Unity power factor converter

NASA Technical Reports Server (NTRS)

Wester, Gene W. (Inventor)

1980-01-01

A unity power factor converter capable of effecting either inversion (dc-to-dc) or rectification (ac-to-dc), and capable of providing bilateral power control from a DC source (or load) through an AC transmission line to a DC load (or source) for power flow in either direction, is comprised of comparators for comparing the AC current i with an AC signal i.sub.ref (or its phase inversion) derived from the AC ports to generate control signals to operate a switch control circuit for high speed switching to shape the AC current waveform to a sine waveform, and synchronize it in phase and frequency with the AC voltage at the AC ports, by selectively switching the connections to a series inductor as required to increase or decrease the current i.

Control circuit maintains unity power factor of reactive load

NASA Technical Reports Server (NTRS)

Kramer, M.; Martinage, L. H.

1966-01-01

Circuit including feedback control elements automatically corrects the power factor of a reactive load. It maintains power supply efficiency where negative load reactance changes and varies by providing corrective error signals to the control windings of a power supply transformer.

Sturckow in the Node 1/Unity module

NASA Image and Video Library

1999-01-11

STS088-359-003 (4-15 Dec. 1998) --- Astronaut Frederick W. ?Rick? Sturckow, pilot, holds up a panel while putting final touches on the interior of Node 1 or Unity. Sturckow, who had been working with a battery-powered tool, was joined by other crew members in preparing the module for its International Space Station (ISS) duty.

A Comparative Study on the Practice of Continuous Assessment between Addis Ababa and Unity Universities

ERIC Educational Resources Information Center

Zeleke, Aytaged Sisay

2013-01-01

This paper aims to explore the practice of continuous assessment at Unity University College and Addis Ababa University. It has also investigated constraints instructors say they have been facing in implementing continuous assessment. Students' attitudes about the practice of this assessment mode towards their course achievements were explored.…

On Narrative Method, Biography and Narrative Unities in the Study of Teaching.

ERIC Educational Resources Information Center

Connelly, F. Michael; Clandinin, D. Jean

This paper outlines a narrative method for the study of teaching which has as its principle feature the reconstruction of classroom meaning in terms of narrative unities in the lives of classroom participants. This purpose is achieved by comparatively outlining similarities and differences with closely associated lines of work. This study of…

Near-Unity Absorption in van der Waals Semiconductors for Ultrathin Optoelectronics.

PubMed

Jariwala, Deep; Davoyan, Artur R; Tagliabue, Giulia; Sherrott, Michelle C; Wong, Joeson; Atwater, Harry A

2016-09-14

We demonstrate near-unity, broadband absorbing optoelectronic devices using sub-15 nm thick transition metal dichalcogenides (TMDCs) of molybdenum and tungsten as van der Waals semiconductor active layers. Specifically, we report that near-unity light absorption is possible in extremely thin (<15 nm) van der Waals semiconductor structures by coupling to strongly damped optical modes of semiconductor/metal heterostructures. We further fabricate Schottky junction devices using these highly absorbing heterostructures and characterize their optoelectronic performance. Our work addresses one of the key criteria to enable TMDCs as potential candidates to achieve high optoelectronic efficiency.

Method for obtaining a collimated near-unity aspect ratio output beam from a DFB-GSE laser with good beam quality.

PubMed

Liew, S K; Carlson, N W

1992-05-20

A simple method for obtaining a collimated near-unity aspect ratio output beam from laser sources with extremely large (> 100:1) aspect ratios is demonstrated by using a distributed-feedback grating-surfaceemitting laser. Far-field power-in-the-bucket measurements of the laser indicate good beam quality with a high Strehl ratio.

How culture shapes community: bible belief, theological unity, and a sense of belonging in religious congregations.

PubMed

Stroope, Samuel

2011-01-01

Feeling that you belong in a group is an important and powerful need. The ability to foster a sense of belonging can also determine whether groups survive. Organizational features of groups cultivate feelings of belonging, yet prior research fails to investigate the idea that belief systems also play a major role. Using multilevel data, this study finds that church members' traditional beliefs, group-level belief unity, and their interaction associate positively with members' sense of belonging. In fact, belief unity can be thought of as a “sacred canopy” under which the relationship between traditional beliefs and feelings of belonging thrives.

Vibration energy harvesting using piezoelectric unimorph cantilevers with unequal piezoelectric and nonpiezoelectric lengths

PubMed Central

Gao, Xiaotong; Shih, Wei-Heng; Shih, Wan Y.

2010-01-01

We have examined a piezoelectric unimorph cantilever (PUC) with unequal piezoelectric and nonpiezoelectric lengths for vibration energy harvesting theoretically by extending the analysis of a PUC with equal piezoelectric and nonpiezoelectric lengths. The theoretical approach was validated by experiments. A case study showed that for a fixed vibration frequency, the maximum open-circuit induced voltage which was important for charge storage for later use occurred with a PUC that had a nonpiezoelectric-to-piezoelectric length ratio greater than unity, whereas the maximum power when the PUC was connected to a resistor for immediate power consumption occurred at a unity nonpiezoelectric-to-piezoelectric length ratio. PMID:21200444

Ripple feedback for the resonant-filter unity-power-factor rectifier

DOE Office of Scientific and Technical Information (OSTI.GOV)

Streng, S.A.; King, R.J.

1992-07-01

An unusual bucklike unity-power-factor rectifier with a resonant load-balancing network permits current-limited operation down to zero output voltage in a single-stage-topology. However, this rectifier has been found to be sensitive to ac-line voltage distortion and is potentially unstable with realistic values of ac-line impedance. In this paper, a new ripple feedback is proposed that solves both problems. A large-signal time-varying analysis is given along with incremental, quasi-static, and low-frequency approximations. Experimental verification is provided by a 500-W 50-kHz rectifier operating from the 120-V 60-Hz distribution system.

Vibration energy harvesting using piezoelectric unimorph cantilevers with unequal piezoelectric and nonpiezoelectric lengths.

PubMed

Gao, Xiaotong; Shih, Wei-Heng; Shih, Wan Y

2010-12-06

We have examined a piezoelectric unimorph cantilever (PUC) with unequal piezoelectric and nonpiezoelectric lengths for vibration energy harvesting theoretically by extending the analysis of a PUC with equal piezoelectric and nonpiezoelectric lengths. The theoretical approach was validated by experiments. A case study showed that for a fixed vibration frequency, the maximum open-circuit induced voltage which was important for charge storage for later use occurred with a PUC that had a nonpiezoelectric-to-piezoelectric length ratio greater than unity, whereas the maximum power when the PUC was connected to a resistor for immediate power consumption occurred at a unity nonpiezoelectric-to-piezoelectric length ratio.

Fuel gain exceeding unity in an inertially confined fusion implosion.

PubMed

Hurricane, O A; Callahan, D A; Casey, D T; Celliers, P M; Cerjan, C; Dewald, E L; Dittrich, T R; Döppner, T; Hinkel, D E; Berzak Hopkins, L F; Kline, J L; Le Pape, S; Ma, T; MacPhee, A G; Milovich, J L; Pak, A; Park, H-S; Patel, P K; Remington, B A; Salmonson, J D; Springer, P T; Tommasini, R

2014-02-20

Ignition is needed to make fusion energy a viable alternative energy source, but has yet to be achieved. A key step on the way to ignition is to have the energy generated through fusion reactions in an inertially confined fusion plasma exceed the amount of energy deposited into the deuterium-tritium fusion fuel and hotspot during the implosion process, resulting in a fuel gain greater than unity. Here we report the achievement of fusion fuel gains exceeding unity on the US National Ignition Facility using a 'high-foot' implosion method, which is a manipulation of the laser pulse shape in a way that reduces instability in the implosion. These experiments show an order-of-magnitude improvement in yield performance over past deuterium-tritium implosion experiments. We also see a significant contribution to the yield from α-particle self-heating and evidence for the 'bootstrapping' required to accelerate the deuterium-tritium fusion burn to eventually 'run away' and ignite.

United States Counterinsurgency Theory

DTIC Science & Technology

2010-04-01

energies should be directed.‖ 34 The DoD Dictionary defines a COG as the source of power that provides moral or physical strength, freedom of action...planners to determine the physical or geographic points, key events, functions, and systems that will provide unity of effort and unity of action during a...medical, and education; governance or arbitration; and expression or self- actualization of religion or political expression. The absence of physical

2D and 3D virtual interactive laboratories of physics on Unity platform

NASA Astrophysics Data System (ADS)

González, J. D.; Escobar, J. H.; Sánchez, H.; De la Hoz, J.; Beltrán, J. R.

2017-12-01

Using the cross-platform game engine Unity, we develop virtual laboratories for PC, consoles, mobile devices and website as an innovative tool to study physics. There is extensive uptake of ICT in the teaching of science and its impact on the learning, and considering the limited availability of laboratories for physics teaching and the difficulties this causes in the learning of school students, we design the virtual laboratories to enhance studentâĂŹs knowledge of concepts in physics. To achieve this goal, we use Unity due to provide support bump mapping, reflection mapping, parallax mapping, dynamics shadows using shadows maps, full-screen post-processing effects and render-to-texture. Unity can use the best variant for the current video hardware and, if none are compatible, to use an alternative shader that may sacrifice features for performance. The control over delivery to mobile devices, web browsers, consoles and desktops is the main reason Unity is the best option among the same kind cross-platform. Supported platforms include Android, Apple TV, Linux, iOS, Nintendo 3DS line, macOS, PlayStation 4, Windows Phone 8, Wii but also an asset server and Nvidia’s PhysX physics engine which is the most relevant tool on Unity for our PhysLab.

Phillips removes Failed RPCM (Remote Power Controller Module)

NASA Image and Video Library

2005-09-20

ISS011-E-13361 (20 September 2005) --- Astronaut John L. Phillips, Expedition 11 NASA science officer and flight engineer, performs a Remote Power Control Module (RPCM) remove and replacement in the Unity node of the international space station.

Unity Power Factor Operated PFC Converter Based Power Supply for Computers

NASA Astrophysics Data System (ADS)

Singh, Shikha; Singh, Bhim; Bhuvaneswari, G.; Bist, Vashist

2017-11-01

Power Supplies (PSs) employed in personal computers pollute the single phase ac mains by drawing distorted current at a substandard Power Factor (PF). The harmonic distortion of the supply current in these personal computers are observed 75% to 90% with the Crest Factor (CF) being very high which escalates losses in the distribution system. To find a tangible solution to these issues, a non-isolated PFC converter is employed at the input of isolated converter that is capable of improving the input power quality apart from regulating the dc voltage at its output. This is given to the isolated stage that yields completely isolated and stiffly regulated multiple output voltages which is the prime requirement of computer PS. The operation of the proposed PS is evaluated under various operating conditions and the results show improved performance depicting nearly unity PF and low input current harmonics. The prototype of this PS is developed in laboratory environment and test results are recorded which corroborate the power quality improvement observed in simulation results under various operating conditions.

KSC-98pc1219

NASA Image and Video Library

1998-10-03

KENNEDY SPACE CENTER, FLA. -- Lowered on a movable work platform or bucket inside the payload bay of orbiter Endeavour, STS-88 Mission Specialists Jerry L. Ross (far right) and James H. Newman (second from right) get a close look at the Orbiter Docking System. At left is the bucket operator and Wayne Wedlake, with United Space Alliance at Johnson Space Center. The STS-88 crew members are in Orbiter Processing Facility Bay 1 to participate in a Crew Equipment Interface Test (CEIT) to familiarize themselves with the orbiter's midbody and crew compartments. Targeted for liftoff on Dec. 3, 1998, STS-88 will be the first Space Shuttle launch for assembly of the International Space Station (ISS). The primary payload is the Unity connecting module which will be mated to the Russian-built Zarya control module, expected to be already on orbit after a November launch from Russia. While on orbit during STS-88, Unity will be latched atop the Orbiter Docking System in the forward section of Endeavour's payload bay for the mating of the two modules. After the mating, Ross and Newman are scheduled to perform three spacewalks to connect power, data and utility lines and install exterior equipment. The first major U.S.-built component of ISS, Unity will serve as a connecting passageway to living and working areas of the space station. Unity has two attached pressurized mating adapters (PMAs) and one stowage rack installed inside. PMA-1 provides the permanent connection point between Unity and Zarya; PMA-2 will serve as a Space Shuttle docking port. Zarya is a self-supporting active vehicle, providing propulsive control capability and power during the early assembly stages. It also has fuel storage capability

Effective team management by district nurses.

PubMed

Bliss, Julie

2004-12-01

This article considers the key role played by the district nurse in managing the district nursing team in order to provide high quality health care. It considers how the district nurse can use key managerial roles (interpersonal, informational and decision-making) in order to ensure unity within the team. The importance of shared goals and trust to achieve unity is explored and a strategy for managing conflict is discussed. Finally, the article suggests a set of ground rules which could be used to facilitate effective team working.

Advanced Technology Development for Stirling Convertors

NASA Technical Reports Server (NTRS)

Thieme, Lanny G.; Schreiber, Jeffrey G.

2004-01-01

A high-efficiency Stirling Radioisotope Generator (SRG) for use on potential NASA Space Science missions is being developed by the Department of Energy, Lockheed Martin, Stirling Technology Company, and NASA Glenn Research Center (GRC). These missions may include providing spacecraft onboard electric power for deep space missions or power for unmanned Mars rovers. GRC is also developing advanced technology for Stirling convertors, aimed at substantially improving the specific power and efficiency of the convertor and the overall power system. Performance and mass improvement goals have been established for second- and thirdgeneration Stirling radioisotope power systems. Multiple efforts are underway to achieve these goals, both in-house at GRC and under various grants and contracts. The status and results to date for these efforts will be discussed in this paper. Cleveland State University (CSU) is developing a multi-dimensional Stirling computational fluid dynamics code, capable of modeling complete convertors. A 2-D version of the code is now operational, and validation efforts at both CSU and the University of Minnesota are complementing the code development. A screening of advanced superalloy, refractory metal alloy, and ceramic materials has been completed, and materials have been selected for creep and joining characterization as part of developing a high-temperature heater head. A breadboard characterization is underway for an advanced controller using power electronics for active power factor control with a goal of eliminating the heavy tuning capacitors that are typically needed to achieve near unity power factors. Key Stirling developments just initiated under recent NRA (NASA Research Announcement) awards will also be discussed. These include a lightweight convertor to be developed by Sunpower Inc. and an advanced microfabricated regenerator to be done by CSU.

High performance ripple feedback for the buck unity-power-factor rectifier

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lo, Y.W.; King, R.J.

1995-03-01

The buck unity-power-factor rectifier has harmonic-free input current with complete load regulation down to zero output voltage. A new ``nonlinear ripple feedback`` is proposed which exactly cancels the spoiling effect of dc-side current ripple on the low-distortion ac line current waveforms, even for large amounts of ripple. This cancellation is independent of operating point and readily implemented with analog hardware, thereby permitting economies in the design of the dc filter while maintaining harmonic-free operation. Both large-signal and incremental analyses of the rectifier are given. Confirming experimental results from a 1-kW 48-V isolated battery charger operating with current-ripple levels ranging frommore » 50% to discontinuous-conduction-mode operation are given.« less

Near unity ultraviolet absorption in graphene without patterning

NASA Astrophysics Data System (ADS)

Zhu, Jinfeng; Yan, Shuang; Feng, Naixing; Ye, Longfang; Ou, Jun-Yu; Liu, Qing Huo

2018-04-01

Enhancing the light-matter interaction of graphene is an important issue for related photonic devices and applications. In view of its potential ultraviolet applications, we aim to achieve extremely high ultraviolet absorption in graphene without any nanostructure or microstructure patterning. By manipulating the polarization and angle of incident light, the ultraviolet power can be sufficiently coupled to the optical dissipation of graphene based on single-channel coherent perfect absorption in an optimized multilayered thin film structure. The ultraviolet absorbance ratios of single and four atomic graphene layers are enhanced up to 71.4% and 92.2%, respectively. Our research provides a simple and efficient scheme to trap ultraviolet light for developing promising photonic and optoelectronic devices based on graphene and potentially other 2D materials.

KSC-98pc1217

NASA Image and Video Library

1998-10-03

KENNEDY SPACE CENTER, FLA. -- Inside the payload bay of Space Shuttle orbiter Endeavour in Orbiter Processing Facility Bay 1, STS-88 Mission Specialists Jerry L. Ross (crouching at left) and James H. Newman (far right) get a close look at equipment. Looking on is Wayne Wedlake (far left), with United Space Alliance at Johnson Space Center, and a KSC worker (behind Newman) who is operating the movable work platform or bucket. The STS-88 crew members are participating in a Crew Equipment Interface Test (CEIT), familiarizing themselves with the orbiter's midbody and crew compartments. Targeted for liftoff on Dec. 3, 1998, STS-88 will be the first Space Shuttle launch for assembly of the International Space Station (ISS). The primary payload is the Unity connecting module which will be mated to the Russian-built Zarya control module, expected to be already on orbit after a November launch from Russia. After the mating, Ross and Newman are scheduled to perform three spacewalks to connect power, data and utility lines and install exterior equipment. The first major U.S.-built component of ISS, Unity will serve as a connecting passageway to living and working areas of the space station. Unity has two attached pressurized mating adapters (PMAs) and one stowage rack installed inside. PMA-1 provides the permanent connection point between Unity and Zarya; PMA-2 will serve as a Space Shuttle docking port. Zarya is a self-supporting active vehicle, providing propulsive control capability and power during the early assembly stages. It also has fuel storage capability

Terahertz quantum cascade lasers based on resonant phonon scattering for depopulation.

PubMed

Hu, Qing; Williams, Benjamin S; Kumar, Sushil; Callebaut, Hans; Reno, John L

2004-02-15

We report our development of terahertz (THz) quantum cascade lasers (QCLs), in which the depopulation of the lower radiative level is achieved through resonant longitudinal optical (LO) phonon scattering. This depopulation mechanism, similar to that implemented in all the QCLs operating at mid-infrared frequencies, is robust at high temperatures and high injection levels. The unique feature of resonant LO-phonon scattering in our THz QCL structures allows a highly selective depopulation of the lower radiative level with a sub-picosecond lifetime, while maintaining a relatively long upper level lifetime (more than 5 ps) that is due to upper-to-ground-state scattering. The first QCL based on this mechanism achieved lasing at 3.4 THz (lambda approximately 87 microm) up to 87 K for pulsed operations, with peak power levels exceeding 10 mW at ca. 40 K. Using a novel double-sided metal waveguide for mode confinement, which yields a unity mode confinement factor and therefore a low total cavity loss at THz frequencies, we have also achieved lasing at wavelengths longer than 100 microm.

Fixing the War Powers

DTIC Science & Technology

1992-04-01

strength and unity. Third, such a divided arrangement comported with the perceived need to resurrect balanced government where neither branch could...Either way, King’s statement comports with the framers’ view of the President’s war powers. Despite the poor record, one may fairly conclude that this...the model for the war powers comports with the framers’ intellectual foundations. They divided the powers between two coordinate branches to prevent

Progress in Noise Thermometry at 505 K and 693 K Using Quantized Voltage Noise Ratio Spectra

NASA Astrophysics Data System (ADS)

Tew, W. L.; Benz, S. P.; Dresselhaus, P. D.; Coakley, K. J.; Rogalla, H.; White, D. R.; Labenski, J. R.

2010-09-01

Technical advances and new results in noise thermometry at temperatures near the tin freezing point and the zinc freezing point using a quantized voltage noise source (QVNS) are reported. The temperatures are derived by comparing the power spectral density of QVNS synthesized noise with that of Johnson noise from a known resistance at both 505 K and 693 K. Reference noise is digitally synthesized so that the average power spectra of the QVNS match those of the thermal noise, resulting in ratios of power spectra close to unity in the low-frequency limit. Three-parameter models are used to account for differences in impedance-related time constants in the spectra. Direct comparison of noise temperatures to the International Temperature Scale of 1990 (ITS-90) is achieved in a comparison furnace with standard platinum resistance thermometers. The observed noise temperatures determined by operating the noise thermometer in both absolute and relative modes, and related statistics together with estimated uncertainties are reported. The relative noise thermometry results are combined with results from other thermodynamic determinations at temperatures near the tin freezing point to calculate a value of T - T 90 = +4(18) mK for temperatures near the zinc freezing point. These latest results achieve a lower uncertainty than that of our earlier efforts. The present value of T - T 90 is compared to other published determinations from noise thermometry and other methods.

Prospects of low-dimensional and nanostructured silicon-based thermoelectric materials: findings from theory and simulation

NASA Astrophysics Data System (ADS)

Neophytou, Neophytos

2015-04-01

Silicon based low-dimensional materials receive significant attention as new generation thermoelectric materials after they have demonstrated record low thermal conductivities. Very few works to-date, however, report significant advances with regards to the power factor. In this review we examine possibilities of power factor enhancement in: (i) low-dimensional Si channels and (ii) nanocrystalline Si materials. For low-dimensional channels we use atomistic simulations and consider ultra-narrow Si nanowires and ultra-thin Si layers of feature sizes below 15 nm. Room temperature is exclusively considered. We show that, in general, low-dimensionality does not offer possibilities for power factor improvement, because although the Seebeck coefficient could slightly increase, the conductivity inevitably degrades at a much larger extend. The power factor in these channels, however, can be optimized by proper choice of geometrical parameters such as the transport orientation, confinement orientation, and confinement length scale. Our simulations show that in the case where room temperature thermal conductivities as low as κ l = 2 W/mK are achieved, the ZT figure of merit of an optimized Si low-dimensional channel could reach values around unity. For the second case of materials, we show that by making effective use of energy filtering, and taking advantage of the inhomogeneity within the nanocrystalline geometry, the underlying potential profile and dopant distribution large improvements in the thermoelectric power factor can be achieved. The paper is intended to be a review of the main findings with regards to the thermoelectric performance of nanoscale Si through our simulation work as well as through recent experimental observations.

Robust wireless power transfer using a nonlinear parity-time-symmetric circuit.

PubMed

Assawaworrarit, Sid; Yu, Xiaofang; Fan, Shanhui

2017-06-14

Considerable progress in wireless power transfer has been made in the realm of non-radiative transfer, which employs magnetic-field coupling in the near field. A combination of circuit resonance and impedance transformation is often used to help to achieve efficient transfer of power over a predetermined distance of about the size of the resonators. The development of non-radiative wireless power transfer has paved the way towards real-world applications such as wireless powering of implantable medical devices and wireless charging of stationary electric vehicles. However, it remains a fundamental challenge to create a wireless power transfer system in which the transfer efficiency is robust against the variation of operating conditions. Here we propose theoretically and demonstrate experimentally that a parity-time-symmetric circuit incorporating a nonlinear gain saturation element provides robust wireless power transfer. Our results show that the transfer efficiency remains near unity over a distance variation of approximately one metre, without the need for any tuning. This is in contrast with conventional methods where high transfer efficiency can only be maintained by constantly tuning the frequency or the internal coupling parameters as the transfer distance or the relative orientation of the source and receiver units is varied. The use of a nonlinear parity-time-symmetric circuit should enable robust wireless power transfer to moving devices or vehicles.

Robust wireless power transfer using a nonlinear parity-time-symmetric circuit

NASA Astrophysics Data System (ADS)

Assawaworrarit, Sid; Yu, Xiaofang; Fan, Shanhui

2017-06-01

Considerable progress in wireless power transfer has been made in the realm of non-radiative transfer, which employs magnetic-field coupling in the near field. A combination of circuit resonance and impedance transformation is often used to help to achieve efficient transfer of power over a predetermined distance of about the size of the resonators. The development of non-radiative wireless power transfer has paved the way towards real-world applications such as wireless powering of implantable medical devices and wireless charging of stationary electric vehicles. However, it remains a fundamental challenge to create a wireless power transfer system in which the transfer efficiency is robust against the variation of operating conditions. Here we propose theoretically and demonstrate experimentally that a parity-time-symmetric circuit incorporating a nonlinear gain saturation element provides robust wireless power transfer. Our results show that the transfer efficiency remains near unity over a distance variation of approximately one metre, without the need for any tuning. This is in contrast with conventional methods where high transfer efficiency can only be maintained by constantly tuning the frequency or the internal coupling parameters as the transfer distance or the relative orientation of the source and receiver units is varied. The use of a nonlinear parity-time-symmetric circuit should enable robust wireless power transfer to moving devices or vehicles.

Demonstration of Cosmic Microwave Background Delensing Using the Cosmic Infrared Background.

PubMed

Larsen, Patricia; Challinor, Anthony; Sherwin, Blake D; Mak, Daisy

2016-10-07

Delensing is an increasingly important technique to reverse the gravitational lensing of the cosmic microwave background (CMB) and thus reveal primordial signals the lensing may obscure. We present a first demonstration of delensing on Planck temperature maps using the cosmic infrared background (CIB). Reversing the lensing deflections in Planck CMB temperature maps using a linear combination of the 545 and 857 GHz maps as a lensing tracer, we find that the lensing effects in the temperature power spectrum are reduced in a manner consistent with theoretical expectations. In particular, the characteristic sharpening of the acoustic peaks of the temperature power spectrum resulting from successful delensing is detected at a significance of 16σ, with an amplitude of A_{delens}=1.12±0.07 relative to the expected value of unity. This first demonstration on data of CIB delensing, and of delensing techniques in general, is significant because lensing removal will soon be essential for achieving high-precision constraints on inflationary B-mode polarization.

Oxide Thermoelectric Materials: A Structure-Property Relationship

NASA Astrophysics Data System (ADS)

Nag, Abanti; Shubha, V.

2014-04-01

Recent demand for thermoelectric materials for power harvesting from automobile and industrial waste heat requires oxide materials because of their potential advantages over intermetallic alloys in terms of chemical and thermal stability at high temperatures. Achievement of thermoelectric figure of merit equivalent to unity ( ZT ≈ 1) for transition-metal oxides necessitates a second look at the fundamental theory on the basis of the structure-property relationship giving rise to electron correlation accompanied by spin fluctuation. Promising transition-metal oxides based on wide-bandgap semiconductors, perovskite and layered oxides have been studied as potential candidate n- and p-type materials. This paper reviews the correlation between the crystal structure and thermoelectric properties of transition-metal oxides. The crystal-site-dependent electronic configuration and spin degeneracy to control the thermopower and electron-phonon interaction leading to polaron hopping to control electrical conductivity is discussed. Crystal structure tailoring leading to phonon scattering at interfaces and nanograin domains to achieve low thermal conductivity is also highlighted.

Achieving Peace through Education.

ERIC Educational Resources Information Center

Clarken, Rodney H.

While it is generally agreed that peace is desirable, there are barriers to achieving a peaceful world. These barriers are classified into three major areas: (1) an erroneous view of human nature; (2) injustice; and (3) fear of world unity. In a discussion of these barriers, it is noted that although the consciousness and conscience of the world…

Integrated three-dimensional photonic nanostructures for achieving near-unity solar absorption and superhydrophobicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuang, Ping; Lin, Shawn-Yu, E-mail: sylin@rpi.edu; Hsieh, Mei-Li

2015-06-07

In this paper, we proposed and realized 3D photonic nanostructures consisting of ultra-thin graded index antireflective coatings (ARCs) and woodpile photonic crystals. The use of the integrated ARC and photonic crystal structure can achieve broadband, broad-angle near unity solar absorption. The amorphous silicon based photonic nanostructure experimentally shows an average absorption of ∼95% for λ = 400–620 nm over a wide angular acceptance of θ = 0°–60°. Theoretical studies show that a Gallium Arsenide (GaAs) based structure can achieve an average absorption of >95% for λ = 400–870 nm. Furthermore, the use of the slanted SiO{sub 2} nanorod ARC surface layer by glancing angle deposition exhibits Cassie-Baxter statemore » wetting, and superhydrophobic surface is obtained with highest water contact angle θ{sub CB} ∼ 153°. These properties are fundamentally important for achieving maximum solar absorption and surface self-cleaning in thin film solar cell applications.« less

System and component design and test of a 10 hp, 18,000 rpm AC dynamometer utilizing a high frequency AC voltage link, part 1

NASA Technical Reports Server (NTRS)

Lipo, Thomas A.; Alan, Irfan

1991-01-01

Hard and soft switching test results conducted with one of the samples of first generation MOS-controlled thyristor (MCTs) and similar test results with several different samples of second generation MCT's are reported. A simple chopper circuit is used to investigate the basic switching characteristics of MCT under hard switching and various types of resonant circuits are used to determine soft switching characteristics of MCT under both zero voltage and zero current switching. Next, operation principles of a pulse density modulated converter (PDMC) for three phase (3F) to 3F two-step power conversion via parallel resonant high frequency (HF) AC link are reviewed. The details for the selection of power switches and other power components required for the construction of the power circuit for the second generation 3F to 3F converter system are discussed. The problems encountered in the first generation system are considered. Design and performance of the first generation 3F to 3F power converter system and field oriented induction moter drive based upon a 3 kVA, 20 kHz parallel resonant HF AC link are described. Low harmonic current at the input and output, unity power factor operation of input, and bidirectional flow capability of the system are shown via both computer and experimental results. The work completed on the construction and testing of the second generation converter and field oriented induction motor drive based upon specifications for a 10 hp squirrel cage dynamometer and a 20 kHz parallel resonant HF AC link is discussed. The induction machine is designed to deliver 10 hp or 7.46 kW when operated as an AC-dynamo with power fed back to the source through the converter. Results presented reveal that the proposed power level requires additional energy storage elements to overcome difficulties with a peak link voltage variation problem that limits reaching to the desired power level. The power level test of the second generation converter after the addition of extra energy storage elements to the HF link are described. The importance of the source voltage level to achieve a better current regulation for the source side PDMC is also briefly discussed. The power levels achieved in the motoring mode of operation show that the proposed power levels achieved in the generating mode of operation can also be easily achieved provided that no mechanical speed limitation were present to drive the induction machine at the proposed power level.

KSC-98pc1216

NASA Image and Video Library

1998-10-03

KENNEDY SPACE CENTER, FLA. -- Inside the payload bay of Space Shuttle orbiter Endeavour, workers and STS-88 crew members on a movable work platform or bucket move closer to the rear of the orbiter's crew compartment. While Endeavour is being prepared for flight inside Orbiter Processing Facility Bay 1, the STS-88 crew members are participating in a Crew Equipment Interface Test (CEIT) to familiarize themselves with the orbiter's midbody and crew compartments. A KSC worker (left) maneuvers the platform to give Mission Specialists Jerry L. Ross and James H. Newman (right) a closer look. Looking on is Wayne Wedlake of United Space Alliance at Johnson Space Center. Targeted for liftoff on Dec. 3, 1998, STS-88 will be the first Space Shuttle launch for assembly of the International Space Station (ISS). The primary payload is the Unity connecting module which will be mated to the Russian-built Zarya control module, expected to be already on orbit after a November launch from Russia. After the mating, Ross and Newman are scheduled to perform three spacewalks to connect power, data and utility lines and install exterior equipment. The first major U.S.-built component of ISS, Unity will serve as a connecting passageway to living and working areas of the space station. Unity has two attached pressurized mating adapters (PMAs) and one stowage rack installed inside. PMA-1 provides the permanent connection point between Unity and Zarya; PMA-2 will serve as a Space Shuttle docking port. Zarya is a self-supporting active vehicle, providing propulsive control capability and power during the early assembly stages. It also has fuel storage capability

KSC-98pc1222

NASA Image and Video Library

1998-10-03

KENNEDY SPACE CENTER, FLA. -- As the bucket operator (left) lowers them into the open payload bay of the orbiter Endeavour, STS-88 Mission Specialists Jerry L. Ross (second from left) and James H. Newman (second from right) do a sharp-edge inspection. At their right is Wayne Wedlake, with United Space Alliance at Johnson Space Center. Below them is the Orbiter Docking System, the remote manipulator system arm and a tunnel into the payload bay. The STS-88 crew members are participating in a Crew Equipment Interface Test (CEIT), familiarizing themselves with the orbiter's midbody and crew compartments. Targeted for liftoff on Dec. 3, 1998, STS-88 will be the first Space Shuttle launch for assembly of the International Space Station (ISS). The primary payload is the Unity connecting module which will be mated to the Russian-built Zarya control module, expected to be already on orbit after a November launch from Russia. After the mating, Ross and Newman are scheduled to perform three spacewalks to connect power, data and utility lines and install exterior equipment. The first major U.S.-built component of ISS, Unity will serve as a connecting passageway to living and working areas of the space station. Unity has two attached pressurized mating adapters (PMAs) and one stowage rack installed inside. PMA-1 provides the permanent connection point between Unity and Zarya; PMA-2 will serve as a Space Shuttle docking port. Zarya is a self-supporting active vehicle, providing propulsive control capability and power during the early assembly stages. It also has fuel storage capability

Julius Sachs (1832–1897) and the Unity of Life

PubMed Central

Kutschera, Ulrich; Baluška, František

2015-01-01

In 1865, the German botanist Julius Sachs published a seminal monograph entitled Experimental-Physiologie der Pflanzen (Experimental Physiology of Plants) and hence became the founder of a new scientific discipline that originated 150 y ago. Here, we outline the significance of the achievements of Sachs. In addition, we document, with reference to his Vorlesungen über Pflanzen-Physiologie (Lectures on the Physiology of Plants, 1882), that Sachs was one of the first experimentalists who proposed the functional unity of all organisms alive today (humans, animals, plants and other “vegetable” organisms, such as algae, cyanophyceae, fungi, myxomycetes, and bacteria). PMID:26359706

Install of Cygnus controller cable

NASA Image and Video Library

2014-07-15

ISS040-E-063760 (15 July 2014) --- European Space Agency astronaut Alexander Gerst, Expedition 40 flight engineer, works with power and data cables in the vestibule between the Destiny laboratory and Unity node of the International Space Station.

A Compact Operational Amplifier with Load-Insensitive Stability Compensation for High-Precision Transducer Interface.

PubMed

Yu, Zhanghao; Yang, Xi; Chung, SungWon

2018-01-29

High-resolution electronic interface circuits for transducers with nonlinear capacitive impedance need an operational amplifier, which is stable for a wide range of load capacitance. Such operational amplifier in a conventional design requires a large area for compensation capacitors, increasing costs and limiting applications. In order to address this problem, we present a gain-boosted two-stage operational amplifier, whose frequency response compensation capacitor size is insensitive to the load capacitance and also orders of magnitude smaller compared to the conventional Miller-compensation capacitor that often dominates chip area. By exploiting pole-zero cancellation between a gain-boosting stage and the main amplifier stage, the compensation capacitor of the proposed operational amplifier becomes less dependent of load capacitance, so that it can also operate with a wide range of load capacitance. A prototype operational amplifier designed in 0.13-μm complementary metal-oxide-semiconductor (CMOS) with a 400-fF compensation capacitor occupies 900- μ m 2 chip area and achieves 0.022-2.78-MHz unity gain bandwidth and over 65 ∘ phase margin with a load capacitance of 0.1-15 nF. The prototype amplifier consumes 7.6 μ W from a single 1.0-V supply. For a given compensation capacitor size and a chip area, the prototype design demonstrates the best reported performance trade-off on unity gain bandwidth, maximum stable load capacitance, and power consumption.

Enhanced Charge Carrier Transport and Device Performance Through Dual-Cesium Doping in Mixed-Cation Perovskite Solar Cells with Near Unity Free Carrier Ratios.

PubMed

Ye, Tao; Petrović, Miloš; Peng, Shengjie; Yoong, Jeremy Lee Kong; Vijila, Chellappan; Ramakrishna, Seeram

2017-01-25

PbI 2 -enriched mixed perovskite film [FA 0.81 MA 0.15 Pb(I 0.836 Br 0.15 ) 3 ] has been widely studied due to its great potential in perovskite solar cell (PSC) applications. Herein, a FA 0.81 MA 0.15 Pb(I 0.836 Br 0.15 ) 3 film has been fabricated with the temperature-dependent optical absorption spectra utilized to determine its exciton binding energy. A ∼13 meV exciton binding energy is estimated, and a near-unity fraction of free carriers out of the total photoexcitons has been obtained in the solar cell operating regime at equilibrium state. PSCs are fabricated with this mixed perovskite film, but a significant electron transport barrier at the TiO 2 -perovskite interface limited their performance. Cs 2 CO 3 and CsI are then utilized as functional enhancers with which to substantially balance the electron and hole transport and increase the carriers (both electrons and holes) mobilities in PSCs, resulting in much-improved solar-cell performance. The modified PSCs exhibit reproducible power conversion efficiency (PCE) values with little hysteresis effect in the J-V curves, achieving PCEs up to 19.5% for the Cs 2 CO 3 -modified PSC and 20.6% when subsequently further doped with CsI.

Measuring Radiofrequency and Microwave Radiation from Varying Signal Strengths

NASA Technical Reports Server (NTRS)

Davis, Bette; Gaul, W. C.

2007-01-01

This viewgraph presentation discusses the process of measuring radiofrequency and microwave radiation from various signal strengths. The topics include: 1) Limits and Guidelines; 2) Typical Variable Standard (IEEE) Frequency Dependent; 3) FCC Standard 47 CFR 1.1310; 4) Compliance Follows Unity Rule; 5) Multiple Sources Contribute; 6) Types of RF Signals; 7) Interfering Radiations; 8) Different Frequencies Different Powers; 9) Power Summing - Peak Power; 10) Contribution from Various Single Sources; 11) Total Power from Multiple Sources; 12) Are You Out of Compliance?; and 13) In Compliance.

A simple proof of a lemma of Coleman

NASA Astrophysics Data System (ADS)

Saikia, A.

2001-03-01

Let p be an odd prime. The results in this paper concern the units of the infinite extension of Qp generated by all p-power roots of unity. Letformula herewhere [mu]pn+1 denote the pn+1th roots of 1. Let [script p]n be the maximal ideal of the ring of integers of [Phi]n and let Un be the units congruent to 1 modulo [script p]n.Let [zeta]n be a fixed primitive pn+1th root of unity such that [zeta]pn = [zeta]n [minus sign] 1, [for all]n [gt-or-equal, slanted] 1. Put [pi]n = [zeta]n [minus sign] 1. Thus [pi]n is a local parameter for [Phi]n. Letformula hereKummer already exploited the obvious fact that every u0 [set membership] U0 can be written in the formformula herewhere f0(T) is some power series in Zp[[T

Performance of Four-Leg VSC based DSTATCOM using Single Phase P-Q Theory

NASA Astrophysics Data System (ADS)

Jampana, Bangarraju; Veramalla, Rajagopal; Askani, Jayalaxmi

2017-02-01

This paper presents single-phase P-Q theory for four-leg VSC based distributed static compensator (DSTATCOM) in the distribution system. The proposed DSTATCOM maintains unity power factor at source, zero voltage regulation, eliminates current harmonics, load balancing and neutral current compensation. The advantage of using four-leg VSC based DSTATCOM is to eliminate isolated/non-isolated transformer connection at point of common coupling (PCC) for neutral current compensation. The elimination of transformer connection at PCC with proposed topology will reduce cost of DSTATCOM. The single-phase P-Q theory control algorithm is used to extract fundamental component of active and reactive currents for generation of reference source currents which is based on indirect current control method. The proposed DSTATCOM is modelled and the results are validated with various consumer loads under unity power factor and zero voltage regulation modes in the MATLAB R2013a environment using simpower system toolbox.

Optical gyroscope with controllable dispersion in four wave mixing regime.

NASA Astrophysics Data System (ADS)

Mikhailov, Eugeniy; Wolfe, Owen; Du, Shuangli; Rochester, Simon; Budker, Dmitry; Novikova, Irina

2016-05-01

We present our work towards realization of the fast-light gyroscope prototype, in which the sensitivity enhancement (compared to a regular laser gyroscopes) is achieved by adjusting the intra-cavity dispersion. We discuss schematics and underlying nonlinear effects leading to the negative dispersion in Rb vapor: level structure, optically addressed transitions, and configuration of the resonant cavity. We investigate dependence of the pulling factor (i.e., the ratio of the lasing frequency shift with the change of the cavity length to the equivalent resonance frequency shift in the empty cavity) on pump lasers detunings, power, and density of the atomic vapor. The observation of the pulling factor exceeding unity implies the gyroscope sensitivity improvement over the regular system This work is supported by Naval Air Warfare Center STTR program N68335-11-C-0428.

High Confinement Mode and Edge Localized Mode Characteristics in a Near-Unity Aspect Ratio Tokamak.

PubMed

Thome, K E; Bongard, M W; Barr, J L; Bodner, G M; Burke, M G; Fonck, R J; Kriete, D M; Perry, J M; Schlossberg, D J

2016-04-29

Tokamak experiments at near-unity aspect ratio A≲1.2 offer new insights into the self-organized H-mode plasma confinement regime. In contrast to conventional A∼3 plasmas, the L-H power threshold P_{LH} is ∼15× higher than scaling predictions, and it is insensitive to magnetic topology, consistent with modeling. Edge localized mode (ELM) instabilities shift to lower toroidal mode numbers as A decreases. These ultralow-A operations enable heretofore inaccessible J_{edge}(R,t) measurements through an ELM that show a complex multimodal collapse and the ejection of a current-carrying filament.

High confinement mode and edge localized mode characteristics in a near-unity aspect ratio tokamak

DOE PAGES

Thome, Kathreen E.; Bongard, Michael W.; Barr, Jayson L.; ...

2016-04-27

Tokamak experiments at near-unity aspect ratio A ≲ 1.2 offer new insights into the self-organized H-mode plasma confinement regime. In contrast to conventional A ~ 3 plasmas, the L–H power threshold P LH is ~15× higher than scaling predictions, and it is insensitive to magnetic topology, consistent with modeling. Edge localized mode (ELM) instabilities shift to lower toroidal mode numbers as A decreases. Furthermore, these ultralow-A operations enable heretofore inaccessible J edge(R,t) measurements through an ELM that show a complex multimodal collapse and the ejection of a current-carrying filament.

STS-88 Mission Specialists Currie and Ross inside Endeavour

NASA Technical Reports Server (NTRS)

1998-01-01

STS-88 Mission Specialists Nancy J. Currie, Ph.D., (back) and Jerry L. Ross (front) check over equipment inside orbiter Endeavour during Terminal Countdown Demonstration Activities (TCDT). The TCDT includes mission familiarization activities, emergency egress training, and the simulated main engine cut-off exercise. Mission STS-88 is targeted for launch on Dec. 3, 1998. It is the first U.S. flight for the assembly of the International Space Station and will carry the Unity connecting module. Unity will be mated with the already orbiting Russian-built Zarya control module. The 12-day mission includes three planned spacewalks to connect power, data and utility lines and install exterior equipment.

Inverter for interfacing advanced energy sources to a utility grid

DOEpatents

Steigerwald, Robert L.

1984-01-01

A transistor is operated in the PWM mode such that a hlaf sine wave of current is delivered first to one-half of a distribution transformer and then the other as determined by steering thyristors operated at the fundamental sinusoidal frequency. Power to the transistor is supplied by a dc source such as a solar array and the power is converted such that a sinusoidal current is injected into a utility at near unity power factor.

Principles of light harvesting from single photosynthetic complexes.

PubMed

Schlau-Cohen, G S

2015-06-06

Photosynthetic systems harness sunlight to power most life on Earth. In the initial steps of photosynthetic light harvesting, absorbed energy is converted to chemical energy with near-unity quantum efficiency. This is achieved by an efficient, directional and regulated flow of energy through a network of proteins. Here, we discuss the following three key principles of this flow and of photosynthetic light harvesting: thermal fluctuations of the protein structure; intrinsic conformational switches with defined functional consequences; and environmentally triggered conformational switches. Through these principles, photosynthetic systems balance two types of operational costs: metabolic costs, or the cost of maintaining and running the molecular machinery, and opportunity costs, or the cost of losing any operational time. Understanding how the molecular machinery and dynamics are designed to balance these costs may provide a blueprint for improved artificial light-harvesting devices. With a multi-disciplinary approach combining knowledge of biology, this blueprint could lead to low-cost and more effective solar energy conversion. Photosynthetic systems achieve widespread light harvesting across the Earth's surface; in the face of our growing energy needs, this is functionality we need to replicate, and perhaps emulate.

Generation of uniformly oriented in-plane magnetization with near-unity purity in 4π microscopy.

PubMed

Wang, Sicong; Cao, Yaoyu; Li, Xiangping

2017-12-01

In this Letter, we numerically demonstrate the all-optical generation of uniformly oriented in-plane magnetization with near-unity purity (more than 99%) under a 4π microscopic configuration. This is achieved through focusing two counter-propagating vector beams consisting of coherently configured linear and radial components. Based on the Debye diffraction theory, constructive and destructive interferences of the focal field components can be tailored under the 4π configuration to generate high-purity uniformly polarized transverse and longitudinal electric-field components in the center of the focal region. Consequently, near-unity purity in-plane magnetization with a uniform orientation within the focal volume defined by the full width at half-maximum can be created through the inverse Faraday effect. In addition, it reveals that the purity of the in-plane magnetization is robust against the numerical aperture of the focal lens. This result expands the flexibility of magnetization manipulations through light and holds great potential in all-optical magnetic recording and spintronics.

[Carl Friedrich von Weizsäcker's design of a unity of physics].

PubMed

Görnitz, Thomas

2014-01-01

As I learned in many conversations with Carl Friedrich von Weizsäcker, he saw his place in the history of science deriving from his "Theory of Urs". This theory will establish the unity of science on the basis of quantum bits. Any attempts to find some "fundamental bricks"--of whatever kind--must fail because of the antinomies of atomism. An abstract quantum bit is a structure quantum that cannot be conceived as a particle in space and time. However, it is clear, solely for logical reasons, that a quantum bit is an ultimate and indecomposable entity. Weizsäcker's revolutionary goal was--already 50 years ago--to unite quantum theory with cosmology and, on these grounds, proceed to a theory of elementary particles. The article gives a short overview of Weizsäcker's approach to the unity of physics, ending with a brief summary of what has been achieved in that endeavour up to now.

Thin-film thermoelectric devices with high room-temperature figures of merit.

PubMed

Venkatasubramanian, R; Siivola, E; Colpitts, T; O'Quinn, B

2001-10-11

Thermoelectric materials are of interest for applications as heat pumps and power generators. The performance of thermoelectric devices is quantified by a figure of merit, ZT, where Z is a measure of a material's thermoelectric properties and T is the absolute temperature. A material with a figure of merit of around unity was first reported over four decades ago, but since then-despite investigation of various approaches-there has been only modest progress in finding materials with enhanced ZT values at room temperature. Here we report thin-film thermoelectric materials that demonstrate a significant enhancement in ZT at 300 K, compared to state-of-the-art bulk Bi2Te3 alloys. This amounts to a maximum observed factor of approximately 2.4 for our p-type Bi2Te3/Sb2Te3 superlattice devices. The enhancement is achieved by controlling the transport of phonons and electrons in the superlattices. Preliminary devices exhibit significant cooling (32 K at around room temperature) and the potential to pump a heat flux of up to 700 W cm-2; the localized cooling and heating occurs some 23,000 times faster than in bulk devices. We anticipate that the combination of performance, power density and speed achieved in these materials will lead to diverse technological applications: for example, in thermochemistry-on-a-chip, DNA microarrays, fibre-optic switches and microelectrothermal systems.

Efficient Plasma Production in Low Background Neutral Pressures with the M2P2 Prototype

NASA Technical Reports Server (NTRS)

Ziemba, T.; Euripides, P.; Winglee, R.; Slough, J.; Giersch, L.

2003-01-01

Mini-Magnetospheric Plasma Propulsion (M2P2) seeks the creation of a large-scale (10 km radius) magnetic wall or bubble (i.e. a magnetosphere) by the electromagnetic inflation of a small-scale (20 cm radius) dipole magnet. The inflated magnetosphere will intercept the solar wind and thereby provide high-speed propulsion with modest power and fuel requirements due to the gain provided by the ambient medium. Magnetic field inflation is produced by the injection of plasma onto the dipole magnetic field eliminating the need for large mechanical structures and added material weight at launch. For successful inflation of the magnetic bubble a beta near unity must be achieved along the imposed dipole field. This is dependent on the plasma parameters that can be achieved with a plasma source that provide continuous operation at the desired power levels of 1 to 2 kilowatts. Over the last two years we have been developing a laboratory prototype to demonstrate the inflation of the magnetic field under space-like conditions. In this paper we will present some of the latest results from the prototype development at the University of Washington and show that the prototype can produce high ionization efficiencies while operating in near space like neutral background pressures producing electron temperatures of a few tens of electron volts. This allows for operation with propellant expenditures lower than originally estimated.

Ethnic Education Should Undertake the Major Historic Task of Ethnic Unity and the Possibility of and Explorations into the Localization of Diversified Education

ERIC Educational Resources Information Center

Minhui, Qian

2010-01-01

This article argues that the choice of cultures by ethnic education was determined by a given form of elitist ideology and a power agency. After the conversion of China's society from a planned economy to a market economy, this elitist ideology and power agency has become diversified and includes the elitist ideology of statism. Empowerment has…

Photonic Materials and Devices for RF (mmW) Sensing and Imaging

DTIC Science & Technology

2012-12-31

wave encoding thereby eliminating the need for bulky LO distribution cables. Also, optical processing techniques can be utilized to provide simple... optical powers, can be close to unity and low -noise photodetectors make the detection of exceedingly low power millimeter-waves practical. In... optically -filtering the modulated signal to pass only a single sideband and detecting the resultant optical signal with a low -noise photodetector we have

The Influence of Relationship Power Dynamics on HIV Testing in Rural Malawi

PubMed Central

Conroy, Amy A.

2014-01-01

Using the theory of gender and power (TGP) and data from the Tsogolo la Thanzi (TLT) study, we examined how relationship power shapes young people’s decisions to test for HIV in rural Malawi (N=932), a high-HIV prevalence setting undergoing rapid expansions in testing services. We used generalized estimating equations (GEE) to examine associations among five constructs of relationship power (socioeconomic inequalities, relationship dominance, relationship violence, relationship unity, and mistrust), perceived risk, and receiving an HIV test over a 16-month period. The results indicate that young Malawians are testing for HIV at relatively high rates, repeatedly, and not just during pregnancy. Over the study period, 47.3% of respondents received at least one HIV test outside of TLT (range: 0–4). The GEE analysis revealed that men and women with higher levels of relationship unity were less likely to test for HIV. For men, being a victim of sexual coercion was an additional barrier to testing. Women’s testing decisions were more strongly influenced by perceptions of a partner’s risk for HIV than their own, whereas men relied more on self-assessments. The results highlight that testing decisions are deeply embedded within the relationship context, which should be considered in future HIV testing interventions. PMID:24670263

RAPID RESCUE: BREAKING THE MOLD OF ROUTINE CONTINGENCY RESPONSE FOR PERSONNEL RECOVERY

DTIC Science & Technology

2016-10-23

ultimately lead to timelier response and greater economy of force for an already critically strained Air Force core function. 1 INTRODUCTION...achieve economy of force. When an OPLAN calls for PR, a capability is requested rather than individual unit. The existing UTCs are too rigid and...the combatant commander and operational planners to achieve unity and economy of force without exceeding PR capacity.61 Tactical Employment

A Compact Operational Amplifier with Load-Insensitive Stability Compensation for High-Precision Transducer Interface

PubMed Central

Yang, Xi

2018-01-01

High-resolution electronic interface circuits for transducers with nonlinear capacitive impedance need an operational amplifier, which is stable for a wide range of load capacitance. Such operational amplifier in a conventional design requires a large area for compensation capacitors, increasing costs and limiting applications. In order to address this problem, we present a gain-boosted two-stage operational amplifier, whose frequency response compensation capacitor size is insensitive to the load capacitance and also orders of magnitude smaller compared to the conventional Miller-compensation capacitor that often dominates chip area. By exploiting pole-zero cancellation between a gain-boosting stage and the main amplifier stage, the compensation capacitor of the proposed operational amplifier becomes less dependent of load capacitance, so that it can also operate with a wide range of load capacitance. A prototype operational amplifier designed in 0.13-μm complementary metal–oxide–semiconductor (CMOS) with a 400-fF compensation capacitor occupies 900-μm2 chip area and achieves 0.022–2.78-MHz unity gain bandwidth and over 65∘ phase margin with a load capacitance of 0.1–15 nF. The prototype amplifier consumes 7.6 μW from a single 1.0-V supply. For a given compensation capacitor size and a chip area, the prototype design demonstrates the best reported performance trade-off on unity gain bandwidth, maximum stable load capacitance, and power consumption. PMID:29382183

Near-Unity Quantum Yields of Biexciton Emission from CdSe=CdS Nanocrystals Measured Using Single-Particle Spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Young-Shin; Malko, Anton V.; Vela, Javier

2011-05-03

Biexciton photoluminescence (PL) quantum yields (Q 2X) of individual CdSe/CdS core-shell nanocrystal quantum dots with various shell thicknesses are derived from independent PL saturation and two-photon correlation measurements. We observe a near-unity Q{sub 2X} for some nanocrystals with an ultrathick 19-monolayer shell. High Q 2X’s are, however, not universal and vary widely among nominally identical nanocrystals indicating a significant dependence of Q 2X upon subtle structural differences. Interestingly, our measurements indicate that high Q 2X’s are not required to achieve complete suppression of PL intensity fluctuations in individual nanocrystals.

Waveguide integrated superconducting single-photon detectors with high internal quantum efficiency at telecom wavelengths

PubMed Central

Kahl, Oliver; Ferrari, Simone; Kovalyuk, Vadim; Goltsman, Gregory N.; Korneev, Alexander; Pernice, Wolfram H. P.

2015-01-01

Superconducting nanowire single-photon detectors (SNSPDs) provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, compatibility with an integrated optical platform is a crucial requirement for applications in emerging quantum photonic technologies. Here we present SNSPDs embedded in nanophotonic integrated circuits which achieve internal quantum efficiencies close to unity at 1550 nm wavelength. This allows for the SNSPDs to be operated at bias currents far below the critical current where unwanted dark count events reach milli-Hz levels while on-chip detection efficiencies above 70% are maintained. The measured dark count rates correspond to noise-equivalent powers in the 10−19 W/Hz−1/2 range and the timing jitter is as low as 35 ps. Our detectors are fully scalable and interface directly with waveguide-based optical platforms. PMID:26061283

Waveguide integrated superconducting single-photon detectors with high internal quantum efficiency at telecom wavelengths.

PubMed

Kahl, Oliver; Ferrari, Simone; Kovalyuk, Vadim; Goltsman, Gregory N; Korneev, Alexander; Pernice, Wolfram H P

2015-06-10

Superconducting nanowire single-photon detectors (SNSPDs) provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, compatibility with an integrated optical platform is a crucial requirement for applications in emerging quantum photonic technologies. Here we present SNSPDs embedded in nanophotonic integrated circuits which achieve internal quantum efficiencies close to unity at 1550 nm wavelength. This allows for the SNSPDs to be operated at bias currents far below the critical current where unwanted dark count events reach milli-Hz levels while on-chip detection efficiencies above 70% are maintained. The measured dark count rates correspond to noise-equivalent powers in the 10(-19) W/Hz(-1/2) range and the timing jitter is as low as 35 ps. Our detectors are fully scalable and interface directly with waveguide-based optical platforms.

Tyurin works on a CPA in the hatch between the MPLM and Node 1

NASA Image and Video Library

2001-08-01

ISS003-E-5136 (August 2001) --- Mikhail Tyurin of Rosaviakosmos, Expedition Three flight engineer, secures a connection on a Controller Power Assembly (CPA) in a hatchway on Unity Node 1. This image was taken with a digital still camera.

One Veteran Counselor's Take on the Future of Rehabilitation Counseling

ERIC Educational Resources Information Center

McMahon, Brian T.

2009-01-01

One counselor argues that rehabilitation counseling has a bright future that will be better still if it recommits to vocational services, achieves organizational unity (not just coordination), remains true to its core values, and increases collaboration with cross-disability organizations. (Contains 1 table.)

The correlation function for density perturbations in an expanding universe. IV - The evolution of the correlation function. [galaxy distribution

NASA Technical Reports Server (NTRS)

Mcclelland, J.; Silk, J.

1979-01-01

The evolution of the two-point correlation function for the large-scale distribution of galaxies in an expanding universe is studied on the assumption that the perturbation densities lie in a Gaussian distribution centered on any given mass scale. The perturbations are evolved according to the Friedmann equation, and the correlation function for the resulting distribution of perturbations at the present epoch is calculated. It is found that: (1) the computed correlation function gives a satisfactory fit to the observed function in cosmological models with a density parameter (Omega) of approximately unity, provided that a certain free parameter is suitably adjusted; (2) the power-law slope in the nonlinear regime reflects the initial fluctuation spectrum, provided that the density profile of individual perturbations declines more rapidly than the -2.4 power of distance; and (3) both positive and negative contributions to the correlation function are predicted for cosmological models with Omega less than unity.

Calculating Solar Energy Potential of Buildings and Visualization Within Unity 3d Game Engine

NASA Astrophysics Data System (ADS)

Buyuksalih, G.; Bayburt, S.; Baskaraca, A. P.; Karim, H.; Rahman, A. Abdul

2017-10-01

Solar energy modelling is increasingly popular, important, and economic significant in solving energy crisis for big cities. It is a clean and renewable resource of energy that can be utilized to accommodate individual or group of buildings electrical power as well as for indoor heating. Implementing photovoltaic system (PV) in urban areas is one of the best options to solve power crisis over expansion of urban and the growth of population. However, as the spaces for solar panel installation in cities are getting limited nowadays, the available strategic options are only at the rooftop and façade of the building. Thus, accurate information and selecting building with the highest potential solar energy amount collected is essential in energy planning, environmental conservation, and sustainable development of the city. Estimating the solar energy/radiation from rooftop and facade are indeed having a limitation - the shadows from other neighbouring buildings. The implementation of this solar estimation project for Istanbul uses CityGML LoD2-LoD3. The model and analyses were carried out using Unity 3D Game engine with development of several customized tools and functionalities. The results show the estimation of potential solar energy received for the whole area per day, week, month and year thus decision for installing the solar panel could be made. We strongly believe the Unity game engine platform could be utilized for near future 3D mapping visualization purposes.

The New Close Air Support Weapon: Unmanned Combat Aerial Vehicle in 2010 and Beyond.

DTIC Science & Technology

1999-06-04

designing and fielding unmanned aircraft of many types (Reed, 1979, 72). Abruptly halted in 1972, President Richard Nixon suddenly engaged in ddtente...lessons to emerge from the short history of air power is that unity of development and employment is fundamental to air power effectiveness. ( Vallance ... Richard Wilcox. 1996. Strike Star 2025. Air Command and Staff College. Maxwell Air Force Base, Alabama: Air University Press. Cooling, Benjamin Franklin

Towards a New Image of American Indian Women.

ERIC Educational Resources Information Center

Jaimes, Marie Annette

1982-01-01

Examines matriarchy, androgyny, and spiritual unity among men and women from a traditional indigenous world view. Parallels this with brain theory from both Indian and non-Indian perspectives. Asserts that Indian women must reclaim their "power" and strength by finding that source in their traditional past and among their spiritual…

Communication in a Divided World: Opportunities and Constraints.

ERIC Educational Resources Information Center

Lasswell, Harold

Communication systems in a divided world can perpetuate tension and violence or can be instrumental in developing unity. In response to this power, communicators must focus on generating worldwide recognition of interdependence in the shaping and sharing of values. Likewise, a responsible communication policy must stimulate the invention and…

Repositioning Pedagogies and Postcolonialism: Theories, Contradictions and Possibilities

ERIC Educational Resources Information Center

Lavia, Jennifer

2007-01-01

This paper explores the ways in which pedagogies for social inclusion can be informed by the context of postcoloniality. Both "postcolonialism" and "pedagogy" are treated as contentious and ambiguous constructs, yet their unity is to be found in a critical discussion about knowledge, power, culture and politics. In confronting…

TiN Coating of Accelerator Beamline Chambers

NASA Astrophysics Data System (ADS)

Leung, K. N.; Gough, R. A.; Mashaw, A.; Lee, Y.; Wutte, D.

1997-05-01

One of the problems encountered in many high-power rf systems is multipactoring inside vacuum cavities. The potential for multipactoring occurs whenever the secondary electron emission (SEM) coefficient of the surface exceeds unity. The secondary electtron emission coefficient of titanium-nitride is always less than unity. Therefore, a TiN coating can reduce multipactoring and also reduce photoemission electron from beam-pipe surfaces. The TiN film is very stable. A new technique is being explored at LBNL that will allow an efficient way to coat differently shaped surfaces. In this technique, rf-induction discharge with an exposed Ti induction antenna is used. Tests are being performed using argon, nitrogen, and a mixture of argon/nitrogen gases. Results of this testing will be presented.

Unity quantum yield of photogenerated charges and band-like transport in quantum-dot solids.

PubMed

Talgorn, Elise; Gao, Yunan; Aerts, Michiel; Kunneman, Lucas T; Schins, Juleon M; Savenije, T J; van Huis, Marijn A; van der Zant, Herre S J; Houtepen, Arjan J; Siebbeles, Laurens D A

2011-09-25

Solid films of colloidal quantum dots show promise in the manufacture of photodetectors and solar cells. These devices require high yields of photogenerated charges and high carrier mobilities, which are difficult to achieve in quantum-dot films owing to a strong electron-hole interaction and quantum confinement. Here, we show that the quantum yield of photogenerated charges in strongly coupled PbSe quantum-dot films is unity over a large temperature range. At high photoexcitation density, a transition takes place from hopping between localized states to band-like transport. These strongly coupled quantum-dot films have electrical properties that approach those of crystalline bulk semiconductors, while retaining the size tunability and cheap processing properties of colloidal quantum dots.

What do space voyagers value? a thematic analysis of the narratives of spaceflight veterans

NASA Astrophysics Data System (ADS)

Suedfeld, Peter

Values are desired outcomes, differing in importance, that guide people's lives. Considerable anecdotal evidence suggests that astronauts and cosmonauts experience changes in values as a consequence of their experiences in space. Among the most frequently mentioned changes are a greater appreciation of the unity of Earth and humanity, and an increase in self-confidence. Two preliminary studies by the author have confirmed significant changes in values among (a) four Apollo-era American astronauts and (b) ten male astronauts from the Apollo, Mercury, and Gemini programs, three female veterans of the Shuttle-Mir, and two male high-ranking NASA administrators. The current study expanded the database to 104 space veterans from the US, Russia, and other nations, whose narratives (memoirs, media interviews, and oral histories) were subjected to thematic content analysis for references to Schwartz's well-established value categories. Significant pre-flight differences were found related to nationality, space age era (through vs. later than 1975), and longest flight duration. Comparing references from the pre-flight period with those to the time of the mission and then to post-return from space, we found a U-shaped curve for the values of Achievement, Power, and Self-Direction, and steady increases across periods for Enjoyment and Universalism. Compared to multicultural norms, astronauts showed higher values placed on Achievement, Enjoyment (their two primary values), and Power (after the mission only), and lower values on Security, Self-Direction (after the mission), Universalism, and Tradition.

Southern Clerics and the Passing of Lee: Mythic Rhetoric and the Construction of a Sacred Symbol.

ERIC Educational Resources Information Center

Fulmer, Hal W.

1990-01-01

Examines the symbolic content of eulogies delivered by Southern clergymen following the 1870 death of Confederate General Robert E. Lee. Explores the clergy's discussions of Lee's immortality and the redemptive power of audience unity which were foundations for later mythic discourse on the general's life. (SG)

Using Media to Inspire Unity and Citizenship

ERIC Educational Resources Information Center

Parke, Elaine

2005-01-01

Despite the call to come together as community to instill citizenship in youth, there is a powerful educator and community member who does not attend school conferences or sit on community building teams--the mass media. The dynamics of daily living have been transformed by the increasing presence of mass media in daily life. This article…

Sixteen States, One Country: The Political Structure of the Federal Republic of Germany.

ERIC Educational Resources Information Center

Reuter, Konrad

1991-01-01

The relationship between the federal German state ("Bund" or Federation) to the 16 constituent states known as Laender is explored in this document. The first part explains the federal structure; it contains the following sections: (1) Unity in Diversity; (2) Distribution of Responsibility; (3) Legislative Powers; (4)…

Education for Peace.

ERIC Educational Resources Information Center

Clarken, Rodney H.

Peace is one of the greatest needs in the world today. Until the causes of war are addressed, there can be no peace. Education, justice, and unity are the building blocks to peace and the necessary conditions for its existence. Achieving a peaceful world depends upon our willingness and efforts to remove those things that lead to war and to…

Military Critiques of the Current Assessment Process for the Human Domain - An Annotated Bibliography

DTIC Science & Technology

2017-12-05

George Franz, David Pendall, and Jeffrey Steffan, “Host Nation Information Requirements – Achieving Unity of Understanding in Counterinsurgency... Information Dominance Center Fuels Comprehensive Operations,” SIGNAL, April 2010...1 Spell-outs of terms in parentheses: Diplomatic, Information , Military, Economic, Financial, Intelligence and Law Enforcement (DIMEFIL

Is the Tanzanian Ngoni Language Threatened? A Survey of Lexical Borrowing from Swahili

ERIC Educational Resources Information Center

Rosendal, Tove; Mapunda, Gastor

2014-01-01

Tanzania's post-independence language policy has promoted Swahili as a means of achieving national and linguistic unity. This policy has affected the Ngoni language in south-western Tanzania. Today, Swahili has permeated communication all over Tanzania, even in rural and remote areas. This paper discusses lexical borrowing and especially borrowing…

H. G. Wells and Peace Education

ERIC Educational Resources Information Center

Schlichtmann, Klaus

2007-01-01

H. G. Wells produced some of the best literature and practical ideas on peace, providing essential clues for achieving a mutually beneficial federal human unity through an "Open Conspiracy", as he put it, i.e. an intellectual and political transformation, and a revolution in education. It is possible to abolish war and ensure lasting…

The United States and the Indian Constitution.

ERIC Educational Resources Information Center

Weil, Jonathan S.

India, a huge land with the second largest population in the world, socially and economically poor, and culturally and linguistically diverse, became the largest democracy in the world on November 26, 1949 with the adoption of the Indian Constitution. The goals of that constitution are: (1) the achievement of national unity and stability; (2) the…

Photonic lantern adaptive spatial mode control in LMA fiber amplifiers.

PubMed

Montoya, Juan; Aleshire, Chris; Hwang, Christopher; Fontaine, Nicolas K; Velázquez-Benítez, Amado; Martz, Dale H; Fan, T Y; Ripin, Dan

2016-02-22

We demonstrate adaptive-spatial mode control (ASMC) in few-moded double-clad large mode area (LMA) fiber amplifiers by using an all-fiber-based photonic lantern. Three single-mode fiber inputs are used to adaptively inject the appropriate superposition of input modes in a multimode gain fiber to achieve the desired mode at the output. By actively adjusting the relative phase of the single-mode inputs, near-unity coherent combination resulting in a single fundamental mode at the output is achieved.

All optical quantum control of a spin-quantum state and ultrafast transduction into an electric current.

PubMed

Müller, K; Kaldewey, T; Ripszam, R; Wildmann, J S; Bechtold, A; Bichler, M; Koblmüller, G; Abstreiter, G; Finley, J J

2013-01-01

The ability to control and exploit quantum coherence and entanglement drives research across many fields ranging from ultra-cold quantum gases to spin systems in condensed matter. Transcending different physical systems, optical approaches have proven themselves to be particularly powerful, since they profit from the established toolbox of quantum optical techniques, are state-selective, contact-less and can be extremely fast. Here, we demonstrate how a precisely timed sequence of monochromatic ultrafast (~ 2-5 ps) optical pulses, with a well defined polarisation can be used to prepare arbitrary superpositions of exciton spin states in a semiconductor quantum dot, achieve ultrafast control of the spin-wavefunction without an applied magnetic field and make high fidelity read-out the quantum state in an arbitrary basis simply by detecting a strong (~ 2-10 pA) electric current flowing in an external circuit. The results obtained show that the combined quantum state preparation, control and read-out can be performed with a near-unity (≥97%) fidelity.

Winston Solar Concentrators and Evaluation Support. Phase 2: Non-imaging Concentrators for Space Applications

NASA Technical Reports Server (NTRS)

Winston, R.; Ogallagher, J.; Greenman, P.

1978-01-01

A 4.67X, plus or minus 5 deg. compound parabolic concentrator (CPC) for a large photovoltaic array in space was analyzed. The design was demonstrated to be effective in achieving a net power gain which can be varied from more than a factor of 3 down to approximately unity. A method for reducing nonuniformities in illumination to a given desired level was found. The effectiveness of this method, which involves the introduction of a degree of non-specularity in the reflector surface, was confirmed by direct measurements with prepared foil reflectors in a CPC in terrestrial sunshine as well as by computer ray tracing. Further ray tracing confirms that the CPC design is extremely tolerant to pointing and alignment errors, minor distortions, etc. A two stage non-imaging design was shown, by preliminary measurements and analysis, to provide both the desired angular tolerance and the required degree of intensity uniformity if higher concentrations (4X-10X) are necessary.

A class of systolizable IIR digital filters and its design for proper scaling and minimum output roundoff noise

NASA Technical Reports Server (NTRS)

Lei, Shaw-Min; Yao, Kung

1990-01-01

A class of infinite impulse response (IIR) digital filters with a systolizable structure is proposed and its synthesis is investigated. The systolizable structure consists of pipelineable regular modules with local connections and is suitable for VLSI implementation. It is capable of achieving high performance as well as high throughput. This class of filter structure provides certain degrees of freedom that can be used to obtain some desirable properties for the filter. Techniques of evaluating the internal signal powers and the output roundoff noise of the proposed filter structure are developed. Based upon these techniques, a well-scaled IIR digital filter with minimum output roundoff noise is designed using a local optimization approach. The internal signals of all the modes of this filter are scaled to unity in the l2-norm sense. Compared to the Rao-Kailath (1984) orthogonal digital filter and the Gray-Markel (1973) normalized-lattice digital filter, this filter has better scaling properties and lower output roundoff noise.

Improved battery charger for electric vehicles

NASA Technical Reports Server (NTRS)

Rippel, W. E.

1981-01-01

Polyphase version of single-phase "boost chopper" significantly reduces ripple and electromagnetic interference (EMI). Drive circuit of n-phase boost chopper incorporates n-phase duty-cycle generator; inductor, transistor, and diode compose chopper which can run on single-phase or three-phase alternating current or on direct current. Device retains compactness and power factors approaching unity, while improving efficiency.

Len Barton, Critical Education and the Problem of "Decentered Unities"

ERIC Educational Resources Information Center

Apple, Michael W.

2010-01-01

In the process of discussing the significant contributions that Len Barton has made to the sociology of education and to disability studies, I argue that a good deal of critical analyses of power and inequality in education are impoverished by some of their essentialist and reductive tendencies. I use an example taken from disability rights to…

America’s Federal Law Enforcement Future: Achieving Unity of Effort for the Twenty-First Century

DTIC Science & Technology

2012-04-27

Analysis, no. 683 (Washington, DC: CATO Institute, 2011). http://www.cato.org/pubs/pas/PA683.pdf. Seeley , Mark T. "The Goldwater-Nichols Department of...Mark T. Seeley , “The Goldwater - Nichols Department of Defense Act of 1986: Genesis and Postscript,” (Master’s Thesis, Naval Postgraduate School, 1987

ANOPP programming and documentation standards document

NASA Technical Reports Server (NTRS)

1976-01-01

Standards defining the requirements for preparing software for the Aircraft Noise Prediction Program (ANOPP) were given. It is the intent of these standards to provide definition, design, coding, and documentation criteria for the achievement of a unity among ANOPP products. These standards apply to all of ANOPP's standard software system. The standards encompass philosophy as well as techniques and conventions.

Ronald Reagan's Re-formulation of the Rhetoric of War: Analysis of the "Zero Option,""Evil Empire," and "Star Wars" Addresses.

ERIC Educational Resources Information Center

Goodnight, G. Thomas

1986-01-01

Analyzes speeches in which Reagan challenges the following convention: science will continue to create technologically advanced weapons against which no effective defense will be developed, making deterrence through an assured retaliatory capability the only possible defense. Textual analysis reveals how public discourse can achieve unities of…

Unity of elementary particles and forces in higher dimensions.

PubMed

Gogoladze, Ilia; Mimura, Yukihiro; Nandi, S

2003-10-03

The idea of unifying all the gauge and Yukawa forces as well as the gauge, Higgs, and fermionic matter particles naturally leads us to a simple gauge symmetry in higher dimensions with supersymmetry. We present a model in which, for the first time, such a unification is achieved in the framework of quantum field theory.

8 CFR 236.18 - Termination of Family Unity Program benefits.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Termination of Family Unity Program... REMOVED Family Unity Program § 236.18 Termination of Family Unity Program benefits. (a) Grounds for termination. The Service may terminate benefits under the Family Unity Program whenever the necessity for the...

8 CFR 236.18 - Termination of Family Unity Program benefits.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Termination of Family Unity Program... REMOVED Family Unity Program § 236.18 Termination of Family Unity Program benefits. (a) Grounds for termination. The Service may terminate benefits under the Family Unity Program whenever the necessity for the...

Unity PF current-source rectifier based on dynamic trilogic PWM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiao Wang; Boon-Teck Ooi

1993-07-01

One remaining step in perfecting the stand-along, unity power factor, regulated current-source PWM rectifier is to reduce cost, by bringing the 12-valve converter (consisting of three single-phase full bridges that operate with two-level or bilogic PWM) to the six-valve bridge. However, the six-valve topology requires a three-level or trilogic PWM strategy that can handle feedback signals. This feature was not available until now. The paper describes a general method of translating three-phase bilogic PWM signals to three-phase trilogic PWM signals. The method of translation retains the characteristics of the bilogic PWM, including the frequency bandwidth. Experiments show that the trilogicmore » PWM signals produced by the method can not only handle stabilizing feedback signals but also signals for active filtering.« less

Gender as a historical kind: a tale of two genders?

PubMed

Godman, Marion

2018-01-01

Is there anything that members of each binary category of gender have in common? Even many non-essentialists find the lack of unity within a gender worrying as it undermines the basis for a common political agenda for women. One promising proposal for achieving unity is by means of a shared historical lineage of cultural reproduction with past binary models of gender (e.g. Bach in Ethics 122:231-272, 2012). I demonstrate how such an account is likely to take on board different binary and also non-binary systems of gender. This implies that all individuals construed as members of the category, "women" are in fact not members of the same historical kind after all! I then consider different possible means of modifying the account but conclude negatively: the problem runs deeper than has been appreciated thus far.

Testing the non-unity of rate ratio under inverse sampling.

PubMed

Tang, Man-Lai; Liao, Yi Jie; Ng, Hong Keung Tony; Chan, Ping Shing

2007-08-01

Inverse sampling is considered to be a more appropriate sampling scheme than the usual binomial sampling scheme when subjects arrive sequentially, when the underlying response of interest is acute, and when maximum likelihood estimators of some epidemiologic indices are undefined. In this article, we study various statistics for testing non-unity rate ratios in case-control studies under inverse sampling. These include the Wald, unconditional score, likelihood ratio and conditional score statistics. Three methods (the asymptotic, conditional exact, and Mid-P methods) are adopted for P-value calculation. We evaluate the performance of different combinations of test statistics and P-value calculation methods in terms of their empirical sizes and powers via Monte Carlo simulation. In general, asymptotic score and conditional score tests are preferable for their actual type I error rates are well controlled around the pre-chosen nominal level, and their powers are comparatively the largest. The exact version of Wald test is recommended if one wants to control the actual type I error rate at or below the pre-chosen nominal level. If larger power is expected and fluctuation of sizes around the pre-chosen nominal level are allowed, then the Mid-P version of Wald test is a desirable alternative. We illustrate the methodologies with a real example from a heart disease study. (c) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

The Roots of Regional Ambitions

DTIC Science & Technology

1992-12-01

cultural penetration. The colonial powers controlled the military, political, economic and educational activities of the ...almost incomprehensible to the Arabs of Asia. The Nile Valley has sedentary people, while the deserts of Arabia are still home to the Bedouins...own drive them towards the road of organic unity. Yet, as an idea and a symbol it is potent enough to set cultural , even normative, standards

Dielectric Metamaterials

DTIC Science & Technology

2015-05-29

approach to reducing the antenna size and achieving an electrically resistive and magnetically conducting metasurface are shown in (f) and (g...currents generated by the incident radiation. This metasurface can be designed for the chosen compact antenna frequency. 3.3 Polarizer Our...demonstrated near-unity polarization conversion over a 200-nm bandwidth (Figure 18c). However, one drawback of such metasurfaces is that they must operate

Play Selection for High School Theatre: An Opinionated Essay on Some Questions and Controversies

ERIC Educational Resources Information Center

Urice, John K.

2004-01-01

High school theatre productions can have broad beneficial effects. In addition to helping students, they can bring a sense of unity and focus to a school in ways most often associated with higher-profile athletics. The community in which the school resides often benefits from the entertainment and the visible expression of student achievement.…

Influence of Germanium source on dopingless tunnel-FET for improved analog/RF performance

NASA Astrophysics Data System (ADS)

Cecil, Kanchan; Singh, Jawar

2017-01-01

Dopingless (DL) and junctionless devices have attracted attention due to their simplified fabrication process and low thermal budget requirements. Therefore, in this work, we investigated the influence of low band gap Germanium (Ge) instead of Silicon (Si) as a "Source region" material in dopingless (DL) tunnel field-effect transistor (DLTFET). We observed that the Ge source DLTFET delivers much better performance in comparison to Si DLTFET under various analog/RF figure of merits (FOMs), such as transconductance (gm), transconductance generation factor (TGF) (gm /Id), output conductance (gd), output resistance (RO), intrinsic gain (gmRO), intrinsic gate delay (τ) and RF FOMs, like unity gain frequency (fT), gain bandwidth product (GBW) along with various gate capacitances. These parameters were extracted using 2D TCAD device simulations through small signal ac analysis. Higher ION /IOFF ratio (1014) of Ge source DLTFET can reduce the dynamic as well as static power in digital circuits, while higher transconductance generation factor (gm /Id) ∼ 2287 V-1 can lower the bias power of an amplifier. Similarly, enhanced RF FOMs i.e unity gain frequency (fT) and gain bandwidth product (GBW) in Gigahertz range projects the proposed device preference for RF circuits.

Vaporization of a solid surface in an ambient gas

NASA Astrophysics Data System (ADS)

Benilov, M. S.; Jacobsson, S.; Kaddani, A.; Zahrai, S.

2001-07-01

The net flux of vapour from a solid surface in an ambient gas is analysed with the aim to estimate the effect of vaporization cooling on the energy balance of an arc cathode under conditions typical for a high-power current breaker. If the ratio of the equilibrium vapour pressure pv to the ambient pressure p∞ is smaller than unity, the removal of vapour from the surface is due to diffusion into the bulk of the gas. As a consequence, the net flux of the vapour from the surface is much smaller than the emitted flux. An estimate of the diffusion rate under conditions typical for a high-power current breaker indicates that vaporization cooling plays a minor role in the energy balance of the cathode in this case. If ratio pv/p∞ is above unity, the flow of the vapour from the surface appears and the net flux is comparable to the emitted flux. A simple analytical solution has been obtained for this case, which is in a good agreement with results of the Monte Carlo modelling of preceding authors. If pv/p∞ exceeds approximately 4.5, vaporization occurs as into vacuum and the net flux is about 0.82 of the emitted flux.

Luminescence in the fluoride-containing phosphate-based glasses: A possible origin of their high resistance to nanosecond pulse laser-induced damage

PubMed Central

Wang, Pengfei; Lu, Min; Gao, Fei; Guo, Haitao; Xu, Yantao; Hou, Chaoqi; Zhou, Zhiwei; Peng, Bo

2015-01-01

Fusion power offers the prospect of an almost inexhaustible source of energy for future generations. It was reported that fusion fuel gains exceeding unity on the National Ignition Facility (NIF) were achieved, but so far great deal of scientific and engineering challenges have to be overcome for realizing fusion power generation. There is a bottleneck for color-separation gratings in NIF and other similar inertial confinement fusion (ICF) lasers. Here we show a series of high performance phosphate-based glasses that can transmit the third harmonic frequency (3ω) laser light with high efficiency meanwhile filter the fundamental (1ω) and the second harmonic frequency (2ω) laser lights through direct absorption, and especially they exhibit excellent damage threshold induced by nanosecond pulse laser compared with that of the fused silica used in NIF. Yellowish-orange fluorescence emits during the laser-material interaction process, and it can be tailored through regulating the glass structure. Study on its structural origin suggests that the fluorescence emission is a key factor that conduces to the high laser-induced damage resistance of these glasses. The results also indicated the feasibility of utilizing these high performance glasses in novel color separation optics, allowing novel design for the final optics assembly in ICF lasers. PMID:25716328

Luminescence in the fluoride-containing phosphate-based glasses: a possible origin of their high resistance to nanosecond pulse laser-induced damage.

PubMed

Wang, Pengfei; Lu, Min; Gao, Fei; Guo, Haitao; Xu, Yantao; Hou, Chaoqi; Zhou, Zhiwei; Peng, Bo

2015-02-26

Fusion power offers the prospect of an almost inexhaustible source of energy for future generations. It was reported that fusion fuel gains exceeding unity on the National Ignition Facility (NIF) were achieved, but so far great deal of scientific and engineering challenges have to be overcome for realizing fusion power generation. There is a bottleneck for color-separation gratings in NIF and other similar inertial confinement fusion (ICF) lasers. Here we show a series of high performance phosphate-based glasses that can transmit the third harmonic frequency (3ω) laser light with high efficiency meanwhile filter the fundamental (1ω) and the second harmonic frequency (2ω) laser lights through direct absorption, and especially they exhibit excellent damage threshold induced by nanosecond pulse laser compared with that of the fused silica used in NIF. Yellowish-orange fluorescence emits during the laser-material interaction process, and it can be tailored through regulating the glass structure. Study on its structural origin suggests that the fluorescence emission is a key factor that conduces to the high laser-induced damage resistance of these glasses. The results also indicated the feasibility of utilizing these high performance glasses in novel color separation optics, allowing novel design for the final optics assembly in ICF lasers.

Physical constraints, fundamental limits, and optimal locus of operating points for an inverted pendulum based actuated dynamic walker.

PubMed

Patnaik, Lalit; Umanand, Loganathan

2015-10-26

The inverted pendulum is a popular model for describing bipedal dynamic walking. The operating point of the walker can be specified by the combination of initial mid-stance velocity (v0) and step angle (φm) chosen for a given walk. In this paper, using basic mechanics, a framework of physical constraints that limit the choice of operating points is proposed. The constraint lines thus obtained delimit the allowable region of operation of the walker in the v0-φm plane. A given average forward velocity vx,avg can be achieved by several combinations of v0 and φm. Only one of these combinations results in the minimum mechanical power consumption and can be considered the optimum operating point for the given vx,avg. This paper proposes a method for obtaining this optimal operating point based on tangency of the power and velocity contours. Putting together all such operating points for various vx,avg, a family of optimum operating points, called the optimal locus, is obtained. For the energy loss and internal energy models chosen, the optimal locus obtained has a largely constant step angle with increasing speed but tapers off at non-dimensional speeds close to unity.

The Unity connecting module is moved to payload canister

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility, an overhead crane moves the Unity connecting module to the payload canister for transfer to the launch pad. Part of the International Space Station (ISS), Unity is scheduled for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

'To preserve unity while almost allowing for chaos': Testing the aesthetic principle of unity-in-variety in product design.

PubMed

Post, R A G; Blijlevens, J; Hekkert, P

2016-01-01

Unity-in-variety is considered to be one of the oldest-known universal principles of beauty. However, little empirical research exists on how unity and variety together influence aesthetic appreciation. In three studies we investigated how unity and variety predict the aesthetic appreciation of a range of product designs, and further assessed whether perceived visual complexity and individual differences in regulatory focus influence this relationship. Our findings reveal that both unity and variety, while suppressing each other's effect, positively affect aesthetic appreciation. Hence, product designs that exhibit an optimum balance between unity and variety are aesthetically preferred. Furthermore, the research reveals that unity is the dominant factor in this relationship and facilitates the appreciation of variety. We discuss several theoretical and practical implications resulting from these studies. Copyright © 2015 Elsevier B.V. All rights reserved.

Theodor Waitz on psychic unity.

PubMed

Jahoda, Gustav

2014-06-01

The tolerant stance on 'race' by prominent Enlightenment figures was followed in the 19th century by a powerful wave of biological racism. Many of its proponents took the view that human 'races' constitute separate species, and that most non-white ones are of inferior mentality. An early opponent of this claim was James Cowles Prichard, who used mainly missionary reports in seeking to refute it. Far more extensive work was undertaken by the Herbartian psychologist Theodor Waitz, who collected ethnographic material from all over the world. It was published in six volumes - the last two after his death by his former student Georg Gerland. Waitz aim was to demonstrate the 'psychic unity' of mankind. Initially extracts from the volume on African peoples are presented in order to show how he dealt with his material. The main focus is on his first volume entitled Introduction to Anthropology, in which he elaborates his general thesis. In it Waitz maintains, against the biological racists, that mankind is a single species. Furthermore he discusses the changes from savagery to civilization, attributing them to a combination of geography and history. He was followed by Adolf Bastian who, unlike Waitz, was a great traveller with personal experience of peoples all over the globe. Both firmly believed in the psychic unity of mankind, but Bastian's approach to psychology was very different.

KSC-98pc1359

NASA Image and Video Library

1998-10-21

KENNEDY SPACE CENTER, Fla. -- Space Shuttle Endeavour arrives at Launch Pad 39A in the dim early morning light, atop the mobile launcher platform and crawler transporter, after rollout from the Vehicle Assembly Building. The flag identifying the Shuttle (at right) waves slightly from the wind. At left are the Fixed Service Structure and Rotating Service Structure. While at the pad, the orbiter, external tank and solid rocket boosters will undergo final preparations for the STS-88 launch targeted for Dec. 3, 1998. Mission STS-88 is the first U.S. flight for the assembly of the International Space Station and will carry the Unity connecting module. While on orbit, the flight crew will deploy Unity from the payload bay and connect it to the Russian-built Zarya control module which will be in orbit at that time. Unity will be the main connecting point for later U.S. station modules and components. More than 40 launches are planned over five years involving the resources and expertise of 16 cooperating nations. Comprising the STS-88 crew are Commander Robert D. Cabana, Pilot Frederick W. "Rick" Sturckow, Mission Specialists Nancy J. Currie, Jerry L. Ross, James H. Newman and Russian cosmonaut Sergei Konstantinovich Krikalev. Ross and Newman will make three spacewalks to connect power, data and utility lines and install exterior equipment

Unity nameplate is attached to module for ISS and Mission STS-88

NASA Technical Reports Server (NTRS)

1998-01-01

- In the Space Station Processing Facility, a worker checks placement of the nameplate to be attached to the Unity connecting module, part of the International Space Station. Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

Unity nameplate added to module for ISS and Mission STS-88

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility, workers look over the Unity connecting module, part of the International Space Station, after attaching the nameplate. Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

The Unity connecting module is moved to payload canister

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility, workers at the side and on the floor of the payload canister guide the Unity connecting module into position for transfer to the launch pad. Part of the International Space Station (ISS), Unity is scheduled for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

Unity nameplate examined after being attached to module for ISS and Mission STS-88

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility, a worker checks placement of the nameplate for the Unity connecting module, part of the International Space Station. Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

Unity nameplate is attached to module for ISS and Mission STS-88

NASA Technical Reports Server (NTRS)

1998-01-01

- In the Space Station Processing Facility, a worker places the nameplate on the side of the Unity connecting module, part of the International Space Station. Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

The Unity connecting module is moved to payload canister

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility, workers attach the overhead crane that will lift the Unity connecting module from its workstand to move the module to the payload canister. Part of the International Space Station (ISS), Unity is scheduled for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

The Unity connecting module is moved to payload canister

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility, a closeup view shows the overhead crane holding the Unity connecting module as it moves it to the payload canister for transfer to the launch pad. Part of the International Space Station (ISS), Unity is scheduled for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

Variation of Zipf's exponent in one hundred live languages: A study of the Holy Bible translations

NASA Astrophysics Data System (ADS)

Mehri, Ali; Jamaati, Maryam

2017-08-01

Zipf's law, as a power-law regularity, confirms long-range correlations between the elements in natural and artificial systems. In this article, this law is evaluated for one hundred live languages. We calculate Zipf's exponent for translations of the holy Bible to several languages, for this purpose. The results show that, the average of Zipf's exponent in studied texts is slightly above unity. All studied languages in some families have Zipf's exponent lower/higher than unity. It seems that geographical distribution impresses the communication between speakers of different languages in a language family, and affect similarity between their Zipf's exponent. The Bible has unique concept regardless of its language, but the discrepancy in grammatical rules and syntactic regularities in applying stop words to make sentences and imply a certain concept, lead to difference in Zipf's exponent for various languages.

Small slot waveguide rings for on-chip quantum optical circuits.

PubMed

Rotenberg, Nir; Türschmann, Pierre; Haakh, Harald R; Martin-Cano, Diego; Götzinger, Stephan; Sandoghdar, Vahid

2017-03-06

Nanophotonic interfaces between single emitters and light promise to enable new quantum optical technologies. Here, we use a combination of finite element simulations and analytic quantum theory to investigate the interaction of various quantum emitters with slot-waveguide rings. We predict that for rings with radii as small as 1.44 μm, with a Q-factor of 27,900, near-unity emitter-waveguide coupling efficiencies and emission enhancements on the order of 1300 can be achieved. By tuning the ring geometry or introducing losses, we show that realistic emitter-ring systems can be made to be either weakly or strongly coupled, so that we can observe Rabi oscillations in the decay dynamics even for micron-sized rings. Moreover, we demonstrate that slot waveguide rings can be used to directionally couple emission, again with near-unity efficiency. Our results pave the way for integrated solid-state quantum circuits involving various emitters.

Magnetics and Power System Upgrades for the Pegasus-U Experiment

NASA Astrophysics Data System (ADS)

Preston, R. C.; Bongard, M. W.; Fonck, R. J.; Lewicki, B. T.

2014-10-01

To support the missions of developing local helicity injection startup and exploiting advanced tokamak physics studies at near unity aspect ratio, the proposed Pegasus-U will include expanded magnetic systems and associated power supplies. A new centerstack increases the toroidal field seven times to 1 T and the volt-seconds by a factor of six while maintaining operation at an aspect ratio of 1.2. The poloidal field magnet system is expanded to support improved shape control and robust double or single null divertor operation at the full plasma current of 0.3 MA. An integrated digital control system based on Field Programmable Gate Arrays (FPGAs) provides active feedback control of all magnet currents. Implementation of the FPGAs is achieved with modular noise reducing electronics. The digital feedback controllers replace the existing analog systems and switch multiplexing technology. This will reduce noise sensitivity and allow the operational Ohmic power supply voltage to increase from 2100 V to its maximum capacity of 2400 V. The feedback controller replacement also allows frequency control for ``freewheeling''--stopping the switching for a short interval and allowing the current to coast. The FPGAs assist in optimizing pulse length by having programmable switching events to minimize energy losses. They also allow for more efficient switching topologies that provide improved stored energy utilization, and support increasing the pulse length from 25 ms to 50-100 ms. Work supported by US DOE Grant DE-FG02-96ER54375.

Aircraft and Engine Development Testing

DTIC Science & Technology

1986-09-01

Control in Flight * Integrated Inlet- engine * Power/weight Exceeds Unity F-lll * Advanced Engines * Augmented Turbofan * High Turbine Temperature...residence times). Also, fabrication of a small scale "hot" engine with rotating components such as compressors and turbines with cooled blades , is...capabil- ities are essential to meet the needs of current and projected aircraft and engine programs. The required free jet nozzles should be capable of

JPRS Report, Science & Technology, China: Energy

DTIC Science & Technology

1991-08-23

restriction. Unity push forward. Category 2 should be stabilized and of understanding is essential for promoting reform in improved. Category 3 should be...Consultative Council, everyone wasindustrial policy change, which pays more attention to extremely concerned about the situation at the Three ecnomic ...is essential for spurring economic growth As for the question of power transmission, preliminary in the region. This first of all requires development

The Adequacy of Current Interagency Doctrine

DTIC Science & Technology

2007-06-15

proposed new initiatives, the CSIS model calls for the establishment of an Interagency Task Force ( IATF ) to achieve unity of effort at the tactical...level, specifically 15 for reconstruction and stability operations. The IATF would assume the lead from the COCOM once major combat operations were...complete in a given area or region. The IATF would be civilian-led, directly control full interagency resources, and have dedicated funding authority

How Can We Best Achieve Contracting Unity of Effort in the CENTCOM Area of Responsibility?

DTIC Science & Technology

2013-12-01

3  2.  Literature Review ................................................................................3  3.  Interview Design and...2010, JCC-I/A was re- designated as the Central Command Joint Theater Support Contracting Command (C-JTSCC). Although the military has used...provision of integrated contracted support and management of contractor personnel providing that support to the joint force in a designated operational

Has the Sun Set on Quantum Dot-Sensitized Solar Cells?

DOE PAGES

Wrenn, Toshia L.; McBride, James R.; Smith, Nathanael J.; ...

2015-01-01

This is a reminder, a review and a look toward the future prospects for quantum dot-sensitized solar cells - a reminder of the highly viable, energy-efficient solar cells achievable. This is also a review of ground-breaking devices and their similarities to the near unity photon-to-electron mechanisms of photosynthesis; a look toward architectures that capitalize on the advances observed in previous work.

The Activity-Based Approach to Achieving Theoretical and Practical Consensus in Pedagogy of N. F. Talyzina

ERIC Educational Resources Information Center

Chapaev, Nikolay K.; Akimova, Olga B.; Selivanov, Andrey V.; Shaforostova, Tatiana V.

2016-01-01

The relevance of the problem under study is based on the necessity to solve the permanent problem of the unity of theory and practice in the content of students' cognitive activity in the modern conditions. The purpose of the article is to analyze and to generalize the main concepts of pedagogy by N.F. Talyzina for implementation of the…

Making the Dream Real: Montana's Indian Education for All Initiative Thrives in a National Climate of Anti-Ethnic Studies

ERIC Educational Resources Information Center

Carjuzaa, Jioanna; Baldwin, Anna E; Munson, Michael

2015-01-01

The espoused foundation of U.S. society, "E pluribus unum" (out of many, one), is based on the belief that this nation should simultaneously support pluralism and promote unity. The road to making this ideal a reality, however, has not always been smooth. The ever-widening achievement gap highlights how this discordance plays out in our…

Unity nameplate gets final check before being attached to module for ISS and Mission STS-88

NASA Technical Reports Server (NTRS)

1998-01-01

- In the Space Station Processing Facility, workers make a final check of the nameplate to be attached to the Unity connecting module, part of the International Space Station. Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

Unity nameplate examined after being attached to module for ISS and Mission STS-88

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility, Joan Higgenbotham, with KSC's Astronaut Office Computer Support, checks placement of the nameplate for the Unity connecting module, part of the International Space Station. Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

The Unity connecting module moves into payload bay of Endeavour

NASA Technical Reports Server (NTRS)

1998-01-01

The Unity connecting module is moved toward the payload bay of the orbiter Endeavour at Launch Pad 39A. Part of the International Space Station (ISS), Unity is scheduled for launch Dec. 3, 1998, on Mission STS-88 . The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach it to the Russian-built Zarya control module which will be in orbit at that time.

KSC-98pc1411

NASA Image and Video Library

1998-10-22

In the Space Station Processing Facility, an overhead crane moves the Unity connecting module to the payload canister for transfer to the launch pad. Part of the International Space Station (ISS), Unity is scheduled for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time

Unity nameplate examined before being attached to module for ISS and Mission STS-88

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility, holding the nameplate for the Unity connecting module are (left) Joan Higginbotham, with the Astronaut Office Computer Support Branch, and (right) Nancy Tolliver, with Boeing-Huntsville. Part of the International Space Station, Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

Unity connecting module in SSPF

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility, the Unity connecting module, part of the International Space Station, is shown with Pressurized Mating Adapters 1 (left) and 2 (right) attached. Unity is scheduled to undergo testing of the common berthing mechanism to which other space station elements will dock. Unity is the primary payload on mission STS-88, targeted to launch Dec. 3, 1998. Other testing includes the Pad Demonstration Test to verify the compatibility of the module with the Space Shuttle as well as the ability of the astronauts to send and receive commands to Unity from the flight deck of the orbiter. Unity is expected to be ready for installation into the payload canister on Oct. 25, and transported to Launch Pad 39-A on Oct. 27. The Unity will be mated to the Russian-built Zarya control module which should already be in orbit at that time.

8 CFR 245a.37 - Termination of Family Unity Program benefits.

Code of Federal Regulations, 2012 CFR

2012-01-01

... or her ineligible for Family Unity benefits under the LIFE Act Amendments; (3) The alien, upon whose...) A qualifying relationship to the alien, upon whose status Family Unity benefits under the LIFE Act... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Termination of Family Unity Program...

8 CFR 245a.37 - Termination of Family Unity Program benefits.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) The alien, upon whose status Family Unity benefits under the LIFE Act were based, fails to apply for... Unity benefits under the LIFE Act Amendments shall render the alien amenable to removal under any ground... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Termination of Family Unity Program...

8 CFR 245a.37 - Termination of Family Unity Program benefits.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) The alien, upon whose status Family Unity benefits under the LIFE Act were based, fails to apply for... Unity benefits under the LIFE Act Amendments shall render the alien amenable to removal under any ground... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Termination of Family Unity Program...

8 CFR 245a.37 - Termination of Family Unity Program benefits.

Code of Federal Regulations, 2013 CFR

2013-01-01

... or her ineligible for Family Unity benefits under the LIFE Act Amendments; (3) The alien, upon whose...) A qualifying relationship to the alien, upon whose status Family Unity benefits under the LIFE Act... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Termination of Family Unity Program...

8 CFR 245a.37 - Termination of Family Unity Program benefits.

Code of Federal Regulations, 2014 CFR

2014-01-01

... or her ineligible for Family Unity benefits under the LIFE Act Amendments; (3) The alien, upon whose...) A qualifying relationship to the alien, upon whose status Family Unity benefits under the LIFE Act... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Termination of Family Unity Program...

An algorithm for the design and tuning of RF accelerating structures with variable cell lengths

NASA Astrophysics Data System (ADS)

Lal, Shankar; Pant, K. K.

2018-05-01

An algorithm is proposed for the design of a π mode standing wave buncher structure with variable cell lengths. It employs a two-parameter, multi-step approach for the design of the structure with desired resonant frequency and field flatness. The algorithm, along with analytical scaling laws for the design of the RF power coupling slot, makes it possible to accurately design the structure employing a freely available electromagnetic code like SUPERFISH. To compensate for machining errors, a tuning method has been devised to achieve desired RF parameters for the structure, which has been qualified by the successful tuning of a 7-cell buncher to π mode frequency of 2856 MHz with field flatness <3% and RF coupling coefficient close to unity. The proposed design algorithm and tuning method have demonstrated the feasibility of developing an S-band accelerating structure for desired RF parameters with a relatively relaxed machining tolerance of ∼ 25 μm. This paper discusses the algorithm for the design and tuning of an RF accelerating structure with variable cell lengths.

Prospects for Alpha Particle Heating in JET in the Hot Ion Regime

NASA Astrophysics Data System (ADS)

Cordey, J. G.; Keilhacker, M.; Watkins, M. L.

1987-01-01

The prospects for alpha particle heating in JET are discussed. A computational model is developed to represent adequately the neutron yield from JET plasmas heated by neutral beam injection. This neutral beam model, augmented by a simple plasma model, is then used to determine the neutron yields and fusion Q-values anticipated for different heating schemes in future operation of JET with tritium. The relative importance of beam-thermal and thermal-thermal reactions is pointed out and the dependence of the results on, for example, plasma density, temperature, energy confinement and purity is shown. Full 1½-D transport code calculations, based on models developed for ohmic, ICRF and NBI heated JET discharges, are used also to provide a power scan for JET operation in tritium in the low density, high ion temperature regime. The results are shown to be in good agreement with the estimates made using the simple plasma model and indicate that, based on present knowledge, a fusion Q-value in the plasma centre above unity should be achieved in JET.

Improved Fibrinolysis Using Magnetically Driven Colloidal Microwheels

NASA Astrophysics Data System (ADS)

Disharoon, Dante; Tasci, Onur; Schoeman, Rogier; Rana, Kuldeepsinh; Herson, Paco; Marr, David; Neeves, Keith

2017-11-01

At the microscale, fluid dynamics are unique because viscous forces dominate over inertial forces, with Reynolds numbers typically less than unity. To move through microscale channels (order 100 μ m) over macroscale distances (>1 cm) devices based on cellular machinery have been developed, but they are slow and difficult to implement within in vivo environments. To address these issues, we report the assembly and translation of magnetically-powered colloidal microwheels (μ wheels) capable of translation at speeds of over 100 μ m/s. In this, superparamagnetic microparticles cluster into wheel-like shapes that spin when subject to an order milliTesla planar rotating magnetic field. By exploiting wet friction between μ wheels and adjacent surfaces, not only can significant μ wheel translation speeds be achieved but also travel direction can be precisely and rapidly controlled. With both assembly and translation manipulated via non-gradient external magnetic fields that do not attenuate in tissue, this method is well-suited for drug delivery. We demonstrate this by showing that μ wheels functionalized with fibrinolytics can dissolve blood clots five-fold faster than soluble fibrinolytics at therapeutic concentrations.

Cybernetic prosthesis

NASA Technical Reports Server (NTRS)

Mann, R. W.

1974-01-01

Design and development of a prosthetic device fitted to an above elbow amputee is reported that derives control information from the human to modulate power to an actuator to drive the substitute limb. In turn, the artificial limb generates sensory information feedback to the human nervous system and brain. This synergetic unity feeds efferent or motor control information from the human to the machine, and the machine responds, delivering afferent or sensory information back to the man.

Potential of Iraqi Local Councils to facilitate Iraqi National Unity

DTIC Science & Technology

2009-06-12

U.S. forces to form a multi-tribal grassroots council involving both sects. Abu Ahmed currently serves as a local contractor in Baghdad. He has...worked with local councils and supported their efforts in reconstruction. Abu Ahmed offers insight into local councils from a unique third...responded on average in agreement when asked whether reform was more effective if local leaders sought to achieve it. Abu Ahmed , a prominent

USSR Report, Political and Sociological Affairs

DTIC Science & Technology

1984-05-08

Organization of African Unity on proclaiming Africa a nuclear- free zone, the active anti-war and anti-Imperialist stand assumed by the conference of ministers...prevention of outer space militar- ization, ist the disbandment of military alliances, for proclaiming Canada a zone free -from nuclear weapons and for...achieve an abolition of all the formalities existing now which prevent a " free " exchange between governments and various social orders. They said let

Achieving Unity of Effort: A Challenge in Domestic Support Operations.

DTIC Science & Technology

1998-03-09

active duty soldiers and 13,376 National Guard soldiers from 47 states and territories in support of the Olympic and Paralympic Games . There was no...Olympic and Paralympic Games Contingency Operations," presented at the DOD Emergency Preparedness Course 97-01,1 Nov 97. Hereafter cited as Steinmetz...Preparedness Course. 63 Shalikashvili, 1-3. 64 FORSCOM 1996 Olympic and Paralympic Games Operations Plan for Emergency Contingency Support, Ft

Improving Interagency Coordination and Unity of Effort: An Organizational Analysis of the Contemporary Provincial Reconstruction Team

DTIC Science & Technology

2010-05-20

capability. A DOS PRT member, Linda Specht , recalls that: The contemporary PRT hierarchical organization achieves such integration and accountability...Linda Specht , 4 February 2008" (Fort Leavenworth, Kansas: Combat Studies Institute, 2008), 9, http://comarms.ipac.dynixasp.com/ipac20/ipac. jsp...term=interview+with+linda+ specht &index=.GW#focus (accessed February 10, 2010). Figure 2 represents the cross-functional contemporary PRT organization

37 CFR 1.499 - Unity of invention during the national stage.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Unity of invention during the... Provisions National Stage § 1.499 Unity of invention during the national stage. If the examiner finds that a national stage application lacks unity of invention under § 1.475, the examiner may in an Office action...

The Unity connecting module moves into payload bay of Endeavour

NASA Technical Reports Server (NTRS)

1998-01-01

Looking like a painting, this wide-angle view shows the Unity connecting module being moved toward the payload bay of the orbiter Endeavour at Launch Pad 39A. Part of the International Space Station (ISS), Unity is scheduled for launch Dec. 3, 1998, on Mission STS-88. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach it to the Russian-built Zarya control module which will be in orbit at that time.

The Unity connecting module moves into payload bay of Endeavour

NASA Technical Reports Server (NTRS)

1998-01-01

Viewed from below, the Unity connecting module is moved into the payload bay of the orbiter Endeavour at Launch Pad 39A. Part of the International Space Station (ISS), Unity is scheduled for launch Dec. 3, 1998, on Mission STS-88. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach it to the Russian-built Zarya control module which will be in orbit at that time.

KSC-98pc1363

NASA Image and Video Library

1998-10-22

In the Space Station Processing Facility, a worker checks placement of the nameplate for the Unity connecting module, part of the International Space Station. Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time

KSC-98pc1367

NASA Image and Video Library

1998-10-22

In the Space Station Processing Facility, a worker checks placement of the nameplate to be attached to the Unity connecting module, part of the International Space Station. Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time

KSC-98pc1410

NASA Image and Video Library

1998-10-22

In the Space Station Processing Facility, workers attach the overhead crane that will lift the Unity connecting module from its workstand to move the module to the payload canister. Part of the International Space Station (ISS), Unity is scheduled for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time

KSC-98pc1365

NASA Image and Video Library

1998-10-22

In the Space Station Processing Facility, workers look over the Unity connecting module, part of the International Space Station, after attaching the nameplate. Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time

KSC-98pc1366

NASA Image and Video Library

1998-10-22

In the Space Station Processing Facility, workers make a final check of the nameplate to be attached to the Unity connecting module, part of the International Space Station. Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time

KSC-98pc1412

NASA Image and Video Library

1998-10-22

In the Space Station Processing Facility, a closeup view shows the overhead crane holding the Unity connecting module as it moves it to the payload canister for transfer to the launch pad. Part of the International Space Station (ISS), Unity is scheduled for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time

KSC-98pc1413

NASA Image and Video Library

1998-10-22

In the Space Station Processing Facility, workers at the side and on the floor of the payload canister guide the Unity connecting module into position for transfer to the launch pad. Part of the International Space Station (ISS), Unity is scheduled for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time

Unity nameplate examined before being attached to module for ISS and Mission STS-88

NASA Technical Reports Server (NTRS)

1998-01-01

Examining the nameplate for the Unity connecting module, in the Space Station Processing Facility, are (left to right) Joe Schweiger and Tommy Annis, of Boeing-KSC, and Nancy Tolliver, of Boeing-Huntsville. An unidentified worker behind them looks on. Part of the International Space Station, Unity was expected to be transported to Launch Pad 39A on Oct. 26 for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

KSC-98pc1358

NASA Image and Video Library

1998-10-21

KENNEDY SPACE CENTER, Fla. -- Towering atop the mobile launcher platform and crawler transporter in the early morning light, Space Shuttle Endeavour arrives at Launch Pad 39A after rollout from the Vehicle Assembly Building. At its left are the Rotating Service Structure and the Fixed Service Structure; at the right is the 300,000-gallon water tank, part of the sound suppression water system. While at the pad, the orbiter, external tank and solid rocket boosters will undergo final preparations for the STS-88 launch targeted for Dec. 3, 1998. Mission STS-88 is the first U.S. flight for the assembly of the International Space Station and will carry the Unity connecting module. While on orbit, the flight crew will deploy Unity from the payload bay and connect it to the Russian-built Zarya control module which will be in orbit at that time. Unity will be the main connecting point for later U.S. station modules and components. More than 40 launches are planned over five years involving the resources and expertise of 16 cooperating nations. Comprising the STS-88 crew are Commander Robert D. Cabana, Pilot Frederick W. "Rick" Sturckow, Mission Specialists Nancy J. Currie, Jerry L. Ross, James H. Newman and Russian cosmonaut Sergei Konstantinovich Krikalev. Ross and Newman will make three spacewalks to connect power, data and utility lines and install exterior equipment

Managing Complexity - Developing the Node Control Software For The International Space Station

NASA Technical Reports Server (NTRS)

Wood, Donald B.

2000-01-01

On December 4th, 1998 at 3:36 AM STS-88 (the space shuttle Endeavor) was launched with the "Node 1 Unity Module" in its payload bay. After working on the Space Station program for a very long time, that launch was one of the most beautiful sights I had ever seen! As the Shuttle proceeded to rendezvous with the Russian American module know as Zarya, I returned to Houston quickly to start monitoring the activation of the software I had spent the last 3 years working on. The FGB module (also known as "Zarya"), was grappled by the shuttle robotic arm, and connected to the Unity module. Crewmembers then hooked up the power and data connections between Zarya and Unity. On December 7th, 1998 at 9:49 PM CST the Node Control Software was activated. On December 15th, 1998, the Node-l/Zarya "cornerstone" of the International Space Station was left on-orbit. The Node Control Software (NCS) is the first software flown by NASA for the International Space Station (ISS). The ISS Program is considered the most complex international engineering effort ever undertaken. At last count some 18 countries are active partners in this global venture. NCS has performed all of its intended functions on orbit, over 200 miles above us. I'll be describing how we built the NCS software.

Source-drain burnout mechanism of GaAs power MESFETS: Three terminal effects

NASA Astrophysics Data System (ADS)

Takamiya, Saburo; Sonoda, Takuji; Yamanouchi, Masahide; Fujioka, Takashi; Kohno, Masaki

1997-03-01

Theoretical expressions for thermal and electrical feedback effects are derived. These limit the power capability of a power FET and lead a device to catastrophic breakdown (source-drain burnout) when the loop gain of the former reaches unity. Field emission of thermally excited electrons at the Schottky gate plays the key role in thermal feedback, while holes being impact ionized by the drain current play a similar role in the electrical feedback. Thermal feedback is dominant in a high temperature and low drain voltage area. Electrical feedback is dominant in a high drain voltage and low temperature area. In the first area, a high junction temperature is the main factor causing the thermal runaway of the device. In the second area, the electrcal feedback increases the drain current and the temperature and gives a trigger to the thermal feedback so that it reaches unity more easily. Both effects become significant in proportion to transconductance and gate bias resistance, and cause simultaneous runaway of the gate and drain currents. The expressions of the loop gains clearly indicate the safe operating conditions for a power FET. C-band 4 W (1 chip) and 16 W (4 chip) GaAs MESFETs were used as the experimental samples. With these devices the simultaneous runaway of the gate and the drain currents, apparent dependence of the three teminal breakdown voltage on the gate bias resistance in the region dominated by electrical feedback, the rapid increase of the field emitted current at the critical temperature and clear coincidence between the measured and calculated three terminal gate currents both in the thermal feedback dominant region, etc. are demonstrated. The theory explains the experimental results well.

Cascaded H-bridge multilevel inverter for renewable energy generation

NASA Astrophysics Data System (ADS)

Pandey, Ravikant; Nath Tripathi, Ravi; Hanamoto, Tsuyoshi

2016-04-01

In this paper cascaded H-bridge multilevel inverter (CHBMLI) has been investigated for the application of renewable energy generation. Energy sources like solar, wind, hydro, biomass or combination of these can be manipulated to obtain alternative sources for renewable energy generation. These renewable energy sources have different electrical characteristics like DC or AC level so it is challenging to use generated power by connecting to grid or load directly. The renewable energy source require specific power electronics converter as an interface for conditioning generated power .The multilevel inverter can be utilized for renewable energy sources in two different modes, the power generation mode (stand-alone mode), and compensator mode (statcom). The performance of the multilevel inverter has been compared with two level inverter. In power generation mode CHBMLI supplies the active and reactive power required by the different loads. For operation in compensator mode the indirect current control based on synchronous reference frame theory (SRFT) ensures the grid operating in unity power factor and compensate harmonics and reactive power.

Induced Power of the Helicopter Rotor

NASA Technical Reports Server (NTRS)

Ormiston, Robert A.

2004-01-01

A simplified rotor model was used to explore fundamental behavior of lifting rotor induced power at moderate and high advance ratios. Several rotor inflow theories, including dynamic inflow theory and prescribed-wake vortex theory, together with idealized notional airfoil stall models were employed. A number of unusual results were encountered at high advance ratios including trim control reversal and multiple trim solutions. Significant increases in rotor induced power (torque) above the ideal minimum were observed for moderately high advance ratio. Very high induced power was observed near and above unity advance ratio. The results were sensitive to the stall characteristics of the airfoil models used. An equivalent wing analysis was developed to determine induced power from Prandtl lifting line theory and help interpret the rotor induced power behavior in terms of the spanwise airload distribution. The equivalent wing approach was successful in capturing the principal variations of induced power for different configurations and operating conditions. The effects blade root cutout were found to have a significant effect on rotor trim and induced power at high advance ratios.

Bi-directional power control system for voltage converter

DOEpatents

Garrigan, Neil Richard; King, Robert Dean; Schwartz, James Edward

1999-01-01

A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals.

Bi-directional power control system for voltage converter

DOEpatents

Garrigan, N.R.; King, R.D.; Schwartz, J.E.

1999-05-11

A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals. 10 figs.

The STTI Practice-Academe Innovative Collaboration Award: honoring innovation, partnership, and excellence.

PubMed

Kirschling, Jane Marie; Erickson, Jeanette Ives

2010-09-01

To describe the benefits and barriers associated with practice-academe partnerships and introduce Sigma Theta Tau International's (STTI's) Practice-Academe Innovative Collaboration Award and the 2009 award recipients. In 2008, STTI created the CNO-Dean Advisory Council and charged it with reviewing the state of practice-academe collaborations and developing strategies for optimizing how chief nursing officers (CNOs) and deans work together to advance the profession and discipline of nursing. The Council, in turn, developed the Practice-Academe Innovative Collaboration Award to encourage collaboration across sectors, recognize innovative collaborative efforts, and spotlight best practices. A call for award submissions resulted in 24 applications from around the globe. An award winner and seven initiatives receiving honorable mentions were selected. The winning initiatives reflect innovative academe-service partnerships that advance evidence-based practice, nursing education, nursing research, and patient care. The proposals were distinguished by their collaborators' shared vision and unity of purpose, ability to leverage strengths and resources, and willingness to recognize opportunities and take risks. By partnering with one another, nurses in academe and in service settings can directly impact nursing education and practice, often effecting changes and achieving outcomes that are more extensive and powerful than could be achieved by working alone. The award-winning initiatives represent best practices for bridging the practice-academe divide and can serve as guides for nurse leaders in both settings.

A New Control Method to Mitigate Power Fluctuations for Grid Integrated PV/Wind Hybrid Power System Using Ultracapacitors

NASA Astrophysics Data System (ADS)

Jayalakshmi, N. S.; Gaonkar, D. N.

2016-08-01

The output power obtained from solar-wind hybrid system fluctuates with changes in weather conditions. These power fluctuations cause adverse effects on the voltage, frequency and transient stability of the utility grid. In this paper, a control method is presented for power smoothing of grid integrated PV/wind hybrid system using ultracapacitors in a DC coupled structure. The power fluctuations of hybrid system are mitigated and smoothed power is supplied to the utility grid. In this work both photovoltaic (PV) panels and the wind generator are controlled to operate at their maximum power point. The grid side inverter control strategy presented in this paper maintains DC link voltage constant while injecting power to the grid at unity power factor considering different operating conditions. Actual solar irradiation and wind speed data are used in this study to evaluate the performance of the developed system using MATLAB/Simulink software. The simulation results show that output power fluctuations of solar-wind hybrid system can be significantly mitigated using the ultracapacitor based storage system.

Design parameters of a resonant infrared photoconductor with unity quantum efficiency

NASA Technical Reports Server (NTRS)

Farhoomand, Jam; Mcmurray, Robert E., Jr.

1991-01-01

This paper proposes a concept of a resonant infrared photoconductor that has characteristics of 100 percent quantum efficiency, high photoconductive gain, and very low noise equivalent power. Central to this concept is an establishment of a high-finesse absorption cavity internal to the detector element. A theoretical analysis is carried out, demonstrating this concept and providing some design guidelines. A Ge:Ga FIR detector is presently being fabricated using this approach.

FIRE's Guide to First-Year Orientation and Thought Reform on Campus. FIRE's Guides to Student Rights on Campus

ERIC Educational Resources Information Center

Silverglate, Harvey A.; Lorence, Jordan

2005-01-01

Before one can have the freedom to express ideas in open debate, however, one must have freedom of conscience: the right to arrive at one's private beliefs, without being coerced into an artificial unity by those who wield power over him/her. After all, the freedom to speak is a dead letter if one lacks the freedom to think, to believe, or to…

The effect of beam pre-bunching on the excitation of terahertz plasmons in a parallel plane guiding system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, Suresh C.; Malik, Pratibha

2015-04-15

The excitation of terahertz (THz) plasmons by a pre-bunched relativistic electron beam propagating in a parallel plane semiconducting guiding system is studied. It is found that the n-InSb semiconductor strongly supports the confined surface plasmons in the terahertz frequency range. The growth rate and efficiency of the THz surface plasmons increase linearly with modulation index and show the largest value as modulation index approaches unity. Moreover, the growth rate of the instability scales as one-third power of the beam density and inverse one-third power of the THz radiation frequency.

Universal statistics of the knockout tournament

NASA Astrophysics Data System (ADS)

Baek, Seung Ki; Yi, Il Gu; Park, Hye Jin; Kim, Beom Jun

2013-11-01

We study statistics of the knockout tournament, where only the winner of a fixture progresses to the next. We assign a real number called competitiveness to each contestant and find that the resulting distribution of prize money follows a power law with an exponent close to unity if the competitiveness is a stable quantity and a decisive factor to win a match. Otherwise, the distribution is found narrow. The existing observation of power law distributions in various kinds of real sports tournaments therefore suggests that the rules of those games are constructed in such a way that it is possible to understand the games in terms of the contestants' inherent characteristics of competitiveness.

Achieving National Unity of Effort in Cyber

DTIC Science & Technology

2011-06-16

Congress (pp. 309-364). Carlisle, PA: Strategic Studies Institute, U.S. Army War College. 6 Muniz, J. J. (2009). Declawing the Dragon : Why the U.S...12 Muniz, J. J. (2009). Declawing the Dragon : Why the U.S. Must Counter Chinese Cyber-Warriors. Fort Leavenworth, KS: U.S. Army Command and General...Minister. (2010). A Strong Britian in an Age of Uncertainty: The National Security Strategy. London, England. 28 Yesui, Z . (2010). China’s Concept

Practicing What You Preach: Achieving Unity of Effort and Unified Action During Domestic Response Operations

DTIC Science & Technology

2007-05-10

planners will also benefit from experiencing the regimented military decision - making process and working with experienced operational planners. This...picture of the disaster area for the senior decision -makers, duplication of efforts, gaps in addressing requests for assistance, and the inefficient...Guard Atlantic Area. Interview by author, 25 March 2007. Mr. Doane stated that the JTF operated “in a vacuum” and “outside the inter-agency decision

USSR Report: Political and Sociological Affairs, No. 1474

DTIC Science & Technology

1983-11-09

people of our country now have cinematic art, which is created by the masters of socialist culture; its importance in the ideological, moral and...young people. The history of our cinematic art is a living manuscript of national achieve- ments in the revolutionary transformation of the life and...unity of the Marxist-Leninist philosophy of the artists and with the develop- ment in the channel of socialist realism in which each national

Unity connecting module placed in new site in SSPF

NASA Technical Reports Server (NTRS)

1998-01-01

The Unity connecting module, part of the International Space Station, is placed in a work station in the Space Station Processing Facility (SSPF). As the primary payload on mission STS-88, scheduled to launch Dec. 3, 1998, Unity will be mated to the Russian-built Zarya control module which should already be in orbit at that time. In the SSPF, Unity is undergoing testing such as the Pad Demonstration Test to verify the compatibility of the module with the Space Shuttle, as well as the ability of the astronauts to send and receive commands to Unity from the flight deck of the orbiter, and the common berthing mechanism to which other space station elements will dock. Unity is expected to be ready for installation into the Shuttle's payload canister on Oct. 25, and transported to Launch Pad 39-A on Oct. 27.

Simple piezoelectric-actuated mirror with 180 kHz servo bandwidth.

PubMed

Briles, Travis C; Yost, Dylan C; Cingöz, Arman; Ye, Jun; Schibli, Thomas R

2010-05-10

We present a high bandwidth piezoelectric-actuated mirror for length stabilization of an optical cavity. The actuator displays a transfer function with a flat amplitude response and greater than 135 masculine phase margin up to 200 kHz, allowing a 180 kHz unity gain frequency to be achieved in a closed servo loop. To the best of our knowledge, this actuator has achieved the largest servo bandwidth for a piezoelectric transducer (PZT). The actuator should be very useful in a wide variety of applications requiring precision control of optical lengths, including laser frequency stabilization, optical interferometers, and optical communications. (c) 2010 Optical Society of America.

A comparative study of linear and nonlinear MIMO feedback configurations

NASA Technical Reports Server (NTRS)

Desoer, C. A.; Lin, C. A.

1984-01-01

In this paper, a comparison is conducted of several feedback configurations which have appeared in the literature (e.g. unity-feedback, model-reference, etc.). The linear time-invariant multi-input multi-output case is considered. For each configuration, the stability conditions are specified, the relation between achievable I/O maps and the achievable disturbance-to-output maps is examined, and the effect of various subsystem perturbations on the system performance is studied. In terms of these considerations, it is demonstrated that one of the configurations considered is better than all the others. The results are then extended to the nonlinear multi-input multi-output case.

1. PERSPECTIVE VIEW OF KEX PLANT, FORMER CALLAWAY MILLS UNITY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. PERSPECTIVE VIEW OF KEX PLANT, FORMER CALLAWAY MILLS UNITY COTTON MILL (A. FRANCIS WALKER, 1900-01) FROM DUNSON STREET. UNITY COTTON MILL WAS THE FIRST OF SEVERAL TEXTILE MILLS BUILT BY THE CALLAWAY MILLS GROUP IN SOUTHWEST LAGRANGE DURING THE EARLY TWENTIETH CENTURY. NOTE REMAINING PORTION OF ORIGINAL WATER TANK TOWER IN MIDDLE OF PHOTOGRAPH. - Unity Cotton Mill, 815 Leeman Street, La Grange, Troup County, GA

Robust nonfullerene solar cells approaching unity external quantum efficiency enabled by suppression of geminate recombination.

PubMed

Baran, Derya; Gasparini, Nicola; Wadsworth, Andrew; Tan, Ching Hong; Wehbe, Nimer; Song, Xin; Hamid, Zeinab; Zhang, Weimin; Neophytou, Marios; Kirchartz, Thomas; Brabec, Christoph J; Durrant, James R; McCulloch, Iain

2018-05-25

Nonfullerene solar cells have increased their efficiencies up to 13%, yet quantum efficiencies are still limited to 80%. Here we report efficient nonfullerene solar cells with quantum efficiencies approaching unity. This is achieved with overlapping absorption bands of donor and acceptor that increases the photon absorption strength in the range from about 570 to 700 nm, thus, almost all incident photons are absorbed in the active layer. The charges generated are found to dissociate with negligible geminate recombination losses resulting in a short-circuit current density of 20 mA cm -2 along with open-circuit voltages >1 V, which is remarkable for a 1.6 eV bandgap system. Most importantly, the unique nano-morphology of the donor:acceptor blend results in a substantially improved stability under illumination. Understanding the efficient charge separation in nonfullerene acceptors can pave the way to robust and recombination-free organic solar cells.

The Unity connecting module rests inside the payload bay of Endeavour

NASA Technical Reports Server (NTRS)

1998-01-01

The Unity connecting module rests inside the payload bay of the orbiter Endeavour at Launch Pad 39A. The first U.S. element of the International Space Station (ISS), Unity is scheduled for launch Dec. 3, 1998, on Mission STS-88. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach it to the Russian-built Zarya control module which will be in orbit at that time. The mission is expected to last nearly 12 days, landing back at the Kennedy Space Center on Dec. 14.

A Cost to Benefit Analysis of a Next Generation Electric Power Distribution System

NASA Astrophysics Data System (ADS)

Raman, Apurva

This thesis provides a cost to benefit analysis of the proposed next generation of distribution systems- the Future Renewable Electric Energy Distribution Management (FREEDM) system. With the increasing penetration of renewable energy sources onto the grid, it becomes necessary to have an infrastructure that allows for easy integration of these resources coupled with features like enhanced reliability of the system and fast protection from faults. The Solid State Transformer (SST) and the Fault Isolation Device (FID) make for the core of the FREEDM system and have huge investment costs. Some key features of the FREEDM system include improved power flow control, compact design and unity power factor operation. Customers may observe a reduction in the electricity bill by a certain fraction for using renewable sources of generation. There is also a possibility of huge subsidies given to encourage use of renewable energy. This thesis is an attempt to quantify the benefits offered by the FREEDM system in monetary terms and to calculate the time in years required to gain a return on investments made. The elevated cost of FIDs needs to be justified by the advantages they offer. The result of different rates of interest and how they influence the payback period is also studied. The payback periods calculated are observed for viability. A comparison is made between the active power losses on a certain distribution feeder that makes use of distribution level magnetic transformers versus one that makes use of SSTs. The reduction in the annual active power losses in the case of the feeder using SSTs is translated onto annual savings in terms of cost when compared to the conventional case with magnetic transformers. Since the FREEDM system encourages operation at unity power factor, the need for installing capacitor banks for improving the power factor is eliminated and this reflects in savings in terms of cost. The FREEDM system offers enhanced reliability when compared to a conventional system. The payback periods observed support the concept of introducing the FREEDM system.

Unity connecting module before being moved to new site in SSPF

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility (SSPF), the Unity connecting module, part of the International Space Station, sits on a workstand before its move to a new location in the SSPF. As the primary payload on mission STS-88, scheduled to launch Dec. 3, 1998, Unity will be mated to the Russian-built Zarya control module which should already be in orbit at that time. In the SSPF, Unity is undergoing testing such as the Pad Demonstration Test to verify the compatibility of the module with the Space Shuttle, as well as the ability of the astronauts to send and receive commands to Unity from the flight deck of the orbiter, and the common berthing mechanism to which other space station elements will dock. Unity is expected to be ready for installation into the Shuttle's payload canister on Oct. 25, and transported to Launch Pad 39-A on Oct. 27.

Unity connecting module moving to new site in SSPF

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility (SSPF) Unity is suspended in air as it is moved to a now location in the SSPF. At right, visitors watch through a viewing window, part of the visitors tour at the Center. As the primary payload on mission STS-88, scheduled to launch Dec. 3, 1998, Unity will be mated to the Russian-built Zarya control module which should already be in orbit at that time. In the SSPF, Unity is undergoing testing such as the Pad Demonstration Test to verify the compatibility of the module with the Space Shuttle, as well as the ability of the astronauts to send and receive commands to Unity from the flight deck of the orbiter, and the common berthing mechanism to which other space station elements will dock. Unity is expected to be ready for installation into the payload canister on Oct. 25, and transported to Launch Pad 39-A on Oct. 27.

Unity connecting module moving to new site in SSPF

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility (SSPF), workers guide the suspended Unity connecting module, part of the International Space Station, as they move it to another location in the SSPF. As the primary payload on mission STS-88, scheduled to launch Dec. 3, 1998, Unity will be mated to the Russian-built Zarya control module which should already be in orbit at that time. In the SSPF, Unity is undergoing testing such as the Pad Demonstration Test to verify the compatibility of the module with the Space Shuttle, as well as the ability of the astronauts to send and receive commands to Unity from the flight deck of the orbiter, and the common berthing mechanism to which other space station elements will dock. Unity is expected to be ready for installation into the payload canister on Oct. 25, and transported to Launch Pad 39-A on Oct. 27.

Unity connecting module lifted from workstand before move to new site in SSPF

NASA Technical Reports Server (NTRS)

1998-01-01

Workers in the Space Station Processing Facility (SSPF) oversee the lifting of the Unity connecting module, part of the International Space Station, for its move to another location in the SSPF. As the primary payload on mission STS-88, scheduled to launch Dec. 3, 1998, Unity will be mated to the Russian-built Zarya control module which should already be in orbit at that time. In the SSPF, Unity is undergoing testing such as the Pad Demonstration Test to verify the compatibility of the module with the Space Shuttle, as well as the ability of the astronauts to send and receive commands to Unity from the flight deck of the orbiter, and the common berthing mechanism to which other space station elements will dock. Unity is expected to be ready for installation into the Shuttle's payload canister on Oct. 25, and transported to Launch Pad 39-A on Oct. 27.

Unity connecting module moving to new site in SSPF

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Station Processing Facility (SSPF) the Unity connecting module, part of the International Space Station, hangs suspended during its move to another location in the SSPF. As the primary payload on mission STS-88, scheduled to launch Dec. 3, 1998, Unity will be mated to the Russian-built Zarya control module which should already be in orbit at that time. In the SSPF, Unity is undergoing testing such as the Pad Demonstration Test to verify the compatibility of the module with the Space Shuttle, as well as the ability of the astronauts to send and receive commands to Unity from the flight deck of the orbiter, and the common berthing mechanism to which other space station elements will dock. Unity is expected to be ready for installation into the Shuttle's payload canister on Oct. 25, and transported to Launch Pad 39-A on Oct. 27.

Unity connecting module prepared for move to new site in SSPF

NASA Technical Reports Server (NTRS)

1998-01-01

Workers in the Space Station Processing Facility (SSPF) attach a frame to lift the Unity connecting module, part of the International Space Station, for its move to another location in the SSPF. As the primary payload on mission STS-88, scheduled to launch Dec. 3, 1998, Unity will be mated to the Russian-built Zarya control module which should already be in orbit at that time. In the SSPF, Unity is undergoing testing such as the Pad Demonstration Test to verify the compatibility of the module with the Space Shuttle, as well as the ability of the astronauts to send and receive commands to Unity from the flight deck of the orbiter, and the common berthing mechanism to which other space station elements will dock. Unity is expected to be ready for installation into the Shuttle's payload canister on Oct. 25, and transported to Launch Pad 39-A on Oct. 27.

The Unity connecting module rests inside the payload bay of Endeavour

NASA Technical Reports Server (NTRS)

1998-01-01

This fish-eye view of the Unity connecting module reveals its immense size relative to the workers (below right). Unity rests inside the open payload bay of the orbiter Endeavour on Launch Pad 39A. At the top of bay is the docking mechanism first used with launches to Mir, the Russian space station. Unity is the first U.S. element of the International Space Station (ISS) and is scheduled for launch Dec. 3, 1998, on Mission STS-88. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach it to the Russian-built Zarya control module which will be in orbit at that time. The mission is expected to last nearly 12 days, landing back at the Kennedy Space Center on Dec. 14.

Detector with internal gain for short-wave infrared ranging applications

NASA Astrophysics Data System (ADS)

Fathipour, Vala; Mohseni, Hooman

2017-09-01