cheng, Quan; Ding, Shijia
2016-10-01
In this work, a custom-made intensity-interrogation surface plasmon resonance imaging (SPRi) system has been developed to directly detect a specific sequence of BCR/ABL fusion gene in chronic myelogenous leukemia (CML). The variation in the reflected light intensity detected from the sensor chip composed of gold islands array is proportional to the change of refractive index due to the selective hybridization of surface-bound DNA probes with target ssDNA. SPRi measurements were performed with different concentrations of synthetic target DNA sequence. The calibration curve of synthetic target sequence shows a good relationship between the concentration of synthetic target and the change of reflected light intensity. The detection limit of this SPRi measurement could approach 10.29 nM. By comparing SPRi images, the target ssDNA and non-complementary DNA sequence are able to be distinguished. This SPRi system has been applied for assay of BCR/ABL fusion gene extracted from real samples. This nucleic acid-based SPRi biosensor therefore offers an alternative high-effective, high-throughput label-free tool for DNA detection in biomedical research and molecular diagnosis.
Bashor, Caleb J; Horwitz, Andrew A; Peisajovich, Sergio G; Lim, Wendell A
2010-01-01
The living cell is an incredibly complex entity, and the goal of predictively and quantitatively understanding its function is one of the next great challenges in biology. Much of what we know about the cell concerns its constituent parts, but to a great extent we have yet to decode how these parts are organized to yield complex physiological function. Classically, we have learned about the organization of cellular networks by disrupting them through genetic or chemical means. The emerging discipline of synthetic biology offers an additional, powerful approach to study systems. By rearranging the parts that comprise existing networks, we can gain valuable insight into the hierarchical logic of the networks and identify the modular building blocks that evolution uses to generate innovative function. In addition, by building minimal toy networks, one can systematically explore the relationship between network structure and function. Here, we outline recent work that uses synthetic biology approaches to investigate the organization and function of cellular networks, and describe a vision for a synthetic biology toolkit that could be used to interrogate the design principles of diverse systems.
The evolution and exploitation of the fiber-optic hydrophone
NASA Astrophysics Data System (ADS)
Hill, David J.
2007-07-01
In the late 1970s one of the first applications identified for fibre-optic sensing was the fibre-optic hydrophone. It was recognised that the technology had the potential to provide a cost effective solution for large-scale arrays of highly sensitive hydrophones which could be interrogated over large distances. Consequently both the United Kingdom and United States navies funded the development of this sonar technology to the point that it is now deployed on submarines and as seabed arrays. The basic design of a fibre-optic hydrophone has changed little; comprising a coil of optical fibre wound on a compliant mandrel, interrogated using interferometric techniques. Although other approaches are being investigated, including the development of fibre-laser hydrophones, the interferometric approach remains the most efficient way to create highly multiplexed arrays of acoustic sensors. So much so, that the underlying technology is now being exploited in civil applications. Recently the exploration and production sector of the oil and gas industry has begun funding the development of fibre-optic seismic sensing using seabed mounted, very large-scale arrays of four component (three accelerometers and a hydrophone) packages based upon the original technology developed for sonar systems. This has given new impetus to the development of the sensors and the associated interrogation systems which has led to the technology being adopted for other commercial uses. These include the development of networked in-road fibre-optic Weigh-in-Motion sensors and of intruder detection systems which are able to acoustically monitor long lengths of border, on both land and at sea. After two decades, the fibre-optic hydrophone and associated technology has matured and evolved into a number of highly capable sensing solutions used by a range of industries.
An Automated High-Throughput System to Fractionate Plant Natural Products for Drug Discovery
Tu, Ying; Jeffries, Cynthia; Ruan, Hong; Nelson, Cynthia; Smithson, David; Shelat, Anang A.; Brown, Kristin M.; Li, Xing-Cong; Hester, John P.; Smillie, Troy; Khan, Ikhlas A.; Walker, Larry; Guy, Kip; Yan, Bing
2010-01-01
The development of an automated, high-throughput fractionation procedure to prepare and analyze natural product libraries for drug discovery screening is described. Natural products obtained from plant materials worldwide were extracted and first prefractionated on polyamide solid-phase extraction cartridges to remove polyphenols, followed by high-throughput automated fractionation, drying, weighing, and reformatting for screening and storage. The analysis of fractions with UPLC coupled with MS, PDA and ELSD detectors provides information that facilitates characterization of compounds in active fractions. Screening of a portion of fractions yielded multiple assay-specific hits in several high-throughput cellular screening assays. This procedure modernizes the traditional natural product fractionation paradigm by seamlessly integrating automation, informatics, and multimodal analytical interrogation capabilities. PMID:20232897
Ruggiero, Anthony J.
2005-05-03
An integrated optical capillary electrophoresis system for analyzing an analyte. A modulated optical pump beam impinges on an capillary containing the analyte/buffer solution which is separated by electrophoresis. The thermally-induced change in the index of refraction of light in said electrophoresis capillary is monitored using an integrated micro-interferometer. The interferometer includes a first interferometer arm intersecting the electrophoresis capillary proximate the excitation beam and a second, reference interferometer arm. Changes in index of refraction in the analyte measured by interrogating the interferometer state using white light interferometry and a phase-generated carrier demodulation technique. Background thermo-optical activity in the buffer solution is cancelled by splitting the pump beam and exciting pure buffer solution in a second section of capillary where it crosses the reference arm of the interferometer.
Educing Information - Interrogation: Science and Art, Foundations for the Future
2006-12-01
television. Law school was (and remains) even less informative with respect to such questions. Most lawyers and judges learn the “art” (but not the...Maryland; its fi rst priority was to train interrogators and the students learned personality analysis, ways of infl uencing people and making friends...J.D. Simmons College School for Health Studies June 2006 Abstract The interrogation of suspects, witnesses, and others is an essential source of
Calkins, Laura
2010-01-01
Using medical literature citations, Congressional hearings, and declassified documents this paper examines the uses of pharmaceuticals in the interrogation of vulnerable populations. From the use of IV relaxants on criminal suspects during the 1920s to the Global War on Terror, the nexus of drugs, testing, and interrogations will be explored in both the domestic and international contexts.
NASA Astrophysics Data System (ADS)
Díaz, Camilo A. R.; Marques, Carlos A. F.; Domingues, M. Fátima F.; Ribeiro, Moisés. R. N.; Neto, Anselmo F.; Pontes, Maria J.; André, Paulo S.; Antunes, Paulo F. C.
2018-02-01
This paper presents a simple, compact, stable and inexpensive in-line solution based on catastrophic fuse effect micro-cavity interferometers for edge-filter strain interrogation of a fiber Bragg grating sensor. By using a commercial spliced machine and recycling damage fiber for the catastrophic fuse effect it is possible to construct a micro-cavity with high contrast of more than 20dB, and acceptable half free spectra range (FSR) around 13nm of interrogation range. The strain from 0 to 1440μStrain of the FBG sensor is measured with evidences of high repeatability and stability. Future work will investigate the use of the proposed method for applications requiring higher interrogation rates.
Beauregard, Eric; Deslauriers-Varin, Nadine; St-Yves, Michel
2010-09-01
Most studies of confessions have looked at the influence of individual factors, neglecting the potential interactions between these factors and their impact on the decision to confess or not during an interrogation. Classification and regression tree analyses conducted on a sample of 624 convicted sex offenders showed that certain factors related to the offenders (e.g., personality, criminal career), victims (e.g., sex, relationship to offender), and case (e.g., time of day of the crime) were related to the decision to confess or not during the police interrogation. Several interactions were also observed between these factors. Results will be discussed in light of previous findings and interrogation strategies for sex offenders.
Chinese-English Automation and Computer Technology Dictionary, Volume 2.
1980-08-01
The purpose of the series is to provide rapid reference tools for translators, abstractors, and research analysts concerned with scientific and...tansuo search; searching; 25 exploration; explore: research ; hunting; trace; seek tansuo dianxian tracer wire 26 884 tansuxd . ., heuristic 01 tansuofa...xunwen -v Ij ;I system interrogation 22 xitong yanjiu A f IC system research 23 xitong yinqyong chengxiud -A, i M 1 R N- #1 , system utility program 24
Fully Passive Wireless Acquisition of Neuropotentials
NASA Astrophysics Data System (ADS)
Schwerdt, Helen N.
The ability to monitor electrophysiological signals from the sentient brain is requisite to decipher its enormously complex workings and initiate remedial solutions for the vast amount of neurologically-based disorders. Despite immense advancements in creating a variety of instruments to record signals from the brain, the translation of such neurorecording instrumentation to real clinical domains places heavy demands on their safety and reliability, both of which are not entirely portrayed by presently existing implantable recording solutions. In an attempt to lower these barriers, alternative wireless radar backscattering techniques are proposed to render the technical burdens of the implant chip to entirely passive neurorecording processes that transpire in the absence of formal integrated power sources or powering schemes along with any active circuitry. These radar-like wireless backscattering mechanisms are used to conceive of fully passive neurorecording operations of an implantable microsystem. The fully passive device potentially manifests inherent advantages over current wireless implantable and wired recording systems: negligible heat dissipation to reduce risks of brain tissue damage and minimal circuitry for long term reliability as a chronic implant. Fully passive neurorecording operations are realized via intrinsic nonlinear mixing properties of the varactor diode. These mixing and recording operations are directly activated by wirelessly interrogating the fully passive device with a microwave carrier signal. This fundamental carrier signal, acquired by the implant antenna, mixes through the varactor diode along with the internal targeted neuropotential brain signals to produce higher frequency harmonics containing the targeted neuropotential signals. These harmonics are backscattered wirelessly to the external interrogator that retrieves and recovers the original neuropotential brain signal. The passive approach removes the need for internal power sources and may alleviate heat trauma and reliability issues that limit practical implementation of existing implantable neurorecorders.
Dynamic Analysis with Fibre Optic Sensors for Structural Health Monitoring
2006-10-01
cracked thick aluminum plate repaired with a bonded composite patch using transmission-type extrinsic Fabry – Perot interferometric optical fiber...and optical filtering have been used to demodulate returned Bragg signals. Due to the passive nature of the interrogation unit, system bandwidth is
Nimbus 6 Random Access Measurement System applications experiments
NASA Technical Reports Server (NTRS)
Cote, C. E. (Editor); Taylor, R. (Editor); Gilbert, E. (Editor)
1982-01-01
The advantages of a technique in which data collection platforms randomly transmit signal to a polar orbiting satellite, thus eliminating satellite interrogation are demonstrated in investigations of the atmosphere; oceanographic parameters; Arctic regions and ice conditions; navigation and position location; and data buoy development.
Crafting Miniature Students in the Early Years: Schooling for Desirable Childhoods in East Asia
ERIC Educational Resources Information Center
Lee, I.-Fang; Yelland, Nicola J.
2017-01-01
This paper explores the concept of miniature students to interrogate the ways in which early childhood care and education systems in East Asian countries are being constructed. Experiences drawn from working in the Hong Kong education system and observations of teaching and researching in Hong Kong have enabled an analysis about the ways in which…
Development of the QA/QC Procedures for a Neutron Interrogation System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Obhodas, Jasmina; Sudac, Davorin; Valkovic, Vladivoj
In order to perform QA/QC procedures for a system dedicated to the neutron interrogation of objects for the presence of threat materials one needs to perform measurements of reference materials (RM) having the same (or similar) atomic ratios as real materials. It is well known that explosives, drugs, and various other benign materials, contain chemical elements such as hydrogen, oxygen, carbon and nitrogen in distinctly different quantities. For example, a high carbon-to-oxygen ratio (C/O) is characteristic of drugs. Explosives can be differentiated by measurement of both C/O and nitrogen-to-oxygen (N/O) ratios. The C/N ratio of the chemical warfare agents, coupledmore » with the measurement of elements such as fluorine and phosphorus, clearly differentiate them from the conventional explosives. Correlations between theoretical values and experimental results obtained in laboratory conditions for C/O and N/C ratios of simulants of hexogen (RDX), TNT, DLM2, TATP, cocaine, heroin, yperite, tetranitromethane, peroxide methylethyl-ketone, nitromethane and ethyleneglycol dinitrate are presented. (authors)« less
Non-contact tamper sensing by electronic means
Gritton, Dale G.
1993-01-01
A tamper-sensing system for an electronic tag 10 which is to be fixed to a surface 11 of an article 12, the tamper-sensing system comprising a capacitor having two non-contacting, capacitively-coupled elements 16, 19. Fixing of the body to the article will establish a precise location of the capacitor elements 16 and 19 relative to each other. When interrogated, the tag will generate a tamper-sensing signal having a value which is a function of the amount of capacity of the capacitor elements. The precise relative location of the capacitor elements cannot be duplicated if the tag is removed and affixed to a surrogate article having a fiducial capacitor element 19 fixed thereto. A very small displacement, in the order of 2-10 microns, of the capacitor elements relative to each other if the tag body is removed and fixed to a surrogate article will result in the tamper-sensing signal having a different, and detectable, value when the tag is interrogated.
Grant, A. M.; Richard, Y.; Deland, E.; Després, N.; de Lorenzi, F.; Dagenais, A.; Buteau, M.
1997-01-01
The Autocontrol methodology has been developed in order to support the optimisation of decision-making and the use of resources in the context of a clinical unit. The theoretical basis relates to quality assurance and information systems and is influenced by management and cognitive research in the health domain. The methodology uses population rather than individual decision making and because of its dynamic feedback design promises to have rapid and profound effect on practice. Most importantly the health care professional is the principle user of the Autocontrol system. In this methodology we distinguish three types of evidence necessary for practice change: practice based or internal evidence, best evidence derived from the literature or external evidence concerning the practice in question, and process based evidence on how to optimise the process of practice change. The software used by the system is of the executive decision support type which facilitates interrogation of large databases. The Autocontrol system is designed to interrogate the data of the patient medical record however the latter often lacks data on concomitant resource use and this must be supplemented. This paper reviews the Autocontrol methodology and gives examples from current studies. PMID:9357733
Grant, A M; Richard, Y; Deland, E; Després, N; de Lorenzi, F; Dagenais, A; Buteau, M
1997-01-01
The Autocontrol methodology has been developed in order to support the optimisation of decision-making and the use of resources in the context of a clinical unit. The theoretical basis relates to quality assurance and information systems and is influenced by management and cognitive research in the health domain. The methodology uses population rather than individual decision making and because of its dynamic feedback design promises to have rapid and profound effect on practice. Most importantly the health care professional is the principle user of the Autocontrol system. In this methodology we distinguish three types of evidence necessary for practice change: practice based or internal evidence, best evidence derived from the literature or external evidence concerning the practice in question, and process based evidence on how to optimise the process of practice change. The software used by the system is of the executive decision support type which facilitates interrogation of large databases. The Autocontrol system is designed to interrogate the data of the patient medical record however the latter often lacks data on concomitant resource use and this must be supplemented. This paper reviews the Autocontrol methodology and gives examples from current studies.
Effectiveness of false correction strategy on science reading comprehension
NASA Astrophysics Data System (ADS)
Ghent, Cynthia Anne
False-correction reading strategy theoretically prompted college students to activate their prior knowledge when provided false statements linked to a portion of their biology textbook. This strategy is based in elaborative interrogation theory, which suggests that prompting readers to answer interrogatives about text students are reading increases their comprehension of that text. These interrogatives always asked "why" statements pulled from a text, one sentence in length, were "true." True statements in this study based on a text were converted by the experimenter into false statements, one sentence in length. Students were requested to rewrite each statement (n=12) on average every 200 words in a text as they were reading, converting each false statement into a true statement. These students outperformed other students requested to reread the same biology text twice (an established placebo-control strategy). These students, in turn, outperformed still other students reading an unrelated control text taken from the same textbook used only to establish a prior knowledge baseline for all students included in this study. Students participating in this study were enrolled students in an undergraduate introductory general biology course designed for non-majors. A three-group, posttest-only, randomized experimental control-group design was used to prevent pretest activation of students' prior knowledge thus increasing chances of producing evidence of false-correction effectiveness and to begin augmenting potential generalizability to science classrooms. Students' (n=357) general biology knowledge, verbal ability, and attempts to use the false correction strategy were collected and analyzed. Eight of the participants were interviewed by the researcher in a first attempt in this domain to collect data on participants' points of view about the strategy. The results of this study are not yet recommended for use in authentic school settings as further research is indicated.
Contributing to shipping container security: can passive sensors bring a solution?
Janssens-Maenhout, G; De Roo, F; Janssens, W
2010-02-01
Illicit trafficking of fissionable material in container cargoes is recognized as a potential weakness in Nuclear Security. Triggered by the attacks of 11 September 2001, measures were undertaken to enhance maritime security in extension to the Safety Of Life At Sea Convention and in line with the US Container Security Initiatives. Effective detection techniques are needed that allow the inspector to intercept illicit trafficking of nuclear weapons components or components of other nuclear explosive devices. Many security measures focus on active interrogation of the container content by X-ray scan, which might be extended with the newly developed tagged neutron inspection system. Both active interrogation techniques can, with the current huge volume of container traffic, only be applied to a limited number of selected containers. The question arises whether a passive detection technique can offer an alternative solution. This study investigates if containers equipped with a small passive detector will register during transport the neutron irradiation by fissionable material such as plutonium in a measurable way. In practice, 4/5 of the containers are about 1/8 filled with hydrogenous material and undergo a typical 2 months route. For this reference case, it was found that the most compatible passive detector would be an activation foil of iridium. Monte-Carlo simulations showed that for the reference case the activity of a 250 microm thin foil with 6 cm(2) cross-section would register 1.2 Bq when it is irradiated by a significant quantity of Reactor-Grade PuO(2). However this activity drops with almost two orders of magnitude for other fillings and other isotopic compositions and forms of the Pu-source. The procedure of selecting the target material for Pu detection is detailed with the theoretical methods, in order to be useful for other applications. Moreover the value of such additional passive sensors for securing maritime container transport is situated within the global framework of the First, Second and Third Line of Defense against illicit trafficking. Copyright 2009 Elsevier Ltd. All rights reserved.
GPS-Squitter capacity analysis
NASA Astrophysics Data System (ADS)
Orlando, Vincent A.; Harman, William H.
1994-05-01
GPS-Squitter is a system concept that merges the capabilities of Automatic Dependent Surveillance (ADS) and the Mode S beacon radar. The result is an integrated concept for seamless surveillance and data link that permits equipped aircraft to participate in ADS and/or beacon ground environments. This concept offers many possibilities for transition from a beacon to an ADS-based environment. This report provides the details of the techniques used to estimate GPS-Squitter surveillance and data link capacity. Surveillance capacity of airborne aircraft is calculated for the omni and six-sector ground stations. Next, the capacity of GPS-Squitter for surface traffic is estimated. The interaction between airborne and surface operations is addressed to show the independence of these systems. Air ground data link capacity for GPS-Squitter is estimated, together with an estimate of the use of the Mode S link to support other ground surveillance and data link activities as well as TCAS operation. The analysis indicates the low transponder occupancy resulting from the total effect of these activities. Low occupancy is a key requirement in avoiding interference with the operation of the current ATCRBS and future Mode S interrogators.
2014-09-17
AFRL-OSR-VA-TR-2014-0255 ADAPTIVE PIEZOELECTRIC CIRCUITRY SENSOR NETWORK KON -WELL WANG MICHIGAN UNIV ANN ARBOR Final Report 09/17/2014 DISTRIBUTION A...Harmonics Interrogation for Structural Damage Detection FA9550-11-1-0072 Kon -Well Wang and Jiong Tang The Regents of the University of Michigan, 3003...mechanism. These efforts have yielded a complete methodology of adaptive high-frequency piezoelectric self-sensing interrogation. None None None SAR Kon
Thick-tissue bioreactor as a platform for long-term organotypic culture and drug delivery.
Markov, Dmitry A; Lu, Jenny Q; Samson, Philip C; Wikswo, John P; McCawley, Lisa J
2012-11-07
We have developed a novel, portable, gravity-fed, microfluidics-based platform suitable for optical interrogation of long-term organotypic cell culture. This system is designed to provide convenient control of cell maintenance, nutrients, and experimental reagent delivery to tissue-like cell densities housed in a transparent, low-volume microenvironment. To demonstrate the ability of our Thick-Tissue Bioreactor (TTB) to provide stable, long-term maintenance of high-density cellular arrays, we observed the morphogenic growth of human mammary epithelial cell lines, MCF-10A and their invasive variants, cultured under three-dimensional (3D) conditions inside our system. Over the course of 21 days, these cells typically develop into hollow "mammospheres" if cultured in standard 3D Matrigel. This complex morphogenic process requires alterations in a variety of cellular functions, including degradation of extracellular matrix that is regulated by cell-produced matrix proteinases. For our "drug" delivery testing and validation experiments we have introduced proteinase inhibitors into the fluid supply system, and we observed both reduced proteinase activity and inhibited cellular morphogenesis. The size inhibition results correlated well with the overall proteinase activities of the tested cells.
Baù, Marco; Ferrari, Marco; Ferrari, Vittorio
2017-01-01
A technique for contactless electromagnetic interrogation of AT-cut quartz piezoelectric resonator sensors is proposed based on a primary coil electromagnetically air-coupled to a secondary coil connected to the electrodes of the resonator. The interrogation technique periodically switches between interleaved excitation and detection phases. During the excitation phase, the resonator is set into vibration by a driving voltage applied to the primary coil, whereas in the detection phase, the excitation signal is turned off and the transient decaying response of the resonator is sensed without contact by measuring the voltage induced back across the primary coil. This approach ensures that the readout frequency of the sensor signal is to a first order approximation independent of the interrogation distance between the primary and secondary coils. A detailed theoretical analysis of the interrogation principle based on a lumped-element equivalent circuit is presented. The analysis has been experimentally validated on a 4.432 MHz AT-cut quartz crystal resonator, demonstrating the accurate readout of the series resonant frequency and quality factor over an interrogation distance of up to 2 cm. As an application, the technique has been applied to the measurement of liquid microdroplets deposited on a 4.8 MHz AT-cut quartz crystal. More generally, the proposed technique can be exploited for the measurement of any physical or chemical quantities affecting the resonant response of quartz resonator sensors. PMID:28574459
Baù, Marco; Ferrari, Marco; Ferrari, Vittorio
2017-06-02
A technique for contactless electromagnetic interrogation of AT-cut quartz piezoelectric resonator sensors is proposed based on a primary coil electromagnetically air-coupled to a secondary coil connected to the electrodes of the resonator. The interrogation technique periodically switches between interleaved excitation and detection phases. During the excitation phase, the resonator is set into vibration by a driving voltage applied to the primary coil, whereas in the detection phase, the excitation signal is turned off and the transient decaying response of the resonator is sensed without contact by measuring the voltage induced back across the primary coil. This approach ensures that the readout frequency of the sensor signal is to a first order approximation independent of the interrogation distance between the primary and secondary coils. A detailed theoretical analysis of the interrogation principle based on a lumped-element equivalent circuit is presented. The analysis has been experimentally validated on a 4.432 MHz AT-cut quartz crystal resonator, demonstrating the accurate readout of the series resonant frequency and quality factor over an interrogation distance of up to 2 cm. As an application, the technique has been applied to the measurement of liquid microdroplets deposited on a 4.8 MHz AT-cut quartz crystal. More generally, the proposed technique can be exploited for the measurement of any physical or chemical quantities affecting the resonant response of quartz resonator sensors.
Overcoming Innocents' Naiveté: Pre-interrogation Decision-making Among Innocent Suspects.
Scherr, Kyle C; Alberts, Kimberly M; Franks, Andrew S; Hawkins, Ian
2016-07-01
Suspects, especially innocent ones, are highly susceptible to waiving their interrogation rights. This research tested the ability of two strategies to overcome innocent suspects' willingness to waive their rights. One strategy was based on the social influence of scarcity (i.e., not constraining the pre-interrogation time limit). The other strategy focused on disrupting individuals' cognitive fluency during the decision-making process (i.e., violating their induced expectation of offering a waiver). Disrupting innocent individuals' cognitive fluency increased their willingness to invoke their rights and, notably, was not qualified by interactions with any other factors. However, scarcity did not influence individuals' pre-interrogation decision-making. Results also further established the association between innocent individuals' naïve mindset and their willingness to waive their rights - specifically, innocents' willingness to waive their rights increased with the strength of their just world beliefs. The theoretical and applied implications of these findings are discussed. The importance and benefit of reforming pre-interrogation protocols using fair and feasible strategies that would disrupt suspects' cognitive fluency are emphasized. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Harish, Achar V; Varghese, Bibin; Rao, Babu; Balasubramaniam, Krishnan; Srinivasan, Balaji
2015-07-01
Use of in-fiber Fabry-Perot (FP) filters based on fiber Bragg gratings as both sensor as well as an interrogator for enhancing the detection limit of elastic wave sensing is investigated in this paper. The sensitivity of such a demodulation scheme depends on the spectral discrimination of the sensor and interrogator gratings. Simulations have shown that the use of in-fiber FP filters with high finesse provide better performance in terms of sensitivity compared to the demodulation using fiber Bragg gratings. Based on these results, a dynamic interrogator capable of sensing acoustic waves with amplitude of less than 1 micro-strain over frequencies of 10 kHz to several 100 kHz has been implemented. Frequency response of the fiber Bragg gratings in the given experimental setup has been compared to that of the conventional piezo sensors demonstrating that fiber Bragg gratings can be used over a relatively broad frequency range. Dynamic interrogator has been packaged in a compact box without any degradation in its performance. Copyright © 2015 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eleon, Cyrille; Passard, Christian; Hupont, Nicolas
2015-07-01
Nuclear measurements are used at AREVA NC/La Hague for the monitoring of spent fuel reprocessing. The process control is based on gamma-ray spectroscopy, passive neutron counting and active neutron interrogation, and gamma transmission measurements. The main objectives are criticality and safety, online process monitoring, and the determination of the residual fissile mass and activities in the metallic waste remained after fuel shearing and dissolution (empty hulls, grids, end pieces), which are put in radioactive waste drums before compaction. The whole monitoring system is composed of eight measurement stations which will be described in this paper. The main measurement stations no.more » 1, 3 and 7 are needed for criticality control. Before fuel element shearing for dissolution, station no. 1 allows determining the burn-up of the irradiated fuel by gamma-ray spectroscopy with HP Ge (high purity germanium) detectors. The burn-up is correlated to the {sup 137}Cs and {sup 134}Cs gamma emission rates. The fuel maximal mass which can be loaded in one bucket of the dissolver is estimated from the lowest burn-up fraction of the fuel element. Station no. 3 is dedicated to the control of the correct fuel dissolution, which is performed with a {sup 137}Cs gamma ray measurement with a HP Ge detector. Station no. 7 allows estimating the residual fissile mass in the drums filled with the metallic residues, especially in the hulls, from passive neutron counting (spontaneous fission and alpha-n reactions) and active interrogation (fission prompt neutrons induced by a pulsed neutron generator) with proportional {sup 3}He detectors. The measurement stations have been validated for the reprocessing of Uranium Oxide (UOX) fuels with a burn-up rate up to 60 GWd/t. This paper presents a brief overview of the current status of the nuclear measurement stations. (authors)« less
Detection of biological molecules using chemical amplification and optical sensors
Van Antwerp, William Peter; Mastrototaro, John Joseph
2000-01-01
Methods are provided for the determination of the concentration of biological levels of polyhydroxylated compounds, particularly glucose. The methods utilize an amplification system that is an analyte transducer immobilized in a polymeric matrix, where the system is implantable and biocompatible. Upon interrogation by an optical system, the amplification system produces a signal capable of detection external to the skin of the patient. Quantitation of the analyte of interest is achieved by measurement of the emitted signal.
Optoelectronic system and apparatus for connection to biological systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Okandan, Murat; Nielson, Gregory N.
The present invention relates to a biological probe structure, as well as apparatuses, systems, and methods employing this structure. In particular embodiments, the structure includes a hermetically sealed unit configured to receive and transmit one or more optical signals. Furthermore, the structure can be implanted subcutaneously and interrogated externally. In this manner, a minimally invasive method can be employed to detect, treat, and/or assess the biological target. Additional methods and systems are also provided.
Detection of biological molecules using chemical amplification and optical sensors
Van Antwerp, William Peter; Mastrototaro, John Joseph
2004-10-12
Methods are provided for the determination of the concentration of biological levels of polyhydroxylated compounds, particularly glucose. The methods utilize an amplification system that is an analyte transducer immobilized in a polymeric matrix, where the system is implantable and biocompatible. Upon interrogation by an optical system, the amplification system produces a signal capable of detection external to the skin of the patient. Quantitation of the analyte of interest is achieved by measurement of the emitted signal.
Theorising Quality in Higher Education
ERIC Educational Resources Information Center
Morley, Louise
2004-01-01
Britain now has the most heavily regulated higher education system in the world and institutions must deliver best educational value. This book explores the political and psychic economy of quality assurance in higher education and interrogates the discourse and practices associated with the audit culture in Britain. Following Acknowledgements and…
Electromagnetic characterization of layered biaxial media is a critical step in the design of modern low observable (LO) coatings, and with the...the flexibility they provide for control over magnitude, phase, and polarization of the material systems response to interrogating electromagnetic (EM
Towards a knowledge-based system to assist the Brazilian data-collecting system operation
NASA Technical Reports Server (NTRS)
Rodrigues, Valter; Simoni, P. O.; Oliveira, P. P. B.; Oliveira, C. A.; Nogueira, C. A. M.
1988-01-01
A study is reported which was carried out to show how a knowledge-based approach would lead to a flexible tool to assist the operation task in a satellite-based environmental data collection system. Some characteristics of a hypothesized system comprised of a satellite and a network of Interrogable Data Collecting Platforms (IDCPs) are pointed out. The Knowledge-Based Planning Assistant System (KBPAS) and some aspects about how knowledge is organized in the IDCP's domain are briefly described.
Judicial astrology in theory and practice in later medieval Europe.
Carey, Hilary M
2010-06-01
Interrogations and elections were two branches of Arabic judicial astrology made available in Latin translation to readers in western Europe from the twelfth century. Through an analysis of the theory and practice of interrogations and elections, including the writing of the Jewish astrologer Sahl b. Bishr, this essay considers the extent to which judicial astrology was practiced in the medieval west. Consideration is given to historical examples of interrogations and elections mostly from late medieval English manuscripts. These include the work of John Dunstaple (ca. 1390-1453), the musician and astrologer who is known have served at the court of John, duke of Bedford. On the basis of the relatively small number of surviving historical horoscopes, it is argued that the practice of interrogations and elections lagged behind the theory.
The interrogation decision-making model: A general theoretical framework for confessions.
Yang, Yueran; Guyll, Max; Madon, Stephanie
2017-02-01
This article presents a new model of confessions referred to as the interrogation decision-making model . This model provides a theoretical umbrella with which to understand and analyze suspects' decisions to deny or confess guilt in the context of a custodial interrogation. The model draws upon expected utility theory to propose a mathematical account of the psychological mechanisms that not only underlie suspects' decisions to deny or confess guilt at any specific point during an interrogation, but also how confession decisions can change over time. Findings from the extant literature pertaining to confessions are considered to demonstrate how the model offers a comprehensive and integrative framework for organizing a range of effects within a limited set of model parameters. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Phase-Sensitive Surface Plasmon Resonance Sensors: Recent Progress and Future Prospects
Deng, Shijie; Wang, Peng; Yu, Xinglong
2017-01-01
Surface plasmon resonance (SPR) is an optical sensing technique that is capable of performing real-time, label-free and high-sensitivity monitoring of molecular interactions. SPR biosensors can be divided according to their operating principles into angle-, wavelength-, intensity- and phase-interrogated devices. With their complex optical configurations, phase-interrogated SPR sensors generally provide higher sensitivity and throughput, and have thus recently emerged as prominent biosensing devices. To date, several methods have been developed for SPR phase interrogation, including heterodyne detection, polarimetry, shear interferometry, spatial phase modulation interferometry and temporal phase modulation interferometry. This paper summarizes the fundamentals of phase-sensitive SPR sensing, reviews the available methods for phase interrogation of these sensors, and discusses the future prospects for and trends in the development of this technology. PMID:29206182
NASA Technical Reports Server (NTRS)
Miller, James G.
1994-01-01
In this Progress Report, we describe our continuing research activities concerning the development and implementation of advanced ultrasonic nondestructive evaluation methods applied to the inspection and characterization of complex composite structures. We explore the feasibility of implementing medical linear array imaging technology as a viable ultrasonic-based nondestructive evaluation method to inspect and characterize complex materials. As an initial step toward the application of linear array imaging technology to the interrogation of a wide range of complex composite structures, we present images obtained using an unmodified medical ultrasonic imaging system of two epoxy-bonded aluminum plate specimens, each with intentionally disbonded regions. These images are compared with corresponding conventional ultrasonic contact transducer measurements in order to assess whether these images can detect disbonded regions and provide information regarding the nature of the disbonded region. We present a description of a standoff/delay fixture which has been designed, constructed, and implemented on a Hewlett-Packard SONOS 1500 medical imaging system. This standoff/delay fixture, when attached to a 7.5 MHz linear array probe, greatly enhances our ability to interrogate flat plate specimens. The final section of this Progress Report describes a woven composite plate specimen that has been specially machined to include intentional flaws. This woven composite specimen will allow us to assess the feasibility of applying linear array imaging technology to the inspection and characterization of complex textile composite materials. We anticipate the results of this on-going investigation may provide a step toward the development of a rapid, real-time, and portable method of ultrasonic inspection and characterization based on linear array technology.
2011-01-01
remote sensing , such as Fourier-transform infrared spectroscopy, has limited recognition specificity because of atmospheric pressure broadening. Active interrogation techniques promise much greater chemical recognition that can overcome the limits imposed by atmospheric pressure broadening. Here we introduce infrared - terahertz (IR/THz) double resonance spectroscopy as an active means of chemical remote sensing that retains recognition specificity through rare, molecule-unique coincidences between IR molecular absorption and a line-tunable CO2
User Data on the Social Web: Authorship, Agency, and Appropriation
ERIC Educational Resources Information Center
Reyman, Jessica
2013-01-01
Social web services catalog users' activities across the Internet, aggregating, analyzing, and selling a vast array of user data to be used largely for consumer profiling and target marketing. This article interrogates the tacit agreements and terms-of-use policies that govern who owns user data, how it circulates, and how it can be used. Relying…
ERIC Educational Resources Information Center
Stahelin, Nicolas
2017-01-01
In this case study of an environmental education (EE) program run in public schools of Rio de Janeiro, I use a constructivist spatial analytic to interrogate notions of space, place, and territory in critical EE practices. I examine the connections between socioenvironmental relations, counter-hegemonic political activity, and education by delving…
Sexual Learning and the Seaside: Relocating the "Dirty Weekend" and Teenage Girls' Sexuality
ERIC Educational Resources Information Center
Hemingway, Judy
2006-01-01
This paper explores the geographical constitution of the "dirty weekend" and teenage girls' sexuality by interrogating the cultural habitus of the seaside resort. It reidentifies the littoral pleasure zone as an active agent in sexual learning and disrupts taken-for-granted inscriptions of the seaside as an inert backdrop against which…
Valuing Production Values: A "Do It Yourself" Media Production Club
ERIC Educational Resources Information Center
Jenson, Jennifer; Dahya, Negin; Fisher, Stephanie
2014-01-01
In this paper, we identify how and why digital media production can contribute to the active participation of children in education and also consider how much of the existing work in this area is framed as a "miraculous" answer to educational challenges without critical interrogation of either the process or product. To begin, we…
NASA Astrophysics Data System (ADS)
Bromberger, B.; Bar, D.; Brandis, M.; Dangendorf, V.; Goldberg, M. B.; Kaufmann, F.; Mor, I.; Nolte, R.; Schmiedel, M.; Tittelmeier, K.; Vartsky, D.; Wershofen, H.
2012-03-01
An air cargo inspection system combining two nuclear reaction based techniques, namely Fast-Neutron Resonance Radiography and Dual-Discrete-Energy Gamma Radiography is currently being developed. This system is expected to allow detection of standard and improvised explosives as well as special nuclear materials. An important aspect for the applicability of nuclear techniques in an airport inspection facility is the inventory and lifetimes of radioactive isotopes produced by the neutron radiation inside the cargo, as well as the dose delivered by these isotopes to people in contact with the cargo during and following the interrogation procedure. Using MCNPX and CINDER90 we have calculated the activation levels for several typical inspection scenarios. One example is the activation of various metal samples embedded in a cotton-filled container. To validate the simulation results, a benchmark experiment was performed, in which metal samples were activated by fast-neutrons in a water-filled glass jar. The induced activity was determined by analyzing the gamma spectra. Based on the calculated radioactive inventory in the container, the dose levels due to the induced gamma radiation were calculated at several distances from the container and in relevant time windows after the irradiation, in order to evaluate the radiation exposure of the cargo handling staff, air crew and passengers during flight. The possibility of remanent long-lived radioactive inventory after cargo is delivered to the client is also of concern and was evaluated.
ERIC Educational Resources Information Center
Thompson, Kate; Reimann, Peter
2010-01-01
A classification system that was developed for the use of agent-based models was applied to strategies used by school-aged students to interrogate an agent-based model and a system dynamics model. These were compared, and relationships between learning outcomes and the strategies used were also analysed. It was found that the classification system…
Sharrock, R; Gudjonsson, G H
1993-05-01
The main purpose of this study was to investigate the relationship between interrogative suggestibility and previous convictions among 108 defendants in criminal trials, using a path analysis technique. It was hypothesized that previous convictions, which may provide defendants with interrogative experiences, would correlate negatively with 'shift' as measured by the Gudjonsson Suggestibility Scale (Gudjonsson, 1984a), after intelligence and memory had been controlled for. The hypothesis was partially confirmed and the theoretical and practical implications of the findings are discussed.
Subthreshold neutron interrogator for detection of radioactive materials
Evans, Michael L.; Menlove, Howard O.; Baker, Michael P.
1980-01-01
A device for detecting fissionable material such as uranium in low concentrations by interrogating with photoneutrons at energy levels below 500 keV, and typically about 26 keV. Induced fast neutrons having energies above 500 keV by the interrogated fissionable material are detected by a liquid scintillator or recoil proportional counter which is sensitive to the induced fast neutrons. Since the induced fast neutrons are proportional to the concentration of fissionable material, detection of induced fast neutrons indicate concentration of the fissionable material.
Velmurugu, Yogambigai; Vivas, Paula; Connolly, Mitchell; Kuznetsov, Serguei V; Rice, Phoebe A; Ansari, Anjum
2018-02-28
The dynamics and mechanism of how site-specific DNA-bending proteins initially interrogate potential binding sites prior to recognition have remained elusive for most systems. Here we present these dynamics for Integration Host factor (IHF), a nucleoid-associated architectural protein, using a μs-resolved T-jump approach. Our studies show two distinct DNA-bending steps during site recognition by IHF. While the faster (∼100 μs) step is unaffected by changes in DNA or protein sequence that alter affinity by >100-fold, the slower (1-10 ms) step is accelerated ∼5-fold when mismatches are introduced at DNA sites that are sharply kinked in the specific complex. The amplitudes of the fast phase increase when the specific complex is destabilized and decrease with increasing [salt], which increases specificity. Taken together, these results indicate that the fast phase is non-specific DNA bending while the slow phase, which responds only to changes in DNA flexibility at the kink sites, is specific DNA kinking during site recognition. Notably, the timescales for the fast phase overlap with one-dimensional diffusion times measured for several proteins on DNA, suggesting that these dynamics reflect partial DNA bending during interrogation of potential binding sites by IHF as it scans DNA.
Advanced analysis techniques for uranium assay
DOE Office of Scientific and Technical Information (OSTI.GOV)
Geist, W. H.; Ensslin, Norbert; Carrillo, L. A.
2001-01-01
Uranium has a negligible passive neutron emission rate making its assay practicable only with an active interrogation method. The active interrogation uses external neutron sources to induce fission events in the uranium in order to determine the mass. This technique requires careful calibration with standards that are representative of the items to be assayed. The samples to be measured are not always well represented by the available standards which often leads to large biases. A technique of active multiplicity counting is being developed to reduce some of these assay difficulties. Active multiplicity counting uses the measured doubles and triples countmore » rates to determine the neutron multiplication (f4) and the product of the source-sample coupling ( C ) and the 235U mass (m). Since the 35U mass always appears in the multiplicity equations as the product of Cm, the coupling needs to be determined before the mass can be known. A relationship has been developed that relates the coupling to the neutron multiplication. The relationship is based on both an analytical derivation and also on empirical observations. To determine a scaling constant present in this relationship, known standards must be used. Evaluation of experimental data revealed an improvement over the traditional calibration curve analysis method of fitting the doubles count rate to the 235Um ass. Active multiplicity assay appears to relax the requirement that the calibration standards and unknown items have the same chemical form and geometry.« less
Sip, Kamila E.; Carmel, David; Marchant, Jennifer L.; Li, Jian; Petrovic, Predrag; Roepstorff, Andreas; McGregor, William B.; Frith, Christopher D.
2013-01-01
Does the brain activity underlying the production of deception differ depending on whether or not one believes their deception can be detected? To address this question, we had participants commit a mock theft in a laboratory setting, and then interrogated them while they underwent functional MRI (fMRI) scanning. Crucially, during some parts of the interrogation participants believed a lie-detector was activated, whereas in other parts they were told it was switched-off. We were thus able to examine the neural activity associated with the contrast between producing true vs. false claims, as well as the independent contrast between believing that deception could and could not be detected. We found increased activation in the right amygdala and inferior frontal gyrus (IFG), as well as the left posterior cingulate cortex (PCC), during the production of false (compared to true) claims. Importantly, there was a significant interaction between the effects of deception and belief in the left temporal pole and right hippocampus/parahippocampal gyrus, where activity increased during the production of deception when participants believed their false claims could be detected, but not when they believed the lie-detector was switched-off. As these regions are associated with binding socially complex perceptual input and memory retrieval, we conclude that producing deceptive behavior in a context in which one believes this deception can be detected is associated with a cognitively taxing effort to reconcile contradictions between one's actions and recollections. PMID:23382715
8 CFR 343b.4 - Applicant outside of United States.
Code of Federal Regulations, 2011 CFR
2011-01-01
... the certificate. When such interrogation is not practicable, or is not conducted because the... interrogation by a State Department representative. When forwarding the certificate in such a case, the...
AN/UPX-41(C) Test Data Analysis of Impacts to Secondary Surveillance Radars.
DOT National Transportation Integrated Search
2015-02-01
In 2012, the Navy requested spectrum certification for the shipboard AN/UPX-41(C) Digital Interrogator System, Software Version 5.5 with Mode 5. Current operating conditions for the Navys AN/UPX-41(C) are the same as restrictions imposed on the AN...
Evolutionary Psychology and False Confession
ERIC Educational Resources Information Center
Bering, Jesse M.; Shackelford, Todd K.
2005-01-01
This paper presents comments on Kassin's review, (see record 2005-03019-002) of the psychology of false confessions. The authors note that Kassin's review makes a compelling argument for the need for legal reform in police interrogation practices. Because his work strikes at the heart of the American criminal justice system--its fairness--the…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-25
..., 2011. Three respondents provided comments on the interim rule. II. Discussion and Analysis A summary of... Comment: Three respondents provided comments supporting the idea that establishing an effective system of... by reiterating this language in the DFARS. C. Clarity of Definitions Comment: One respondent...
Race and Assessment Practice in South Africa: Understanding Black Academic Experience
ERIC Educational Resources Information Center
Jawitz, Jeff
2012-01-01
Despite efforts to transform the racialised system of higher education in South Africa inherited from apartheid, there has been little research published that interrogates the relationship between race and the experience of academic staff within the South African higher education environment. Drawing on critical discourse analysis and critical…
Immunogenomics: a foundation for intelligent immune design.
Holt, Robert A
2015-11-19
The complexity of the immune system is now being interrogated using methodologies that generate extensive multi-dimensional data. Effective collection, integration and interpretation of these data remain difficult, but overcoming these important challenges will provide new insights into immune function and opportunities for the rational design of new immune interventions.
Interim Update to the AN/UPX-41(C) Spectrum Certification Conditions (SPS-18778/1).
DOT National Transportation Integrated Search
2015-11-01
In 2012, the Navy requested spectrum certification for the shipboard AN/UPX-41(C) Digital Interrogator System, Software Version 5.5 with Mode 5. Current operating conditions for the Navys AN/UPX-41(C) are the same as restrictions imposed on the AN...
Fragmentation and Interrogation as an Approach to Integration
ERIC Educational Resources Information Center
Wallick, Karl; Zaretsky, Michael
2010-01-01
This article tracks the generative role of research and fragmentation as a means for integrating technology and form within an architecture technology lecture class and a co-requisite design studio. The complexity of teaching building systems integration within a design studio context is achieved by removing any expectation of building design…
The Philippine Department of Education: Challenges of Policy Implementation amidst Corruption
ERIC Educational Resources Information Center
Reyes, Vicente Chua
2010-01-01
This inquiry interrogates the experiences of local implementation actors of the Philippine Department of Education as they navigate through reform efforts within systemic corruption. Departing from dominant analytical paradigms centred on patron-client frameworks, the article introduces the typology of complex linkages where local actors play…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Renslow, Ryan S.; Babauta, Jerome T.; Majors, Paul D.
2014-03-01
In order to fully understand electrochemically active biofilms and the limitations to their scale-up in industrial biofilm reactors, a complete picture of the microenvironments inside the biofilm is needed. Nuclear magnetic resonance (NMR) techniques are ideally suited for the study of biofilms and for probing their microenvironments because these techniques allow for non-invasive interrogation and in situ monitoring with high resolution. By combining NMR with simultaneous electrochemical techniques, it is possible to sustain and study live electrochemically active biofilms. Here, we introduce a novel biofilm microreactor system that allows for simultaneous electrochemical and NMR techniques (EC-NMR) at the microscale. Microreactorsmore » were designed with custom radiofrequency resonator coils, which allowed for NMR measurements of biofilms growing on polarized gold electrodes. For an example application of this system, we grew Geobacter sulfurreducens biofilms. NMR was used to investigate growth media flow velocities, which were compared to simulated laminar flow, and electron donor concentrations inside the biofilms. We use Monte Carlo error analysis to estimate standard deviations of the electron donor concentration measurements within the biofilm. The EC-NMR biofilm microreactor system can ultimately be used to correlate extracellular electron transfer rates with metabolic reactions and explore extracellular electron transfer mechanisms.« less
Achievable Performance and Effective Interrogator Design for SAW RFID Sensor Tags
NASA Technical Reports Server (NTRS)
Barton Richard J.
2012-01-01
For many NASA missions, remote sensing is a critical application that supports activities such as environmental monitoring, planetary science, structural shape and health monitoring, non-destructive evaluation, etc. The utility of the remote sensing devices themselves is greatly increased if they are passive V that is, they do not require any on-board power supply such as batteries V and if they can be identified uniquely during the sensor interrogation process. Additional passive sensor characteristics that enable greater utilization in space applications are small size and weight, long read ranges with low interrogator power, ruggedness, and operability in extreme environments (vacuum, extreme high/low temperature, high radiation, etc.) In this paper, we consider one very promising passive sensor technology, called surface acoustic wave (SAW) radio-frequency identification (RFID), that satisfies all of these criteria. In general, RFID is a method of identifying items using radio waves to interrogate tags encoded with a unique identifier that are affixed to the items of interest. In the case of passive tags, only the interrogator, which transmits power to the tags in the form of radio-frequency electromagnetic radiation, requires access to a power supply. Passive RFID technologies are used today in many applications, including asset tracking and management, security and access control, and remote sensing. To date, most of the development and application in RFID technology has focused on either asset/inventory tracking and control or security and access control because these are the largest commercial application areas. Recently however, there has been growing interest in using passive RFID technology for remote sensing applications, and SAW devices are at the forefront of RFID sensing technology development. Although SAW RFID tags have great potential for use in numerous space-based remote sensing applications, the limited collision resolution capability of current generation tags limits the performance in a cluttered sensing environment. That is, as more SAW-based sensors are added to the environment, numerous tag responses are superimposed at the receiver and decoding all or even a subset of the telemetry becomes increasingly difficult. Background clutter generated by reflectors other than the sensors themselves is also a problem, as is multipath interference and signal distortion, but the limiting factor in many remote sensing applications can be expected to be tag mutual interference. This problem may be greatly mitigated by proper design of the SAW tag waveform, but that remains an open research problem, and in the meantime, several other related questions remain to be answered including: (1) What are the fundamental relationships between tag parameters such as bit-rate, time-bandwidth-product, SNR, and achievable collision resolution? (2) What are the differences in optimal or near-optimal interrogator designs between noise-limited environments and interference-limited environments? (3) What are the performance characteristics of different interrogator designs in term of parameters such as transmitter power level, range, and number of interfering tags? In this paper, we will present the results of a research effort aimed at providing at least partial answers to all of these questions.
Santarelli, G; Audoin, C; Makdissi, A; Laurent, P; Dick, G J; Clairon, A
1998-01-01
Atomic frequency standards using trapped ions or cold atoms work intrinsically in a pulsed mode. Theoretically and experimentally, this mode of operation has been shown to lead to a degradation of the frequency stability due to the frequency noise of the interrogation oscillator. In this paper a physical analysis of this effect has been made by evaluating the response of a two-level atom to the interrogation oscillator phase noise in Ramsey and multi-Rabi interrogation schemes using a standard quantum mechanical approach. This response is then used to calculate the degradation of the frequency stability of a pulsed atomic frequency standard such as an atomic fountain or an ion trap standard. Comparison is made to an experimental evaluation of this effect in the LPTF Cs fountain frequency standard, showing excellent agreement.
Interrogation of a ring-resonator ultrasound sensor using a fiber Mach-Zehnder interferometer.
Peternella, Fellipe Grillo; Ouyang, Boling; Horsten, Roland; Haverdings, Michael; Kat, Pim; Caro, Jacob
2017-12-11
We experimentally demonstrate an interrogation procedure of a ring-resonator ultrasound sensor using a fiber Mach-Zehnder interferometer (MZI). The sensor comprises a silicon ring resonator (RR) located on a silicon-oxide membrane, designed to have its lowest vibrational mode in the MHz range, which is the range of intravascular ultrasound (IVUS) imaging. Ultrasound incident on the membrane excites its vibrational mode and as a result induces a modulation of the resonance wavelength of the RR, which is a measure of the amplitude of the ultrasound waves. The interrogation procedure developed is based on the mathematical description of the interrogator operation presented in Appendix A, where we identify the amplitude of the angular deflection Φ 0 on the circle arc periodically traced in the plane of the two orthogonal interrogator voltages, as the principal sensor signal. Interrogation is demonstrated for two sensors with membrane vibrational modes at 1.3 and 0.77 MHz, by applying continuous wave ultrasound in a wide pressure range. Ultrasound is detected at a pressure as low as 1.2 Pa. Two optical path differences (OPDs) of the MZI are used. Thus, different interference conditions of the optical signals are defined, leading to a higher apparent sensitivity for the larger OPD, which is accompanied by a weaker signal, however. Independent measurements using the modulation method yield a resonance modulation per unit of pressure of 21.4 fm/Pa (sensor #1) and 103.8 fm/Pa (sensor #2).
Detection of biological molecules using boronate-based chemical amplification and optical sensors
Van Antwerp, William Peter; Mastrototaro, John Joseph; Lane, Stephen M.; Satcher, Jr., Joe H.; Darrow, Christopher B.; Peyser, Thomas A.; Harder, Jennifer
1999-01-01
Methods are provided for the determination of the concentration of biological levels of polyhydroxylated compounds, particularly glucose. The methods utilize an amplification system that is an analyte transducer immobilized in a polymeric matrix, where the system is implantable and biocompatible. Upon interrogation by an optical system, the amplification system produces a signal capable of detection external to the skin of the patient. Quantitation of the analyte of interest is achieved by measurement of the emitted signal.
Detection of biological molecules using boronate-based chemical amplification and optical sensors
Van Antwerp, William Peter; Mastrototaro, John Joseph; Lane, Stephen M.; Satcher, Jr., Joe H.; Darrow, Christopher B.; Peyser, Thomas A.; Harder, Jennifer
2004-06-15
Methods are provided for the determination of the concentration of biological levels of polyhydroxylated compounds, particularly glucose. The methods utilize an amplification system that is an analyte transducer immobilized in a polymeric matrix, where the system is implantable and biocompatible. Upon interrogation by an optical system, the amplification system produces a signal capable of detection external to the skin of the patient. Quantitation of the analyte of interest is achieved by measurement of the emitted signal.
Moss, Britney L; Elhammali, Adnan; Fowlkes, Tiffanie; Gross, Shimon; Vinjamoori, Anant; Contag, Christopher H; Piwnica-Worms, David
2012-09-07
Full understanding of the biological significance of negative feedback processes requires interrogation at multiple scales as follows: in single cells, cell populations, and live animals in vivo. The transcriptionally coupled IκBα/NF-κB negative feedback loop, a pivotal regulatory node of innate immunity and inflammation, represents a model system for multiscalar reporters. Using a κB(5)→IκBα-FLuc bioluminescent reporter, we rigorously evaluated the dynamics of ΙκBα degradation and subsequent NF-κB transcriptional activity in response to diverse modes of TNFα stimulation. Modulating TNFα concentration or pulse duration yielded complex, reproducible, and differential ΙκBα dynamics in both cell populations and live single cells. Tremendous heterogeneity in the transcriptional amplitudes of individual responding cells was observed, which was greater than the heterogeneity in the transcriptional kinetics of responsive cells. Furthermore, administration of various TNFα doses in vivo generated ΙκBα dynamic profiles in the liver resembling those observed in single cells and populations of cells stimulated with TNFα pulses. This suggested that dose modulation of circulating TNFα was perceived by hepatocytes in vivo as pulses of increasing duration. Thus, a robust bioluminescent reporter strategy enabled rigorous quantitation of NF-κB/ΙκBα dynamics in both live single cells and cell populations and furthermore, revealed reproducible behaviors that informed interpretation of in vivo studies.