WorldWideScience

Sample records for guard rings based

  1. Minimizing guard ring dead space in silicon detectors with an n-type guard ring at the edge of the detector

    International Nuclear Information System (INIS)

    Palviainen, Tanja; Tuuva, Tuure; Leinonen, Kari

    2007-01-01

    Detectors with n-type silicon with an n + -type guard ring were investigated. In the present work, a new p + /n/n + detector structure with an n + guard ring is described. The guard ring is placed at the edge of the detector. The detector depletion region extends also sideways, allowing for signal collection very close to the n-guard ring. In this kind of detector structure, the dead space of the detector is minimized to be only below the guard ring. This is proved by simulations done using Silvaco/ATLAS software

  2. Minimizing guard ring dead space in silicon detectors with an n-type guard ring at the edge of the detector

    Energy Technology Data Exchange (ETDEWEB)

    Palviainen, Tanja [Lappeenranta University of Technology, P.O. Box 20, FIN-53851 Lappeenranta (Finland)]. E-mail: tanja.palviainen@lut.fi; Tuuva, Tuure [Lappeenranta University of Technology, P.O. Box 20, FIN-53851 Lappeenranta (Finland); Leinonen, Kari [Lappeenranta University of Technology, P.O. Box 20, FIN-53851 Lappeenranta (Finland)

    2007-04-01

    Detectors with n-type silicon with an n{sup +}-type guard ring were investigated. In the present work, a new p{sup +}/n/n{sup +} detector structure with an n{sup +} guard ring is described. The guard ring is placed at the edge of the detector. The detector depletion region extends also sideways, allowing for signal collection very close to the n-guard ring. In this kind of detector structure, the dead space of the detector is minimized to be only below the guard ring. This is proved by simulations done using Silvaco/ATLAS software.

  3. Comparison of electrical performances of two n-in-p detectors with different implant type of guard ring by TCAD simulation

    Directory of Open Access Journals (Sweden)

    Mohammed Mekheldi

    Full Text Available This paper presents a preliminary comparative study for two different guard rings structures in the purpose of evaluating their electrical performances. The two structures are based on the n-in-p technology with different implant type of guard rings. I–V characteristics have been simulated using Silvaco/ATLAS software for both structures and compared for various parameters of substrate, guard ring and oxide. Simulation results show that the shape of leakage current is almost the same in all simulations but in terms of breakdown voltage, n-in-p structure with n-type guard rings ensures high voltage stability. Keywords: Breakdown voltage, Guard ring, n-in-p silicon detector, TCAD simulation

  4. Role of guard rings in improving the performance of silicon detectors

    Indian Academy of Sciences (India)

    number of free charge carriers thus produced is proportional to the energy deposited. 259 .... grounding the innermost guard ring of a strip detector of geometry 60 × 60 mm2. ... The guard ring was kept floating with no electrical connection .... ment of maintaining high-quality semiconductor properties during high temperature.

  5. Comparison of electrical performances of two n-in-p detectors with different implant type of guard ring by TCAD simulation

    Science.gov (United States)

    Mekheldi, Mohammed; Oussalah, Slimane; Lounis, Abdenour; Brihi, Nourredine

    This paper presents a preliminary comparative study for two different guard rings structures in the purpose of evaluating their electrical performances. The two structures are based on the n-in-p technology with different implant type of guard rings. I-V characteristics have been simulated using Silvaco/ATLAS software for both structures and compared for various parameters of substrate, guard ring and oxide. Simulation results show that the shape of leakage current is almost the same in all simulations but in terms of breakdown voltage, n-in-p structure with n-type guard rings ensures high voltage stability.

  6. Modeling and Design Guidelines for P⁺ Guard Rings in Lightly Doped CMOS Substrates

    DEFF Research Database (Denmark)

    Shen, Ming; Mikkelsen, Jan H.; Zhang, Ke

    2013-01-01

    of ${rm P}^{+}$ guard rings in terms of S-parameters, which is useful for substrate noise mitigation in mixed-signal system-on-chips. Validation of the model has been done by both electromagnetic simulation and experimental results from guard rings implemented using a standard 0.18-$mu{rm m}$ CMOS process....... In addition, design guidelines have been drawn for minimizing the guard ring size while maintaining the noise suppression performance....

  7. Electrical crosstalk in front-illuminated photodiode array with different guard ring designs for medical CT applications

    International Nuclear Information System (INIS)

    Ji Fan; Juntunen, Mikko; Hietanen, Iiro

    2009-01-01

    This paper presents electrical crosstalk studies on front-illuminated photodiode arrays for medical computed tomography (CT) applications. Crosstalk is an important factor to the system noise and image quality. The electrical crosstalk depends on silicon substrate properties and photodiode structures. The photodiode samples employed in this paper are planar processed on high-resistivity n-type silicon substrate, resulting in a p+/n-/n+ diode structure. Two types of guard ring structures are designed and applied to the same geometry of two-dimensional photodiode arrays. One structure is an n guard ring in the gap area between pixels, and the other structure is an additional p+ guard ring around each pixel together with the n guard ring. A 10 μm light spot with wavelength of 525 nm is used to scan across the surface of the photodiode array in the electrical crosstalk measurements. The electrical currents of two neighbor pixels are measured and the results are compared between two guard ring designs. The design with the p+ guard ring structure gives better electrical crosstalk suppression. Moreover, the measurement results show much smaller influence on surrounding pixels with the p+ guard ring structure in the case of disconnected pixel. Besides the electrical crosstalk, the light sensitivity within the gap area is also discussed between two guard ring designs.

  8. Role of guard rings in improving the performance of silicon detectors

    Indian Academy of Sciences (India)

    the microelectronics industry, its material properties and processing techniques ... varied shapes and sizes using standard IC fabrication technology to suit specific ... Figure 1. (a) Fabricated 4 wafer showing strip detector of area 6.3 × 6.3 ... all the experimental conditions the same and the guard ring was biased at ground.

  9. A novel stress isolation guard-ring design for the improvement of a three-axis piezoresistive accelerometer

    International Nuclear Information System (INIS)

    Hsieh, Hsieh-Shen; Chang, Heng-Chung; Hu, Chih-Fan; Cheng, Chao-Lin; Fang, Weileun

    2011-01-01

    This study designs and implements a stress isolation guard-ring structure to improve the performances of the existing single proof-mass three-axis piezoresistive accelerometer. Thus, the environment disturbances, such as temperature variation and force/deflection transmittance, for a packaged three-axis piezoresistive accelerometer are significantly reduced. In application, the three-axis piezoresistive accelerometer has been fabricated using the bulk micromachining process on the SOI wafer. Experimental results show that the out-of-plane deformation of the suspended spring mass on the packaged accelerometer is reduced from 0.72 to 0.10 µm at a 150 °C temperature elevation. The temperature coefficient of zero-g offset for the presented sensor is reduced, and the temperature-induced sensitivity variation is minimized as well. Measurements also demonstrate that the guard-ring design successfully reduces the false signals induced by the force and displacement transmittance disturbances for one order of magnitude. Moreover, the three-axis acceleration sensing for the presented accelerometer with guard ring has also been demonstrated with sensitivities of 0.12–0.17 mV V −1 g −1 and nonlinearity < 1.02%.

  10. Study of 4H-SiC junction barrier Schottky diode using field guard ring termination

    International Nuclear Information System (INIS)

    Feng-Ping, Chen; Yu-Ming, Zhang; Hong-Liang, Lü; Yi-Men, Zhang; Jian-Hua, Huang

    2010-01-01

    This paper reports that the 4H-SiC Schottky barrier diode, PiN diode and junction barrier Schottky diode terminated by field guard rings are designed, fabricated and characterised. The measurements for forward and reverse characteristics have been done, and by comparison with each other, it shows that junction barrier Schottky diode has a lower reverse current density than that of the Schottky barrier diode and a higher forward drop than that of the PiN diode. High-temperature annealing is presented in this paper as well to figure out an optimised processing. The barrier height of 0.79 eV is formed with Ti in this work, the forward drop for the Schottky diode is 2.1 V, with an ideality factor of 3.2, and junction barrier Schottky diode with blocking voltage higher than 400 V was achieved by using field guard ring termination. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  11. Design, fabrication and characterization of multi-guard-ring furnished p+n-n+ silicon strip detectors for future HEP experiments

    Science.gov (United States)

    Lalwani, Kavita; Jain, Geetika; Dalal, Ranjeet; Ranjan, Kirti; Bhardwaj, Ashutosh

    2016-07-01

    Si detectors, in various configurations (strips and pixels), have been playing a key role in High Energy Physics (HEP) experiments due to their excellent vertexing and high precision tracking information. In future HEP experiments like upgrade of the Compact Muon Solenoid experiment (CMS) at the Large Hadron Collider (LHC), CERN and the proposed International Linear Collider (ILC), the Si tracking detectors will be operated in a very harsh radiation environment, which leads to both surface and bulk damage in Si detectors which in turn changes their electrical properties, i.e. change in the full depletion voltage, increase in the leakage current and decrease in the charge collection efficiency. In order to achieve the long term durability of Si-detectors in future HEP experiments, it is required to operate these detectors at very high reverse biases, beyond the full depletion voltage, thus requiring higher detector breakdown voltage. Delhi University (DU) is involved in the design, fabrication and characterization of multi-guard-ring furnished ac-coupled, single sided, p+n-n+ Si strip detectors for future HEP experiments. The design has been optimized using a two-dimensional numerical device simulation program (TCAD-Silvaco). The Si strip detectors are fabricated with eight-layers mask process using the planar fabrication technology by Bharat Electronic Lab (BEL), India. Further an electrical characterization set-up is established at DU to ensure the quality performance of fabricated Si strip detectors and test structures. In this work measurement results on non irradiated Si Strip detectors and test structures with multi-guard-rings using Current Voltage (IV) and Capacitance Voltage (CV) characterization set-ups are discussed. The effect of various design parameters, for example guard-ring spacing, number of guard-rings and metal overhang on breakdown voltage of test structures have been studied.

  12. Electric Characteristic Enhancement of an AZO/Si Schottky Barrier Diode with Hydrogen Plasma Surface Treatment and AlxOx Guard Ring Structure

    Directory of Open Access Journals (Sweden)

    Chien-Yu Li

    2018-01-01

    Full Text Available In this study, the design and fabrication of AZO/n-Si Schottky barrier diodes (SBDs with hydrogen plasma treatment on silicon surface and AlxOx guard ring were presented. The Si surface exhibited less interface defects after the cleaning process following with 30 w of H2 plasma treatment that improved the switching properties of the following formed SBDs. The rapid thermal annealing experiment also held at 400 °C to enhance the breakdown voltage of SBDs. The edge effect of the SBDs was also suppressed with the AlxOx guard ring structure deposited by the atomic layer deposition (ALD at the side of the SBDs. Experimental results show that the reverse leakage current was reduced and the breakdown voltage increased with an addition of the AlxOx guard ring. The diode and fabrication technology developed in the study were applicable to the realization of SBDs with a high breakdown voltage (>200 V, a low reverse leakage current density (≤72 μA/mm2@100 V, and a Schottky barrier height of 1.074 eV.

  13. Electric Characteristic Enhancement of an AZO/Si Schottky Barrier Diode with Hydrogen Plasma Surface Treatment and AlxOx Guard Ring Structure

    Science.gov (United States)

    Li, Chien-Yu; Cheng, Min-Yu; Houng, Mau-Phon; Yang, Cheng-Fu; Liu, Jing

    2018-01-01

    In this study, the design and fabrication of AZO/n-Si Schottky barrier diodes (SBDs) with hydrogen plasma treatment on silicon surface and AlxOx guard ring were presented. The Si surface exhibited less interface defects after the cleaning process following with 30 w of H2 plasma treatment that improved the switching properties of the following formed SBDs. The rapid thermal annealing experiment also held at 400 °C to enhance the breakdown voltage of SBDs. The edge effect of the SBDs was also suppressed with the AlxOx guard ring structure deposited by the atomic layer deposition (ALD) at the side of the SBDs. Experimental results show that the reverse leakage current was reduced and the breakdown voltage increased with an addition of the AlxOx guard ring. The diode and fabrication technology developed in the study were applicable to the realization of SBDs with a high breakdown voltage (>200 V), a low reverse leakage current density (≤72 μA/mm2@100 V), and a Schottky barrier height of 1.074 eV. PMID:29316726

  14. 78 FR 11676 - Notice of Inventory Completion: National Guard Bureau/A7AN, Air National Guard, Joint Base...

    Science.gov (United States)

    2013-02-19

    ... Inventory Completion: National Guard Bureau/A7AN, Air National Guard, Joint Base Andrews, MD AGENCY..., Joint Base Andrews, MD, has completed an inventory of human remains and associated funerary objects, in... associated funerary objects may contact National Guard Bureau, Air National Guard, Joint Base Andrews, MD...

  15. Determination of corrosion rate of reinforcement with a modulated guard ring electrode; analysis of errors due to lateral current distribution

    International Nuclear Information System (INIS)

    Wojtas, H.

    2004-01-01

    The main source of errors in measuring the corrosion rate of rebars on site is a non-uniform current distribution between the small counter electrode (CE) on the concrete surface and the large rebar network. Guard ring electrodes (GEs) are used in an attempt to confine the excitation current within a defined area. In order to better understand the functioning of modulated guard ring electrode and to assess its effectiveness in eliminating errors due to lateral spread of current signal from the small CE, measurements of the polarisation resistance performed on a concrete beam have been numerically simulated. Effect of parameters such as rebar corrosion activity, concrete resistivity, concrete cover depth and size of the corroding area on errors in the estimation of polarisation resistance of a single rebar has been examined. The results indicate that modulated GE arrangement fails to confine the lateral spread of the CE current within a constant area. Using the constant diameter of confinement for the calculation of corrosion rate may lead to serious errors when test conditions change. When high corrosion activity of rebar and/or local corrosion occur, the use of the modulated GE confinement may lead to significant underestimation of the corrosion rate

  16. Room-temperature particle detectors with guard rings based on semi-insulating InP co-doped with Ti and Zn

    International Nuclear Information System (INIS)

    Yatskiv, R.; Zdansky, K.; Pekarek, L.

    2009-01-01

    Particle detectors made with a guard-ring (GR) electrode, operating at room temperature, have been studied. The detectors were fabricated on a semi-insulating InP crystal co-doped with Ti and Zn, grown using the Liquid-Encapsulated Czochralski technique. The detection performance of the particle detectors was evaluated using alpha particles emitted from a 241 Am source. Good detector performance has been achieved with measured charge-collection efficiencies of 99.9% and 98.2% and FWHM energy resolutions of 0.9% and 2.1%. The measurements were carried out at 230 K for negative and positive bias voltages of the irradiated electrode. The good performance is due to the SI properties of the material which has been achieved by doping with suitable Ti atoms and co-doping with a low concentration of Zn acceptors, sufficient to fully compensate shallow donors. Electron and hole charge-collection efficiencies (CCEs) were measured at various temperatures. At room temperature, unlike at low temperature (T<250 K), the hole CCE was better than the electron CCE, which can be explained by the presence of electron-trapping centres in InP with a temperature-dependent capture rate.

  17. 33 CFR 165.776 - Security Zone; Coast Guard Base San Juan, San Juan Harbor, Puerto Rico

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Security Zone; Coast Guard Base San Juan, San Juan Harbor, Puerto Rico 165.776 Section 165.776 Navigation and Navigable Waters COAST... Guard District § 165.776 Security Zone; Coast Guard Base San Juan, San Juan Harbor, Puerto Rico (a...

  18. Guard News - The National Guard

    Science.gov (United States)

    operations during chemical attack May 25, 2018 - SWANTON, Ohio - Maintenance is a critical component in Leaders discuss future of National Guard cyber warfare May 21, 2018 - CAMP ATTERBURY, Ind. - While National Guard teams from across the nation tested themselves on their cyber defensive capabilities at

  19. National Guard > About the Guard > Today in Guard History

    Science.gov (United States)

    National Guard About Us By the Numbers Contact Us FAQ Federal Mission History Join Us Leaders Director of Program Training & Technology Battle Lab (T3BL) Civil Support Simulation Exercises Regional Training March Today in Guard History Leadership CNGB VCNGB SEA DANG DARNG Joint Staff J-1 J-2 J-3 J-4 J-5 J-6 J

  20. Guarded Type Promotion

    DEFF Research Database (Denmark)

    Winther, Johnni

    2011-01-01

    conditional using the instanceof operator and thus the cast type is redundantly mentioned twice. We propose a new typing rule for Java called Guarded Type Promotion aimed at eliminating the need for the explicit casts when guarded. This new typing rule is backward compatible and has been fully implemented...... in a Java 6 compiler. Through our extensive testing of real-life code we show that guarded casts account for approximately one fourth of all casts and that Guarded Type Promotion can eliminate the need for 95 percent of these guarded casts....

  1. How We Began - About the Guard - The National Guard

    Science.gov (United States)

    Marshal Office of the Joint Surgeon PARC Small Business Programs Chaplain Diversity NGB-GOMO Resources Legislative Liaison Small Business Programs Social Media State Websites Videos Featured Videos On Every Front the organization date of the oldest Army National Guard units is based in law. The Militia Act of May

  2. The effectiveness of shin guards used by football players.

    Science.gov (United States)

    Tatar, Yasar; Ramazanoglu, Nusret; Camliguney, Asiye Filiz; Saygi, Evrim Karadag; Cotuk, Hasan Birol

    2014-01-01

    In football, injuries from opponent contact occur commonly in the lower extremities. FIFA the world's governing body for football requires players to wear shin guards. The aim of this study was to compare the protective effectiveness of polypropylene based shin guards with custom-made carbon fiber ones. Three commercial polypropylene shin guards (Adidas Predator™, Adidas UCL™, and Nike Mercurial™) and two custom-made carbon fiber shin guards were examined. The experimental setup had the following parts: 1) A pendulum attached a load cell at the tip (CAS Corp., Korea) and a fixed prosthetic foot equipped with a cleat to simulate an attacker's foot. 2) An artificial tibia prepared by condensed foam and reinforced by carbon fibers protected with soft clothing. 3) A multifunctional sensor system (Tekscan Corp., F-Socket System, Turkey) to record the impact on the tibia. In the low impact force trials, only 2.79-9.63 % of the load was transmitted to the sensors. When comparing for mean force, peak force and impulse, both carbon fiber shin guards performed better than the commercial ones (Adidas Predator™, Adidas UCL™, and Nike Mercurial™) (p = 0.000). Based on these same parameters, the Nike Mercurial™ provided better protection than the Adidas Predator™ and the Adidas UCL™ (p = 0.000). In the high impact force trials, only 5.16-10.90 % of the load was transmitted to the sensors. For peak force and impulse, the carbon fiber shin guards provided better protection than all the others. Carbon fiber shin guards possess protective qualities superior to those of commercial polypropylene shin guards. Key PointsShin guards decrease the risk of serious injuries.Carbon shin guards provide sufficient protection against high impact forces.Commercially available Polypropylene based shin guards do not provide sufficient protection against high impact forces.

  3. 33 CFR 149.321 - How many ring life buoys must be on each deepwater port?

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false How many ring life buoys must be on each deepwater port? 149.321 Section 149.321 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Lifesaving Equipment Manned Deepwater Port Requirements § 149.321 How many ring life buoys must be...

  4. Volunteers in the Danish Home Guard 2016

    DEFF Research Database (Denmark)

    Fridberg, Torben; Larsen, Mona

    This report maps the composition of a group of volunteer members of the Home Guard, as well as their opinions and expectations of the Home Guard and their own voluntary efforts. The report is a follow-up to two previous surveys completed in 2007 and 2011 and it therefore also highlights changes...... from 2007 to 2011 and 2016. Based on a questionnaire survey, the report paints a picture of who the volunteers are, what motivates them and how they perceive their surrounding environment’s view of them as members of the Home Guard. The report also focuses on the volunteers’ view of the Home Guard......’s tasks and activities both in Denmark and abroad. Finally, the report describes the volunteers’ perception of the Home Guards’ communication and campaigns. The report was commissioned and financed by the Danish Home Guard Command....

  5. Bird guard

    Science.gov (United States)

    Fairchild, Dana M [Armour, SD

    2010-03-02

    The bird guard provides a device to protect electrical insulators comprising a central shaft; a clamp attached to an end of the shaft to secure the device to a transmission tower; a top and bottom cover to shield transmission tower insulators; and bearings to allow the guard to rotate in order to frighten birds away from the insulators.

  6. Irrational Guards are Sometimes Needed

    DEFF Research Database (Denmark)

    Abrahamsen, Mikkel; Adamaszek, Anna; Miltzow, Tillmann

    2017-01-01

    In this paper we study the art gallery problem, which is one of the fundamental problems in computational geometry. The objective is to place a minimum number of guards inside a simple polygon so that the guards together can see the whole polygon. We say that a guard at position x sees a point y...... if the line segment xy is contained in the polygon. Despite an extensive study of the art gallery problem, it remained an open question whether there are polygons given by integer coordinates that require guard positions with irrational coordinates in any optimal solution. We give a positive answer...... to this question by constructing a monotone polygon with integer coordinates that can be guarded by three guards only when we allow to place the guards at points with irrational coordinates. Otherwise, four guards are needed. By extending this example, we show that for every n, there is a polygon which can...

  7. Coast Guard

    International Nuclear Information System (INIS)

    1991-09-01

    The 11-million gallon Exxon Valdez oil spill highlighted deficiencies in the nation's ability to contain and recover spilled oil. The Oil Pollution Act of 1990 represents a major effort by Congress to address these deficiencies and to clarify the roles and responsibilities of the private sector and the federal government in preventing, preparing for, and responding to oil spills. This report examines the Coast Guard's efforts to avoid unnecessary and wasteful duplication by coordinating with the private sector and others, including federal and state agencies, its plans to buy oil spill response equipment and the new responsibilities the act places on the private sector and the Coast Guard and if these responsibilities call for a shift in emphasis in Coast Guard oil spill response activities

  8. Chemical Sensors Based on Optical Ring Resonators

    Science.gov (United States)

    Homer, Margie; Manfreda, Allison; Mansour, Kamjou; Lin, Ying; Ksendzov, Alexander

    2005-01-01

    Chemical sensors based on optical ring resonators are undergoing development. A ring resonator according to this concept is a closed-circuit dielectric optical waveguide. The outermost layer of this waveguide, analogous to the optical cladding layer on an optical fiber, is a made of a polymer that (1) has an index of refraction lower than that of the waveguide core and (2) absorbs chemicals from the surrounding air. The index of refraction of the polymer changes with the concentration of absorbed chemical( s). The resonator is designed to operate with relatively strong evanescent-wave coupling between the outer polymer layer and the electromagnetic field propagating along the waveguide core. By virtue of this coupling, the chemically induced change in index of refraction of the polymer causes a measurable shift in the resonance peaks of the ring. In a prototype that has been used to demonstrate the feasibility of this sensor concept, the ring resonator is a dielectric optical waveguide laid out along a closed path resembling a racetrack (see Figure 1). The prototype was fabricated on a silicon substrate by use of standard techniques of thermal oxidation, chemical vapor deposition, photolithography, etching, and spin coating. The prototype resonator waveguide features an inner cladding of SiO2, a core of SixNy, and a chemical-sensing outer cladding of ethyl cellulose. In addition to the ring Chemical sensors based on optical ring resonators are undergoing development. A ring resonator according to this concept is a closed-circuit dielectric optical waveguide. The outermost layer of this waveguide, analogous to the optical cladding layer on an optical fiber, is a made of a polymer that (1) has an index of refraction lower than that of the waveguide core and (2) absorbs chemicals from the surrounding air. The index of refraction of the polymer changes with the concentration of absorbed chemical( s). The resonator is designed to operate with relatively strong

  9. Guarded Cubical Type Theory

    DEFF Research Database (Denmark)

    Birkedal, Lars; Bizjak, Aleš; Clouston, Ranald

    2016-01-01

    This paper improves the treatment of equality in guarded dependent type theory (GDTT), by combining it with cubical type theory (CTT). GDTT is an extensional type theory with guarded recursive types, which are useful for building models of program logics, and for programming and reasoning...... with coinductive types. We wish to implement GDTT with decidable type-checking, while still supporting non-trivial equality proofs that reason about the extensions of guarded recursive constructions. CTT is a variation of Martin-L\\"of type theory in which the identity type is replaced by abstract paths between...... terms. CTT provides a computational interpretation of functional extensionality, is conjectured to have decidable type checking, and has an implemented type-checker. Our new type theory, called guarded cubical type theory, provides a computational interpretation of extensionality for guarded recursive...

  10. Powder metallurgy ferrous synchronizer ring with brass-based friction layer; Tetsu-do niso shoketsu synchronize ring no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Okajima, H; Yoshikawa, K; Miyajima, K; Sugiyama, M [Toyota Motor Corp., Aichi (Japan); Nakamura, M; Ito, M [Japan Powder Metallurgy Co. Ltd., Tokyo (Japan)

    1997-10-01

    Synchronizer rings for manual transmissions are generally made of brass or molybdenum coated brass. Powder metallurgy (PM) synchronizer ring was developed for the purpose of high performance and cost reduction. This synchronizer ring consists of the high strength PM ferrous ring that needs neither special densification nor heat treatment, and it has the brass-based friction layer. New joining technique was required because of that shape and two different materials. Powder of copper-phosphorus alloy are admixed with the friction material. While sintering, that melt and migrate to the interface. Then the friction layer and the ferrous ring are joined tightly. 7 refs., 9 figs., 6 tabs.

  11. The Effectiveness of Shin Guards Used by Football Players

    Directory of Open Access Journals (Sweden)

    Yasar Tatar

    2013-03-01

    Full Text Available In football, injuries from opponent contact occur commonly in the lower extremities. FIFA the world’s governing body for football requires players to wear shin guards. The aim of this study was to compare the protective effectiveness of polypropylene based shin guards with custom-made carbon fiber ones. Three commercial polypropylene shin guards (Adidas Predator™, Adidas UCL™, and Nike Mercurial™ and two custom-made carbon fiber shin guards were examined. The experimental setup had the following parts: 1 A pendulum attached a load cell at the tip (CAS Corp., Korea and a fixed prosthetic foot equipped with a cleat to simulate an attacker’s foot. 2 An artificial tibia prepared by condensed foam and reinforced by carbon fibers protected with soft clothing. 3 A multifunctional sensor system (Tekscan Corp., F-Socket System, Turkey to record the impact on the tibia. In the low impact force trials, only 2.79-9.63 % of the load was transmitted to the sensors. When comparing for mean force, peak force and impulse, both carbon fiber shin guards performed better than the commercial ones (Adidas Predator™, Adidas UCL™, and Nike Mercurial™ (p = 0.000. Based on these same parameters, the Nike Mercurial™ provided better protection than the Adidas Predator™ and the Adidas UCL™ (p = 0.000. In the high impact force trials, only 5.16-10.90 % of the load was transmitted to the sensors. For peak force and impulse, the carbon fiber shin guards provided better protection than all the others. Carbon fiber shin guards possess protective qualities superior to those of commercial polypropylene shin guards.

  12. Exploring emergent properties in cellular homeostasis using OnGuard to model K+ and other ion transport in guard cells.

    Science.gov (United States)

    Blatt, Michael R; Wang, Yizhou; Leonhardt, Nathalie; Hills, Adrian

    2014-05-15

    It is widely recognized that the nature and characteristics of transport across eukaryotic membranes are so complex as to defy intuitive understanding. In these circumstances, quantitative mathematical modeling is an essential tool, both to integrate detailed knowledge of individual transporters and to extract the properties emergent from their interactions. As the first, fully integrated and quantitative modeling environment for the study of ion transport dynamics in a plant cell, OnGuard offers a unique tool for exploring homeostatic properties emerging from the interactions of ion transport, both at the plasma membrane and tonoplast in the guard cell. OnGuard has already yielded detail sufficient to guide phenotypic and mutational studies, and it represents a key step toward 'reverse engineering' of stomatal guard cell physiology, based on rational design and testing in simulation, to improve water use efficiency and carbon assimilation. Its construction from the HoTSig libraries enables translation of the software to other cell types, including growing root hairs and pollen. The problems inherent to transport are nonetheless challenging, and are compounded for those unfamiliar with conceptual 'mindset' of the modeler. Here we set out guidelines for the use of OnGuard and outline a standardized approach that will enable users to advance quickly to its application both in the classroom and laboratory. We also highlight the uncanny and emergent property of OnGuard models to reproduce the 'communication' evident between the plasma membrane and tonoplast of the guard cell. Copyright © 2014 The Authors. Published by Elsevier GmbH.. All rights reserved.

  13. Guarded dependent type theory with coinductive types

    DEFF Research Database (Denmark)

    Bizjak, Aleš; Grathwohl, Hans Bugge; Clouston, Ranald

    2016-01-01

    We present guarded dependent type theory, gDTT, an extensional dependent type theory with a later' modality and clock quantifiers for programming and proving with guarded recursive and coinductive types. The later modality is used to ensure the productivity of recursive definitions in a modular......, type based, way. Clock quantifiers are used for controlled elimination of the later modality and for encoding coinductive types using guarded recursive types. Key to the development of gDTT are novel type and term formers involving what we call delayed substitutions’. These generalise the applicative...... functor rules for the later modality considered in earlier work, and are crucial for programming and proving with dependent types. We show soundness of the type theory with respect to a denotational model....

  14. Coast Guard Proceedings. Volume 70, Number 2, Summer 2013

    Science.gov (United States)

    2013-01-01

    and well-being. Most Inuit are coastal people who rely heavily on resources from the ocean for nutritional and cultural survival. The Inuit are a...defend a soccer ball from a crewmember of the Russian vessel Vorovsky at the Coast Guard gym at Base Kodiak, Alaska. U.S. Coast Guard photo by

  15. Coast Guard Compass

    Science.gov (United States)

    looks on as Adm. Charles Ray thanks Adm. Chuck Michel for his service as the 30th vice commandant of the commandant Adm. Charles W. Ray relieved Adm. Charles D. Michel as vice commandant of the U.S. Coast Guard by . Following graduation and commissioning as an officer in the Coast Guard, Wright will be heading to the

  16. Future Synchrotron Light Sources Based on Ultimate Storage Rings

    International Nuclear Information System (INIS)

    Cai, Yunhai

    2012-01-01

    The main purpose of this talk is to describe how far one might push the state of the art in storage ring design. The talk will start with an overview of the latest developments and advances in the design of synchrotron light sources based on the concept of an 'ultimate' storage ring. The review will establish how bright a ring based light source might be, where the frontier of technological challenges are, and what the limits of accelerator physics are. Emphasis will be given to possible improvements in accelerator design and developments in technology toward the goal of achieving an ultimate storage ring. An ultimate storage ring (USR), defined as an electron ring-based light source having an emittance in both transverse planes at the diffraction limit for the range of X-ray wavelengths of interest for a scientific community, would provide very high brightness photons having high transverse coherence that would extend the capabilities of X-ray imaging and probe techniques beyond today's performance. It would be a cost-effective, high-coherence 4th generation light source, competitive with one based on energy recovery linac (ERL) technology, serving a large number of users studying material, chemical, and biological sciences. Furthermore, because of the experience accumulated over many decades of ring operation, it would have the great advantage of stability and reliability. In this paper we consider the design of an USR having 10-pm-rad emittance. It is a tremendous challenge to design a storage ring having such an extremely low emittance, a factor of 100 smaller than those in existing light sources, especially such that it has adequate dynamic aperture and beam lifetime. In many ultra-low emittance designs, the injection acceptances are not large enough for accumulation of the electron beam, necessitating on-axis injection where stored electron bunches are completely replaced with newly injected ones. Recently, starting with the MAX-IV 7-bend achromatic cell, we

  17. Future Synchrotron Light Sources Based on Ultimate Storage Rings

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yunhai; /SLAC

    2012-04-09

    The main purpose of this talk is to describe how far one might push the state of the art in storage ring design. The talk will start with an overview of the latest developments and advances in the design of synchrotron light sources based on the concept of an 'ultimate' storage ring. The review will establish how bright a ring based light source might be, where the frontier of technological challenges are, and what the limits of accelerator physics are. Emphasis will be given to possible improvements in accelerator design and developments in technology toward the goal of achieving an ultimate storage ring. An ultimate storage ring (USR), defined as an electron ring-based light source having an emittance in both transverse planes at the diffraction limit for the range of X-ray wavelengths of interest for a scientific community, would provide very high brightness photons having high transverse coherence that would extend the capabilities of X-ray imaging and probe techniques beyond today's performance. It would be a cost-effective, high-coherence 4th generation light source, competitive with one based on energy recovery linac (ERL) technology, serving a large number of users studying material, chemical, and biological sciences. Furthermore, because of the experience accumulated over many decades of ring operation, it would have the great advantage of stability and reliability. In this paper we consider the design of an USR having 10-pm-rad emittance. It is a tremendous challenge to design a storage ring having such an extremely low emittance, a factor of 100 smaller than those in existing light sources, especially such that it has adequate dynamic aperture and beam lifetime. In many ultra-low emittance designs, the injection acceptances are not large enough for accumulation of the electron beam, necessitating on-axis injection where stored electron bunches are completely replaced with newly injected ones. Recently, starting with the MAX-IV 7-bend

  18. Guarded Cubical Type Theory

    DEFF Research Database (Denmark)

    Birkedal, Lars; Bizjak, Aleš; Clouston, Ranald

    2016-01-01

    This paper improves the treatment of equality in guarded dependent type theory (GDTT), by combining it with cubical type theory (CTT). GDTT is an extensional type theory with guarded recursive types, which are useful for building models of program logics, and for programming and reasoning...... with coinductive types. We wish to implement GDTT with decidable type checking, while still supporting non-trivial equality proofs that reason about the extensions of guarded recursive constructions. CTT is a variation of Martin-L\\"of type theory in which the identity type is replaced by abstract paths between...... terms. CTT provides a computational interpretation of functional extensionality, enjoys canonicity for the natural numbers type, and is conjectured to support decidable type-checking. Our new type theory, guarded cubical type theory (GCTT), provides a computational interpretation of extensionality...

  19. Top-down fabrication of vertical silicon nano-rings based on Poisson diffraction

    International Nuclear Information System (INIS)

    Ai Yujie; Huang Ru; Hao Zhihua; Wang Runsheng; Liu Changze; Fan Chunhui; Wang Yangyuan

    2011-01-01

    Vertical Si nano-rings with a uniform thickness of about 100 nm have been fabricated by conventional optical photolithography with a low cost based on Poisson diffraction. Moreover, the roughness of the Si nano-rings can be effectively reduced by sacrificial oxidation. In order to increase the density of the nano-rings, coaxial twin Si nano-rings have been fabricated by the Poisson diffraction method combined with the spacer technique. The thickness of both the inner and outer Si nano-rings is about 60 nm, and the gap between the twin nano-rings is about 100 nm.

  20. Truck side guard specifications : recommended standard

    Science.gov (United States)

    2016-09-01

    This document is intended to be used by (1) public or private medium/heavy-duty truck fleets considering adding side guards; (2) jurisdictions or customers that require side guards through policy or procurement; (3) manufacturers of side guards; and ...

  1. Armed guards on vessels : insurance and liability

    Directory of Open Access Journals (Sweden)

    Mišo Mudrić

    2011-12-01

    Full Text Available The Paper examines the insurance and liability issues resulting from the use of armed guards on board vessels. The study begins with an overview of the available data on key economic fi gures representing the projected overall annual costs of modern piracy. The focus is then shifted to the issue of public versus private security, where possible dangers of private-based security options are discussed in general. After explaining why the Somalia region deserves a closer attention when compared to other pirate-infested waters, a brief summary of the international effort to combat piracy threat is presented, followed by a structured overview of the use of private maritime security options in the maritime sector in general. One security option is the use of armed guards on board vessels. This option is explored both from the political (the acceptance by stakeholders and legal standpoint (legal issues arising from the use of armed guards. An important remedy for the shipping companies/ operators threatened by the piracy hazard is the existence of affordable and effective (specialized marine insurance. A study of available piracy insurance policies is presented, followed by an analysis of case law and other legal issues arising from piracy attacks, which could prove important when considering the legal implications of armed guards employment. Finally, a simplifi ed economic analysis of available security options is presented, followed by the final assessment of benefi ts derived from the use of armed guards.

  2. Videos - The National Guard

    Science.gov (United States)

    Legislative Liaison Small Business Programs Social Media State Websites Videos Featured Videos On Every Front 2:17 Always Ready, Always There National Guard Bureau Diversity and Inclusion Play Button 1:04 National Guard Bureau Diversity and Inclusion The ChalleNGe Ep.5 [Graduation] Play Button 3:51 The

  3. 30 CFR 75.1722 - Mechanical equipment guards.

    Science.gov (United States)

    2010-07-01

    ... may cause injury to persons shall be guarded. (b) Guards at conveyor-drive, conveyor-head, and conveyor-tail pulleys shall extend a distance sufficient to prevent a person from reaching behind the guard and becoming caught between the belt and the pulley. (c) Except when testing the machinery, guards...

  4. 30 CFR 77.400 - Mechanical equipment guards.

    Science.gov (United States)

    2010-07-01

    ... shall be guarded. (b) Overhead belts shall be guarded if the whipping action from a broken line would be hazardous to persons below. (c) Guards at conveyor-drive, conveyor-head, and conveyor-tail pulleys shall... between the belt and the pulley. (d) Except when testing the machinery, guards shall be securely in place...

  5. An optimal guarding scheme for thermal conductivity measurement using a guarded cut-bar technique, part 1 experimental study

    International Nuclear Information System (INIS)

    Xing, Changhu

    2014-01-01

    In the guarded cut-bar technique, a guard surrounding the measured sample and reference (meter) bars is temperature controlled to carefully regulate heat losses from the sample and reference bars. Guarding is typically carried out by matching the temperature profiles between the guard and the test stack of sample and meter bars. Problems arise in matching the profiles, especially when the thermal conductivities of the meter bars and of the sample differ, as is usually the case. In a previous numerical study, the applied guarding condition (guard temperature profile) was found to be an important factor in measurement accuracy. Different from the linear-matched or isothermal schemes recommended in literature, the optimal guarding condition is dependent on the system geometry and thermal conductivity ratio of sample to meter bar. To validate the numerical results, an experimental study was performed to investigate the resulting error under different guarding conditions using stainless steel 304 as both the sample and meter bars. The optimal guarding condition was further verified on a certified reference material, pyroceram 9606, and 99.95% pure iron whose thermal conductivities are much smaller and much larger, respectively, than that of the stainless steel meter bars. Additionally, measurements are performed using three different inert gases to show the effect of the insulation effective thermal conductivity on measurement error, revealing low conductivity, argon gas, gives the lowest error sensitivity when deviating from the optimal condition. The result of this study provides a general guideline for the specific measurement method and for methods requiring optimal guarding or insulation

  6. Directory - Social Media - The National Guard

    Science.gov (United States)

    Brigade 1st Battalion, 145th Armored Regiment Headquarters and Headquarters Company, 1st Battalion, 145th Florida Air National Guard Florida Guard History Camp Blanding Joint Training Center Wolfpack Company, 1st Force Georgia National Guard Joint Force Headquarters 116th Air Control Wing Flickr Georgia National

  7. 33 CFR 23.10 - Coast Guard emblem.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Coast Guard emblem. 23.10 Section... DISTINCTIVE MARKINGS FOR COAST GUARD VESSELS AND AIRCRAFT § 23.10 Coast Guard emblem. (a) The distinctive emblem of the Coast Guard shall be as follows: On a disc the shield of the Coat of Arms of the United...

  8. Report of the eRHIC Ring-Ring Working Group

    Energy Technology Data Exchange (ETDEWEB)

    Aschenauer, E. C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brennan, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fedotov, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Litvinenko, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Montag, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Palmer, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Parker, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Peggs, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ranjbar, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tepikian, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trbojevic, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Willeke, F. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-10-13

    This report evaluates the ring-ring option for eRHIC as a lower risk alternative to the linac-ring option. The reduced risk goes along with a reduced initial luminosity performance. However, a luminosity upgrade path is kept open. This upgrade path consists of two branches, with the ultimate upgrade being either a ring-ring or a linac-ring scheme. The linac-ring upgrade could be almost identical to the proposed linac-ring scheme, which is based on an ERL in the RHIC tunnel. This linac-ring version has been studied in great detail over the past ten years, and its significant risks are known. On the other hand, no detailed work on an ultimate performance ring-ring scenario has been performed yet, other than the development of a consistent parameter set. Pursuing the ring-ring upgrade path introduces high risks and requires significant design work that is beyond the scope of this report.

  9. An Automatic Assembling System for Sealing Rings Based on Machine Vision

    Directory of Open Access Journals (Sweden)

    Mingyu Gao

    2017-01-01

    Full Text Available In order to grab and place the sealing rings of battery lid quickly and accurately, an automatic assembling system for sealing rings based on machine vision is developed in this paper. The whole system is composed of the light sources, cameras, industrial control units, and a 4-degree-of-freedom industrial robot. Specifically, the sealing rings are recognized and located automatically with the machine vision module. Then industrial robot is controlled for grabbing the sealing rings dynamically under the joint work of multiple control units and visual feedback. Furthermore, the coordinates of the fast-moving battery lid are tracked by the machine vision module. Finally the sealing rings are placed on the sealing ports of battery lid accurately and automatically. Experimental results demonstrate that the proposed system can grab the sealing rings and place them on the sealing port of the fast-moving battery lid successfully. More importantly, the proposed system can improve the efficiency of the battery production line obviously.

  10. Approximation algorithms for guarding holey polygons ...

    African Journals Online (AJOL)

    Guarding edges of polygons is a version of art gallery problem.The goal is finding the minimum number of guards to cover the edges of a polygon. This problem is NP-hard, and to our knowledge there are approximation algorithms just for simple polygons. In this paper we present two approximation algorithms for guarding ...

  11. Isolation of a strong Arabidopsis guard cell promoter and its potential as a research tool

    Science.gov (United States)

    Yang, Yingzhen; Costa, Alex; Leonhardt, Nathalie; Siegel, Robert S; Schroeder, Julian I

    2008-01-01

    Background A common limitation in guard cell signaling research is that it is difficult to obtain consistent high expression of transgenes of interest in Arabidopsis guard cells using known guard cell promoters or the constitutive 35S cauliflower mosaic virus promoter. An additional drawback of the 35S promoter is that ectopically expressing a gene throughout the organism could cause pleiotropic effects. To improve available methods for targeted gene expression in guard cells, we isolated strong guard cell promoter candidates based on new guard cell-specific microarray analyses of 23,000 genes that are made available together with this report. Results A promoter, pGC1(At1g22690), drove strong and relatively specific reporter gene expression in guard cells including GUS (beta-glucuronidase) and yellow cameleon YC3.60 (GFP-based calcium FRET reporter). Reporter gene expression was weaker in immature guard cells. The expression of YC3.60 was sufficiently strong to image intracellular Ca2+ dynamics in guard cells of intact plants and resolved spontaneous calcium transients in guard cells. The GC1 promoter also mediated strong reporter expression in clustered stomata in the stomatal development mutant too-many-mouths (tmm). Furthermore, the same promoter::reporter constructs also drove guard cell specific reporter expression in tobacco, illustrating the potential of this promoter as a method for high level expression in guard cells. A serial deletion of the promoter defined a guard cell expression promoter region. In addition, anti-sense repression using pGC1 was powerful for reducing specific GFP gene expression in guard cells while expression in leaf epidermal cells was not repressed, demonstrating strong cell-type preferential gene repression. Conclusion The pGC1 promoter described here drives strong reporter expression in guard cells of Arabidopsis and tobacco plants. It provides a potent research tool for targeted guard cell expression or gene silencing. It is also

  12. Petrographic Analysis of Portland Cement Concrete Cores from Pease Air National Guard Base, New Hampshire

    Science.gov (United States)

    2016-11-01

    Petrographic Analysis of Portland Cement Concrete Cores from Pease Air National Guard Base, New Hampshire E n g in e e r R e s e a rc h a n d...id, age of the concrete being evaluated and tests performed...4 3 Preface This study was conducted in support of the Air Force Civil Engineer Center (AFCEC) to assess concrete obtained from Pease

  13. Biomarkers and biometric measures of adherence to use of ARV-based vaginal rings.

    Science.gov (United States)

    Stalter, Randy M; Moench, Thomas R; MacQueen, Kathleen M; Tolley, Elizabeth E; Owen, Derek H

    2016-01-01

    Poor adherence to product use has been observed in recent trials of antiretroviral (ARV)-based oral and vaginal gel HIV prevention products, resulting in an inability to determine product efficacy. The delivery of microbicides through vaginal rings is widely perceived as a way to achieve better adherence but vaginal rings do not eliminate the adherence challenges exhibited in clinical trials. Improved objective measures of adherence are needed as new ARV-based vaginal ring products enter the clinical trial stage. To identify technologies that have potential future application for vaginal ring adherence measurement, a comprehensive literature search was conducted that covered a number of biomedical and public health databases, including PubMed, Embase, POPLINE and the Web of Science. Published patents and patent applications were also searched. Technical experts were also consulted to gather more information and help evaluate identified technologies. Approaches were evaluated as to feasibility of development and clinical trial implementation, cost and technical strength. Numerous approaches were identified through our landscape analysis and classified as either point measures or cumulative measures of vaginal ring adherence. Point measurements are those that give a measure of adherence at a particular point in time. Cumulative measures attempt to measure ring adherence over a period of time. Approaches that require modifications to an existing ring product are at a significant disadvantage, as this will likely introduce additional regulatory barriers to the development process and increase manufacturing costs. From the point of view of clinical trial implementation, desirable attributes would be high acceptance by trial participants, and little or no additional time or training requirements on the part of participants or clinic staff. We have identified four promising approaches as being high priority for further development based on the following measurements

  14. Isolation of a strong Arabidopsis guard cell promoter and its potential as a research tool

    Directory of Open Access Journals (Sweden)

    Siegel Robert S

    2008-02-01

    Full Text Available Abstract Background A common limitation in guard cell signaling research is that it is difficult to obtain consistent high expression of transgenes of interest in Arabidopsis guard cells using known guard cell promoters or the constitutive 35S cauliflower mosaic virus promoter. An additional drawback of the 35S promoter is that ectopically expressing a gene throughout the organism could cause pleiotropic effects. To improve available methods for targeted gene expression in guard cells, we isolated strong guard cell promoter candidates based on new guard cell-specific microarray analyses of 23,000 genes that are made available together with this report. Results A promoter, pGC1(At1g22690, drove strong and relatively specific reporter gene expression in guard cells including GUS (beta-glucuronidase and yellow cameleon YC3.60 (GFP-based calcium FRET reporter. Reporter gene expression was weaker in immature guard cells. The expression of YC3.60 was sufficiently strong to image intracellular Ca2+ dynamics in guard cells of intact plants and resolved spontaneous calcium transients in guard cells. The GC1 promoter also mediated strong reporter expression in clustered stomata in the stomatal development mutant too-many-mouths (tmm. Furthermore, the same promoter::reporter constructs also drove guard cell specific reporter expression in tobacco, illustrating the potential of this promoter as a method for high level expression in guard cells. A serial deletion of the promoter defined a guard cell expression promoter region. In addition, anti-sense repression using pGC1 was powerful for reducing specific GFP gene expression in guard cells while expression in leaf epidermal cells was not repressed, demonstrating strong cell-type preferential gene repression. Conclusion The pGC1 promoter described here drives strong reporter expression in guard cells of Arabidopsis and tobacco plants. It provides a potent research tool for targeted guard cell expression or

  15. Optimizing ring-based CSR sources

    International Nuclear Information System (INIS)

    Byrd, J.M.; De Santis, S.; Hao, Z.; Martin, M.C.; Munson, D.V.; Li, D.; Nishimura, H.; Robin, D.S.; Sannibale, F.; Schlueter, R.D.; Schoenlein, R.; Jung, J.Y.; Venturini, M.; Wan, W.; Zholents, A.A.; Zolotorev, M.

    2004-01-01

    Coherent synchrotron radiation (CSR) is a fascinating phenomenon recently observed in electron storage rings and shows tremendous promise as a high power source of radiation at terahertz frequencies. However, because of the properties of the radiation and the electron beams needed to produce it, there are a number of interesting features of the storage ring that can be optimized for CSR. Furthermore, CSR has been observed in three distinct forms: as steady pulses from short bunches, bursts from growth of spontaneous modulations in high current bunches, and from micro modulations imposed on a bunch from laser slicing. These processes have their relative merits as sources and can be improved via the ring design. The terahertz (THz) and sub-THz region of the electromagnetic spectrum lies between the infrared and the microwave . This boundary region is beyond the normal reach of optical and electronic measurement techniques and sources associated with these better-known neighbors. Recent research has demonstrated a relatively high power source of THz radiation from electron storage rings: coherent synchrotron radiation (CSR). Besides offering high power, CSR enables broadband optical techniques to be extended to nearly the microwave region, and has inherently sub-picosecond pulses. As a result, new opportunities for scientific research and applications are enabled across a diverse array of disciplines: condensed matter physics, medicine, manufacturing, and space and defense industries. CSR will have a strong impact on THz imaging, spectroscopy, femtosecond dynamics, and driving novel non-linear processes. CSR is emitted by bunches of accelerated charged particles when the bunch length is shorter than the wavelength being emitted. When this criterion is met, all the particles emit in phase, and a single-cycle electromagnetic pulse results with an intensity proportional to the square of the number of particles in the bunch. It is this quadratic dependence that can

  16. DDH-Like Assumptions Based on Extension Rings

    DEFF Research Database (Denmark)

    Cramer, Ronald; Damgård, Ivan Bjerre; Kiltz, Eike

    2012-01-01

    We introduce and study a new type of DDH-like assumptions based on groups of prime order q. Whereas standard DDH is based on encoding elements of $\\mathbb{F}_{q}$ “in the exponent” of elements in the group, we ask what happens if instead we put in the exponent elements of the extension ring $R_f=......-Reingold style pseudorandom functions, and auxiliary input secure encryption. This can be seen as an alternative to the known family of k-LIN assumptions....

  17. Femtosecond laser-induced concentric ring microstructures on Zr-based metallic glass

    International Nuclear Information System (INIS)

    Ma Fengxu; Yang Jianjun; Xiaonong Zhu; Liang Chunyong; Wang Hongshui

    2010-01-01

    Surface morphological evolution of Zr-based metallic glass ablated by femtosecond lasers is investigated in atmosphere condition. Three types of permanent ring structures with micro-level spacing are observed for different laser shots and fluences. In the case of low laser fluences, the generation of annular patterns with nonthermal features is observed on the rippled structure with the subwavelength scale, and the ring spacing shows a decrease tendency from the center to the margin. While in the case of high laser fluences, the concentric rings formation within the laser spot is found to have evident molten traces and display the increasing ring spacing along the radial direction. Moreover, when the laser shots accumulation becomes large, the above two types of ring microstructures begin to develop into the common ablation craters. Analysis and discussion suggests that the stress-induced condensation of ablation vapors and the frozen thermocapillary waves on the molten surfaces should be responsible for the formation of two different types of concentric ring structures, respectively. Eventually, a processing window for each resulting surface microstructure type is obtained experimentally and indicates the possibility to control the morphological transitions among different types.

  18. Efficient parallel implementations of approximation algorithms for guarding 1.5D terrains

    Directory of Open Access Journals (Sweden)

    Goran Martinović

    2015-03-01

    Full Text Available In the 1.5D terrain guarding problem, an x-monotone polygonal line is dened by k vertices and a G set of terrain points, i.e. guards, and a N set of terrain points which guards are to observe (guard. This involves a weighted version of the guarding problem where guards G have weights. The goal is to determine a minimum weight subset of G to cover all the points in N, including a version where points from N have demands. Furthermore, another goal is to determine the smallest subset of G, such that every point in N is observed by the required number of guards. Both problems are NP-hard and have a factor 5 approximation [3, 4]. This paper will show that if the (1+ϵ-approximate solver for the corresponding linear program is a computer, for any ϵ > 0, an extra 1+ϵ factor will appear in the final approximation factor for both problems. A comparison will be carried out the parallel implementation based on GPU and CPU threads with the Gurobi solver, leading to the conclusion that the respective algorithm outperforms the Gurobi solver on large and dense inputs typically by one order of magnitude.

  19. 46 CFR 50.10-25 - Coast Guard Symbol.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Coast Guard Symbol. 50.10-25 Section 50.10-25 Shipping... Definition of Terms Used in This Subchapter § 50.10-25 Coast Guard Symbol. (a) The term Coast Guard Symbol... impression of the Coast Guard Symbol for stamping nameplates and specimens is shown in Figure 50.10-25(b...

  20. Graphene-based tunable terahertz filter with rectangular ring ...

    Indian Academy of Sciences (India)

    A plasmonic band-pass filter based on graphene rectangular ring resonator with double narrow gaps is proposed and numerically investigated by finite-difference time-domain (FDTD) simulations. For the filter with or without gaps, the resonant frequencies can be effectively adjusted by changing the width of the graphene ...

  1. Graphene-based tunable terahertz filter with rectangular ring ...

    Indian Academy of Sciences (India)

    WEI SU

    2017-08-16

    Aug 16, 2017 ... Abstract. A plasmonic band-pass filter based on graphene rectangular ring resonator with double narrow gaps is proposed and numerically investigated by finite-difference time-domain (FDTD) simulations. For the filter with or without gaps, the resonant frequencies can be effectively adjusted by changing ...

  2. The Impact of Excluding Food Guarding from a Standardized Behavioral Canine Assessment in Animal Shelters

    Science.gov (United States)

    Mohan-Gibbons, Heather; Dolan, Emily D.; Reid, Pamela; Slater, Margaret R.; Mulligan, Hugh; Weiss, Emily

    2018-01-01

    Simple Summary Recent research has called into question the value of the food guarding assessment as a predictive tool for determining the safety of shelter dogs. This study examined the effect of eliminating the food guarding assessment in nine U.S. animal shelters. It was found that when the food guarding assessment was removed, bites or other injuries to staff or adopters did not increase. However, dogs exhibiting food guarding behavior were less likely to be adopted, had a longer shelter stay, and were more likely to be euthanized than dogs in the general population. Based on previous research and this study’s findings, the authors recommend that shelters discontinue the food guarding assessment. Abstract Many shelters euthanize or restrict adoptions for dogs that exhibit food guarding while in the animal shelter. However, previous research showed that only half the dogs exhibiting food guarding during an assessment food guard in the home. So, dogs are often misidentified as future food guarders during shelter assessments. We examined the impact of shelters omitting food guarding assessments. Nine shelters conducted a two-month baseline period of assessing for food guarding followed by a two-month investigative period during which they omitted the food guarding assessment. Dogs that guarded their food during a standardized assessment were less likely to be adopted, had a longer shelter stay, and were more likely to be euthanized. When the shelters stopped assessing for food guarding, there was no significant difference in the rate of returns of food guarding dogs, even though more dogs were adopted because fewer were identified with food guarding behavior. Additionally, the number of injuries to staff, volunteers, and adopters was low (104 incidents from a total of 14,180 dogs) and did not change when the food guarding assessment was omitted. These results support a recommendation that shelters discontinue the food guarding assessment. PMID:29419746

  3. Guarding America: Security Guards and U.S. Critical Infrastructure Protection

    National Research Council Canada - National Science Library

    Parfomak, Paul W

    2004-01-01

    The Bush Administration's 2003 National Strategy for the Physical Protection of Critical Infrastructures and Key Assets indicates that security guards are an important source of protection for critical facilities...

  4. Fact Sheets - The National Guard

    Science.gov (United States)

    National Guard About Us By the Numbers Contact Us FAQ Federal Mission History Join Us Leaders Director of March Today in Guard History Leadership CNGB VCNGB SEA DANG DARNG Joint Staff J-1 J-2 J-3 J-4 J-5 J-6 J Marshal Office of the Joint Surgeon PARC Small Business Programs Chaplain Diversity NGB-GOMO Resources

  5. Security Guards for the Future Web

    National Research Council Canada - National Science Library

    Reed, Nancy; Bryson, Dave; Garriss, James; Gosnell, Steve; Heaton, Brook; Huber, Gary; Jacobs, David; Pulvermacher, Mary; Semy, Salim; Smith, Chad; Standard, John

    2004-01-01

    .... Guard technology needs to keep pace with the evolving Web environment. The authors conjectured that a family of security guard services would be needed to provide the full range of functionality necessary to support the future Web...

  6. QTL-mapping in mink (Neovison vison) shows evidence for QTL for guard hair thickness, guard hair length and skin length

    DEFF Research Database (Denmark)

    Thirstrup, Janne Pia; Labouriau, Rodrigo; Guldbrandtsen, Bernt

    2011-01-01

    Fur quality in mink (Neovison vison) is a composite trait, consisting of e.g. guard hair length, guard hair thickness and density of wool. A genome wide QTL search was performed to detect QTL for fur quality traits in mink. Here we present the results of QTL analyses for guard hair length, guard...... hair thickness and density of wool. Data from an F2-cross was analysed across fourteen chromosomes using 100 microsatellites as markers with a spacing of approximately 20 cM. The two lines used for the F2-cross were Nordic wild mink and American short nap mink. In total 1,083 animals (21 wild type, 25...... short nap, 103 F1 and 934 F2) were marker typed and recorded for the three presented fur quality traits. For the QTL-analyses a regression analysis implemented in QTL Express software was used. Evidence was found for the existence of QTL for guard hair length, guard hair thickness and density of wool...

  7. The continuous 1.5D terrain guarding problem: Discretization, optimal solutions, and PTAS

    Directory of Open Access Journals (Sweden)

    Stephan Friedrichs

    2016-05-01

    Full Text Available In the NP-hard continuous 1.5D Terrain Guarding Problem (TGP we are given an $x$-monotone chain of line segments in $R^2$ (the terrain $T$, and ask for the minimum number of guards (located anywhere on $T$ required to guard all of $T$. We construct guard candidate and witness sets $G, W \\subset T$ of polynomial size such that any feasible (optimal guard cover $G^* \\subseteq G$ for $W$ is also feasible (optimal for the continuous TGP. This discretization allows us to: (1 settle NP-completeness for the continuous TGP; (2 provide a Polynomial Time Approximation Scheme (PTAS for the continuous TGP using the PTAS for the discrete TGP by Gibson et al.; (3 formulate the continuous TGP as an Integer Linear Program (IP. Furthermore, we propose several filtering techniques reducing the size of our discretization, allowing us to devise an efficient IP-based algorithm that reliably provides optimal guard placements for terrains with up to $10^6$ vertices within minutes on a standard desktop computer.

  8. Fiber-ring laser-based intracavity photoacoustic spectroscopy for trace gas sensing.

    Science.gov (United States)

    Wang, Qiang; Wang, Zhen; Chang, Jun; Ren, Wei

    2017-06-01

    We demonstrated a novel trace gas sensing method based on fiber-ring laser intracavity photoacoustic spectroscopy. This spectroscopic technique is a merging of photoacoustic spectroscopy (PAS) with a fiber-ring cavity for sensitive and all-fiber gas detection. A transmission-type PAS gas cell (resonant frequency f0=2.68  kHz) was placed inside the fiber-ring laser to fully utilize the intracavity laser power. The PAS signal was excited by modulating the laser wavelength at f0/2 using a custom-made fiber Bragg grating-based modulator. We used this spectroscopic technique to detect acetylene (C2H2) at 1531.6 nm as a proof of principle. With a low Q-factor (4.9) of the PAS cell, our sensor achieved a good linear response (R2=0.996) to C2H2 concentration and a minimum detection limit of 390 ppbv at 2-s response time.

  9. Self-healing ring-based WDM-PON

    Science.gov (United States)

    Zhou, Yang; Gan, Chaoqin; Zhu, Long

    2010-05-01

    In this paper, a survivable ring-based wavelength-division-multiplexing (WDM)-passive optical network (PON) for fiber protection is proposed. Protections for feeder fiber and distributed fiber are independent in the scheme. Optical line terminal (OLT) and optical network units (ONUs) can automatically switch to protection link when fiber failure occurs. Protection distributed fiber is not required in the scheme. Cost-effective components are used in ONUs to minimize costs of network. A simulation study is performed to demonstrate the scheme. Its result shows good performance of upstream and downstream signals.

  10. The effect of the guard location in a nuclear facility on performance criteria

    International Nuclear Information System (INIS)

    Lee, Hyun-Chul; Hwang, In-Koo; An, Jin-Soo

    2002-01-01

    Full text: The major functions of a physical protection system (PPS) are detection, delay, and response. Detection function is mainly to sense an adversary's intrusion and assess alarm events, and its physical implementation includes intrusion sensors, alarm communication systems and entry control facilities. Delay function can be accomplished through various passive and active barriers, makes adversary's advance toward his goal slow. Response function is to practically stop adversary actions. There are response guards responsible for the response function in a nuclear facility. They can be located at one or more posts to take action against adversary's progress after alarm occurred. The mostly used quantitative effectiveness measure of a PPS is the probability of interruption (PI) derived from delay time after detection and guard response time. Delay time is a variable dependent on adversary's capabilities and guard response time varies with the distance between a guard post and destination to be dispatched. According to the advanced technology of digital computing, software programs such as SAVI (System Analysis of Vulnerability to Intrusion) provide PI based on user input including adversary capability, protective elements, guard response time, and other PPS information. However guard response time is considered as a constant not a variable. That means same guard response time is always set regardless of the variable guard travel time from a post to a location where guards can interrupt the adversary's action. Since the location of guards may be easily changed in contrast to detection elements or delay elements and can be considered as a flexible mean against temporarily upgraded threat, a trial to investigate the changes of PI and CDP (Critical Detection Point) in case that guard response time is a variable was started. We defined several detection and delay elements along an adversary intrusion path and guard travel times as many as the number of detection

  11. Real-time track-less Cherenkov ring fitting trigger system based on Graphics Processing Units

    Science.gov (United States)

    Ammendola, R.; Biagioni, A.; Chiozzi, S.; Cretaro, P.; Cotta Ramusino, A.; Di Lorenzo, S.; Fantechi, R.; Fiorini, M.; Frezza, O.; Gianoli, A.; Lamanna, G.; Lo Cicero, F.; Lonardo, A.; Martinelli, M.; Neri, I.; Paolucci, P. S.; Pastorelli, E.; Piandani, R.; Piccini, M.; Pontisso, L.; Rossetti, D.; Simula, F.; Sozzi, M.; Vicini, P.

    2017-12-01

    The parallel computing power of commercial Graphics Processing Units (GPUs) is exploited to perform real-time ring fitting at the lowest trigger level using information coming from the Ring Imaging Cherenkov (RICH) detector of the NA62 experiment at CERN. To this purpose, direct GPU communication with a custom FPGA-based board has been used to reduce the data transmission latency. The GPU-based trigger system is currently integrated in the experimental setup of the RICH detector of the NA62 experiment, in order to reconstruct ring-shaped hit patterns. The ring-fitting algorithm running on GPU is fed with raw RICH data only, with no information coming from other detectors, and is able to provide more complex trigger primitives with respect to the simple photodetector hit multiplicity, resulting in a higher selection efficiency. The performance of the system for multi-ring Cherenkov online reconstruction obtained during the NA62 physics run is presented.

  12. Perceptions of Individual and Family Functioning Among Deployed Female National Guard Members.

    Science.gov (United States)

    Kelly, Patricia J; Cheng, An-Lin; Berkel, LaVerne A; Nilsson, Johanna

    2016-08-01

    Females currently make up 15% of U.S. military service members. Minimal attention has been paid to families of female National Guard members who have been deployed and their subsequent reintegration challenges. This cross-sectional Internet-based survey of female members of four National Guard units compared those who were and were not deployed. Instruments, guided by the variables of the Family Resilience Model, measured individual, family, and deployment-related factors. Bivariate analysis and ordinal logistic regression were done to assess differences between the groups. Of the 239 National Guard members surveyed, deployed women (n = 164) had significantly higher levels of posttraumatic stress disorder (PTSD; p family functioning were higher among deployed when compared with never deployed women. Results indicate community interventions that focus on strengthening coping skills of female Guard members would be useful for this population. © The Author(s) 2016.

  13. Chief, National Guard Bureau - Leadership - The National Guard

    Science.gov (United States)

    the ARNG Deputy Director of the ARNG Chief of Staff of the ARNG Command Chief Warrant Officer of the the ANG Chief of Staff of the ARNG CCW Officer of the ARNG CSM of the ARNG Bottom Links National Guard Civic Leader's Guide ARNG Vision 2020 Posture Statement Strategic Direction CNGB ARNG Financial Report

  14. Inductive fault current limiter based on multiple superconducting rings of small diameter

    International Nuclear Information System (INIS)

    Osorio, M R; Cabo, L; Veira, J A; Vidal, F

    2004-01-01

    We present a fault current limiter prototype based on the use of a secondary comprised of an array of magnetic cores of small sections, each one of them with several superconducting rings. The main advantage of this configuration is that it is easier to make small diameter superconducting rings which, in addition, are more homogeneous and allow better refrigeration. We then present detailed measurements that show that, in addition to these advantages, this prototype offers the same limitation performances than when using a unique core and a superconducting ring with an equivalent area as the array of small section cores

  15. 46 CFR 108.223 - Guards on exposed equipment.

    Science.gov (United States)

    2010-10-01

    ... have hand covers, guards, or rails installed on all belts, gears, shafts, pulleys, sprockets, spindles... 46 Shipping 4 2010-10-01 2010-10-01 false Guards on exposed equipment. 108.223 Section 108.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN...

  16. Development of an Acoustic Levitation Linear Transportation System Based on a Ring-Type Structure.

    Science.gov (United States)

    Thomas, Gilles P L; Andrade, Marco A B; Adamowski, Julio Cezar; Silva, Emilio Carlos Nelli

    2017-05-01

    A linear acoustic levitation transportation system based on a ring-type vibrator is presented. The system is composed by two 21-kHz Langevin transducers connected to a ring-shaped structure formed by two semicircular sections and two flat plates. In this system, a flexural standing wave is generated along the ring structure, producing an acoustic standing wave between the vibrating ring and a plane reflector located at a distance of approximately a half wavelength from the ring. The acoustic standing wave in air has a series of pressure nodes, where small particles can be levitated and transported. The ring-type transportation system was designed and analyzed by using the finite element method. Additionally, a prototype was built and the acoustic levitation and transport of a small polystyrene particle was demonstrated.

  17. Plasmon-Induced Transparency Based on Triple Arc-Ring Resonators

    Directory of Open Access Journals (Sweden)

    Guang-Xi Dong

    2018-06-01

    Full Text Available This paper presents a plasmon-induced transparency (PIT using an easy-fabricating metamaterial composed of three pieces of metallic arc-rings on top of a dielectric substrate. The transmission of the transparent peak of 1.32 THz reaches approximately 93%. The utilization of the coupled Lorentzian oscillator model and the distribution of electromagnetic fields together explain the cause of the transparent peak. The simulation results further demonstrate that the bandwidth of the transmission peak can be narrowed by changing the sizes of the arc-rings. Moreover, an on/off effect based on the transparent peak is discussed by introducing photosensitive silicon into the air gaps of the suggested metamaterial structure.

  18. Beam-based alignment at the KEK-ATF damping ring

    International Nuclear Information System (INIS)

    Woodley, Mark D.; Nelson, Janice; Ross, Marc; Turner, James; Wolski, A.; Kubo, Kiyoshi

    2004-01-01

    The damping rings of a future linear collider will have demanding alignment and stability requirements in order to achieve the low vertical emittance necessary for high luminosity. The Accelerator Test Facility (ATF) at KEK has successfully demonstrated the vertical emittance below 5 pm that is specified for the GLC/NLC Main Damping Rings. One contribution to this accomplishment has been the use of Beam Based Alignment (BBA) techniques. The mode of operation of the ATF presents particular challenges for BBA, and we describe here how we have deduced the offsets of the BPMs with respect to the quadrupoles. We also discuss a technique that allows for direct measurements of the beam-to-quad offsets

  19. Token Ring Project

    Directory of Open Access Journals (Sweden)

    Adela Ionescu

    2007-01-01

    Full Text Available Ring topology is a simple configuration used to connect processes that communicate among themselves. A number of network standards such as token ring, token bus, and FDDI are based on the ring connectivity. This article will develop an implementation of a ring of processes that communicate among themselves via pipe links. The processes are nodes in the ring. Each process reads from its standard input and writes in its standard output. N-1 process redirects the its standard output to a standard input of the process through a pipe. When the ring-structure is designed, the project can be extended to simulate networks or to implement algorithms for mutual exclusion

  20. SU-F-I-08: CT Image Ring Artifact Reduction Based On Prior Image

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, C; Qi, H; Chen, Z; Wu, S; Xu, Y; Zhou, L [Southern Medical University, Guangzhou, Guangdong (China)

    2016-06-15

    Purpose: In computed tomography (CT) system, CT images with ring artifacts will be reconstructed when some adjacent bins of detector don’t work. The ring artifacts severely degrade CT image quality. We present a useful CT ring artifacts reduction based on projection data correction, aiming at estimating the missing data of projection data accurately, thus removing the ring artifacts of CT images. Methods: The method consists of ten steps: 1) Identification of abnormal pixel line in projection sinogram; 2) Linear interpolation within the pixel line of projection sinogram; 3) FBP reconstruction using interpolated projection data; 4) Filtering FBP image using mean filter; 5) Forwarding projection of filtered FBP image; 6) Subtraction forwarded projection from original projection; 7) Linear interpolation of abnormal pixel line area in the subtraction projection; 8) Adding the interpolated subtraction projection on the forwarded projection; 9) FBP reconstruction using corrected projection data; 10) Return to step 4 until the pre-set iteration number is reached. The method is validated on simulated and real data to restore missing projection data and reconstruct ring artifact-free CT images. Results: We have studied impact of amount of dead bins of CT detector on the accuracy of missing data estimation in projection sinogram. For the simulated case with a resolution of 256 by 256 Shepp-Logan phantom, three iterations are sufficient to restore projection data and reconstruct ring artifact-free images when the dead bins rating is under 30%. The dead-bin-induced artifacts are substantially reduced. More iteration number is needed to reconstruct satisfactory images while the rating of dead bins increases. Similar results were found for a real head phantom case. Conclusion: A practical CT image ring artifact correction scheme based on projection data is developed. This method can produce ring artifact-free CT images feasibly and effectively.

  1. SU-F-I-08: CT Image Ring Artifact Reduction Based On Prior Image

    International Nuclear Information System (INIS)

    Yuan, C; Qi, H; Chen, Z; Wu, S; Xu, Y; Zhou, L

    2016-01-01

    Purpose: In computed tomography (CT) system, CT images with ring artifacts will be reconstructed when some adjacent bins of detector don’t work. The ring artifacts severely degrade CT image quality. We present a useful CT ring artifacts reduction based on projection data correction, aiming at estimating the missing data of projection data accurately, thus removing the ring artifacts of CT images. Methods: The method consists of ten steps: 1) Identification of abnormal pixel line in projection sinogram; 2) Linear interpolation within the pixel line of projection sinogram; 3) FBP reconstruction using interpolated projection data; 4) Filtering FBP image using mean filter; 5) Forwarding projection of filtered FBP image; 6) Subtraction forwarded projection from original projection; 7) Linear interpolation of abnormal pixel line area in the subtraction projection; 8) Adding the interpolated subtraction projection on the forwarded projection; 9) FBP reconstruction using corrected projection data; 10) Return to step 4 until the pre-set iteration number is reached. The method is validated on simulated and real data to restore missing projection data and reconstruct ring artifact-free CT images. Results: We have studied impact of amount of dead bins of CT detector on the accuracy of missing data estimation in projection sinogram. For the simulated case with a resolution of 256 by 256 Shepp-Logan phantom, three iterations are sufficient to restore projection data and reconstruct ring artifact-free images when the dead bins rating is under 30%. The dead-bin-induced artifacts are substantially reduced. More iteration number is needed to reconstruct satisfactory images while the rating of dead bins increases. Similar results were found for a real head phantom case. Conclusion: A practical CT image ring artifact correction scheme based on projection data is developed. This method can produce ring artifact-free CT images feasibly and effectively.

  2. An Efficient Code-Based Threshold Ring Signature Scheme with a Leader-Participant Model

    Directory of Open Access Journals (Sweden)

    Guomin Zhou

    2017-01-01

    Full Text Available Digital signature schemes with additional properties have broad applications, such as in protecting the identity of signers allowing a signer to anonymously sign a message in a group of signers (also known as a ring. While these number-theoretic problems are still secure at the time of this research, the situation could change with advances in quantum computing. There is a pressing need to design PKC schemes that are secure against quantum attacks. In this paper, we propose a novel code-based threshold ring signature scheme with a leader-participant model. A leader is appointed, who chooses some shared parameters for other signers to participate in the signing process. This leader-participant model enhances the performance because every participant including the leader could execute the decoding algorithm (as a part of signing process upon receiving the shared parameters from the leader. The time complexity of our scheme is close to Courtois et al.’s (2001 scheme. The latter is often used as a basis to construct other types of code-based signature schemes. Moreover, as a threshold ring signature scheme, our scheme is as efficient as the normal code-based ring signature.

  3. A model of PCF in guarded type theory

    DEFF Research Database (Denmark)

    Paviotti, Marco; Møgelberg, Rasmus Ejlers; Birkedal, Lars

    2015-01-01

    Guarded recursion is a form of recursion where recursive calls are guarded by delay modalities. Previous work has shown how guarded recursion is useful for constructing logics for reasoning about programming languages with advanced features, as well as for constructing and reasoning about element...... adequate. The model construction is related to Escardo's metric model for PCF, but here everything is carried out entirely in type theory with guarded recursion, including the formulation of the operational semantics, the model construction and the proof of adequacy...... of coinductive types. In this paper we investigate how type theory with guarded recursion can be used as a metalanguage for denotational semantics useful both for constructing models and for proving properties of these. We do this by constructing a fairly intensional model of PCF and proving it computationally...

  4. A Model of PCF in Guarded Type Theory

    DEFF Research Database (Denmark)

    Paviotti, Marco; Møgelberg, Rasmus Ejlers; Birkedal, Lars

    2015-01-01

    Guarded recursion is a form of recursion where recursive calls are guarded by delay modalities. Previous work has shown how guarded recursion is useful for constructing logics for reasoning about programming languages with advanced features, as well as for constructing and reasoning about element...... adequate. The model construction is related to Escardo's metric model for PCF, but here everything is carried out entirely in type theory with guarded recursion, including the formulation of the operational semantics, the model construction and the proof of adequacy....... of coinductive types. In this paper we investigate how type theory with guarded recursion can be used as a metalanguage for denotational semantics useful both for constructing models and for proving properties of these. We do this by constructing a fairly intensional model of PCF and proving it computationally...

  5. Surfing for mouth guards: assessing quality of online information.

    Science.gov (United States)

    Magunacelaya, Macarena B; Glendor, Ulf

    2011-10-01

    The Internet is an easily accessible and commonly used source of health-related information, but evaluations of the quality of this information within the dental trauma field are still lacking. The aims of this study are (i) to present the most current scientific knowledge regarding mouth guards used in sport activities, (ii) to suggest a scoring system to evaluate the quality of information pertaining to mouth guard protection related to World Wide Web sites and (iii) to employ this scoring system when seeking reliable mouth guard-related websites. First, an Internet search using the keywords 'athletic injuries/prevention and control' and 'mouth protector' or 'mouth guards' in English was performed on PubMed, Cochrane, SvedMed+ and Web of Science to identify scientific knowledge about mouth guards. Second, an Internet search using the keywords 'consumer health information Internet', 'Internet information public health' and 'web usage-seeking behaviour' was performed on PubMed and Web of Science to obtain scientific articles seeking to evaluate the quality of health information on the Web. Based on the articles found in the second search, two scoring systems were selected. Then, an Internet search using the keywords 'mouth protector', 'mouth guards' and 'gum shields' in English was performed on the search engines Google, MSN and Yahoo. The websites selected were evaluated for reliability and accuracy. Of the 223 websites retrieved, 39 were designated valid and evaluated. Nine sites scored 22 or higher. The mean total score of the 39 websites was 14.2. Fourteen websites scored higher than the mean total score, and 25 websites scored less. The highest total score, presented by a Public Institution Web site (Health Canada), was 31 from a maximum possible score of 34, and the lowest score was 0. This study shows that there is a high amount of information about mouth guards on the Internet but that the quality of this information varies. It should be the responsibility

  6. ACCELERATORS: Beam based alignment of the SSRF storage ring

    Science.gov (United States)

    Zhang, Man-Zhou; Li, Hao-Hu; Jiang, Bo-Cheng; Liu, Gui-Min; Li, De-Ming

    2009-04-01

    There are 140 beam position monitors (BPMs) in the Shanghai Synchrotron Radiation Facility (SSRF) storage ring used for measuring the closed orbit. As the BPM pickup electrodes are assembled directly on the vacuum chamber, it is important to calibrate the electrical center offset of the BPM to an adjacent quadrupole magnetic center. A beam based alignment (BBA) method which varies individual quadrupole magnet strength and observes its effects on the orbit is used to measure the BPM offsets in both the horizontal and vertical planes. It is a completely automated technique with various data processing methods. There are several parameters such as the strength change of the correctors and the quadrupoles which should be chosen carefully in real measurement. After several rounds of BBA measurement and closed orbit correction, these offsets are set to an accuracy better than 10 μm. In this paper we present the method of beam based calibration of BPMs, the experimental results of the SSRF storage ring, and the error analysis.

  7. 46 CFR 177.940 - Guards in vehicle spaces.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Guards in vehicle spaces. 177.940 Section 177.940... TONS) CONSTRUCTION AND ARRANGEMENT Rails and Guards § 177.940 Guards in vehicle spaces. On a vessel authorized to carry one or more vehicles, suitable chains, cables, or other barriers must be installed at the...

  8. Vernier effect-based multiplication of the Sagnac beating frequency in ring laser gyroscope sensors

    Science.gov (United States)

    Adib, George A.; Sabry, Yasser M.; Khalil, Diaa

    2018-02-01

    A multiplication method of the Sagnac effect scale factor in ring laser gyroscopes is presented based on the Vernier effect of a dual-coupler passive ring resonator coupled to the active ring. The multiplication occurs when the two rings have comparable lengths or integer multiples and their scale factors have opposite signs. In this case, and when the rings have similar areas, the scale factor is multiplied by ratio of their length to their length difference. The scale factor of the presented configuration is derived analytically and the lock-in effect is analyzed. The principle is demonstrated using optical fiber rings and semiconductor optical amplifier as gain medium. A scale factor multiplication by about 175 is experimentally measured, demonstrating larger than two orders of magnitude enhancement in the Sagnac effect scale factor for the first time in literature, up to the authors' knowledge.

  9. 46 CFR 116.940 - Guards in vehicle spaces.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Guards in vehicle spaces. 116.940 Section 116.940... ARRANGEMENT Rails and Guards § 116.940 Guards in vehicle spaces. On a vessel authorized to carry one or more vehicles, suitable chains, cables, or other barriers must be installed at the end of each vehicle runway...

  10. The Hi-Ring DCN Architecture

    DEFF Research Database (Denmark)

    Galili, Michael; Kamchevska, Valerija; Ding, Yunhong

    2016-01-01

    We will review recent work on the proposed hierarchical ring-based architecture (HiRing) proposed for data center networks. We will discuss the architecture and initial demonstrations of optical switching performance and time-domain synchronization......We will review recent work on the proposed hierarchical ring-based architecture (HiRing) proposed for data center networks. We will discuss the architecture and initial demonstrations of optical switching performance and time-domain synchronization...

  11. Physics of quantum rings

    International Nuclear Information System (INIS)

    Fomin, Vladimir M.

    2014-01-01

    Presents the new class of materials of quantum rings. Provides an elemental basis for low-cost high-performance devices promising for electronics, optoelectronics, spintronics and quantum information processing. Explains the physical properties of quantum rings to cover a gap in scientific literature. Presents the application of most advanced nanoengineering and nanocharacterization techniques. This book deals with a new class of materials, quantum rings. Innovative recent advances in experimental and theoretical physics of quantum rings are based on the most advanced state-of-the-art fabrication and characterization techniques as well as theoretical methods. The experimental efforts allow to obtain a new class of semiconductor quantum rings formed by capping self-organized quantum dots grown by molecular beam epitaxy. Novel optical and magnetic properties of quantum rings are associated with non-trivial topologies at the nanoscale. An adequate characterization of quantum rings is possible on the basis of modern characterization methods of nanostructures, such as Scanning Tunneling Microscopy. A high level of complexity is demonstrated to be needed for a dedicated theoretical model to adequately represent the specific features of quantum rings. The findings presented in this book contribute to develop low-cost high-performance electronic, spintronic, optoelectronic and information processing devices based on quantum rings.

  12. Issues related to choosing a guard force structure

    International Nuclear Information System (INIS)

    Auerback, C.; Cusack, J.; Green, L.; Higinbotham, W.; Indusi, J.; Marcuse, W.; Weinstock, E.

    1975-01-01

    The establishment of a federal security force has been suggested as an additional step to protect nuclear material. The force would be given the responsibility for guarding nuclear facilities and shipments of nuclear materials. This paper summarizes a study to identify the issues that are relevant to choosing between the private guard forces that are presently employed by industry or a guard force under federal authority. To examine the issues which would be relevant, three possible types of security force structures were selected for comparison: a federal force under central authority, a private guard force employed by or under contract to a facility, and a private arrangement to employ local police officers similar to the arrangement for armed guards at airports. The issues were divided into seven categories: (1) Legal Considerations, (2) Liability, (3) Staffing and Operations, (4) Costs, (5) Relationship to Off-site Forces, (6) Management and Control, (7) Transportation

  13. Ring faults and ring dikes around the Orientale basin on the Moon.

    Science.gov (United States)

    Andrews-Hanna, Jeffrey C; Head, James W; Johnson, Brandon; Keane, James T; Kiefer, Walter S; McGovern, Patrick J; Neumann, Gregory A; Wieczorek, Mark A; Zuber, Maria T

    2018-08-01

    The Orientale basin is the youngest and best-preserved multiring impact basin on the Moon, having experienced only modest modification by subsequent impacts and volcanism. Orientale is often treated as the type example of a multiring basin, with three prominent rings outside of the inner depression: the Inner Rook Montes, the Outer Rook Montes, and the Cordillera. Here we use gravity data from NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission to reveal the subsurface structure of Orientale and its ring system. Gradients of the gravity data reveal a continuous ring dike intruded into the Outer Rook along the plane of the fault associated with the ring scarp. The volume of this ring dike is ~18 times greater than the volume of all extrusive mare deposits associated with the basin. The gravity gradient signature of the Cordillera ring indicates an offset along the fault across a shallow density interface, interpreted to be the base of the low-density ejecta blanket. Both gravity gradients and crustal thickness models indicate that the edge of the central cavity is shifted inward relative to the equivalent Inner Rook ring at the surface. Models of the deep basin structure show inflections along the crust-mantle interface at both the Outer Rook and Cordillera rings, indicating that the basin ring faults extend from the surface to at least the base of the crust. Fault dips range from 13-22° for the Cordillera fault in the northeastern quadrant, to 90° for the Outer Rook in the northwestern quadrant. The fault dips for both outer rings are lowest in the northeast, possibly due to the effects of either the direction of projectile motion or regional gradients in pre-impact crustal thickness. Similar ring dikes and ring faults are observed around the majority of lunar basins.

  14. Exe-Guard Project

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Rhett [Schweitzer Engineering Lab., Inc., Pullman, WA (United States); Marshall, Tim [Dominion Virginia Power, Richmond, VA (United States); Chavez, Adrian [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Bratus, Sergey [Dartmouth College, Hanover, NH (United States)

    2016-01-30

    The exe-Guard Project is an alliance between Dominion Virginia Power (DVP), Sandia National Laboratories (SNL), Dartmouth University, and Schweitzer Engineering Laboratories (SEL). SEL is primary recipient on this project. The exe-Guard project was selected for award under DE-FOA-0000359 with CFDA number 81.122 to address Topic Area of Interest 4: Hardened platforms and Systems. The exe-Guard project developed an antivirus solution for control system embedded devices to prevent the execution of unauthorized code and maintain settings and configuration integrity. This project created a white list antivirus solution for control systems capable of running on embedded Linux® operating systems. White list antivirus methods allow only credible programs to run through the use of digital signatures and hash functions. Once a system’s secure state is baselined, white list antivirus software denies deviations from that state because of the installation of malicious code as this changes hash results. Black list antivirus software has been effective in traditional IT environments but has negative implications for control systems. Black list antivirus uses pattern matching and behavioral analysis to identify system threats while relying on regular updates to the signature file and recurrent system scanning. Black list antivirus is vulnerable to zero day exploits which have not yet been incorporated into a signature file update. System scans hamper the performance of high availability applications, as revealed in NIST special publication 1058 which summarizes the impact of blacklist antivirus on control systems: Manual or “on-demand” scanning has a major effect on control processes in that they take CPU time needed by the control process (Sometimes close to 100% of CPU time). Minimizing the antivirus software throttle setting will reduce but not eliminate this effect. Signature updates can also take up to 100% of CPU time, but for a much shorter period than a typical

  15. Issues related to choosing a guard force structure

    International Nuclear Information System (INIS)

    Averbach, C.; Cusack, J.; Green, L.; Higinbotham, W.; Indusi, J.; Marcuse, W.; Weinstock, E.

    1975-01-01

    The establishment of a federal security force has been suggested as an additional step to protect nuclear material. The force would be given the responsibility for guarding nuclear facilities and shipments of nuclear materials. A study to identify the issues that are relevant to choosing between the private guard forces that are presently employed by industry or a guard force under federal authority is summarized. To examine the issues which would be relevant, three possible types of security force structures were selected for comparison: a federal force under central authority, a private guard force employed by or under contract to a facility, and a private arrangement to employ local police officers similar to the arrangement for armed guards at airports. The issues were divided into seven categories: (1) legal considerations, (2) liability, (3) staffing and operations, (4) costs, (5) relationship to off-site forces, (6) management and control, and (7) transportation. (U.S.)

  16. Variability in the Foraging Distribution and Diet of Cape Gannets between the Guard and Post-guard Phases of the Breeding Cycle

    Directory of Open Access Journals (Sweden)

    Jonathan A. Botha

    2018-02-01

    Full Text Available During breeding, seabirds are central place foragers and are sensitive to changes in local prey availability. As the breeding season progresses, foraging behavior and distribution is expected to change in response to possible changes in local prey availability. In addition, adult gender, and the increasing nutritional demands of a growing chick may also influence the foraging behavior of individuals. At present, relatively few studies have assessed the foraging behavior of adult birds during the late post-guard stages of chick rearing. Through a combination of GPS tracking and diet sampling we investigated the foraging distances, spatial distribution, and prey composition of adult Cape gannets (Morus capensis during the guard and post-guard stages of chick rearing. We found no clear evidence for consistent sex-specific differences in foraging distances and spatial distribution during the guard stage, although marginal differences in the location of core foraging areas during the post-guard stage were apparent. Results, however, revealed a clear increase in foraging range from the early guard to the late post-guard stage of chick rearing. During December the diet was comprised almost exclusively of anchovy (Engraulis encrasicolus, the proportion of which had decreased significantly in the diet by January. This was mirrored by a substantial increase in the proportion of saury (Scomberesox saurus. These results suggest that Cape gannets show flexibility in the foraging behavior and diet, which may be related to changes in the abundance and distribution of prey or may reflect changes in the energetic requirements of the growing offspring. This study provides the first assessment of Cape gannet foraging behavior and spatial distribution during the post-guard stage of chick rearing. The importance of considering intra-annual variability in foraging distribution when using seabird tracking data in trophic and marine spatial planning studies are

  17. A Virtual Private Local PCN Ring Network Based on ATM VP Cross—Connection

    Institute of Scientific and Technical Information of China (English)

    LinBin; MaYingjun; 等

    1995-01-01

    Avirtual private local PCNring network (VPLPR)is proposed .VPLPR is a virtual logic ring seuved for digital cordless telephone system and it works on ATM VP cross-connection mechanism.Full-distributed data bases are organized for visitor location registers(VLR)and home location register(HLR).The signaling protocols are compatible upward to B-ISDN. The architecture and some of the main characteristics of VPLPR are given.How to configure the ATM VP cross-connection ring is described.And then a protocol conversion between STM frames and ATMcells in base station controller(BSC)is presented.

  18. Noise Source Identification of a Ring-Plate Cycloid Reducer Based on Coherence Analysis

    Directory of Open Access Journals (Sweden)

    Bing Yang

    2013-01-01

    Full Text Available A ring-plate-type cycloid speed reducer is one of the most important reducers owing to its low volume, compactness, smooth and high performance, and high reliability. The vibration and noise tests of the reducer prototype are completed using the HEAD acoustics multichannel noise test and analysis system. The characteristics of the vibration and noise are obtained based on coherence analysis and the noise sources are identified. The conclusions provide the bases for further noise research and control of the ring-plate-type cycloid reducer.

  19. Moeller polarimeter for VEPP-3 storage ring based on internal polarized gas jet target

    International Nuclear Information System (INIS)

    Dyug, M.V.; Grigoriev, A.V.; Kiselev, V.A.; Lazarenko, B.A.; Levichev, E.B.; Mikaiylov, A.I.; Mishnev, S.I.; Nikitin, S.A.; Nikolenko, D.M.; Rachek, I.A.; Shestakov, Yu.V.; Toporkov, D.K.; Zevakov, S.A.; Zhilich, V.N.

    2005-01-01

    A new method to determine the polarization of an electron beam circulating in a storage ring by a non-destructive way, based on measuring the asymmetry in scattering of beam electrons on electrons of the internal polarized gas jet target, has been developed and tested at the VEPP-3 storage ring

  20. Oracle Data Guard 11gR2 administration beginner's guide

    CERN Document Server

    Baransel, Emre

    2013-01-01

    Using real-world examples and hands-on tasks, Oracle Data Guard 11gR2 Administration Beginner's Guide will give you a solid foundation in Oracle Data Guard. It has been designed to teach you everything you need to know to successfully create and operate Data Guard environments with maximum flexibility, compatibility, and effectiveness.If you are an Oracle database administrator who wants to configure and administer Data Guard configurations, then ""Oracle Data Guard 11gR2 Administration Beginner's Guide"" is for you. With a basic understanding of Oracle database administration, you'll be able

  1. Atomic-phase interference devices based on ring-shaped Bose-Einstein condensates: Two-ring case

    International Nuclear Information System (INIS)

    Anderson, B.P.; Dholakia, K.; Wright, E.M.

    2003-01-01

    We theoretically investigate the ground-state properties and quantum dynamics of a pair of adjacent ring-shaped Bose-Einstein condensates that are coupled via tunneling. This device, which is the analog of a symmetric superconducting quantum interference device, is the simplest version of what we term an atomic-phase interference device (APHID). The two-ring APHID is shown to be sensitive to rotation

  2. Denotational semantics for guarded dependent type theory

    DEFF Research Database (Denmark)

    Bizjak, Aleš; Møgelberg, Rasmus Ejlers

    2018-01-01

    We present a new model of Guarded Dependent Type Theory (GDTT), a type theory with guarded recursion and multiple clocks in which one can program with, and reason about coinductive types. Productivity of recursively defined coinductive programs and proofs is encoded in types using guarded recursion......, crucial for programming with coinductive types, types must be interpreted as presheaves orthogonal to the object of clocks. In the case of dependent types, this translates to a unique lifting condition similar to the one found in homotopy theoretic models of type theory. Since the universes defined...... by inclusions of clock variable contexts commute on the nose with type operations on the universes....

  3. Topological ring currents in the "empty" ring of benzo-annelated perylenes.

    Science.gov (United States)

    Dickens, Timothy K; Mallion, Roger B

    2011-01-27

    Cyclic conjugation in benzo-annelated perylenes is examined by means of the topological π-electron ring currents calculated for each of their constituent rings, in a study that is an exact analogy of a recent investigation by Gutman et al. based on energy-effect values for the corresponding rings in each of these structures. "Classical" approaches, such as Kekulé structures, Clar "sextet" formulas, and circuits of conjugation, predict that the central ring in perylene is "empty" and thus contributes negligibly to cyclic conjugation. However, conclusions from the present calculations of topological ring currents agree remarkably with those arising from the earlier study involving energy-effect values in that, contrary to what would be predicted from the classical approaches, rings annelated in an angular fashion relative to the central ring of these perylene structures materially increase the extent of that ring's involvement in cyclic conjugation. It is suggested that such close quantitative agreement between the predictions of these two superficially very different indices (energy effect and topological ring current) might be due to the fact that, ultimately, both depend, albeit in ostensibly quite different ways, only on an adjacency matrix that contains information about the carbon-carbon connectivity of the conjugated system in question.

  4. Polarization Insensitivity in Double-Split Ring and Triple-Split Ring Terahertz Resonators

    International Nuclear Information System (INIS)

    Wu Qian-Nan; Lan Feng; Tang Xiao-Pin; Yang Zi-Qiang

    2015-01-01

    A modified double-split ring resonator and a modified triple-split ring resonator, which offer polarization-insensitive performance, are investigated, designed and fabricated. By displacing the two gaps of the conventional double-split ring resonator away from the center, the second resonant frequency for the 0° polarized wave and the resonant frequency for the 90° polarized wave become increasingly close to each other until they are finally identical. Theoretical and experimental results show that the modified double-split ring resonator and the modified triple-split ring resonator are insensitive to different polarized waves and show strong resonant frequency dips near 433 and 444 GHz, respectively. The results of this work suggest new opportunities for the investigation and design of polarization-dependent terahertz devices based on split ring resonators. (paper)

  5. Laparoscopic appendicectomy using endo-ring applicator and fallope rings

    International Nuclear Information System (INIS)

    Ali, Iyoob V; Maliekkal, Joji I

    2009-01-01

    Wider adoption of laparoscopic appendicectomy (LA) is limited by problems in securing the appendiceal base as well as the cost and the duration compared with the open procedure. The objective of this study was to assess the feasibility and efficacy of a new method for securing the appendiceal base in LA, so as to make the entire procedure simpler and cheaper, and hence, more popular. Twenty-five patients who were candidates for appendicectomy (emergency as well as elective) and willing for the laparoscopic procedure were selected for this study. Ports used were 10 mm at the umbilicus, 5 mm at the lower right iliac fossa, and 10 mm at the left iliac fossa. Extremely friable, ruptured, or turgid organs of diameters larger than 8 mm were excluded from the study. The mesoappendix was divided close to the appendix by diathermy. Fallope rings were applied to the appendiceal base using a special ring applicator, and the appendix was divided and extracted through the lumen of the applicator. The procedure was successful in 23 (92%) cases, and the mean duration of the procedure was 20 minutes (15-32 minutes). There were no procedural complications seen during a median follow-up of two weeks. The equipment and rings were cheaper when compared with that of the standard methods of securing the base of the appendix. LA using fallope rings is a safe, simple, easy-to-learn, and economically viable method. (author)

  6. Roles for National Guard Components: Current Thoughts and Future Possibilities

    Science.gov (United States)

    2000-04-01

    Gen Russell C. Davis, chief, National Guard Bureau, remarks at the National Chamber of Commerce , Washington, D.C., June 1999. 5 Moskos and Burk, 176...Lt Gen Russell C. Davis, chief, National Guard Bureau, remarks at the National Chamber of Commerce , Washington, D.C., June 9 1999. 5 National Guard...National Guard Bureau, remarks to the National Chamber of Commerce , Washington, D.C., June 1999, n.p. On-line. Internet, 27 February 2000, available at

  7. Elastic-plastic dynamic behavior of guard pipes due to sudden opening of longitudinal cracks in the inner pipe and crash to the guard pipe wall

    International Nuclear Information System (INIS)

    Theuer, E.; Heller, M.

    1979-01-01

    Integrity of guard pipes is an important parameter in the design of nuclear steam supply systems. A guard pipe shall withstand all kinds of postulated inner pipe breaks without failure. Sudden opening of a crack in the inner pipe and crash of crack borders to the guard pipe wall represent a shock problem where complex phenomena of dynamic plastification as well as dynamic behavior of the entire system have to be taken in consideration. The problem was analyzed by means of Finite Element computation using the general purpose program MARC. Equation of motion was resolved by direct integration using the Newmark β-operator. Analysis shows that after 1,2 m sec crack borders touch the guard pipe wall for the first time. At this moment a considerable amount of local plastification appears in the inner pipe wall, while the guard pipe is nearly unstressed. After initial touching, the crack borders begin to slip along the guard pipe wall. Subsequently, a short withdrawal of the crack borders and a new crash occur, while the inner pipe rolls along the guard pipe wall. The analysis procedure described is suitable for designing numerous guard pipe geometries as well as U-Bolt restraint systems which have to withstand high-energy pipe rupture impact. (orig.)

  8. 30 CFR 77.1011 - Drill holes; guarding.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drill holes; guarding. 77.1011 Section 77.1011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... Control § 77.1011 Drill holes; guarding. Drill holes large enough to constitute a hazard shall be covered...

  9. 41 CFR 50-204.5 - Machine guarding.

    Science.gov (United States)

    2010-07-01

    ... be such that it does not offer an accident hazard in itself. (c) Point of Operation Guarding. (1) Point of operation is the area on a machine where work is actually performed upon the material being... guarding device shall be so designed and constructed so as to prevent the operator from having any part of...

  10. Building an FTP guard

    Energy Technology Data Exchange (ETDEWEB)

    Sands, P.D.

    1998-08-01

    Classified designs usually include lesser classified (including unclassified) components. An engineer working on such a design needs access to the various sub-designs at lower classification levels. For simplicity, the problem is presented with only two levels: high and low. If the low-classification component designs are stored in the high network, they become inaccessible to persons working on a low network. In order to keep the networks separate, the component designs may be duplicated in all networks, resulting in a synchronization problem. Alternatively, they may be stored in the low network and brought into the high network when needed. The latter solution results in the use of sneaker-net (copying the files from the low system to a tape and carrying the tape to a high system) or a file transfer guard. This paper shows how an FTP Guard was constructed and implemented without degrading the security of the underlying B3 platform. The paper then shows how the guard can be extended to an FTP proxy server or an HTTP proxy server. The extension is accomplished by allowing the high-side user to select among items that already exist on the low-side. No high-side data can be directly compromised by the extension, but a mechanism must be developed to handle the low-bandwidth covert channel that would be introduced by the application.

  11. 30 CFR 56.12023 - Guarding electrical connections and resistor grids.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Guarding electrical connections and resistor... MINES Electricity § 56.12023 Guarding electrical connections and resistor grids. Electrical connections and resistor grids that are difficult or impractical to insulate shall be guarded, unless protection...

  12. 14-3-3 Proteins in Guard Cell Signaling.

    Science.gov (United States)

    Cotelle, Valérie; Leonhardt, Nathalie

    2015-01-01

    Guard cells are specialized cells located at the leaf surface delimiting pores which control gas exchanges between the plant and the atmosphere. To optimize the CO2 uptake necessary for photosynthesis while minimizing water loss, guard cells integrate environmental signals to adjust stomatal aperture. The size of the stomatal pore is regulated by movements of the guard cells driven by variations in their volume and turgor. As guard cells perceive and transduce a wide array of environmental cues, they provide an ideal system to elucidate early events of plant signaling. Reversible protein phosphorylation events are known to play a crucial role in the regulation of stomatal movements. However, in some cases, phosphorylation alone is not sufficient to achieve complete protein regulation, but is necessary to mediate the binding of interactors that modulate protein function. Among the phosphopeptide-binding proteins, the 14-3-3 proteins are the best characterized in plants. The 14-3-3s are found as multiple isoforms in eukaryotes and have been shown to be involved in the regulation of stomatal movements. In this review, we describe the current knowledge about 14-3-3 roles in the regulation of their binding partners in guard cells: receptors, ion pumps, channels, protein kinases, and some of their substrates. Regulation of these targets by 14-3-3 proteins is discussed and related to their function in guard cells during stomatal movements in response to abiotic or biotic stresses.

  13. Analytical model for double split ring resonators with arbitrary ring width

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Jensen, Thomas; Krozer, Viktor

    2008-01-01

    For the first time, the analytical model for a double split ring resonator with unequal width rings is developed. The proposed models for the resonators with equal and unequal widths are based on an impedance matrix representation and provide the prediction of performance in a wide frequency range...

  14. An innovative seismic bracing system based on a superelastic shape memory alloy ring

    International Nuclear Information System (INIS)

    Gao, Nan; Jeon, Jong-Su; DesRoches, Reginald; Hodgson, Darel E

    2016-01-01

    Shape memory alloys (SMAs) have great potential in seismic applications because of their remarkable superelasticity. Seismic bracing systems based on SMAs can mitigate the damage caused by earthquakes. The current study investigates a bracing system based on an SMA ring which is capable of both re-centering and energy dissipation. This lateral force resisting system is a cross-braced system consisting of an SMA ring and four tension-only cable assemblies, which can be applied to both new construction and seismic retrofit. The performance of this bracing system is examined through a quasi-static cyclic loading test and finite element (FE) analysis. This paper describes the experimental design in detail, discusses the experimental results, compares the performance with other bracing systems based on SMAs, and presents an Abaqus FE model calibrated on the basis of experimental results to simulate the superelastic behavior of the SMA ring. The experimental results indicate that the seismic performance of this system is promising in terms of damping and re-centering. The FE model can be used in the simulation of building structures using the proposed bracing system. (paper)

  15. Correlation Investigation as to the Mental Health of the Prison Guard in Xi'an Police Station

    Institute of Scientific and Technical Information of China (English)

    Feng Xue

    2005-01-01

    Based on the symptom check list 90,EPQ scale and the simplified coping style questionaire,the author made a relative study on psychological health,personality character and coping style of 267 prison guard of police bureau in Xi'an city .The study shows this:   ①The mental health,personality character and coping style could be effected by many factors,such as gender,age,educational background,income,origin,satisfactory degree of working enviroment and some others.The mental health,personality character and coping style could effect each other.②The psychological health state of 267 prison guard is much worse than that of domestic common people.③The personality character of 267 prison guard shows much higher hostility and lower nervous than that of domestic common people.④The coping style of 267 prison guard often take positive coping styles.⑤Psychological health,personality character and coping style of prison guard are closely related.

  16. 30 CFR 77.509 - Transformers; installation and guarding.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Transformers; installation and guarding. 77.509... COAL MINES Electrical Equipment-General § 77.509 Transformers; installation and guarding. (a... feet from any energized parts, casings, or wiring. (b) Transformer stations shall be enclosed to...

  17. Theoretical Model for the Performance of Liquid Ring Pump Based on the Actual Operating Cycle

    Directory of Open Access Journals (Sweden)

    Si Huang

    2017-01-01

    Full Text Available Liquid ring pump is widely applied in many industry fields due to the advantages of isothermal compression process, simple structure, and liquid-sealing. Based on the actual operating cycle of “suction-compression-discharge-expansion,” a universal theoretical model for performance of liquid ring pump was established in this study, to solve the problem that the theoretical models deviated from the actual performance in operating cycle. With the major geometric parameters and operating conditions of a liquid ring pump, the performance parameters such as the actual capacity for suction and discharge, shaft power, and global efficiency can be conveniently predicted by the proposed theoretical model, without the limitation of empiric range, performance data, or the detailed 3D geometry of pumps. The proposed theoretical model was verified by experimental performances of liquid ring pumps and could provide a feasible tool for the application of liquid ring pump.

  18. 30 CFR 77.510 - Resistors; location and guarding.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Resistors; location and guarding. 77.510 Section 77.510 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... COAL MINES Electrical Equipment-General § 77.510 Resistors; location and guarding. Resistors, heaters...

  19. National Guard Forces in the Cyber Domain

    Science.gov (United States)

    2015-05-22

    TITLE AND SUBTITLE National Guard Forces in the Cyber Domain 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...Soldiers. Army Cyber Command (ARCYBER) commander, Lieutenant General Edward Cardon stated that Guard will begin to build combat power with...90 2014 Quadrennial Defense Review, 15. 91 Ibid. 92 Edward C. Cardon , "ARMY.MIL, The Official Homepage of the United

  20. RINGED ACCRETION DISKS: EQUILIBRIUM CONFIGURATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Pugliese, D.; Stuchlík, Z., E-mail: d.pugliese.physics@gmail.com, E-mail: zdenek.stuchlik@physics.cz [Institute of Physics and Research Centre of Theoretical Physics and Astrophysics, Faculty of Philosophy and Science, Silesian University in Opava, Bezručovo náměstí 13, CZ-74601 Opava (Czech Republic)

    2015-12-15

    We investigate a model of a ringed accretion disk, made up by several rings rotating around a supermassive Kerr black hole attractor. Each toroid of the ringed disk is governed by the general relativity hydrodynamic Boyer condition of equilibrium configurations of rotating perfect fluids. Properties of the tori can then be determined by an appropriately defined effective potential reflecting the background Kerr geometry and the centrifugal effects. The ringed disks could be created in various regimes during the evolution of matter configurations around supermassive black holes. Therefore, both corotating and counterrotating rings have to be considered as being a constituent of the ringed disk. We provide constraints on the model parameters for the existence and stability of various ringed configurations and discuss occurrence of accretion onto the Kerr black hole and possible launching of jets from the ringed disk. We demonstrate that various ringed disks can be characterized by a maximum number of rings. We present also a perturbation analysis based on evolution of the oscillating components of the ringed disk. The dynamics of the unstable phases of the ringed disk evolution seems to be promising in relation to high-energy phenomena demonstrated in active galactic nuclei.

  1. Planetary Rings

    Science.gov (United States)

    Nicholson, P. D.

    2001-11-01

    A revolution in the studies in planetary rings studies occurred in the period 1977--1981, with the serendipitous discovery of the narrow, dark rings of Uranus, the first Voyager images of the tenuous jovian ring system, and the many spectacular images returned during the twin Voyager flybys of Saturn. In subsequent years, ground-based stellar occultations, HST observations, and the Voyager flybys of Uranus (1986) and Neptune (1989), as well as a handful of Galileo images, provided much additional information. Along with the completely unsuspected wealth of detail these observations revealed came an unwelcome problem: are the rings ancient or are we privileged to live at a special time in history? The answer to this still-vexing question may lie in the complex gravitational interactions recent studies have revealed between the rings and their retinues of attendant satellites. Among the four known ring systems, we see elegant examples of Lindblad and corotation resonances (first invoked in the context of galactic disks), electromagnetic resonances, spiral density waves and bending waves, narrow ringlets which exhibit internal modes due to collective instabilities, sharp-edged gaps maintained via tidal torques from embedded moonlets, and tenuous dust belts created by meteoroid impact onto parent bodies. Perhaps most puzzling is Saturn's multi-stranded, clumpy F ring, which continues to defy a simple explanation 20 years after it was first glimpsed in grainy images taken by Pioneer 11. Voyager and HST images reveal a complex, probably chaotic, dynamical interaction between unseen parent bodies within this ring and its two shepherd satellites, Pandora and Prometheus. The work described here reflects contributions by Joe Burns, Jeff Cuzzi, Luke Dones, Dick French, Peter Goldreich, Colleen McGhee, Carolyn Porco, Mark Showalter, and Bruno Sicardy, as well as those of the author. This research has been supported by NASA's Planetary Geology and Geophysics program and the

  2. 33 CFR 125.11 - Form of Coast Guard Port Security Card.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Form of Coast Guard Port Security... WATERFRONT FACILITIES OR VESSELS § 125.11 Form of Coast Guard Port Security Card. The Coast Guard Port... data. ...

  3. Coast Guard Acquisitions: Enhanced Oversight of Testing Could Benefit National Security Cutter Program and Future DHS Acquisitions

    Science.gov (United States)

    2016-02-03

    based on our January 2016 report on the NSC’s IOT &E event.2 I will address issues related to (1) the results of the NSC’s IOT &E, (2) the Coast Guard’s...before the testing is complete, meaning that the Coast Guard will be operating 6 NSCs before it has resolved issues from IOT &E and knows the... IOT &E event, the Coast Guard had nearly four years of experience operating the NSCs. The Coast Guard has encountered several issues that require

  4. Δg: The new aromaticity index based on g-factor calculation applied for polycyclic benzene rings

    Science.gov (United States)

    Ucun, Fatih; Tokatlı, Ahmet

    2015-02-01

    In this work, the aromaticity of polycyclic benzene rings was evaluated by the calculation of g-factor for a hydrogen placed perpendicularly at geometrical center of related ring plane at a distance of 1.2 Å. The results have compared with the other commonly used aromatic indices, such as HOMA, NICSs, PDI, FLU, MCI, CTED and, generally been found to be in agreement with them. So, it was proposed that the calculation of the average g-factor as Δg could be applied to study the aromaticity of polycyclic benzene rings without any restriction in the number of benzene rings as a new magnetic-based aromaticity index.

  5. US Coast Guard national spill response resource inventory

    International Nuclear Information System (INIS)

    Giraitis, D.M.

    1993-01-01

    The Oil Pollution Act of 1990 (OPA 90) mandated the establishment of a National Response Unit, now renamed the National Strike Force Coordination Center (NSFCC). Among the duties OPA 90 assigned to this new Coast Guard unit was to compile and maintain a comprehensive list of spill removal resources, personnel, and equipment that is available to Federal and State agencies and to the public. The Coast Guard's Research and Development Center has been developing this project, the Response Resource Inventory (RRI), for one year. The RRI is expected to be operational, with resource data from industry in the data base, by the time of the International Oil Spill Conference in March 1993. The RRI will contain data on skimmers, specialized oil recovery vessels, oil/water separators, dispersants and delivery systems, etc. Previous attempts to maintain a national data base of these response resources, including an earlier Coast Guard system called the Spill Cleanup Equipment Inventory System (SKIM), fell into disuse for a number of reasons. Inaccuracies caused by inadvertent double counting of equipment and outdated information coupled with difficulties in accessing the information were common shortfalls of early systems. During the development of the RRI, user-group meetings were held to determine system requirements and study the failures of previous systems. Methods of obtaining and entering data were a major concern during RRI development. A data collection system that supplies the resource holder with a DOS-formatted diskette containing a collection program will be used. The program will make extensive use of pick lists to minimize the data entry burden on the resource holder and maintain standard entries. When the program is completed, the diskette will be mailed to the NSFCC, where the data will be transferred quickly to the RRI data base. Easy access to the data for the public and industry will be afforded mainly through a computer bulletin board

  6. NEUTRINO FACTORY BASED ON MUON-STORAGE-RINGS TO MUON COLLIDERS: PHYSICS AND FACILITIES

    International Nuclear Information System (INIS)

    PARSA, Z.

    2001-01-01

    Intense muon sources for the purpose of providing intense high energy neutrino beams (ν factory) represents very interesting possibilities. If successful, such efforts would significantly advance the state of muon technology and provides intermediate steps in technologies required for a future high energy muon collider complex. High intensity muon: production, capture, cooling, acceleration and multi-turn muon storage rings are some of the key technology issues that needs more studies and developments, and will briefly be discussed here. A muon collider requires basically the same number of muons as for the muon storage ring neutrino factory, but would require more cooling, and simultaneous capture of both ± μ. We present some physics possibilities, muon storage ring based neutrino facility concept, site specific examples including collaboration feasibility studies, and upgrades to a full collider

  7. NEUTRINO FACTORY BASED ON MUON-STORAGE-RINGS TO MUON COLLIDERS: PHYSICS AND FACILITIES.

    Energy Technology Data Exchange (ETDEWEB)

    PARSA,Z.

    2001-06-18

    Intense muon sources for the purpose of providing intense high energy neutrino beams ({nu} factory) represents very interesting possibilities. If successful, such efforts would significantly advance the state of muon technology and provides intermediate steps in technologies required for a future high energy muon collider complex. High intensity muon: production, capture, cooling, acceleration and multi-turn muon storage rings are some of the key technology issues that needs more studies and developments, and will briefly be discussed here. A muon collider requires basically the same number of muons as for the muon storage ring neutrino factory, but would require more cooling, and simultaneous capture of both {+-} {mu}. We present some physics possibilities, muon storage ring based neutrino facility concept, site specific examples including collaboration feasibility studies, and upgrades to a full collider.

  8. Tens of GHz Tantalum pentoxide-based micro-ring all-optical modulator for Si photonics

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chung-Lun; Chi, Wen-Chun; Chiu, Yi-Jen; Lin, Yuan-Yao; Hung, Yung-Jr; Chu, Ann-Kuo [Department of Photonics, National Sun Yat-sen University, Kaohsiung, Taiwan (China); Hsieh, Cheng-Hsuan; Lin, Gong-Ru [Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei (China); Shih, Min-Hsiung [Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, Hsinchu, Taiwan (China); Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan (China); Department of Physics, National Sun Yat-sen University, Kaohsiung, Taiwan (China); Lee, Chao-Kuei [Department of Photonics, National Sun Yat-sen University, Kaohsiung, Taiwan (China); Department of Physics, National Sun Yat-sen University, Kaohsiung, Taiwan (China)

    2017-03-15

    A tantalum pentoxide-based (Ta{sub 2}O{sub 5}-based) micro-ring all-optical modulator was fabricated. The refractive index inside the micro-ring cavity was modified using the Kerr effect by injecting a pumped pulse. The transmittance of the ring resonator was controlled to achieve all-optical modulation at the wavelength of the injected probe. When 12 GHz pulses with a peak power of 1.2 W were coupled in the ring cavity, the transmission spectrum of the Ta{sub 2}O{sub 5} resonator was red-shifted by 0.04 nm because of the Kerr effect. The relationship between the modulation depth and gap of the Ta{sub 2}O{sub 5} directional coupler is discussed. An optimized gap of 1100 nm was obtained, and a maximum buildup factor of 11.7 with 84% modulation depth was achieved. The nonlinear refractive index of Ta{sub 2}O{sub 5} at 1.55 μm was estimated as 3.4 x 10{sup -14} cm{sup 2}/W based on the Kerr effect, which is almost an order of magnitude higher than that of Si{sub 3}N{sub 4}. All results indicate that Ta{sub 2}O{sub 5} has potential for use in nonlinear waveguide applications with modulation speeds as high as tens of GHz. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. Security Guards and Counter-terrorism: Tourism and Gaps in Terrorism Prevention

    Directory of Open Access Journals (Sweden)

    Luke Howie

    2014-11-01

    Full Text Available Organisation operating in the tourism industry are high priority targets for terrorists. In the aftermath of the 9/11 attacks tourism destinations, hotels and modes of public transportation have regularly been targeted by terrorists seeking to convey their violent message. As such, leaders and managers in the tourism industry carefully plan their security and counter-terrorism responses, often involving the hiring of security guards. It is here that I believe a significant gap in counter-terrorism preparedness exists. I argue that protecting tourism destinations is only possible if consideration is given the effectiveness of security guards and understanding that their well-being will impact upon their ability to deliver security. I want to draw attention to the often ignored social role of security guards. On 9/11, 42 security guards died whilst helping save the lives of thousands. They performed their jobs admirably, despite being low-paid, under-appreciated workers. In this paper I explore the social role of security guards in the context of tourism security. By drawing on representations of security guards in popular culture and reports on the state of the security guard industry. I argue that the lack of attention on the quality and well-being of guards is a significant black-spot in tourism security and terrorism preparedness.

  10. Women's Fertility Status Alters Other Women's Jealousy and Mate Guarding.

    Science.gov (United States)

    Hurst, Ashalee C; Alquist, Jessica L; Puts, David A

    2017-02-01

    Across three studies, we tested the hypothesis that women exhibit greater jealousy and mate guarding toward women who are in the high (vs. low) fertility phase of their cycle. Women who imagined their partner with a woman pictured at high fertility reported more jealousy than women who imagined their partner with a woman pictured at low fertility (Studies 1 and 2). A meta-analysis across studies manipulating fertility status of the pictured woman found a significant effect of fertility status on both jealousy and mate guarding. Women with attractive partners viewed fertile-phase women as less trustworthy, which led to increased mate guarding (Study 2). In Study 3, the closer women were to peak fertility, the more instances they reported of other women acting jealously and mate guarding toward them. These studies provide evidence that women selectively exhibit jealousy and mate guarding toward women who are near peak fertility.

  11. Novel microwave photonic fractional Hilbert transformer using a ring resonator-based optical all-pass filter.

    Science.gov (United States)

    Zhuang, Leimeng; Khan, Muhammad Rezaul; Beeker, Willem; Leinse, Arne; Heideman, René; Roeloffzen, Chris

    2012-11-19

    We propose and demonstrate a novel wideband microwave photonic fractional Hilbert transformer implemented using a ring resonator-based optical all-pass filter. The full programmability of the ring resonator allows variable and arbitrary fractional order of the Hilbert transformer. The performance analysis in both frequency and time domain validates that the proposed implementation provides a good approximation to an ideal fractional Hilbert transformer. This is also experimentally verified by an electrical S21 response characterization performed on a waveguide realization of a ring resonator. The waveguide-based structure allows the proposed Hilbert transformer to be integrated together with other building blocks on a photonic integrated circuit to create various system-level functionalities for on-chip microwave photonic signal processors. As an example, a circuit consisting of a splitter and a ring resonator has been realized which can perform on-chip phase control of microwave signals generated by means of optical heterodyning, and simultaneous generation of in-phase and quadrature microwave signals for a wide frequency range. For these functionalities, this simple and on-chip solution is considered to be practical, particularly when operating together with a dual-frequency laser. To our best knowledge, this is the first-time on-chip demonstration where ring resonators are employed to perform phase control functionalities for optical generation of microwave signals by means of optical heterodyning.

  12. Use of ISEM in studying the impact of guard tactics on facility safeguards system effectiveness

    International Nuclear Information System (INIS)

    Engi, D.; Boozer, D.D.

    1977-07-01

    The Insider Safeguards Effectiveness Model (ISEM) is a stochastic, discrete event, Monte-Carlo Simulation Model used to assess the effectiveness of physical protection systems for facilities which store, process, or use SNM. ISEM simulates the interaction of a group of insiders. The sensor control and alarm locations are correlated with the authorized access areas of the insider(s) and, if the insider has the appropriate access, the probability of an insider successfully defeating a sensor control or alarm is computed based upon the surveillance subsystems and the insider's attributes. Following an alarm and an assessment, actions are initiated by the safeguards system. These actions typically involve dispatching guards to specific locations within the facility. Since the specific guard responses must be predetermined, a safeguards system should be evolved from a consideration of a wide spectrum of feasible adversary strategies. The sensitivity of safeguards system effectiveness to a variety of guard tactics is explored in this paper. The evolution of comprehensive guard tactics for protecting a hypothetical facility is demonstrated. Attention is focused on the potential threat posed by insiders and the necessity of well conceived guard tactics in dealing with this threat

  13. Updating ARI Educational Benefits Usage Data Bases for Army Regular, Reserve, and Guard: 2005 - 2006

    National Research Council Canada - National Science Library

    Young, Winnie

    2007-01-01

    This report describes the updating of ARI's educational benefits usage database with Montgomery GI Bill and Army College Fund data for Army Regular, Reserve, and Guard components over the 2005 and 2006 period...

  14. Connectivity for underway Coast Guard patrol boats

    OpenAIRE

    Busch, Gregory C.

    1997-01-01

    Approved for public release; distribution is unlimited This thesis examines the US Coast Guard patrol boat's ability to effectively exchange operational data while underway. The patrol boat is currently unable to obtain tactical law enforcement information from the central Law Enforcement Information System 2 (LEIS 2) database while on patrol. LEIS 2 provides access to law enforcement information from Coast Guard, FBI, and state and local law enforcement agencies. Availability of this info...

  15. Model-Based, Closed-Loop Control of PZT Creep for Cavity Ring-Down Spectroscopy.

    Science.gov (United States)

    McCartt, A D; Ognibene, T J; Bench, G; Turteltaub, K W

    2014-09-01

    Cavity ring-down spectrometers typically employ a PZT stack to modulate the cavity transmission spectrum. While PZTs ease instrument complexity and aid measurement sensitivity, PZT hysteresis hinders the implementation of cavity-length-stabilized, data-acquisition routines. Once the cavity length is stabilized, the cavity's free spectral range imparts extreme linearity and precision to the measured spectrum's wavelength axis. Methods such as frequency-stabilized cavity ring-down spectroscopy have successfully mitigated PZT hysteresis, but their complexity limits commercial applications. Described herein is a single-laser, model-based, closed-loop method for cavity length control.

  16. Male songbirds provide indirect parental care by guarding females during incubation

    Science.gov (United States)

    Fedy, B.C.; Martin, T.E.

    2009-01-01

    Across many taxa, guarding of fertile mates is a widespread tactic that enhances paternity assurance. However, guarding of mates can also occur during the nonfertile period, and the fitness benefits of this behavior are unclear. Male songbirds, for example, sometimes guard nonfertile females during foraging recesses from incubation. We hypothesized that guarding postreproductive mates may have important, but unrecognized, benefits by enhancing female foraging efficiency, thereby increasing time spent incubating eggs. We tested the hypothesis in 2 songbird species by examining female behavior during natural and experimentally induced absences of males. Male absence caused increased vigilance in foraging females that decreased their efficiency and resulted in less time spent incubating eggs. Male guarding of nonfertile females can thus provide a previously unrecognized form of indirect parental care.

  17. What is a "good" encoding of guarded choice?

    DEFF Research Database (Denmark)

    Nestmann, Uwe

    2000-01-01

    into the latter that preserves divergence-freedom and symmetries. This paper argues that there are nevertheless "good" encodings between these calculi. In detail, we present a series of encodings for languages with (1) input-guarded choice, (2) both input and output-guarded choice, and (3) mixed-guarded choice......, and investigate them with respect to compositionality and divergence-freedom. The first and second encoding satisfy all of the above criteria, but various "good" candidates for the third encoding-inspired by an existing distributed implementation-invalidate one or the other criterion, While essentially confirming...... Palamidessi's result, our study suggests that the combination of strong compositionality and divergence-freedom is too strong for more practical purposes. (C) 2000 Academic Press....

  18. Design and evaluation of a low thermal electromotive force guarded scanner for resistance measurements

    Science.gov (United States)

    Jarrett, Dean G.; Marshall, James A.; Marshall, Thomas A.; Dziuba, Ronald F.

    1999-06-01

    The design and testing of a low thermal electromotive force guarded scanner, developed to provide completely guarded switching when used with actively guarded resistance bridge networks, is described. The design provides a continuous guard circuit trace on the scanner circuit boards that surrounds the relay contacts and protects the measurement circuit from leakages to ground. Modification to the circuit boards and relays of the guarded scanner are explained. Several tests were developed to evaluate the guarding effectiveness, including isolating sections of the guard circuit to create a potential drop between the main and guard circuits. Calibration of standard resistors using the guarded scanner has shown relative differences less than 1×10-6, 30×10-6, and 150×10-6 for measurements made with and without the guarded scanner at nominal resistances of 1, 10, and 100 GΩ, respectively. The substitution method was used to significantly reduce the relative differences between channels to less than 0.5×10-6, 3×10-6, and 30×10-6 for nominal resistances of 1, 10, and 100 GΩ, respectively. Applications for the guarded scanner in automated direct current measurement systems are presented.

  19. Fricção em braquetes gerada por fios de aço inoxidável, superelásticos com IonGuard e sem IonGuard Friction force on brackets generated by stainless steel wire and superelastic wires with and without IonGuard

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Campos Braga

    2011-08-01

    Full Text Available OBJETIVO: o objetivo deste estudo foi verificar a fricção no braquete (Roth, Composite, 10.17.005, 3,2mm, largura 0,022" x 0,030", Torque -2° e angulação +13°, Morelli®, Brasil, utilizando fios ortodônticos retangulares de 0,019" x 0,025" de aço inoxidável (Morelli®, Brasil e de níquel-titânio superelásticos Bioforce com IonGuard e sem IonGuard (Bioforce, GAC®, EUA. MÉTODOS: foram utilizados 24 conjuntos braquetes/segmento de fio, divididos em 3 grupos de acordo com o fio. Cada conjunto braquete/segmento de fio foi testado 3 vezes e obtida uma média. Os ensaios foram realizados em máquina universal de ensaios EMIC DL2000®. Os dados foram submetidos à Análise de Variância com significância de 95%. RESULTADOS: o fio retangular Bioforce com IonGuard apresentou fricção significativamente menor que o Bioforce sem IonGuard, porém sem diferença do fio de aço inoxidável. Entretanto, o coeficiente de variação dos fios Bioforce com e sem IonGuard foi menor que o do fio de aço inoxidável. CONCLUSÃO: os fios retangulares de 0,019" x 0,025" Bioforce com IonGuard apresentam menor fricção que o fio Bioforce sem IonGuard, sem diferença para o fio de aço inoxidável.OBJECTIVE: The aim of this study was to evaluate the friction forces on brackets (Roth, Composite, 10.17.005, 3.2 mm, width 0.022" x 0.030 ", Torque -2° and angulation +13°, Morelli®, Brazil, with stainless steel orthodontic rectangular wire (Morelli®, Brazil and nickel titanium superelastic Bioforce wires with and without IonGuard (Bioforce, GAC®, USA. MATERIAL AND METHODS: Twenty-four brackets/wire segment combinations were used, distributed into three groups according to the orthodontic wire. Each bracket/wire segment combination was tested three times. The tests were performed in a universal testing machine Emic DL2000®. The data was submitted to ANOVA one way followed by Tukey's post hoc test (p<0.05. RESULTS: The rectangular orthodontic Bioforce wire

  20. Ring Theory

    CERN Document Server

    Jara, Pascual; Torrecillas, Blas

    1988-01-01

    The papers in this proceedings volume are selected research papers in different areas of ring theory, including graded rings, differential operator rings, K-theory of noetherian rings, torsion theory, regular rings, cohomology of algebras, local cohomology of noncommutative rings. The book will be important for mathematicians active in research in ring theory.

  1. Marine Hydrokinetic Resource Assessment for Domestic Army, Air Force, and Coast Guard Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Robichaud, Robi J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Ingram, Michael [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2018-04-24

    NREL/DOE undertook a study for the US Army, Coast Guard and Air Force to investigate the potential for marine hydrokinetic (MHK) devices to meet the energy load at coastal bases in the future as MHK technology evolves. A wide range of data from tidal and wave, environmental, shipping, etc. databases were used to screen the DOD bases. A series of scoring algorithms were developed to facilitate site review to lead to eventual down select for more detailed, site specific bathymetric tidal resource evaluation. The Army's Camp Edwards, MA and the Coast Guard's Training Center Cape May, NJ (TRACEN Cape May) were selected and the Georgia Institute of Technology performed the analyses. An NREL/DOE MHK team visited the bases to further discuss with the base personnel MHK technology's potential for providing power to the bases in the future and frame the potential impact to existing power systems.

  2. Integrated Unit Deployments: Rethinking Air National Guard Fighter Mobilizations

    Science.gov (United States)

    2016-06-01

    participation in the homeland defense mission. But they emphasized that homeland defense would not become an exclusive ANG mission. Operation...station that can absorb pilots and maintainers left behind. Few Air National Guard squadrons enjoy this luxury . Only Air Guard squadrons that are part

  3. Group graded associated ideals with flat base change of rings and ...

    Indian Academy of Sciences (India)

    developed in [12] for G-associated ideals, that is, the behaviour of G-associated ideals. (AssG) with short exact sequences. Second, in §4 we consider the generalized notions of. G-associated prime ideals for not necessarily Noetherian rings and introduce strong Krull. G-associated ideals (AssSG) with flat base change of ...

  4. US Coast Guard Stations in Louisiana, Geographic NAD83, USCG [coast_guard_stations_USCG_1997

    Data.gov (United States)

    Louisiana Geographic Information Center — This is is a point dataset for the locations and attributes of eight US Coast Guard stations in Louisiana. The attributes include name, address, latitude (NAD27),...

  5. Evaluation of slim-edge, multi-guard, and punch-through-protection structures before and after proton irradiation

    Science.gov (United States)

    Mitsui, S.; Unno, Y.; Ikegami, Y.; Takubo, Y.; Terada, S.; Hara, K.; Takahashi, Y.; Jinnouchi, O.; Nagai, R.; Kishida, T.; Yorita, K.; Hanagaki, K.; Takashima, R.; Kamada, S.; Yamamura, K.

    2013-01-01

    Planar geometry silicon pixel and strip sensors for the high luminosity upgrade of the LHC (HL-LHC) require a high bias voltage of 1000 V in order to withstand a radiation damage caused by particle fluences of 1×1016 1 MeV neq/cm2 and 1×1015 1 MeV neq/cm2 for pixel and strip detectors, respectively. In order to minimize the inactive edge space that can withstand a bias voltage of 1000 V, edge regions susceptible to microdischarge (MD) should be carefully optimized. We fabricated diodes with various edge distances (slim-edge diodes) and with 1-3 multiple guard rings (multi-guard diodes). AC coupling insulators of strip sensors are vulnerable to sudden heavy charge deposition, such as an accidental beam splash, which may destroy the readout AC capacitors. Thus various types of punch-through-protection (PTP) structures were implemented in order to find the most effective structure to protect against heavy charge deposition. These samples were irradiated with 70 MeV protons at fluences of 5×1012 1 MeV neq/cm2-1×1016 1 MeV neq/cm2. Their performances were evaluated before and after irradiation in terms of an onset voltage of the MD, a turn-on voltage of the PTP, and PTP saturation resistance.

  6. Volunteers in the Danish Home Guard 2011

    DEFF Research Database (Denmark)

    Fridberg, Torben; Damgaard, Malene

    voluntary work than the population as a whole. The report also shows that one in three active members of the Home Guard would like to be deployed on international operations to support the armed forces. The young members are especially willing – and these members have increased in recent years. This report......This report describes the composition of the Home Guard’s volunteer members and their attitudes to and expectations for the Home Guard. A similar survey was carried out in 2007, and the present report therefore also examines the trends from 2007 to 2011. Among other things, the report shows...... that the voluntary members are a stable resource, as on average they have been members of the Home Guard for more than 24 years. There is a clear majority of men aged 25-50. Relatively many have vocational training, and many are employed in the private sector. Members are also relatively more active in other...

  7. Use of Head Guards in AIBA Boxing Tournaments-A Cross-Sectional Observational Study.

    Science.gov (United States)

    Loosemore, Michael P; Butler, Charles F; Khadri, Abdelhamid; McDonagh, David; Patel, Vimal A; Bailes, Julian E

    2017-01-01

    This study looks at the changes in injuries after the implementation of a new rule by the International Boxing Association (AIBA) to remove head guards from its competitions. A cross-sectional observational study performed prospectively. This brief report examines the removal of head guards in 2 different ways. The first was to examine the stoppages due to blows to the head by comparing World Series Boxing (WSB), without head guards, to other AIBA competitions with head guards. Secondly, we examined the last 3 world championships: 2009 and 2011 (with head guards) and 2013 (without head guards). World Series Boxing and AIBA world championship boxing. Boxers from WSB and AIBA world championships. The information was recorded by ringside medical physicians. Stoppages per 10 000 rounds; stoppages per 1000 hours. Both studies show that the number of stoppages due to head blows was significantly decreased without head guards. The studies also showed that there was a notable increase in cuts. Removing head guards may reduce the already small risk of acute brain injury in amateur boxing.

  8. Efficient Test Application for Core-Based Systems Using Twisted-Ring Counters

    OpenAIRE

    Anshuman Chandra; Krishnendu Chakrabarty; Mark C. Hansen

    2001-01-01

    We present novel test set encoding and pattern decompression methods for core-based systems. These are based on the use of twisted-ring counters and offer a number of important advantages–significant test compression (over 10X in many cases), less tester memory and reduced testing time, the ability to use a slow tester without compromising test quality or testing time, and no performance degradation for the core under test. Surprisingly, the encoded test sets obtained from partially-specified...

  9. The Impact of Excluding Food Guarding from a Standardized Behavioral Canine Assessment in Animal Shelters

    Directory of Open Access Journals (Sweden)

    Heather Mohan-Gibbons

    2018-02-01

    Full Text Available Many shelters euthanize or restrict adoptions for dogs that exhibit food guarding while in the animal shelter. However, previous research showed that only half the dogs exhibiting food guarding during an assessment food guard in the home. So, dogs are often misidentified as future food guarders during shelter assessments. We examined the impact of shelters omitting food guarding assessments. Nine shelters conducted a two-month baseline period of assessing for food guarding followed by a two-month investigative period during which they omitted the food guarding assessment. Dogs that guarded their food during a standardized assessment were less likely to be adopted, had a longer shelter stay, and were more likely to be euthanized. When the shelters stopped assessing for food guarding, there was no significant difference in the rate of returns of food guarding dogs, even though more dogs were adopted because fewer were identified with food guarding behavior. Additionally, the number of injuries to staff, volunteers, and adopters was low (104 incidents from a total of 14,180 dogs and did not change when the food guarding assessment was omitted. These results support a recommendation that shelters discontinue the food guarding assessment.

  10. Spatial-mode switchable ring fiber laser based on low mode-crosstalk all-fiber mode MUX/DEMUX

    Science.gov (United States)

    Ren, Fang; Yu, Jinyi; Wang, Jianping

    2018-05-01

    We report an all-fiber ring laser that emits linearly polarized (LP) modes based on the intracavity all-fiber mode multiplexer/demultiplexer (MUX/DEMUX). Multiple LP modes in ring fiber laser are generated by taking advantage of mode MUX/DEMUX. The all-fiber mode MUX/DEMUX are composed of cascaded mode-selective couplers (MSCs). The output lasing mode of the ring fiber laser can be switched among the three lowest-order LP modes by employing combination of a mode MUX and a simple N × 1 optical switch. The slope efficiencies, optical spectra and mode profiles are measured.

  11. 30 CFR 56.7013 - Covering or guarding drill holes.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Covering or guarding drill holes. 56.7013 Section 56.7013 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Rotary Jet Piercing Drilling § 56.7013 Covering or guarding drill holes. Drill holes large enough to...

  12. 30 CFR 57.7013 - Covering or guarding drill holes.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Covering or guarding drill holes. 57.7013 Section 57.7013 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... and Rotary Jet Piercing Drilling-Surface Only § 57.7013 Covering or guarding drill holes. Drill holes...

  13. A feasibility study of a neutrino source based on a muon storage ring

    CERN Document Server

    Finley, D

    2001-01-01

    We present the results of a study commissioned by the Fermilab Director on the feasibility of an intense neutrino source, based on a muon storage ring. Muon colliders have been discussed as an alternate route to very high-energy lepton colliders. As a by-product, such a collider would produce very intense neutrino beams because of the decaying muons circulating in the storage ring. In a dedicated storage ring, these neutrino beams could be produced in long straight sections which would point towards long, medium or short baseline detectors, opening up a whole new class of neutrino physics experiments because of the enormous neutrino flux that, in principle, could be achieved in such a facility as compared to more standard fixed target sources. Intense pion sources in combination with powerful emittance cooling strategies for the comparatively large muon emittance are necessary to make this type of neutrino source as well as a muon collider, feasible for a possible future high energy physics facility. The Neut...

  14. Manipulation of vortex rings for flow control

    International Nuclear Information System (INIS)

    Toyoda, Kuniaki; Hiramoto, Riho

    2009-01-01

    This paper reviews the dynamics of vortex rings and the control of flow by the manipulation of vortex rings. Vortex rings play key roles in many flows; hence, the understanding of the dynamics of vortex rings is crucial for scientists and engineers dealing with flow phenomena. We describe the structures and motions of vortex rings in circular and noncircular jets, which are typical examples of flows evolving into vortex rings. For circular jets the mechanism of evolving, merging and breakdown of vortex rings is described, and for noncircular jets the dynamics of three-dimensional deformation and interaction of noncircular vortex rings under the effect of self- and mutual induction is discussed. The application of vortex-ring manipulation to the control of various flows is reviewed with successful examples, based on the relationship between the vortex ring dynamics and the flow properties. (invited paper)

  15. Great Lakes Surface Ice Reports from U.S. Coast Guard

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data consist of ice observations from U.S. Coast Guard vessels operating on the Great Lakes, and from Coast Guard shore stations reported via teletype messages and...

  16. Process based model sheds light on climate sensitivity of Mediterranean tree-ring width

    Directory of Open Access Journals (Sweden)

    R. Touchan

    2012-03-01

    Full Text Available We use the process-based VS (Vaganov-Shashkin model to investigate whether a regional Pinus halepensis tree-ring chronology from Tunisia can be simulated as a function of climate alone by employing a biological model linking day length and daily temperature and precipitation (AD 1959–2004 from a climate station to ring-width variations. We check performance of the model on independent data by a validation exercise in which the model's parameters are tuned using data for 1982–2004 and the model is applied to generate tree-ring indices for 1959–1981. The validation exercise yields a highly significant positive correlation between the residual chronology and estimated growth curve (r=0.76 p<0.0001, n=23. The model shows that the average duration of the growing season is 191 days, with considerable variation from year to year. On average, soil moisture limits tree-ring growth for 128 days and temperature for 63 days. Model results depend on chosen values of parameters, in particular a parameter specifying a balance ratio between soil moisture and precipitation. Future work in the Mediterranean region should include multi-year natural experiments to verify patterns of cambial-growth variation suggested by the VS model.

  17. AlphaGUARD, the new reference for continuous radon monitoring in air, soil, gas, water and material; AlphaGUARD, die neue Referenz fuer die kontinuierliche Messung der Radonkonzentration in Luft, Boden, Wasser und Baumaterial

    Energy Technology Data Exchange (ETDEWEB)

    Roessler, F.; Buerkin, W. [Saphymo GmbH, Frankfurt am Main (Germany); Villert, J. [Bertin Technologies, Montigny (France)

    2016-07-01

    The company Saphymo GmbH has more than 25 years of experience in the field of radon measurement. More than 20 years ago Saphymo developed the professional and robust radon monitor AlphaGUARD, quickly recognized as a standard for reliable and continuous measurements of the radon concentration. Today AlphaGUARD is internationally established as the reference in radon measurement. Following up on this success story the new generation of AlphaGUARD can now be presented. Based on the excellent measurement characteristics of its predecessor the new AlphaGUARD combines the well-proven principle of the pulse ionisation chamber with new and additional features. The robust housing is oriented on the well-proven design of the predecessor and includes now an integrated flow controlled and powerful pump. The instrument can be operated in flow as well as in diffusion mode (without pump). Via the new large display and the intuitive menu navigation all measurement data can be retrieved. The presentation of time series in charts is possible as well as the parametrisation of the instrument. A wide range of accessories, developed in cooperation with various radon experts of universities and laboratories, enables the user a varied and flexible application of the AlphaGUARD: Measurement of the radon concentration in air (radon, thoron, radon progenies), in water (sampling and time resolved measurements) and in soil (soil gas measurements, exhalation measurements), emanation measurements from material, multi spot measurement, online measurement with remote data transmission via Ethernet/DSL, Bluetooth, Wi-Fi, GPRS/3G or satellite. Due to its high sensitivity and its fast and linear response over a large measuring range the AlphaGUARD is excellently suited for calibration laboratories. Furthermore the AlphaGUARD enables ideal prerequisites for field applications: robust housing for operations under harsh conditions, long battery life for the measurement at any location, low

  18. Line Heat-Source Guarded Hot Plate

    Data.gov (United States)

    Federal Laboratory Consortium — Description:The 1-meter guarded hot-plate apparatus measures thermal conductivity of building insulation. This facility provides for absolute measurement of thermal...

  19. Plasma-ring, fast-opening switch

    International Nuclear Information System (INIS)

    Hartman, C.W.; Eddleman, J.; Hammer, J.H.

    1986-01-01

    The authors discuss a fast-opening switch concept based on magnetically confined plasma rings, PROS (for Plasma Ring Opening Switch). In PROS, the plasma ring, confined by Bθ /sub and B/poloidal /sub fields of a compact torus, provide a low mass, localized conduction path between coaxial electrodes. To operate the switch, driver current is passed across the electrodes through the ring, storing inductive energy in external inductance and between the electrodes on the driver side of the ring. The ring is accelerated away from the driver by the field of the driver current and passes over a load gap transferring the current to the load. The authors distinguish two configurations in PROS, straight PROS where the electrodes are coaxial cylinders, and cone PROS with conical electrodes. In straight PROS ring acceleration takes place during the inductive store period as in foil switches, but with the localized ring providing the current path. Increased performance is predicted for the cone PROS (see figure) which employs compression of the ring in the cone during the inductive store period. Here, the B/θ /sub field of the driver forces the ring towards the apex of the cone but the force is in near balance with the opposing component of the radial equilibrium force of the ring along the cone. As a result, the ring undergoes a slow, quasistatic compression limited only by resistive decay of the ring field. Slow compression allows inductive storage with low-power drivers (homopoloar, magneto cumulative generators, high C-low V capacitor banks, etc.). Near the apex of the cone, near peak compression, the ring is allowed to enter a straight coaxial section where, because of low-mass, it rapidly accelerates to high velocity and crosses the load gap

  20. A metamaterial terahertz modulator based on complementary planar double-split-ring resonator

    Science.gov (United States)

    Wang, Chang-hui; Kuang, Deng-feng; Chang, Sheng-jiang; Lin, Lie

    2013-07-01

    A metamaterial based on complementary planar double-split-ring resonator (DSRR) structure is presented and demonstrated, which can optically tune the transmission of the terahertz (THz) wave. Unlike the traditional DSRR metamaterials, the DSRR discussed in this paper consists of two split rings connected by two bridges. Numerical simulations with the finite-difference time-domain (FDTD) method reveal that the transmission spectra of the original and the complementary metamaterials are both in good agreement with Babinet's principle. Then by increasing the carrier density of the intrinsic GaAs substrate, the magnetic response of the complementary special DSRR metamaterial can be weakened or even turned off. This metamaterial structure is promised to be a narrow-band THz modulator with response time of several nanoseconds.

  1. Classifications of Cohen-Macaulay modules - The base ring associated to a transversal polymatroid

    OpenAIRE

    Ştefan, Alin

    2008-01-01

    In this thesis, we focus on the study of the base rings associated to some transversal polymatroids. A transversal polymatroid is a special kind of discrete polymatroid. Discrete polymatroids were introduced by Herzog and Hibi \\cite{HH} in 2002.

  2. A multiple-orbit time-of-flight mass spectrometer based on a low energy electrostatic storage ring

    Science.gov (United States)

    Sullivan, M. R.; Spanjers, T. L.; Thorn, P. A.; Reddish, T. J.; Hammond, P.

    2012-11-01

    The results are presented for an electrostatic storage ring, consisting of two hemispherical deflector analyzers (HDA) connected by two separate sets of cylindrical lenses, used as a time-of-flight mass spectrometer. Based on the results of charged particle simulations and formal matrix model, the Ion Storage Ring is capable of operating with multiple stable orbits, for both single and multiply charged ions simultaneously.

  3. Guard cell zeaxanthin tracks photosynthetically active radiation and stomatal apertures in Vicia faba leaves

    International Nuclear Information System (INIS)

    Srivastava, A.; Zeiger, E.

    1995-01-01

    Zeaxanthin, antheraxanthin and violaxanthin concentrations in guard cells from sonicated abaxial epidermal peels of Vicia faba were measured from dawn to dusk, and compared with concentrations in mesophyll tissue of the same leaves. Measured changes in guard cell zeaxanthin and violaxanthin concentrations indicate that guard cells operate the xanthophyll cycle throughout the day. Mesophyll tissue had no detectable zeaxanthin at dawn, whereas guard cells had 30–50 mmol mol −1 chlorophyll a+b. On a chlorophyll basis, maximal zeaxanthin levels were 3–4 fold higher in guard cells than in mesophyll cells. Zeaxanthin concentrations tracked levels of photosynthetically active radiation (PAR) in both mesophyll and guard cells. In the mesophyll, most of the zeaxanthin changes occurred in mid-morning and mid-afternoon. In guard cells, zeaxanthin concentrations changed nearly linearly with PAR in the early morning and late afternoon, and closely tracked PAR levels throughout the day. Guard cell zeaxanthin concentrations were also closely correlated with stomatal apertures. The close relationship between zeaxanthin concentrations and PAR levels in guard cells indicates that zeaxanthin is well suited to function as a molecular photosensor in stomatal movements. (author)

  4. ASSOCIATIVE RINGS SOLVED AS LIE RINGS

    Directory of Open Access Journals (Sweden)

    M. B. Smirnov

    2011-01-01

    Full Text Available The paper has proved that an associative ring which is solvable of a n- class as a Lie ring has a nilpotent ideal of the nilpotent class not more than 3×10n–2  and a corresponding quotient ring satisfies an identity [[x1, x2, [x3, x4

  5. Galactic rings revisited - I. CVRHS classifications of 3962 ringed galaxies from the Galaxy Zoo 2 Database

    Science.gov (United States)

    Buta, Ronald J.

    2017-11-01

    Rings are important and characteristic features of disc-shaped galaxies. This paper is the first in a series that re-visits galactic rings with the goals of further understanding the nature of the features and for examining their role in the secular evolution of galaxy structure. The series begins with a new sample of 3962 galaxies drawn from the Galaxy Zoo 2 citizen science data base, selected because zoo volunteers recognized a ring-shaped pattern in the morphology as seen in Sloan Digital Sky Survey colour images. The galaxies are classified within the framework of the Comprehensive de Vaucouleurs revised Hubble-Sandage system. It is found that zoo volunteers cued on the same kinds of ring-like features that were recognized in the 1995 Catalogue of Southern Ringed Galaxies. This paper presents the full catalogue of morphological classifications, comparisons with other sources of classifications and some histograms designed mainly to highlight the content of the catalogue. The advantages of the sample are its large size and the generally good quality of the images; the main disadvantage is the low physical resolution that limits the detectability of linearly small rings such as nuclear rings. The catalogue includes mainly inner and outer disc rings and lenses. Cataclysmic (`encounter-driven') rings (such as ring and polar ring galaxies) are recognized in less than 1 per cent of the sample.

  6. U.S. Coast Guard (USCG) Districts

    Data.gov (United States)

    Department of Homeland Security — This layer is a polygonal dataset that represents land and maritime boundaries for each representative United States Coast Guard district, which includes district 1,...

  7. 49 CFR 1520.15 - SSI disclosed by TSA or the Coast Guard.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false SSI disclosed by TSA or the Coast Guard. 1520.15... PROTECTION OF SENSITIVE SECURITY INFORMATION § 1520.15 SSI disclosed by TSA or the Coast Guard. (a) In... available for public inspection or copying, nor does TSA or the Coast Guard release such records to persons...

  8. Ranking of tree-ring based temperature reconstructions of the past millennium

    Science.gov (United States)

    Esper, Jan; Krusic, Paul J.; Ljungqvist, Fredrik C.; Luterbacher, Jürg; Carrer, Marco; Cook, Ed; Davi, Nicole K.; Hartl-Meier, Claudia; Kirdyanov, Alexander; Konter, Oliver; Myglan, Vladimir; Timonen, Mauri; Treydte, Kerstin; Trouet, Valerie; Villalba, Ricardo; Yang, Bao; Büntgen, Ulf

    2016-08-01

    Tree-ring chronologies are widely used to reconstruct high-to low-frequency variations in growing season temperatures over centuries to millennia. The relevance of these timeseries in large-scale climate reconstructions is often determined by the strength of their correlation against instrumental temperature data. However, this single criterion ignores several important quantitative and qualitative characteristics of tree-ring chronologies. Those characteristics are (i) data homogeneity, (ii) sample replication, (iii) growth coherence, (iv) chronology development, and (v) climate signal including the correlation with instrumental data. Based on these 5 characteristics, a reconstruction-scoring scheme is proposed and applied to 39 published, millennial-length temperature reconstructions from Asia, Europe, North America, and the Southern Hemisphere. Results reveal no reconstruction scores highest in every category and each has their own strengths and weaknesses. Reconstructions that perform better overall include N-Scan and Finland from Europe, E-Canada from North America, Yamal and Dzhelo from Asia. Reconstructions performing less well include W-Himalaya and Karakorum from Asia, Tatra and S-Finland from Europe, and Great Basin from North America. By providing a comprehensive set of criteria to evaluate tree-ring chronologies we hope to improve the development of large-scale temperature reconstructions spanning the past millennium. All reconstructions and their corresponding scores are provided at http://www.blogs.uni-mainz.de/fb09climatology.

  9. 30 CFR 57.12023 - Guarding electrical connections and resistor grids.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Guarding electrical connections and resistor... NONMETAL MINES Electricity Surface and Underground § 57.12023 Guarding electrical connections and resistor grids. Electrical connections and resistor grids that are difficult or impractical to insulate shall be...

  10. Specific recognition of reproductive parasite workers by nest-entrance guards in the bumble bee Bombus terrestris.

    Science.gov (United States)

    Blacher, Pierre; Boreggio, Laurie; Leroy, Chloé; Devienne, Paul; Châline, Nicolas; Chameron, Stéphane

    2013-12-10

    The impact of social parasites on their hosts' fitness is a strong selective pressure that can lead to the evolution of adapted defence strategies. Guarding the nest to prevent the intrusion of parasites is a widespread response of host species. If absolute rejection of strangers provides the best protection against parasites, more fine-tuned strategies can prove more adaptive. Guarding is indeed costly and not all strangers constitute a real threat. That is particularly true for worker reproductive parasitism in social insects since only a fraction of non-nestmate visitors, the fertile ones, can readily engage in parasitic reproduction. Guards should thus be more restrictive towards fertile than sterile non-nestmate workers. We here tested this hypothesis by examining the reaction of nest-entrance guards towards nestmate and non-nestmate workers with varying fertility levels in the bumble bee Bombus terrestris. Because social recognition in social insects mainly relies on cuticular lipids (CLs), chemical analysis was also conducted to examine whether workers' CLs could convey the relevant information upon which guards could base their decision. We thus aimed to determine whether an adapted defensive strategy to worker reproductive parasitism has evolved in B. terrestris colonies. Chemical analysis revealed that the cuticular chemical profiles of workers encode information about both their colony membership and their current fertility, therefore providing potential recognition cues for a suitable adjustment of the guards' defensive decisions. We found that guards were similarly tolerant towards sterile non-nestmate workers than towards nestmate workers. However, as predicted, guards responded more aggressively towards fertile non-nestmates. Our results show that B. terrestris guards discriminate non-nestmates that differ in their reproductive potential and respond more strongly to the individuals that are a greatest threat for the colony. Cuticular hydrocarbons are

  11. Nitric oxide in guard cells as an important secondary messenger during stomatal closure

    Directory of Open Access Journals (Sweden)

    Gunja eGayatri

    2013-10-01

    Full Text Available he modulation of guard cell function is the basis of stomatal closure, essential for optimizing water use and CO2 uptake by leaves. Nitric oxide (NO in guard cells plays a very important role as a secondary messenger during stomatal closure induced by effectors, including hormones. For example, exposure to abscisic acid (ABA triggers a marked increase in NO of guard cells, well before stomatal closure. In guard cells of multiple species, like Arabidopsis, Vicia and pea, exposure to ABA or methyl jasmonate or even microbial elicitors (e.g. chitosan induces production of NO as well as reactive oxygen species (ROS. The role of NO in stomatal closure has been confirmed by using NO donors (e.g. SNP and NO scavengers (like cPTIO and inhibitors of NOS (L-NAME or NR (tungstate. Two enzymes: a L-NAME-sensitive, nitric oxide synthase (NOS-like enzyme and a tungstate-sensitive nitrate reductase (NR, can mediate ABA-induced NO rise in guard cells. However, the existence of true NOS in plant tissues and its role in guard cell NO-production are still a matter of intense debate. Guard cell signal transduction leading to stomatal closure involves the participation of several components, besides NO, such as cytosolic pH, ROS, free Ca2+ and phospholipids. Use of fluorescent dyes has revealed that the rise in NO of guard cells occurs after the increase in cytoplasmic pH and ROS. The rise in NO causes an elevation in cytosolic free Ca2+ and promotes the efflux of cations as well as anions from guard cells. Stomatal guard cells have become a model system to study the signalling cascade mechanisms in plants, particularly with NO as a dominant component. The interrelationships and interactions of NO with cytosolic pH, ROS, and free Ca2+ are quite complex and need further detailed examination. While assessing critically the available literature, the present review projects possible areas of further work related to NO-action in stomatal guard cells.

  12. Mapping Ring Particle Cooling across Saturn's Rings with Cassini CIRS

    Science.gov (United States)

    Brooks, Shawn M.; Spilker, L. J.; Edgington, S. G.; Pilorz, S. H.; Deau, E.

    2010-10-01

    Previous studies have shown that the rings' thermal inertia, a measure of their response to changes in the thermal environment, varies from ring to ring. Thermal inertia can provide insight into the physical structure of Saturn's ring particles and their regoliths. Low thermal inertia and quick temperature responses are suggestive of ring particles that have more porous or fluffy regoliths or that are riddled with cracks. Solid, coherent particles can be expected to have higher thermal inertias (Ferrari et al. 2005). Cassini's Composite Infrared Spectrometer has recorded millions of spectra of Saturn's rings since its arrival at Saturn in 2004 (personal communication, M. Segura). CIRS records far infrared radiation between 10 and 600 cm-1 (16.7 and 1000 µm) at focal plane 1 (FP1), which has a field of view of 3.9 mrad. Thermal emission from Saturn's rings peaks in this wavelength range. FP1 spectra can be used to infer ring temperatures. By tracking how ring temperatures vary, we can determine the thermal inertia of the rings. In this work we focus on CIRS observations of the shadowed portion of Saturn's rings. The thermal budget of the rings is dominated by the solar radiation absorbed by its constituent particles. When ring particles enter Saturn's shadow this source of energy is abruptly cut off. As a result, ring particles cool as they traverse Saturn's shadow. From these shadow observations we can create cooling curves at specific locations across the rings. We will show that the rings' cooling curves and thus their thermal inertia vary not only from ring to ring, but by location within the individual rings. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Copyright 2010 California Institute of Technology. Government sponsorship acknowledged.

  13. Compact high-efficiency vortex beam emitter based on a silicon photonics micro-ring

    DEFF Research Database (Denmark)

    Li, Shimao; Ding, Yunhong; Guan, Xiaowei

    2018-01-01

    Photonic integrated devices that emit vortex beam carrying orbital angular momentum are becoming key components for multiple applications. Here we propose and demonstrate a high-efficiency vortex beam emitter based on a silicon micro-ring resonator integrated with a metal mirror. Such a compact...

  14. 76 FR 17782 - Protection for Whistleblowers in the Coast Guard

    Science.gov (United States)

    2011-03-31

    ... ``Keyword'' box, and then clicking ``Search.'' FOR FURTHER INFORMATION CONTACT: If you have questions on..., telephone 202-372-3777, e-mail [email protected] . If you have questions on viewing or submitting... Protection for Whistleblowers in the Coast Guard AGENCY: Coast Guard, DHS. ACTION: Direct final rule...

  15. A simple self-restored fiber Bragg grating (FBG)-based passive sensing ring network

    International Nuclear Information System (INIS)

    Yeh, Chien-Hung; Chow, Chi-Wai; Wang, Chia-Husan; Shih, Fu-Yuan; Wu, Yu-Fu; Chi, Sien

    2009-01-01

    In this investigation, we propose and experimentally investigate a simple self-restored fiber Bragg grating (FBG)-based sensor ring system. This proposed multi-ring passive sensing architecture does not require active components in the network. In this experiment, the network survivability and capacity for the multi-point sensor systems are also enhanced. Besides, the tunable laser source (TLS) is adopted in a central office (CO) for FBG sensing. The survivability of an eight-point FBG sensor is examined and analyzed. It is cost effective since the sensing system is entirely centralized in the CO. Experimental results show that the proposed system can enhance the reliability of the FBG sensing network for large-scale and multi-point architecture. (rapid communication)

  16. Synthesis of the EF-ring of ciguatoxin 3C based on the [2,3]-Wittig rearrangement and ring-closing olefin metathesis.

    Science.gov (United States)

    Goto, Akiyoshi; Fujiwara, Kenshu; Kawai, Ayako; Kawai, Hidetoshi; Suzuki, Takanori

    2007-12-20

    The EF-ring segment of ciguatoxin 3C, a causative toxin of ciguatera fish poisoning, was synthesized in three major steps: 1,4-addition for the C20O-C27 bond connection, chirality transferring anti selective [2,3]-Wittig rearrangement for the construction of the anti-2-hydroxyalkyl ether part, and ring-closing olefin metathesis for the F-ring formation.

  17. 77 FR 16929 - Safety Zones; Fireworks Displays within the Fifth Coast Guard District

    Science.gov (United States)

    2012-03-23

    ...-AA00 Safety Zones; Fireworks Displays within the Fifth Coast Guard District AGENCY: Coast Guard, DHS... for fireworks displays at various locations within the geographic boundary of the Fifth Coast Guard... by fireworks displays. Entry into or movement within these zones during the enforcement periods is...

  18. United States Coast Guard: Officer Corps Military Professional Development Program

    Science.gov (United States)

    2011-06-10

    captain relieved of command after viewing porn on computer,‖ 10 July 2010, http://www.thenewstribune.com/2010/07/ 10/1259108/portland-coast-guard...Coast Guard captain relieved of command after viewing porn on computer,‖ 10 July 2010. http://www.thenewstribune.com/2010/07/ 10/1259108/portland

  19. 29 CFR Appendix B to Subpart B of... - Reprint of U.S. Coast Guard Regulations Referenced in Subpart B, for Determination of Coast Guard...

    Science.gov (United States)

    2010-07-01

    ... Subpart B, for Determination of Coast Guard Authorized Persons B Appendix B to Subpart B of Part 1915... Enclosed Spaces and Other Dangerous Atmospheres in Shipyard Employment Pt. 1915, Subpt. B, App. B Appendix B to Subpart B of Part 1915—Reprint of U.S. Coast Guard Regulations Referenced in Subpart B, for...

  20. RF-to-RF Characterization of a Phased Array Receive Antenna Steering System Using a Novel Ring Resonator-Based Integrated Photonic Beamformer

    NARCIS (Netherlands)

    Zhuang, L.; Burla, M.; Roeloffzen, C.G.H.; Meijerink, Arjan; Marpaung, D.A.I.; Khan, M.R.H.; van Etten, Wim; Leinse, Arne; Hoekman, M.; Heideman, Rene

    2009-01-01

    A novel ring resonator-based photonic beamformer has been developed for continuous and squint-free control of the reception angle of broadband phased array antenna systems. The core of the system is a ring resonator based optical beamforming network (OBFN) used for delay synchronization and coherent

  1. Microwave-assisted cationic ring-opening polymerization of a soy-based 2-oxazoline monomer

    NARCIS (Netherlands)

    Hoogenboom, R.; Wiesbrock, F.D.; Schubert, U.S.

    2005-01-01

    The microwave-assisted cationic ring-opening polymn. of a soy based 2-oxazoline monomer (SoyOx) is described. The microwave irradn. provides more efficient heating when compared to conventional heating and, in addn., the SoyOx was prepd. starting from a sustainable resource (soy beans). The

  2. Development of a circular shape Si-PM-based detector ring for breast-dedicated PET system

    Science.gov (United States)

    Nakanishi, Kouhei; Yamamoto, Seiichi; Watabe, Hiroshi; Abe, Shinji; Fujita, Naotoshi; Kato, Katsuhiko

    2018-02-01

    In clinical situations, various breast-dedicated positron emission tomography (PET) systems have been used. However, clinical breast-dedicated PET systems have polygonal detector ring. Polygonal detector ring sometimes causes image artifact, so complicated reconstruction algorithm is needed to reduce artifact. Consequently, we developed a circular detector ring for breast-dedicated PET to obtain images without artifact using a simple reconstruction algorithm. We used Lu1.9Gd0.1SiO5 (LGSO) scintillator block which was made of 1.5 x 1.9 x 15 mm pixels that were arranged in an 8 x 24 matrix. As photodetectors, we used silicon photomultiplier (Si-PM) arrays whose channel size was 3 x 3 mm. A detector unit was composed of four scintillator blocks, 16 Si-PM arrays and a light guide. The developed detector unit had angled configuration since the light guide was bending. A detector unit had three gaps with an angle of 5.625° between scintillator blocks. With these configurations, we could arrange 64 scintillator blocks in nearly circular shape (regular 64-sided polygon) using 16 detector units. The use of the smaller number of detector units could reduce the size of the front-end electronics circuits. The inner diameter of the developed detector ring was 260 mm. This size was similar to those of brain PET systems, so our breast-dedicated PET detector ring can measure not only breast but also brain. Measured radial, tangential and axial spatial resolution of the detector ring reconstructed by the filtered back-projection (FBP) algorithm were 2.1 mm FWHM, 2.0 mm FWHM and 1.7 mm FWHM at center of field of view (FOV), respectively. The sensitivity was 2.0% at center of the axial FOV. With the developed detector ring, we could obtain high resolution image of the breast phantom and the brain phantom. We conclude that our developed Si-PM-based detector ring is promising for a high resolution breast-dedicated PET system that can also be used for brain PET system.

  3. Triangulating and guarding realistic polygons

    NARCIS (Netherlands)

    Aloupis, G.; Bose, P.; Dujmovic, V.; Gray, C.M.; Langerman, S.; Speckmann, B.

    2014-01-01

    We propose a new model of realistic input: k-guardable objects. An object is k-guardable if its boundary can be seen by k guards. We show that k-guardable polygons generalize two previously identified classes of realistic input. Following this, we give two simple algorithms for triangulating

  4. 29 CFR 1915.73 - Guarding of deck openings and edges.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Guarding of deck openings and edges. 1915.73 Section 1915.73 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION..., Ladders and Other Working Surfaces § 1915.73 Guarding of deck openings and edges. (a) The provisions of...

  5. Computerspil og læring

    DEFF Research Database (Denmark)

    Larsen, Lasse Juel

    2015-01-01

    Game-based learning og gamification er ord, der ofte optræder i forbindelse med computerspil og læring. Denne artikel vil analytisk undersøge, hvordan computerspil og læring går i forbindelse med hinanden. Artikel tager afsæt i Gregory Batesons læringsteori og læser denne igennem det kommercielle...

  6. Stomatal Function Requires Pectin De-methyl-esterification of the Guard Cell Wall.

    Science.gov (United States)

    Amsbury, Sam; Hunt, Lee; Elhaddad, Nagat; Baillie, Alice; Lundgren, Marjorie; Verhertbruggen, Yves; Scheller, Henrik V; Knox, J Paul; Fleming, Andrew J; Gray, Julie E

    2016-11-07

    Stomatal opening and closure depends on changes in turgor pressure acting within guard cells to alter cell shape [1]. The extent of these shape changes is limited by the mechanical properties of the cells, which will be largely dependent on the structure of the cell walls. Although it has long been observed that guard cells are anisotropic due to differential thickening and the orientation of cellulose microfibrils [2], our understanding of the composition of the cell wall that allows them to undergo repeated swelling and deflation remains surprisingly poor. Here, we show that the walls of guard cells are rich in un-esterified pectins. We identify a pectin methylesterase gene, PME6, which is highly expressed in guard cells and required for stomatal function. pme6-1 mutant guard cells have walls enriched in methyl-esterified pectin and show a decreased dynamic range in response to triggers of stomatal opening/closure, including elevated osmoticum, suggesting that abrogation of stomatal function reflects a mechanical change in the guard cell wall. Altered stomatal function leads to increased conductance and evaporative cooling, as well as decreased plant growth. The growth defect of the pme6-1 mutant is rescued by maintaining the plants in elevated CO 2 , substantiating gas exchange analyses, indicating that the mutant stomata can bestow an improved assimilation rate. Restoration of PME6 rescues guard cell wall pectin methyl-esterification status, stomatal function, and plant growth. Our results establish a link between gene expression in guard cells and their cell wall properties, with a corresponding effect on stomatal function and plant physiology. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Work-related violence against security guards--who is most at risk?

    Science.gov (United States)

    Leino, Tuula; Selin, Risto; Summala, Heikki; Virtanen, Marianna

    2011-01-01

    Studies on violence in the work of security guards are largely lacking. This study is unique in that it focuses on security guards (n=1,010) in Finland, and assesses the different forms, prevalence, and risk factors of the work-related violence they often face. Information to a survey instrument was obtained by first interviewing 30 volunteers. Then we made a cross-sectional mailed survey that was sent to a randomized group of 2,000 security guards. The response rate was 52. We found the prevalence of verbal aggression, threats of assault, and physical acts against security guards at least once a month to be 39%, 19%, and 15% respectively. As regards risk factors and who is most at risk, our results show that male gender, young age, low work experience, late working hours, and time pressure were associated with all three forms of work-related violence. Unlike other forms of violence, verbal aggression was highly prevalent outside the metropolitan area and directed towards both more and less experienced security guards. In prevention policies for violence, it is important to identify high-risk groups such as those who have less work experience.

  8. Carbonic anhydrases are upstream regulators of CO2-controlled stomatal movements in guard cells

    KAUST Repository

    Hu, Honghong; Boisson-Dernier, Auré lien; Israelsson-Nordströ m, Maria; Bö hmer, Maik; Xue, Shaowu; Ries, Amber; Godoski, Jan; Kuhn, Josef M.; Schroeder, Julian I.

    2009-01-01

    photosynthesis and can function in guard cells. Furthermore, guard cell betaca-overexpressing plants exhibit instantaneous enhanced water use efficiency. Guard cell expression of mammalian alphaCAII complements the reduced sensitivity of ca1 ca4 plants, showing

  9. Triangulating and guarding realistic polygons

    NARCIS (Netherlands)

    Aloupis, G.; Bose, P.; Dujmovic, V.; Gray, C.M.; Langerman, S.; Speckmann, B.

    2008-01-01

    We propose a new model of realistic input: k-guardable objects. An object is k-guardable if its boundary can be seen by k guards in the interior of the object. In this abstract, we describe a simple algorithm for triangulating k-guardable polygons. Our algorithm, which is easily implementable, takes

  10. Nitric Oxide (NO) Measurements in Stomatal Guard Cells.

    Science.gov (United States)

    Agurla, Srinivas; Gayatri, Gunja; Raghavendra, Agepati S

    2016-01-01

    The quantitative measurement of nitric oxide (NO) in plant cells acquired great importance, in view of the multifaceted function and involvement of NO as a signal in various plant processes. Monitoring of NO in guard cells is quite simple because of the large size of guard cells and ease of observing the detached epidermis under microscope. Stomatal guard cells therefore provide an excellent model system to study the components of signal transduction. The levels and functions of NO in relation to stomatal closure can be monitored, with the help of an inverted fluorescence or confocal microscope. We can measure the NO in guard cells by using flouroprobes like 4,5-diamino fluorescein diacetate (DAF-2DA). This fluorescent dye, DAF-2DA, is cell permeable and after entry into the cell, the diacetate group is removed by the cellular esterases. The resulting DAF-2 form is membrane impermeable and reacts with NO to generate the highly fluorescent triazole (DAF-2T), with excitation and emission wavelengths of 488 and 530 nm, respectively. If time-course measurements are needed, the epidermis can be adhered to a cover-glass or glass slide and left in a small petri dishes. Fluorescence can then be monitored at required time intervals; with a precaution that excitation is done minimally, only when a fluorescent image is acquired. The present method description is for the epidermis of Arabidopsis thaliana and Pisum sativum and should work with most of the other dicotyledonous plants.

  11. Optical Fiber Sensors Based on Fiber Ring Laser Demodulation Technology.

    Science.gov (United States)

    Xie, Wen-Ge; Zhang, Ya-Nan; Wang, Peng-Zhao; Wang, Jian-Zhang

    2018-02-08

    A review for optical fiber sensors based on fiber ring laser (FRL) demodulation technology is presented. The review focuses on the principles, main structures, and the sensing performances of different kinds of optical fiber sensors based on FRLs. First of all, the theory background of the sensors has been discussed. Secondly, four different types of sensors are described and compared, which includes Mach-Zehnder interferometer (MZI) typed sensors, Fabry-Perot interferometer (FPI) typed sensors, Sagnac typed sensors, and fiber Bragg grating (FBG) typed sensors. Typical studies and main properties of each type of sensors are presented. Thirdly, a comparison of different types of sensors are made. Finally, the existing problems and future research directions are pointed out and analyzed.

  12. An Anonymous Access Authentication Scheme Based on Proxy Ring Signature for CPS-WMNs

    Directory of Open Access Journals (Sweden)

    Tianhan Gao

    2017-01-01

    Full Text Available Access security and privacy have become a bottleneck for the popularization of future Cyber-Physical System (CPS networks. Furthermore, users’ need for privacy-preserved access during movement procedure is more urgent. To address the anonymous access authentication issue for CPS Wireless Mesh Network (CPS-WMN, a novel anonymous access authentication scheme based on proxy ring signature is proposed. A hierarchical authentication architecture is presented first. The scheme is then achieved from the aspect of intergroup and intragroup anonymous mutual authentication through proxy ring signature mechanism and certificateless signature mechanism, respectively. We present a formal security proof of the proposed protocol with SVO logic. The simulation and performance analysis demonstrate that the proposed scheme owns higher efficiency and adaptability than the typical one.

  13. Relational Reasoning for Markov Chains in a Probabilistic Guarded Lambda Calculus

    DEFF Research Database (Denmark)

    Aguirre, Alejandro; Barthe, Gilles; Birkedal, Lars

    2018-01-01

    We extend the simply-typed guarded $\\lambda$-calculus with discrete probabilities and endow it with a program logic for reasoning about relational properties of guarded probabilistic computations. This provides a framework for programming and reasoning about infinite stochastic processes like...

  14. Radar imaging of Saturn's rings

    Science.gov (United States)

    Nicholson, Philip D.; French, Richard G.; Campbell, Donald B.; Margot, Jean-Luc; Nolan, Michael C.; Black, Gregory J.; Salo, Heikki J.

    2005-09-01

    We present delay-Doppler images of Saturn's rings based on radar observations made at Arecibo Observatory between 1999 and 2003, at a wavelength of 12.6 cm and at ring opening angles of 20.1°⩽|B|⩽26.7°. The average radar cross-section of the A ring is ˜77% relative to that of the B ring, while a stringent upper limit of 3% is placed on the cross-section of the C ring and 9% on that of the Cassini Division. These results are consistent with those obtained by Ostro et al. [1982, Icarus 49, 367-381] from radar observations at |B|=21.4°, but provide higher resolution maps of the rings' reflectivity profile. The average cross-section of the A and B rings, normalized by their projected unblocked area, is found to have decreased from 1.25±0.31 to 0.74±0.19 as the rings have opened up, while the circular polarization ratio has increased from 0.64±0.06 to 0.77±0.06. The steep decrease in cross-section is at variance with previous radar measurements [Ostro et al., 1980, Icarus 41, 381-388], and neither this nor the polarization variations are easily understood within the framework of either classical, many-particle-thick or monolayer ring models. One possible explanation involves vertical size segregation in the rings, whereby observations at larger elevation angles which see deeper into the rings preferentially see the larger particles concentrated near the rings' mid-plane. These larger particles may be less reflective and/or rougher and thus more depolarizing than the smaller ones. Images from all four years show a strong m=2 azimuthal asymmetry in the reflectivity of the A ring, with an amplitude of ±20% and minima at longitudes of 67±4° and 247±4° from the sub-Earth point. We attribute the asymmetry to the presence of gravitational wakes in the A ring as invoked by Colombo et al. [1976, Nature 264, 344-345] to explain the similar asymmetry long seen at optical wavelengths. A simple radiative transfer model suggests that the enhancement of the azimuthal

  15. Implementing Strategy in a Budget: A Model of the Coast Guard Reserve

    OpenAIRE

    Bromund, Carl Douglas

    1990-01-01

    Approved for public release; distribution is unlimited. This thesis discusses the managment strategy of the Coast Guard Reserve; it examines the formulation and implmentation of strateqy. A model to develop and implement strategy is proposed, which defines the role of the budget in this strategic management process. The recent strategy of the Coast Guard Reserve is analyzed using this model.. This analysis seems to indicate that the Coast Guard Reserve had no explicit strate...

  16. Environmental Service and Outdoor Adventure as a Context for Positive Youth Development: An Evaluation of the Crow River Trail Guards Program

    Directory of Open Access Journals (Sweden)

    Julie Ernst

    2013-06-01

    Full Text Available Trail Guards, a community-based organization in Minnesota, offers youth the opportunity to participate in park/trail maintenance and enhancement projects. Through these environmental service projects, Trail Guards seeks to foster the following developmental outcomes in youth participants: self-awareness of skills and strengths; self-worth; personal and social self-efficacy; sense of belonging and acceptance; team work and cooperation skills; and a sense of community responsibility. Trail Guards ultimately aims for youth to transfer these skills and socially appropriate behaviors to settings and activities beyond Trail Guards and to participate in the community in other positive ways. A program evaluation indicated Trail Guards seems to be achieving these youth development outcomes, and that the success of the program may be attributed to the program leader serving as a positive adult role model and providing a safe and caring environment, as well as to community involvement. Implications are discussed.

  17. AlphaGUARD, the new reference for continuous radon monitoring in air, soil, gas, water and material

    International Nuclear Information System (INIS)

    Roessler, F.; Buerkin, W.; Villert, J.

    2016-01-01

    The company Saphymo GmbH has more than 25 years of experience in the field of radon measurement. More than 20 years ago Saphymo developed the professional and robust radon monitor AlphaGUARD, quickly recognized as a standard for reliable and continuous measurements of the radon concentration. Today AlphaGUARD is internationally established as the reference in radon measurement. Following up on this success story the new generation of AlphaGUARD can now be presented. Based on the excellent measurement characteristics of its predecessor the new AlphaGUARD combines the well-proven principle of the pulse ionisation chamber with new and additional features. The robust housing is oriented on the well-proven design of the predecessor and includes now an integrated flow controlled and powerful pump. The instrument can be operated in flow as well as in diffusion mode (without pump). Via the new large display and the intuitive menu navigation all measurement data can be retrieved. The presentation of time series in charts is possible as well as the parametrisation of the instrument. A wide range of accessories, developed in cooperation with various radon experts of universities and laboratories, enables the user a varied and flexible application of the AlphaGUARD: Measurement of the radon concentration in air (radon, thoron, radon progenies), in water (sampling and time resolved measurements) and in soil (soil gas measurements, exhalation measurements), emanation measurements from material, multi spot measurement, online measurement with remote data transmission via Ethernet/DSL, Bluetooth, Wi-Fi, GPRS/3G or satellite. Due to its high sensitivity and its fast and linear response over a large measuring range the AlphaGUARD is excellently suited for calibration laboratories. Furthermore the AlphaGUARD enables ideal prerequisites for field applications: robust housing for operations under harsh conditions, long battery life for the measurement at any location, low

  18. Automated intracranial pressure-controlled cerebrospinal fluid external drainage with LiquoGuard.

    Science.gov (United States)

    Linsler, Stefan; Schmidtke, Mareike; Steudel, Wolf Ingo; Kiefer, Michael; Oertel, Joachim

    2013-08-01

    LiquoGuard is a new device for intracranial pressure (ICP)-controlled drainage of cerebrospinal fluid (CSF). This present study evaluates the accuracy of ICP measurement via the LiquoGuard device in comparison with Spiegelberg. Thus, we compared data ascertained from simultaneous measurement of ICP using tip-transducer and tip-sensor devices. A total of 1,764 monitoring hours in 15 patients (range, 52-219 h) were analysed. All patients received an intraventricular Spiegelberg III probe with the drainage catheter connected to the LiquoGuard system. ICP reading of both devices was performed on an hourly basis. Statistical analysis was done by applying Pearson correlation and Wilcoxon-matched pair test (p drainage. However, LiquoGuard tends to provide misleading results in slit ventricles. Thus, before these drawbacks are further analysed, the authors recommend additional ICP measurement with internal tip-sensor devices to avoid dangerous erroneous interpretation of ICP data.

  19. Quantitative Reconstruction of Sulfur Deposition Using a Mixing Model Based on Sulfur Isotope Ratios in Tree Rings.

    Science.gov (United States)

    Ishida, Takuya; Tayasu, Ichiro; Takenaka, Chisato

    2015-11-01

    Quantification of sulfur (S) deposition is critical to deciphering the environmental archive of S in terrestrial ecosystems. Here we propose a mixing model that quantifies S deposition based on the S isotope ratio (δS) in tree rings. We collected samples from Japanese cedar ( D. Don) stumps from two sites: one near Yokkaichi City (YOK), which is well known for having the heaviest S air pollution in the world, and one at Inabu-cho (INA) in central Japan, which has been much less affected by air pollution. The δS profiles at both sites are consistent with S air pollution and contributions of anthropogenic S. The minimum value in YOK is lower than the δS values of anthropogenic S or any other possible source. Because the δS in the tree rings is affected by fractionation in the forest ecosystems, we used a mixing model to account for the isotope effects and to distinguish the sources of S. Based on the model results, we infer that the peak of S emissions at YOK occurred sometime between the late 1960s and early 1970s (489 mmol m yr). This estimated value is comparable with the highest reported values in Europe. This is the first quantitative estimate of anthropogenic input of S in forest systems based on δS in tree rings. Our results suggest that tree ring data can be used when monitoring stations of atmospheric S are lacking and that estimates of S deposition using δS in tree rings will advance our understanding of the local-scale S dynamics and the effect of human activities on it. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  20. Black rings

    International Nuclear Information System (INIS)

    Emparan, Roberto; Reall, Harvey S

    2006-01-01

    A black ring is a five-dimensional black hole with an event horizon of topology S 1 x S 2 . We provide an introduction to the description of black rings in general relativity and string theory. Novel aspects of the presentation include a new approach to constructing black ring coordinates and a critical review of black ring microscopics. (topical review)

  1. The Storage Ring Proton EDM Experiment

    Science.gov (United States)

    Semertzidis, Yannis; Storage Ring Proton EDM Collaboration

    2014-09-01

    The storage ring pEDM experiment utilizes an all-electric storage ring to store ~1011 longitudinally polarized protons simultaneously in clock-wise and counter-clock-wise directions for 103 seconds. The radial E-field acts on the proton EDM for the duration of the storage time to precess its spin in the vertical plane. The ring lattice is optimized to reduce intra-beam scattering, increase the statistical sensitivity and reduce the systematic errors of the method. The main systematic error is a net radial B-field integrated around the ring causing an EDM-like vertical spin precession. The counter-rotating beams sense this integrated field and are vertically shifted by an amount, which depends on the strength of the vertical focusing in the ring, thus creating a radial B-field. Modulating the vertical focusing at 10 kHz makes possible the detection of this radial B-field by a SQUID-magnetometer (SQUID-based BPM). For a total number of n SQUID-based BPMs distributed around the ring the effectiveness of the method is limited to the N = n /2 harmonic of the background radial B-field due to the Nyquist sampling theorem limit. This limitation establishes the requirement to reduce the maximum radial B-field to 0.1-1 nT everywhere around the ring by layers of mu-metal and aluminum vacuum tube. The metho's sensitivity is 10-29 e .cm , more than three orders of magnitude better than the present neutron EDM experimental limit, making it sensitive to SUSY-like new physics mass scale up to 300 TeV.

  2. Infrared Spectroscopy Beamline Based on a Tabletop Storage Ring

    OpenAIRE

    Haque, Md. Monirul; Moon, Ahsa; Yamada, Hironari

    2012-01-01

    An optical beamline dedicated to the infrared (IR) spectroscopy has been constructed at MIRRORCLE, a tabletop storage ring. The beamline has been designed for the use of infrared synchrotron radiation (IRSR) emitted from a bending magnet of 156 mm bending radius with the acceptance angle of 355(H) × 138(V) mrad to obtain high flux. The IR emission is forced by an exactly circular optics, named photon storage ring (PhSR), placed around the electron orbit and is collected by a “magic mirror” as...

  3. Investigation of bearing inner ring-cage thermal characteristics based on CdTe quantum dots fluorescence thermometry

    International Nuclear Information System (INIS)

    Yan, Ke; Yan, Bei; Li, Ben Q.; Hong, Jun

    2017-01-01

    Highlights: • A novel method for bearing inner ring/cage thermal monitoring was first presented. • Temperature rise of bearing inner ring in real work condition was obtained. • The rotation speed (6000 r/min) measured here is much higher than all the existing methods. - Abstract: A novel wireless temperature sensor and non-intrusive temperature measurement method for bearing monitoring were proposed in this paper, based on spectrum parameter analysis of CdTe quantum dots films. The CdTe QDs were synthesized and were used in constructing of a sensor film by means of Layer-by-layer Electrostatic Self-assembly method. The fluorescence spectrum properties of the sensor were characterized. At rotation speed 5000–6000 r/min, bearing cage and inner ring temperature were presented first in this paper by the CdTe QDs sensor. The results were verified by theoretical analysis and by thermocouples, with an error typically below 10% or smaller. Compared to the traditional outer ring monitoring, the measurement and monitoring of bearing rolling elements is of very importance, especially at high rotation speed.

  4. Variations in Ring Particle Cooling across Saturn's Rings with Cassini CIRS

    Science.gov (United States)

    Brooks, S. M.; Spilker, L. J.; Pilorz, S.; Edgington, S. G.; Déau, E.; Altobelli, N.

    2010-12-01

    Cassini's Composite Infrared Spectrometer has recorded over two million of spectra of Saturn's rings in the far infrared since arriving at Saturn in 2004. CIRS records far infrared radiation between 10 and 600 cm-1 ( 16.7 and 1000 μ {m} ) at focal plane 1 (FP1), which has a field of view of 3.9 mrad. Thermal emission from Saturn’s rings peaks in this wavelength range. Ring temperatures can be inferred from FP1 data. By tracking how ring temperatures vary, we can determine the thermal inertia of the rings. Previous studies have shown that the rings' thermal inertia, a measure of their response to changes in the thermal environment, varies from ring to ring. Thermal inertia can provide insight into the physical structure of Saturn's ring particles and their regoliths. Low thermal inertia and rapidly changing temperatures are suggestive of ring particles that have more porous or fluffy regoliths or that are riddled with cracks. Solid particles can be expected to have higher thermal inertias. Ferrari et al. (2005) fit thermal inertia values of 5218 {Jm)-2 {K}-1 {s}-1/2 to their B ring data and 6412 {Jm)-2 {K}-1 {s}-1/2 to their C ring data. In this work we focus on CIRS observations of the shadowed portion of Saturn's rings. The rings’ thermal budget is dominated by its absorption of solar radiation. As a result, ring particles abruptly cool as they traverse Saturn's shadow. From these shadow observations we can create cooling curves at specific locations across the rings. We will show that the rings' cooling curves and thus their thermal inertia vary not only from ring to ring, but by location within the individual rings. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Copyright 2010 California Institute of Technology. Government sponsorship acknowledged.

  5. Low Cost Efficient Deliverying Video Surveillance Service to Moving Guard for Smart Home.

    Science.gov (United States)

    Gualotuña, Tatiana; Macías, Elsa; Suárez, Álvaro; C, Efraín R Fonseca; Rivadeneira, Andrés

    2018-03-01

    Low-cost video surveillance systems are attractive for Smart Home applications (especially in emerging economies). Those systems use the flexibility of the Internet of Things to operate the video camera only when an intrusion is detected. We are the only ones that focus on the design of protocols based on intelligent agents to communicate the video of an intrusion in real time to the guards by wireless or mobile networks. The goal is to communicate, in real time, the video to the guards who can be moving towards the smart home. However, this communication suffers from sporadic disruptions that difficults the control and drastically reduces user satisfaction and operativity of the system. In a novel way, we have designed a generic software architecture based on design patterns that can be adapted to any hardware in a simple way. The implanted hardware is of very low economic cost; the software frameworks are free. In the experimental tests we have shown that it is possible to communicate to the moving guard, intrusion notifications (by e-mail and by instant messaging), and the first video frames in less than 20 s. In addition, we automatically recovered the frames of video lost in the disruptions in a transparent way to the user, we supported vertical handover processes and we could save energy of the smartphone's battery. However, the most important thing was that the high satisfaction of the people who have used the system.

  6. Low Cost Efficient Deliverying Video Surveillance Service to Moving Guard for Smart Home

    Science.gov (United States)

    Gualotuña, Tatiana; Fonseca C., Efraín R.; Rivadeneira, Andrés

    2018-01-01

    Low-cost video surveillance systems are attractive for Smart Home applications (especially in emerging economies). Those systems use the flexibility of the Internet of Things to operate the video camera only when an intrusion is detected. We are the only ones that focus on the design of protocols based on intelligent agents to communicate the video of an intrusion in real time to the guards by wireless or mobile networks. The goal is to communicate, in real time, the video to the guards who can be moving towards the smart home. However, this communication suffers from sporadic disruptions that difficults the control and drastically reduces user satisfaction and operativity of the system. In a novel way, we have designed a generic software architecture based on design patterns that can be adapted to any hardware in a simple way. The implanted hardware is of very low economic cost; the software frameworks are free. In the experimental tests we have shown that it is possible to communicate to the moving guard, intrusion notifications (by e-mail and by instant messaging), and the first video frames in less than 20 s. In addition, we automatically recovered the frames of video lost in the disruptions in a transparent way to the user, we supported vertical handover processes and we could save energy of the smartphone's battery. However, the most important thing was that the high satisfaction of the people who have used the system. PMID:29494551

  7. Low Cost Efficient Deliverying Video Surveillance Service to Moving Guard for Smart Home

    Directory of Open Access Journals (Sweden)

    Tatiana Gualotuña

    2018-03-01

    Full Text Available Low-cost video surveillance systems are attractive for Smart Home applications (especially in emerging economies. Those systems use the flexibility of the Internet of Things to operate the video camera only when an intrusion is detected. We are the only ones that focus on the design of protocols based on intelligent agents to communicate the video of an intrusion in real time to the guards by wireless or mobile networks. The goal is to communicate, in real time, the video to the guards who can be moving towards the smart home. However, this communication suffers from sporadic disruptions that difficults the control and drastically reduces user satisfaction and operativity of the system. In a novel way, we have designed a generic software architecture based on design patterns that can be adapted to any hardware in a simple way. The implanted hardware is of very low economic cost; the software frameworks are free. In the experimental tests we have shown that it is possible to communicate to the moving guard, intrusion notifications (by e-mail and by instant messaging, and the first video frames in less than 20 s. In addition, we automatically recovered the frames of video lost in the disruptions in a transparent way to the user, we supported vertical handover processes and we could save energy of the smartphone's battery. However, the most important thing was that the high satisfaction of the people who have used the system.

  8. Design of a polynomial ring based symmetric homomorphic encryption scheme

    Directory of Open Access Journals (Sweden)

    Smaranika Dasgupta

    2016-09-01

    Full Text Available Security of data, especially in clouds, has become immensely essential for present-day applications. Fully homomorphic encryption (FHE is a great way to secure data which is used and manipulated by untrusted applications or systems. In this paper, we propose a symmetric FHE scheme based on polynomial over ring of integers. This scheme is somewhat homomorphic due to accumulation of noise after few operations, which is made fully homomorphic using a refresh procedure. After certain amount of homomorphic computations, large ciphertexts are refreshed for proper decryption. The hardness of the scheme is based on the difficulty of factorizing large integers. Also, it requires polynomial addition which is computationally cost effective. Experimental results are shown to support our claim.

  9. Plasmonic Refractive Index Sensor with High Figure of Merit Based on Concentric-Rings Resonator

    Science.gov (United States)

    Zhang, Zhaojian; Yang, Junbo; He, Xin; Zhang, Jingjing; Huang, Jie; Chen, Dingbo; Han, Yunxin

    2018-01-01

    A plasmonic refractive index (RI) sensor based on metal-insulator-metal (MIM) waveguide coupled with concentric double rings resonator (CDRR) is proposed and investigated numerically. Utilizing the novel supermodes of the CDRR, the FWHM of the resonant wavelength can be modulated, and a sensitivity of 1060 nm/RIU with high figure of merit (FOM) 203.8 is realized in the near-infrared region. The unordinary modes, as well as the influence of structure parameters on the sensing performance, are also discussed. Such plasmonic sensor with simple framework and high optical resolution could be applied to on-chip sensing systems and integrated optical circuits. Besides, the special cases of bio-sensing and triple rings are also discussed. PMID:29300331

  10. Learning Without Boundaries: A NASA - National Guard Bureau Distance Learning Partnership

    Science.gov (United States)

    Anderson, Susan H.; Chilelli, Christopher J.; Picard, Stephan

    2003-01-01

    With a variety of high-quality live interactive educational programs originating at the Johnson Space Center in Houston, Texas and other space and research centers, the US space agency NASA (National Aeronautics and Space Administration) has a proud track record of connecting with students throughout the world and stimulating their creativity and collaborative skills by teaching them underlying scientific and technological underpinnings of space exploration. However, NASA desires to expand its outreach capability for this type of interactive instruction. In early 2002, NASA and the National Guard Bureau -- using the Guard's nationwide system of state-ofthe-art classrooms and high bandwidth network -- began a collaboration to extend the reach of NASA content and educational programs to more of America's young people. Already, hundreds of elementary, middle, and high school students have visited Guard e-Learning facilities and participated in interactive NASA learning events. Topics have included experimental flight, satellite imagery-interpretation, and Mars exploration. Through this partnership, NASA and the National Guard are enabling local school systems throughout the United States (and, increasingly, the world) to use the excitement of space flight to encourage their students to become passionate about the possibility of one day serving as scientists, mathematicians, technologists, and engineers. At the 54th International Astronautical Conference MAJ Stephan Picard, the guiding visionary behind the Guard's partnership with NASA, and Chris Chilelli, an educator and senior instructional designer at NASA, will share with attendees background on NASA's educational products and the National Guard's distributed learning network; will discuss the unique opportunity this partnership already has provided students and teachers throughout the United States; will offer insights into the formation by government entities of e-Learning partnerships with one another; and will

  11. Dynamics of long ring Raman fiber laser

    Science.gov (United States)

    Sukhanov, Sergey V.; Melnikov, Leonid A.; Mazhirina, Yulia A.

    2016-04-01

    The numerical model for dynamics of long fiber ring Raman laser is proposed. The model is based on the transport equations and Courant-Isaacson-Rees numerical method. Different regimes of a long ring fiber Raman laser are investigated.

  12. Efficient authentication scheme based on near-ring root extraction problem

    Science.gov (United States)

    Muthukumaran, V.; Ezhilmaran, D.

    2017-11-01

    An authentication protocolis the type of computer communication protocol or cryptography protocol specifically designed for transfer of authentication data between two entities. We have planned a two new entity authentication scheme on the basis of root extraction problem near-ring in this article. We suggest that this problem is suitably difficult to serve as a cryptographic assumption over the platform of near-ring N. The security issues also discussed.

  13. Alternative loop rings

    CERN Document Server

    Goodaire, EG; Polcino Milies, C

    1996-01-01

    For the past ten years, alternative loop rings have intrigued mathematicians from a wide cross-section of modern algebra. As a consequence, the theory of alternative loop rings has grown tremendously. One of the main developments is the complete characterization of loops which have an alternative but not associative, loop ring. Furthermore, there is a very close relationship between the algebraic structures of loop rings and of group rings over 2-groups. Another major topic of research is the study of the unit loop of the integral loop ring. Here the interaction between loop rings and group ri

  14. 5 CFR 831.306 - Service as a National Guard technician before January 1, 1969.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Service as a National Guard technician... National Guard technician before January 1, 1969. (a) Definitions. In this section—(1) Service as a National Guard technician is service performed under section 709 of title 32, United States Code (or under...

  15. Primitivity and weak distributivity in near rings and matrix near rings

    International Nuclear Information System (INIS)

    Abbasi, S.J.

    1993-08-01

    This paper shows the structure of matrix near ring constructed over a weakly distributive and primative near ring. It is proved that a weakly distributive primitive near ring is a ring and the matrix near rings constructed over it is also a bag. (author). 14 refs

  16. MAPK cascades in guard cell signal transduction

    Directory of Open Access Journals (Sweden)

    Yuree eLee

    2016-02-01

    Full Text Available Guard cells form stomata on the epidermis and continuously respond to endogenous and environmental stimuli to fine-tune the gas exchange and transpirational water loss, processes which involve mitogen-activated protein kinase (MAPK cascades. MAPKs form three-tiered kinase cascades with MAPK kinases and MAPK kinase kinases, by which signals are transduced to the target proteins. MAPK cascade genes are highly conserved in all eukaryotes, and they play crucial roles in myriad developmental and physiological processes. MAPK cascades function during biotic and abiotic stress responses by linking extracellular signals received by receptors to cytosolic events and gene expression. In this review, we highlight recent findings and insights into MAPK-mediated guard cell signaling, including the specificity of MAPK cascades and the remaining questions.

  17. Deconvolution of the tree ring based delta13C record

    International Nuclear Information System (INIS)

    Peng, T.; Broecker, W.S.; Freyer, H.D.; Trumbore, S.

    1983-01-01

    We assumed that the tree-ring based 13 C/ 12 C record constructed by Freyer and Belacy (1983) to be representative of the fossil fuel and forest-soil induced 13 C/ 12 C change for atmospheric CO 2 . Through the use of a modification of the Oeschger et al. ocean model, we have computed the contribution of the combustion of coal, oil, and natural gas to this observed 13 C/ 12 C change. A large residual remains when the tree-ring-based record is corrected for the contribution of fossil fuel CO 2 . A deconvolution was performed on this residual to determine the time history and magnitude of the forest-soil reservoir changes over the past 150 years. Several important conclusions were reached. (1) The magnitude of the integrated CO 2 input from these sources was about 1.6 times that from fossil fuels. (2) The forest-soil contribution reached a broad maximum centered at about 1900. (3) Over the 2 decade period covered by the Mauna Loa atmospheric CO 2 content record, the input from forests and soils was about 30% that from fossil fuels. (4) The 13 C/ 12 C trend over the last 20 years was dominated by the input of fossil fuel CO 2 . (5) The forest-soil release did not contribute significantly to the secular increase in atmospheric CO 2 observed over the last 20 years. (6) The pre-1850 atmospheric p2 values must have been in the range 245 to 270 x 10 -6 atmospheres

  18. Noise Source Identification of a Ring-Plate Cycloid Reducer Based on Coherence Analysis

    OpenAIRE

    Yang, Bing; Liu, Yan

    2013-01-01

    A ring-plate-type cycloid speed reducer is one of the most important reducers owing to its low volume, compactness, smooth and high performance, and high reliability. The vibration and noise tests of the reducer prototype are completed using the HEAD acoustics multichannel noise test and analysis system. The characteristics of the vibration and noise are obtained based on coherence analysis and the noise sources are identified. The conclusions provide the bases for further noise research and ...

  19. Detecting mode hopping in single-longitudinal-mode fiber ring lasers based on an unbalanced fiber Michelson interferometer.

    Science.gov (United States)

    Ma, Mingxiang; Hu, Zhengliang; Xu, Pan; Wang, Wei; Hu, Yongming

    2012-10-20

    A method of detecting mode hopping for single-longitudinal-mode (SLM) fiber ring lasers has been proposed and experimentally demonstrated. The method that is based on an unbalanced Michelson interferometer (MI) utilizing phase generated carrier modulation instantly transforms mode-hopping dynamics into steep phase changes of the interferometer. Multiform mode hops in an SLM erbium-doped fiber ring laser with an 18.6 MHz mode spacing have been detected exactly in real-time domain and discussed in detail. Numerical results show that the MI-based method has a high testing sensitivity for identifying mode hopping, which will play a significant role in evaluating the output stability of SLM fiber lasers.

  20. Note on Ideal Based Zero-Divisor Graph of a Commutative Ring

    Directory of Open Access Journals (Sweden)

    Mallika A.

    2017-12-01

    Full Text Available In this paper, we consider the ideal based zero divisor graph ΓI(R of a commutative ring R. We discuss some graph theoretical properties of ΓI(R in relation with zero divisor graph. We also relate certain parameters like vertex chromatic number, maximum degree and minimum degree for the graph ΓI(R with that of Γ(R/I . Further we determine a necessary and sufficient condition for the graph to be Eulerian and regular.

  1. Ring on the hook: placing a ring on a moving and pendulating hook based on visual input

    DEFF Research Database (Denmark)

    Kjær-Nielsen, Anders; Buch, Anders Glent; Jensen, Andreas Kryger

    2011-01-01

    Purpose – The purpose of this paper is to describe a robot vision system which put rings on hooks that are moving freely on a conveyor belt. The hook can show a significant swinging which can be well approximated by a pendulum movement. The problem is of large relevance for many industrial...... applications and the challenge is to compute a 3D pose that is sufficiently precise to allow for successful placements of the rings. Design/methodology/approach – This requires a fast and precise tracking and a compensation for latencies connected to the processing of visual information as well as the actual...

  2. The Hi-Ring architecture for datacentre networks

    DEFF Research Database (Denmark)

    Galili, Michael; Kamchevska, Valerija; Ding, Yunhong

    2016-01-01

    This paper summarizes recent work on a hierarchical ring-based network architecture (Hi-Ring) for datacentre and short-range applications. The architecture allows leveraging benefits of optical switching technologies while maintaining a high level of connection granularity. We discuss results...

  3. Ring recognition in the CBM RICH detector

    International Nuclear Information System (INIS)

    Lebedev, S.; Ososkov, G.; Hoehne, C.

    2007-01-01

    Two algorithms of ring recognition, a standalone ring finder (using only RICH information) and an algorithm based on the information from vertex tracks are described. The fake ring problem and its solution using a set of two-dimensional cuts or an artificial neural network are discussed. Results of a comparative study are given. All developed algorithms were tested on large statistics of simulated events and were then included into the CBM framework for common use

  4. Interaction of ring dark solitons with ring impurities in Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Xue Jukui

    2005-01-01

    The interaction of ring dark solitons/vortexes with the ring-shaped repulsive and attractive impurities in two-dimensional Bose-Einstein condensates is investigated numerically. Very rich interaction phenomena are obtained, i.e., not only the interaction between the ring soliton and the impurity, but also the interaction between vortexes and the impurity. The interaction characters, i.e., snaking of ring soliton, quasitrapping or reflection of ring soliton and vortexes by the impurity, strongly depend on initial ring soliton velocity, impurity strength, initial position of ring soliton and impurity. The numerical results also reveal that ring dark solitons/vortexes can be trapped and dragged by an adiabatically moving attractive ring impurity

  5. Joint FAM/Line Management Assessment Report on LLNL Machine Guarding Safety Program

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, J. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-07-19

    The LLNL Safety Program for Machine Guarding is implemented to comply with requirements in the ES&H Manual Document 11.2, "Hazards-General and Miscellaneous," Section 13 Machine Guarding (Rev 18, issued Dec. 15, 2015). The primary goal of this LLNL Safety Program is to ensure that LLNL operations involving machine guarding are managed so that workers, equipment and government property are adequately protected. This means that all such operations are planned and approved using the Integrated Safety Management System to provide the most cost effective and safest means available to support the LLNL mission.

  6. Storage Rings

    International Nuclear Information System (INIS)

    Fischer, W.

    2010-01-01

    Storage rings are circular machines that store particle beams at a constant energy. Beams are stored in rings without acceleration for a number of reasons (Tab. 1). Storage rings are used in high-energy, nuclear, atomic, and molecular physics, as well as for experiments in chemistry, material and life sciences. Parameters for storage rings such as particle species, energy, beam intensity, beam size, and store time vary widely depending on the application. The beam must be injected into a storage ring but may not be extracted (Fig. 1). Accelerator rings such as synchrotrons are used as storage rings before and after acceleration. Particles stored in rings include electrons and positrons; muons; protons and anti-protons; neutrons; light and heavy, positive and negative, atomic ions of various charge states; molecular and cluster ions, and neutral polar molecules. Spin polarized beams of electrons, positrons, and protons were stored. The kinetic energy of the stored particles ranges from 10 -6 eV to 3.5 x 10 12 eV (LHC, 7 x 10 12 eV planned), the number of stored particles from one (ESR) to 1015 (ISR). To store beam in rings requires bending (dipoles) and transverse focusing (quadrupoles). Higher order multipoles are used to correct chromatic aberrations, to suppress instabilities, and to compensate for nonlinear field errors of dipoles and quadrupoles. Magnetic multipole functions can be combined in magnets. Beams are stored bunched with radio frequency systems, and unbunched. The magnetic lattice and radio frequency system are designed to ensure the stability of transverse and longitudinal motion. New technologies allow for better storage rings. With strong focusing the beam pipe dimensions became much smaller than previously possible. For a given circumference superconducting magnets make higher energies possible, and superconducting radio frequency systems allow for efficient replenishment of synchrotron radiation losses of large current electron or positron beams

  7. Common and unique elements of the ABA-regulated transcriptome of Arabidopsis guard cells

    Directory of Open Access Journals (Sweden)

    Zhao Zhixin

    2011-05-01

    Full Text Available Abstract Background In the presence of drought and other desiccating stresses, plants synthesize and redistribute the phytohormone abscisic acid (ABA. ABA promotes plant water conservation by acting on specialized cells in the leaf epidermis, guard cells, which border and regulate the apertures of stomatal pores through which transpirational water loss occurs. Following ABA exposure, solute uptake into guard cells is rapidly inhibited and solute loss is promoted, resulting in inhibition of stomatal opening and promotion of stomatal closure, with consequent plant water conservation. There is a wealth of information on the guard cell signaling mechanisms underlying these rapid ABA responses. To investigate ABA regulation of gene expression in guard cells in a systematic genome-wide manner, we analyzed data from global transcriptomes of guard cells generated with Affymetrix ATH1 microarrays, and compared these results to ABA regulation of gene expression in leaves and other tissues. Results The 1173 ABA-regulated genes of guard cells identified by our study share significant overlap with ABA-regulated genes of other tissues, and are associated with well-defined ABA-related promoter motifs such as ABREs and DREs. However, we also computationally identified a unique cis-acting motif, GTCGG, associated with ABA-induction of gene expression specifically in guard cells. In addition, approximately 300 genes showing ABA-regulation unique to this cell type were newly uncovered by our study. Within the ABA-regulated gene set of guard cells, we found that many of the genes known to encode ion transporters associated with stomatal opening are down-regulated by ABA, providing one mechanism for long-term maintenance of stomatal closure during drought. We also found examples of both negative and positive feedback in the transcriptional regulation by ABA of known ABA-signaling genes, particularly with regard to the PYR/PYL/RCAR class of soluble ABA receptors and

  8. Common and unique elements of the ABA-regulated transcriptome of Arabidopsis guard cells

    Science.gov (United States)

    2011-01-01

    Background In the presence of drought and other desiccating stresses, plants synthesize and redistribute the phytohormone abscisic acid (ABA). ABA promotes plant water conservation by acting on specialized cells in the leaf epidermis, guard cells, which border and regulate the apertures of stomatal pores through which transpirational water loss occurs. Following ABA exposure, solute uptake into guard cells is rapidly inhibited and solute loss is promoted, resulting in inhibition of stomatal opening and promotion of stomatal closure, with consequent plant water conservation. There is a wealth of information on the guard cell signaling mechanisms underlying these rapid ABA responses. To investigate ABA regulation of gene expression in guard cells in a systematic genome-wide manner, we analyzed data from global transcriptomes of guard cells generated with Affymetrix ATH1 microarrays, and compared these results to ABA regulation of gene expression in leaves and other tissues. Results The 1173 ABA-regulated genes of guard cells identified by our study share significant overlap with ABA-regulated genes of other tissues, and are associated with well-defined ABA-related promoter motifs such as ABREs and DREs. However, we also computationally identified a unique cis-acting motif, GTCGG, associated with ABA-induction of gene expression specifically in guard cells. In addition, approximately 300 genes showing ABA-regulation unique to this cell type were newly uncovered by our study. Within the ABA-regulated gene set of guard cells, we found that many of the genes known to encode ion transporters associated with stomatal opening are down-regulated by ABA, providing one mechanism for long-term maintenance of stomatal closure during drought. We also found examples of both negative and positive feedback in the transcriptional regulation by ABA of known ABA-signaling genes, particularly with regard to the PYR/PYL/RCAR class of soluble ABA receptors and their downstream targets

  9. Early Intervention to Reduce Alcohol Misuse and Abuse in the Ohio Army National Guard

    Science.gov (United States)

    2017-09-01

    PTSD, depression , 7 suicidality , lowered resilience and work performance.  Studies consistently find that substantial number of Guard members misuse...including PTSD, depression , suicidality , lowered resilience and work performance.  Studies consistently find that substantial number of Guard members misuse...Guard members that contributes to and complicates other problems including PTSD, depression , suicidality , lowered resilience and work performance

  10. 29 CFR 1910.23 - Guarding floor and wall openings and holes.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Guarding floor and wall openings and holes. 1910.23 Section... floor and wall openings and holes. (a) Protection for floor openings. (1) Every stairway floor opening... opening and hole shall be guarded by a standard skylight screen or a fixed standard railing on all exposed...

  11. Rings in drugs.

    Science.gov (United States)

    Taylor, Richard D; MacCoss, Malcolm; Lawson, Alastair D G

    2014-07-24

    We have analyzed the rings, ring systems, and frameworks in drugs listed in the FDA Orange Book to understand the frequency, timelines, molecular property space, and the application of these rings in different therapeutic areas and target classes. This analysis shows that there are only 351 ring systems and 1197 frameworks in drugs that came onto the market before 2013. Furthermore, on average six new ring systems enter drug space each year and approximately 28% of new drugs contain a new ring system. Moreover, it is very unusual for a drug to contain more than one new ring system and the majority of the most frequently used ring systems (83%) were first used in drugs developed prior to 1983. These observations give insight into the chemical novelty of drugs and potentially efficient ways to assess compound libraries and develop compounds from hit identification to lead optimization and beyond.

  12. Quantum mechanical design of efficient second-order nonlinear optical materials based on heteroaromatic imido-substituted hexamolybdates: first theoretical framework of POM-based heterocyclic aromatic rings.

    Science.gov (United States)

    Janjua, Muhammad Ramzan Saeed Ashraf

    2012-11-05

    This work was inspired by a previous report (Janjua et al. J. Phys. Chem. A 2009, 113, 3576-3587) in which the nonlinear-optical (NLO) response strikingly improved with an increase in the conjugation path of the ligand and the nature of hexamolybdates (polyoxometalates, POMs) was changed into a donor by altering the direction of charge transfer with a second aromatic ring. Herein, the first theoretical framework of POM-based heteroaromatic rings is found to be another class of excellent NLO materials having double heteroaromatic rings. First hyperpolarizabilities of a large number of push-pull-substituted conjugated systems with heteroaromatic rings have been calculated. The β components were computed at the density functional theory (DFT) level (BP86 geometry optimizations and LB94 time-dependent DFT). The largest β values are obtained with a donor (hexamolybdates) on the benzene ring and an acceptor (-NO(2)) on pyrrole, thiophene, and furan rings. The pyrrole imido-substituted hexamolybdate (system 1c) has a considerably large first hyperpolarizability, 339.00 × 10(-30) esu, and it is larger than that of (arylimido)hexamolybdate, calculated as 0.302 × 10(-30) esu (reference system 1), because of the double aromatic rings in the heteroaromatic imido-substituted hexamolybdates. The heteroaromatic rings act as a conjugation bridge between the electron acceptor (-NO(2)) and donor (polyanion). The introduction of an electron donor into heteroaromatic rings significantly enhances the first hyperpolarizabilities because the electron-donating ability is substantially enhanced when the electron donor is attached to the heterocyclic aromatic rings. Interposing five-membered auxiliary fragments between strong donor (polyanion) or acceptor (-NO(2)) groups results in a large computed second-order NLO response. The present investigation provides important insight into the NLO properties of (heteroaromatic) imido-substituted hexamolybdate derivatives because these compounds

  13. ARMY NATIONAL GUARD: Enhanced Brigade Readiness Improved but Personnel and Workload Are Problems

    National Research Council Canada - National Science Library

    2000-01-01

    .... Reserve units such as the National Guard's 15 Enhanced Separate Brigades, the Guard's highest priority combat units, provide fighting forces at about 2530 percent of the cost of active units due...

  14. On Learning Ring-Sum-Expansions

    DEFF Research Database (Denmark)

    Fischer, Paul; Simon, H. -U.

    1992-01-01

    The problem of learning ring-sum-expansions from examples is studied. Ring-sum-expansions (RSE) are representations of Boolean functions over the base {#123;small infinum, (+), 1}#125;, which reflect arithmetic operations in GF(2). k-RSE is the class of ring-sum-expansions containing only monomials...... of length at most k:. term-RSE is the class of ring-sum-expansions having at most I: monomials. It is shown that k-RSE, k>or=1, is learnable while k-term-RSE, k>2, is not learnable if RPnot=NP. Without using a complexity-theoretical hypothesis, it is proven that k-RSE, k>or=1, and k-term-RSE, k>or=2 cannot...... be learned from positive (negative) examples alone. However, if the restriction that the hypothesis which is output by the learning algorithm is also a k-RSE is suspended, then k-RSE is learnable from positive (negative) examples only. Moreover, it is proved that 2-term-RSE is learnable by a conjunction...

  15. Computerspil og læring

    Directory of Open Access Journals (Sweden)

    Lasse Juel Larsen

    2015-02-01

    Full Text Available Game-based learning og gamification er ord, der ofte optræder i forbindelse med computerspil og læring. Denne artikel vil analytisk undersøge, hvordan computerspil og læring går i forbindelse med hinanden. Artikel tager afsæt i Gregory Batesons læringsteori og læser denne igennem det kommercielle computerspil StarCraft 2 fra Blizzard Intertainment. Batesons læringsteori vil ikke alene blive gennemgået, men også udvidet og perspektiveret.  Formålet med denne indsats er at skabe et afsæt, der kan demonstrere, hvordan læring foregår i computerspil. Herefter vil afsættet blive anvendt til at destillere et læringsteoretisk udkast. Artiklen falder således i to dele, hvor den første analytisk adresserer, hvordan læring i computerspil foregår, mens den anden er teoriproducerende på baggrund af resultaterne fra første del.

  16. Evaporation-induced self-assembly of quantum dots-based concentric rings on polymer-based nanocomposite films.

    Science.gov (United States)

    Zhang, Shaofu; Luan, Weiling; Zhong, Qixin; Yin, Shaofeng; Yang, Fuqian

    2016-10-12

    The "ball-on-film" template is used to construct concentric rings on the surface of PMMA-QDs (polymethyl methacrylate - quantum dots) nanocomposite films via the evaporation of pure chloroform droplets, which are confined by a steel ball. The concentric rings consist of QDs, as revealed by the fluorescence images of the concentric rings. The photoluminescence intensity of the concentric rings increases with the increase of the distance to the ball center, suggesting that the amount of QDs accumulated around the contact line at individual stick state increases with the increase of the distance to the ball center. Both the wavelength and cross-sectional area (width) of the concentric rings increase approximately linearly with increasing distance to the ball center, independent of the ball size, the film thickness and the QDs concentration. For the PMMA-QDs nanocomposite films prepared from the same QDs concentration in chloroform, the thicker the PMMA-QDs nanocomposite film, the larger the wavelength for the same distance to the ball center. The effect of confinement of two steel balls on the surface patterns over the PMMA-QDs nanocomposite films is studied via a template of "two spheres on film". Symmetric surface patterns are formed. There exist two types of featureless zone between the two balls, depending on the distance between the two balls: one is the inner featureless zone and the other is the outer featureless zone. The size of both featureless zones increases with the increase of the ball distance.

  17. Microarray Expression Analyses of Arabidopsis Guard Cells and Isolation of a Recessive Abscisic Acid Hypersensitive Protein Phosphatase 2C MutantW⃞

    Science.gov (United States)

    Leonhardt, Nathalie; Kwak, June M.; Robert, Nadia; Waner, David; Leonhardt, Guillaume; Schroeder, Julian I.

    2004-01-01

    Oligomer-based DNA Affymetrix GeneChips representing about one-third of Arabidopsis (Arabidopsis thaliana) genes were used to profile global gene expression in a single cell type, guard cells, identifying 1309 guard cell–expressed genes. Highly pure preparations of guard cells and mesophyll cells were isolated in the presence of transcription inhibitors that prevented induction of stress-inducible genes during cell isolation procedures. Guard cell expression profiles were compared with those of mesophyll cells, resulting in identification of 64 transcripts expressed preferentially in guard cells. Many large gene families and gene duplications are known to exist in the Arabidopsis genome, giving rise to redundancies that greatly hamper conventional genetic and functional genomic analyses. The presented genomic scale analysis identifies redundant expression of specific isoforms belonging to large gene families at the single cell level, which provides a powerful tool for functional genomic characterization of the many signaling pathways that function in guard cells. Reverse transcription–PCR of 29 genes confirmed the reliability of GeneChip results. Statistical analyses of promoter regions of abscisic acid (ABA)–regulated genes reveal an overrepresented ABA responsive motif, which is the known ABA response element. Interestingly, expression profiling reveals ABA modulation of many known guard cell ABA signaling components at the transcript level. We further identified a highly ABA-induced protein phosphatase 2C transcript, AtP2C-HA, in guard cells. A T-DNA disruption mutation in AtP2C-HA confers ABA-hypersensitive regulation of stomatal closing and seed germination. The presented data provide a basis for cell type–specific genomic scale analyses of gene function. PMID:14973164

  18. Relating Operational Art to the National Guard State Partnership Program

    Science.gov (United States)

    2014-05-15

    Program Coordinator GEF Global Employment of the Force DSCA Defense Support of Civil Authorities BCA Budget Control Act NATO North Atlantic Treaty...between Florida and the U.S. Virgin Islands are referred to as the Regional Security System (RSS). Florida and the U.S. Virgin Islands partner with... Atlantic Treaty Organization (NATO) in 2004 due, in part, to the mentorship from the Maryland National Guard.54 Not only did the Maryland National Guard

  19. Preliminary assessment report for National Guard Training Center, Georgia Army National Guard, Fort Stewart, Georgia

    International Nuclear Information System (INIS)

    1993-07-01

    This report presents the results of the preliminary assessment (PA) conducted by Argonne National Laboratory at the Georgia Army National Guard (GAARNG) facility near Hinesville, Georgia, known as the National Guard Training Center (NGTC). Preliminary assessments of federal facilities are being conducted to compile the information necessary for completing preremedial activities and to provide a priority basis for completing corrective actions (where necessary) in response to releases of hazardous substances. The principal objective of the PA is to characterize the site accurately and determine the need for further action by examining previous site activities, types and quantities of hazardous substances utilized, and potential pathways by which contamination could affect public health and the environment. The scope of this assessment is limited to the facilities and past activities contained within the NGTC. Preliminary assessment site score sheet information is also provided for the NGTC. However, this assessment report is intended to be read in conjunction with a previous IRP assessment of Fort Stewart completed in 1992 (USATHAMA 1992) and to provide comprehensive information on the NGTC area for incorporation with information contained in that previous assessment for the entirety of Fort Stewart

  20. INJECTION EFFICIENCY IN COMPTON RING NESTOR

    Directory of Open Access Journals (Sweden)

    P. I. Gladkikh

    2017-12-01

    Full Text Available NESTOR is the hard X-ray source that is under commissioning at NSC KIPT. NESTOR based on the Compton scattering of laser photons on relativistic electrons. The structure of the facility can be represented as the following components: a linear accelerator, a transport channel, a storage ring, and a laser-optical system. Electrons are stored in the storage ring for energy of 40-200 MeV. Inevitable alignment errors of magnetic elements are strongly effect on the beam dynamics in the storage ring. These errors lead to a shift of the equilibrium orbit relative to the ideal one. Significant shift of the equilibrium orbit could lead to loss of the beam on physical apertures. Transverse sizes of electron and laser beams are only few tens of microns at the interaction point. The shift of electron beam at the interaction point could greatly complicate the operation adjustment of storage ring without sufficient beam position diagnostic system. This article presents the simulation results of the efficiency of electron beam accumulation in the NESTOR storage ring. Also, this article is devoted to electron beam dynamics due to alignment errors of magnetic element in the ring.

  1. Ring-shaped functions and Wigner 6j-symbols

    International Nuclear Information System (INIS)

    Mardoyan, L.G.; Erevanskij Gosudarstvennyj Univ., Erevan

    2006-01-01

    The explicit expression for the ring-shaped matrix connecting the ring-shaped functions relating to different values of the axial parameter is obtained. The connection of this matrix with Wigner 6j-symbols is found out. The motion of quantum particle in the ring-shaped model with the zero priming potential is investigated. The bases of this model, which are factored in spherical cylindrical coordinates, are obtained. The formula generalizing the Rayleigh expansion of a plane wave with respect to spherical waves in the ring-shaped model is deduced [ru

  2. 48 CFR 3009.171-3 - Determination of eligibility for award of FPS guard service contracts.

    Science.gov (United States)

    2010-10-01

    ... eligibility for award of FPS guard service contracts. 3009.171-3 Section 3009.171-3 Federal Acquisition... eligibility for award of FPS guard service contracts. (a) Contracting officers shall make a determination of eligibility for award of FPS guard service contracts upon identification of the apparent successful offeror as...

  3. Research methods to develop Measures of Effectiveness of the United States Coast Guard`s Vessel Inspection and Boarding Program. Volume 2, Main report

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, T.; Cox, R. [Sandia National Labs., Albuquerque, NM (United States); Gawande, K. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Economics; Stone, R.; Waisel, L.; Wallace, W.A. [Rensselaer Polytechnic Inst., Troy, New York (United States). Dept. of Decision Sciences and Engineering Systems

    1995-04-01

    The primary objective of this study is to provide Measures of Effectiveness (MOEs) of the US Coast Guard Marine Inspection and Boarding Program based on objective scientific methods. A secondary objective of the study is to provide USCG management with a methodologically and theoretically sound aid to effective policy decision-making. The MOEs constructed in this study are specific to the Marine Inspection and Boarding Program, but the methodology of the study is based on sound theoretical principles that are probably applicable to a range of USCG activities. Hence the methodology applied equally to other important USCG programs and can be similarly used to measure their effectiveness and as an aid to decision-making.

  4. NuFact muon storage ring: study of a triangle design based on solenoid focusing decay straights

    Energy Technology Data Exchange (ETDEWEB)

    Meot, F. [Service Accelerateurs, Laboratoire de Physique Subatomique et de Cosmologie, Universite Joseph Fourier / CNRS-IN2P3, 53 Avenue des Martyrs, F-38026 Grenoble (France)]|[Commissariat a l' Energie Atomique, CEA, 31-33, rue de la Federation (Paris 15e), BP 510, 75752 Paris Cedex 15 (France); Reesy, G. [Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot OX11 0QX (United Kingdom)

    2006-06-15

    Properties of acceptance and beam transmission in a triangle design of the neutrino factory muon decay ring, with decay straights based on solenoidal focusing, are reported.The muon storage ring in the neutrino factory, NuFact, is located at the high energy end of the muon acceleration chain. It delivers the {mu}{sup +}/{mu}{sup -} decay neutrinos to physics detectors. The design of concern here, is a triangle geometry 20 GeV storage ring, upgradable to 50 GeV, (the parameters are given), which features two decay straight sections, each one aiming at a distant detector. The third straight section of the ring is devoted to tuning, collimation and RF. A particularity of the proposed design, is in its being based on solenoid focusing decay straights, which has the virtue of minimizing the betatron amplitudes, compared to equivalent quadrupole focusing. The solenoidal focusing ensures the requested ratio, for the r.m.s. divergences of the 20 GeV muon and the neutrino beam, of 0.1 for an assumed muon normalized r.m.s. emittance of 4800 {pi} mm mr (3 {pi} cm, total). The goal of the present work is to show the viability of this design, in particular as concerns the impact of the solenoid focusing on machine behavior. It addresses the questions of residual coupling, machine acceptance, and concludes with a computation of beam transmission over 1000 turns. The paper has the following structure: 1. Introduction; 2. Working hypothesis; 3. Building-up ray-tracing data; 3.1. Arcs; 3.2. Solenoid straight; 3.3. Tuning/Collimation/RF straight; 3.4. Full ring; 3.4.1. Beam envelopes; 3.4.2. Closed orbits; 3.4.3. Momentum dispersion; 3.5 Large amplitude tracking, preliminary tests; 4. Tracking, linear machine; 4.1. Large amplitude tracking; 4.1.1. 2-D horizontal initial conditions; 4.1.2. 2-D vertical initial conditions; 4.1.3. 4-D + {delta}p/p initial conditions; 4.2. Transmission, 4-D + {delta}p/p, no sextupoles; 4.2.1. {epsilon}{sub x} {epsilon}{sub z} = 3 {pi} cm (norm.), {delta

  5. NuFact muon storage ring: study of a triangle design based on solenoid focusing decay straights

    International Nuclear Information System (INIS)

    Meot, F.; Reesy, G.

    2006-06-01

    Properties of acceptance and beam transmission in a triangle design of the neutrino factory muon decay ring, with decay straights based on solenoidal focusing, are reported.The muon storage ring in the neutrino factory, NuFact, is located at the high energy end of the muon acceleration chain. It delivers the μ + /μ - decay neutrinos to physics detectors. The design of concern here, is a triangle geometry 20 GeV storage ring, upgradable to 50 GeV, (the parameters are given), which features two decay straight sections, each one aiming at a distant detector. The third straight section of the ring is devoted to tuning, collimation and RF. A particularity of the proposed design, is in its being based on solenoid focusing decay straights, which has the virtue of minimizing the betatron amplitudes, compared to equivalent quadrupole focusing. The solenoidal focusing ensures the requested ratio, for the r.m.s. divergences of the 20 GeV muon and the neutrino beam, of 0.1 for an assumed muon normalized r.m.s. emittance of 4800 π mm mr (3 π cm, total). The goal of the present work is to show the viability of this design, in particular as concerns the impact of the solenoid focusing on machine behavior. It addresses the questions of residual coupling, machine acceptance, and concludes with a computation of beam transmission over 1000 turns. The paper has the following structure: 1. Introduction; 2. Working hypothesis; 3. Building-up ray-tracing data; 3.1. Arcs; 3.2. Solenoid straight; 3.3. Tuning/Collimation/RF straight; 3.4. Full ring; 3.4.1. Beam envelopes; 3.4.2. Closed orbits; 3.4.3. Momentum dispersion; 3.5 Large amplitude tracking, preliminary tests; 4. Tracking, linear machine; 4.1. Large amplitude tracking; 4.1.1. 2-D horizontal initial conditions; 4.1.2. 2-D vertical initial conditions; 4.1.3. 4-D + δp/p initial conditions; 4.2. Transmission, 4-D + δp/p, no sextupoles; 4.2.1. ε x ε z = 3 π cm (norm.), δp/p = ±1%; 4.2.2. ε x ε z = 6 π cm (norm.), δp/p ±4

  6. 76 FR 7131 - Safety Zones; Eleventh Coast Guard District Annual Fireworks Events

    Science.gov (United States)

    2011-02-09

    ...-AA00 Safety Zones; Eleventh Coast Guard District Annual Fireworks Events AGENCY: Coast Guard, DHS... permanent safety zones to ensure public safety during annual firework displays at various locations in the... events, delete events that are no longer occurring, add new unlisted annual fireworks events to the...

  7. The mysterious mid-latitude ionosphere of Saturn via ground-based observations of H3+: ring rain and other drivers

    Science.gov (United States)

    O'Donoghue, J.; Moore, L.; Stallard, T.; Melin, H.; Connerney, J. E. P.; Oliversen, R. J.

    2017-09-01

    In 2013, we discovered that the "ring rain" which falls on Saturn from the rings also leaves an imprint on the low-latitude upper-atmosphere. Specifically, the ionospheric-bound H3+ ion appeared to emit brightest where water products are known to fall. Here we show the first re-detections of the imprint of "ring rain" on Saturn's ionosphere, using ground-based Keck telescope data from 2013 and 2014. We have also found that the emission from low-latitudes decreases dramatically from 2011 to 2013, implying a planetary cooling over the time period, but we are unaware of the mechanism of this cooling at present.

  8. Novel Fiber-Optic Ring Acoustic Emission Sensor.

    Science.gov (United States)

    Wei, Peng; Han, Xiaole; Xia, Dong; Liu, Taolin; Lang, Hao

    2018-01-13

    Acoustic emission technology has been applied to many fields for many years. However, the conventional piezoelectric acoustic emission sensors cannot be used in extreme environments, such as those with heavy electromagnetic interference, high pressure, or strong corrosion. In this paper, a novel fiber-optic ring acoustic emission sensor is proposed. The sensor exhibits high sensitivity, anti-electromagnetic interference, and corrosion resistance. First, the principle of a novel fiber-optic ring sensor is introduced. Different from piezoelectric and other fiber acoustic emission sensors, this novel sensor includes both a sensing skeleton and a sensing fiber. Second, a heterodyne interferometric demodulating method is presented. In addition, a fiber-optic ring sensor acoustic emission system is built based on this method. Finally, fiber-optic ring acoustic emission experiments are performed. The novel fiber-optic ring sensor is glued onto the surface of an aluminum plate. The 150 kHz standard continuous sinusoidal signals and broken lead signals are successfully detected by the novel fiber-optic ring acoustic emission sensor. In addition, comparison to the piezoelectric acoustic emission sensor is performed, which shows the availability and reliability of the novel fiber-optic ring acoustic emission sensor. In the future, this novel fiber-optic ring acoustic emission sensor will provide a new route to acoustic emission detection in harsh environments.

  9. Small electrostatic storage rings; also for highly charged ions?

    International Nuclear Information System (INIS)

    Moeller, S.P.; Pedersen, U.V.

    2001-01-01

    Two years ago, a small electrostatic storage ring ELISA (electrostatic ion storage ring, Aarhus) was put into operation. The design of this small 7 m circumference ring was based on electrostatic deflection plates and quadrupoles. This is in contrast to the larger ion storage rings, which are based on magnetic focusing and deflection. The result is a small, relatively inexpensive, storage ring being able to store ions of any mass and any charge at low energy ( -11 mbar resulting in storage times of several tens of seconds for singly charged ions. The maximum number of singly charged ions that can be stored is a few 10 7 . Several experiments have already been performed in ELISA. These include lifetime studies of metastable ions and studies of fullerenes and metal-cluster ions. Lasers are also used for excitation of the circulating ions. Heating/cooling of the ring is possible. Cooling of the ring leads to significantly lower pressures, and correspondingly longer lifetimes. A change of the temperature of the vacuum chambers surrounding the ion beam also leads to a change of the spectrum of the black-body radiation, which has a significant influence on weakly bound negative ions. At the time of writing, at least two other electrostatic storage rings are being built, and more are planned. In the following, the electrostatic storage ring ELISA will be described, and results from some of the initial experiments demonstrating the performance will be shown. The relative merits of such a ring, as opposed to the larger magnetic rings and the smaller ion traps will be discussed. The potential for highly charged ions will be briefly mentioned. (orig.)

  10. 75 FR 53195 - Security Zone; U.S. Coast Guard BSU Seattle, Pier 36, Seattle, WA

    Science.gov (United States)

    2010-08-31

    ... its effects on them and participate in the rulemaking process. Small businesses may send comments on... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 [Docket No. USCG-2010-0021] RIN 1625-AA87 Security Zone; U.S. Coast Guard BSU Seattle, Pier 36, Seattle, WA AGENCY: Coast Guard, DHS. ACTION...

  11. White Ring; White ring

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, H.; Yuzawa, H. [Nikken Sekkei Ltd., Osaka (Japan)

    1998-01-05

    White Ring is a citizen`s gymnasium used for figure skating and short track speed skating games of 18th Winter Olympic Games in 1998. White Ring is composed of a main-arena and a sub-arena. For the main-arena with an area 41mtimes66m, an ice link can be made by disengaging the potable floor and by flowing brine in the bridged polystyrene pipes embedded in the concrete floor. Due to the fortunate groundwater in this site, well water is used for the outside air treatment energy in 63% during heating and in 35% during cooling. Ammonia is used as a cooling medium for refrigerating facility. For the heating of audience area in the large space, heat load from the outside is reduced by enhancing the heat insulation performance of the roof of arena. The audience seats are locally heated using heaters. For the White Ring, high quality environment is realized for games through various functions of the large-scale roof of the large space. Success of the big event was expected. 15 figs., 4 tabs.

  12. 33 CFR 165.506 - Safety Zones; Fifth Coast Guard District Fireworks Displays.

    Science.gov (United States)

    2010-07-01

    ... District Fireworks Displays. 165.506 Section 165.506 Navigation and Navigable Waters COAST GUARD... § 165.506 Safety Zones; Fifth Coast Guard District Fireworks Displays. (a) Regulations. The following regulations apply to the fireworks safety zones listed in the Table to § 165.506. (1) The general regulations...

  13. Design and construction of an Offner spectrometer based on geometrical analysis of ring fields.

    Science.gov (United States)

    Kim, Seo Hyun; Kong, Hong Jin; Lee, Jong Ung; Lee, Jun Ho; Lee, Jai Hoon

    2014-08-01

    A method to obtain an aberration-corrected Offner spectrometer without ray obstruction is proposed. A new, more efficient spectrometer optics design is suggested in order to increase its spectral resolution. The derivation of a new ring equation to eliminate ray obstruction is based on geometrical analysis of the ring fields for various numerical apertures. The analytical design applying this equation was demonstrated using the optical design software Code V in order to manufacture a spectrometer working in wavelengths of 900-1700 nm. The simulation results show that the new concept offers an analytical initial design taking the least time of calculation. The simulated spectrometer exhibited a modulation transfer function over 80% at Nyquist frequency, root-mean-square spot diameters under 8.6 μm, and a spectral resolution of 3.2 nm. The final design and its realization of a high resolution Offner spectrometer was demonstrated based on the simulation result. The equation and analytical design procedure shown here can be applied to most Offner systems regardless of the wavelength range.

  14. 33 CFR 23.15 - Coast Guard ensign.

    Science.gov (United States)

    2010-07-01

    ... distinctive emblem of the Coast Guard in blue and white is placed with its center on a line with the lower..., the emblem covering a horizontal space of three stripes. [CGFR 57-35, 22 FR 6765, Aug. 22, 1957] ...

  15. Synthesis of ring-13C-labelled and ring-demethylated retinals

    International Nuclear Information System (INIS)

    Courtin, J.M.L.

    1988-01-01

    Efficient synthetic schemes are described for the preparation of the required mono- and di- 13 C labelled retinals based on simple 13 C labelled starting materials. Results from solid-state 13 C-NMR spectroscopic studies of the various ring- 13 C labelled bacteriorhodopsins and rhodopsins are discussed. 404 refs.; 74 figs.; 16 tabs

  16. Major benefits of guarding behavior in subsocial bees: implications for social evolution.

    Science.gov (United States)

    Mikát, Michael; Černá, Kateřina; Straka, Jakub

    2016-10-01

    Parental care is a behavior that increases the growth and survival of offspring, often at a cost to the parents' own survival and/or future reproduction. In this study, we focused on nest guarding, which is one of the most important types of extended parental care; we studied this behavior in two solitary bee species of the genus Ceratina with social ancestors. We performed the experiment of removing the laying female, who usually guards the nest after completing its provisioning, to test the effects of nest guarding on the offspring survival and nest fate. By dissecting natural nests, we found that Ceratina cucurbitina females always guarded their offspring until the offspring reached adulthood. In addition, the females of this species were able to crawl across the nest partitions and inspect the offspring in the brood cells. In contrast, several Ceratina chalybea females guarded their nests until the offspring reached adulthood, but others closed the nest entrance with a plug and deserted the nest. Nests with a low number of provisioned cells were more likely to be plugged and abandoned than nests with a higher number of cells. The female removal experiment had a significantly negative effect on offspring survival in both species. These nests frequently failed due to the attacks of natural enemies (e.g., ants, chalcidoid wasps, and other competing Ceratina bees). Increased offspring survival is the most important benefit of the guarding strategy. The abandonment of a potentially unsuccessful brood might constitute a benefit of the nest plugging behavior. The facultative nest desertion strategy is a derived behavior in the studied bees and constitutes an example of an evolutionary reduction in the extent of parental care.

  17. Semi-algebraic function rings and reflectors of partially ordered rings

    CERN Document Server

    Schwartz, Niels

    1999-01-01

    The book lays algebraic foundations for real geometry through a systematic investigation of partially ordered rings of semi-algebraic functions. Real spectra serve as primary geometric objects, the maps between them are determined by rings of functions associated with the spectra. The many different possible choices for these rings of functions are studied via reflections of partially ordered rings. Readers should feel comfortable using basic algebraic and categorical concepts. As motivational background some familiarity with real geometry will be helpful. The book aims at researchers and graduate students with an interest in real algebra and geometry, ordered algebraic structures, topology and rings of continuous functions.

  18. PEP-X: An Ultimate Storage Ring Based on Fourth-Order Geometric Achromats

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yunhai; Bane, Karl; Hettel, Robert; Nosochkov, Yuri; Wang, Min-Huey; /SLAC

    2012-04-06

    We have designed an 'ultimate' storage ring for the PEP-X light source that achieves the diffraction limited emittances (at 1.5 {angstrom}) of 12 pm-rad in both horizontal and vertical planes with a 4.5-GeV beam. These emittances include the contribution of intrabeam scattering at a nominal current of 200 mA in 3300 bunches. This quality beam in conjunction with a conventional 4-m undulator in a straight section can generate synchrotron radiation having a spectral brightness above 10{sup 22} [photons/s/mm{sup 2}/mrad{sup 2}/0.1% BW] at a 10 keV photon energy. The high coherence at the diffraction limit makes PEP-X competitive with 4th generation light sources based on an energy recovery linac. In addition, the beam lifetime is several hours and the dynamic aperture is large enough to allow off-axis injection. The alignment and stability tolerances, though challenging, are achievable. A ring with all these properties is only possible because of several major advances in mitigating the effects of nonlinear resonances.

  19. Implementering af e-læring ved danske universiteter

    Directory of Open Access Journals (Sweden)

    Birgitte Heiberg

    2005-05-01

    Full Text Available

    Første gang publiceret i UNEV nr. 6: Organisering af e-læring, oktober - december 2005, red. Jørgen Gomme, Birgitte heiberg, Jens Dørup og Ambrosia Hansen. ISSN 1603-5518.

    Lige siden de første computere kom til landet har der været projekter, som tilsigtede at understøtte undervisning og læring ved hjælp af IKT. Understøttelsen har varieret som en bred vifte af forskellige former for medieanvendelse og grader af interaktion. Tilsvarende er diverse former for IKT-støttet undervisning og læring med forskellige betegnelser dukket op: Computer-Based Training (CBT, Computer Assisted Learning (CAL, Computer Supported Collaborative Learning (CSCL, Web-based Learning (WBL, blended learning, online læring, fleksibel læring, fjernundervisning, distribueret og åben uddannelse, m. fl.

  20. Design of a ring resonator-based optical beam forming network for phased array receive antennas

    NARCIS (Netherlands)

    van 't Klooster, J.W.J.R.; Roeloffzen, C.G.H.; Meijerink, Arjan; Zhuang, L.; Marpaung, D.A.I.; van Etten, Wim; Heideman, Rene; Leinse, Arne; Schippers, H.; Verpoorte, J.; Wintels, M.

    2008-01-01

    A novel squint-free ring resonator-based optical beam forming network (OBFN) for phased array antennas (PAA) is proposed. It is intended to provide broadband connectivity to airborne platforms via geostationary satellites. In this paper, we present the design of the OBFN and its control system. Our

  1. Rotating ring-ring electrode theory and experiment

    NARCIS (Netherlands)

    Kuiken, H.K.; Bakkers, E.P.A.M.; Ligthart, H.; Kellyb, J.J.

    2000-01-01

    A model is presented for the rotating ring-ring electrode. Although the electrode is defined by four characteristic lengths, it is shown that the collection efficiency depends on only two dimensionless parameters. A simple relationship between these and the corresponding parameters for the rotating

  2. Superposed Redox Chemistry of Fused Carbon Rings in Cyclooctatetraene-Based Organic Molecules for High-Voltage and High-Capacity Cathodes.

    Science.gov (United States)

    Zhao, Xiaolin; Qiu, Wujie; Ma, Chao; Zhao, Yingqin; Wang, Kaixue; Zhang, Wenqing; Kang, Litao; Liu, Jianjun

    2018-01-24

    Even though many organic cathodes have been developed and have made a significant improvement in energy density and reversibility, some organic materials always generate relatively low voltage and limited discharge capacity because their energy storage mechanism is solely based on redox reactions of limited functional groups [N-O, C═X (X = O, N, S)] linking to aromatic rings. Here, a series of cyclooctatetraene-based (C 8 H 8 ) organic molecules were demonstrated to have electrochemical activity of high-capacity and high-voltage from carbon rings by means of first-principles calculations and electronic structure analysis. Fused molecules of C 8 -C 4 -C 8 (C 16 H 12 ) and C 8 -C 4 -C 8 -C 4 -C 8 (C 24 H 16 ) contain, respectively, four and eight electron-deficient carbons, generating high-capacity by their multiple redox reactions. Our sodiation calculations predict that C 16 H 12 and C 24 H 16 exhibit discharge capacities of 525.3 and 357.2 mA h g -1 at the voltage change from 3.5 to 1.0 V and 3.7 to 1.3 V versus Na + /Na, respectively. Electronic structure analysis reveals that the high voltages are attributed to superposed electron stabilization mechanisms, including double-bond reformation and aromatization from carbon rings. High thermodynamic stability of these C 24 H 16 -based systems strongly suggests feasibility of experimental realization. The present work provides evidence that cyclooctatetraene-based organic molecules fused with the C 4 ring are promising in designing high-capacity and high-voltage organic rechargeable cathodes.

  3. 78 FR 8027 - Safety Zone, Coast Guard Exercise Area, Hood Canal, Washington

    Science.gov (United States)

    2013-02-05

    ... 5, 2012. The Coast Guard received zero comments submitted via regulations.gov and received zero... zero comments from the Small Business Administration on this rule. The Coast Guard certifies under 5 U... more in any one year. Though this rule will not result in such an expenditure, we do discuss the...

  4. 46 CFR 159.007-7 - Application for acceptance for production inspections and tests: Coast Guard action.

    Science.gov (United States)

    2010-10-01

    ... and tests: Coast Guard action. 159.007-7 Section 159.007-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL APPROVAL....007-7 Application for acceptance for production inspections and tests: Coast Guard action. (a) From...

  5. Meeting the Organizational Needs of the National Guard as Part of Transformation to the Future Force

    National Research Council Canada - National Science Library

    Wong, Martha

    2005-01-01

    .... They must build and maintain U.S. defenses beyond challenge. As part of the total military force and to comply with the National Security Strategy, the National Guard also must transform from the Guard of the past to the Guard of the future...

  6. 5.0 kV breakdown-voltage vertical GaN p-n junction diodes

    Science.gov (United States)

    Ohta, Hiroshi; Hayashi, Kentaro; Horikiri, Fumimasa; Yoshino, Michitaka; Nakamura, Tohru; Mishima, Tomoyoshi

    2018-04-01

    A high breakdown voltage of 5.0 kV has been achieved for the first time in vertical GaN p-n junction diodes by using our newly developed guard-ring structures. A resistance device was inserted between the main diode portion and the guard-ring portion in a ring-shaped p-n diode to generate a voltage drop over the resistance device by leakage current flowing through the guard-ring portion under negatively biased conditions before breakdown. The voltage at the outer mesa edge of the guard-ring portion, where the electric field intensity is highest and the destructive breakdown usually occurs, is decreased by the voltage drop, so the electric field concentration in the portion is reduced. By adopting this structure, the breakdown voltage (V B) is raised by about 200 V. Combined with a low measured on-resistance (R on) of 1.25 mΩ cm2, Baliga’s figure of merit (V\\text{B}2/R\\text{on}) was as high as 20 GW/cm2.

  7. Ring artifact correction for high-resolution micro CT

    International Nuclear Information System (INIS)

    Kyriakou, Yiannis; Prell, Daniel; Kalender, Willi A

    2009-01-01

    In high-resolution micro CT using flat detectors (FD), imperfect or defect detector elements may cause concentric-ring artifacts due to their continuous over- or underestimation of attenuation values, which often disturb image quality. We here present a dedicated image-based ring artifact correction method for high-resolution micro CT, based on median filtering of the reconstructed image and working on a transformed version of the reconstructed images in polar coordinates. This post-processing method reduced ring artifacts in the reconstructed images and improved image quality for phantom and in in vivo scans. Noise and artifacts were reduced both in transversal and in multi-planar reformations along the longitudinal axis. (note)

  8. System and Circuit Design Aspects for CMOS Wireless Handset Receivers

    DEFF Research Database (Denmark)

    Mikkelsen, Jan H.

    and it is shown that, depending on the size of the guard-ring, the Q-value reduction is found to be significantly reduced at RF frequencies. In continuation of this, various coupling effects for CMOS on-chip co-planar spiral inductors are presented. Simple guard-rings are shown to improve isolation between...... closely spaced adjacent inductors by approximately 10-15dB. At larger distances the gain of having a guard-ring reduces and eventually the gain reduces to zero dB. For modeling purposes an extended lumped element model is proposed and found to fit very well with crosstalk measurements....

  9. DEGRADATION OF MAGNET EPOXY AT NSLS X-RAY RING.

    Energy Technology Data Exchange (ETDEWEB)

    HU,J.P.; ZHONG,Z.; HAAS,E.; HULBERT,S.; HUBBARD,R.

    2004-05-24

    Epoxy resin degradation was analyzed for NSLS X-ring magnets after two decades of 2.58-2.8 GeV continuous electron-beam operation, based on results obtained from thermoluminescent dosimeters irradiated along the NSLS ring and epoxy samples irradiated at the beamline target location. A Monte Carlo-based particle transport code, MCNP, was utilized to verify the dose from synchrotron radiation distributed along the axial- and transverse-direction in a ring model, which simulates the geometry of a ring quadrupole magnet and its central vacuum chamber downstream of the bending-magnet photon ports. The actual life expectancy of thoroughly vacuum baked-and-cured epoxy resin was estimated from radiation tests on similar polymeric materials using a radiation source developed for electrical insulation and mechanical structure studies.

  10. Bernstein instability driven by thermal ring distribution

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Peter H., E-mail: yoonp@umd.edu [Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742 (United States); School of Space Research, Kyung Hee University, Yongin-Si, Gyeonggi-Do 446-701 (Korea, Republic of); Hadi, Fazal; Qamar, Anisa [Institute of Physics and Electronics, University of Peshawar, Peshawar 25000 (Pakistan)

    2014-07-15

    The classic Bernstein waves may be intimately related to banded emissions detected in laboratory plasmas, terrestrial, and other planetary magnetospheres. However, the customary discussion of the Bernstein wave is based upon isotropic thermal velocity distribution function. In order to understand how such waves can be excited, one needs an emission mechanism, i.e., an instability. In non-relativistic collision-less plasmas, the only known Bernstein wave instability is that associated with a cold perpendicular velocity ring distribution function. However, cold ring distribution is highly idealized. The present Brief Communication generalizes the cold ring distribution model to include thermal spread, so that the Bernstein-ring instability is described by a more realistic electron distribution function, with which the stabilization by thermal spread associated with the ring distribution is demonstrated. The present findings imply that the excitation of Bernstein waves requires a sufficiently high perpendicular velocity gradient associated with the electron distribution function.

  11. Bernstein instability driven by thermal ring distribution

    International Nuclear Information System (INIS)

    Yoon, Peter H.; Hadi, Fazal; Qamar, Anisa

    2014-01-01

    The classic Bernstein waves may be intimately related to banded emissions detected in laboratory plasmas, terrestrial, and other planetary magnetospheres. However, the customary discussion of the Bernstein wave is based upon isotropic thermal velocity distribution function. In order to understand how such waves can be excited, one needs an emission mechanism, i.e., an instability. In non-relativistic collision-less plasmas, the only known Bernstein wave instability is that associated with a cold perpendicular velocity ring distribution function. However, cold ring distribution is highly idealized. The present Brief Communication generalizes the cold ring distribution model to include thermal spread, so that the Bernstein-ring instability is described by a more realistic electron distribution function, with which the stabilization by thermal spread associated with the ring distribution is demonstrated. The present findings imply that the excitation of Bernstein waves requires a sufficiently high perpendicular velocity gradient associated with the electron distribution function

  12. Evolution of the US Coast Guard's oil identification system

    International Nuclear Information System (INIS)

    Hendrick, M.S.; Reilly, T.R.

    1993-01-01

    The U.S. Coast Guard, tasked with the development of open-quotes procedures and techniques to be employed in identifying ... oil and hazardous substances . . . open-quotes by the 1972 Federal Water Pollution Control Act (FWPCA), developed the Oil Identification System (OIS). The OIS was based on four analytical laboratory techniques: infrared (IR) and fluorescence (FL) spectroscopy, gas chromatography (GC), and thin- layer chromatography (TLC). A Central Oil Identification Laboratory (COIL) began operation in 1977, and field laboratories (FOILS) using two of the techniques (FL and TLC) were established in many Marine Safety Offices to screen possible sources. Development of the OIS was documented in two formal reports, in 1974 and 1977. The current implementation of the OIS at COIL is still based on a multimethod approach, but it incorporates today's state-of-the-art technology and responds to the current needs of the Coast Guard. One pervasive force for change has been the affordability of computers. The rapid development of computerized instruments has resulted in improvements in the performance, ruggedness, and prices of analytical laboratory equipment. All the instruments in the authors' laboratory at the present time are interfaced to or have internal computerized data-handling systems. Fourier-transform infrared spectrometers (FTIR) have replaced older mechanically scanning, dispersive IR instruments. High-performance liquid chromatography (HPLC) has replaced TLC completely. A gas chromatography/mass spectrometer (GC/MS), a room-size research tool in 1977, sits on a benchtop in the laboratory today, and a standard method for oil identification is being developed for this technique. Laboratory strategies are now based on finding the most efficient use of resources, as rapid response times are not necessary in all cases. It may also be possible in the near future to resume field testing

  13. Kayser-Fleischer Rings

    Science.gov (United States)

    ... Support Contacts Lab Tracker/Copper Calculator Stories Programs & Research ... About Everything you need to know about Wilson Disease Kayser-Fleischer Rings Definition Kayser-Fleischer Ring: Clinical sign. Brownish-yellow ring visible around the corneo- ...

  14. On semantics and applications of guarded recursion

    DEFF Research Database (Denmark)

    Bizjak, Aleš

    2016-01-01

    denotational model and a logic for reasoning about program equivalence. In the last three chapters we study syntax and semantics of a dependent type theory with a family of later modalities indexed by the set of clocks, and clock quantifiers. In the fourth and fifth chapters we provide two model constructions......In this dissertation we study applications and semantics of guarded recursion, which is a method for ensuring that self-referential descriptions of objects define a unique object. The first two chapters are devoted to applications. We use guarded recursion, first in the form of explicit step......-indexing and then in the form of the internal language of particular sheaf topos, to construct logical relations for reasoning about contextual approximation of probabilistic and nondeterministic programs. These logical relations are sound and complete and useful for showing a range of example equivalences. In the third...

  15. Denotational semantics in Synthetic Guarded Domain Theory

    DEFF Research Database (Denmark)

    Paviotti, Marco

    In functional programming, features such as recursion, recursive types and general references are central. To define semantics of this kind of languages one needs to come up with certain definitions which may be non-trivial to show well-defined. This is because they are circular. Domain theory has...... been used to solve this kind of problems for specific languages, unfortunately, this technique does not scale for more featureful languages, which prevented it from being widely used. Step-indexing is a more general technique that has been used to break circularity of definitions. The idea is to tweak...... the definition by adding a well- founded structure that gives a handle for recursion. Guarded dependent Type Theory (gDTT) is a type theory which implements step-indexing via a unary modality used to guard recursive definitions. Every circular definition is well-defined as long as the recursive variable...

  16. Novel Fiber-Optic Ring Acoustic Emission Sensor

    Directory of Open Access Journals (Sweden)

    Peng Wei

    2018-01-01

    Full Text Available Acoustic emission technology has been applied to many fields for many years. However, the conventional piezoelectric acoustic emission sensors cannot be used in extreme environments, such as those with heavy electromagnetic interference, high pressure, or strong corrosion. In this paper, a novel fiber-optic ring acoustic emission sensor is proposed. The sensor exhibits high sensitivity, anti-electromagnetic interference, and corrosion resistance. First, the principle of a novel fiber-optic ring sensor is introduced. Different from piezoelectric and other fiber acoustic emission sensors, this novel sensor includes both a sensing skeleton and a sensing fiber. Second, a heterodyne interferometric demodulating method is presented. In addition, a fiber-optic ring sensor acoustic emission system is built based on this method. Finally, fiber-optic ring acoustic emission experiments are performed. The novel fiber-optic ring sensor is glued onto the surface of an aluminum plate. The 150 kHz standard continuous sinusoidal signals and broken lead signals are successfully detected by the novel fiber-optic ring acoustic emission sensor. In addition, comparison to the piezoelectric acoustic emission sensor is performed, which shows the availability and reliability of the novel fiber-optic ring acoustic emission sensor. In the future, this novel fiber-optic ring acoustic emission sensor will provide a new route to acoustic emission detection in harsh environments.

  17. Bimodality and the formation of Saturn's ring particles

    International Nuclear Information System (INIS)

    Gehrels, T.

    1980-01-01

    The F ring appears to have an outer and an inner rim, with only the latter observed by the imaging photopolarimeter (IPP) on the Pioneer Saturn spacecraft. The inside of the G ring, near 2.49 R/sub S/, may also be seen in the optical data. 1979S1 is red as well as dark. The light scattered through the B ring is noticeably red. The A ring has a dense outer rim. The Cassini Division and the French Division (Dollfus Division) have a dark gap near their centers. The C ring becomes weaker toward the center such that outer, middle, and inner C rings can be recognized. The Pioneer and earth-based observations are explained with a model for the B and A rings to some extent of a bimodal size distributions of particles; the larger ones may be original accretions, while small debris diffuses inward through the Cassini Division and the C ring. During the formation of the ring system, differential gravitation allowed only silicaceous grains of higher density (rho> or approx. =3 g cm -3 ) to coagulate. These serve as interstitial cores for snowy carbonaceous grains, between the times of accretion from interplanetary cometary grains and liberation by collision followed by diffusion inward to Saturn and final evaporation

  18. Findings From the National Machine Guarding Program?A Small Business Intervention

    OpenAIRE

    Parker, David L.; Yamin, Samuel C.; Xi, Min; Brosseau, Lisa M.; Gordon, Robert; Most, Ivan G.; Stanley, Rodney

    2016-01-01

    Objectives: The purpose of this nationwide intervention was to improve machine safety in small metal fabrication businesses (3 to 150 employees). The failure to implement machine safety programs related to guarding and lockout/tagout (LOTO) are frequent causes of Occupational Safety and Health Administration (OSHA) citations and may result in serious traumatic injury. Methods: Insurance safety consultants conducted a standardized evaluation of machine guarding, safety programs, and LOTO. Busi...

  19. Comparison of Heavy-Duty Scuffing Behavior between Chromium-Based Ceramic Composite and Nickel-Chromium-Molybdenum-Coated Ring Sliding against Cast Iron Liner under Starvation

    Directory of Open Access Journals (Sweden)

    Yan Shen

    2017-10-01

    Full Text Available A running-in and starved lubrication experiment is designed to investigate the heavy-duty scuffing behavior of piston ring coatings against cast iron (Fe cylinder liner using the piston ring reciprocating liner test rig. The scuffing resistance of the piston ring with the chromium-based ceramic composite coating (CKS, and that with the thermally sprayed nickel-chromium-molybdenum coating (NCM is compared at different nominal pressures (40~100 MPa and temperatures (180~250 °C. With the failure time as a criterion, the rank order is as follows: NCM/Fe > CKS/Fe. Before the scoring occurs at the interface of the piston ring and cylinder liner (PRCL, the cast iron liner enters into a “polish wear” stage, and iron-based adhesive materials begin to form on the piston ring surface. With the macroscopic adhesion formation, the plastic shearing cycle causes surface damages mainly due to abrasive effects for the CKS/Fe pairs and adhesive effects for the NCM/Fe pairs.

  20. RF Spectrum Sensing Based on an Overdamped Nonlinear Oscillator Ring for Cognitive Radios

    Directory of Open Access Journals (Sweden)

    Zhi-Ling Tang

    2016-06-01

    Full Text Available Existing spectrum-sensing techniques for cognitive radios require an analog-to-digital converter (ADC to work at high dynamic range and a high sampling rate, resulting in high cost. Therefore, in this paper, a spectrum-sensing method based on a unidirectionally coupled, overdamped nonlinear oscillator ring is proposed. First, the numerical model of such a system is established based on the circuit of the nonlinear oscillator. Through numerical analysis of the model, the critical condition of the system’s starting oscillation is determined, and the simulation results of the system’s response to Gaussian white noise and periodic signal are presented. The results show that once the radio signal is input into the system, it starts oscillating when in the critical region, and the oscillating frequency of each element is fo/N, where fo is the frequency of the radio signal and N is the number of elements in the ring. The oscillation indicates that the spectrum resources at fo are occupied. At the same time, the sampling rate required for an ADC is reduced to the original value, 1/N. A prototypical circuit to verify the functionality of the system is designed, and the sensing bandwidth of the system is measured.

  1. Preparation for electron ring - plasma ring merging experiments in RECE-MERGE

    International Nuclear Information System (INIS)

    Taggart, D.; Sekiguchi, A.; Fleischmann, H.H.

    1986-01-01

    The formation of a mixed-CT using relativistic electron rings and gun-produced plasma rings by MERGE-ing them axially is simulated. This process is similar to the axial stacking of relativistic electron rings in RECE-Christa. The results of their first plasm production experiment are reported here. After study of the gun-produced plasma's properties is completed, the gun will be mounted at the downstream end of the vacuum tank and the source of relativistic electron rings will be at the upstream end. The two rings, formed at opposite ends of the tank, will be translated axially and merged

  2. On the nonlinear modeling of ring oscillators

    KAUST Repository

    Elwakil, Ahmed S.

    2009-06-01

    We develop higher-order nonlinear models of three-stage and five-stage ring oscillators based on a novel inverter model. The oscillation condition and oscillation frequency are derived and compared to classical linear model analysis. Two important special cases for five-stage ring oscillators are also studied. Numerical simulations are shown. © 2009 World Scientific Publishing Company.

  3. On the nonlinear modeling of ring oscillators

    KAUST Repository

    Elwakil, Ahmed S.; Salama, Khaled N.

    2009-01-01

    We develop higher-order nonlinear models of three-stage and five-stage ring oscillators based on a novel inverter model. The oscillation condition and oscillation frequency are derived and compared to classical linear model analysis. Two important special cases for five-stage ring oscillators are also studied. Numerical simulations are shown. © 2009 World Scientific Publishing Company.

  4. Mate guarding in the Seychelles warbler is energetically costly and adjusted to paternity risk.

    Science.gov (United States)

    Komdeur, J

    2001-10-22

    Males may increase their fitness through extra-pair copulations (copulations outside the pair bond) that result in extra-pair fertilizations, but also risk lost paternity when they leave their own mate unguarded. The fitness costs of cuckoldry for Seychelles warblers (Acrocephalus sechellensis) are considerable because warblers have a single-egg clutch and, given the short breeding season, no time for a successful replacement clutch. Neighbouring males are the primary threat to a male's genetic paternity. Males minimize their loss of paternity by guarding their mates to prevent them from having extra-pair copulations during their fertile period. Here, I provide experimental evidence that mate-guarding behaviour is energetically costly and that the expression of this trade-off is adjusted to paternity risk (local male density). Free-living males that were induced to reduce mate guarding spent significantly more time foraging and gained significantly better body condition than control males. The larger the reduction in mate guarding, the more pronounced was the increase in foraging and body condition (accounting for food availability). An experimental increase in paternity risk resulted in an increase in mate-guarding intensity and a decrease in foraging and body condition, and vice versa. This is examined using both cross-sectional and longitudinal data. This study on the Seychelles warbler offers experimental evidence that mate guarding is energetically costly and adjusted to paternity risk.

  5. Fourth-generation storage rings

    International Nuclear Information System (INIS)

    Galayda, J. N.

    1999-01-01

    It seems clear that a linac-driven free-electron laser is the accepted prototype of a fourth-generation facility. This raises two questions: can a storage ring-based light source join the fourth generation? Has the storage ring evolved to its highest level of performance as a synchrotrons light source? The answer to the second question is clearly no. The author thinks the answer to the first question is unimportant. While the concept of generations has been useful in motivating thought and effort towards new light source concepts, the variety of light sources and their performance characteristics can no longer be usefully summed up by assignment of a ''generation'' number

  6. Factors influencing resident's decision to reside in gated and guarded community

    Science.gov (United States)

    Shamsudin, Zarina; Shamsudin, Shafiza; Zainal, Rozlin

    2017-10-01

    Gated communities are residential areas developed with restricted access with strictly controlled entrances and surrounded by a close perimeter of wall or fences. Developers, conscious of the need to fulfill the requirement of living in modern and sophisticated lifestyle and gated properties become the trend and mushroomed over the past decade. Nowadays, it is obvious that gated and guarded communities become almost a dominant feature of Malaysia housing development projects. The focus of this paper is to identify the factors contribute resident's decision to reside in gated and guarded community and to study social interaction among gated communities' residents. 150 questionnaires were distributed to the residents of selected gated and guarded community area in order to achieve the objectives and analyzed by using Statistical Package for Social Science (SPSS) and descriptive analysis. The result was tabulated and presented in charts and graphs for a clear and better understanding. The five main factors contribute to resident decision to reside in gated communities were identified and ranked; there are privacy, security, location, lifestyle and prestige. Besides, the residents are feeling neutral towards the facilities and services provided in their gated and guarded residential area. A comprehensive improvement towards the facilities and services is needed to reach higher satisfaction from the residents.

  7. From Darkness to Light: Posttraumatic Growth among Recently Deployed Army National Guard Soldiers

    Science.gov (United States)

    2013-02-14

    Stress and Associated Functioning of Army National Guard Following Exposure to Iraq Warzone Trauma,” Traumatology 14 (2008): 51. 9. Army National...Associated Functioning of Army National Guard Following Exposure to Iraq Warzone Trauma.” Traumatology , 14 (2008): 51–56. Ouimette, Paige, Dawne Vogt

  8. EPA Region 1 Coast Guard Jurisdictional Boundary - Polygons

    Data.gov (United States)

    U.S. Environmental Protection Agency — Jurisdictional boundary between EPA and Coast Guard for EPA Region I. Created from 1:100000 USGS DLGs with greater detail drawn from 1:24000 commercial street data...

  9. EPA Region 1 Coast Guard Jurisdictional Boundary - Arcs

    Data.gov (United States)

    U.S. Environmental Protection Agency — Jurisdictional boundary between EPA and Coast Guard for EPA Region I. Created from 1:100000 USGS DLGs with greater detail drawn from 1:24000 commercial street data...

  10. Surface emitting ring quantum cascade lasers for chemical sensing

    Science.gov (United States)

    Szedlak, Rolf; Hayden, Jakob; Martín-Mateos, Pedro; Holzbauer, Martin; Harrer, Andreas; Schwarz, Benedikt; Hinkov, Borislav; MacFarland, Donald; Zederbauer, Tobias; Detz, Hermann; Andrews, Aaron Maxwell; Schrenk, Werner; Acedo, Pablo; Lendl, Bernhard; Strasser, Gottfried

    2018-01-01

    We review recent advances in chemical sensing applications based on surface emitting ring quantum cascade lasers (QCLs). Such lasers can be implemented in monolithically integrated on-chip laser/detector devices forming compact gas sensors, which are based on direct absorption spectroscopy according to the Beer-Lambert law. Furthermore, we present experimental results on radio frequency modulation up to 150 MHz of surface emitting ring QCLs. This technique provides detailed insight into the modulation characteristics of such lasers. The gained knowledge facilitates the utilization of ring QCLs in combination with spectroscopic techniques, such as heterodyne phase-sensitive dispersion spectroscopy for gas detection and analysis.

  11. Ring-Resonator/Sol-Gel Interferometric Immunosensor

    Science.gov (United States)

    Bearman, Gregory; Cohen, David

    2007-01-01

    A proposed biosensing system would be based on a combination of (1) a sensing volume containing antibodies immobilized in a sol-gel matrix and (2) an optical interferometer having a ring resonator configuration. The antibodies would be specific to an antigen species that one seeks to detect. In the ring resonator of the proposed system, light would make multiple passes through the sensing volume, affording greater interaction length and, hence, greater antibody- detection sensitivity.

  12. 76 FR 66239 - Safety Zones; Fireworks Displays Within the Fifth Coast Guard District

    Science.gov (United States)

    2011-10-26

    ...-AA00 Safety Zones; Fireworks Displays Within the Fifth Coast Guard District AGENCY: Coast Guard, DHS... safety zones established for fireworks displays at various locations within the geographic boundary of... maritime public from the hazards posed by fireworks displays. Entry into or movement within these proposed...

  13. Amplitude-modulated fiber-ring laser

    DEFF Research Database (Denmark)

    Caputo, J. G.; Clausen, Carl A. Balslev; Sørensen, Mads Peter

    2000-01-01

    Soliton pulses generated by a fiber-ring laser are investigated by numerical simulation and perturbation methods. The mathematical modeling is based on the nonlinear Schrödinger equation with perturbative terms. We show that active mode locking with an amplitude modulator leads to a self......-starting of stable solitonic pulses from small random noise, provided the modulation depth is small. The perturbative analysis leads to a nonlinear coupled return map for the amplitude, phase, and position of the soliton pulses circulating in the fiber-ring laser. We established the validity of this approach...

  14. Light-Ring Stability for Ultracompact Objects

    Science.gov (United States)

    Cunha, Pedro V. P.; Berti, Emanuele; Herdeiro, Carlos A. R.

    2017-12-01

    We prove the following theorem: axisymmetric, stationary solutions of the Einstein field equations formed from classical gravitational collapse of matter obeying the null energy condition, that are everywhere smooth and ultracompact (i.e., they have a light ring) must have at least two light rings, and one of them is stable. It has been argued that stable light rings generally lead to nonlinear spacetime instabilities. Our result implies that smooth, physically and dynamically reasonable ultracompact objects are not viable as observational alternatives to black holes whenever these instabilities occur on astrophysically short time scales. The proof of the theorem has two parts: (i) We show that light rings always come in pairs, one being a saddle point and the other a local extremum of an effective potential. This result follows from a topological argument based on the Brouwer degree of a continuous map, with no assumptions on the spacetime dynamics, and, hence, it is applicable to any metric gravity theory where photons follow null geodesics. (ii) Assuming Einstein's equations, we show that the extremum is a local minimum of the potential (i.e., a stable light ring) if the energy-momentum tensor satisfies the null energy condition.

  15. 76 FR 28795 - Privacy Act of 1974; Department of Homeland Security United States Coast Guard-024 Auxiliary...

    Science.gov (United States)

    2011-05-18

    ... 1974; Department of Homeland Security United States Coast Guard-024 Auxiliary Database System of... Security/United States Coast Guard-024 Auxiliary Database (AUXDATA) System of Records.'' This system of...: United States Coast Guard Auxiliary Database (AUXDATA). Security classification: Unclassified. System...

  16. Response capabilities of the National Guard: a focus on domestic disaster medical response.

    Science.gov (United States)

    Bochicchio, Daniel

    2010-01-01

    The National Guard has a 373-year history of responding to the nation's call to duty for service both at home and abroad (The National Guard Bureau Web site: Available at http://www.ngb.army.mil/default. aspx.). The National Guard (NG) is a constitutionally unique organization (United States Constitution, US Government Printing Office Web site: Available at http://www.gpoaccess.gov/constitution/index.html.). Today's Guard conducts domestic disaster response and civilian assistance missions on a daily basis. Yet, the NG's role, mission, and capabilities are not well-known or understood. The National Response Framework (NRF) places significant responsibility on the local and state disaster planners (Department of Homeland Security: National Response Framework. US Department of Homeland Security, Washington, DC, January 2008). The public health professionals are an integral component of the disaster planning community. It is critical that the public health community be knowledgeable of types and capabilities of all the response assets at their disposal.

  17. New design of a triplexer using ring resonator integrated with directional coupler based on photonic crystals

    Science.gov (United States)

    Wu, Yaw-Dong; Shih, Tien-Tsorng; Lee, Jian-Jang

    2009-11-01

    In this paper, we proposed the design of directional coupler integrated with ring resonator based on two-dimensional photonic crystals (2D PCs) to develop a triplexer filter. It can be widely used as the fiber access network element for multiplexer-demultiplexer wavelength selective in fiber-to-the-home (FTTH) communication systems. The directional coupler is chosen to separate the wavelengths of 1490nm and 1310nm. The ring resonator separates the wavelength of 1550nm. The transmission efficiency is larger than 90%. Besides, the total size of propose triplexer is only 19μm×12μm. We present simulation results using the finite-difference time-domain (FDTD) method for the proposed structure.

  18. 78 FR 55214 - Annual Marine Events in the Eighth Coast Guard District, Sabine River; Orange, TX

    Science.gov (United States)

    2013-09-10

    ... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 100 [Docket No. USCG-2013-0723] Annual Marine Events in the Eighth Coast Guard District, Sabine River; Orange, TX AGENCY: Coast Guard, DHS... Neches River in Orange, TX from 3 p.m. on September 20, 2013, through 6 p.m. on September 22, 2013. This...

  19. 77 FR 47519 - Annual Marine Events in the Eighth Coast Guard District, Sabine River; Orange, TX

    Science.gov (United States)

    2012-08-09

    ... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 100 [Docket No. USCG-2012-0656] Annual Marine Events in the Eighth Coast Guard District, Sabine River; Orange, TX AGENCY: Coast Guard, DHS... Regulations for the S.P.O.R.T. Power Boat Neches River in Orange, TX from 3 p.m. on September 21, 2012...

  20. 46 CFR 50.10-30 - Coast Guard number.

    Science.gov (United States)

    2010-10-01

    ... boilers and pressure vessels. (c) The Coast Guard number is comprised of the following: (1) Three capital... St. Louis. STB Sturgeon Bay. TAM Tampa. TOL Toledo. VAL Valdez. WNC Wilmington, NC. [CGFR 68-82, 33...

  1. Stable CSR in storage rings: A model

    International Nuclear Information System (INIS)

    Sannibale, Fernando; Byrd, John M.; Loftsdottir, Agusta; Venturini, Marco; Abo-Bakr, Michael; Feikes, Jorge; Holldack, Karsten; Kuske, Peter; Wustefeld, Godehart; Hubers, Heinz-Willerm; Warnock, Robert

    2005-01-01

    A comprehensive historical view of the work done on coherent synchrotron radiation (CSR) in storage rings is given in reference [1]. Here we want just to point out that even if the issue of CSR in storage rings was already discussed over 50 years ago, it is only recently that a considerable number of observations have been reported. In fact, intense bursts of coherent synchrotron radiation with a stochastic character were measured in the terahertz frequency range, at several synchrotron light source storage rings [2-8]. It has been shown [8-11], that this bursting emission of CSR is associated with a single bunch instability, usually referred as microbunching instability (MBI), driven by the fields of the synchrotron radiation emitted by the bunch itself. Of remarkably different characteristics was the CSR emission observed at BESSY II in Berlin, when the storage ring was tuned into a special low momentum compaction mode [12, 13]. In fact, the emitted radiation was not the quasi-random bursting observed in the other machines, but a powerful and stable flux of broadband CSR in the terahertz range. This was an important result, because it experimentally demonstrated the concrete possibility of constructing a stable broadband source with extremely high power in the terahertz region. Since the publication of the first successful experiment using the ring as a CSR source [14], BESSY II has regular scheduled user s shifts dedicated to CSR experiments. At the present time, several other laboratories are investigating the possibility of a CSR mode of operation [15-17] and a design for a new ring optimized for CSR is at an advanced stage [18]. In what follows, we describe a model that first accounts for the BESSY II observations and then indicates that the special case of BESSY II is actually quite general and typical when relativistic electron storage rings are tuned for short bunches. The model provides a scheme for predicting and optimizing the performance of ring-based

  2. Stable CSR in Storage Rings: A Model

    International Nuclear Information System (INIS)

    Sannibale, F.

    2005-01-01

    A comprehensive historical view of the work done on coherent synchrotron radiation (CSR) in storage rings is given in reference [1]. Here we want just to point out that even if the issue of CSR in storage rings was already discussed over 50 years ago, it is only recently that a considerable number of observations have been reported. In fact, intense bursts of coherent synchrotron radiation with a stochastic character were measured in the terahertz frequency range, at several synchrotron light source storage rings [2-8]. It has been shown [8-11], that this bursting emission of CSR is associated with a single bunch instability, usually referred as microbunching instability (MBI), driven by the fields of the synchrotron radiation emitted by the bunch itself. Of remarkably different characteristics was the CSR emission observed at BESSY II in Berlin, when the storage ring was tuned into a special low momentum compaction mode [12, 13]. In fact, the emitted radiation was not the quasi-random bursting observed in the other machines, but a powerful and stable flux of broadband CSR in the terahertz range. This was an important result, because it experimentally demonstrated the concrete possibility of constructing a stable broadband source with extremely high power in the terahertz region. Since the publication of the first successful experiment using the ring as a CSR source [14], BESSY II has regular scheduled user's shifts dedicated to CSR experiments. At the present time, several other laboratories are investigating the possibility of a CSR mode of operation [15-17] and a design for a new ring optimized for CSR is at an advanced stage [18]. In what follows, we describe a model that first accounts for the BESSY II observations and then indicates that the special case of BESSY II is actually quite general and typical when relativistic electron storage rings are tuned for short bunches. The model provides a scheme for predicting and optimizing the performance of ring-based

  3. Groups, rings, modules

    CERN Document Server

    Auslander, Maurice

    2014-01-01

    This classic monograph is geared toward advanced undergraduates and graduate students. The treatment presupposes some familiarity with sets, groups, rings, and vector spaces. The four-part approach begins with examinations of sets and maps, monoids and groups, categories, and rings. The second part explores unique factorization domains, general module theory, semisimple rings and modules, and Artinian rings. Part three's topics include localization and tensor products, principal ideal domains, and applications of fundamental theorem. The fourth and final part covers algebraic field extensions

  4. Saturn's Rings Edge-on

    Science.gov (United States)

    1995-01-01

    In one of nature's most dramatic examples of 'now-you see-them, now-you-don't', NASA's Hubble Space Telescope captured Saturn on May 22, 1995 as the planet's magnificent ring system turned edge-on. This ring-plane crossing occurs approximately every 15 years when the Earth passes through Saturn's ring plane.For comparison, the top picture was taken by Hubble on December 1, 1994 and shows the rings in a more familiar configuration for Earth observers.The bottom picture was taken shortly before the ring plane crossing. The rings do not disappear completely because the edge of the rings reflects sunlight. The dark band across the middle of Saturn is the shadow of the rings cast on the planet (the Sun is almost 3 degrees above the ring plane.) The bright stripe directly above the ring shadow is caused by sunlight reflected off the rings onto Saturn's atmosphere. Two of Saturn's icy moons are visible as tiny starlike objects in or near the ring plane. They are, from left to right, Tethys (slightly above the ring plane) and Dione.This observation will be used to determine the time of ring-plane crossing and the thickness of the main rings and to search for as yet undiscovered satellites. Knowledge of the exact time of ring-plane crossing will lead to an improved determination of the rate at which Saturn 'wobbles' about its axis (polar precession).Both pictures were taken with Hubble's Wide Field Planetary Camera 2. The top image was taken in visible light. Saturn's disk appears different in the bottom image because a narrowband filter (which only lets through light that is not absorbed by methane gas in Saturn's atmosphere) was used to reduce the bright glare of the planet. Though Saturn is approximately 900 million miles away, Hubble can see details as small as 450 miles across.The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science.This image and other images and

  5. 77 FR 28766 - Eighth Coast Guard District Annual Marine Events and Safety Zones

    Science.gov (United States)

    2012-05-16

    .... SUMMARY: On March 1, 2012, the Coast Guard published a direct final rule, amending and updating its... effect as scheduled. The Coast Guard is also correcting two entries in this rule through technical... event's date, location, and the resulting special local regulation remain the same. The next occurrence...

  6. A Feeding Strategy in Inner L-Shape Ring Hot Rolling Process

    Directory of Open Access Journals (Sweden)

    Wen Meng

    2017-01-01

    Full Text Available In order to make the inner L-shape ring polling process with a closed die structure (ILRRCDS on the top and bottom of the driven roll stable, at first, this paper established the mathematical model for ILRRCDS. Then, the plastic penetration and biting-in conditions for ILRRCDS were deduced based on plain ring rolling theory. Moreover, a feeding strategy that can realize a constant growth of the ring’s outer radius was proposed and the reasonable value ranges of the feed rate of the mandrel were determined. The numerical simulation model for ILRRCDS is established based on ABAQUS software. Finally, the equivalent plastic strain (PEEQ and temperature distributions of rolled ring were obtained. The results indicated that the proposed feeding strategy can realize a stable ILRRCDS. At the end of ILRRCDS, the PEEQ at the inner radius surface of the ring is maximum, the PEEQ at the outer radius surface of the ring takes the second place, and the PEEQ at the middle part of ring is minimum. With the increase of rolling time, the higher temperature zone of the rolled ring gradually moves from the center part of the ring to the “inner corner zone” of the ring.

  7. Ring-opening of gamma-valerolactone with amino compounds

    NARCIS (Netherlands)

    Chalid, Mochamad; Heeres, Hero J.; Broekhuis, Antonius A.

    2012-01-01

    Diols obtained by the ring-opening of biomass-based gamma-valerolactone (GVL) are potentially valuable building blocks that can be used as precursors in the manufacture of green polymers and resins. We report here a study on the ring-opening of GVL through adding amine compounds. The reactivity of

  8. MATLAB based beam orbit correction system of HLS storage ring

    International Nuclear Information System (INIS)

    Ding Shichuan; Liu Gongfa; Xuan Ke; Li Weimin; Wang Lin; Wang Jigang; Li Chuan; Bao Xun; Guo Weiqun

    2006-01-01

    The distortion of closed orbit usually causes much side effect which is harmful to synchrotron radiation source such as HLS, so it is necessary to correct the distortion of closed orbit. In this paper, the correction principle, development procedure and test of MATLAB based on beam orbit correction system of HLS storage ring are described. The correction system is consisted of the beam orbit measure system, corrector magnet system and the control system, and the beam orbit correction code based on MATLAB is working on the operation interface. The data of the beam orbit are analyzed and calculated firstly, and then the orbit is corrected by changing corrector strength via control system. The test shows that the distortion of closed orbit is from max 4.468 mm before correction to max 0.299 mm after correction as well as SDEV is from 2.986 mm to 0.087 mm. So the correction system reaches the design goal. (authors)

  9. Micro-discharge noise and radiation damage of silicon microstrip sensors

    International Nuclear Information System (INIS)

    Ohsugi, T.; Iwata, Y.; Ohyama, H.; Ohmoto, T.; Yoshikawa, M.; Handa, T.; Kurino, K.; Fujita, K.; Kitabayashi, H.; Tamura, N.; Hatakenaka, T.; Maeohmichi, M.; Takahata, M.; Nakao, M.; Iwasaki, H.; Kohriki, T.; Terada, S.; Unno, Y.; Takashima, R.; Yamamoto, K.; Yamamura, K.

    1996-01-01

    We have examined experimentally some existing ideas for improving the radiation hardness of silicon microstrip sensors. We confirm that the extended electrode and the deep implant-strip proposed on the basis of simulation studies works effectively to suppress micro-discharge as well as junction breakdown of the bias or guard ring. For an integrated coupling capacitor a double layer structure of SiO 2 and Si 3 N 4 provides better radiation hardness than that of single SiO 2 coupling in our design conditions. The onset voltage of the micro-discharge on the bias/guard ring has been studied for an extended electrode and a floating guard ring. (orig.)

  10. 30 CFR 57.12080 - Bare conductor guards.

    Science.gov (United States)

    2010-07-01

    ....12080 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity... conductors are less than 7 feet above the rail, they shall be guarded at all points where persons work or...

  11. The Rotating Ring-Ring Electrode. Theory and Experiment

    NARCIS (Netherlands)

    Kuiken, H.K.; Bakkers, E.P.A.M.; Ligthart, H.; Kelly, J.J.

    2000-01-01

    A model is presented for the rotating ring-ring electrode. Although the electrode is defined by four characteristic lengths, it is shown that the collection efficiency depends on only two dimensionless parameters. A simple relationship between these and the corresponding parameters for the rotating

  12. Comparison of water-use efficiency estimates based on tree-ring carbon isotopes with simulations of a dynamic vegetation model

    Science.gov (United States)

    Saurer, Matthias; Renato, Spahni; Fortunat, Joos; David, Frank; Kerstin, Treydte; Rolf, Siegwolf

    2015-04-01

    Tree-ring d13C-based estimates of intrinsic water-use efficiency (iWUE, reflecting the ratio of assimilation A to stomatal conductance gs) generally show a strong increase during the industrial period, likely associated with the increase in atmospheric CO2. However, it is not clear, first, if tree-ring d13C-derived iWUE-values indeed reflect actual plant and ecosystem-scale variability in fluxes and, second, what physiological changes were the drivers of the observed iWUE increase, changes in A or gs or both. To address these questions, we used a complex dynamic vegetation model (LPX) that combines process-based vegetation dynamics with land-atmosphere carbon and water exchange. The analysis was conducted for three functional types, representing conifers, oaks, larch, and various sites in Europe, where tree-ring isotope data are available. The increase in iWUE over the 20th century was comparable in LPX-simulations as in tree-ring-estimates, strengthening confidence in these results. Furthermore, the results from the LPX model suggest that the cause of the iWUE increase was reduced stomatal conductance during recent decades rather than increased assimilation. High-frequency variation reflects the influence of climate, like for example the 1976 summer drought, resulting in strongly reduced A and g in the model, particularly for oak.

  13. DOF-binding sites additively contribute to guard cell-specificity of AtMYB60 promoter

    Directory of Open Access Journals (Sweden)

    Cominelli Eleonora

    2011-11-01

    Full Text Available Abstract Background We previously demonstrated that the Arabidopsis thaliana AtMYB60 protein is an R2R3MYB transcription factor required for stomatal opening. AtMYB60 is specifically expressed in guard cells and down-regulated at the transcriptional levels by the phytohormone ABA. Results To investigate the molecular mechanisms governing AtMYB60 expression, its promoter was dissected through deletion and mutagenesis analyses. By studying different versions of AtMYB60 promoter::GUS reporter fusions in transgenic plants we were able to demonstrate a modular organization for the AtMYB60 promoter. Particularly we defined: a minimal promoter sufficient to confer guard cell-specific activity to the reporter gene; the distinct roles of different DOF-binding sites organised in a cluster in the minimal promoter in determining guard cell-specific expression; the promoter regions responsible for the enhancement of activity in guard cells; a promoter region responsible for the negative transcriptional regulation by ABA. Moreover from the analysis of single and multiple mutants we could rule out the involvement of a group of DOF proteins, known as CDFs, already characterised for their involvement in flowering time, in the regulation of AtMYB60 expression. Conclusions These findings shed light on the regulation of gene expression in guard cells and provide new promoter modules as useful tools for manipulating gene expression in guard cells, both for physiological studies and future biotechnological applications.

  14. Computational Modelling of Piston Ring Dynamics in 3D

    Directory of Open Access Journals (Sweden)

    Dlugoš Jozef

    2014-12-01

    Full Text Available Advanced computational models of a piston assembly based on the level of virtual prototypes require a detailed description of piston ring behaviour. Considering these requirements, the piston rings operate in regimes that cannot, in general, be simplified into an axisymmetric model. The piston and the cylinder liner do not have a perfect round shape, mainly due to machining tolerances and external thermo-mechanical loads. If the ring cannot follow the liner deformations, a local loss of contact occurs resulting in blow-by and increased consumption of lubricant oil in the engine. Current computational models are unable to implement such effects. The paper focuses on the development of a flexible 3D piston ring model based on the Timoshenko beam theory using the multibody system (MBS. The MBS model is compared to the finite element method (FEM solution.

  15. Piranti Lunak Pengujian Struktur Matematika Grup, Ring, Field Berbasis Osp (Open Source Program

    Directory of Open Access Journals (Sweden)

    Ngarap Im Manik

    2014-06-01

    Full Text Available This design of a computer software is a development and continuation of the software made on the previous research (2009/2010. However, this further research developed and expanded the scopes of testing more on the Siclic Group, Isomorphism Group, Semi Group, Sub Group and Abelian Group, Factor Ring, Sub Ring and Polynomial Ring; developed on the OSP (Open Source Program-based. The software was developed using the OSP-based language programming, such Java, so it is open and free to use for its users. This research succeeded to develop an open source software of Java program that can be used for testing specific mathematical Groups, such Ciclic Group, Isomorphism Group, Semi Group, Sub Group and Abelian Group, and Rings, Commutative Ring, Division Ring, Ideal Sub Ring, Ring Homomorphism, Ring Epimorphism and Fields. By the results, the software developed was able to test as same as the results from manual testing.

  16. Sperm competition in humans: mate guarding behavior negatively correlates with ejaculate quality.

    Science.gov (United States)

    Leivers, Samantha; Rhodes, Gillian; Simmons, Leigh W

    2014-01-01

    In species where females mate with multiple males, the sperm from these males must compete to fertilise available ova. Sexual selection from sperm competition is expected to favor opposing adaptations in males that function either in the avoidance of sperm competition (by guarding females from rival males) or in the engagement in sperm competition (by increased expenditure on the ejaculate). The extent to which males may adjust the relative use of these opposing tactics has been relatively neglected. Where males can successfully avoid sperm competition from rivals, one might expect a decrease in their expenditure on tactics for the engagement in sperm competition and vice versa. In this study, we examine the relationship between mate guarding and ejaculate quality using humans as an empirical model. We found that men who performed fewer mate guarding behaviors produced higher quality ejaculates, having a greater concentration of sperm, a higher percentage of motile sperm and sperm that swam faster and less erratically. These effects were found independent of lifestyle factors or factors related to male quality. Our findings suggest that male expenditure on mate guarding and on the ejaculate may represent alternative routes to paternity assurance in humans.

  17. Tunable THz wave absorption by graphene-assisted plasmonic metasurfaces based on metallic split ring resonators

    International Nuclear Information System (INIS)

    Ahmadivand, Arash; Sinha, Raju; Karabiyik, Mustafa; Vabbina, Phani Kiran; Gerislioglu, Burak; Kaya, Serkan; Pala, Nezih

    2017-01-01

    Graphene plasmonics has been introduced as a novel platform to design various nano- and microstructures to function in a wide range of spectrum from optical to THz frequencies. Herein, we propose a tunable plasmonic metamaterial in the THz regime by using metallic (silver) concentric microscale split ring resonator arrays on a multilayer metasurface composed of silica and silicon layers. We obtained an absorption percentage of 47.9% including two strong Fano resonant dips in THz regime for the purely plasmonic metamaterial without graphene layer. Considering the data of an atomic graphene sheet (with the thickness of ~0.35 nm) in both analytical and experimental regimes obtained by prior works, we employed a graphene layer under concentric split ring resonator arrays and above the multilayer metasurface to enhance the absorption ratio in THz bandwidth. Our numerical and analytical results proved that the presence of a thin graphene layer enhances the absorption coefficient of MM to 64.35%, at the highest peak in absorption profile that corresponds to the Fano dip position. We also have shown that changing the intrinsic characteristics of graphene sheet leads to shifts in the position of Fano dips and variations in the absorption efficiency. The maximum percentage of absorption (~67%) was obtained for graphene-based MM with graphene layer with dissipative loss factor of 1477 Ω. Employing the antisymmetric feature of the split ring resonators, the proposed graphene-based metamaterial with strong polarization dependency is highly sensitive to the polarization angle of the incident THz beam.

  18. Wear Analysis of Top Piston Ring to Reduce Top Ring Reversal Bore Wear

    Directory of Open Access Journals (Sweden)

    P. Ilanthirayan

    2017-12-01

    Full Text Available The piston rings are the most important part in engine which controls the lubricating oil consumption and blowby of the gases. The lubricating film of oil is provided to seal of gases towards crankcase and also to give smooth friction free translatory motion between rings and liner. Of the three rings present top ring is more crucial as it does the main work of restricting gases downwards the crankcase. Boundary lubrication is present at the Top dead centre (TDC and Bottom dead centre (BDC of the liner surface. In addition to this, top ring is exposed to high temperature gases which makes the oil present near the top ring to get evaporated and decreasing its viscosity, making metal-metal contact most of the time. Due to this at TDC, excess wear happens on the liner which is termed as Top ring reversal bore wear. The wear rate depends upon many parameters such as lubrication condition, viscosity index, contact type, normal forces acting on ring, geometry of ring face, surface roughness, material property. The present work explores the wear depth for different geometries of barrel ring using Finite Element model with the help of Archard wear law and the same is validated through experimentation. The study reveals that Asymmetric barrel rings have less contact pressure which in turn reduces the wear at Top dead centre.

  19. PREFACE: Special section on vortex rings Special section on vortex rings

    Science.gov (United States)

    Fukumoto, Yasuhide

    2009-10-01

    This special section of Fluid Dynamics Research includes five articles on vortex rings in both classical and quantum fluids. The leading scientists of the field describe the trends in and the state-of-the-art development of experiments, theories and numerical simulations of vortex rings. The year 2008 was the 150th anniversary of 'vortex motion' since Hermann von Helmholtz opened up this field. In 1858, Helmholtz published a paper in Crelle's Journal which put forward the concept of 'vorticity' and made the first analysis of vortex motion. Fluid mechanics before that was limited to irrotational motion. In the absence of vorticity, the motion of an incompressible homogeneous fluid is virtually equivalent to a rigid-body motion in the sense that the fluid motion is determined once the boundary configuration is specified. Helmholtz proved, among other things, that, without viscosity, a vortex line is frozen into the fluid. This Helmholtz's law immediately implies the preservation of knots and links of vortex lines and its implication is enormous. One of the major trends of fluid mechanics since the latter half of the 20th century is to clarify the topological meaning of Helmholtz's law and to exploit it to develop theoretical and numerical methods to find the solutions of the Euler equations and to develop experimental techniques to gain an insight into fluid motion. Vortex rings are prominent coherent structures in a variety of fluid motions from the microscopic scale, through human and mesoscale to astrophysical scales, and have attracted people's interest. The late professor Philip G Saffman (1981) emphasized the significance of studies on vortex rings. One particular motion exemplifies the whole range of problems of vortex motion and is also a commonly known phenomenon, namely the vortex ring or smoke ring. Vortex rings are easily produced by dropping drops of one liquid into another, or by puffing fluid out of a hole, or by exhaling smoke if one has the skill

  20. Aharonov-Casher effect and quantum transport in graphene based nano rings: A self-consistent Born approximation

    Science.gov (United States)

    Ghaderzadeh, A.; Rahbari, S. H. Ebrahimnazhad; Phirouznia, A.

    2018-03-01

    In this study, Rashba coupling induced Aharonov-Casher effect in a graphene based nano ring is investigated theoretically. The graphene based nano ring is considered as a central device connected to semi-infinite graphene nano ribbons. In the presence of the Rashba spin-orbit interaction, two armchair shaped edge nano ribbons are considered as semi-infinite leads. The non-equilibrium Green's function approach is utilized to obtain the quantum transport characteristics of the system. The relaxation and dephasing mechanisms within the self-consistent Born approximation is scrutinized. The Lopez-Sancho method is also applied to obtain the self-energy of the leads. We unveil that the non-equilibrium current of the system possesses measurable Aharonov-Casher oscillations with respect to the Rashba coupling strength. In addition, we have observed the same oscillations in dilute impurity regimes in which amplitude of the oscillations is shown to be suppressed as a result of the relaxations.

  1. Vortex rings

    CERN Document Server

    Akhmetov, D G

    2009-01-01

    This text on vortex rings covers their theoretical foundation, systematic investigations, and practical applications such as the extinction of fires at gushing oil wells. It pays special attention to the formation and motion of turbulent vortex rings.

  2. Ring Confidential Transactions

    Directory of Open Access Journals (Sweden)

    Shen Noether

    2016-12-01

    Full Text Available This article introduces a method of hiding transaction amounts in the strongly decentralized anonymous cryptocurrency Monero. Similar to Bitcoin, Monero is a cryptocurrency which is distributed through a proof-of-work “mining” process having no central party or trusted setup. The original Monero protocol was based on CryptoNote, which uses ring signatures and one-time keys to hide the destination and origin of transactions. Recently the technique of using a commitment scheme to hide the amount of a transaction has been discussed and implemented by Bitcoin Core developer Gregory Maxwell. In this article, a new type of ring signature, A Multilayered Linkable Spontaneous Anonymous Group signature is described which allows one to include a Pedersen Commitment in a ring signature. This construction results in a digital currency with hidden amounts, origins and destinations of transactions with reasonable efficiency and verifiable, trustless coin generation. The author would like to note that early drafts of this were publicized in the Monero Community and on the #bitcoin-wizards IRC channel. Blockchain hashed drafts are available showing that this work was started in Summer 2015, and completed in early October 2015. An eprint is also available at http://eprint.iacr.org/2015/1098.

  3. Time-zoning for the safe-guarding of capture fisheries: a closed season in Tamil Nadu, India

    NARCIS (Netherlands)

    Bavinck, M.; de Klerk, L.; van Dijk, D.; Rothuizen, J.V.; Blok, A.N.; Bokhorst, J.R.; van Haastrecht, E.K.; van de Loo, T.J.C.; Quaedvlieg, J.G.J.; Scholtens, J.

    2008-01-01

    A closed fishing season is arguably the most important fisheries regulation measure implemented by the government of India in the new millennium. Applied mainly to the inshore trawl fishing fleet, the planners’ intention was a safe-guarding of capture fisheries. This article, which is based on

  4. Elimination of Coast Guard plan review for non-critical engineering systems and cargo barges

    Science.gov (United States)

    1994-06-21

    The purpose of this Circular is to publish policy that provides for the elimination of Coast Guard review and approval of certain engineering system drawings for all vessels as well as structural drawings for Coast Guard inspected non-self propelled ...

  5. The Arabidopsis arc5 and arc6 mutations differentially affect plastid morphology in pavement and guard cells in the leaf epidermis.

    Science.gov (United States)

    Fujiwara, Makoto T; Yasuzawa, Mana; Kojo, Kei H; Niwa, Yasuo; Abe, Tomoko; Yoshida, Shigeo; Nakano, Takeshi; Itoh, Ryuuichi D

    2018-01-01

    Chloroplasts, or photosynthetic plastids, multiply by binary fission, forming a homogeneous population in plant cells. In Arabidopsis thaliana, the division apparatus (or division ring) of mesophyll chloroplasts includes an inner envelope transmembrane protein ARC6, a cytoplasmic dynamin-related protein ARC5 (DRP5B), and members of the FtsZ1 and FtsZ2 families of proteins, which co-assemble in the stromal mid-plastid division ring (FtsZ ring). FtsZ ring placement is controlled by several proteins, including a stromal factor MinE (AtMinE1). During leaf mesophyll development, ARC6 and AtMinE1 are necessary for FtsZ ring formation and thus plastid division initiation, while ARC5 is essential for a later stage of plastid division. Here, we examined plastid morphology in leaf epidermal pavement cells (PCs) and stomatal guard cells (GCs) in the arc5 and arc6 mutants using stroma-targeted fluorescent proteins. The arc5 PC plastids were generally a bit larger than those of the wild type, but most had normal shapes and were division-competent, unlike mutant mesophyll chloroplasts. The arc6 PC plastids were heterogeneous in size and shape, including the formation of giant and mini-plastids, plastids with highly developed stromules, and grape-like plastid clusters, which varied on a cell-by-cell basis. Moreover, unique plastid phenotypes for stomatal GCs were observed in both mutants. The arc5 GCs rarely lacked chlorophyll-bearing plastids (chloroplasts), while they accumulated minute chlorophyll-less plastids, whereas most GCs developed wild type-like chloroplasts. The arc6 GCs produced large chloroplasts and/or chlorophyll-less plastids, as previously observed, but unexpectedly, their chloroplasts/plastids exhibited marked morphological variations. We quantitatively analyzed plastid morphology and partitioning in paired GCs from wild-type, arc5, arc6, and atminE1 plants. Collectively, our results support the notion that ARC5 is dispensable in the process of equal division

  6. FUZZY RINGS AND ITS PROPERTIES

    Directory of Open Access Journals (Sweden)

    Karyati Karyati

    2017-01-01

      One of algebraic structure that involves a binary operation is a group that is defined  an un empty set (classical with an associative binary operation, it has identity elements and each element has an inverse. In the structure of the group known as the term subgroup, normal subgroup, subgroup and factor group homomorphism and its properties. Classical algebraic structure is developed to algebraic structure fuzzy by the researchers as an example semi group fuzzy and fuzzy group after fuzzy sets is introduced by L. A. Zadeh at 1965. It is inspired of writing about semi group fuzzy and group of fuzzy, a research on the algebraic structure of the ring is held with reviewing ring fuzzy, ideal ring fuzzy, homomorphism ring fuzzy and quotient ring fuzzy with its properties. The results of this study are obtained fuzzy properties of the ring, ring ideal properties fuzzy, properties of fuzzy ring homomorphism and properties of fuzzy quotient ring by utilizing a subset of a subset level  and strong level  as well as image and pre-image homomorphism fuzzy ring.   Keywords: fuzzy ring, subset level, homomorphism fuzzy ring, fuzzy quotient ring

  7. Double-blind evaluation of the DKL LifeGuard Model 2

    International Nuclear Information System (INIS)

    Murray, D.W.; Spencer, F.W.; Spencer, D.D.

    1998-05-01

    On March 20, 1998, Sandia National Laboratories performed a double-blind test of the DKL LifeGuard human presence detector and tracker. The test was designed to allow the device to search for individuals well within the product's published operational parameters. The Test Operator of the DKL LifeGuard was provided by the manufacturer and was a high-ranking member of DKL management. The test was developed and implemented to verify the performance of the device as specified by the manufacturer. The device failed to meet its published specifications and it performed no better than random chance

  8. Relational Reasoning for Markov Chains in a Probabilistic Guarded Lambda Calculus

    DEFF Research Database (Denmark)

    Aguirre, Alejandro; Barthe, Gilles; Birkedal, Lars

    2018-01-01

    We extend the simply-typed guarded $\\lambda$-calculus with discrete probabilities and endow it with a program logic for reasoning about relational properties of guarded probabilistic computations. This provides a framework for programming and reasoning about infinite stochastic processes like Mar...... literature to justify better proof rules for relational reasoning about probabilistic expressions. We illustrate these benefits with a broad range of examples that were beyond the scope of previous systems, including shift couplings and lump couplings between random walks....

  9. A design of a quasi-isochronous storage ring

    International Nuclear Information System (INIS)

    Lee, S.Y.; Trbojevic, D.

    1993-07-01

    Isochronous electron storage rings may offer advantages for future high luminosity meson factories. A Quasi-isochronous lattice based on the design principle of flexible γτ lattice is studied. The emittance and chromatic properties of such a lattice are studied. Applications of this design techniques for electron storage rings will be discussed

  10. Composite correlation filter for O-ring detection in stationary colored noise

    Science.gov (United States)

    Hassebrook, Laurence G.

    2009-04-01

    O-rings are regularly replaced in aircraft and if they are not replaced or if they are installed improperly, they can result in catastrophic failure of the aircraft. It is critical that the o-rings be packaged correctly to avoid mistakes made by technicians during routine maintenance. For this reason, fines may be imposed on the o-ring manufacturer if the o-rings are packaged incorrectly. That is, a single o-ring must be packaged and labeled properly. No o-rings or more than one o-ring per package is not acceptable. We present an industrial inspection system based on real-time composite correlation filtering that has successfully solved this problem in spite of opaque paper o-ring packages. We present the system design including the composite filter design.

  11. Physiologically-based pharmacokinetic model of vaginally administered dapivirine ring and film formulations.

    Science.gov (United States)

    Kay, Katherine; Shah, Dhaval K; Rohan, Lisa; Bies, Robert

    2018-05-01

    A physiologically-based pharmacokinetic (PBPK) model of the vaginal space was developed with the aim of predicting concentrations in the vaginal and cervical space. These predictions can be used to optimize the probability of success of vaginally administered dapivirine (DPV) for HIV prevention. We focus on vaginal delivery using either a ring or film. A PBPK model describing the physiological structure of the vaginal tissue and fluid was defined mathematically and implemented in MATLAB. Literature reviews provided estimates for relevant physiological and physiochemical parameters. Drug concentration-time profiles were simulated in luminal fluids, vaginal tissue and plasma after administration of ring or film. Patient data were extracted from published clinical trials and used to test model predictions. The DPV ring simulations tested the two dosing regimens and predicted PK profiles and area under the curve of luminal fluids (29 079 and 33 067 mg h l -1 in groups A and B, respectively) and plasma (0.177 and 0.211 mg h l -1 ) closely matched those reported (within one standard deviation). While the DPV film study reported drug concentration at only one time point per patient, our simulated profiles pass through reported concentration range. HIV is a major public health issue and vaginal microbicides have the potential to provide a crucial, female-controlled option for protection. The PBPK model successfully simulated realistic representations of drug PK. It provides a reliable, inexpensive and accessible platform where potential effectiveness of new compounds and the robustness of treatment modalities for pre-exposure prophylaxis can be evaluated. © 2018 The Authors. British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.

  12. Photonic crystal ring resonator-based four-channel dense wavelength division multiplexing demultiplexer on silicon on insulator platform: design and analysis

    Science.gov (United States)

    Sreenivasulu, Tupakula; Bhowmick, Kaustav; Samad, Shafeek A.; Yadunath, Thamerassery Illam R.; Badrinarayana, Tarimala; Hegde, Gopalkrishna; Srinivas, Talabattula

    2018-04-01

    A micro/nanofabrication feasible compact photonic crystal (PC) ring-resonator-based channel drop filter has been designed and analyzed for operation in C and L bands of communication window. The four-channel demultiplexer consists of ring resonators of holes in two-dimensional PC slab. The proposed assembly design of dense wavelength division multiplexing setup is shown to achieve optimal quality factor, without altering the lattice parameters or resonator size or inclusion of scattering holes. Transmission characteristics are analyzed using the three-dimensional finite-difference time-domain simulation approach. The radiation loss of the ring resonator was minimized by forced cancelation of radiation fields by fine-tuning the air holes inside the ring resonator. An average cross talk of -34 dB has been achieved between the adjacent channels maintaining an average quality factor of 5000. Demultiplexing is achieved by engineering only the air holes inside the ring, which makes it a simple and tolerant design from the fabrication perspective. Also, the device footprint of 500 μm2 on silicon on insulator platform makes it easy to fabricate the device using e-beam lithography technique.

  13. Polar lunar power ring: Propulsion energy resource

    Science.gov (United States)

    Galloway, Graham Scott

    1990-01-01

    A ring shaped grid of photovoltaic solar collectors encircling a lunar pole at 80 to 85 degrees latitude is proposed as the primary research, development, and construction goal for an initial lunar base. The polar Lunar Power Ring (LPR) is designed to provide continuous electrical power in ever increasing amounts as collectors are added to the ring grid. The LPR can provide electricity for any purpose indefinitely, barring a meteor strike. The associated rail infrastructure and inherently expandable power levels place the LPR as an ideal tool to power an innovative propulsion research facility or a trans-Jovian fleet. The proposed initial output range is 90 Mw to 90 Gw.

  14. A passive on-chip, superconducting circulator using rings of tunnel junctions

    OpenAIRE

    Müller, Clemens; Guan, Shengwei; Vogt, Nicolas; Cole, Jared H.; Stace, Thomas M.

    2017-01-01

    We present the design of a passive, on-chip microwave circulator based on a ring of superconducting tunnel junctions. We investigate two distinct physical realisations, based on either Josephson junctions (JJ) or quantum phase slip elements (QPS), with microwave ports coupled either capacitively (JJ) or inductively (QPS) to the ring structure. A constant bias applied to the center of the ring provides the symmetry breaking (effective) magnetic field, and no microwave or rf bias is required. W...

  15. Dual-Band Split-Ring Antenna Design for WLAN Applications

    OpenAIRE

    BAŞARAN, S. Cumhur; ERDEMLİ, Yunus E.

    2014-01-01

    A dual-band microstrip antenna based on split-ring elements is introduced for WLAN (2.4/5.2 GHz) applications. The proposed split-ring antenna (SRA) has a compact novel design which provides about 2% impedance-bandwidth without a need for additional matching network. Analysis and design of the proposed microstrip antenna is carried out by means of full-wave simulators based on the finite-element method.

  16. Linking heterometallic rings for quantum information processing and amusement.

    Science.gov (United States)

    Timco, Grigore A; Faust, Thomas B; Tuna, Floriana; Winpenny, Richard E P

    2011-06-01

    Linking polymetallic cages can be a method for creating new structures and new properties. In this tutorial review we use heterometallic anti-ferromagnetically coupled rings (AF-rings) as exemplars for three approaches that can be used to link cage compounds. The first of three routes involves an ion-pair interaction supported by hydrogen-bonding interactions, which allows the synthesis of hybrid rotaxanes among other materials. The second route involves functionalising the exterior of the AF-ring so that it will act as a Lewis base; complexes involving coordination of pyridine to bridging monometallic and dimetallic fragments are discussed. The third route involves creating a vacancy on one site of the AF-ring, and then using the ring as a Lewis acid. Di-imine ligands can then be used to link the AF-rings into dimers. A brief discussion of the physical properties of these systems is also included.

  17. 78 FR 77359 - Eighth Coast Guard District Annual Safety Zones; New Year's Eve Celebration/City of Mobile...

    Science.gov (United States)

    2013-12-23

    ...-AA00 Eighth Coast Guard District Annual Safety Zones; New Year's Eve Celebration/City of Mobile; Mobile Channel; Mobile, AL AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard will enforce the City of Mobile New Year's Eve Celebration safety zone in the Mobile Channel, Mobile, AL from...

  18. Design and implementation of optical switches based on nonlinear plasmonic ring resonators: Circular, square and octagon

    Science.gov (United States)

    Ghadrdan, Majid; Mansouri-Birjandi, Mohammad Ali

    2018-05-01

    In this paper, all-optical plasmonic switches (AOPS) based on various configurations of circular, square and octagon nonlinear plasmonic ring resonators (NPRR) were proposed and numerically investigated. Each of these configurations consisted of two metal-insulator-metal (MIM) waveguides coupled to each other by a ring resonator (RR). Nonlinear Kerr effect was used to show switching performance of the proposed NPRR. The result showed that the octagon switch structure had lower threshold power and higher transmission ratio than square and circular switch structures. The octagon switch structure had a low threshold power equal to 7.77 MW/cm2 and the high transmission ratio of approximately 0.6. Therefore, the octagon switch structure was an appropriate candidate to be applied in optical integration circuits as an AOPS.

  19. A new storage-ring light source

    Energy Technology Data Exchange (ETDEWEB)

    Chao, Alex [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-06-01

    A recently proposed technique in storage ring accelerators is applied to provide potential high-power sources of photon radiation. The technique is based on the steady-state microbunching (SSMB) mechanism. As examples of this application, one may consider a high-power DUV photon source for research in atomic and molecular physics or a high-power EUV radiation source for industrial lithography. A less challenging proof-of-principle test to produce IR radiation using an existing storage ring is also considered.

  20. Evaluation of ion collection area in Faraday probes.

    Science.gov (United States)

    Brown, Daniel L; Gallimore, Alec D

    2010-06-01

    A Faraday probe with three concentric rings was designed and fabricated to assess the effect of gap width and collector diameter in a systematic study of the diagnostic ion collection area. The nested Faraday probe consisted of two concentric collector rings and an outer guard ring, which enabled simultaneous current density measurements on the inner and outer collectors. Two versions of the outer collector were fabricated to create gaps of 0.5 and 1.5 mm between the rings. Distribution of current density in the plume of a low-power Hall thruster ion source was measured in azimuthal sweeps at constant radius from 8 to 20 thruster diameters downstream of the exit plane with variation in facility background pressure. A new analytical technique is proposed to account for ions collected in the gap between the Faraday probe collector and guard ring. This method is shown to exhibit excellent agreement between all nested Faraday probe configurations, and to reduce the magnitude of integrated ion beam current to levels consistent with Hall thruster performance analyses. The technique is further studied by varying the guard ring bias potential with a fixed collector bias potential, thereby controlling ion collection in the gap. Results are in agreement with predictions based on the proposed analytical technique. The method is applied to a past study comparing the measured ion current density profiles of two Faraday probe designs. These findings provide new insight into the nature of ion collection in Faraday probe diagnostics, and lead to improved accuracy with a significant reduction in measurement uncertainty.

  1. Evaluation of ion collection area in Faraday probes

    International Nuclear Information System (INIS)

    Brown, Daniel L.; Gallimore, Alec D.

    2010-01-01

    A Faraday probe with three concentric rings was designed and fabricated to assess the effect of gap width and collector diameter in a systematic study of the diagnostic ion collection area. The nested Faraday probe consisted of two concentric collector rings and an outer guard ring, which enabled simultaneous current density measurements on the inner and outer collectors. Two versions of the outer collector were fabricated to create gaps of 0.5 and 1.5 mm between the rings. Distribution of current density in the plume of a low-power Hall thruster ion source was measured in azimuthal sweeps at constant radius from 8 to 20 thruster diameters downstream of the exit plane with variation in facility background pressure. A new analytical technique is proposed to account for ions collected in the gap between the Faraday probe collector and guard ring. This method is shown to exhibit excellent agreement between all nested Faraday probe configurations, and to reduce the magnitude of integrated ion beam current to levels consistent with Hall thruster performance analyses. The technique is further studied by varying the guard ring bias potential with a fixed collector bias potential, thereby controlling ion collection in the gap. Results are in agreement with predictions based on the proposed analytical technique. The method is applied to a past study comparing the measured ion current density profiles of two Faraday probe designs. These findings provide new insight into the nature of ion collection in Faraday probe diagnostics, and lead to improved accuracy with a significant reduction in measurement uncertainty.

  2. Broadband pulsed difference frequency generation laser source centered 3326 nm based on ring fiber lasers

    Science.gov (United States)

    Chen, Guangwei; Li, Wenlei

    2018-03-01

    A broadband pulsed mid-infrared difference frequency generation (DFG) laser source based on MgO-doped congruent LiNbO3 bulk is experimentally demonstrated, which employs a homemade pulsed ytterbium-doped ring fiber laser and a continuous wave erbium-doped ring fiber laser to act as seed sources. The experimental results indicate that the perfect phase match crystal temperature is about 74.5∘C. The maximum spectrum bandwidth of idler is about 60 nm with suitable polarization states of fundamental lights. The central wavelength of idlers varies from 3293 nm to 3333 nm over the crystal temperature ranges of 70.4-76∘C. A jump of central wavelength exists around crystal temperature of 72∘C with variation of about 30 nm. The conversion efficiency of DFG can be tuned with the crystal temperature and polarization states of fundamental lights.

  3. Stirling engine piston ring

    Science.gov (United States)

    Howarth, Roy B.

    1983-01-01

    A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

  4. How does the blue-ringed octopus (Hapalochlaena lunulata) flash its blue rings?

    Science.gov (United States)

    Mäthger, Lydia M; Bell, George R R; Kuzirian, Alan M; Allen, Justine J; Hanlon, Roger T

    2012-11-01

    The blue-ringed octopus (Hapalochlaena lunulata), one of the world's most venomous animals, has long captivated and endangered a large audience: children playing at the beach, divers turning over rocks, and biologists researching neurotoxins. These small animals spend much of their time in hiding, showing effective camouflage patterns. When disturbed, the octopus will flash around 60 iridescent blue rings and, when strongly harassed, bite and deliver a neurotoxin that can kill a human. Here, we describe the flashing mechanism and optical properties of these rings. The rings contain physiologically inert multilayer reflectors, arranged to reflect blue-green light in a broad viewing direction. Dark pigmented chromatophores are found beneath and around each ring to enhance contrast. No chromatophores are above the ring; this is unusual for cephalopods, which typically use chromatophores to cover or spectrally modify iridescence. The fast flashes are achieved using muscles under direct neural control. The ring is hidden by contraction of muscles above the iridophores; relaxation of these muscles and contraction of muscles outside the ring expose the iridescence. This mechanism of producing iridescent signals has not previously been reported in cephalopods and we suggest that it is an exceptionally effective way to create a fast and conspicuous warning display.

  5. Single guard cell recordings in intact plants : light-induced hyperpolarization of the plasma membrane

    NARCIS (Netherlands)

    Roelfsema, MRG; Steinmeyer, R; Staal, M; Hedrich, R

    Guard cells are electrically isolated from other plant cells and therefore offer the unique possibility to conduct current- and voltage-clamp recordings on single cells in an intact plant. Guard cells in their natural environment were impaled with double-barreled electrodes and found to exhibit

  6. α-Skew π-McCoy Rings

    Directory of Open Access Journals (Sweden)

    Areej M. Abduldaim

    2013-01-01

    Full Text Available As a generalization of α-skew McCoy rings, we introduce the concept of α-skew π-McCoy rings, and we study the relationships with another two new generalizations, α-skew π1-McCoy rings and α-skew π2-McCoy rings, observing the relations with α-skew McCoy rings, π-McCoy rings, α-skew Armendariz rings, π-regular rings, and other kinds of rings. Also, we investigate conditions such that α-skew π1-McCoy rings imply α-skew π-McCoy rings and α-skew π2-McCoy rings. We show that in the case where R is a nonreduced ring, if R is 2-primal, then R is an α-skew π-McCoy ring. And, let R be a weak (α,δ-compatible ring; if R is an α-skew π1-McCoy ring, then R is α-skew π2-McCoy.

  7. Longevity of guard cell chloroplasts in falling leaves: implication for stomatal function and cellular aging.

    Science.gov (United States)

    Zeiger, E; Schwartz, A

    1982-11-12

    Guard cell chloroplasts in senescing leaves from 12 species of perennial trees and three species of annual plants survived considerably longer than their mesophyll counterparts. In Ginkgo biloba, stomata from yellow leaves opened during the day and closed at night; guard cell chloroplasts from these leaves showed fluorescence transients associated with electron transport and photophosphorylation. These findings indicate that guard cell chloroplasts are highly conserved throughout the life-span of the leaf and that leaves retain stomatal control during senescence.

  8. Space Weather Effects Produced by the Ring Current Particles

    Science.gov (United States)

    Ganushkina, Natalia; Jaynes, Allison; Liemohn, Michael

    2017-11-01

    One of the definitions of space weather describes it as the time-varying space environment that may be hazardous to technological systems in space and/or on the ground and/or endanger human health or life. The ring current has its contributions to space weather effects, both in terms of particles, ions and electrons, which constitute it, and magnetic and electric fields produced and modified by it at the ground and in space. We address the main aspects of the space weather effects from the ring current starting with brief review of ring current discovery and physical processes and the Dst-index and predictions of the ring current and storm occurrence based on it. Special attention is paid to the effects on satellites produced by the ring current electrons. The ring current is responsible for several processes in the other inner magnetosphere populations, such as the plasmasphere and radiation belts which is also described. Finally, we discuss the ring current influence on the ionosphere and the generation of geomagnetically induced currents (GIC).

  9. Human Factors in Coast Guard Computer Security - An Analysis of Current Awareness and Potential Techniques to Improve Security Program Viability

    National Research Council Canada - National Science Library

    Whalen, Timothy

    2001-01-01

    .... This thesis attempts to identify both the susceptibility of Coast Guard information systems to human factors-based security risks and possible means for increasing user awareness of those risks...

  10. Modeling and analysis on ring-type piezoelectric transformers.

    Science.gov (United States)

    Ho, Shine-Tzong

    2007-11-01

    This paper presents an electromechanical model for a ring-type piezoelectric transformer (PT). To establish this model, vibration characteristics of the piezoelectric ring with free boundary conditions are analyzed in advance. Based on the vibration analysis of the piezoelectric ring, the operating frequency and vibration mode of the PT are chosen. Then, electromechanical equations of motion for the PT are derived based on Hamilton's principle, which can be used to simulate the coupled electromechanical system for the transformer. Such as voltage stepup ratio, input impedance, output impedance, input power, output power, and efficiency are calculated by the equations. The optimal load resistance and the maximum efficiency for the PT will be presented in this paper. Experiments also were conducted to verify the theoretical analysis, and a good agreement was obtained.

  11. Attitudes and perceptions towards novel objective measures of ARV-based vaginal ring use: Results from a global stakeholder survey.

    Science.gov (United States)

    Stalter, Randy M; Tharaldson, Jenae; Owen, Derek H; Okumu, Eunice; Moench, Thomas; Mack, Natasha; Tolley, Elizabeth E; MacQueen, Kathleen M

    2017-01-01

    Results of recent microbicide and pre-exposure prophylaxis clinical trials have shown adherence to be a significant challenge with new HIV prevention technologies. As the vaginal ring containing dapivirine moves into two open label follow-on studies (HOPE/MTN-025 and DREAM) and other antiretroviral-based and multi-purpose prevention technology ring products advance through the development pipeline, there is a need for more accurate and reliable measures of adherence to microbicide ring products. We previously conducted a comprehensive landscape analysis to identify new technologies that could be applied to adherence measurement of vaginal rings containing antiretrovirals. To explore attitudes and perceptions towards the approaches that we identified, we conducted a survey of stakeholders with experience and expertise in microbicide and HIV prevention clinical trials. From May to July 2015 an electronic survey was distributed via email to 894 stakeholders; a total of 206 eligible individuals responded to at least one question and were included in the data analysis. Survey respondents were presented with various objective measures and asked about their perceived acceptability to trial participants, feasibility of implementation by study staff, usefulness for measuring adherence and ethical concerns. Methods that require no additional input from the participant and require no modifications to the existing ring product (i.e., measurement of residual drug or excipient, or a vaginal analyte that enters the ring) were viewed as being more acceptable to trial participants and more feasible to implement in the field. Respondents saw value in using objective measures to provide real-time feedback on adherence. However, approaches that involve unannounced home visits for sample collection or spot checks of ring use, which could provide significant value to adherence feedback efforts, were met with skepticism. Additional research on the acceptability of these methods to

  12. Attitudes and perceptions towards novel objective measures of ARV-based vaginal ring use: Results from a global stakeholder survey.

    Directory of Open Access Journals (Sweden)

    Randy M Stalter

    Full Text Available Results of recent microbicide and pre-exposure prophylaxis clinical trials have shown adherence to be a significant challenge with new HIV prevention technologies. As the vaginal ring containing dapivirine moves into two open label follow-on studies (HOPE/MTN-025 and DREAM and other antiretroviral-based and multi-purpose prevention technology ring products advance through the development pipeline, there is a need for more accurate and reliable measures of adherence to microbicide ring products. We previously conducted a comprehensive landscape analysis to identify new technologies that could be applied to adherence measurement of vaginal rings containing antiretrovirals. To explore attitudes and perceptions towards the approaches that we identified, we conducted a survey of stakeholders with experience and expertise in microbicide and HIV prevention clinical trials. From May to July 2015 an electronic survey was distributed via email to 894 stakeholders; a total of 206 eligible individuals responded to at least one question and were included in the data analysis. Survey respondents were presented with various objective measures and asked about their perceived acceptability to trial participants, feasibility of implementation by study staff, usefulness for measuring adherence and ethical concerns. Methods that require no additional input from the participant and require no modifications to the existing ring product (i.e., measurement of residual drug or excipient, or a vaginal analyte that enters the ring were viewed as being more acceptable to trial participants and more feasible to implement in the field. Respondents saw value in using objective measures to provide real-time feedback on adherence. However, approaches that involve unannounced home visits for sample collection or spot checks of ring use, which could provide significant value to adherence feedback efforts, were met with skepticism. Additional research on the acceptability of these

  13. Ring cavity surface emitting semiconductor lasers

    International Nuclear Information System (INIS)

    Mujagic, E.

    2010-01-01

    Quantum cascade lasers (QCLs) are electrically driven semiconductor lasers, which have undergone a steady improvement since the first demonstration in 1994. These are now well established as reliable sources of coherent light in the mid-infrared (MIR) and terahertz (THz)range of the electromagnetic spectrum (3-300 μm). The rapid progress of this type of lasers is based on a high degree of freedom in tailoring the emission wavelength within a large variety of semiconductor heterostructure designs and materials. These properties have attracted the attention of various applications such as gas analysis, chemical sensing, spectral imaging and free-space telecommunication. In order to improve the selectivity, sensitivity and efficiency of today's sensor systems, high optical power, continuous wave and room temperature performance, single-mode operation and low divergence optical beams, are highly desirable qualities of a compact laser source in this field of research. Since all of these features cannot be provided by a conventional edge-emitting device at the same time, research has put focus on the development of surface emitting devices. Nowadays, the vertical cavity surface emitting lasers (VCSELs) are the most prominent representative for this type of light emitters. With its capability of producing narrow circular beams, the feasibility of two-dimensional arrays and on-wafer testing, such a coherent light source results in a reduction of the fabrication effort and production costs. Since the radiation in QCLs is strictly polarized normal to the epitaxial layer plane, fabrication of VCSELs based on QC structures is not viable. The subject of this work is the design and realization of 'ring cavity surface emitting lasers' (ring-CSELs). This type of lasers employs a circular ring cavity and a resonant distributed feedback (DFB) surface grating. Ring-CSELs were fabricated on the basis of MIR and THz QC structures, which cover a wavelength range from 4 μm to 93

  14. Rings Research in the Next Decade

    Science.gov (United States)

    Burns, J. A.; Tiscareno, M. S.

    2009-12-01

    The study of planetary ring systems forms a key component of planetary science for several reasons: 1) The evolution and current states of planets and their satellites are affected in many ways by rings, while 2) conversely, properties of planets and moons and other solar system populations are revealed by their effects on rings; 3) highly structured and apparently delicate ring systems may be bellwethers, constraining various theories of the origin and evolution of their entire planetary system; and finally, 4) planetary rings provide an easily observable analogue to other astrophysical disk systems, enabling real “ground truth” results applicable to disks much more remote in space and/or time, including proto-planetary disks, circum-stellar disks, and even galaxies. Significant advances have been made in rings science in the past decade. The highest-priority rings research recommendations of the last Planetary Science Decadal Survey were to operate and extend the Cassini orbiter mission at Saturn; this has been done with tremendous success, accounting for much of the progress made on key science questions, as we will describe. Important progress in understanding the rings of Saturn and other planets has also come from Earth-based observational and theoretical work, again as prioritized by the last Decadal Survey. However, much important work remains to be done. At Saturn, the Cassini Solstice Mission must be brought to a successful completion. Priority should also be placed on sending spacecraft to Neptune and/or Uranus, now unvisited for more than 20 years. At Jupiter and Pluto, opportunities afforded by visiting spacecraft capable of studying rings should be exploited. On Earth, the need for continued research and analysis remains strong, including in-depth analysis of rings data already obtained, numerical and theoretical modeling work, laboratory analysis of materials and processes analogous to those found in the outer solar system, and continued Earth-based

  15. Ring-Opening Polymerization of N-Carboxyanhydrides for Preparation of Polypeptides and Polypeptide-Based Hybrid Materials with Various Molecular Architectures

    KAUST Repository

    Pahovnik, David; Hadjichristidis, Nikolaos

    2015-01-01

    Different synthetic approaches utilizing ring-opening polymerization of N-carboxyanhydrides for preparation of polypeptide and polypeptide-based hybrid materials with various molecular architectures are described. An overview of polymerization

  16. VUV optical ring resonator for Duke storage ring free electron laser

    Energy Technology Data Exchange (ETDEWEB)

    Park, S.H.; Litvinenko, V.N.; Madey, J.M.J. [Duke Univ., Durham, NC (United States)] [and others

    1995-12-31

    The conceptual design of the multifaceted-mirror ring resonator for Duke storage ring VUV FEL is presented. The expected performance of the OK-4 FEL with ring resonator is described. We discuss in this paper our plans to study reflectivity of VUV mirrors and their resistivity to soft X-ray spontaneous radiation from OK-4 undulator.

  17. Guard Cell Signal Transduction Network: Advances in Understanding Abscisic Acid, CO2, and Ca2+ Signaling

    KAUST Repository

    Kim, Tae-Houn

    2010-05-04

    Stomatal pores are formed by pairs of specialized epidermal guard cells and serve as major gateways for both CO2 influx into plants from the atmosphere and transpirational water loss of plants. Because they regulate stomatal pore apertures via integration of both endogenous hormonal stimuli and environmental signals, guard cells have been highly developed as a model system to dissect the dynamics and mechanisms of plant-cell signaling. The stress hormone ABA and elevated levels of CO2 activate complex signaling pathways in guard cells that are mediated by kinases/phosphatases, secondary messengers, and ion channel regulation. Recent research in guard cells has led to a new hypothesis for how plants achieve specificity in intracellular calcium signaling: CO2 and ABA enhance (prime) the calcium sensitivity of downstream calcium-signaling mechanisms. Recent progress in identification of early stomatal signaling components are reviewed here, including ABA receptors and CO2-binding response proteins, as well as systems approaches that advance our understanding of guard cell-signaling mechanisms.

  18. Guard Cell Signal Transduction Network: Advances in Understanding Abscisic Acid, CO2, and Ca2+ Signaling

    KAUST Repository

    Kim, Tae-Houn; Bö hmer, Maik; Hu, Honghong; Nishimura, Noriyuki; Schroeder, Julian I.

    2010-01-01

    Stomatal pores are formed by pairs of specialized epidermal guard cells and serve as major gateways for both CO2 influx into plants from the atmosphere and transpirational water loss of plants. Because they regulate stomatal pore apertures via integration of both endogenous hormonal stimuli and environmental signals, guard cells have been highly developed as a model system to dissect the dynamics and mechanisms of plant-cell signaling. The stress hormone ABA and elevated levels of CO2 activate complex signaling pathways in guard cells that are mediated by kinases/phosphatases, secondary messengers, and ion channel regulation. Recent research in guard cells has led to a new hypothesis for how plants achieve specificity in intracellular calcium signaling: CO2 and ABA enhance (prime) the calcium sensitivity of downstream calcium-signaling mechanisms. Recent progress in identification of early stomatal signaling components are reviewed here, including ABA receptors and CO2-binding response proteins, as well as systems approaches that advance our understanding of guard cell-signaling mechanisms.

  19. Actin filaments regulate the adhesion between the plasma membrane and the cell wall of tobacco guard cells.

    Science.gov (United States)

    Yu, Qin; Ren, Jing-Jing; Kong, Lan-Jing; Wang, Xiu-Ling

    2018-01-01

    During the opening and closing of stomata, guard cells undergo rapid and reversible changes in their volume and shape, which affects the adhesion of the plasma membrane (PM) to the cell wall (CW). The dynamics of actin filaments in guard cells are involved in stomatal movement by regulating structural changes and intracellular signaling. However, it is unclear whether actin dynamics regulate the adhesion of the PM to the CW. In this study, we investigated the relationship between actin dynamics and PM-CW adhesion by the hyperosmotic-induced plasmolysis of tobacco guard cells. We found that actin filaments in guard cells were depolymerized during mannitol-induced plasmolysis. The inhibition of actin dynamics by treatment with latrunculin B or jasplakinolide and the disruption of the adhesion between the PM and the CW by treatment with RGDS peptide (Arg-Gly-Asp-Ser) enhanced guard cell plasmolysis. However, treatment with latrunculin B alleviated the RGDS peptide-induced plasmolysis and endocytosis. Our results reveal that the actin depolymerization is involved in the regulation of the PW-CW adhesion during hyperosmotic-induced plasmolysis in tobacco guard cells.

  20. Interaction Region Design for a Ring-Ring LHeC

    CERN Document Server

    Thompson, L N S; Bernard, N R; Fitterer, M; Holzer, B; Klein, M; Kostka, P

    2011-01-01

    tively low energy and moderately high intensity provides high luminosity TeV-scale e-p collisions at one of the LHC interaction points, running simultaneously with existing experiments. Two designs are studied; an electron ring situated in the LHC tunnel, and an electron linac. The focus of this paper is on the ring design. Designing an e-p machine presents interesting accelerator physics and design challenges, particularly when considering the interaction region. These include coupled optics, beam separation and unconventional mini-beta focusing schemes. Designs are constrained by an array of interdependent factors, including beam-beam interaction, detector dimensions and acceptance, luminosity and synchrotron radiation. Methods of addressing these complex issues are discussed. The current designs for the LHeC Ring-Ring interaction region and long straight section are presented and discussed, in the context of the project goals and design challenges encountered. Future developments and work are also discusse...

  1. Redesign of the Advanced Education processes in the United States Coast Guard

    OpenAIRE

    Johnson, Lamar V.; Sanders, Marc F.

    1999-01-01

    The processes used in the operation of the Coast Guard Advanced Education Program have evolved as most business processes that were developed prior to the introduction of information technology. These processes include the selection, management, assignment and tracking of advanced education students. These processes are still fully dependent on physical files and the mail system. The Coast Guard has an information technology infrastructure that supports better processes, however it is not bei...

  2. A Reconfigurable Mesh-Ring Topology for Bluetooth Sensor Networks

    Directory of Open Access Journals (Sweden)

    Ben-Yi Wang

    2018-05-01

    Full Text Available In this paper, a Reconfigurable Mesh-Ring (RMR algorithm is proposed for Bluetooth sensor networks. The algorithm is designed in three stages to determine the optimal configuration of the mesh-ring network. Firstly, a designated root advertises and discovers its neighboring nodes. Secondly, a scatternet criterion is built to compute the minimum number of piconets and distributes the connection information for piconet and scatternet. Finally, a peak-search method is designed to determine the optimal mesh-ring configuration for various sizes of networks. To maximize the network capacity, the research problem is formulated by determining the best connectivity of available mesh links. During the formation and maintenance phases, three possible configurations (including piconet, scatternet, and hybrid are examined to determine the optimal placement of mesh links. The peak-search method is a systematic approach, and is implemented by three functional blocks: the topology formation block generates the mesh-ring topology, the routing efficiency block computes the routing performance, and the optimum decision block introduces a decision-making criterion to determine the optimum number of mesh links. Simulation results demonstrate that the optimal mesh-ring configuration can be determined and that the scatternet case achieves better overall performance than the other two configurations. The RMR topology also outperforms the conventional ring-based and cluster-based mesh methods in terms of throughput performance for Bluetooth configurable networks.

  3. Functional Analysis of Cellulose and Xyloglucan in the Walls of Stomatal Guard Cells of Arabidopsis1[OPEN

    Science.gov (United States)

    Rui, Yue; Anderson, Charles T.

    2016-01-01

    Stomatal guard cells are pairs of specialized epidermal cells that control water and CO2 exchange between the plant and the environment. To fulfill the functions of stomatal opening and closure that are driven by changes in turgor pressure, guard cell walls must be both strong and flexible, but how the structure and dynamics of guard cell walls enable stomatal function remains poorly understood. To address this question, we applied cell biological and genetic analyses to investigate guard cell walls and their relationship to stomatal function in Arabidopsis (Arabidopsis thaliana). Using live-cell spinning disk confocal microscopy, we measured the motility of cellulose synthase (CESA)-containing complexes labeled by green fluorescent protein (GFP)-CESA3 and observed a reduced proportion of GFP-CESA3 particles colocalizing with microtubules upon stomatal closure. Imaging cellulose organization in guard cells revealed a relatively uniform distribution of cellulose in the open state and a more fibrillar pattern in the closed state, indicating that cellulose microfibrils undergo dynamic reorganization during stomatal movements. In cesa3je5 mutants defective in cellulose synthesis and xxt1 xxt2 mutants lacking the hemicellulose xyloglucan, stomatal apertures, changes in guard cell length, and cellulose reorganization were aberrant during fusicoccin-induced stomatal opening or abscisic acid-induced stomatal closure, indicating that sufficient cellulose and xyloglucan are required for normal guard cell dynamics. Together, these results provide new insights into how guard cell walls allow stomata to function as responsive mediators of gas exchange at the plant surface. PMID:26729799

  4. Advertisement call and tadpole morphology of the clutch-guarding ...

    African Journals Online (AJOL)

    Advertisement call and tadpole morphology of the clutch-guarding frog Mantidactylus argenteus from eastern ... We provide the first descriptions of the tadpole and advertisement call of Mantidactylus argenteus. ... AJOL African Journals Online.

  5. Photonic crystal ring resonator based optical filters for photonic integrated circuits

    International Nuclear Information System (INIS)

    Robinson, S.

    2014-01-01

    In this paper, a two Dimensional (2D) Photonic Crystal Ring Resonator (PCRR) based optical Filters namely Add Drop Filter, Bandpass Filter, and Bandstop Filter are designed for Photonic Integrated Circuits (PICs). The normalized output response of the filters is obtained using 2D Finite Difference Time Domain (FDTD) method and the band diagram of periodic and non-periodic structure is attained by Plane Wave Expansion (PWE) method. The size of the device is minimized from a scale of few tens of millimeters to the order of micrometers. The overall size of the filters is around 11.4 μm × 11.4 μm which is highly suitable of photonic integrated circuits

  6. Probabilistic Role Models and the Guarded Fragment

    DEFF Research Database (Denmark)

    Jaeger, Manfred

    2004-01-01

    We propose a uniform semantic framework for interpreting probabilistic concept subsumption and probabilistic role quantification through statistical sampling distributions. This general semantic principle serves as the foundation for the development of a probabilistic version of the guarded fragm...... fragment of first-order logic. A characterization of equivalence in that logic in terms of bisimulations is given....

  7. Probabilistic role models and the guarded fragment

    DEFF Research Database (Denmark)

    Jaeger, Manfred

    2006-01-01

    We propose a uniform semantic framework for interpreting probabilistic concept subsumption and probabilistic role quantification through statistical sampling distributions. This general semantic principle serves as the foundation for the development of a probabilistic version of the guarded fragm...... fragment of first-order logic. A characterization of equivalence in that logic in terms of bisimulations is given....

  8. Personal Staff - Joint Staff - The National Guard

    Science.gov (United States)

    the ARNG Deputy Director of the ARNG Chief of Staff of the ARNG Command Chief Warrant Officer of the Site Maintenance Battle Focused Training Strategy Battle Staff Training Resources News Publications March Today in Guard History Leadership CNGB VCNGB SEA DANG DARNG Joint Staff J-1 J-2 J-3 J-4 J-5 J-6 J

  9. Almagest, a new trackless ring finding algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Lamanna, G., E-mail: gianluca.lamanna@cern.ch

    2014-12-01

    A fast ring finding algorithm is a crucial point to allow the use of RICH in on-line trigger selection. The present algorithms are either too slow (with respect to the incoming data rate) or need the information coming from a tracking system. Digital image techniques, assuming limited computing power (as for example Hough transform), are not perfectly robust for what concerns the noise immunity. We present a novel technique based on Ptolemy's theorem for multi-ring pattern recognition. Starting from purely geometrical considerations, this algorithm (also known as “Almagest”) allows fast and trackless rings reconstruction, with spatial resolution comparable with other offline techniques. Almagest is particularly suitable for parallel implementation on multi-cores machines. Preliminary tests on GPUs (multi-cores video card processors) show that, thanks to an execution time smaller than 10 μs per event, this algorithm could be employed for on-line selection in trigger systems. The user case of the NA62 RICH trigger, based on GPU, will be discussed. - Highlights: • A new algorithm for fast multiple ring searching in RICH detectors is presented. • The Almagest algorithm exploits the computing power of Graphics processers (GPUs). • A preliminary implementation for on-line triggering in the NA62 experiment shows encouraging results.

  10. Hybrid plasmonic waveguide-assisted Metal–Insulator–Metal ring resonator for refractive index sensing

    Science.gov (United States)

    Butt, M. A.; Khonina, S. N.; Kazanskiy, N. L.

    2018-05-01

    A highly sensitive refractive index sensor based on an integrated hybrid plasmonic waveguide (HPWG) and a Metal-Insulator-Metal (M-I-M) micro-ring resonator is presented. In our design, there are two slot-waveguide-based micro-rings that encircle a gold disc. The outer slot WG is formed by the combination of Silicon-Air-Gold ring and the inner slot-waveguide is formed by Gold ring-Air-Gold disc. The slot-waveguide rings provide an interaction length sufficient to accumulate a detectable wavelength shift. The transmission spectrum and electric field distribution of this sensor structure are simulated using Finite Element Method (FEM). The sensitivity of this micro-ring resonator is achieved at 800 nm/RIU which is about six times higher than that of the conventional Si ring with the same geometry. Our proposed sensor design has a potential to find further applications in biomedical science and nano-photonic circuits.

  11. Design studies for the electron storage ring EUTERPE

    Energy Technology Data Exchange (ETDEWEB)

    Boling, Xi

    1995-05-18

    The 400 MeV electron storage ring EUTERPE is under construction at Eindhoven University of Technology. The ring is to be used as an experimental tool for accelerator physics studies and synchroton radiation applications. The main task of the current research work is the electron optical design of the ring. Lattice design is a basis for machine design as a whole. Design aspects regarding the basic lattice, based on single particle dynamics, include determination of the equilibrium beam size and bunch length, design of achromatic bending sections, selection of tune values, correction of chromaticity, and minimization of the natural emittance in the ring. The basic lattice designed for the EUTERPE ring has a high flexibility so that different electron optical modes can be realized easily. In low energy storage rings with a high beam current, collective effects can cause a significant change in the bunch length, the transverse emittance and the beam lifetime. In order to ensure a good optical performance for the ring, the choice of suitable parameters concerning the vacuum and RF system are essential as far as collective effects are concerned. An estimation of the collective effects in the ring is given. The injector for EUTERPE is a 75 MeV racetrack microtron which is injected from a 10 MeV linac. In order to get sufficient beam current in the ring, a special procedure of continuous injection with an adjustable locally shifted closed orbit has been presented. Details of the injection procedure and numerical simulations are given. (orig./HSI).

  12. Design studies for the electron storage ring EUTERPE

    International Nuclear Information System (INIS)

    Xi Boling.

    1995-01-01

    The 400 MeV electron storage ring EUTERPE is under construction at Eindhoven University of Technology. The ring is to be used as an experimental tool for accelerator physics studies and synchroton radiation applications. The main task of the current research work is the electron optical design of the ring. Lattice design is a basis for machine design as a whole. Design aspects regarding the basic lattice, based on single particle dynamics, include determination of the equilibrium beam size and bunch length, design of achromatic bending sections, selection of tune values, correction of chromaticity, and minimization of the natural emittance in the ring. The basic lattice designed for the EUTERPE ring has a high flexibility so that different electron optical modes can be realized easily. In low energy storage rings with a high beam current, collective effects can cause a significant change in the bunch length, the transverse emittance and the beam lifetime. In order to ensure a good optical performance for the ring, the choice of suitable parameters concerning the vacuum and RF system are essential as far as collective effects are concerned. An estimation of the collective effects in the ring is given. The injector for EUTERPE is a 75 MeV racetrack microtron which is injected from a 10 MeV linac. In order to get sufficient beam current in the ring, a special procedure of continuous injection with an adjustable locally shifted closed orbit has been presented. Details of the injection procedure and numerical simulations are given. (orig./HSI)

  13. Uniquely Strongly Clean Group Rings

    Institute of Scientific and Technical Information of China (English)

    WANG XIU-LAN

    2012-01-01

    A ring R is called clean if every element is the sum of an idempotent and a unit,and R is called uniquely strongly clean (USC for short) if every element is uniquely the sum of an idempotent and a unit that commute.In this article,some conditions on a ring R and a group G such that RG is clean are given.It is also shown that if G is a locally finite group,then the group ring RG is USC if and only if R is USC,and G is a 2-group.The left uniquely exchange group ring,as a middle ring of the uniquely clean ring and the USC ring,does not possess this property,and so does the uniquely exchange group ring.

  14. Multiband Split-Ring Resonator Based Planar Inverted-F Antenna for 5G Applications

    Directory of Open Access Journals (Sweden)

    Muhammad Kamran Ishfaq

    2017-01-01

    Full Text Available 5G, the fifth generation of wireless communications, is focusing on multiple frequency bands, such as 6 GHz, 10 GHz, 15 GHz, 28 GHz, and 38 GHz, to achieve high data rates up to 10 Gbps or more. The industry demands multiband antennas to cover these distant frequency bands, which is a task much more challenging. In this paper, we have designed a novel multiband split-ring resonator (SRR based planar inverted-F antenna (PIFA for 5G applications. It is composed of a PIFA, an inverted-L parasitic element, a rectangular shaped parasitic element, and a split-ring resonator (SRR etched on the top plate of the PIFA. The basic PIFA structure resonates at 6 GHz. An addition of a rectangular shaped parasitic element produces a resonance at 15 GHz. The introduction of a split-ring resonator produces a band notch at 8 GHz, and a resonance at 10 GHz, while the insertion of an inverted-L shaped parasitic element further enhances the impedance bandwidth in the 10 GHz band. The frequency bands covered, each with more than 1 GHz impedance bandwidth, are 6 GHz (5–7 GHz, 10 GHz (9–10.8 GHz, and 15 GHz (14-15 GHz, expected for inclusion in next-generation wireless communications, that is, 5G. The design is simulated using Ansys Electromagnetic Suite 17 simulation software package. The simulated and the measured results are compared and analyzed which are generally in good agreement.

  15. Influence of ring growth rate on damage development in hot ring rolling

    NARCIS (Netherlands)

    Wang, C.; Geijselaers, H. J.M.; Omerspahic, E.; Recina, V.; van den Boogaard, A. H.

    2015-01-01

    As an incremental forming process of bulk metal, ring rolling provides a cost effective process route to manufacture seamless rings. In the production of hot rolled rings, defects such as porosity can sometimes be found in high alloyed steel, manufactured from ingots having macro-segregation. For

  16. Numerical studies on a plasmonic temperature nanosensor based on a metal-insulator-metal ring resonator structure for optical integrated circuit applications

    Science.gov (United States)

    Al-mahmod, Md. Jubayer; Hyder, Rakib; Islam, Md Zahurul

    2017-07-01

    A nanosensor, based on a metal-insulator-metal (MIM) plasmonic ring resonator, is proposed for potential on-chip temperature sensing and its performance is evaluated numerically. The sensor components can be fabricated by using planar processes on a silicon substrate, making its manufacturing compatible to planar electronic fabrication technology. The sensor, constructed using silver as the metal rings and a thermo-optic liquid ethanol film between the metal layers, is capable of sensing temperature with outstanding optical sensitivity, as high as -0.53 nm/°C. The resonance wavelength is found to be highly sensitive to the refractive index of the liquid dielectric film. The resonance peak can be tuned according to the requirement of intended application by changing the radii of the ring resonator geometries in the design phase. The compact size, planar and silicon-based design, and very high resolutions- these characteristics are expected to make this sensor technology a preferred choice for lab-on-a-chip applications, as compared to other contemporary sensors.

  17. Dynamic apeerture in damping rings with realistic wigglers

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yunhai; /SLAC

    2005-05-04

    The International Linear Collider based on superconducting RF cavities requires the damping rings to have extremely small equilibrium emittance, huge circumference, fast damping time, and large acceptance. To achieve all of these requirements is a very challenging task. In this paper, we will present a systematic approach to designing the damping rings using simple cells and non-interlaced sextupoles. The designs of the damping rings with various circumferences and shapes, including dogbone, are presented. To model realistic wigglers, we have developed a new hybrid symplectic integrator for faster and accurate evaluation of dynamic aperture of the lattices.

  18. Ring rotational speed trend analysis by FEM approach in a Ring Rolling process

    Science.gov (United States)

    Allegri, G.; Giorleo, L.; Ceretti, E.

    2018-05-01

    Ring Rolling is an advanced local incremental forming technology to fabricate directly precise seamless ring-shape parts with various dimensions and materials. In this process two different deformations occur in order to reduce the width and the height of a preform hollow ring; as results a diameter expansion is obtained. In order to guarantee a uniform deformation, the preform is forced toward the Driver Roll whose aim is to transmit the rotation to the ring. The ring rotational speed selection is fundamental because the higher is the speed the higher will be the axial symmetry of the deformation process. However, it is important to underline that the rotational speed will affect not only the final ring geometry but also the loads and energy needed to produce it. Despite this importance in industrial environment, usually, a constant value for the Driver Roll angular velocity is set so to result in a decreasing trend law for the ring rotational speed. The main risk due to this approach is not fulfilling the axial symmetric constrain (due to the diameter expansion) and to generate a high localized ring section deformation. In order to improve the knowledge about this topic in the present paper three different ring rotational speed trends (constant, linearly increasing and linearly decreasing) were investigated by FEM approach. Results were compared in terms of geometrical and dimensional analysis, loads and energies required.

  19. Mechanical improvement of metal reinforcement rings for a finite ring-shaped superconducting bulk

    Science.gov (United States)

    Huang, Chen-Guang; Zhou, You-He

    2018-03-01

    As a key technique, reinforcement of type-II superconducting bulks with metal rings can efficiently improve their mechanical properties to enhance the maximum trapped field. In this paper, we study the magnetostrictive and fracture behaviors of a finite superconducting ring bulk reinforced by three typical reinforcing structures composed of metal rings during the magnetizing process by means of the minimization of magnetic energy and the finite element method. After a field-dependent critical current density is adopted, the magnetostriction, pinning-induced stress, and crack tip stress intensity factor are calculated considering the demagnetization effects. The results show that the mechanical properties of the ring bulk are strongly dependent on the reinforcing structure and the material and geometrical parameters of the metal rings. Introducing the metal ring can significantly reduce the hoop stress, and the reduction effect by internal reinforcement is much improved relative to external reinforcement. By comparison, bilateral reinforcement seems to be the best candidate structure. Only when the metal rings have particular Young's modulus and radial thickness will they contribute to improve the mechanical properties the most. In addition, if an edge crack is pre-existing in the ring bulk, the presence of metal rings can effectively avoid crack propagation since it reduces the crack tip stress intensity factor by nearly one order of magnitude.

  20. Effect of nonlinear electrostatic forces on the dynamic behaviour of a capacitive ring-based Coriolis Vibrating Gyroscope under severe shock

    Science.gov (United States)

    Chouvion, B.; McWilliam, S.; Popov, A. A.

    2018-06-01

    This paper investigates the dynamic behaviour of capacitive ring-based Coriolis Vibrating Gyroscopes (CVGs) under severe shock conditions. A general analytical model is developed for a multi-supported ring resonator by describing the in-plane ring response as a finite sum of modes of a perfect ring and the electrostatic force as a Taylor series expansion. It is shown that the supports can induce mode coupling and that mode coupling occurs when the shock is severe and the electrostatic forces are nonlinear. The influence of electrostatic nonlinearity is investigated by numerically simulating the governing equations of motion. For the severe shock cases investigated, when the electrode gap reduces by ∼ 60 % , it is found that three ring modes of vibration (1 θ, 2 θ and 3 θ) and a 9th order force expansion are needed to obtain converged results for the global shock behaviour. Numerical results when the 2 θ mode is driven at resonance indicate that electrostatic nonlinearity introduces mode coupling which has potential to reduce sensor performance under operating conditions. Under some circumstances it is also found that severe shocks can cause the vibrating response to jump to another stable state with much lower vibration amplitude. This behaviour is mainly a function of shock amplitude and rigid-body motion damping.

  1. Fault diagnosis for wind turbine planetary ring gear via a meshing resonance based filtering algorithm.

    Science.gov (United States)

    Wang, Tianyang; Chu, Fulei; Han, Qinkai

    2017-03-01

    Identifying the differences between the spectra or envelope spectra of a faulty signal and a healthy baseline signal is an efficient planetary gearbox local fault detection strategy. However, causes other than local faults can also generate the characteristic frequency of a ring gear fault; this may further affect the detection of a local fault. To address this issue, a new filtering algorithm based on the meshing resonance phenomenon is proposed. In detail, the raw signal is first decomposed into different frequency bands and levels. Then, a new meshing index and an MRgram are constructed to determine which bands belong to the meshing resonance frequency band. Furthermore, an optimal filter band is selected from this MRgram. Finally, the ring gear fault can be detected according to the envelope spectrum of the band-pass filtering result. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  2. Report of the New Rings Study Group

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, S.D.; Dugan, G.; Marriner, J.

    1987-10-19

    We have taken the approach here of trying to understand both the feasibility and practicality of varied options for new rings at Fermilab, rather than trying to produce a single detailed design. In other words, this document is not a design report and should not be construed as such. Our perception of the potential needs for new rings (in order of priority) is as follows: Antiproton Storage and/or Recovery: A facility for storing up to 4 x 10/sup 12/ antiprotons is needed. Recovery of antiprotons from the collider becomes a viable option if the luminosity is indeed dominated by emittance dilution rather than beam loss. New or Post-Booster: The goal here would be to inject into the existing Main Ring above transition. Improved performance of the Main Ring would be anticipated. New Main Ring: Advantages would include better emittance preservation, a faster cycle time for antiproton production, and the removal of interference/backgrounds at the B0 and D0 detectors. We discuss in this paper various scenarios based on one or more combinations of the above possibilities. 14 figs., 10 tabs.

  3. Report of the New Rings Study Group

    International Nuclear Information System (INIS)

    Holmes, S.D.; Dugan, G.; Marriner, J.

    1987-01-01

    We have taken the approach here of trying to understand both the feasibility and practicality of varied options for new rings at Fermilab, rather than trying to produce a single detailed design. In other words, this document is not a design report and should not be construed as such. Our perception of the potential needs for new rings (in order of priority) is as follows: Antiproton Storage and/or Recovery: A facility for storing up to 4 x 10 12 antiprotons is needed. Recovery of antiprotons from the collider becomes a viable option if the luminosity is indeed dominated by emittance dilution rather than beam loss. New or Post-Booster: The goal here would be to inject into the existing Main Ring above transition. Improved performance of the Main Ring would be anticipated. New Main Ring: Advantages would include better emittance preservation, a faster cycle time for antiproton production, and the removal of interference/backgrounds at the B0 and D0 detectors. We discuss in this paper various scenarios based on one or more combinations of the above possibilities. 14 figs., 10 tabs

  4. Ring correlations in random networks.

    Science.gov (United States)

    Sadjadi, Mahdi; Thorpe, M F

    2016-12-01

    We examine the correlations between rings in random network glasses in two dimensions as a function of their separation. Initially, we use the topological separation (measured by the number of intervening rings), but this leads to pseudo-long-range correlations due to a lack of topological charge neutrality in the shells surrounding a central ring. This effect is associated with the noncircular nature of the shells. It is, therefore, necessary to use the geometrical distance between ring centers. Hence we find a generalization of the Aboav-Weaire law out to larger distances, with the correlations between rings decaying away when two rings are more than about three rings apart.

  5. Novel ring resonator-based integrated photonic beamformer for broadband phased array receive antennas - part 2: experimental prototype

    NARCIS (Netherlands)

    Zhuang, L.; Roeloffzen, C.G.H.; Meijerink, Arjan; Burla, M.; Marpaung, D.A.I.; Leinse, Arne; Hoekman, M.; Heideman, Rene; van Etten, Wim

    2010-01-01

    An experimental prototype is presented that illustrates the implementation aspects and feasibility of the novel ring resonator-based optical beamformer concept that has been developed and analyzed in Part I of this paper . This concept can be used for seamless control of the reception angle in

  6. 78 FR 33216 - Temporary Change of Dates for Recurring Marine Event in the Fifth Coast Guard District, Mattaponi...

    Science.gov (United States)

    2013-06-04

    ... 1625-AA08 Temporary Change of Dates for Recurring Marine Event in the Fifth Coast Guard District, Mattaponi Drag Boat Race, Mattaponi River; Wakema, VA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary change to the enforcement period of special local...

  7. 76 FR 30827 - Temporary Change of Dates for Recurring Marine Event in the Fifth Coast Guard District; Elizabeth...

    Science.gov (United States)

    2011-05-27

    ...-AA08 Temporary Change of Dates for Recurring Marine Event in the Fifth Coast Guard District; Elizabeth River, Norfolk, VA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard will... various river boat races and a parade during the ``35th Annual Norfolk Harborfest Celebration.'' Special...

  8. Coherent x-rays and vacuum-ultraviolet radiation from storage-ring-based undulators and free electron lasers

    International Nuclear Information System (INIS)

    Kim, K.J.

    1984-12-01

    High-brightness electron storage rings and permanent-magnet technology provide a basis for the development of coherent radiation in the 10- to 1000-A (xuv) spectral range. The most assured route to the production of coherent x-rays and vuv is the simple interaction between properly constrained relativistic electrons and permanent-magnet undulators, a subject that is already well understood and where technology is well advanced. Other techniques are less well developed, but with increasing degrees of technical challenge they will provide additional coherence properties. Transverse optical klystrons (TOKs) provide an opportunity for additional coherence at certain harmonics of longer-wavelength lasers. Free electron lasers (FELs) extend coherence capabilities substantially through two possible routes: one is the development of suitable mirror coatings. Both FEL techniques would provide vuv radiation and soft x rays with extremely narrow spectral content. Research on all of these techniques (undulators, TOKs, and FELs) is possible in a single facility based on a high-brightness electron storage ring, referred to herein as a Coherent xuv Facility (CXF). Individual items from the report were prepared separately for the data base

  9. Assessment of private security guards by Suicide Probability Scale and Brief Symptom Inventory.

    Science.gov (United States)

    Dogan, Bulent; Canturk, Gurol; Canturk, Nergis; Guney, Sevgi; Özcan, Ebru

    2016-01-01

    The aim of the present study was to investigate the influence of suicide probability and relevant sociodemographic features and to provide information for preventing suicide in private security guards working under the stressful conditions and continuous exposure to the negative and traumatic life events. 200 private security guards and 200 personnels of Ankara University participated in the study. A sociodemographic information questionnaire, the Suicide Probability Scale (SPS) and the Brief Symptom Inventory (BSI) were used to collect the data. Gender, marital status, income, religious beliefs, experiencing a life-threatening situation, history of a suicide attempt, smoking and not having a chronic disease caused statistically significant differences in the scores for SPS between the private security guards group and the controls. Moreover there was a statistically significant positive correlation between the total scores of the subscales of SPS and the total scores of BSI. Like police officers and gendarmes, private security guards are at high risk of committing and attempting suicide because of being at stressful work settings and also suffering from secondary trauma. It is required that they should be aware of their tendency to commit suicide and have regular psychiatric screenings.

  10. The National Guard Ballistic Missile Defense Mission minutemen at the Orgital Plane

    OpenAIRE

    Trenary, Ralph Hiram

    2004-01-01

    Approved for public release; distribution is unlimited This thesis examines the decision to assign the Ballistic Missile Defense mission to units of the Colorado and Alaska National Guard. The history of the Nike Ajax, Nike Hercules, Sentinel and Safeguard programs are examined to identify the origins of support for this decision. First-hand sources provide evidence that the National Guard performance in the Nike air defense program is a record of parity and some superiority to equivalent ...

  11. Alpha - Skew Pi - Armendariz Rings

    Directory of Open Access Journals (Sweden)

    Areej M Abduldaim

    2018-03-01

    Full Text Available In this article we introduce a new concept called Alpha-skew Pi-Armendariz rings (Alpha - S Pi - ARas a generalization of the notion of Alpha-skew Armendariz rings.Another important goal behind studying this class of rings is to employ it in order to design a modern algorithm of an identification scheme according to the evolution of using modern algebra in the applications of the field of cryptography.We investigate general properties of this concept and give examples for illustration. Furthermore, this paperstudy the relationship between this concept and some previous notions related to Alpha-skew Armendariz rings. It clearly presents that every weak Alpha-skew Armendariz ring is Alpha-skew Pi-Armendariz (Alpha-S Pi-AR. Also, thisarticle showsthat the concepts of Alpha-skew Armendariz rings and Alpha-skew Pi- Armendariz rings are equivalent in case R is 2-primal and semiprime ring.Moreover, this paper proves for a semicommutative Alpha-compatible ringR that if R[x;Alpha] is nil-Armendariz, thenR is an Alpha-S Pi-AR. In addition, if R is an Alpha - S Pi -AR, 2-primal and semiprime ring, then N(R[x;Alpha]=N(R[x;Alpha]. Finally, we look forwardthat Alpha-skew Pi-Armendariz rings (Alpha-S Pi-ARbe more effect (due to their properties in the field of cryptography than Pi-Armendariz rings, weak Armendariz rings and others.For these properties and characterizations of the introduced concept Alpha-S Pi-AR, we aspire to design a novel algorithm of an identification scheme.

  12. Diagnostic double guarded low-volume uterine lavage in mares

    DEFF Research Database (Denmark)

    Christoffersen, Mette; Brandis, Louise; Samuelsson, Julia

    2014-01-01

    Endometritis constitutes a major problem in the management of broodmares; hence diagnostic tests with a high sensitivity and specificity are desired. We hypothesize that a double guarded uterine flush technique for bacterial culture and cytology is comparable to standard diagnostic tests, the end......Endometritis constitutes a major problem in the management of broodmares; hence diagnostic tests with a high sensitivity and specificity are desired. We hypothesize that a double guarded uterine flush technique for bacterial culture and cytology is comparable to standard diagnostic tests...... (lavage: 11%, swab: 8%, biopsy: 7%) (positive bacterial growth > 4 Colony forming units (CFU)). Positive cytology was less likely to occur when E. coli was isolated from the diagnostic tests compared to the growth of β-hemolytic streptococci. Isolation of pathogens from uterine samples was highly...

  13. RingSys-Scheduler User`s manual. Information terminal for town monitoring; Brukermanual for RingSys-Scheduler. Informasjonsterminal for byovervaaking

    Energy Technology Data Exchange (ETDEWEB)

    Marsteen, L.

    1996-02-01

    This report is a User`s manual. It describes RingSys Scheduler, a computer system for continuous display of time series, public information and static pictures. The computer is connected to a host machine via modem and time series, and public information are automatically updated once an hour. RingSys-Scheduler is PC based. It is developed using Excel`s macro language as well as the asynchronous communication program Dynacomm`s script language. 12 figs.

  14. From process to proxy: Ecological challenges and opportunities of tree-ring based environmental reconstructions

    Science.gov (United States)

    Wilmking, Martin; Buras, Allan; Heinrich, Ingo; Scharnweber, Tobias; Simard, Sonia; Smiljanic, Marko; van der Maaten, Ernst; van der Maaten-Theunissen, Marieke

    2014-05-01

    Trees are sessile, long-living organisms and as such constantly need to adapt to changing environmental conditions. Accordingly, they often show high phenotypic plasticity (the ability to change phenotypic traits, such as allocation of resources) in response to environmental change. This high phenotypic plasticity is generally considered as one of the main ingredients for a sessile organism to survive and reach high ages. Precisely because of the ability of trees to reach old age and their in-ability to simply run away when conditions get worse, growth information recorded in tree rings has long been used as a major environmental proxy, covering time scales from decades to millennia. Past environmental conditions (e.g. climate) are recorded in i.e. annual tree-ring width, early- and latewood width, wood density, isotopic concentrations, cell anatomy or wood chemistry. One prerequisite for a reconstruction is that the relationship between the environmental variable influencing tree growth and the tree-growth variable itself is stable through time. This, however, might contrast the ecological theory of high plasticity and the trees ability to adapt to change. To untangle possible mechanisms leading to stable or unstable relationships between tree growth and environmental variables, it is helpful to have exact site information and several proxy variables of each tree-ring series available. Although we gain insight into the environmental history of a sampling site when sampling today, this is extremely difficult when using archeological wood. In this latter case, we face the additional challenge of unknown origin, provenance and (or) site conditions, making it even more important to use multiple proxy time-series from the same sample. Here, we review typical examples, where the relationship between tree growth and environmental variables seems 1) stable and 2) instable through time, and relate these two cases to ecological theory. Based on ecological theory, we then

  15. Coloured leg bands affect male mate-guarding behaviour in the bluethroat

    Science.gov (United States)

    Johnsen; Lifjeld; Rohde

    1997-07-01

    Artificial traits such as coloured leg bands may affect an individual's mating success, as shown for some birds. One explanation is that colour-matching with a sexual ornament affects the individual's sexual attractiveness. This study reports a colour-band experiment with free-living bluethroats, Luscinia s. svecicaa species where males have a distinct blue and chestnut throat and upper breast. There was no apparent difference in pairing success between males with ornament-matching colour bands (blue and orange) and males with non-ornamental colour bands. However, males with ornamental bands guarded their mates less intensely and spent more time singing, performing song flights and intruding into neighbours' territories than males with non-ornamental bands. We conclude that colour bands affect the trade-off between mate guarding and advertisement behaviour in a way that is consistent with the hypothesis that bands with ornamental colours improve a male's attractiveness. The results are in concordance with a previous study of the same population, showing that males with experimentally reduced attractiveness guarded their mates more closely and advertised less for additional mates, than non-manipulated males.

  16. Tunable plasmonic filter with circular metal–insulator– metal ring ...

    Indian Academy of Sciences (India)

    The mechanism based on circular ring resonators with narrow gaps may provide a novel method for designing all-optical integrated components in optical communication and computing. Keywords. Metal–insulator–metal waveguide; surface plasmon; optical filters; ring resonator. PACS Nos 42.79.−e; 73.20.Mf; 78.20.Bh. 1.

  17. Ethernet ring protection with managed FDB using APS payload

    Science.gov (United States)

    Im, Jinsung; Ryoo, Jeong-dong; Joo, Bheom Soon; Rhee, J.-K. Kevin

    2007-11-01

    Ethernet ring protection (ERP) is a new technology based on OAM (operations, administration, and maintenance) being standardized by the ITU-T G.8032 working group. In this paper, we present the recent development of Ethernet ring protection which is called FDB (filtering database) flush scheme and propose a new Ethernet ring protection technique introducing a managed FDB using APS to deliver information how to fix FDB selectively. We discuss the current development of the ERP technology at ITU-T and performance comparisons between different proposals.

  18. Development of a Bunched Beam Electron Cooler based on ERL and Circulator Ring Technology for the Jefferson Lab Electron-Ion Collider

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Stephen V. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Derbenev, Yaroslav S. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Douglas, David R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Hannon, Fay E. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Hutton, Andrew M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Li, Rui [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Rimmer, Robert A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Roblin, Yves R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Tennant, Christopher D. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Wang, Haipeng [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Zhang, He [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Zhang, Yuhong [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2018-01-01

    Jefferson Lab is in the process of designing an electron ion collider with unprecedented luminosity at a 45 GeV center-of-mass energy. This luminosity relies on ion cooling in both the booster and the storage ring of the accelerator complex. The cooling in the booster will use a conventional DC cooler similar to the one at COSY. The high-energy storage ring, operating at a momentum of up to 100 GeV/nucleon, requires novel use of bunched-beam cooling. There are two designs for such a cooler. The first uses a conventional Energy Recovery Linac (ERL) with a magnetized beam while the second uses a circulating ring to enhance both peak and average currents experienced by the ion beam. This presentation will describe the design of both the Circulator Cooling Ring (CCR) design and that of the backup option using the stand-alone ERL operated at lower charge but higher repetition rate than the ERL injector required by the CCR-based design.

  19. Fusion Rings for Quantum Groups

    DEFF Research Database (Denmark)

    Andersen, Henning Haahr; Stroppel, Catharina

    2014-01-01

    We study the fusion rings of tilting modules for a quantum group at a root of unity modulo the tensor ideal of negligible tilting modules. We identify them in type A with the combinatorial rings from Korff, C., Stroppel, C.: The sl(ˆn)k-WZNW fusion ring: a combinato-rial construction...... and a realisation as quotient of quantum cohomology. Adv. Math. 225(1), 200–268, (2010) and give a similar description of the sp2n-fusion ring in terms of non-commutative symmetric functions. Moreover we give a presentation of all fusion rings in classical types as quotients of polynomial rings. Finally we also...... compute the fusion rings for type G2....

  20. The LSU Electron Storage Ring, the first commercially-built storage ring

    International Nuclear Information System (INIS)

    Sah, R.

    1990-01-01

    The Brobeck Division of Maxwell Laboratories, Inc., is building the first industrially-produced storage ring. It will be located at Louisiana State University (LSU) at the Center for Advanced Microstructures and Devices (CAMD) in Baton Rouge. The purpose of this electron storage ring is to provide intense beams of x-rays to advance the state-of-the-art in lithography and to permit research in a broad area. This facility consists of a 1.2 GeV, 400 mA electron storage ring with a 200 MeV linac injector. The magnet lattice is a Chasman-Green design (double-bend achromat), and the ring circumference is 55.2 meters. There are four 3.0 meter, dispersion-free straight sections, one for injection, one for the 500 MHz RF cavity, and two for possible future insertion devices. The storge ring construction project is in the detailed-design stage, and many systems are in the initial stages of fabrication. 4 figs., 1 tab

  1. Fusion rings and fusion ideals

    DEFF Research Database (Denmark)

    Andersen, Troels Bak

    by the so-called fusion ideals. The fusion rings of Wess-Zumino-Witten models have been widely studied and are well understood in terms of precise combinatorial descriptions and explicit generating sets of the fusion ideals. They also appear in another, more general, setting via tilting modules for quantum......This dissertation investigates fusion rings, which are Grothendieck groups of rigid, monoidal, semisimple, abelian categories. Special interest is in rational fusion rings, i.e., fusion rings which admit a finite basis, for as commutative rings they may be presented as quotients of polynomial rings...

  2. Analysis of reforming process of large distorted ring in final enlarging forging

    International Nuclear Information System (INIS)

    Miyazawa, Takeshi; Murai, Etsuo

    2002-01-01

    In the construction of reactors or pressure vessels for oil chemical plants and nuclear power stations, mono block open-die forging rings are often utilized. Generally, a large forged ring is manufactured by means of enlarging forging with reductions of the wall thickness. During the enlarging process the circular ring is often distorted and becomes an ellipse in shape. However the shape control of the ring is a complicated work. This phenomenon makes the matter still worse in forging of larger rings. In order to make precision forging of large rings, we have developed the forging method using a v-shape anvil. The v-shape anvil is geometrically adjusted to fit the distorted ring in the final circle and reform automatically the shape of the ring during enlarging forging. This paper has analyzed the reforming process of distorted ring by computer program based on F.E.M. and examined the effect on the precision of ring forging. (author)

  3. Antibodies to the CFTR modulate the turgor pressure of guard cell protoplasts via slow anion channels.

    Science.gov (United States)

    Leonhardt, N; Bazin, I; Richaud, P; Marin, E; Vavasseur, A; Forestier, C

    2001-04-06

    The plasma membrane guard cell slow anion channel is a key element at the basis of water loss control in plants allowing prolonged osmolite efflux necessary for stomatal closure. This channel has been extensively studied by electrophysiological approaches but its molecular identification is still lacking. Recently, we described that this channel was sharing some similarities with the mammalian ATP-binding cassette protein, cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel [Leonhardt, N. et al. (1999) Plant Cell 11, 1141-1151]. Here, using the patch-clamp technique and a bioassay, consisting in the observation of the change in guard cell protoplasts volume, we demonstrated that a functional antibody raised against the mammalian CFTR prevented ABA-induced guard cell protoplasts shrinking and partially inhibited the slow anion current. Moreover, this antibody immunoprecipitated a polypeptide from guard cell protein extracts and immunolabeled stomata in Vicia faba leaf sections. These results indicate that the guard cell slow anion channel is, or is closely controlled by a polypeptide, exhibiting one epitope shared with the mammalian CFTR.

  4. Multi-species consumer jams and the fall of guarded corals to crown-of-thorns seastar outbreaks

    Science.gov (United States)

    Kayal, Mohsen; Ballard, Jane; Adjeroud, Mehdi

    2018-01-01

    Outbreaks of predatory crown-of-thorns seastars (COTS) can devastate coral reef ecosystems, yet some corals possess mutualistic guardian crabs that defend against COTS attacks. However, guarded corals do not always survive COTS outbreaks, with the ecological mechanisms sealing the fate of these corals during COTS infestations remaining unknown. In August 2008 in Moorea (17.539° S, 149.830° W), French Polynesia, an unusually dense multi-species aggregation of predators was observed feeding upon guarded corals following widespread coral decline due to COTS predation. Concurrent assaults from these amplified, mixed-species predator guilds likely overwhelm mutualistic crab defense, ultimately leading to the fall of guarded corals. Our observations indicate that guarded corals can sustain devastating COTS attacks for an extended duration, but eventually concede to intensifying assaults from diverse predators that aggregate in high numbers as alternative prey decays. The fall of guarded corals is therefore suggested to be ultimately driven by an indirect trophic cascade that leads to amplified attacks from diverse starving predators following prey decline, rather than COTS assaults alone. PMID:29487739

  5. Simulations of a single vortex ring using an unbounded, regularized particle-mesh based vortex method

    DEFF Research Database (Denmark)

    Hejlesen, Mads Mølholm; Spietz, Henrik J.; Walther, Jens Honore

    2014-01-01

    , unbounded particle-mesh based vortex method is used to simulate the instability, transition to turbulence and eventual destruction of a single vortex ring. From the simulation data a novel method on analyzing the dynamics of the enstrophy is presented based on the alignment of the vorticity vector...... with the principal axis of the strain rate tensor. We find that the dynamics of the enstrophy density is dominated by the local flow deformation and axis of rotation, which is used to infer some concrete tendencies related to the topology of the vorticity field....

  6. 78 FR 40000 - Eighth Coast Guard District Annual Safety Zones; Riverfront Independence Festival Fireworks; Ohio...

    Science.gov (United States)

    2013-07-03

    ...-AA00 Eighth Coast Guard District Annual Safety Zones; Riverfront Independence Festival Fireworks; Ohio.... SUMMARY: The Coast Guard will enforce a Safety Zone for the Riverfront Independence Festival Fireworks on... navigable waters during the Riverfront Independence Festival Fireworks. During the enforcement period, in...

  7. Resting state networks' corticotopy: the dual intertwined rings architecture.

    Directory of Open Access Journals (Sweden)

    Salma Mesmoudi

    Full Text Available How does the brain integrate multiple sources of information to support normal sensorimotor and cognitive functions? To investigate this question we present an overall brain architecture (called "the dual intertwined rings architecture" that relates the functional specialization of cortical networks to their spatial distribution over the cerebral cortex (or "corticotopy". Recent results suggest that the resting state networks (RSNs are organized into two large families: 1 a sensorimotor family that includes visual, somatic, and auditory areas and 2 a large association family that comprises parietal, temporal, and frontal regions and also includes the default mode network. We used two large databases of resting state fMRI data, from which we extracted 32 robust RSNs. We estimated: (1 the RSN functional roles by using a projection of the results on task based networks (TBNs as referenced in large databases of fMRI activation studies; and (2 relationship of the RSNs with the Brodmann Areas. In both classifications, the 32 RSNs are organized into a remarkable architecture of two intertwined rings per hemisphere and so four rings linked by homotopic connections. The first ring forms a continuous ensemble and includes visual, somatic, and auditory cortices, with interspersed bimodal cortices (auditory-visual, visual-somatic and auditory-somatic, abbreviated as VSA ring. The second ring integrates distant parietal, temporal and frontal regions (PTF ring through a network of association fiber tracts which closes the ring anatomically and ensures a functional continuity within the ring. The PTF ring relates association cortices specialized in attention, language and working memory, to the networks involved in motivation and biological regulation and rhythms. This "dual intertwined architecture" suggests a dual integrative process: the VSA ring performs fast real-time multimodal integration of sensorimotor information whereas the PTF ring performs multi

  8. Resting State Networks' Corticotopy: The Dual Intertwined Rings Architecture

    Science.gov (United States)

    Mesmoudi, Salma; Perlbarg, Vincent; Rudrauf, David; Messe, Arnaud; Pinsard, Basile; Hasboun, Dominique; Cioli, Claudia; Marrelec, Guillaume; Toro, Roberto; Benali, Habib; Burnod, Yves

    2013-01-01

    How does the brain integrate multiple sources of information to support normal sensorimotor and cognitive functions? To investigate this question we present an overall brain architecture (called “the dual intertwined rings architecture”) that relates the functional specialization of cortical networks to their spatial distribution over the cerebral cortex (or “corticotopy”). Recent results suggest that the resting state networks (RSNs) are organized into two large families: 1) a sensorimotor family that includes visual, somatic, and auditory areas and 2) a large association family that comprises parietal, temporal, and frontal regions and also includes the default mode network. We used two large databases of resting state fMRI data, from which we extracted 32 robust RSNs. We estimated: (1) the RSN functional roles by using a projection of the results on task based networks (TBNs) as referenced in large databases of fMRI activation studies; and (2) relationship of the RSNs with the Brodmann Areas. In both classifications, the 32 RSNs are organized into a remarkable architecture of two intertwined rings per hemisphere and so four rings linked by homotopic connections. The first ring forms a continuous ensemble and includes visual, somatic, and auditory cortices, with interspersed bimodal cortices (auditory-visual, visual-somatic and auditory-somatic, abbreviated as VSA ring). The second ring integrates distant parietal, temporal and frontal regions (PTF ring) through a network of association fiber tracts which closes the ring anatomically and ensures a functional continuity within the ring. The PTF ring relates association cortices specialized in attention, language and working memory, to the networks involved in motivation and biological regulation and rhythms. This “dual intertwined architecture” suggests a dual integrative process: the VSA ring performs fast real-time multimodal integration of sensorimotor information whereas the PTF ring performs multi

  9. Major benefits of guarding behavior in subsocial bees: implications for social evolution

    OpenAIRE

    Mik?t, Michael; ?ern?, Kate?ina; Straka, Jakub

    2016-01-01

    Abstract Parental care is a behavior that increases the growth and survival of offspring, often at a cost to the parents' own survival and/or future reproduction. In this study, we focused on nest guarding, which is one of the most important types of extended parental care; we studied this behavior in two solitary bee species of the genus Ceratina with social ancestors. We performed the experiment of removing the laying female, who usually guards the nest after completing its provisioning, to...

  10. Refining types using type guards in TypeScript

    NARCIS (Netherlands)

    de Wolff, Ivo Gabe; Hage, J.

    2017-01-01

    We discuss two adaptations of the implementation of type guards and narrowing in the TypeScript compiler. The first is an improvement on the original syntax-directed implementation, and has now replaced the original one in the TypeScript compiler. It is specifically suited for the scenario in which

  11. EPA Region 1 Coast Guard Jurisdictional Boundary - Polygons

    Science.gov (United States)

    Jurisdictional boundary between EPA and Coast Guard for EPA Region I. Created from 1:100000 USGS DLGs with greater detail drawn from 1:24000 commercial street data for Region I.This layer is used to determine which agency will be reponsible in the event of an oil spill.

  12. EPA Region 1 Coast Guard Jurisdictional Boundary - Arcs

    Science.gov (United States)

    Jurisdictional boundary between EPA and Coast Guard for EPA Region I. Created from 1:100000 USGS DLGs with greater detail drawn from 1:24000 commercial street data for Region I.This layer is used to determine which agency will be reponsible in the event of an oil spill.

  13. Rice Stomatal Closure Requires Guard Cell Plasma Membrane ATP-Binding Cassette Transporter RCN1/OsABCG5.

    Science.gov (United States)

    Matsuda, Shuichi; Takano, Sho; Sato, Moeko; Furukawa, Kaoru; Nagasawa, Hidetaka; Yoshikawa, Shoko; Kasuga, Jun; Tokuji, Yoshihiko; Yazaki, Kazufumi; Nakazono, Mikio; Takamure, Itsuro; Kato, Kiyoaki

    2016-03-07

    Water stress is one of the major environmental stresses that affect agricultural production worldwide. Water loss from plants occurs primarily through stomatal pores. Here, we report that an Oryza sativa half-size ATP-binding cassette (ABC) subfamily G protein, RCN1/OsABCG5, is involved in stomatal closure mediated by phytohormone abscisic acid (ABA) accumulation in guard cells. We found that the GFP-RCN1/OsABCG5-fusion protein was localized at the plasma membrane in guard cells. The percentage of guard cell pairs containing both ABA and GFP-RCN1/OsABCG5 increased after exogenous ABA treatment, whereas they were co-localized in guard cell pairs regardless of whether exogenous ABA was applied. ABA application resulted in a smaller increase in the percentage of guard cell pairs containing ABA in rcn1 mutant (A684P) and RCN1-RNAi than in wild-type plants. Furthermore, polyethylene glycol (drought stress)-inducible ABA accumulation in guard cells did not occur in rcn1 mutants. Stomata closure mediated by exogenous ABA application was strongly reduced in rcn1 mutants. Finally, rcn1 mutant plants had more rapid water loss from detached leaves than the wild-type plants. These results indicate that in response to drought stress, RCN1/OsABCG5 is involved in accumulation of ABA in guard cells, which is indispensable for stomatal closure. Copyright © 2016 The Author. Published by Elsevier Inc. All rights reserved.

  14. Evaluation of ring impedance of the Photon Factory storage ring

    International Nuclear Information System (INIS)

    Kiuchi, T.; Izawa, M.; Tokumoto, S.; Hori, Y.; Sakanaka, S.; Kobayashi, M.; Kobayakawa, H.

    1992-05-01

    The loss parameters of the ducts in the Photon Factory (PF) storage ring were evaluated using the wire method and the code TBCI. Both the measurement and the calculation were done for a different bunch length (σ) ranging from 23 to 80 ps. The PF ring impedance was estimated to be |Z/n|=3.2 Ω using the broadband impedance model. The major contribution to the impedance comes from the bellows and the gate valve sections. Improvements of these components will lower the ring impedance by half. (author)

  15. Polarization Studies for the eRHIC Electron Storage Ring

    Energy Technology Data Exchange (ETDEWEB)

    Gianfelice-Wendt, Eliana [Fermilab; Tepikian, S. [Brookhaven

    2018-04-01

    A hadron/lepton collider with polarized beams has been under consideration by the scientific community since some years, in the U.S. and Europe. Among the various proposals, those by JLAB and BNL with polarized electron and proton beams are currently under closer study in the U.S. Experimenters call for the simultaneous storage of electron bunches with both spin helicity. In the BNL based Ring-Ring design, electrons are stored at top energy in a ring to be accommodated in the existing RHIC tunnel. The transversely polarized electron beam is injected into the storage ring at variable energies, between 5 and 18 GeV. Polarization is brought into the longitudinal direction at the IP by a couple of spin rotators. In this paper results of first studies of the attainable beam polarization level and lifetime in the storage ring at 18 GeV are presented.

  16. Development of dapivirine vaginal ring for HIV prevention.

    Science.gov (United States)

    Devlin, Bríd; Nuttall, Jeremy; Wilder, Susan; Woodsong, Cynthia; Rosenberg, Zeda

    2013-12-01

    In the continuing effort to develop effective HIV prevention methods for women, a vaginal ring containing the non-nucleoside reverse transcriptase inhibitor dapivirine is currently being tested in two safety and efficacy trials. This paper reviews dapivirine ring's pipeline development process, including efforts to determine safe and effective dosing levels as well as identify delivery platforms with the greatest likelihood of success for correct and consistent use. Dapivirine gel and other formulations were developed and tested in preclinical and clinical studies. Multiple vaginal ring prototypes were also tested, resulting in the current ring design as well as additional designs under consideration for future testing. Efficacy results from clinical trials are expected in 2015. Through ongoing consultations with national regulatory authorities, licensure requirements for dapivirine vaginal ring approval have been defined. This article is based on a presentation at the "Product Development Workshop 2013: HIV and Multipurpose Prevention Technologies," held in Arlington, Virginia on February 21-22, 2013. It forms part of a special supplement to Antiviral Research. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Tree Rings: Timekeepers of the Past.

    Science.gov (United States)

    Phipps, R. L.; McGowan, J.

    One of a series of general interest publications on science issues, this booklet describes the uses of tree rings in historical and biological recordkeeping. Separate sections cover the following topics: dating of tree rings, dating with tree rings, tree ring formation, tree ring identification, sample collections, tree ring cross dating, tree…

  18. UWB Bandpass Filter with Ultra-wide Stopband based on Ring Resonator

    Science.gov (United States)

    Kazemi, Maryam; Lotfi, Saeedeh; Siahkamari, Hesam; Mohammadpanah, Mahmood

    2018-04-01

    An ultra-wideband (UWB) bandpass filter with ultra-wide stopband based on a rectangular ring resonator is presented. The filter is designed for the operational frequency band from 4.10 GHz to 10.80 GHz with an ultra-wide stopband from 11.23 GHz to 40 GHz. The even and odd equivalent circuits are used to achieve a suitable analysis of the proposed filter performance. To verify the design and analysis, the proposed bandpass filter is simulated using full-wave EM simulator Advanced Design System and fabricated on a 20mil thick Rogers_RO4003 substrate with relative permittivity of 3.38 and a loss tangent of 0.0021. The proposed filter behavior is investigated and simulation results are in good agreement with measurement results.

  19. MTF measurement and analysis of linear array HgCdTe infrared detectors

    Science.gov (United States)

    Zhang, Tong; Lin, Chun; Chen, Honglei; Sun, Changhong; Lin, Jiamu; Wang, Xi

    2018-01-01

    The slanted-edge technique is the main method for measurement detectors MTF, however this method is commonly used on planar array detectors. In this paper the authors present a modified slanted-edge method to measure the MTF of linear array HgCdTe detectors. Crosstalk is one of the major factors that degrade the MTF value of such an infrared detector. This paper presents an ion implantation guard-ring structure which was designed to effectively absorb photo-carriers that may laterally defuse between adjacent pixels thereby suppressing crosstalk. Measurement and analysis of the MTF of the linear array detectors with and without a guard-ring were carried out. The experimental results indicated that the ion implantation guard-ring structure effectively suppresses crosstalk and increases MTF value.

  20. TRIBOLOGICAL PERFORMANCE OF PISTON RING IN MARINE DIESEL ENGINE

    DEFF Research Database (Denmark)

    Imran, Tajammal; Klit, Peder; Felter, Christian

    From a tribology point of view, it is the two dead centers that are the main area of interest for experimental study of piston rings in large marine diesel engines. Therefore, in this work the performance of piston rings is studied to mark the importance of the two dead centers. A test rig based...

  1. Tricking the guard: exploiting plant defense for disease susceptibility.

    Science.gov (United States)

    Lorang, J; Kidarsa, T; Bradford, C S; Gilbert, B; Curtis, M; Tzeng, S-C; Maier, C S; Wolpert, T J

    2012-11-02

    Typically, pathogens deploy virulence effectors to disable defense. Plants defeat effectors with resistance proteins that guard effector targets. We found that a pathogen exploits a resistance protein by activating it to confer susceptibility in Arabidopsis. The guard mechanism of plant defense is recapitulated by interactions among victorin (an effector produced by the necrotrophic fungus Cochliobolus victoriae), TRX-h5 (a defense-associated thioredoxin), and LOV1 (an Arabidopsis susceptibility protein). In LOV1's absence, victorin inhibits TRX-h5, resulting in compromised defense but not disease by C. victoriae. In LOV1's presence, victorin binding to TRX-h5 activates LOV1 and elicits a resistance-like response that confers disease susceptibility. We propose that victorin is, or mimics, a conventional pathogen virulence effector that was defeated by LOV1 and confers virulence to C. victoriae solely because it incites defense.

  2. High Temperature Capacitive Pressure Sensor Employing a SiC Based Ring Oscillator

    Science.gov (United States)

    Meredith, Roger D.; Neudeck, Philip G.; Ponchak, George E.; Beheim, Glenn M.; Scardelletti, Maximilian; Jordan, Jennifer L.; Chen, Liang-Yu; Spry, David J.; Krawowski, Michael J.; Hunter, Gary W.

    2011-01-01

    In an effort to develop harsh environment electronic and sensor technologies for aircraft engine safety and monitoring, we have used capacitive-based pressure sensors to shift the frequency of a SiC-electronics-based oscillator to produce a pressure-indicating signal that can be readily transmitted, e.g. wirelessly, to a receiver located in a more benign environment. Our efforts target 500 C, a temperature well above normal operating conditions of commercial circuits but within areas of interest in aerospace engines, deep mining applications and for future missions to the Venus atmosphere. This paper reports for the first time a ring oscillator circuit integrated with a capacitive pressure sensor, both operating at 500 C. This demonstration represents a significant step towards a wireless pressure sensor that can operate at 500 C and confirms the viability of 500 C electronic sensor systems.

  3. Containing Ebola at the Source with Ring Vaccination.

    Directory of Open Access Journals (Sweden)

    Stefano Merler

    2016-11-01

    Full Text Available Interim results from the Guinea Ebola ring vaccination trial suggest high efficacy of the rVSV-ZEBOV vaccine. These findings open the door to the use of ring vaccination strategies in which the contacts and contacts of contacts of each index case are promptly vaccinated to contain future Ebola virus disease outbreaks. To provide a numerical estimate of the effectiveness of ring vaccination strategies we introduce a spatially explicit agent-based model to simulate Ebola outbreaks in the Pujehun district, Sierra Leone, structurally similar to previous modelling approaches. We find that ring vaccination can successfully contain an outbreak for values of the effective reproduction number up to 1.6. Through an extensive sensitivity analysis of parameters characterising the readiness and capacity of the health care system, we identify interventions that, alongside ring vaccination, could increase the likelihood of containment. In particular, shortening the time from symptoms onset to hospitalisation to 2-3 days on average through improved contact tracing procedures, adding a 2km spatial component to the vaccination ring, and decreasing human mobility by quarantining affected areas might contribute increase our ability to contain outbreaks with effective reproduction number up to 2.6. These results have implications for future control of Ebola and other emerging infectious disease threats.

  4. Some Aspects of Ring Theory

    CERN Document Server

    Herstein, IN

    2011-01-01

    S. Amitsur: Associative rings with identities.- I.N. Herstein: Topics in ring theory.- N. Jacobson: Representation theory of Jordan algebras.- I. Kaplansky: The theory of homological dimension.- D. Buchsbaum: Complexes in local ring theory.- P.H. Cohn: Two topics in ring theory.- A.W. Goldie: Non-commutative localisation.

  5. Radiation safety design for SSRL storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Khater, Hesham [Radiation Protection Department, Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)]. E-mail: khater1@llnl.gov; Liu, James [Radiation Protection Department, Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Fasso, Alberto [Radiation Protection Department, Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Prinz, Alyssa [Radiation Protection Department, Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Rokni, Sayed [Radiation Protection Department, Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)

    2006-12-15

    In 2003, the Stanford Synchrotron Radiation Laboratory (SSRL) had upgraded its storage ring to a 3rd generation storage ring (SPEAR3). SPEAR3 is deigned to operate at 500-mA stored beam current and 3-GeV energy. The 234-m circumference SPEAR3 ring utilizes 60-cm-thick concrete lateral walls, 30-cm-thick concrete roof, as well as 60- or 90-cm-thick concrete ratchet walls. A total of 3.5x10{sup 15}e{sup -}/y will be injected into the ring with an injection power of 4W and an injection efficiency of 75%. Normal beam losses occur due to both injection and stored beam operations in the total of 20 low loss as well as 3 high loss limiting apertures. During the 6-min injection period, an instantaneous power loss of 0.05W occurs at each low loss aperture. When averaged over the operational year, the loss of both the injection and the stored beams is equivalent to an average loss of 2mW at each low loss aperture. On the other hand, the average losses in the high loss apertures are 16mW for the injection septum, 47mW for the beam abort dump, and 13mW for the ring stoppers. The shielding requirements for losses in the new ring were based on a generic approach that used both FLUKA Monte Carlo particle generation and transport code and empirical computer codes and formulae.

  6. 20 CFR 1002.306 - Is a National Guard civilian technician considered a State or Federal employee for purposes of...

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Is a National Guard civilian technician... a National Guard civilian technician considered a State or Federal employee for purposes of USERRA? A National Guard civilian technician is considered a State employee for USERRA purposes, although he...

  7. Improving the Accuracy of Laplacian Estimation with Novel Variable Inter-Ring Distances Concentric Ring Electrodes

    Directory of Open Access Journals (Sweden)

    Oleksandr Makeyev

    2016-06-01

    Full Text Available Noninvasive concentric ring electrodes are a promising alternative to conventional disc electrodes. Currently, the superiority of tripolar concentric ring electrodes over disc electrodes, in particular, in accuracy of Laplacian estimation, has been demonstrated in a range of applications. In our recent work, we have shown that accuracy of Laplacian estimation can be improved with multipolar concentric ring electrodes using a general approach to estimation of the Laplacian for an (n + 1-polar electrode with n rings using the (4n + 1-point method for n ≥ 2. This paper takes the next step toward further improving the Laplacian estimate by proposing novel variable inter-ring distances concentric ring electrodes. Derived using a modified (4n + 1-point method, linearly increasing and decreasing inter-ring distances tripolar (n = 2 and quadripolar (n = 3 electrode configurations are compared to their constant inter-ring distances counterparts. Finite element method modeling and analytic results are consistent and suggest that increasing inter-ring distances electrode configurations may decrease the truncation error resulting in more accurate Laplacian estimates compared to respective constant inter-ring distances configurations. For currently used tripolar electrode configuration, the truncation error may be decreased more than two-fold, while for the quadripolar configuration more than a six-fold decrease is expected.

  8. Improving the Accuracy of Laplacian Estimation with Novel Variable Inter-Ring Distances Concentric Ring Electrodes

    Science.gov (United States)

    Makeyev, Oleksandr; Besio, Walter G.

    2016-01-01

    Noninvasive concentric ring electrodes are a promising alternative to conventional disc electrodes. Currently, the superiority of tripolar concentric ring electrodes over disc electrodes, in particular, in accuracy of Laplacian estimation, has been demonstrated in a range of applications. In our recent work, we have shown that accuracy of Laplacian estimation can be improved with multipolar concentric ring electrodes using a general approach to estimation of the Laplacian for an (n + 1)-polar electrode with n rings using the (4n + 1)-point method for n ≥ 2. This paper takes the next step toward further improving the Laplacian estimate by proposing novel variable inter-ring distances concentric ring electrodes. Derived using a modified (4n + 1)-point method, linearly increasing and decreasing inter-ring distances tripolar (n = 2) and quadripolar (n = 3) electrode configurations are compared to their constant inter-ring distances counterparts. Finite element method modeling and analytic results are consistent and suggest that increasing inter-ring distances electrode configurations may decrease the truncation error resulting in more accurate Laplacian estimates compared to respective constant inter-ring distances configurations. For currently used tripolar electrode configuration, the truncation error may be decreased more than two-fold, while for the quadripolar configuration more than a six-fold decrease is expected. PMID:27294933

  9. U.S. Coast Guard (USCG) Maritime Differential GPS (DGPS) Locations

    Data.gov (United States)

    Department of Homeland Security — NAVCEN operates the Coast Guard Maritime Differential GPS (DGPS) Service and the developing Nationwide DGPS Service (NDGPS), consisting of two control centers and 86...

  10. Examining Ankle-Joint Laxity Using 2 Knee Positions and With Simulated Muscle Guarding.

    Science.gov (United States)

    Hanlon, Shawn; Caccese, Jaclyn; Knight, Christopher A; Swanik, Charles Buz; Kaminski, Thomas W

    2016-02-01

    Several factors affect the reliability of the anterior drawer and talar tilt tests, including the individual clinician's experience and skill, ankle and knee positioning, and muscle guarding. To compare gastrocnemius activity during the measurement of ankle-complex motion at different knee positions, and secondarily, to compare ankle-complex motion during a simulated trial of muscle guarding. Cross-sectional study. Research laboratory. Thirty-three participants aged 20.2 ± 1.7 years were tested. The ankle was loaded under 2 test conditions (relaxed, simulated muscle guarding) at 2 knee positions (0°, 90° of flexion) while gastrocnemius electromyography (EMG) activity was recorded. Anterior displacement (mm), inversion-eversion motion (°), and peak EMG amplitude values of the gastrocnemius (μV). Anterior displacement did not differ between the positions of 0° and 90° of knee flexion (P = .193). Inversion-eversion motion was greater at 0° of knee flexion compared with 90° (P ankle laxity at the 2 most common knee positions for anterior drawer testing; however, talar tilt testing may be best performed with the knee in 0° of knee flexion. Finally, our outcomes from the simulated muscle-guarding condition suggest that clinicians should use caution and be aware of reduced perceived laxity when performing these clinical examination techniques immediately postinjury.

  11. Small incision guarded hydroaspiration of iris lesions.

    Science.gov (United States)

    Singh, Arun D

    2017-11-01

    To describe the technique and results of a minimally invasive surgical technique for resection of small iris lesions. Consecutive case series of 22 patients with localised, small iris lesions that were resected using the described surgical technique that composed of multiple, small corneal incisions created to allow for internal iris resection with 23-gauge horizontal vitrectomy scissors, followed by guarded tumour aspiration through a clear plastic tubing (diameter 3.5 mm) primed with viscoelastic agent. The mean largest basal diameter was 3.0 mm (range 1.5-5.0 mm; median 3.0 mm) and mean thickness was 1.3 mm (range 0.5-2.5 mm; median 1.0 mm). Use of multiple (2-4) small corneal incisions (range 2.0-3.0 mm; mean 2.8 mm) allowed reduced postoperative morbidity (significant hyphema (0%), hypotony (0%), wound leak (0%), >2 line change in best corrected visual acuity at postoperative 1 week (4.5%) and mean corneal astigmatism of 1.0 D (range 0.14-2.99 D; median 0.8 D) at postoperative 4-12 weeks. The tumour could be resected with clear surgical margins in all neoplastic cases (benign (2), borderline (1) and malignant (16)). Local recurrence or metastases were not observed in any melanoma case over a mean follow-up of 33.0 months (range 1.0-90.0 months; median 33.5 months). Small incision guarded hydroaspiration is a minimally invasive surgical technique for resection of select small iris lesions. Use of multiple small corneal incisions avoids morbidity associated with a single large corneoscleral incision, and use of guarded aspiration may eliminate the risk of wound contamination by the malignant tumour. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  12. Study of improvement in 1st ring`s gas-seal; Top ring no gas seal seino kojo no kento

    Energy Technology Data Exchange (ETDEWEB)

    Ando, H; Tateishi, Y; Fujimura, K; Hitosugi, H [Nippon Piston Ring Co. Ltd., Tokyo (Japan)

    1997-10-01

    The authors studied the effect of an angle of 1st ring twist on the amount of blow-by concerning higher speed/higher output engines for motorcycles. As a result, the authors found the twist made the ring restrained in a ring groove of piston , and confirmed its suitable range for blow-by. By means of the developed optimization method, the authors have achieved significant reduction in blow-by at high engine speed. 1 ref., 9 figs., 2 tabs.

  13. Radiocarbon measurements of tree-ring samples from Japanese woods

    International Nuclear Information System (INIS)

    Ozaki, Hiromasa; Sakamoto, Minoru; Imamura, Mineo; Mitsutani, Takumi

    2008-01-01

    Since radiocarbon age is a model age based on constancy of atmospheric radiocarbon concentration and a provisional value of 5568 years for the 14 C half-life, calibration to calendar age is required for practical dating. The dataset, called IntCal, used for the calibration has been constructed by international consortium. Most parts of the IntCal have been based on the measurement of radiocarbon in dendrochronologically dated tree-ring samples from woods in Europe and North America. Regional offsets, which are designed as differences of local atmospheric radiocarbon from IntCal, have been pointed out based on recent radiocarbon measurements for tree-ring samples from a few regions. We have also measured radiocarbon of tree-ring samples from Japanese woods in order to investigate regional offsets in Japan. In this study, radiocarbon measurements for tree-ring samples from three different Japanese woods at around AD500 were carried out. Consequently, differences from IntCal04 at around AD500 were confirmed, although no systematic offset are found. However, the results obtained in this study agree with the raw data used for construction of IntCal04. This could pose a question to calculation method of IntCal04. (author)

  14. Viscosity of ring polymer melts

    KAUST Repository

    Pasquino, Rossana

    2013-10-15

    We have measured the linear rheology of critically purified ring polyisoprenes, polystyrenes, and polyethyleneoxides of different molar masses. The ratio of the zero-shear viscosities of linear polymer melts η0,linear to their ring counterparts η0,ring at isofrictional conditions is discussed as a function of the number of entanglements Z. In the unentangled regime η0,linear/η 0,ring is virtually constant, consistent with the earlier data, atomistic simulations, and the theoretical expectation η0,linear/ η0,ring = 2. In the entanglement regime, the Z-dependence of ring viscosity is much weaker than that of linear polymers, in qualitative agreement with predictions from scaling theory and simulations. The power-law extracted from the available experimental data in the rather limited range 1 < Z < 20, η0,linear/η0,ring ∼ Z 1.2±0.3, is weaker than the scaling prediction (η0,linear/η0,ring ∼ Z 1.6±0.3) and the simulations (η0,linear/ η0,ring ∼ Z2.0±0.3). Nevertheless, the present collection of state-of-the-art experimental data unambiguously demonstrates that rings exhibit a universal trend clearly departing from that of their linear counterparts, and hence it represents a major step toward resolving a 30-year-old problem. © 2013 American Chemical Society.

  15. Viscosity of ring polymer melts

    KAUST Repository

    Pasquino, Rossana; Vasilakopoulos, Thodoris C.; Jeong, Youncheol; Lee, Hyojoon; Rogers, Simon A.; Sakellariou, Georgios; Allgaier, Jü rgen B.; Takano, Atsushi; Brá s, Ana Rita E; Chang, Taihyun; Gooß en, Sebastian; Pyckhout-Hintzen, Wim; Wischnewski, Andreas; Hadjichristidis, Nikolaos; Richter, Dieter R.; Rubinstein, Michael H.; Vlassopoulos, Dimitris

    2013-01-01

    We have measured the linear rheology of critically purified ring polyisoprenes, polystyrenes, and polyethyleneoxides of different molar masses. The ratio of the zero-shear viscosities of linear polymer melts η0,linear to their ring counterparts η0,ring at isofrictional conditions is discussed as a function of the number of entanglements Z. In the unentangled regime η0,linear/η 0,ring is virtually constant, consistent with the earlier data, atomistic simulations, and the theoretical expectation η0,linear/ η0,ring = 2. In the entanglement regime, the Z-dependence of ring viscosity is much weaker than that of linear polymers, in qualitative agreement with predictions from scaling theory and simulations. The power-law extracted from the available experimental data in the rather limited range 1 < Z < 20, η0,linear/η0,ring ∼ Z 1.2±0.3, is weaker than the scaling prediction (η0,linear/η0,ring ∼ Z 1.6±0.3) and the simulations (η0,linear/ η0,ring ∼ Z2.0±0.3). Nevertheless, the present collection of state-of-the-art experimental data unambiguously demonstrates that rings exhibit a universal trend clearly departing from that of their linear counterparts, and hence it represents a major step toward resolving a 30-year-old problem. © 2013 American Chemical Society.

  16. Isomorphism Theorem on Vector Spaces over a Ring

    Directory of Open Access Journals (Sweden)

    Futa Yuichi

    2017-10-01

    Full Text Available In this article, we formalize in the Mizar system [1, 4] some properties of vector spaces over a ring. We formally prove the first isomorphism theorem of vector spaces over a ring. We also formalize the product space of vector spaces. ℤ-modules are useful for lattice problems such as LLL (Lenstra, Lenstra and Lovász [5] base reduction algorithm and cryptographic systems [6, 2].

  17. ring og refleksion

    DEFF Research Database (Denmark)

    Wahlgren, B.; Rattleff, Pernille; Høyrup, S.

    State of the art inden for forskning om læring på arbejdspladsen samt gennemgang af læringsteori og refleksionsbegrebet hos Dewey, Dreyfus, Schön, Argyris, Kolb, Jarvis, Mezirow og Brookfield. Afsluttes med diskussion af syntetiseret model for læring på arbejdspladsen.......State of the art inden for forskning om læring på arbejdspladsen samt gennemgang af læringsteori og refleksionsbegrebet hos Dewey, Dreyfus, Schön, Argyris, Kolb, Jarvis, Mezirow og Brookfield. Afsluttes med diskussion af syntetiseret model for læring på arbejdspladsen....

  18. Digital power and performance analysis of inkjet printed ring oscillators based on electrolyte-gated oxide electronics

    Science.gov (United States)

    Cadilha Marques, Gabriel; Garlapati, Suresh Kumar; Dehm, Simone; Dasgupta, Subho; Hahn, Horst; Tahoori, Mehdi; Aghassi-Hagmann, Jasmin

    2017-09-01

    Printed electronic components offer certain technological advantages over their silicon based counterparts, like mechanical flexibility, low process temperatures, maskless and additive manufacturing possibilities. However, to be compatible to the fields of smart sensors, Internet of Things, and wearables, it is essential that devices operate at small supply voltages. In printed electronics, mostly silicon dioxide or organic dielectrics with low dielectric constants have been used as gate isolators, which in turn have resulted in high power transistors operable only at tens of volts. Here, we present inkjet printed circuits which are able to operate at supply voltages as low as ≤2 V. Our transistor technology is based on lithographically patterned drive electrodes, the dimensions of which are carefully kept well within the printing resolutions; the oxide semiconductor, the electrolytic insulator and the top-gate electrodes have been inkjet printed. Our inverters show a gain of ˜4 and 2.3 ms propagation delay time at 1 V supply voltage. Subsequently built 3-stage ring oscillators start to oscillate at a supply voltage of only 0.6 V with a frequency of ˜255 Hz and can reach frequencies up to ˜350 Hz at 2 V supply voltage. Furthermore, we have introduced a systematic methodology for characterizing ring oscillators in the printed electronics domain, which has been largely missing. Benefiting from this procedure, we are now able to predict the switching capacitance and driver capability at each stage, as well as the power consumption of our inkjet printed ring oscillators. These achievements will be essential for analyzing the performance and power characteristics of future inkjet printed digital circuits.

  19. Birth Control Ring

    Science.gov (United States)

    ... Health Food & Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español Birth Control Ring KidsHealth / For Teens / Birth Control Ring What's ...

  20. Electrical conductivity of sandstone, limestone, and granite

    Energy Technology Data Exchange (ETDEWEB)

    Duba, A.; Piwinskii, A.J.; Santor, M.; Weed, H.C.

    1978-01-01

    The electrical conductivity of cylindrical cores of Westerly granite, Indiana limestone and Nugget, St Peter and Kayenta sandstones was measured at about 25/sup 0/C in vacuo, in air, and after saturation in distilled water, tap water, and 0.1 M NaCl solution. The three-electrode technique with a guard ring and the two-electrode technique without a guard ring were used. Core aspect ratio over the range of 2.00 to 0.25, as well as frequency over the range of 50 Hz to 10 kHz, influences the conductivity of all rocks, especially those measured in vacuo. Measurements from water-saturated samples using a guard ring are not appreciably different from those obtained without a guard ring. The conductivity of rocks saturated in 0.1 M NaCl solution changes least with a change in aspect ratio; for these rocks a linear relationship, known as Archie's Law, exists between log porosity and log conductivity. No simple correlation was found between those factors in rocks saturated with tap or distilled water. Thus, it appears Archie's Law is of questionable value for correlating laboratory data from rocks saturated with low-conductivity fluids.

  1. Task force St. Bernard: operational issues and medical management of a National Guard disaster response operation.

    Science.gov (United States)

    Bonnett, Carl J; Schock, Tony R; McVaney, Kevin E; Colwell, Christopher B; Depass, Christopher

    2007-01-01

    After Hurricane Katrina struck the Gulf Coast of the United States on 29 August 2005, it became obvious that the country was facing an enormous national emergency. With local resources overwhelmed, governors across the US responded by deploying thousands of National Guard soldiers and airmen. The National Guard has responded to domestic disasters due to natural hazards since its inception, but an event with the magnitude of Hurricane Katrina was unprecedented. The deployment of >900 Army National Guard soldiers to St. Bernard Parish, Louisiana in the aftermath of the Hurricane was studied to present some of the operational issues involved with providing medical support for this type of operation. In doing so, the authors attempt to address some of the larger issues of how the National Guard can be incorporated into domestic disaster response efforts. A number of unforeseen issues with regards to medical operations, medical supply, communication, preventive medicine, legal issues, and interactions with civilians were encountered and are reviewed. A better understanding of the National Guard and how it can be utilized more effectively in future disaster response operations can be developed.

  2. From coffee ring to spherulites ring of poly(ethylene oxide) film from drying droplet

    Science.gov (United States)

    Hu, Yinchun; Zhang, Xuerong; Qiu, Maibo; Wei, Yan; Zhou, Qiong; Huang, Di

    2018-03-01

    We discuss how the "spherulites ring" morphology and "coffee ring" profile of PEO film formed by the drying droplet at glass substrate with different heating rate. Upon increasing the heating rate of substrate, it is found that deposited PEO film from drying droplet shows the unusually observed "coffee ring" profile and "spherulites ring" morphology. The main mechanism for this phenomenon is proposed to be an enhanced Marangoni convection which is induced by the increased solute concentration gradient and reduced viscous force above 70 °C. A simple formation mechanism of the unusually observed "coffee ring" profile and "spherulites ring" morphology is proposed. These findings can be exploited to trace the center of Marangoni convection, with potential applications in designing the spherulite patterns of crystalline polymer films in ink-jet printing and self-assembly fields.

  3. Systematic Search for Rings around Kepler Planet Candidates: Constraints on Ring Size and Occurrence Rate

    Science.gov (United States)

    Aizawa, Masataka; Masuda, Kento; Kawahara, Hajime; Suto, Yasushi

    2018-05-01

    We perform a systematic search for rings around 168 Kepler planet candidates with sufficient signal-to-noise ratios that are selected from all of the short-cadence data. We fit ringed and ringless models to their light curves and compare the fitting results to search for the signatures of planetary rings. First, we identify 29 tentative systems, for which the ringed models exhibit statistically significant improvement over the ringless models. The light curves of those systems are individually examined, but we are not able to identify any candidate that indicates evidence for rings. In turn, we find several mechanisms of false positives that would produce ringlike signals, and the null detection enables us to place upper limits on the size of the rings. Furthermore, assuming the tidal alignment between axes of the planetary rings and orbits, we conclude that the occurrence rate of rings larger than twice the planetary radius is less than 15%. Even though the majority of our targets are short-period planets, our null detection provides statistical and quantitative constraints on largely uncertain theoretical models of the origin, formation, and evolution of planetary rings.

  4. Vibration of Elastic Functionally Graded Thick Rings

    Directory of Open Access Journals (Sweden)

    Guang-Hui Xu

    2017-01-01

    Full Text Available The free vibration behaviors of functionally graded rings were investigated theoretically. The material graded in the thickness direction according to the power law rule and the rings were assumed to be in plane stress and plane strain states. Based on the first-order shear deformation theory and the kinetic relation of von Kárman type, the frequency equation for free vibration of functionally graded ring was derived. The derived results were verified by those in literatures which reveals that the present theory can be appropriate to predict the free vibration characteristics for quite thick rings with the radius-to-thickness ratio from 60 down to 2.09. Comparison between the plane stress case and the plane strain case indicates a slight difference. Meanwhile, the effects of the structural dimensional parameters and the material inhomogeneous parameter are examined. It is interesting that the value of the logarithmic form of vibration frequency is inversely proportional to the logarithmic form of the radius-to-thickness ratio or the mean radius.

  5. An algorithm and a Tool for Wavelength Allocation in OMS-SP Ring Architecture

    DEFF Research Database (Denmark)

    Riaz, Muhammad Tahir; Pedersen, Jens Myrup; Madsen, Ole Brun

    2006-01-01

    OMS-SP ring is one of the well known architectures in Wavelength Division Multiplexing based optical fiber networks. The architecture supports a restorable full mesh in an optical fiber ring using multiple light wavelengths. The paper presents an algorithm to allocate wavelengths in the OMS-SP ri...... architecture. A tool is also introduced which implements the algorithm and assigns wavelengths. The proposed algorithm uses fewer number of wavelengths than the classical allocation method. The algorithm is described and results are presented.......OMS-SP ring is one of the well known architectures in Wavelength Division Multiplexing based optical fiber networks. The architecture supports a restorable full mesh in an optical fiber ring using multiple light wavelengths. The paper presents an algorithm to allocate wavelengths in the OMS-SP ring...

  6. 77 FR 35855 - Safety Zone, Temporary Change for Recurring Fifth Coast Guard District Fireworks Displays...

    Science.gov (United States)

    2012-06-15

    ... 1625-AA00 Safety Zone, Temporary Change for Recurring Fifth Coast Guard District Fireworks Displays; Northwest Harbor (East Channel) and Tred Avon River, MD AGENCY: Coast Guard, DHS. ACTION: Temporary final... Channel), Patapsco River, and Tred Avon River during the event. DATES: This rule is effective from 8 p.m...

  7. A giant magnetoresistance ring-sensor based microsystem for magnetic bead manipulation and detection

    KAUST Repository

    Gooneratne, Chinthaka P.

    2011-03-28

    In this paper a novel spin valvegiant magnetoresistance(GMR) ring-sensor integrated with a microstructure is proposed for concentrating, trapping, and detecting superparamagnetic beads (SPBs). Taking advantage of the fact that SPBs can be manipulated by an external magnetic field, a unique arrangement of conducting microrings is utilized to manipulate the SPBs toward the GMR sensing area in order to increase the reliability of detection. The microrings are arranged and activated in such a manner so as to enable the detection of minute concentrations of SPBs in a sample. Precise manipulation is achieved by applying current sequentially to the microrings. The fabricated ring-shaped GMR element is located underneath the innermost ring and has a magnetoresistance of approximately 5.9%. By the performed experiments it was shown that SPBs could be successfully manipulated toward the GMR sensing zone.

  8. A giant magnetoresistance ring-sensor based microsystem for magnetic bead manipulation and detection

    KAUST Repository

    Gooneratne, Chinthaka P.; Giouroudi, Ioanna; Liang, Cai; Kosel, Jü rgen

    2011-01-01

    In this paper a novel spin valvegiant magnetoresistance(GMR) ring-sensor integrated with a microstructure is proposed for concentrating, trapping, and detecting superparamagnetic beads (SPBs). Taking advantage of the fact that SPBs can be manipulated by an external magnetic field, a unique arrangement of conducting microrings is utilized to manipulate the SPBs toward the GMR sensing area in order to increase the reliability of detection. The microrings are arranged and activated in such a manner so as to enable the detection of minute concentrations of SPBs in a sample. Precise manipulation is achieved by applying current sequentially to the microrings. The fabricated ring-shaped GMR element is located underneath the innermost ring and has a magnetoresistance of approximately 5.9%. By the performed experiments it was shown that SPBs could be successfully manipulated toward the GMR sensing zone.

  9. Structure and dynamics of ringed galaxies

    International Nuclear Information System (INIS)

    Buta, R.J.

    1984-01-01

    In many spiral and SO galaxies, single or multiple ring structures are visible in the disk. These inner rings (r), outer rings (R), and nuclear rings (nr) were investigated by means of morphology, photometry, and spectroscopy in order to provide basic data on a long neglected phenomenon. The metric properties of each ring are investigated and found to correlate with the structure of the parent galaxy. When properly calibrated, inner rings in barred (SB) systems can be used as geometric extragalactic distance indicators to distances in excess of 100 Mpc. Other statistics are presented that confirm previous indications that the rings have preferred shapes, relative sizes, and orientations with respect to bars. A survey is made of the less homogeneous non-barred (SA) ringed systems, and the causes of the inhomogeneity are isolated. It is shown that rings can be identified in multiple-ring SA systems that are exactly analogous to those in barred spirals

  10. [Burnout Syndrome in Prison Guards, Bucaramanga, Colombia, 2013].

    Science.gov (United States)

    Rodríguez Amaya, Reynaldo Mauricio

    2014-01-01

    Burnout syndrome is defined as a chronic stress response and sustained work environment, characterized by emotional exhaustion, depersonalization and personal accomplishment. Most studies have included teaching and health personnel. However, there are limitations in the development of studies on prison guards to observe this problem. This study provides some characteristics of prison guards and seeks to highlight the behavior of the constructs of burnout according to demographic and occupational profile. This was a descriptive cross-sectional study on 111 prison guards in the city of Bucaramanga. The Maslach Burnout Inventory was applied, as well as taking ethical considerations into account. A univariate and bivariate analysis was performed on the data. The mean age was 35.8 years, 76% had more than 10 years work experience, 24% have some additional academic activities at work. Only 3.7% had burnout syndrome as such. In emotional exhaustion, 25.2% are classified as high risk, 30% in depersonalization, and 16% personal accomplishment. Within the personal achievement, the group with more than 20 years experience were those who had a critical score (ANOVA χ(2), P=.002). Of those who had a risk score for depersonalization, 67% had worked more than 240 extra hours a month, with a crude odds ratio (OR)=4.66 (P=.033) and age-adjusted OR=4.65 (P=.035). Burnout in this occupational group was not as prevalent as in that found in other publications. In turn, of the three constructs, the most significant was depersonalization and no notable emotional burnout was observed. The most significant work variables were the number of hours worked and work experience. Copyright © 2013 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  11. Influencia de la lateralidad dominante de la jugadora en puesto específico de base en el juego de ataque en Liga Femenina 2 [Laterality dominance of female point guard influences in the offensive patterns in LF2

    Directory of Open Access Journals (Sweden)

    Alejandra Manzano Rivera

    2010-03-01

    Full Text Available Resumen La lateralidad de la jugadora con el rol de base puede ser sólo una característica individual, o bien un factor influyente en el juego de su equipo, y por tanto, una herramienta a considerar por  parte del equipo rival. El trabajo de investigación se centra en la necesidad de reflejar si la lateralidad de una jugadora con rol de base en baloncesto, al iniciar la acción de juego (bote o pase influye de manera determinante en la toma de decisiones. El contexto de trabajo utilizado es la segunda categoría de baloncesto femenino nacional, Liga Femenina 2. En la observación han participado varios equipos de dicha categoría, con total de 10 partidos analizados y un total de 170 situaciones de juego analizadas (N=170. Para establecer las relaciones entre las variables se utilizó el Coeficiente de Contingencia. Los resultados muestran una relación estadísticamente significativa de la lateralidad de la base y el lado del campo en el que se empieza a jugar (c2(1, N=170 = 4.789, pPalabras clave: Baloncesto, Lateralidad, Base, Análisis de juego.   AbstractLaterality of the point-guard can be an individual characteristic, or in the other hand, an important factor in the offensive patterns of the team. In this way, it will be a useful information for the other team.  This research has focused in the laterality of the point guard, and it influences in the decision making. The League studied was the second female Spanish basketball league, LF2. 10 matches were observed and 170 game situations analyzed (N=170. Crosstabs Command and the Contingency Coefficient were used to establish the relationship between variables. The results shows a significant relationship between the laterality of the point guard and the side of the field where the attack begin (c2(1, N=170 = 4.789, pKey words:  Basketball, laterality, point guard, game analysis.

  12. A novel image encryption algorithm based on synchronized random bit generated in cascade-coupled chaotic semiconductor ring lasers

    Science.gov (United States)

    Li, Jiafu; Xiang, Shuiying; Wang, Haoning; Gong, Junkai; Wen, Aijun

    2018-03-01

    In this paper, a novel image encryption algorithm based on synchronization of physical random bit generated in a cascade-coupled semiconductor ring lasers (CCSRL) system is proposed, and the security analysis is performed. In both transmitter and receiver parts, the CCSRL system is a master-slave configuration consisting of a master semiconductor ring laser (M-SRL) with cross-feedback and a solitary SRL (S-SRL). The proposed image encryption algorithm includes image preprocessing based on conventional chaotic maps, pixel confusion based on control matrix extracted from physical random bit, and pixel diffusion based on random bit stream extracted from physical random bit. Firstly, the preprocessing method is used to eliminate the correlation between adjacent pixels. Secondly, physical random bit with verified randomness is generated based on chaos in the CCSRL system, and is used to simultaneously generate the control matrix and random bit stream. Finally, the control matrix and random bit stream are used for the encryption algorithm in order to change the position and the values of pixels, respectively. Simulation results and security analysis demonstrate that the proposed algorithm is effective and able to resist various typical attacks, and thus is an excellent candidate for secure image communication application.

  13. Expression of Arabidopsis Hexokinase in Citrus Guard Cells Controls Stomatal Aperture and Reduces Transpiration.

    Science.gov (United States)

    Lugassi, Nitsan; Kelly, Gilor; Fidel, Lena; Yaniv, Yossi; Attia, Ziv; Levi, Asher; Alchanatis, Victor; Moshelion, Menachem; Raveh, Eran; Carmi, Nir; Granot, David

    2015-01-01

    Hexokinase (HXK) is a sugar-phosphorylating enzyme involved in sugar-sensing. It has recently been shown that HXK in guard cells mediates stomatal closure and coordinates photosynthesis with transpiration in the annual species tomato and Arabidopsis. To examine the role of HXK in the control of the stomatal movement of perennial plants, we generated citrus plants that express Arabidopsis HXK1 (AtHXK1) under KST1, a guard cell-specific promoter. The expression of KST1 in the guard cells of citrus plants has been verified using GFP as a reporter gene. The expression of AtHXK1 in the guard cells of citrus reduced stomatal conductance and transpiration with no negative effect on the rate of photosynthesis, leading to increased water-use efficiency. The effects of light intensity and humidity on stomatal behavior were examined in rooted leaves of the citrus plants. The optimal intensity of photosynthetically active radiation and lower humidity enhanced stomatal closure of AtHXK1-expressing leaves, supporting the role of sugar in the regulation of citrus stomata. These results suggest that HXK coordinates photosynthesis and transpiration and stimulates stomatal closure not only in annual species, but also in perennial species.

  14. National Guard Engagement in the Pacific: No Threat to Security

    National Research Council Canada - National Science Library

    Bour, Mark

    2002-01-01

    This thesis evaluates recent decisions to expand the National Guard (NGE) State Partnership Program into the Asia-Pacific region and examines potential effects this expansion will have on the new partners created...

  15. Multiplicative Structure and Hecke Rings of Generator Matrices for Codes over Quotient Rings of Euclidean Domains

    Directory of Open Access Journals (Sweden)

    Hajime Matsui

    2017-12-01

    Full Text Available In this study, we consider codes over Euclidean domains modulo their ideals. In the first half of the study, we deal with arbitrary Euclidean domains. We show that the product of generator matrices of codes over the rings mod a and mod b produces generator matrices of all codes over the ring mod a b , i.e., this correspondence is onto. Moreover, we show that if a and b are coprime, then this correspondence is one-to-one, i.e., there exist unique codes over the rings mod a and mod b that produce any given code over the ring mod a b through the product of their generator matrices. In the second half of the study, we focus on the typical Euclidean domains such as the rational integer ring, one-variable polynomial rings, rings of Gaussian and Eisenstein integers, p-adic integer rings and rings of one-variable formal power series. We define the reduced generator matrices of codes over Euclidean domains modulo their ideals and show their uniqueness. Finally, we apply our theory of reduced generator matrices to the Hecke rings of matrices over these Euclidean domains.

  16. Breakaway frictions of dynamic O-rings in mechanical seals

    Science.gov (United States)

    Lai, Tom; Kay, Peter

    1993-05-01

    Breakaway friction of a dynamic O-ring affects the mechanical seal's response to large axial shaft movement and face wear. However, little data exist to help designers. Therefore, a test rig was developed to measure breakaway friction. The research quantitatively shows the effects of lubrication with silicone grease and a change of surface finish. By using the Taguchi statistical experimental design method, the significance of test parameters was evaluated with a minimum number of tests. It was found that fluid pressure, dwell time, and O-ring percentage squeeze affect O-ring breakaway friction more than the O-ring cross sectional diameter and axial sliding speed within the range of values tested. The authors showed that breakaway friction increased linearly with pressure. However, O-rings made of different materials had significantly different increase rates, even if they had nominally the same durometer hardness. Breakaway friction also increased with logarithm of dwell time. Again, the increase rate depended strongly on the specific O-ring material tested. These observations led the authors to believe that the typical approach of generalizing data based on generic polymer type and durometer was inappropriate.

  17. A highly sensitive monoclonal antibody based biosensor for quantifying 3–5 ring polycyclic aromatic hydrocarbons (PAHs in aqueous environmental samples

    Directory of Open Access Journals (Sweden)

    Xin Li

    2016-03-01

    Full Text Available Immunoassays based on monoclonal antibodies (mAbs are highly sensitive for the detection of polycyclic aromatic hydrocarbons (PAHs and can be employed to determine concentrations in near real-time. A sensitive generic mAb against PAHs, named as 2G8, was developed by a three-step screening procedure. It exhibited nearly uniformly high sensitivity against 3-ring to 5-ring unsubstituted PAHs and their common environmental methylated PAHs, with IC50 values between 1.68 and 31 μg/L (ppb. 2G8 has been successfully applied on the KinExA Inline Biosensor system for quantifying 3–5 ring PAHs in aqueous environmental samples. PAHs were detected at a concentration as low as 0.2 μg/L. Furthermore, the analyses only required 10 min for each sample. To evaluate the accuracy of the 2G8-based biosensor, the total PAH concentrations in a series of environmental samples analyzed by biosensor and GC–MS were compared. In most cases, the results yielded a good correlation between methods. This indicates that generic antibody 2G8 based biosensor possesses significant promise for a low cost, rapid method for PAH determination in aqueous samples. Keywords: Monoclonal antibody, PAH, Pore water, Biosensor, Pyrene

  18. Finding Their Way Back In: Family Reintegration Following Guard Deployment.

    Science.gov (United States)

    Messecar, Deborah C

    2017-03-01

    The aim of this study was to describe deployed National Guard members' and their families' perceptions of their experience with family reintegration, and the causes and conditions of challenges reintegration presents after deployment. A total of 26 National Guard members and 19 family members participated in individual (n = 22), couples (n = 6), or focus group (n = 17) interviews. In-depth interviews were used to assess needs and maximize input from military families regarding deployment-related experiences and reintegration issues. Qualitative coding and analysis of data were completed using NVivo. Finding their way back in is the key process that the military members must complete to successfully reestablish their desired social connections with the family and reclaim their place within the family. Several conditions shape the degree of challenges with reintegration that veterans and their family will encounter. These include preparation for deployment, length and type of deployment, communication during deployment, and finally, awareness of how deployment changes the military member and the family. Support resources dedicated to providing National Guard members and their families with assistance in preparing for deployments and educating them about the importance of communication during deployment should be maintained and expanded. Broader educational efforts that increase awareness of what to expect regarding how deployment changes the military member and the family are needed. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

  19. Binomial Rings: Axiomatisation, Transfer and Classification

    OpenAIRE

    Xantcha, Qimh Richey

    2011-01-01

    Hall's binomial rings, rings with binomial coefficients, are given an axiomatisation and proved identical to the numerical rings studied by Ekedahl. The Binomial Transfer Principle is established, enabling combinatorial proofs of algebraical identities. The finitely generated binomial rings are completely classified. An application to modules over binomial rings is given.

  20. AN N-BODY INTEGRATOR FOR GRAVITATING PLANETARY RINGS, AND THE OUTER EDGE OF SATURN'S B RING

    International Nuclear Information System (INIS)

    Hahn, Joseph M.; Spitale, Joseph N.

    2013-01-01

    A new symplectic N-body integrator is introduced, one designed to calculate the global 360° evolution of a self-gravitating planetary ring that is in orbit about an oblate planet. This freely available code is called epi i nt, and it is distinct from other such codes in its use of streamlines to calculate the effects of ring self-gravity. The great advantage of this approach is that the perturbing forces arise from smooth wires of ring matter rather than discreet particles, so there is very little gravitational scattering and so only a modest number of particles are needed to simulate, say, the scalloped edge of a resonantly confined ring or the propagation of spiral density waves. The code is applied to the outer edge of Saturn's B ring, and a comparison of Cassini measurements of the ring's forced response to simulations of Mimas's resonant perturbations reveals that the B ring's surface density at its outer edge is σ 0 = 195 ± 60 g cm –2 , which, if the same everywhere across the ring, would mean that the B ring's mass is about 90% of Mimas's mass. Cassini observations show that the B ring-edge has several free normal modes, which are long-lived disturbances of the ring-edge that are not driven by any known satellite resonances. Although the mechanism that excites or sustains these normal modes is unknown, we can plant such a disturbance at a simulated ring's edge and find that these modes persist without any damping for more than ∼10 5 orbits or ∼100 yr despite the simulated ring's viscosity ν s = 100 cm 2 s –1 . These simulations also indicate that impulsive disturbances at a ring can excite long-lived normal modes, which suggests that an impact in the recent past by perhaps a cloud of cometary debris might have excited these disturbances, which are quite common to many of Saturn's sharp-edged rings

  1. Ring rolling process simulation for geometry optimization

    Science.gov (United States)

    Franchi, Rodolfo; Del Prete, Antonio; Donatiello, Iolanda; Calabrese, Maurizio

    2017-10-01

    Ring Rolling is a complex hot forming process where different rolls are involved in the production of seamless rings. Since each roll must be independently controlled, different speed laws must be set; usually, in the industrial environment, a milling curve is introduced to monitor the shape of the workpiece during the deformation in order to ensure the correct ring production. In the present paper a ring rolling process has been studied and optimized in order to obtain anular components to be used in aerospace applications. In particular, the influence of process input parameters (feed rate of the mandrel and angular speed of main roll) on geometrical features of the final ring has been evaluated. For this purpose, a three-dimensional finite element model for HRR (Hot Ring Rolling) has been implemented in SFTC DEFORM V11. The FEM model has been used to formulate a proper optimization problem. The optimization procedure has been implemented in the commercial software DS ISight in order to find the combination of process parameters which allows to minimize the percentage error of each obtained dimension with respect to its nominal value. The software allows to find the relationship between input and output parameters applying Response Surface Methodology (RSM), by using the exact values of output parameters in the control points of the design space explored through FEM simulation. Once this relationship is known, the values of the output parameters can be calculated for each combination of the input parameters. After the calculation of the response surfaces for the selected output parameters, an optimization procedure based on Genetic Algorithms has been applied. At the end, the error between each obtained dimension and its nominal value has been minimized. The constraints imposed were the maximum values of standard deviations of the dimensions obtained for the final ring.

  2. Spectral signature barcodes based on S-shaped Split Ring Resonators (S-SRRs

    Directory of Open Access Journals (Sweden)

    Herrojo Cristian

    2016-01-01

    Full Text Available In this paper, it is shown that S-shaped split ring resonators (S-SRRs are useful particles for the implementation of spectral signature (i.e., a class of radiofrequency barcodes based on coplanar waveguide (CPW transmission lines loaded with such resonant elements. By virtue of its S shape, these resonators are electrically small. Hence S-SRRs are of interest for the miniaturization of the barcodes, since multiple resonators, each tuned at a different frequency, are used for encoding purposes. In particular, a 10-bit barcode occupying 1 GHz spectral bandwidth centered at 2.5 GHz, with dimensions of 9 cm2, is presented in this paper.

  3. National machine guarding program: Part 1. Machine safeguarding practices in small metal fabrication businesses

    OpenAIRE

    Parker, David L.; Yamin, Samuel C.; Brosseau, Lisa M.; Xi, Min; Gordon, Robert; Most, Ivan G.; Stanley, Rodney

    2015-01-01

    Background Metal fabrication workers experience high rates of traumatic occupational injuries. Machine operators in particular face high risks, often stemming from the absence or improper use of machine safeguarding or the failure to implement lockout procedures. Methods The National Machine Guarding Program (NMGP) was a translational research initiative implemented in conjunction with two workers' compensation insures. Insurance safety consultants trained in machine guarding used standardize...

  4. Fostering resilience in National Guard and Reserve families: A contextual adaptation of an evidence-based parenting program.

    Science.gov (United States)

    Pinna, Keri L M; Hanson, Sheila; Zhang, Na; Gewirtz, Abigail H

    2017-01-01

    Military deployment of a parent is a risk factor for children's internalizing and externalizing problems. This risk may be heightened in National Guard and Reserve (NG/R) families who tend to be isolated from other NG/R families and do not benefit from the centralized support system available to active duty families living on military bases. Isolation and trauma-related disorders may complicate the adjustment of military families during reintegration. An evidence-based parent training intervention was modified to meet the unique needs of recently deployed NG/R parents and their spouses, and the modified program was evaluated in a randomized controlled trial. The current study examines engagement and satisfaction with the program. Modifications such as employment of military-connected facilitators sought to maximize engagement in and satisfaction with the program. Engagement and satisfaction were examined between mothers and fathers, as well as between groups led by a military-connected facilitator and those led by civilian facilitators. Significantly greater engagement was noted for groups that were led by a military-connected facilitator (p = .01). There were no differences between genders in attendance rates, though greater positive group experiences were reported by mothers versus fathers (p = .01). Results are discussed in the context of engagement and satisfaction reported for similar programs. Implications for working with military families are also considered. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  5. Graphene rings in magnetic fields: Aharonov–Bohm effect and valley splitting

    International Nuclear Information System (INIS)

    Wurm, J; Wimmer, M; Richter, K; Baranger, H U

    2010-01-01

    We study the conductance of mesoscopic graphene rings in the presence of a perpendicular magnetic field by means of numerical calculations based on a tight-binding model. First, we consider the magnetoconductance of such rings and observe the Aharonov–Bohm effect. We investigate different regimes of the magnetic flux up to the quantum Hall regime, where the Aharonov–Bohm oscillations are suppressed. Results for both clean (ballistic) and disordered (diffusive) rings are presented. Second, we study rings with smooth mass boundary that are weakly coupled to leads. We show that the valley degeneracy of the eigenstates in closed graphene rings can be lifted by a small magnetic flux, and that this lifting can be observed in the transport properties of the system

  6. Study of n-on-p sensors breakdown in presence of dielectrics placed on top surface

    CERN Document Server

    Helling, Cole Michael; The ATLAS collaboration

    2018-01-01

    The ATLAS Upgrade strip module design has readout flex circuits glued directly on top of the sensors’ active area to facilitate the assembly process and minimize the radiation length. The process requires radiation-hard adhesives compatible with the sensor technology. We report on the studies of the breakdown behavior with miniature versions of the prototype sensors, where candidate adhesives were placed in several locations on top of the sensor, including the strip area, guard ring region, and sensor edge. Thermal cycling tends to attenuate the observed cases of breakdown with glue on top of the guard ring. Glue reaching the sensor edge results in low breakdown voltage if it also covers AC- or DC- pads or bias ring openings. Glue placement on top of guard ring region was performed on a large-format sensor, with generally similar results to the miniature sensor tests, except for a large glue deposition, which resulted in a permanent reduction of the breakdown voltage. Post-irradiation measurements were perf...

  7. Measuring the electron-ion ring parameters by bremsstrahlung

    International Nuclear Information System (INIS)

    Inkin, V.D.; Mozelev, A.A.; Sarantsev, V.P.

    1982-01-01

    A system is described for measuring the number of electrons and ions in the electron-ion rings of a collective heavy ion accelerator. The system operation is based on detecting gamma quanta of bremsstrahlung following the ring electron interaction with the nuclei of neutral atoms and ions at different stages of filling the ring with ions. The radiation detector is a scintillation block - a photomultiplier operating for counting with NaI(Tl) crystal sized 30x30 mm and ensuring the detection efficiency close to unity. The system apparatus is made in the CAMAC standard and rems on-line with the TRA/i miniature computer. The block-diagrams of the system and algorithm of data processing are presented. A conclusion is drawn that the results of measuring the ring parameters with the use of the diagnostics system described are in good agreement within the range of measuring errors with those obtained by means of the diagnostics system employing synchrotron radiation and induction sensors

  8. The natural history of nest defence in a stingless bee, Tetragonisca angustula (Latreille) (Hymenoptera: Apidae), with two distinct types of entrance guards.

    Science.gov (United States)

    Grüter, C; Kärcher, M H; Ratnieks, F L W

    2011-01-01

    The stingless bee Tetragonsica angustula (Latreille) is the only social bee known that has two different types of nest entrance guards. As in other stingless bees and the honey bee one type stands on, in or near the nest entrance. The second type, so far only known in T. angustula, hovers near the nest entrance. In order to gain further understanding of this unique situation we studied guarding behaviour in both types of guards. Using marked bees, we found that individual worker bees guarded for a long time, up to 20 days, relative to their short, average c. 21 day, lifespan. Relatively few, 33%, individually marked guards were seen performing both types of guarding. The others only acted as standing guards. The bees that did perform both types did so over similar periods of their life. Hovering bouts were 57 min long, interrupted by breaks inside the hive of a few minutes (3.3 ± 1.5 min). Standing bouts were slightly longer (74 min) and also interrupted by short breaks (7.82 ± 6.45 min). Human breath, mimicking a vertebrate intruder, caused the guards to retreat into the nest rather than to attack the intruder. Some colonies protected themselves against intruders by closing the entrance during the night (32% and 56% of colonies during two nights). In summary, our results indicate that nest entrance guarding in T. angustula involves division of labour between the two types, in which most guarding individuals only act as standing guards.

  9. Quantum Fourier Transform Over Galois Rings

    OpenAIRE

    Zhang, Yong

    2009-01-01

    Galois rings are regarded as "building blocks" of a finite commutative ring with identity. There have been many papers on classical error correction codes over Galois rings published. As an important warm-up before exploring quantum algorithms and quantum error correction codes over Galois rings, we study the quantum Fourier transform (QFT) over Galois rings and prove it can be efficiently preformed on a quantum computer. The properties of the QFT over Galois rings lead to the quantum algorit...

  10. Special Staff - Joint Staff - Leadership - The National Guard

    Science.gov (United States)

    the ARNG Deputy Director of the ARNG Chief of Staff of the ARNG Command Chief Warrant Officer of the Site Maintenance Battle Focused Training Strategy Battle Staff Training Resources News Publications March Today in Guard History Leadership CNGB VCNGB SEA DANG DARNG Joint Staff J-1 J-2 J-3 J-4 J-5 J-6 J

  11. Nuclear component horizontal seismic restraint

    International Nuclear Information System (INIS)

    Snyder, G.J.

    1988-01-01

    In a nuclear reactor having a reactor vessel, a reactor guard vessel, a thermal insulation shell and a horizontal seismic restraint, a restraint is described comprising: a. a first ring on the wall of the reactor vessel; b. a second ring on the wall of the reactor guard vessel in alignment with the first ring; c. a first block attached to the second ring proximate the first ring so as to provide a predetermined clearance between the first block and the first ring which is reduced to zero during thermal expansion; d. motion limit means extending through an aperture in the thermal insulation shell in alignment with the second ring and the first block; the e. a second block attached to the motion limit means proximate the second ring and in alignment the first block so as to provide a predetermined clearance between the second block and the second ring which is reduced to zero during thermal expansion

  12. Novel microwave photonic fractional hilbert transformer using a ring resonator-based optical all-pass filter

    NARCIS (Netherlands)

    Zhuang, L.; Khan, M.R.H.; Beeker, Willem; Beeker, W.P.; Leinse, Arne; Heideman, Rene; Roeloffzen, C.G.H.

    2012-01-01

    We propose and demonstrate a novel wideband microwave photonic fractional Hilbert transformer implemented using a ring resonatorbased optical all-pass filter. The full programmability of the ring resonator allows variable and arbitrary fractional order of the Hilbert transformer. The performance

  13. Novel manifestations of the Aharonov-Bohm effect in quantum rings and Moebius rings

    International Nuclear Information System (INIS)

    Fomin, Vladimir M.

    2013-01-01

    - An overview is given on the recent experimental and theoretical advancements in studies of novel manifestations of the Aharonov-Bohm quantum-interference effect for excitons confined to self assembled quantum rings and other semiconductor nanostructures with ring-like states of charge carriers as well as for electrons in Moebius rings at the micro- and nanoscale. The exciton Aharonov-Bohm effect can be effectively controlled by an out-of-plane magnetic field, a vertical electric field, a spin disorder. A 'delocalization-to-localization' transition for the electron ground state occurs in a Moebius ring as it is made more inhomogeneous. (authors)

  14. Ring closure in actin polymers

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, Supurna, E-mail: supurna@rri.res.in [Raman Research Institute, Bangalore 560080 (India); Chattopadhyay, Sebanti [Doon University, Dehradun 248001 (India)

    2017-03-18

    We present an analysis for the ring closure probability of semiflexible polymers within the pure bend Worm Like Chain (WLC) model. The ring closure probability predicted from our analysis can be tested against fluorescent actin cyclization experiments. We also discuss the effect of ring closure on bend angle fluctuations in actin polymers. - Highlights: • Ring closure of biopolymers. • Worm like chain model. • Predictions for experiments.

  15. On P-coherent endomorphism rings

    Indian Academy of Sciences (India)

    A ring is called right -coherent if every principal right ideal is finitely presented. Let M R be a right -module. We study the -coherence of the endomorphism ring of M R . It is shown that is a right -coherent ring if and only if every endomorphism of M R has a pseudokernel in add M R ; S is a left -coherent ring if and ...

  16. Improved Coast Guard Communications Using Commercial Satellites and WWW Technology

    Science.gov (United States)

    1997-06-18

    Information collection and distribution are essential components of most Coast Guard missions. However, information needs have typically outpaced the ability of the installed communications systems to meet those needs. This mismatch leads to reduced ...

  17. Faithfully quadratic rings

    CERN Document Server

    Dickmann, M

    2015-01-01

    In this monograph the authors extend the classical algebraic theory of quadratic forms over fields to diagonal quadratic forms with invertible entries over broad classes of commutative, unitary rings where -1 is not a sum of squares and 2 is invertible. They accomplish this by: (1) Extending the classical notion of matrix isometry of forms to a suitable notion of T-isometry, where T is a preorder of the given ring, A, or T = A^2. (2) Introducing in this context three axioms expressing simple properties of (value) representation of elements of the ring by quadratic forms, well-known to hold in

  18. Tree-ring proxies of larch bud moth defoliation: latewood width and blue intensity are more precise than tree-ring width.

    Science.gov (United States)

    Arbellay, Estelle; Jarvis, Ingrid; Chavardès, Raphaël D; Daniels, Lori D; Stoffel, Markus

    2018-05-19

    Reconstructions of defoliation by larch bud moth (LBM, Zeiraphera diniana Gn.) based on European larch (Larix decidua Mill.) tree rings have unraveled outbreak patterns over exceptional temporal and spatial scales. In this study, we conducted tree-ring analyses on 105 increment cores of European larch from the Valais Alps, Switzerland. The well-documented history of LBM outbreaks in Valais provided a solid baseline for evaluating the LBM defoliation signal in multiple tree-ring parameters. First, we used tree-ring width measurements along with regional records of LBM outbreaks to reconstruct the occurrence of these events at two sites within the Swiss Alps. Second, we measured earlywood width, latewood width and blue intensity, and compared these parameters with tree-ring width to assess the capacity of each proxy to detect LBM defoliation. A total of six LBM outbreaks were reconstructed for the two sites between AD 1850 and 2000. Growth suppression induced by LBM was, on average, highest in latewood width (59%), followed by total ring width (54%), earlywood width (51%) and blue intensity (26%). We show that latewood width and blue intensity can improve the temporal accuracy of LBM outbreak reconstructions, as both proxies systematically detected LBM defoliation in the first year it occurred, as well as the differentiation between defoliation and non-defoliation years. This study introduces blue intensity as a promising new proxy of insect defoliation and encourages its use in conjunction with latewood width.

  19. BERKELEY: ALS ring

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1993-06-15

    Everybody at Lawrence Berkeley Laboratory's Center for Beam Physics is pleased with the rapid progress in commissioning LBL's Advanced Light Source (ALS) electron storage ring, the foundation for this third-generation synchrotron radiation facility. Designed for a maximum current of 400 mA, the ALS storage ring reached 407 mA just 24 days after storing the first beam on 16 March. ALS construction as a US Department of Energy (DOE) national user facility to provide high-brightness vacuum ultra-violet and soft x-ray radiation began in October 1987. One technical requirement marking project completion was to accumulate a 50-mA current in the storage ring. The ALS passed this milestone on 24 March, a week ahead of the official deadline. Once injected, the electron beam decays quasi-exponentially primarily because of interactions with residual gas molecules in the storage-ring vacuum chamber. Eventually, when the pressure in the vacuum chamber with beam decreases toward the expected operating level of 1 nano Torr, it will only be necessary to refill the storage ring at intervals of four to eight hours. At present the vacuum is improving rapidly as surfaces are irradiated (scrubbed) by the synchrotron radiation itself. At 100 mA, beam lifetime was about one hour (9 April)

  20. Compressible Vortex Ring

    Science.gov (United States)

    Elavarasan, Ramasamy; Arakeri, Jayawant; Krothapalli, Anjaneyulu

    1999-11-01

    The interaction of a high-speed vortex ring with a shock wave is one of the fundamental issues as it is a source of sound in supersonic jets. The complex flow field induced by the vortex alters the propagation of the shock wave greatly. In order to understand the process, a compressible vortex ring is studied in detail using Particle Image Velocimetry (PIV) and shadowgraphic techniques. The high-speed vortex ring is generated from a shock tube and the shock wave, which precedes the vortex, is reflected back by a plate and made to interact with the vortex. The shadowgraph images indicate that the reflected shock front is influenced by the non-uniform flow induced by the vortex and is decelerated while passing through the vortex. It appears that after the interaction the shock is "split" into two. The PIV measurements provided clear picture about the evolution of the vortex at different time interval. The centerline velocity traces show the maximum velocity to be around 350 m/s. The velocity field, unlike in incompressible rings, contains contributions from both the shock and the vortex ring. The velocity distribution across the vortex core, core diameter and circulation are also calculated from the PIV data.

  1. BERKELEY: ALS ring

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Everybody at Lawrence Berkeley Laboratory's Center for Beam Physics is pleased with the rapid progress in commissioning LBL's Advanced Light Source (ALS) electron storage ring, the foundation for this third-generation synchrotron radiation facility. Designed for a maximum current of 400 mA, the ALS storage ring reached 407 mA just 24 days after storing the first beam on 16 March. ALS construction as a US Department of Energy (DOE) national user facility to provide high-brightness vacuum ultra-violet and soft x-ray radiation began in October 1987. One technical requirement marking project completion was to accumulate a 50-mA current in the storage ring. The ALS passed this milestone on 24 March, a week ahead of the official deadline. Once injected, the electron beam decays quasi-exponentially primarily because of interactions with residual gas molecules in the storage-ring vacuum chamber. Eventually, when the pressure in the vacuum chamber with beam decreases toward the expected operating level of 1 nano Torr, it will only be necessary to refill the storage ring at intervals of four to eight hours. At present the vacuum is improving rapidly as surfaces are irradiated (scrubbed) by the synchrotron radiation itself. At 100 mA, beam lifetime was about one hour (9 April)

  2. Accidental ingestion of BiTine ring and a note on inefficient ring separation forceps

    Directory of Open Access Journals (Sweden)

    Baghele ON

    2011-05-01

    Full Text Available Om Nemichand Baghele1, Mangala Om Baghele21Department of Periodontology, SMBT Dental College and Hospital, Sangamner, Ahmednagar, Maharashtra, India; 2Private General Dental Practice, Mumbai, IndiaBackground: Accidental ingestion of medium-to-large instruments is relatively uncommon during dental treatment but can be potentially dangerous. A case of BiTine ring ingestion is presented with a note on inefficient ring separation forceps.Case description: A 28-year-old male patient accidentally ingested the BiTine ring (2 cm diameter, 0.5 cm outward projections while it was being applied to a distoproximal cavity in tooth # 19. The ring placement forceps were excessively flexible; bending of the beaks towards the ring combined with a poor no-slippage mechanism led to sudden disengagement of the ring and accelerated movement towards the pharynx. We followed the patient with bulk forming agents and radiographs. Fortunately the ring passed out without any complications.Clinical implications: Checking equipment and methods is as important as taking precautions against any preventable medical emergency. It is the responsibility of the clinician to check, verify and then use any instrument/equipment.Keywords: foreign bodies/radiography, foreign bodies/complications, equipment failure, dental instrument, accidental ingestion

  3. On the Laurent polynomial rings

    International Nuclear Information System (INIS)

    Stefanescu, D.

    1985-02-01

    We describe some properties of the Laurent polynomial rings in a finite number of indeterminates over a commutative unitary ring. We study some subrings of the Laurent polynomial rings. We finally obtain two cancellation properties. (author)

  4. A metric model of lambda calculus with guarded recursion

    DEFF Research Database (Denmark)

    Birkedal, Lars; Schwinghammer, Jan; Støvring, Kristian

    2010-01-01

    We give a model for Nakano’s typed lambda calculus with guarded recursive definitions in a category of metric spaces. By proving a computational adequacy result that relates the interpretation with the operational semantics, we show that the model can be used to reason about contextual equivalence....

  5. 77 FR 31183 - Safety Zone, Temporary Change for Recurring Fireworks Display Within the Fifth Coast Guard...

    Science.gov (United States)

    2012-05-25

    ...-AA00 Safety Zone, Temporary Change for Recurring Fireworks Display Within the Fifth Coast Guard District, Pamlico River and Tar River; Washington, NC AGENCY: Coast Guard, DHS. ACTION: Temporary final... is intended to restrict vessel traffic in a portion of the Pamlico River and Tar River near...

  6. EBT ring physics

    International Nuclear Information System (INIS)

    Uckan, N.A.

    1980-04-01

    This workshop attempted to evaluate the status of the current experimental and theoretical understanding of hot electron ring properties. The dominant physical processes that influence ring formation, scaling, and their optimal behavior are also studied. Separate abstracts were prepared for each of the 27 included papers

  7. Receiver sensitivity improvement in spectrally-efficient guard-band twin-SSB-OFDM using an optical IQ modulator

    Science.gov (United States)

    Chen, Ming; Peng, Miao; Zhou, Hui; Zheng, Zhiwei; Tang, Xionggui; Maivan, Lap

    2017-12-01

    To further improve receiver sensitivity of spectrally-efficient guard-band direct-detection optical orthogonal frequency-division multiplexing (OFDM) with twin single-side-band (SSB) modulation technique, an optical IQ modulator (IQM) is employed to optimize optical carrier-to-signal power ratio (CSPR). The CSPRs for the guard-band twin-SSB-OFDM signal generated by using dual-drive Mach-Zehnder modulator (DD-MZM) and optical IQM are theoretically analyzed and supported by simulations. The optimal CSPR for the two types of guard-band twin-SSB-OFDM are identified. The simulations exhibit that the error vector magnitude (EVM) performance of the IQM-enabled guard-band twin-SSB-OFDM is improved by more than 4-dB compared to that of the twin-SSB-OFDM enabled by DD-MZM after 80-km single-mode fiber (SMF) transmission. In addition, more than 3-dB and 10 dB receiver sensitivity improvements in terms of received optical power (ROP) and optical signal-to-noise ratio (OSNR) are also achieved, respectively.

  8. Ground Movement in SSRL Ring

    International Nuclear Information System (INIS)

    Sunikumar, Nikita

    2011-01-01

    Users of the Stanford Synchrotron Radiation Lightsource (SSRL) are being affected by diurnal motion of the synchrotron's storage ring, which undergoes structural changes due to outdoor temperature fluctuations. In order to minimize the effects of diurnal temperature fluctuations, especially on the vertical motion of the ring floor, scientists at SSRL tried three approaches: painting the storage ring white, covering the asphalt in the middle of the ring with highly reflective Mylar and installing Mylar on a portion of the ring roof and walls. Vertical motion in the storage ring is measured by a Hydrostatic Leveling System (HLS), which calculates the relative height of water in a pipe that extends around the ring. The 24-hr amplitude of the floor motion was determined using spectral analysis of HLS data, and the ratio of this amplitude before and after each experiment was used to quantitatively determine the efficacy of each approach. The results of this analysis showed that the Mylar did not have any significant effect on floor motion, although the whitewash project did yield a reduction in overall HLS variation of 15 percent. However, further analysis showed that the reduction can largely be attributed to a few local changes rather than an overall reduction in floor motion around the ring. Future work will consist of identifying and selectively insulating these local regions in order to find the driving force behind diurnal floor motion in the storage ring.

  9. The role of oxytocin and vasopressin in conditioned mate guarding behavior in the female rat.

    Science.gov (United States)

    Holley, Amanda; Bellevue, Shannon; Vosberg, Daniel; Wenzel, Kerstin; Roorda, Sieger; Pfaus, James G

    2015-05-15

    We have shown previously that female rats given their first copulatory experiences with the same male rat display mate guarding behavior in the presence of that male provided a female competitor is also present. Females given access to the familiar male show more Fos induction within regions of the brain that contain oxytocin (OT) and vasopressin (AVP) cell bodies, notably the supraoptic (SON) and paraventricular nuclei (PVN) relative to females given sexual experience with different males. The present experiments examined whether the Fos induction we previously observed within the SON and PVN occurred within OT and/or AVP neurons, and whether exogenous administration of OT or AVP prior to female rats first sexual experience could potentiate the acquisition of mate guarding behavior. Female rats that display conditioned mate guarding had significantly more double-labeled Fos/OT neurons in both SON and PVN, and significantly more Fos/AVP neurons in the PVN. Peripheral administration of OT or AVP prior to their first sexual experience with the familiar male facilitated different aspects of mate guarding: OT augmented affiliative behaviors and presenting responses whereas AVP augmented interference behavior. These results indicate that female rats' first experiences with sexual reward when paired with the same male induce changes to bonding networks in the brain. Moreover peripheral administration of OT or AVP during their first sexual experience can augment different aspects of mate guarding behavior. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Eliminate the Army and Air Force Reserves: Building a Robust National Guard to Meet 21st Century Operational Challenges

    Science.gov (United States)

    2016-04-04

    TITLE AND SUBTITLE ELIMINATE THE ARMY AND AIR FORCE RESERVES: BUILDING A ROBUST NATIONAL GUARD TO MEET 21ST CENTURY OPERATIONAL CHALLENGES 5a...STAFF COLLEGE JOINT ADVANCED WARFIGHTING SCHOOL ELIMINATE THE ARMY AND AIR FORCE RESERVES: BUILDING A ROBUST NATIONAL GUARD TO... ELIMINATE THE ARMY AND AIR FORCE RESERVES: BUILDING A ROBUST NATIONAL GUARD TO MEET 21ST CENTURY OPERATIONAL CHALLENGES by

  11. Comparing CTH simulations and experiments on explosively loaded rings

    Science.gov (United States)

    Braithwaite, C. H.; Aydelotte, Brady; Collins, Adam; Thadhani, Naresh; Williamson, David Martin

    2012-03-01

    A series of experiments were conducted on explosively loaded metallic rings for the purpose of studying fragmentation. In addition to the collection of fragments for analysis, the radial velocity of the expanding ring was measured with photon Doppler velocimetry (PDV) and the arrangement was imaged using high speed photography. Both the ring material and the material used as the explosive container were altered and the results compared with simulations performed in CTH. Good agreement was found between the simulations and the experiments. The maximum radial velocity attained was approximately 380 m/s, which was achieved through loading with a 5g PETN based charge.

  12. 76 FR 66933 - Privacy Act of 1974; Department of Homeland Security U.S. Coast Guard DHS/USCG-014 Military Pay...

    Science.gov (United States)

    2011-10-28

    ... 1974; Department of Homeland Security U.S. Coast Guard DHS/USCG--014 Military Pay and Personnel System... Security U.S. Coast Guard--014 Military Pay and Personnel System of Records.'' This system of records allows the Department of Homeland Security U.S. Coast Guard to collect and maintain records regarding pay...

  13. Token ring technology report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. This report provides an overview of the IBM Token-Ring technology and products built by IBM and compatible vendors. It consists of two sections: 1. A summary of the design trade-offs for the IBM Token-Ring. 2. A summary of the products of the major token-ring compatible vendors broken down by adapters and components, wiring systems, testing, and new chip technology.

  14. Novel ring resonator-based integrated photonic beamformer for broadband phased array receive antennas - part 1: design and performance analysis

    NARCIS (Netherlands)

    Meijerink, Arjan; Roeloffzen, C.G.H.; Meijerink, Roland; Zhuang, L.; Marpaung, D.A.I.; Bentum, Marinus Jan; Burla, M.; Verpoorte, Jaco; Jorna, Pieter; Huizinga, Adriaan; van Etten, Wim

    2010-01-01

    A novel optical beamformer concept is introduced that can be used for seamless control of the reception angle in broadband wireless receivers employing a large phased array antenna (PAA). The core of this beamformer is an optical beamforming network (OBFN), using ring resonator-based broadband

  15. Expression of Arabidopsis hexokinase in citrus guard cells controls stomatal aperture and reduces transpiration

    Directory of Open Access Journals (Sweden)

    Nitsan eLugassi

    2015-12-01

    Full Text Available Hexokinase (HXK is a sugar-phosphorylating enzyme involved in sugar-sensing. It has recently been shown that HXK in guard cells mediates stomatal closure and coordinates photosynthesis with transpiration in the annual species tomato and Arabidopsis. To examine the role of HXK in the control of the stomatal movement of perennial plants, we generated citrus plants that express Arabidopsis HXK1 (AtHXK1 under KST1, a guard cell-specific promoter. The expression of KST1 in the guard cells of citrus plants has been verified using GFP as a reporter gene. The expression of AtHXK1 in the guard cells of citrus reduced stomatal conductance and transpiration with no negative effect on the rate of photosynthesis, leading to increased water-use efficiency. The effects of light intensity and humidity on stomatal behavior were examined in rooted leaves of the citrus plants. The optimal intensity of photosynthetically active radiation and lower humidity enhanced stomatal closure of AtHXK1-expressing leaves, supporting the role of sugar in the regulation of citrus stomata. These results suggest that HXK coordinates photosynthesis and transpiration and stimulates stomatal closure not only in annual species, but also in perennial species.

  16. Ring-enhancing spinal cord lesions in neuromyelitis optica spectrum disorders.

    Science.gov (United States)

    Zalewski, Nicholas L; Morris, Padraig P; Weinshenker, Brian G; Lucchinetti, Claudia F; Guo, Yong; Pittock, Sean J; Krecke, Karl N; Kaufmann, Timothy J; Wingerchuk, Dean M; Kumar, Neeraj; Flanagan, Eoin P

    2017-03-01

    We assessed the frequency and characteristics of ring-enhancing spinal cord lesions in neuromyelitis optica spectrum disorder (NMOSD) myelitis and myelitis of other cause. We reviewed spinal cord MRIs for ring-enhancing lesions from 284 aquaporin-4 (AQP4)-IgG seropositive patients at Mayo Clinic from 1996 to 2014. Inclusion criteria were as follows: (1) AQP4-IgG seropositivity, (2) myelitis attack and (3) MRI spinal cord demonstrating ring-enhancement. We identified two groups of control patients with: (1) longitudinally extensive myelopathy of other cause (n=66) and (2) myelitis in the context of a concurrent or subsequent diagnosis of multiple sclerosis (MS) from a population-based cohort (n=30). Ring-enhancement was detected in 50 of 156 (32%) myelitis episodes in 41 patients (83% single; 17% multiple attacks). Ring-enhancement was noted on sagittal and axial images in 36 of 43 (84%) ring enhancing myelitis episodes and extended a median of two vertebral segments (range, 1-12); in 21 of 48 (44%) ring enhancing myelitis episodes, the ring extended greater than or equal to three vertebrae. Ring-enhancement was accompanied by longitudinally extensive (greater than or equal to three vertebral segments) T2-hyperintensity in 44 of 50 (88%) ring enhancing myelitis episodes. One case of a spinal cord biopsy during ring-enhancing myelitis revealed tissue vacuolation and loss of AQP4 immunoreactivity with preserved axons. The clinical characteristics of ring-enhancing myelitis episodes did not differ from non-ring-enhancing episodes. Ring-enhancing spinal cord lesions were more common in NMOSD than other causes of longitudinally extensive myelopathy (50/156 (32%) vs 0/66 (0%); p≤0.001) but did not differ between NMOSD and MS (50/156 (32%) vs 6/30 (20%); p=0.20). Spinal cord ring-enhancement accompanies one-third of NMOSD myelitis episodes and distinguishes NMOSD from other causes of longitudinally extensive myelopathies but not from MS. Published by the BMJ Publishing

  17. Prototype moving-ring reactor

    International Nuclear Information System (INIS)

    Smith, A.C. Jr.; Ashworth, C.P.; Abreu, K.E.

    1982-01-01

    We have completed a design of the Prototype Moving-Ring Reactor. The fusion fuel is confined in current-carrying rings of magnetically-field-reversed plasma (Compact Toroids). The plasma rings, formed by a coaxial plasma gun, undergo adiabatic magnetic compression to ignition temperature while they are being injected into the reactor's burner section. The cylindrical burner chamber is divided into three burn stations. Separator coils and a slight axial guide field gradient are used to shuttle the ignited toroids rapidly from one burn station to the next, pausing for 1/3 of the total burn time at each station. D-T- 3 He ice pellets refuel the rings at a rate which maintains constant radiated power

  18. Polycomb Group Proteins RING1A and RING1B Regulate the Vegetative Phase Transition in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Jian Li

    2017-05-01

    Full Text Available Polycomb group (PcG protein-mediated gene silencing is a major regulatory mechanism in higher eukaryotes that affects gene expression at the transcriptional level. Here, we report that two conserved homologous PcG proteins, RING1A and RING1B (RING1A/B, are required for global H2A monoubiquitination (H2Aub in Arabidopsis. The mutation of RING1A/B increased the expression of members of the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL gene family and caused an early vegetative phase transition. The early vegetative phase transition observed in ring1a ring1b double mutant plants was dependent on an SPL family gene, and the H2Aub status of the chromatin at SPL locus was dependent on RING1A/B. Moreover, mutation in RING1A/B affected the miRNA156a-mediated vegetative phase transition, and RING1A/B and the AGO7-miR390-TAS3 pathway were found to additively regulate this transition in Arabidopsis. Together, our results demonstrate that RING1A/B regulates the vegetative phase transition in Arabidopsis through the repression of SPL family genes.

  19. Researches on the Piston Ring

    Science.gov (United States)

    Ehihara, Keikiti

    1944-01-01

    In internal combustion engines, steam engines, air compressors, and so forth, the piston ring plays an important role. Especially, the recent development of Diesel engines which require a high compression pressure for their working, makes, nowadays, the packing action of the piston ring far more important than ever. Though a number of papers have been published in regard to researches on the problem of the piston ring, none has yet dealt with an exact measurement of pressure exerted on the cylinder wall at any given point of the ring. The only paper that can be traced on this subject so far is Mr. Nakagawa's report on the determination of the relative distribution of pressure on the cylinder wall, but the measuring method adopted therein appears to need further consideration. No exact idea has yet been obtained as to how the obturation of gas between the piston and cylinder, the frictional resistance of the piston, and the wear of the cylinder wall are affected by the intensity and the distribution of the radial pressure of the piston ring. Consequently, the author has endeavored, by employing an apparatus of his own invention, to get an exact determination of the pressure distribution of the piston ring. By means of a newly devised ring tester, to which piezoelectricity of quartz was applied, the distribution of the radial pressure of many sample rings on the market was accurately determined. Since many famous piston rings show very irregular pressure distribution, the author investigated and achieved a manufacturing process of the piston ring which will exert uniform pressure on the cylinder wall. Temperature effects on the configuration and on the mean spring power have also been studied. Further, the tests were performed to ascertain how the gas tightness of the piston ring may be affected by the number or spring power. The researches as to the frictional resistance between the piston ring and the cylinder wall were carried out, too. The procedure of study, and

  20. Optimization and Simulation of Machining Parameters in Radial-axial Ring Rolling Process

    Directory of Open Access Journals (Sweden)

    Shuiyuan Tang

    2011-05-01

    Full Text Available Ring rolling is a complicated process, in which rolling parameters influence directly the quality of ring. It is a process method with high productivity and few waste of material, widely used in transportation industry including automotive, shipbuilding, aerospace etc. During the rolling process of large-sized parts, crinkle and hollows often appear on surface, due to inconsistence of rolling motions with the deformation of ring part. Based on radial-axial ring rolling system configuration, motions and forces in rolling process are analyzed, and a dynamic model is formulated. Error of ring's end flatness and roundness are defined as the characteristic parameters of ring quality. The relationship between core roller feed speed, drive roller speed, the upper taper roller feed speed, and quality of ring part are analyzed. The stress and strain of the part are simulated in the Finite Element Method by DEFORM software. The simulation results provide a reference for the definition of ring rolling process parameters. It is able to make the deformation of the part be consistent with the process parameters, and improve product quality considerably.