18 CFR 284.270 - Reporting requirements.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Reporting requirements. 284.270 Section 284.270 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... the emergency; (4) The estimated total amount and average daily amount of emergency natural gas to be...

Emitted Power of Jupiter Based on Cassini CIRS and VIMS Observations

NASA Technical Reports Server (NTRS)

Li, Liming; Baines, Kevin H.; Smith, Mark A.; West, Robert A.; Perez-Hoyos, Santiago; Trammel, Harold J.; Simon-Miller, Amy A.; Conrath, Barney J.; Gierasch, Peter J.; Orton, Glenn S.;

Emitted Power Of Jupiter Based On Cassini CIRS And VIMS Observations

NASA Technical Reports Server (NTRS)

Li, Liming; Baines, Kevin H.; Smith, Mark A.; West, Robert A.; Perez-Hoyos, Santiago; Trammel, Harold J.; Simon-Miller, Amy A.; Conrath, Barney J.; Gierasch, Peter J.; Orton, Glenn S.;

Driver development of IFE power plant in Japan Collaborative process with industry and industrial applications

NASA Astrophysics Data System (ADS)

Nakai, S.; Yamanaka, M.; Kitagawa, Y.; Fujita, K.; Heya, M.; Mima, K.; Izawa, Y.; Nakatsuka, M.; Murakami, M.; Ueda, K.; Sasaki, T.; Mori, Y.; Kanabe, T.; Hiruma, T.; Kan, H.; Kawashima, T.

2006-06-01

The typical specifications of the laser driver for a commercial IFE power plant are (1) total energy (MJ/pulse) with a tailored 20-40 ns pulse, (2) repetition operation (˜ 10 Hz), (3) efficiency (˜ 10%) with enough robustness and low cost. The key elements of the DPSSL driver technology are under development with HALNA. The HALNA 10 (High Average-power Laser for Nuclear-fusion Application) demonstrated 10 J × 10 Hz operation and the HALNA 100 (100 J × 10 Hz) is now under construction. By using the high average power and high intensity lasers, new industrial applications are being proceeded. The collaborative process for the development of high power laser with industry and for the industrial applications is effective and essential in the development of the laser driver for IFE power plant.

Mode-locked Ti:sapphire laser oscillators pumped by wavelength-multiplexed laser diodes

NASA Astrophysics Data System (ADS)

Sugiyama, Naoto; Tanaka, Hiroki; Kannari, Fumihiko

2018-05-01

We directly pumped a Ti:sapphire laser by combining 478 and 520 nm laser diodes to prevent the effect of absorption loss induced by the pump laser of shorter wavelengths (∼450 nm). We obtain a continuous-wave output power of 660 mW at a total incident pump power of 3.15 W. We demonstrate mode locking using a semiconductor saturable absorber mirror, and 126 fs pulses were obtained at a repetition rate of 192 MHz. At the maximum pump power, the average output power is 315 mW. Shorter mode-locked pulses of 42 and 48 fs were respectively achieved by Kerr-lens mode locking with average output powers of 280 and 360 mW at a repetition rate of 117 MHz.

Estimating Engine Airflow in Gas-Turbine Powered Aircraft with Clean and Distorted Inlet Flows

NASA Technical Reports Server (NTRS)

Williams, J. G.; Steenken, W. G.; Yuhas, A. J.

1996-01-01

The P404-GF-400 Powered F/A-18A High Alpha Research Vehicle (HARV) was used to examine the impact of inlet-generated total-pressure distortion on estimating levels of engine airflow. Five airflow estimation methods were studied. The Reference Method was a fan corrected airflow to fan corrected speed calibration from an uninstalled engine test. In-flight airflow estimation methods utilized the average, or individual, inlet duct static- to total-pressure ratios, and the average fan-discharge static-pressure to average inlet total-pressure ratio. Correlations were established at low distortion conditions for each method relative to the Reference Method. A range of distorted inlet flow conditions were obtained from -10 deg. to +60 deg. angle of attack and -7 deg. to +11 deg. angle of sideslip. The individual inlet duct pressure ratio correlation resulted in a 2.3 percent airflow spread for all distorted flow levels with a bias error of -0.7 percent. The fan discharge pressure ratio correlation gave results with a 0.6 percent airflow spread with essentially no systematic error. Inlet-generated total-pressure distortion and turbulence had no significant impact on the P404-GE400 engine airflow pumping. Therefore, a speed-flow relationship may provide the best airflow estimate for a specific engine under all flight conditions.

Micro-hydrokinetic turbine potential for sustainable power generation in Malaysia

NASA Astrophysics Data System (ADS)

Salleh, M. B.; Kamaruddin, N. M.; Mohamed-Kassim, Z.

2018-05-01

Micro-hydrokinetic turbine (μ-HKT) technology is considered a viable option for sustainable, green and low cost power production. In recent years, there is growing number of research and development on this technology to replace conventional power production systems such as fossil fuel as well as to provide off-grid electrification to communities in remote areas. This paper provides an overview of μ-HKT system, the implementation of the technology and the potential of using μ-HKT in Malaysia. A review on the climate in Malaysia shows that its average annual rainfall is higher than the world’s average annual rainfall. It contributes to the total hydropower resource of about 29,000 MW which is available all year-round. Currently, hydropower resource contributes only 7.4% of the total electrical power production in Malaysia but is expected to increase with the main contribution coming from μ-HKT. However, the μ-HKT technology has not been adopted in Malaysia due to some challenges that hinder the development of the system. This paper reviews the μ-HKT technology and its potential for application in Malaysia, particularly in remote areas.

High resolution light microscopic evaluation of boar semen quality sperm cytoplasmic droplet retention in relationship with boar fertility parameters.

PubMed

Lovercamp, K W; Safranski, T J; Fischer, K A; Manandhar, G; Sutovsky, M; Herring, W; Sutovsky, P

2007-01-01

The purpose of this study was to investigate the relationship between fertility and quantitative measures of boar semen quality, including various patterns of sperm cytoplasmic droplet (CD) retention, as determined by high power differential interference contrast (DIC) microscopy. A total of 116 ejaculates were collected from a nucleus herd of 18 Large White boars over an eight month period. Semen quality parameters were analyzed for each ejaculate by calculating the percentage of normal spermatozoa, spermatozoa possessing a CD in the proximal, distal, or distal midpiece reflex position, total spermatozoa with an attached cytoplasmic droplet, spermatozoa with non-CD related aberrations and total spermatozoa with abnormalities. Of the 116 ejaculates received, 71 ejaculates from 13 boars had corresponding fertility data from single-sire inseminations of multiparous sows. The fertility data included farrowing rate (FR) and total number born (TNB). The monthly FR encompassed one month before and one month after the date of semen collection. Detection of differences for fertility and semen quality parameters was performed by separating the boars into either an above-average or below-average group based on the mean FR (74.01 +/- 1.43%) or TNB (12.34 +/- 0.17) for the study. For FR, the boars in the below-average group had a significantly lower percentage of normal spermatozoa and significantly higher percentage of spermatozoa possessing distal CDs, total attached CDs and total abnormalities compared to the boars in the above-average group. Conversely, for TNB there were no significant differences between the above- and below-average groups for the semen quality parameters. These data suggest that the attached CD may negatively affect FR, but not TNB. The detection of relationships between the boar fertility parameters and the retention of the sperm CD after ejaculation, document the advantage of high power DIC microscopy in conventional semen evaluation.

Output power distributions of terminals in a 3G mobile communication network.

PubMed

Persson, Tomas; Törnevik, Christer; Larsson, Lars-Eric; Lovén, Jan

2012-05-01

The objective of this study was to examine the distribution of the output power of mobile phones and other terminals connected to a 3G network in Sweden. It is well known that 3G terminals can operate with very low output power, particularly for voice calls. Measurements of terminal output power were conducted in the Swedish TeliaSonera 3G network in November 2008 by recording network statistics. In the analysis, discrimination was made between rural, suburban, urban, and dedicated indoor networks. In addition, information about terminal output power was possible to collect separately for voice and data traffic. Information from six different Radio Network Controllers (RNCs) was collected during at least 1 week. In total, more than 800000 h of voice calls were collected and in addition to that a substantial amount of data traffic. The average terminal output power for 3G voice calls was below 1 mW for any environment including rural, urban, and dedicated indoor networks. This is <1% of the maximum available output power. For data applications the average output power was about 6-8 dB higher than for voice calls. For rural areas the output power was about 2 dB higher, on average, than in urban areas. Copyright © 2011 Wiley Periodicals, Inc.

46 CFR 163.002-21 - Approval tests.

Code of Federal Regulations, 2010 CFR

2010-10-01

... raised and lowered under power operation until a total distance of at least 150 meters (500 feet) has... least 5 meters (16 feet). The average speed of raising the ladder or lift platform and the average lowering speed during this test must both be between 15 and 21 meters per minute (50 and 70 feet per minute...

A Low-Power Instruction Issue Queue for Microprocessors

NASA Astrophysics Data System (ADS)

Watanabe, Shingo; Chiyonobu, Akihiro; Sato, Toshinori

Instruction issue queue is a key component which extracts instruction level parallelism (ILP) in modern out-of-order microprocessors. In order to exploit ILP for improving processor performance, instruction queue size should be increased. However, it is difficult to increase the size, since instruction queue is implemented by a content addressable memory (CAM) whose power and delay are much large. This paper introduces a low power and scalable instruction queue that replaces the CAM with a RAM. In this queue, instructions are explicitly woken up. Evaluation results show that the proposed instruction queue decreases processor performance by only 1.9% on average. Furthermore, the total energy consumption is reduced by 54% on average.

Wastewater Management Study for Cleveland-Akron and Three Rivers Watershed Areas, 1970. Appendix III. Municipal Wastewater and Stormwater Runoff.

DTIC Science & Technology

1973-08-01

average to peak flows. Cost estimates include provision of diesel-electric standby power generation. Sewage pumping stations are generally designed for a...20 year design period. The pumping station power costs have been based on a pump efficiency of 75%, the appropriate pumping head, and a power cost of...considered by the project evaluators. Table E4 shows both the total power generating capacity of the station as well as that which is normally available

Estimates of water use and trends in the Colorado River Basin, Southwestern United States, 1985–2010

USGS Publications Warehouse

Maupin, Molly A.; Ivahnenko, Tamara I.; Bruce, Breton

2018-06-26

The Colorado River Basin (CRB) drains 246,000 square miles and includes parts of California, Colorado, Nevada, New Mexico, Utah, and Wyoming, and all of Arizona (Basin States). This report contains water-use estimates by category of use for drainage basins (Hydrologic Unit Code 8; HUC‑8) within the CRB from 1985 to 2010, at 5-year intervals. Estimates for public supply, domestic, commercial, industrial, irrigation, livestock, mining, aquaculture, hydroelectric and thermoelectric power, and wastewater returns are tabulated as (1) water withdrawals from groundwater or surface‑water sources of fresh or saline quality, (2) water delivered for domestic use, (3) wastewater returns and instream use (hydroelectric), and (4) consumptive use, or water that is consumed (USGS definition) and not available for immediate reuse. Water transported outside of the CRB (interbasin transfers) is not included as part of withdrawals and are not accounted for in any category of use within the CRB.Total withdrawals in the CRB (excluding interbasin transfers) averaged about 17 million acre-feet (maf) from 1985 to 2010, peaked at about 17.76 maf in 2000, and reached their lowest levels of 16.43 maf in 1990. Interbasin transfers to serve mostly public-supply and irrigation needs outside of the CRB are reported for 2000, 2005, and 2010 only, and averaged 5.40 maf. More surface water was used in the CRB than groundwater, averaging about 78 percent of total withdrawals, and its use increased less than 2 percent from 1985 to 2010, while groundwater withdrawals decreased about 12 percent. From 1985 to 2010, surface water averaged 98 percent of withdrawals in the upper CRB, and about 59 percent in the lower CRB. Nearly all withdrawals were freshwater, but some saline groundwater was used for mining and self-supplied industrial.Interbasin transfers have a large effect on flows in the Colorado River and are listed in this report separately with no explanation of how the water is used outside of the CRB. There are 34 interbasin transfers that conveyed an estimated 5.83, 5.20, and 5.18 maf out of the CRB in 2000, 2005, and 2010, respectively. The largest interbasin transfers are in the lower CRB and convey surface water (Colorado River water) to southern California; these accounted for 80 to 84 percent of total interbasin transfers in the CRB from 2000 to 2010. Intrabasin transfers are conveyances of surface water that cross drainage basin or State boundaries in the CRB, but the water does not leave the CRB. There are many intrabasin transfers in the CRB, but this report lists 11 that are mostly in the State of Colorado. The largest is the Central Arizona Project (CAP), through which more than 1.00 maf of water was provided to irrigate nearly 1 million acres in Maricopa, Pinal, and Pima Counties, as well as provide municipal water for Phoenix and Tucson, Arizona, during 2000, 2005, and 2010. In 2010, interbasin and intrabasin transfers accounted for 24 and 11 percent of the total water withdrawals in CRB, respectively, with the larger volumes being conveyed out of the lower CRB.Total population in the CRB increased from 4.56 to 9.44 million people from 1985 to 2010. Most of those people were in the lower CRB, with 86 percent of the total in 1985, and 90 percent of the total in 2010. Total public-supply withdrawals in the CRB provided most people with their potable water, and averaged about 1.63 maf from 1985 to 2010, ranging from about 1.07 maf in 1985 to about 2.10 maf in 2010, when it peaked. Most of public-supply withdrawals occurred in the lower CRB, ranging from 87 to 91 percent of total public-supply withdrawals in the CRB over the 25 years. Total domestic use, comprised of public-supply deliveries and self-supply domestic withdrawals, increased more than 90 percent from 1985 to 2010, from about 0.80 maf to about 1.54 maf. Domestic daily per-capita use rates in the CRB ranged from about 144 (1985) to about 121 (2000) gallons (gal) per‑capita between 1985 and 2010. When comparing domestic daily per-capita rates for the upper and lower CRB, people in the lower CRB, on average, used less water for domestic purposes at 128 gal per-capita daily (1985–2010), while those in the upper CRB for the same time period averaged 133 gal per-capita daily. The trend in daily per-capita use rates for the entire CRB fluctuated between the reporting years, but decreased overall, indicating that more people used less water in 2010 than in 1985, likely due to improved infrastructure, conservation, and improvements to water using appliances in homes and businesses.Irrigation accounted for most total withdrawals in the CRB, excluding instream use for hydroelectric power and interbasin transfers, averaging 85 percent from 1985 to 2010. Far more surface water than groundwater was used for irrigation in both the upper and lower CRB, but in the upper CRB, it accounted for an average of more than 98 percent of the total withdrawals (1985–2010), whereas in the lower CRB, surface-water withdrawals for irrigation averaged 61 percent of total withdrawals. On average, the upper CRB accounted for 56 percent of total irrigated acres, and the irrigation systems in the upper CRB trended towards more efficient sprinkler systems from 1985 to 2010. Long-term drought in the CRB substantially decreased the amount of streamflow available for irrigation. Increases in micro-irrigation acres, which can have efficiencies that exceed 90 percent and require 20–50 percent less water than sprinkler systems, likely contributed to reduced withdrawals in the lower CRB.For thermoelectric power, total withdrawals, including the use of reclaimed wastewater, were greater in the upper CRB from 1985 through 2005. In 2010, the lower CRB exceeded the upper by only 11,000 acre-feet. On average, thermoelectric consumptive use accounted for about 80 percent of the total withdrawals; however, consumptive-use data in the upper CRB was incomplete. Surface water was the primary source in the upper CRB and groundwater was the primary source in the lower CRB. In the CRB overall, water withdrawals for thermoelectric generation has decreased since 2000, except for groundwater withdrawals in the lower CRB. Power generation at thermoelectric plants was greater in the upper CRB from 1985 to 2000, and after 2005 the difference in power generation was small; however, the upper CRB continued to have more power generation. In both the upper and lower CRB, power generation increased from 1985 to 2005.

All particle energy spectrum of cosmic rays in 10 to the 15th power - 10 to the 20th power eV region

NASA Technical Reports Server (NTRS)

Krasilnikov, D. D.; Dyakonov, M. N.; Ivanov, A. A.; Kolosov, V. A.; Lischenyuk, F. F.; Sleptsov, I. Y.

1985-01-01

Average estimations of the shower energy components are presented and their sum gives E sub 0 (Rho sub 600) - an average function of the relation of E sub 0 with the shower size parameter Rho sub 600 measured at the Yakutsk extensive air showers (EAS) array. Using this relation to the EAS spectrum obtained at the Akeno and Yakutsk arrays the energy spectrum of the cosmic ray total flux within 15 lg (E sub 0,eV) 20 by the EAS methods is recovered.

Nuclear-powered ships

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

Not Available

1992-07-01

This paper reports that using Puget Sound Naval Shipyard as a model, GAO examined the Navy's accounting practices at nuclear shipyards. In fiscal year 1991, Puget Sound worked on 24 nuclear-powered and three conventionally powered ships. About 31 percent of the workdays and 35 percent of total costs were for nuclear work. The average cost per workday for nuclear labor was 25 percent higher than for non-nuclear work, and the average cost per day for overhead for nuclear work was about 60 percent higher. These higher costs are due to the complexity of nuclear work, which requires a higher levelmore » of services, and the higher cost of specially trained workers and specialized shipyard departments that support nuclear work.« less

75 FR 11104 - Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-10

... energy produced (wind, solar, and manure/methane digester), installation cost, year installed, if any energy was sold onto a power grid, and the average payment received per kilowatt hour or total amount of...

Performance of an off-grid solar home in northwestern Vermont

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

Rawlings, L.K.

1997-12-31

In 1995 an off-grid integrated solar home was built in Middlesex, VT for Peter Clark and Gloria DeSousa. This home was included as a pilot home in the US DOE PV:BONUS program to develop factory-built integrated solar homes. The home incorporates a 1.44 KW PV system, 0.6 KW of wind turbine capacity, and very high-efficiency electrical loads. The home also features passive solar design, high-efficiency heating systems, and a greenhouse-based septic treatment system. The performance of the PV system and the wind system, and the total power usage of the household, are measured and recorded by a data acquisition system.more » The home`s electrical loads have operated very efficiently, using on average about one tenth the power used by the average American residence. The PV system has operated reliably and efficiently, providing about 97% of the power needs of the home. The wind turbines have operated efficiently, but the wind regime at the site has not been sufficient to generate more than 1% of the total power needs. The other 2% has been provided by a gasoline backup generator.« less

Friction in Total Hip Joint Prosthesis Measured In Vivo during Walking

PubMed Central

Damm, Philipp; Dymke, Joern; Ackermann, Robert; Bender, Alwina; Graichen, Friedmar; Halder, Andreas; Beier, Alexander; Bergmann, Georg

2013-01-01

Friction-induced moments and subsequent cup loosening can be the reason for total hip joint replacement failure. The aim of this study was to measure the in vivo contact forces and friction moments during walking. Instrumented hip implants with Al2O3 ceramic head and an XPE inlay were used. In vivo measurements were taken 3 months post operatively in 8 subjects. The coefficient of friction was calculated in 3D throughout the whole gait cycle, and average values of the friction-induced power dissipation in the joint were determined. On average, peak contact forces of 248% of the bodyweight and peak friction moments of 0.26% bodyweight times meter were determined. However, contact forces and friction moments varied greatly between individuals. The friction moment increased during the extension phase of the joint. The average coefficient of friction also increased during this period, from 0.04 (0.03 to 0.06) at contralateral toe off to 0.06 (0.04 to 0.08) at contralateral heel strike. During the flexion phase, the coefficient of friction increased further to 0.14 (0.09 to 0.23) at toe off. The average friction-induced power throughout the whole gait cycle was 2.3 W (1.4 W to 3.8 W). Although more parameters than only the synovia determine the friction, the wide ranges of friction coefficients and power dissipation indicate that the lubricating properties of synovia are individually very different. However, such differences may also exist in natural joints and may influence the progression of arthrosis. Furthermore, subjects with very high power dissipation may be at risk of thermally induced implant loosening. The large increase of the friction coefficient during each step could be caused by the synovia being squeezed out under load. PMID:24260114

Friction in total hip joint prosthesis measured in vivo during walking.

PubMed

Damm, Philipp; Dymke, Joern; Ackermann, Robert; Bender, Alwina; Graichen, Friedmar; Halder, Andreas; Beier, Alexander; Bergmann, Georg

2013-01-01

Friction-induced moments and subsequent cup loosening can be the reason for total hip joint replacement failure. The aim of this study was to measure the in vivo contact forces and friction moments during walking. Instrumented hip implants with Al2O3 ceramic head and an XPE inlay were used. In vivo measurements were taken 3 months post operatively in 8 subjects. The coefficient of friction was calculated in 3D throughout the whole gait cycle, and average values of the friction-induced power dissipation in the joint were determined. On average, peak contact forces of 248% of the bodyweight and peak friction moments of 0.26% bodyweight times meter were determined. However, contact forces and friction moments varied greatly between individuals. The friction moment increased during the extension phase of the joint. The average coefficient of friction also increased during this period, from 0.04 (0.03 to 0.06) at contralateral toe off to 0.06 (0.04 to 0.08) at contralateral heel strike. During the flexion phase, the coefficient of friction increased further to 0.14 (0.09 to 0.23) at toe off. The average friction-induced power throughout the whole gait cycle was 2.3 W (1.4 W to 3.8 W). Although more parameters than only the synovia determine the friction, the wide ranges of friction coefficients and power dissipation indicate that the lubricating properties of synovia are individually very different. However, such differences may also exist in natural joints and may influence the progression of arthrosis. Furthermore, subjects with very high power dissipation may be at risk of thermally induced implant loosening. The large increase of the friction coefficient during each step could be caused by the synovia being squeezed out under load.

Mercury emission and speciation of coal-fired power plants in China

NASA Astrophysics Data System (ADS)

Wang, S. X.; Zhang, L.; Li, G. H.; Wu, Y.; Hao, J. M.; Pirrone, N.; Sprovieri, F.; Ancora, M. P.

2010-02-01

Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of Selective Catalytic Reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92-27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66-94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.

Mercury emission and speciation of coal-fired power plants in China

NASA Astrophysics Data System (ADS)

Wang, S.; Zhang, L.; Li, G.; Wu, Y.; Hao, J.; Pirrone, N.; Sprovieri, F.; Ancora, M. P.

2009-11-01

Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of selective catalyst reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92-27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66-94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.

Intermediate photovoltaic system application experiment operational performance report: Volume 5, for Beverly High School, Beverly, Mass.

NASA Astrophysics Data System (ADS)

1982-02-01

Performance data for the month of January, 1982 for a grid connected photovoltaic power supply in Massachusetts are presented. Data include: monthly and daily electrical energy produced; monthly and daily solar energy incident on the array; monthly and daily array efficiency; plots of energy produced as a function of power level, voltage, cell temperature and time of day; power conditioner input, output and efficiency for each of two individual units and for the total power conditioning system; photovoltaic system efficiency; capacity factor; PV system to load and grid to load energies and corresponding dollar values; daily energy supplies to the load by the PV system; daily PV system availability; monthly and hourly insolation; monthly and hourly temperature average; monthly and hourly wind speed; wind direction distribution; average heating and cooling degree days; number of freeze/thaw cycles; and the data acquisition mode and recording interval plot.

OPERATIONAL CHARACTERISTICS OF THE ARMOUR FISSION GAS GAMMA FACILITY

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

Terrell, C.W.; McElroy, W.N.

1958-10-31

As the reactor power level is changed frequently, the radiation levels in the gamma facility fluctuate. Data are presented to show the power dependency of the gamma dose rate and the manner of growth and decay. Additional data show the dependercy of the equilibrium gamma activity on the foel temperature and total system pressure. The final phase of the work is directed toward determining an average gamma energy by attenuation measurements with various thicknesses of several materials. The neutrou flux associated with the gas phase activity is determined by foil measurement. From the measurements of dose rate and average gammamore » energy, calculations to determine the number of curies of gas phase decay gamma activity per watt of reactor power are presented. (auth)« less

Power Recycled Weak Value Based Metrology

DTIC Science & Technology

2015-04-29

PAGE The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing...cavity, one is able to more efficiently use the input laser power by increasing the total power inside the interferometer. In the context of these weak...EV I EW LE T T ER S week ending 1 MAY 2015 0031-9007=15=114(17)=170801(5) 170801-1 © 2015 American Physical Society We consider a continuous wave laser

Low-complexity peak-to-average power ratio reduction scheme for flip-orthogonal frequency division multiplexing visible light communication system based on μ-law mapping

NASA Astrophysics Data System (ADS)

Wang, Jianping; Zhang, Peiran; Lu, Huimin; Feng, LiFang

2017-06-01

An orthogonal frequency division multiplexing (OFDM) technique called flipped OFDM (flip-OFDM) is apposite for a visible light communication system that needs the transmitted signal to be real and positive. Flip-OFDM uses two consecutive OFDM subframes to transmit the positive and negative parts of the signal. However, peak-to-average power ratio (PAPR) for flip-OFDM is increased tremendously due to the low value of total average power that arises from many zero values in both the positive and flipped frames. We first analyze the performance of flip-OFDM and perform a comparison with the conventional DC-biased OFDM (DCO-OFDM); then we propose a flip-OFDM scheme combined with μ-law mapping to reduce the high PAPR. The simulation results show that the PAPR of the system is reduced about 17.2 and 5.9 dB when compared with the normal flip-OFDM and DCO-OFDM signals, respectively.

Retrospective exposure assessment to airborne asbestos among power industry workers

PubMed Central

2010-01-01

Background A method of individually assessing former exposure to asbestos fibres is a precondition of risk-differentiated health surveillance. The main aims of our study were to assess former levels of airborne asbestos exposure in the power industry in Germany and to propose a basic strategy for health surveillance and the early detection of asbestos related diseases. Methods Between March 2002 and the end of 2006, we conducted a retrospective questionnaire based survey of occupational tasks and exposures with airborne asbestos fibres in a cohort of 8632 formerly asbestos exposed power industry workers. The data on exposure and occupation were entered into a specially designed computer programme, based on ambient monitoring of airborne asbestos fibre concentrations. The cumulative asbestos exposure was expressed as the product of the eight-hour time weighted average and the total duration of exposure in fibre years (fibres/cubic centimetre-years). Results Data of 7775 (90% of the total) participants working in installations for power generation, power distribution or gas supply could be evaluated. The power generation group (n = 5284) had a mean age of 56 years, were exposed for 20 years and had an average cumulative asbestos exposure of 42 fibre years. The occupational group of "metalworkers" (n = 1600) had the highest mean value of 79 fibre years. The corresponding results for the power distribution group (n = 2491) were a mean age of 45 years, a mean exposure duration of 12 years and an average cumulative asbestos exposure of only 2.5 fibre years. The gas supply workers (n = 512) had a mean age of 54 years and a mean duration of exposure of 15 years. Conclusions While the surveyed cohort as a whole was heavily exposed to asbestos dust, the power distribution group had a mean cumulative exposure of only 6% of that found in the power generation group. Based on the presented data, risk-differentiated disease surveillance focusing on metalworkers and electricians from the power generating industry seems justified. That combined with a sensitive examination technique would allow detecting asbestos related diseases early and efficiently. PMID:20579364

Emissions factors for gaseous and particulate pollutants from offshore diesel engine vessels in China

NASA Astrophysics Data System (ADS)

Zhang, F.; Chen, Y.; Tian, C.; Li, J.; Zhang, G.; Matthias, V.

2015-09-01

Shipping emissions have significant influence on atmospheric environment as well as human health, especially in coastal areas and the harbor districts. However, the contribution of shipping emissions on the environment in China still need to be clarified especially based on measurement data, with the large number ownership of vessels and the rapid developments of ports, international trade and shipbuilding industry. Pollutants in the gaseous phase (carbon monoxide, sulfur dioxide, nitrogen oxides, total volatile organic compounds) and particle phase (particulate matter, organic carbon, elemental carbon, sulfates, nitrate, ammonia, metals) in the exhaust from three different diesel engine power offshore vessels in China were measured in this study. Concentrations, fuel-based and power-based emissions factors for various operating modes as well as the impact of engine speed on emissions were determined. Observed concentrations and emissions factors for carbon monoxide, nitrogen oxides, total volatile organic compounds, and particulate matter were higher for the low engine power vessel than for the two higher engine power vessels. Fuel-based average emissions factors for all pollutants except sulfur dioxide in the low engine power engineering vessel were significantly higher than that of the previous studies, while for the two higher engine power vessels, the fuel-based average emissions factors for all pollutants were comparable to the results of the previous studies. The fuel-based average emissions factor for nitrogen oxides for the small engine power vessel was more than twice the International Maritime Organization standard, while those for the other two vessels were below the standard. Emissions factors for all three vessels were significantly different during different operating modes. Organic carbon and elemental carbon were the main components of particulate matter, while water-soluble ions and elements were present in trace amounts. Best-fit engine speeds during actual operation should be based on both emissions factors and economic costs.

Effect of heavy rain to the total received power

NASA Technical Reports Server (NTRS)

Iguchi, Toshio

1994-01-01

If the average power at the receiver is substantially reduced by heavy rain, the AGC (automatic gain control) circuit of the rain gauge will try to compensate this reduction by increasing the gain. If this happens, then the pulses created by rain drops are amplified more than they should be and the rainfall rate may be overestimated. If the effective diameter (blocking efficiency) of a particle is 2 mm and if the beam width is 2 cm, each particle will reduce the received power by 10 percent when it crosses the beam. Since the beam is blocked by water drops 75 percent of the total time according to the above calculation, the total received power may be reduced by 7.5 percent. To compensate this reduction to the reference value, the gain of amplifier will be increased by 8.1 percent. This increase of gain will increase all pulse sizes by the same fraction and result in the overestimate of the rainfall rate.

Green-diode-pumped femtosecond Ti:Sapphire laser with up to 450 mW average power.

PubMed

Gürel, K; Wittwer, V J; Hoffmann, M; Saraceno, C J; Hakobyan, S; Resan, B; Rohrbacher, A; Weingarten, K; Schilt, S; Südmeyer, T

2015-11-16

We investigate power-scaling of green-diode-pumped Ti:Sapphire lasers in continuous-wave (CW) and mode-locked operation. In a first configuration with a total pump power of up to 2 W incident onto the crystal, we achieved a CW power of up to 440 mW and self-starting mode-locking with up to 200 mW average power in 68-fs pulses using semiconductor saturable absorber mirror (SESAM) as saturable absorber. In a second configuration with up to 3 W of pump power incident onto the crystal, we achieved up to 650 mW in CW operation and up to 450 mW in 58-fs pulses using Kerr-lens mode-locking (KLM). The shortest pulse duration was 39 fs, which was achieved at 350 mW average power using KLM. The mode-locked laser generates a pulse train at repetition rates around 400 MHz. No complex cooling system is required: neither the SESAM nor the Ti:Sapphire crystal is actively cooled, only air cooling is applied to the pump diodes using a small fan. Because of mass production for laser displays, we expect that prices for green laser diodes will become very favorable in the near future, opening the door for low-cost Ti:Sapphire lasers. This will be highly attractive for potential mass applications such as biomedical imaging and sensing.

To flap or not to flap: a discussion between a fish and a jellyfish

NASA Astrophysics Data System (ADS)

Martin, Nathan; Roh, Chris; Idrees, Suhail; Gharib, Morteza

2016-11-01

Fish and jellyfish are known to swim by flapping and by periodically contracting respectively, but which is the more effective propulsion mechanism? In an attempt to answer this question, an experimental comparison is made between simplified versions of these motions to determine which generates the greatest thrust for the least power. The flapping motion is approximated by pitching plates while periodic contractions are approximated by clapping plates. A machine is constructed to operate in either a flapping or a clapping mode between Reynolds numbers 1,880 and 11,260 based on the average plate tip velocity and span. The effect of the total sweep angle, total sweep time, plate flexibility, and duty cycle are investigated. The average thrust generated and power required per cycle are compared between the two modes when their total sweep angle and total sweep time are identical. In general, operating in the clapping mode required significantly more power to generate a similar thrust compared to the flapping mode. However, modifying the duty cycle for clapping caused the effectiveness to approach that of flapping with an unmodified duty cycle. These results suggest that flapping is the more effective propulsion mechanism within the range of Reynolds numbers tested. This work was supported by the Charyk Bio-inspired Laboratory at the California Institute of Technology, the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469, and the Summer Undergraduate Research Fellowships program.

JPRS Report, Science & Technology Europe

DTIC Science & Technology

1988-09-08

with good temperature dependence. In the use of the 1B2B balance code, the average value of the optical power emitted by the photodiode equals one...Workers Clerical staff Total 9.7 6.6 18.8 10.3 28.8 8.4 9.4 General facilities 8.0 Table 2. MANPOWER ( Average staff in 1986) 170 180...Propulsion and High Temperatures Scientific Assistant Technical Assistant Special Assistant, Gas Turbines Modeling and Numerical Simulation in

The radio power reflected from rough and undulating ionospheric surfaces

NASA Astrophysics Data System (ADS)

Whitehead, J. D.; From, W. R.; Smith, L. G.

1984-08-01

It is shown for both rough and undulating surfaces that the mean radio power reflected by the ionosphere averaged over a sufficiently long time is exactly the same as for a smooth flat surface at the same height provided the sounder is equally sensitive for echoes from all directions. When making radio wave absorption measurements under spread conditions the total integrated power over the whole time the direct echoes are being received must be used but the distance attenuation factor must be calculated from the time of arrival of the first echo.

Hydrodynamic Trails Produced by Daphnia: Size and Energetics

PubMed Central

Wickramarathna, Lalith N.; Noss, Christian; Lorke, Andreas

2014-01-01

This study focuses on quantifying hydrodynamic trails produced by freely swimming zooplankton. We combined volumetric tracking of swimming trajectories with planar observations of the flow field induced by Daphnia of different size and swimming in different patterns. Spatial extension of the planar flow field along the trajectories was used to interrogate the dimensions (length and volume) and energetics (dissipation rate of kinetic energy and total dissipated power) of the trails. Our findings demonstrate that neither swimming pattern nor size of the organisms affect the trail width or the dissipation rate. However, we found that the trail volume increases with increasing organism size and swimming velocity, more precisely the trail volume is proportional to the third power of Reynolds number. This increase furthermore results in significantly enhanced total dissipated power at higher Reynolds number. The biggest trail volume observed corresponds to about 500 times the body volume of the largest daphnids. Trail-averaged viscous dissipation rate of the swimming daphnids vary in the range of to and the observed magnitudes of total dissipated power between and , respectively. Among other zooplankton species, daphnids display the highest total dissipated power in their trails. These findings are discussed in the context of fluid mixing and transport by organisms swimming at intermediate Reynolds numbers. PMID:24671019

Worldwide electricity used in data centers

NASA Astrophysics Data System (ADS)

Koomey, Jonathan G.

2008-07-01

The direct electricity used by data centers has become an important issue in recent years as demands for new Internet services (such as search, music downloads, video-on-demand, social networking, and telephony) have become more widespread. This study estimates historical electricity used by data centers worldwide and regionally on the basis of more detailed data than were available for previous assessments, including electricity used by servers, data center communications, and storage equipment. Aggregate electricity use for data centers doubled worldwide from 2000 to 2005. Three quarters of this growth was the result of growth in the number of the least expensive (volume) servers. Data center communications and storage equipment each contributed about 10% of the growth. Total electricity use grew at an average annual rate of 16.7% per year, with the Asia Pacific region (without Japan) being the only major world region with growth significantly exceeding that average. Direct electricity used by information technology equipment in data centers represented about 0.5% of total world electricity consumption in 2005. When electricity for cooling and power distribution is included, that figure is about 1%. Worldwide data center power demand in 2005 was equivalent (in capacity terms) to about seventeen 1000 MW power plants.

Durability Testing of Additively Manufactured High Power Microwave Structures

DTIC Science & Technology

2017-10-29

the aluminum anode, generating microwave powers in excess of 150 MW. After 100 shots on each structure, neither anode showed any signs of...with an average instantaneous peak total efficiency of 27% ± 10%. After 100 shots on each structure, neither anode showed any signs of...uniform axial magnetic field, which was varied on a per- shot basis from 0.13 to 0.31 T. A #304 stainless steel vacuum chamber housed the magnetron

AIRBORNE MICROORGANISMS IN BROILER PROCESSING PLANTS.

PubMed

KOTULA, A W; KINNER, J A

1964-05-01

Concentrations of total aerobic bacteria, molds, yeasts, coliforms, enterococci, and psychrophiles were determined in the air of two poultry processing plants with Andersen samplers and a mobile power supply. Total aerobic bacterial counts were highest in the dressing room, with diminishing numbers in the shackling, eviscerating, and holding rooms, when sampling was carried out during plant operation. The average counts per ft(3) of air in these four rooms were 2,200; 560; 230; and 62, respectively. (Each value is the average of 36 observations.) The number of organisms increased in the shackling and dressing rooms once processing was begun. Average total aerobic bacterial counts increased from 70 to 870 to 3,000 in the shackling room and from 310 to 4,900 to 7,000 in the dressing room when sampling was carried out at 5:00 am (before plant operations), 9:00 am, and 2:00 pm, respectively. (Each value is the mean of 12 observations.) Airborne molds might originate from a source other than the poultry being processed.

Airborne Microorganisms in Broiler Processing Plants

PubMed Central

Kotula, Anthony W.; Kinner, Jack A.

1964-01-01

Concentrations of total aerobic bacteria, molds, yeasts, coliforms, enterococci, and psychrophiles were determined in the air of two poultry processing plants with Andersen samplers and a mobile power supply. Total aerobic bacterial counts were highest in the dressing room, with diminishing numbers in the shackling, eviscerating, and holding rooms, when sampling was carried out during plant operation. The average counts per ft3 of air in these four rooms were 2,200; 560; 230; and 62, respectively. (Each value is the average of 36 observations.) The number of organisms increased in the shackling and dressing rooms once processing was begun. Average total aerobic bacterial counts increased from 70 to 870 to 3,000 in the shackling room and from 310 to 4,900 to 7,000 in the dressing room when sampling was carried out at 5:00 am (before plant operations), 9:00 am, and 2:00 pm, respectively. (Each value is the mean of 12 observations.) Airborne molds might originate from a source other than the poultry being processed. Images FIG. 3 PMID:14170951

Relationship between body composition, leg strength, anaerobic power, and on-ice skating performance in division I men's hockey athletes.

PubMed

Potteiger, Jeffrey A; Smith, Dean L; Maier, Mark L; Foster, Timothy S

2010-07-01

The purpose of this study was to examine relationships between laboratory tests and on-ice skating performance in division I men's hockey athletes. Twenty-one men (age 20.7 +/- 1.6 years) were assessed for body composition, isokinetic force production in the quadriceps and hamstring muscles, and anaerobic muscle power via the Wingate 30-second cycle ergometer test. Air displacement plethysmography was used to determine % body fat (%FAT), fat-free mass (FFM), and fat mass. Peak torque and total work during 10 maximal effort repetitions at 120 degrees .s were measured during concentric muscle actions using an isokinetic dynamometer. Muscle power was measured using a Monark cycle ergometer with resistance set at 7.5% of body mass. On-ice skating performance was measured during 6 timed 89-m sprints with subjects wearing full hockey equipment. First length skate (FLS) was 54 m, and total length skate (TLS) was 89 m with fastest and average skating times used in the analysis. Correlation coefficients were used to determine relationships between laboratory testing and on-ice performance. Subjects had a body mass of 88.8 +/- 7.8 kg and %FAT of 11.9 +/- 4.6. First length skate-Average and TLS-Average skating times were moderately correlated to %FAT ([r = 0.53; p = 0.013] and [r = 0.57; p = 0.007]) such that a greater %FAT was related to slower skating speeds. First length skate-Fastest was correlated to Wingate percent fatigue index (r = -0.48; p = 0.027) and FLS-Average was correlated to Wingate peak power per kilogram body mass (r = -0.43; p = 0.05). Laboratory testing of select variables can predict skating performance in ice hockey athletes. This information can be used to develop targeted and effective strength and conditioning programs that will improve on-ice skating speed.

An Improved Harmonic Current Detection Method Based on Parallel Active Power Filter

NASA Astrophysics Data System (ADS)

Zeng, Zhiwu; Xie, Yunxiang; Wang, Yingpin; Guan, Yuanpeng; Li, Lanfang; Zhang, Xiaoyu

2017-05-01

Harmonic detection technology plays an important role in the applications of active power filter. The accuracy and real-time performance of harmonic detection are the precondition to ensure the compensation performance of Active Power Filter (APF). This paper proposed an improved instantaneous reactive power harmonic current detection algorithm. The algorithm uses an improved ip -iq algorithm which is combined with the moving average value filter. The proposed ip -iq algorithm can remove the αβ and dq coordinate transformation, decreasing the cost of calculation, simplifying the extraction process of fundamental components of load currents, and improving the detection speed. The traditional low-pass filter is replaced by the moving average filter, detecting the harmonic currents more precisely and quickly. Compared with the traditional algorithm, the THD (Total Harmonic Distortion) of the grid currents is reduced from 4.41% to 3.89% for the simulations and from 8.50% to 4.37% for the experiments after the improvement. The results show the proposed algorithm is more accurate and efficient.

An Approach to Sensorless Detection of Human Input Torque and Its Application to Power Assist Motion in Electric Wheelchair

NASA Astrophysics Data System (ADS)

Kaida, Yukiko; Murakami, Toshiyuki

A wheelchair is an important apparatus of mobility for people with disability. Power-assist motion in an electric wheelchair is to expand the operator's field of activities. This paper describes force sensorless detection of human input torque. Reaction torque estimation observer calculates the total disturbance torque first. Then, the human input torque is extracted from the estimated disturbance. In power-assist motion, assist torque is synthesized according to the product of assist gain and the average torque of the right and left input torque. Finally, the proposed method is verified through the experiments of power-assist motion.

Seasonal thermoregulatory responses in mammals.

PubMed

Lovegrove, Barry G

2005-05-01

This study examined the proportional seasonal winter adjustments of total and mass-specific basal power (watts and watts g-1, respectively), thermal conductance (watts g-1 degrees C-1), non-shivering thermogenesis capacity (ratio of NST/basal power), body temperature ( degrees C), and body mass (g) of mammals. The responses are best summarized for three different body size classes; small mammals (<100 g), intermediate-sized mammals (0.1-10 kg), and large mammals (>10 kg). The principal adjustments of the small mammals center on energy conservation, especially the Dehnel Effect, the winter reduction in body size of as much as 50%, accompanied by reductions in mass-specific basal power. On average, these reductions reduce the total basal power approximately in direct proportion to the mass reductions. Reductions in mass-specific basal power are matched by concomitant reductions in conductance to maintain the setpoint body temperature during winter. The overall thermoregulatory adjustments in small mammals serve to (a) lower overall winter power consumption, (b) maintain the setpoint body temperature, and (c) lower the lower critical limit of thermoneutrality and hence thermoregulatory costs. In intermediate-size mammals, the seasonal response is centered more on increasing thermogenic capacity by increasing basal power and NST capacity, accompanied by predictable and large reductions in conductance. The Dehnel effect is negligible. Very large mammals undergo the largest reductions in total and mass-specific basal power and conductance. However, there are too few data to resolve whether the reductions in total basal power can be attributed to the Dehnel effect, because the moderate decreases in body mass may also be caused by nutritional stress. Apart from the seasonal changes in basal power, these observations are consistent with the predictions of Heldmaier's seasonal acclimatization model.

Abnormal cardiovascular responses induced by localized high power microwave exposure

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

Lu, S.-T; Brown, D.O.; Johnson, C.E.

1992-05-01

A hypothesis of microwave-induced circulatory under perfusion was tested in ketamine anesthetized rats whose heart rate, mean arterial pressure, pulse pressure, respiration rate, and body temperatures were monitored continuously. Fifty-eight ventral head and neck exposures in a waveguide consisted of sham-exposure and exposure to continuous wave (CW) and pulsed 1.25 GHz microwaves for 5 min. The 0.5 Hz and 16 Hz pulsemodulated microwaves were delivered at 400 kW peak power. The CW microwaves were 2 and 6.4 W. The average specific absorption rate was 4.75 W/kg per watt transmitted in the brain and 17.15 W/kg per watt transmitted in themore » neck. Respiration rate and mean arterial pressure were not altered. Changes in heart rate and pulse pressure were observed in rats exposed to higher power but not to the lower average power microwaves. Depression of pulse pressure, an indication of a decrease in stroke volume, and increased or decreased heart rate were noted in presence of whole-body hyperthermia. The cardiac output of those animals exposed to higher average power microwaves was considered to be below normal as hypothesized. Decreased cardiac output and normal mean arterial pressure resulted in an increase in the total peripheral resistance which was contrary to the anticipated thermal response of animals.« less

Physiological Interpretation of the Slope during an Isokinetic Fatigue Test.

PubMed

Bosquet, L; Gouadec, K; Berryman, N; Duclos, C; Gremeaux, V; Croisier, J-L

2015-07-01

To assess the relationship between selected measures (the slope and average performance) obtained during a high intensity isokinetic fatigue test of the knee (FAT) and relevant measures of anaerobic and aerobic capacities. 20 well-trained cyclists performed 3 randomly ordered sessions involving a FAT consisting in 30 reciprocal maximal concentric contractions of knee flexors and extensors at 180°.s(-1), a maximal continuous graded exercise test (GXT), and a Wingate anaerobic test (WAnT). The slope calculated from peak torque (PT) and total work (TW) of knee extensors was highly associated to maximal PT (r=-0.86) and maximal TW (r=-0.87) measured during FAT, and moderately associated to peak power output measured during the WAnT (r=-0.64 to -0.71). Average PT and average TW were highly associated to maximal PT (r=0.93) and maximal TW (r=0.96), to mean power output measured during WAnT (r=0.83-0.90) and moderately associated to maximal oxygen uptake (0.58-0.67). In conclusion, the slope is mainly determined by maximal anaerobic power, while average performance is a composite measure depending on both aerobic and anaerobic energy systems according to proportions that are determined by the duration of the test. © Georg Thieme Verlag KG Stuttgart · New York.

Ground-water use, locations of production wells, and areas irrigated using ground water in 1998, middle Humboldt River basin, north-central Nevada

USGS Publications Warehouse

Plume, Russell W.

2003-01-01

In 1998, ground water was being pumped from about 420 production wells in the middle Humboldt River Basin for a variety of uses. Principal uses were for agriculture, industry, mining, municipal, and power plant purposes. This report presents a compilation of the number and types of production wells, areas irrigated by ground water, and ground-water use in 14 hydrographic areas of the middle Humboldt River Basin in 1998. Annual pumping records for production wells usually are reported to the Nevada Division of Water Resources. However, operators of irrigation wells are not consistently required to report annual pumpage. Daily power-consumption and pump-discharge rates measured at 20 wells during the 1998 irrigation season and total power use at each well were used to estimate the amount of water, in feet of depth, applied to 20 alfalfa fields. These fields include about 10 percent of the total area, 36,700 acres, irrigated with ground water in the middle Humboldt River Basin. In 1998 an average of 2.0 feet of water was applied to 14 fields irrigated using center-pivot sprinkler systems, and an average of 2.6 feet of water was applied to 6 fields irrigated using wheel-line sprinkler systems. A similar approach was used to estimate the amount of water pumped at three wells using pumps powered by diesel engines. The two fields served by these three wells received 3.9 feet of water by flood irrigation during the 1998 irrigation season. The amount of water applied to the fields irrigated by center-pivot and wheel-line irrigation systems during the 1998 irrigation season was less than what would have been applied during a typical irrigation season because late winter and spring precipitation exceeded long-term monthly averages by as much as four times. As a result, the health of crops was affected by over-saturated soils, and most irrigation wells were only used sporadically in the first part of the irrigation season. Power consumption at 19 of the 20 wells in the 1994-97 irrigation seasons was 110 to 235 percent of the power consumption in the 1998 irrigation season. If the amount of water applied to fields during the 1998 irrigation season were adjusted to account for these differences in power consumption, the average amount of water applied to a field during a typical season using center-pivot and wheel-line sprinkler systems would be 3.1 feet and 3.7 feet, respectively. Total ground water pumped in the middle Humboldt River Basin during 1998 was about 298,000 acre-feet. This pumpage was distributed as follows: 78 percent for mining, 19 percent for irrigation, and 3 percent for industrial, municipal, and power plants combined. Mining pumpage is by far the largest source of ground-water use because several large gold mines have extended below local ground-water levels and the area around each mine must be dewatered in order to maintain a dry and workable mine. Total mining pumpage in 1998 was 233,000 acre-feet, of this total, 23,600 acre-feet was for consumptive use and 209,000 acre-feet was for dewatering eight mines. Excess water from the mines being dewatered was distributed as follows: 74,500 acre-feet was returned to aquifers by infiltration; 33,100 acre-feet was used for irrigation and for consumptive use at two mines and a power plant; 96,700 acre-feet was released to the Humboldt River or one of its tributaries; and 5,260 acre-feet was lost to evaporation.

Vulnerability of US and European electricity supply to climate change

NASA Astrophysics Data System (ADS)

van Vliet, Michelle T. H.; Yearsley, John R.; Ludwig, Fulco; Vögele, Stefan; Lettenmaier, Dennis P.; Kabat, Pavel

2012-09-01

In the United States and Europe, at present 91% and 78% (ref. ) of the total electricity is produced by thermoelectric (nuclear and fossil-fuelled) power plants, which directly depend on the availability and temperature of water resources for cooling. During recent warm, dry summers several thermoelectric power plants in Europe and the southeastern United States were forced to reduce production owing to cooling-water scarcity. Here we show that thermoelectric power in Europe and the United States is vulnerable to climate change owing to the combined impacts of lower summer river flows and higher river water temperatures. Using a physically based hydrological and water temperature modelling framework in combination with an electricity production model, we show a summer average decrease in capacity of power plants of 6.3-19% in Europe and 4.4-16% in the United States depending on cooling system type and climate scenario for 2031-2060. In addition, probabilities of extreme (>90%) reductions in thermoelectric power production will on average increase by a factor of three. Considering the increase in future electricity demand, there is a strong need for improved climate adaptation strategies in the thermoelectric power sector to assure futureenergy security.

Power and efficiency scaling of diode pumped Cr:LiSAF lasers: 770-1110 nm tuning range and frequency doubling to 387-463 nm.

PubMed

Demirbas, Umit; Baali, Ilyes

2015-10-15

We report significant average power and efficiency scaling of diode-pumped Cr:LiSAF lasers in continuous-wave (cw), cw frequency-doubled, and mode-locked regimes. Four single-emitter broad-area laser diodes around 660 nm were used as the pump source, which provided a total pump power of 7.2 W. To minimize thermal effects, a 20 mm long Cr:LiSAF sample with a relatively low Cr-concentration (0.8%) was used as the gain medium. In cw laser experiments, 2.4 W of output power, a slope efficiency of 50%, and a tuning range covering the 770-1110 nm region were achieved. Intracavity frequency doubling with beta-barium borate (BBO) crystals generated up to 1160 mW of blue power and a record tuning range in the 387-463 nm region. When mode locked with a saturable absorber mirror, the laser produced 195 fs pulses with 580 mW of average power around 820 nm at a 100.3 MHz repetition rate. The optical-to-optical conversion efficiency of the system was 33% in cw, 16% in cw frequency-doubled, and 8% in cw mode-locked regimes.

China power - thermal coal and clean coal technology export. Topical report

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

Binsheng Li

1996-12-31

China is the world`s fourth largest electric power producer, and is expected to surpass Japan within the next two years to become the third largest power producer. During the past 15 years, China`s total electricity generation more than tripled, increasing from about 300 TWh to about 1,000 TWh. Total installed generating capacity grew at an average of 8.2 percent per year, increasing from 66 to 214 GW. The share of China`s installed capacity in Asia increased from 21 to 31 percent. The Chinese government plans to continue China`s rapid growth rate in the power sector. Total installed capacity is plannedmore » to reach 300 GW by 2000, which will generate 1,400 TWh of electricity per year. China`s long-term power sector development is subject to great uncertainty. Under the middle scenario, total capacity is expected to reach 700 GW by 2015, with annual generation of 3,330 TWh. Under the low and high scenarios, total capacity will reach 527-1,005 GW by 2015. The high scenario representing possible demand. To achieve this ambitious scenario, dramatic policy changes in favor of power development are required; however, there is no evidence that such policy changes will occur at this stage. Even under the high scenario, China`s per capita annual electricity consumption would be only 3,000 kWh by 2015, less than half of the present per capita consumption for OECD countries. Under the low scenario, electricity shortages will seriously curb economic growth.« less

Predictors of cerebral microembolization during phased radiofrequency ablation of atrial fibrillation: analysis of biophysical parameters from the ablation generator.

PubMed

Nagy-Balo, Edina; Kiss, Alexandra; Condie, Catherine; Stewart, Mark; Edes, Istvan; Csanadi, Zoltan

2014-06-01

Pulmonary vein isolation with phased radiofrequency current and use of a pulmonary vein ablation catheter (PVAC) has recently been associated with a high incidence of clinically silent brain infarcts on diffusion-weighted magnetic resonance imaging and a high microembolic signal (MES) count detected by transcranial Doppler. The purpose of this study was to investigate the potential correlation between different biophysical parameters of energy delivery (ED) and MES generation during PVAC ablation. MES counts during consecutive PVAC ablations were recorded for each ED and time stamped for correlation with temperature, power, and impedance data from the GENius 14.4 generator. Additionally, catheter-tissue contact was characterized by the template deviation score, calculated by comparing the temperature curve with an ideal template representing good contact, and by the respiratory contact failure score, to quantify temperature variations indicative of intermittent contact due to respiration. A total of 834 EDs during 48 PVAC ablations were analyzed. A significant increase in MES count was associated with a lower average temperature, a temperature integral over 62°C, a higher average power, the total energy delivered, higher respiration and template deviation scores (P <.0001), and simultaneous ED to the most proximal and distal poles of the PVAC (P <.0001). MES generation during ablation is related to different indicators of poor electrode-tissue contact, the total power delivered, and the interaction between the most distal and the most proximal electrodes. Copyright © 2014. Published by Elsevier Inc.

Hydrodynamic trails produced by Daphnia: size and energetics.

PubMed

Wickramarathna, Lalith N; Noss, Christian; Lorke, Andreas

2014-01-01

This study focuses on quantifying hydrodynamic trails produced by freely swimming zooplankton. We combined volumetric tracking of swimming trajectories with planar observations of the flow field induced by Daphnia of different size and swimming in different patterns. Spatial extension of the planar flow field along the trajectories was used to interrogate the dimensions (length and volume) and energetics (dissipation rate of kinetic energy and total dissipated power) of the trails. Our findings demonstrate that neither swimming pattern nor size of the organisms affect the trail width or the dissipation rate. However, we found that the trail volume increases with increasing organism size and swimming velocity, more precisely the trail volume is proportional to the third power of Reynolds number. This increase furthermore results in significantly enhanced total dissipated power at higher Reynolds number. The biggest trail volume observed corresponds to about 500 times the body volume of the largest daphnids. Trail-averaged viscous dissipation rate of the swimming daphnids vary in the range of 1.8 x 10(-6) W/kg to 3.4 x 10(-6) W/kg and the observed magnitudes of total dissipated power between 1.3 x 10(-9) W and 1 x 10(-8) W, respectively. Among other zooplankton species, daphnids display the highest total dissipated power in their trails. These findings are discussed in the context of fluid mixing and transport by organisms swimming at intermediate Reynolds numbers.

²²⁶Ra, ²³²Th and ⁴⁰K radionuclides enhancement rate and dose assessment for residues of lignite-fired thermal power plants in Turkey.

PubMed

Parmaksiz, A; Arikan, P; Vural, M; Yeltepe, E; Tükenmez, I

2011-11-01

A total of 77 coal, slag and fly ash samples collected from six thermal power plants were measured by gamma-ray spectrometry. The average (226)Ra activity concentrations in coal, slag and fly ash were measured as 199.8±16.7, 380.3±21.8 and 431.5±29.0 Bq kg(-1), respectively. The average (232)Th activity concentrations in coal, slag and fly ash were measured as 32.0±2.4, 74.0±9.0 and 87.3±9.8 Bq kg(-1), respectively. The average (40)K activity concentrations in coal, slag and fly ash were found to be 152.8±12.1, 401.3±25.0 and 439.0±30.2 Bq kg(-1), respectively. The radium equivalent activities of samples varied from 147.6±8.5 to 1077.4±53.3 Bq kg(-1). The gamma and alpha index of one thermal power plant's fly ash were calculated to be 3.5 and 5 times higher than that of the reference values. The gamma absorbed dose rates were found to be higher than that of the average Earth's crust. The annual effective dose of residues measured in four thermal power plants were calculated higher than that of the permitted dose rate for public, i.e. 1 mSv y(-1).

Approximation algorithms for the min-power symmetric connectivity problem

NASA Astrophysics Data System (ADS)

Plotnikov, Roman; Erzin, Adil; Mladenovic, Nenad

2016-10-01

We consider the NP-hard problem of synthesis of optimal spanning communication subgraph in a given arbitrary simple edge-weighted graph. This problem occurs in the wireless networks while minimizing the total transmission power consumptions. We propose several new heuristics based on the variable neighborhood search metaheuristic for the approximation solution of the problem. We have performed a numerical experiment where all proposed algorithms have been executed on the randomly generated test samples. For these instances, on average, our algorithms outperform the previously known heuristics.

How much is the cost of multiple sclerosis--systematic literature review.

PubMed

Kolasa, Katarzyna

2013-01-01

In Poland, a data on MS costs is lacking. The systematic review of cost of illness studies was conducted to estimate the average annual cost of MS patient and its breakdown. The PubMed database was searched for relevant literature. Following search criteria were used: "multiple sclerosis", "costs", "cost of illness" and "disease burden". Articles written in English including total costs published 2002-2012 were included. In total 17 studies were classified. The costs were re-calculated into USD Purchasing Power Parity (PPP). The available approach from the literature was used for the cost breakdown presentation. The average patient was 47 years old with EDSS equals 4 and 13 years from the date of diagnosis. The average annual cost was 41 133 US$ PPP. The direct costs did not exceed 70% of total costs in any study. The pharmaceutical expenses were one of the most important contributors to the direct costs. Only 40% of patients were active on the labor market what translated into the loss of productivity and consequently an increase in total costs. The preformed systematic review revealed that multiple sclerosis imposes a huge economic burden on the healthcare system and society. It happens due to productivity loss and caregiver burden.

Antioxidant activity of honey supplemented with bee products.

PubMed

Juszczak, Lesław; Gałkowska, Dorota; Ostrowska, Małgorzata; Socha, Robert

2016-06-01

The aim of this work was to evaluate the influence of supplementation of multiflower honey with bee products on the phenolic compound content and on antioxidant activity. Average total phenolic and flavonoids contents in the multiflower honeys were 36.06 ± 10.18 mg GAE/100 g and 4.48 ± 1.69 mg QE/100 g, respectively. The addition of royal jelly did not affect significantly the phenolic compound content and antioxidant activity. Supplementation of honey with other bee products, i.e. beebread, propolis, pollen, resulted in significant increase in the total phenolic and flavonoids contents, and in antiradical activity and reducing power, with the largest effect found for addition of beebread. Significant linear correlations between the total phenolic and flavonoids contents and antiradical activity and reducing power were found.

Clustering and estimating fish fingerling abundance in a tidal river in close ploximity to a thermal power plant in Southern Thailand

NASA Astrophysics Data System (ADS)

Chesoh, S.; Lim, A.; Luangthuvapranit, C.

2018-04-01

This study aimed to cluster and to quantify the wild-caught fingerlings nearby thermal power plant. Samples were monthly collected by bongo nets from four upstream sites of the Na Thap tidal river in Thailand from 2008 to 2013. Each caught species was identified, counted and calculated density in term of individuals per 1,000 cubic meters. A total of 45 aquatic animal fingerlings was commonly trapped in the average density of 2,652 individuals per 1,000 cubic meters of water volume (1,235–4,570). The results of factor analysis revealed that factor 1 was represented by the largest group of freshwater fish species, factors 2 represented a medium-sized group of mesohaline species, factor 3 represented several brackish species and factor 4 was a few euryhaline species. All four factor reached maximum levels during May to October. Total average numbers of fish fingerling caught at the outflow showed greater than those of other sampling sites. The impact of heated pollution from power plant effluents did not clearly detected. Overall water quality according the Thailand Surface Water Quality Standards Coastal tidal periodic and seasonal runoff phenomena exhibit influentially factors. Continuous ecological monitoring is strongly recommended.

Solar Pumped Solid State Lasers for Space Solar Power: Experimental Path

NASA Technical Reports Server (NTRS)

Fork, Richard L.; Carrington, Connie K.; Walker, Wesley W.; Cole, Spencer T.; Green, Jason J. A.; Laycock, Rustin L.

2003-01-01

We outline an experimentally based strategy designed to lead to solar pumped solid state laser oscillators useful for space solar power. Our method involves solar pumping a novel solid state gain element specifically designed to provide efficient conversion of sunlight in space to coherent laser light. Kilowatt and higher average power is sought from each gain element. Multiple such modular gain elements can be used to accumulate total average power of interest for power beaming in space, e.g., 100 kilowatts and more. Where desirable the high average power can also be produced as a train of pulses having high peak power (e.g., greater than 10(exp 10 watts). The modular nature of the basic gain element supports an experimental strategy in which the core technology can be validated by experiments on a single gain element. We propose to do this experimental validation both in terrestrial locations and also on a smaller scale in space. We describe a terrestrial experiment that includes diagnostics and the option of locating the laser beam path in vacuum environment. We describe a space based experiment designed to be compatible with the Japanese Experimental Module (JEM) on the International Space Station (ISS). We anticipate the gain elements will be based on low temperature (approx. 100 degrees Kelvin) operation of high thermal conductivity (k approx. 100 W/cm-K) diamond and sapphire (k approx. 4 W/cm-K). The basic gain element will be formed by sequences of thin alternating layers of diamond and Ti:sapphire with special attention given to the material interfaces. We anticipate this strategy will lead to a particularly simple, robust, and easily maintained low mass modelocked multi-element laser oscillator useful for space solar power.

Detecting the response of fish assemblages to stream restoration: Effects of different sampling designsf

USGS Publications Warehouse

Baldigo, Barry P.; Warren, D.R.

2008-01-01

Increased trout production within limited stream reaches is a popular goal for restoration projects, yet investigators seldom monitor, assess, or publish the associated effects on fish assemblages. Fish community data from a total of 40 surveys at restored and reference reaches in three streams of the Catskill Mountains, New York, were analyzed a posteriori to determine how the ability to detect significant changes in biomass of brown trout Salmo trutta, all salmonids, or the entire fish community differs with effect size, number of streams assessed, process used to quantify the index response, and number of replicates collected before and after restoration. Analyses of statistical power (probability of detecting a meaningful difference or effect) and integrated power (average power over all possible ??-values) were combined with before-after, control-impact analyses to assess the effectiveness of alternate sampling and analysis designs. In general, the more robust analyses indicated that biomass of brown trout and salmonid populations increased significantly in restored reaches but that the net increases (relative to the reference reach) were significant only at two of four restored reaches. Restoration alone could not account for the net increases in total biomass of fish communities. Power analyses generally showed that integrated power was greater than 0.95 when (1) biomass increases were larger than 5.0 g/m2, (2) the total number of replicates ranged from 4 to 8, and (3) coefficients of variation (CVs) for responses were less than 40%. Integrated power was often greater than 0.95 for responses as low as 1.0 g/m2 if the response CVs were less than 30%. Considering that brown trout, salmonid, and community biomass increased by 2.99 g/m2 on average (SD= 1.17 g/m2) in the four restored reaches, use of two to three replicates both before and after restoration would have an integrated power of about 0.95 and would help detect significant changes in fish biomass under similar situations. ?? Copyright by the American Fisheries Society 2008.

A Quantitative Assessment of Utility Reporting Practices for Reporting Electric Power Distribution Events

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

Hamachi La Commare, Kristina

Metrics for reliability, such as the frequency and duration of power interruptions, have been reported by electric utilities for many years. This study examines current utility practices for collecting and reporting electricity reliability information and discusses challenges that arise in assessing reliability because of differences among these practices. The study is based on reliability information for year 2006 reported by 123 utilities in 37 states representing over 60percent of total U.S. electricity sales. We quantify the effects that inconsistencies among current utility reporting practices have on comparisons of System Average Interruption Duration Index (SAIDI) and System Average Interruption Frequency Indexmore » (SAIFI) reported by utilities. We recommend immediate adoption of IEEE Std. 1366-2003 as a consistent method for measuring and reporting reliability statistics.« less

Current status of radiological protection at nuclear power stations in Japan.

PubMed

Suzuki, Akira; Hori, Shunsuke

2011-07-01

The radiation dose to workers at nuclear power stations (NPSs) in Japan was drastically reduced between the late-1970s and the early-1990s by continuous dose-reduction programmes. The total collective dose of radiation workers in FY 2008 was 84.04 person Sv, while the average collective dose was 1.5 person Sv per reactor. The average annual individual dose was 1.1 mSv and the maximum annual individual dose was 19.5 mSv. These values are sufficiently lower than the regulatory dose limits. Radioactive effluent released from NPSs is already so trivial that additional protective measures will not be necessary. Experience in radiation protection at NPSs has been accumulated over 40 y and will be very useful in establishing a rational radiation control system in the future.

40 CFR 60.102a - Emissions limitations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... precipitator: (i) The 3-hour rolling average total power and secondary current to the entire system must not... provided in paragraph (f)(3), each owner or operator of an affected sulfur recovery plant shall comply with... plant with a capacity greater than 20 long tons per day (LTD): (i) For a sulfur recovery plant with an...

40 CFR 60.102a - Emissions limitations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... precipitator: (i) The 3-hour rolling average total power and secondary current to the entire system must not... provided in paragraph (f)(3), each owner or operator of an affected sulfur recovery plant shall comply with... plant with a capacity greater than 20 long tons per day (LTD): (i) For a sulfur recovery plant with an...

40 CFR 60.102a - Emissions limitations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... precipitator: (i) The 3-hour rolling average total power and secondary current to the entire system must not... provided in paragraph (f)(3), each owner or operator of an affected sulfur recovery plant shall comply with... plant with a capacity greater than 20 long tons per day (LTD): (i) For a sulfur recovery plant with an...

40 CFR 60.266 - Test methods and procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... effluent gas from exhaust stream “i”, dscm/hr (dscf/hr). P=average furnace power input, MW. K=conversion....8, the owner or operator shall not allow gaseous diluents to be added to the effluent gas stream after the fabric in an open pressurized fabric filter collector unless the total gas volume flow from...

Ab initio phasing by molecular averaging in real space with new criteria: application to structure determination of a betanodavirus.

PubMed

Yoshimura, Masato; Chen, Nai Chi; Guan, Hong Hsiang; Chuankhayan, Phimonphan; Lin, Chien Chih; Nakagawa, Atsushi; Chen, Chun Jung

2016-07-01

Molecular averaging, including noncrystallographic symmetry (NCS) averaging, is a powerful method for ab initio phase determination and phase improvement. Applications of the cross-crystal averaging (CCA) method have been shown to be effective for phase improvement after initial phasing by molecular replacement, isomorphous replacement, anomalous dispersion or combinations of these methods. Here, a two-step process for phase determination in the X-ray structural analysis of a new coat protein from a betanodavirus, Grouper nervous necrosis virus, is described in detail. The first step is ab initio structure determination of the T = 3 icosahedral virus-like particle using NCS averaging (NCSA). The second step involves structure determination of the protrusion domain of the viral molecule using cross-crystal averaging. In this method, molecular averaging and solvent flattening constrain the electron density in real space. To quantify these constraints, a new, simple and general indicator, free fraction (ff), is introduced, where ff is defined as the ratio of the volume of the electron density that is freely changed to the total volume of the crystal unit cell. This indicator is useful and effective to evaluate the strengths of both NCSA and CCA. Under the condition that a mask (envelope) covers the target molecule well, an ff value of less than 0.1, as a new rule of thumb, gives sufficient phasing power for the successful construction of new structures.

Power Management Integrated Circuit for Indoor Photovoltaic Energy Harvesting System

NASA Astrophysics Data System (ADS)

Jain, Vipul

In today's world, power dissipation is a main concern for battery operated mobile devices. Key design decisions are being governed by power rather than area/delay because power requirements are growing more stringent every year. Hence, a hybrid power management system is proposed, which uses both a solar panel to harvest energy from indoor lighting and a battery to power the load. The system tracks the maximum power point of the solar panel and regulates the battery and microcontroller output load voltages through the use of an on-chip switched-capacitor DC-DC converter. System performance is verified through simulation at the 180nm technology node and is made to be integrated on-chip with 0.25 second startup time, 79% efficiency, --8/+14% ripple on the load, an average 1micro A of quiescent current (3.7micro W of power) and total on-chip area of 1.8mm2 .

Fragmentation and dusting of large kidney stones using compact, air-cooled, high peak power, 1940-nm, Thulium fiber laser

NASA Astrophysics Data System (ADS)

Hardy, Luke A.; Gonzalez, David A.; Irby, Pierce B.; Fried, Nathaniel M.

2018-02-01

Previous Thulium fiber laser lithotripsy (TFL) studies were limited to a peak power of 70 W (35 mJ / 500 μs), requiring operation in dusting mode with low pulse energy (35 mJ) and high pulse rate (300 Hz). In this study, a novel, compact, air-cooled, TFL capable of operating at up to 500 W peak power, 50 W average power, and 2000 Hz, was tested. The 1940-nm TFL was used with pulse duration (500 μs), average power (10 W), and fiber (270- μm-core) fixed, while pulse energy and pulse rate were changed. A total of 23 large uric acid (UA) stones and 16 large calcium oxalate monohydrate (COM) stones were each separated into 3 modes (Group 1-"Dusting"- 33mJ/300Hz; Group 2-"Fragmentation"-200mJ/50Hz; Group 3-"Dual mode"-Fragmentation then Dusting). The fiber was held manually in contact with stone on a 2-mm-mesh sieve submerged in a flowing saline bath. UA ablation rates were 2.3+/-0.8, 2.3+/-0.2, and 4.4+/-0.8 mg/s and COM ablation rates were 0.4+/-0.1, 1.0+/-0.1, and 0.9+/-0.4 mg/s, for Groups 1, 2, and 3. Dual mode provided 2x higher UA ablation rates than other modes. COM ablation threshold is 3x higher than UA, so dusting provided lower COM ablation rates than other modes. Future studies will explore higher average laser power than 10 W for rapid TFL ablation of large stones.

Evaluation of nutritional quality and antioxidant potential of pigeonpea genotypes.

PubMed

Sekhon, Japjot; Grewal, Satvir Kaur; Singh, Inderjit; Kaur, Jagmeet

2017-10-01

Three released cultivars, forty four advance breeding lines and three wild species of pigeonpea ( Cajanus cajan L. Millsp) were evaluated for nutritional, antinutritional traits and antioxidant potential so as to identify promising genotypes. The average content of total soluble sugars, starch and total soluble proteins was found to be 43.66, 360.51 and 204.54 mg/g, respectively. Antioxidant potential in terms of free radical scavenging activity (DPPH), ferric reducing antioxidant power (FRAP), reducing power, hydroxyl radical scavenging activity and superoxide anion radical scavenging activity was estimated. The diversity was observed in genotypes with all the traits. AL 1960, AL 2000, AL 2009 and AL 2046 had high total soluble proteins, medium antinutritional factors and good antioxidant potential. AL 201, AL 1931, AL 1932, AL 1960, AL 2046, AL 2049 and AL 2060 had good nutritional value as protein and starch content ranged from 20 to 23 and 42 to 52%, respectively. Wild species C. scarabaeoides 1CP15683/W15 had lower carbohydrates, proteins, and antinutritional traits while high antioxidant potential due to high total phenols, DPPH, FRAP and reducing power. The diversity observed in genotypes with all the traits could be further used to develop nutritionally important genotypes.

Estimating radiofrequency power deposition in body NMR imaging.

PubMed

Bottomley, P A; Redington, R W; Edelstein, W A; Schenck, J F

1985-08-01

Simple theoretical estimates of the average, maximum, and spatial variation of the radiofrequency power deposition (specific absorption rate) during hydrogen nuclear magnetic resonance imaging are deduced for homogeneous spheres and for cylinders of biological tissue with a uniformly penetrating linear rf field directed axially and transverse to the cylindrical axis. These are all simple scalar multiples of the expression for the cylinder in an axial field published earlier (Med. Phys. 8, 510 (1981]. Exact solutions for the power deposition in the cylinder with axial (Phys. Med. Biol. 23, 630 (1978] and transversely directed rf field are also presented, and the spatial variation of power deposition in head and body models is examined. In the exact models, the specific absorption rates decrease rapidly and monotonically with decreasing radius despite local increases in rf field amplitude. Conversion factors are provided for calculating the power deposited by Gaussian and sinc-modulated rf pulses used for slice selection in NMR imaging, relative to rectangular profiled pulses. Theoretical estimates are compared with direct measurements of the total power deposited in the bodies of nine adult males by a 63-MHz body-imaging system with transversely directed field, taking account of cable and NMR coil losses. The results for the average power deposition agree within about 20% for the exact model of the cylinder with axial field, when applied to the exposed torso volume enclosed by the rf coil. The average values predicted by the simple spherical and cylindrical models with axial fields, the exact cylindrical model with transverse field, and the simple truncated cylinder model with transverse field were about two to three times that measured, while the simple model consisting of an infinitely long cylinder with transverse field gave results about six times that measured. The surface power deposition measured by observing the incremental power as a function of external torso radius was comparable to the average value. This is consistent with the presence of a variable thickness peripheral adipose layer which does not substantially increase surface power deposition with increasing torso radius. The absence of highly localized intensity artifacts in 63-MHz body images does not suggest anomalously intense power deposition at localized internal sites, although peak power is difficult to measure.

The Diamond Window with Boron-Doped Layers for the Output of Microwave Radiation at High Peak and Average Power Levels

NASA Astrophysics Data System (ADS)

Ivanov, O. A.; Kuzikov, S. V.; Vikharev, A. A.; Vikharev, A. L.; Lobaev, M. A.

2017-10-01

We propose a novel design of the barrier window for the output of microwave radiation at high peak and average power levels. A window based on a plate of polycrystalline CVD diamond with thin (nanometer-thick) boron-doped layers with increased conductivity is considered. Such a window, which retains the low radiation loss due to the small total thickness of the conductive layers and the high thermal conductivity inherent in diamond, prevents accumulation of a static charge on its surface, on the one hand, and allows one to produce a static electric field on the surface of the doped layer, which impedes the development of a multipactor discharge, on the other hand. In this case, a high level of the power of the transmitted radiation and a large passband width are ensured by choosing the configuration of the field in the form of a traveling wave inside the window.

Humid free efficient solar panel

NASA Astrophysics Data System (ADS)

Panjwani, Manoj Kumar; Panjwani, Suresh Kumar; Mangi, Fareed Hussain; Khan, Danish; Meicheng, Li

2017-09-01

The paper examines the impact of the humidity on the Solar panels which makes a space for the drastic variation in the power generated and makes the device less efficient. Humidity readily affects the efficiency of the solar cells and creates a minimal layer of water on its surface. It also decreases the efficiency by 10-20% of the total power output produced. Moreover, to handle this issue, all around characterized measures are required to be taken to guarantee the smooth working of the solar panels utilized in humid areas. In connection with this issue, Karachi, the biggest city of Pakistan which is located near the costal line touching Arabian Sea, was taken as a reference city to measure the humidity range. In Karachi, the average humidity lies between 25-70% (as per Pakistan Meteorological Department PMD), that indirectly leads in decreasing power acquired from a Solar Panel and develops various complexities for the solar system. The system on average experiences stability issues, such as those of power fluctuations etc., due to which, the whole solar system installed observes abnormal variations in acquired power. Silica Gel was used as a desiccant material in order to assure dryness over the solar panel. More than four experiments were conducted with the usage of water absorbent to improve the efficiency and to make system more power efficient.

A mobile communication system providing integrated voice/data services over power limited satellite channels

NASA Astrophysics Data System (ADS)

Bose, Sanjay K.; Gordon, J. J.

The modeling and analysis of a system providing integrated voice/data services to mobile terminals over a power-limited satellite channel are discussed. The mobiles use slotted Aloha random access to send requests for channel assignments to a central station. For successful requests, the actual transmission of voice/data within a call is done using the channel assigned for this purpose by the central station. The satellite channel is assumed to be power limited. Taking into account the known burstiness of voice sources (which use a voice-activated switch), the central station overassigns channels so that the average total power is below the power limit of the satellite transponder. The performance of this model is analyzed. Certain simple, static control strategies for improving performance are also proposed.

Pressure and heat-transfer distributions in a simulated wing-elevon cove with variable leakage at a free-stream Mach number of 6.9

NASA Technical Reports Server (NTRS)

Deveikis, W. D.; Bartlett, W.

1978-01-01

An experimental aerodynamic heating investigation was conducted to determine effects of hot boundary-layer ingestion into the cove on the windward surface between a wing and elevon for cove seal leak areas nominally between 0 and 100 percent of cove entrance area. Pressure and heating-rate distributions were obtained on the wing and elevon surfaces and on the cove walls of a full-scale model that represented a section of the cove region on the space shuttle orbiter. Data were obtained for both attached and separated turbulent boundary layers upstream of the unswept cove entrance. Average free-stream Mach number was 6.9, average free-stream unit Reynolds numbers were 1.31 x 10 to the 6th power and 4.40 x 10 to the 6th power per meter (0.40 x 10 to the 6th power and 1.34 x 10 to the 6th power per foot), and average total temperature was 1888 K (3400 R). Cove pressures and heating rates varied as a function of seal leak area independent of leak aspect ratio. Although cove heating rates for attached flow did not appear intolerable, it was postulated that convective heating in the cove may increase with time. For separated flow, the cove environment was considered too severe for unprotected interior structures of control surfaces.

Efficacy of isokinetic exercise on functional capacity and pain in patellofemoral pain syndrome.

PubMed

Alaca, Ridvan; Yilmaz, Bilge; Goktepe, A Salim; Mohur, Haydar; Kalyon, Tunc Alp

2002-11-01

To assess the effect of an isokinetic exercise program on symptoms and functions of patients with patellofemoral pain syndrome. A total of 22 consecutive patients with the complaint of anterior knee pain who met the inclusion criteria were recruited to assess the efficacy of isokinetic exercise on functional capacity, isokinetic parameters, and pain scores in patients with patellofemoral pain syndrome. A total of 37 knees were examined. Six-meter hopping, three-step hopping, and single-limb hopping course tests were performed for each patient with the measurements of the Lysholm scale and visual analog scale. Tested parameters were peak torque, total work, average power, and endurance ratios. Statistical analyses revealed that at the end of the 6-wk treatment period, functional and isokinetic parameters improved significantly, as did pain scores. There was not statistically significant correlation between different groups of parameters. The isokinetic exercise treatment program used in this study prevented the extensor power loss due to patellofemoral pain syndrome, but the improvement in the functional capacity was not correlated with the gained power.

2014 Wind Technologies Market Report

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

Wiser, R.; Bolinger, M.

According to the 2014 Wind Technologies Market Report, total installed wind power capacity in the United States grew at a rate of eight percent in 2014, bringing the United States total installed capacity to nearly 66 gigawatts (GW), which ranks second in the world and meets 4.9 percent of U.S. end-use electricity demand in an average year. In total, 4,854 MW of new wind energy capacity were installed in the United States in 2014. The 2014 Wind Technologies Market Report also finds that wind energy prices are at an all-time low and are competitive with wholesale power prices and traditionalmore » power sources across many areas of the United States. Additionally, a new trend identified by the 2014 Wind Technologies Market Report shows utility-scale turbines with larger rotors designed for lower wind speeds have been increasingly deployed across the country in 2014. The findings also suggest that the success of the U.S. wind industry has had a ripple effect on the American economy, supporting 73,000 jobs related to development, siting, manufacturing, transportation, and other industries.« less

Cancer incidence in northern Sweden before and after the Chernobyl nuclear power plant accident.

PubMed

Alinaghizadeh, Hassan; Tondel, Martin; Walinder, Robert

2014-08-01

Sweden received about 5 % of the total release of (137)Cs from the Chernobyl nuclear power plant accident in 1986. The distribution of the fallout mainly affected northern Sweden, where some parts of the population could have received an estimated annual effective dose of 1-2 mSv per year. It is disputed whether an increased incidence of cancer can be detected in epidemiological studies after the Chernobyl nuclear power plant accident outside the former Union of Soviet Socialist Republics. In the present paper, a possible exposure-response pattern between deposition of (137)Cs and cancer incidence after the Chernobyl nuclear power plant accident was investigated in the nine northernmost counties of Sweden (2.2 million inhabitants in 1986). The activity of (137)Cs from the fallout maps at 1986 was used as a proxy for the received dose of ionizing radiation. Diagnoses of cancer (ICD-7 code 140-209) from 1980 to 2009 were received from the Swedish Cancer Registry (273,222 cases). Age-adjusted incidence rate ratios, stratified by gender, were calculated with Poisson regression in two closed cohorts of the population in the nine counties 1980 and 1986, respectively. The follow-up periods were 1980-1985 and 1986-2009, respectively. The average surface-weighted deposition of (137)Cs at three geographical levels; county (n = 9), municipality (n = 95) and parish level (n = 612) was applied for the two cohorts to study the pre- and the post-Chernobyl periods separately. To analyze time trends, the age-standardized total cancer incidence was calculated for the general Swedish population and the population in the nine counties. Joinpoint regression was used to compare the average annual percent change in the general population and the study population within each gender. No obvious exposure-response pattern was seen in the age-adjusted total cancer incidence rate ratios. A spurious association between fallout and cancer incidence was present, where areas with the lowest incidence of cancer before the accident coincidentally had the lowest fallout of (137)Cs. Increasing the geographical resolution of exposure from nine county averages to 612 parish averages resulted in a two to three times higher value of variance in the regression model. There was a secular trend with an increase in age-standardized incidence of cancer in both genders from 1980 to 2009, but significant only in females. This trend was stronger and statistically significant for both genders in the general Swedish population compared to the nine counties. In conclusion, using both high quality cancer registry data and high resolution exposure maps of (137)Cs deposition, it was not possible to distinguish an effect of (137)Cs on cancer incidence after the Chernobyl nuclear power plant accident in Sweden.

75 FR 52936 - Energy Exchange, Inc.; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-30

... and Fairmont) and two existing, 36- and 54- inch diameter steel pipelines; (2) three proposed powerhouses, each to contain a 0.37-megawatt-(MW) turbine-generating unit, with a total capacity of 1.11 MW...-in point of a local power company grid system. The project would produce an estimated average annual...

High pumping-power fiber combiner for double-cladding fiber lasers and amplifiers

NASA Astrophysics Data System (ADS)

Zheng, Jinkun; Zhao, Wei; Zhao, Baoyin; Li, Zhe; Chang, Chang; Li, Gang; Gao, Qi; Ju, Pei; Gao, Wei; She, Shengfei; Wu, Peng; Hou, Chaoqi; Li, Weinan

2018-03-01

A high pumping-power fiber combiner for backward pumping configurations is fabricated and demonstrated by manufacturing process refinement. The pump power handling capability of every pump fiber can extend to 600 W, corresponding to the average pump coupling efficiency of 94.83%. Totally, 2.67-kW output power with the beam quality factor M2 of 1.41 was obtained, using this combiner in the fiber amplifier experimental setup. In addition, the temperature of the splicing region was less than 50.0°C in the designed combiner under the action of circulating cooling water. The experimental results prove that the designed combiner is a promising integrated all-fiber device for multikilowatt continuous-wave fiber laser with excellent beam quality.

Numerical modeling and analytical evaluation of light absorption by gold nanostars

NASA Astrophysics Data System (ADS)

Zarkov, Sergey; Akchurin, Georgy; Yakunin, Alexander; Avetisyan, Yuri; Akchurin, Garif; Tuchin, Valery

2018-04-01

In this paper, the regularity of local light absorption by gold nanostars (AuNSts) model is studied by method of numerical simulation. The mutual diffraction influence of individual geometric fragments of AuNSts is analyzed. A comparison is made with an approximate analytical approach for estimating the average bulk density of absorbed power and total absorbed power by individual geometric fragments of AuNSts. It is shown that the results of the approximate analytical estimate are in qualitative agreement with the numerical calculations of the light absorption by AuNSts.

Contribution of the crystalline lens gradient refractive index to the accommodation amplitude in non-human primates: in vitro studies.

PubMed

Maceo, Bianca M; Manns, Fabrice; Borja, David; Nankivil, Derek; Uhlhorn, Stephen; Arrieta, Esdras; Ho, Arthur; Augusteyn, Robert C; Parel, Jean-Marie

2011-11-30

The purpose of this study was to determine the contribution of the gradient refractive index to the change in lens power in hamadryas baboon and cynomolgus monkey lenses during simulated accommodation in a lens stretcher. Thirty-six monkey lenses (1.4-14.1 years) and twenty-five baboon lenses (1.8-28.0 years) were stretched in discrete steps. At each stretching step, the lens back vertex power was measured and the lens cross-section was imaged with optical coherence tomography. The radii of curvature for the lens anterior and posterior surfaces were calculated for each step. The power of each lens surface was determined using refractive indices of 1.365 for the outer cortex and 1.336 for the aqueous. The gradient contribution was calculated by subtracting the power of the surfaces from the measured lens power. In all lenses, the contribution of the surfaces and gradient increased linearly with the amplitude of accommodation. The gradient contributes on average 65 ± 3% for monkeys and 66 ± 3% for baboons to the total power change during accommodation. When expressed in percent of the total power change, the relative contribution of the gradient remains constant with accommodation and age in both species. These findings are consistent with Gullstrand's intracapsular theory of accommodation.

Ab initio phasing by molecular averaging in real space with new criteria: application to structure determination of a betanodavirus

PubMed Central

Yoshimura, Masato; Chen, Nai-Chi; Guan, Hong-Hsiang; Chuankhayan, Phimonphan; Lin, Chien-Chih; Nakagawa, Atsushi; Chen, Chun-Jung

2016-01-01

Molecular averaging, including noncrystallographic symmetry (NCS) averaging, is a powerful method for ab initio phase determination and phase improvement. Applications of the cross-crystal averaging (CCA) method have been shown to be effective for phase improvement after initial phasing by molecular replacement, isomorphous replacement, anomalous dispersion or combinations of these methods. Here, a two-step process for phase determination in the X-ray structural analysis of a new coat protein from a betanodavirus, Grouper nervous necrosis virus, is described in detail. The first step is ab initio structure determination of the T = 3 icosahedral virus-like particle using NCS averaging (NCSA). The second step involves structure determination of the protrusion domain of the viral molecule using cross-crystal averaging. In this method, molecular averaging and solvent flattening constrain the electron density in real space. To quantify these constraints, a new, simple and general indicator, free fraction (ff), is introduced, where ff is defined as the ratio of the volume of the electron density that is freely changed to the total volume of the crystal unit cell. This indicator is useful and effective to evaluate the strengths of both NCSA and CCA. Under the condition that a mask (envelope) covers the target molecule well, an ff value of less than 0.1, as a new rule of thumb, gives sufficient phasing power for the successful construction of new structures. PMID:27377380

The independent effects of speed and propulsive force on joint power generation in walking

PubMed Central

Browne, Michael G.; Franz, Jason R.

2017-01-01

Walking speed is modulated using propulsive forces (FP) during push-off and both preferred speed and FP decrease with aging. However, even prior to walking slower, reduced FP may be accompanied by potentially unfavorable changes in joint power generation. For example, compared to young adults, older adults exhibit a redistribution of mechanical power generation from the propulsive plantarflexor muscles to more proximal muscles acting across the knee and hip. Here, we used visual biofeedback based on real-time FP measurements to decouple and investigate the interaction between joint-level coordination, whole-body FP, and walking speed. 12 healthy young subjects walked on a dual-belt instrumented treadmill at a range of speeds (0.9 – 1.3 m/s). We immediately calculated the average FP from each speed. Subjects then walked at 1.3 m/s while completing a series of biofeedback trials with instructions to match their instantaneous FP to their averaged FP from slower speeds. Walking slower decreased FP and total positive joint work with little effect on relative joint-level contributions. Conversely, subjects walked at a constant speed with reduced FP, not by reducing total positive joint work, but by redistributing the mechanical demands of each step from the plantarflexor muscles during push-off to more proximal leg muscles during single support. Interestingly, these naturally emergent joint- and limb-level biomechanical changes, in the absence of neuromuscular constraints, resemble those due to aging. Our findings provide important reference data to understand the presumably complex interactions between joint power generation, whole-body FP, and walking speed in our aging population. PMID:28262285

Effect of Red Bull energy drink on repeated Wingate cycle performance and bench-press muscle endurance.

PubMed

Forbes, Scott C; Candow, Darren G; Little, Jonathan P; Magnus, Charlene; Chilibeck, Philip D

2007-10-01

The purpose of this study was to determine the effects of Red Bull energy drink on Wingate cycle performance and muscle endurance. Healthy young adults (N = 15, 11 men, 4 women, 21 +/- 5 y old) participated in a crossover study in which they were randomized to supplement with Red Bull (2 mg/kg body mass of caffeine) or isoenergetic, isovolumetric, noncaffeinated placebo, separated by 7 d. Muscle endurance (bench press) was assessed by the maximum number of repetitions over 3 sets (separated by 1-min rest intervals) at an intensity corresponding to 70% of baseline 1-repetition maximum. Three 30-s Wingate cycling tests (load = 0.075 kp/kg body mass), with 2 min recovery between tests, were used to assess peak and average power output. Red Bull energy drink significantly increased total bench-press repetitions over 3 sets (Red Bull = 34 +/- 9 vs. placebo = 32 +/- 8, P %%%lt; 0.05) but had no effect on Wingate peak or average power (Red Bull = 701 +/- 124 W vs. placebo = 700 +/- 132 W, Red Bull = 479 +/- 74 W vs. placebo = 471 +/- 74 W, respectively). Red Bull energy drink significantly increased upper body muscle endurance but had no effect on anaerobic peak or average power during repeated Wingate cycling tests in young healthy adults.

Automotive Stirling Engine Development Program Mod I Stirling engine development

NASA Technical Reports Server (NTRS)

Simetkosky, M. A.

1983-01-01

The development of the Mod I 4-cylinder automotive Stirling engine is discussed and illustrated with drawings, block diagrams, photographs, and graphs and tables of preliminary test data. The engine and its drive, cold-engine, hot-engine, external-heat, air/fuel, power-control, electronic-control, and auxiliary systems are characterized. Performance results from a total of 1900 h of tests on 4 prototype engines include average maximum efficiency (at 2000 rpm) 34.5 percent and maximum output power 54.4 kW. The modifications introduced in an upgraded version of the Mod I are explained; this engine has maximum efficiency 40.4 percent and maximum power output 69.2 kW.

Total Ownership Cost Reduction Case Study: AEGIS Microwave Power Tubes

DTIC Science & Technology

2006-05-31

processes. The center would also maintain crucial capabilities and knowledge required for test and evaluation, Logistics, and for certain...of the research presented herein. Reproduction of all or part of this report is authorized. The report was prepared by...burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching

Population dose commitments due to radioactive releases from nuclear-power-plant sites in 1978

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

Peloquin, R.A.; Schwab, J.D.; Baker, D.A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1978. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving variousmore » average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways ranged from a high of 200 person-rem to a low of 0.0004 person-rem with an arithmetic mean of 14 person-rem. The total population dose for allsites was estimated at 660 person-rem for the 93 million people considered at risk. The average individual dose commitment from all pathways on a site basis ranged from a low of 3 x 10/sup -6/ mrem to a high of 0.08 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.« less

Population dose commitments due to radioactive releases from Nuclear-Power-Plant Sites in 1979

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

Baker, D.A.; Peloquin, R.A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1979. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving variousmore » average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways ranged from a high of 1300 person-rem to a low of 0.0002 person-rem with an arithmetic mean of 38 person-rem. The total population dose for all sites was estimated at 1800 person-rem for the 94 million people considered at risk. The average individual dose commitment from all pathways on a site basis ranged from a low of 2 x 10/sup -6/ mrem to a high of 0.7 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.« less

Population Dose Commitments Due to Radioactive Releases from Nuclear Power Plant Sites in 1977

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

Baker, D. A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1977. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ, Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving variousmore » average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways ranged from a high of 220 person-rem to a low of 0.003 person-rem with an arithmetic mean of 16 person-rem. The total population dose for all sites was estimated at 700 person-rem for the 92 million people considered at risk. The average individual dose commitment from all pathways on a site basis ranged from a low of 2 x 10{sup -5} mrem to a high of 0.1 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.« less

In situ LTE exposure of the general public: Characterization and extrapolation.

PubMed

Joseph, Wout; Verloock, Leen; Goeminne, Francis; Vermeeren, Günter; Martens, Luc

2012-09-01

In situ radiofrequency (RF) exposure of the different RF sources is characterized in Reading, United Kingdom, and an extrapolation method to estimate worst-case long-term evolution (LTE) exposure is proposed. All electric field levels satisfy the International Commission on Non-Ionizing Radiation Protection (ICNIRP) reference levels with a maximal total electric field value of 4.5 V/m. The total values are dominated by frequency modulation (FM). Exposure levels for LTE of 0.2 V/m on average and 0.5 V/m maximally are obtained. Contributions of LTE to the total exposure are limited to 0.4% on average. Exposure ratios from 0.8% (LTE) to 12.5% (FM) are obtained. An extrapolation method is proposed and validated to assess the worst-case LTE exposure. For this method, the reference signal (RS) and secondary synchronization signal (S-SYNC) are measured and extrapolated to the worst-case value using an extrapolation factor. The influence of the traffic load and output power of the base station on in situ RS and S-SYNC signals are lower than 1 dB for all power and traffic load settings, showing that these signals can be used for the extrapolation method. The maximal extrapolated field value for LTE exposure equals 1.9 V/m, which is 32 times below the ICNIRP reference levels for electric fields. Copyright © 2012 Wiley Periodicals, Inc.

Poor correlation between handgrip strength and isokinetic performance of knee flexor and extensor muscles in community-dwelling elderly women.

PubMed

Felicio, Diogo Carvalho; Pereira, Daniele Sirineu; Assumpção, Alexandra Miranda; de Jesus-Moraleida, Fabianna Resende; de Queiroz, Barbara Zille; da Silva, Juscelio Pereira; de Brito Rosa, Naysa Maciel; Dias, João Marcos Domingues; Pereira, Leani Souza Máximo

2014-01-01

To investigate the correlation between handgrip strength and performance of knee flexor and extensor muscles determined using an isokinetic dynamometer in community-dwelling elderly women. This was a cross-sectional study. Sample selection for the study was made by convenience, and 221 (71.07 ± 4.93 years) community-dwelling elderly women were included. Knee flexor and extensor muscle performance was measured using an isokinetic dynamometer Biodex System 3 Pro. The isokinetic variables chosen for analysis were peak torque, peak torque/bodyweight, total work/bodyweight, total work, average power, and agonist/antagonist ratio at the angular velocities of 60°/s and 180°/s. Assessment of handgrip strength was carried out using the Jamar dynamometer. Spearman's correlation coefficient was calculated to identify intervariable correlations. Only knee flexor peak torque (60°/s) and average power (60°/s), and knee extensor peak torque (180°/s) and total work (180°/s) were significantly (P < 0.05), yet poorly, correlated with handgrip strength (r < 0.30). The majority of analyses did not show any correlation between variables assessed by isokinetic dynamometer and handgrip dynamometer. Caution is required when generalizing handgrip strength as a predictor of global muscle strength in community-dwelling elderly women. © 2013 Japan Geriatrics Society.

Population dose commitments due to radioactive releases from nuclear power plant sites in 1988

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

Baker, D.A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1988. Fifty-year commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 71 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km aroundmore » each site receiving various average dose commitments from the airborne pathways. The total collective dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 16 person-rem to a low of 0.0011 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 1.1 person-rem. The total population dose for all sites was estimated at 75 person-rem for the 150 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 3 {times} 10{sup {minus}7} mrem to a high of 0.02 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. However, licensee calculation of doses to the maximally exposed individual at some sites indicated values of up to approximately 100 times average individual doses (on the order of a few millirem per year).« less

Population dose commitments due to radioactive releases from nuclear power plant sites in 1988. Volume 10

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

Baker, D.A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1988. Fifty-year commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 71 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km aroundmore » each site receiving various average dose commitments from the airborne pathways. The total collective dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 16 person-rem to a low of 0.0011 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 1.1 person-rem. The total population dose for all sites was estimated at 75 person-rem for the 150 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 3 {times} 10{sup {minus}7} mrem to a high of 0.02 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. However, licensee calculation of doses to the maximally exposed individual at some sites indicated values of up to approximately 100 times average individual doses (on the order of a few millirem per year).« less

The effect of caffeine as an ergogenic aid in anaerobic exercise.

PubMed

Woolf, Kathleen; Bidwell, Wendy K; Carlson, Amanda G

2008-08-01

The study examined caffeine (5 mg/kg body weight) vs. placebo during anaerobic exercise. Eighteen male athletes (24.1+/-5.8 yr; BMI 26.4+/-2.2 kg/m2) completed a leg press, chest press, and Wingate test. During the caffeine trial, more total weight was lifted with the chest press, and a greater peak power was obtained during the Wingate test. No differences were observed between treatments for the leg press and average power, minimum power, and power drop (Wingate test). There was a significant treatment main effect found for postexercise glucose and insulin concentrations; higher concentrations were found in the caffeine trial. A significant interaction effect (treatment and time) was found for cortisol and glucose concentrations; both increased with caffeine and decreased with placebo. Postexercise systolic blood pressure was significantly higher during the caffeine trial. No differences were found between treatments for serum free-fatty-acid concentrations, plasma lactate concentrations, serum cortisol concentrations, heart rate, and rating of perceived exertion. Thus, a moderate dose of caffeine resulted in more total weight lifted for the chest press and a greater peak power attained during the Wingate test in competitive athletes.

Stochastic ontogenetic growth model

NASA Astrophysics Data System (ADS)

West, B. J.; West, D.

2012-02-01

An ontogenetic growth model (OGM) for a thermodynamically closed system is generalized to satisfy both the first and second law of thermodynamics. The hypothesized stochastic ontogenetic growth model (SOGM) is shown to entail the interspecies allometry relation by explicitly averaging the basal metabolic rate and the total body mass over the steady-state probability density for the total body mass (TBM). This is the first derivation of the interspecies metabolic allometric relation from a dynamical model and the asymptotic steady-state distribution of the TBM is fit to data and shown to be inverse power law.

Modelling energy production by small hydro power plants in collective irrigation networks of Calabria (Southern Italy)

NASA Astrophysics Data System (ADS)

Zema, Demetrio Antonio; Nicotra, Angelo; Tamburino, Vincenzo; Marcello Zimbone, Santo

2017-04-01

The availability of geodetic heads and considerable water flows in collective irrigation networks suggests the possibility of recovery potential energy using small hydro power plants (SHPP) at sustainable costs. This is the case of many Water Users Associations (WUA) in Calabria (Southern Italy), where it could theoretically be possible to recovery electrical energy out of the irrigation season. However, very few Calabrian WUAs have currently built SHPP in their irrigation networks and thus in this region the potential energy is practically fully lost. A previous study (Zema et al., 2016) proposed an original and simple model to site turbines and size their power output as well as to evaluate profits of SHPP in collective irrigation networks. Applying this model at regional scale, this paper estimates the theoretical energy production and the economic performances of SHPP installed in collective irrigation networks of Calabrian WUAs. In more detail, based on digital terrain models processed by GIS and few parameters of the water networks, for each SHPP the model provides: (i) the electrical power output; (iii) the optimal water discharge; (ii) costs, revenues and profits. Moreover, the map of the theoretical energy production by SHPP in collective irrigation networks of Calabria was drawn. The total network length of the 103 water networks surveyed is equal to 414 km and the total geodetic head is 3157 m, of which 63% is lost due to hydraulic losses. Thus, a total power output of 19.4 MW could theoretically be installed. This would provide an annual energy production of 103 GWh, considering SHPPs in operation only out of the irrigation season. The single irrigation networks have a power output in the range 0.7 kW - 6.4 MW. However, the lowest SHPPs (that is, turbines with power output under 5 kW) have been neglected, because the annual profit is very low (on average less than 6%, Zema et al., 2016). On average each irrigation network provides an annual revenue from electrical energy sale of about 103000 €. Even though this revenue may appear quite low, it represents an important share of the annual WUA income. For the entire region, the total revenues from recovery energy in collective irrigation networks through SHPPs have been estimated in about 12 million Euros; investment and operating costs have been evaluated by parametric equations and the total profit theoretically available for each WUA has been quantified. This study has shown the economic opportunity of integrating SHPP in existing collecting irrigation networks of WUAs, in view of providing additional economic resources for users and enhancing the exploitation of a renewable energy source. REFERENCE Zema D.A., Nicotra A., Tamburino V., Zimbone S.M. 2016. A simple method to evaluate the technical and economic feasibility of micro hydro power plants in existing irrigation systems. Renewable Energy 85, 498-506. DOI: 10.1016/j.renene.2015.06.066.

Particulate sulphate and ozone in rural air: Preliminary results from three sites in central England

NASA Astrophysics Data System (ADS)

Martin, A.; Barber, F. R.

Daily particulate sulphate concentrations in air have been measured at a 'background' rural site and at two other sites near rural power stations. The samples were collected by drawing air through filter papers and were analysed by X-ray fluorescence. At the background site the concentration of particulate sulphates was strongly dependent on the O 3 and total S in air. Above a certain 'critical' level of daily O 3, 28% of the daily S in air was particulate on average, but the amounts were not related to the actual O 3 levels. At lower O 3 levels, there appeared to be a constant background of about 2 μg of particulate sulphate per cubic meter of air, together with about 5% of the total S in air as particulate. When black smoke in air was low, the particulate sulphate was also low, despite the O 3 levels. Near the power stations, there was no significantly different rate of production or loss of particulate sulphate. On average, at all three sites over the year, about 12% of the daily total S was particulate, probably corresponding to an average conversion rate of SO 2 of less than 1% per hour. Estimates of hourly particulate sulphates are available from previous measurements at the background site, using a different analysis technique. Particulate sulphate was not found every hour, but typically during 20 h a day in early summer and 8 h a day in early winter. An influence of humidity as well as O 3 was apparent in the peak hourly particulate sulphate values, which reached 60% of the total S. No correlation could be found of particulate sulphate with solar radiation, wind direction, concentrations of oxides of nitrogen in air or ammonium or sulphate in rainwater, but further measurements are planned.

Advanced combined iodine dispenser and detector. [for microorganism annihilation in potable water

NASA Technical Reports Server (NTRS)

Lantz, J. B.; Schubert, F. H.; Jensen, F. C.; Powell, J. D.

1977-01-01

A total weight of 1.23 kg (2.7 lb), a total volume of 1213 cu m (74 cu in), and an average power consumption of 5.5W was achieved in the advanced combined iodine dispenser/detector by integrating the detector with the iodine source, arranging all iodinator components within a compact package and lowering the parasitic power to the detector and electronics circuits. These achievements surpassed the design goals of 1.36 kg (3.0 lb), 1671 cu m (102 cu in) and 8W. The reliability and maintainability were improved by reducing the detector lamp power, using an interchangeable lamp concept, making the electronic circuit boards easily accessible, providing redundant water seals and improving the accessibility to the iodine accumulator for refilling. The system was designed to iodinate (to 5 ppm iodine) the fuel cell water generated during 27 seven-day orbiter missions (equivalent to 18,500 kg (40,700 lb) of water) before the unit must be recharged with iodine crystals.

Bianchi Type-II String Cosmological Model with Magnetic Field in f ( R, T) Gravity

NASA Astrophysics Data System (ADS)

Sharma, N. K.; Singh, J. K.

2014-09-01

The spatially homogeneous and totally anisotropic Bianchi type-II cosmological solutions of massive strings have been investigated in the presence of the magnetic field in the framework of f( R, T) gravity proposed by Harko et al. (Phys Rev D 84:024020, 2011). With the help of special law of variation for Hubble's parameter proposed by Berman (Nuovo Cimento B 74:182, 1983) cosmological model is obtained in this theory. We consider f( R, T) model and investigate the modification R+ f( T) in Bianchi type-II cosmology with an appropriate choice of a function f( T)= μ T. We use the power law relation between average Hubble parameter H and average scale factor R to find the solution. The assumption of constant deceleration parameter leads to two models of universe, i.e. power law model and exponential model. Some physical and kinematical properties of the model are also discussed.

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

Lentine, Anthony L.; Cox, Jonathan Albert

Methods and systems for stabilizing a resonant modulator include receiving pre-modulation and post-modulation portions of a carrier signal, determining the average power from these portions, comparing an average input power to the average output power, and operating a heater coupled to the modulator based on the comparison. One system includes a pair of input structures, one or more processing elements, a comparator, and a control element. The input structures are configured to extract pre-modulation and post-modulation portions of a carrier signal. The processing elements are configured to determine average powers from the extracted portions. The comparator is configured to comparemore » the average input power and the average output power. The control element operates a heater coupled to the modulator based on the comparison.« less

Impacts of lung and tumor volumes on lung dosimetry for nonsmall cell lung cancer.

PubMed

Lei, Weijie; Jia, Jing; Cao, Ruifen; Song, Jing; Hu, Liqin

2017-09-01

The purpose of this study was to determine the impacts of lung and tumor volumes on normal lung dosimetry in three-dimensional conformal radiotherapy (3DCRT), step-and-shoot intensity-modulated radiotherapy (ssIMRT), and single full-arc volumetric-modulated arc therapy (VMAT) in treatment of nonsmall cell lung cancers (NSCLC). All plans were designed to deliver a total dose of 66 Gy in 33 fractions to PTV for the 32 NSCLC patients with various total (bilateral) lung volumes, planning target volumes (PTVs), and PTV locations. The ratio of the lung volume (total lung volume excluding the PTV volume) to the PTV volume (LTR) was evaluated to represent the impacts in three steps. (a) The least squares method was used to fit mean lung doses (MLDs) to PTVs or LTRs with power-law function in the population cohort (N = 32). (b) The population cohort was divided into three groups by LTRs based on first step and then by PTVs, respectively. The MLDs were compared among the three techniques in each LTR group (LG) and each PTV group (PG). (c) The power-law correlation was tested by using the adaptive radiation therapy (ART) planning data of individual patients in the individual cohort (N = 4). Different curves of power-law function with high R 2 values were observed between averaged LTRs and averaged MLDs for 3DCRT, ssIMRT, and VMAT, respectively. In the individual cohort, high R 2 values of fitting curves were also observed in individual patients in ART, although the trend was highly patient-specific. There was a more obvious correlation between LTR and MLD than that between PTV and MLD. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Measurement of Fine Particles From Mobile and Stationary Sources, and Reducing the Air Conditioner Power Consumption in Hybrid Electric Vehicles

NASA Astrophysics Data System (ADS)

Brewer, Eli Henry

We study the PM2.5and ultrafine exhaust emissions from a new natural gas-fired turbine power facility to better understand air pollution in California. To characterize the emissions from new natural gas turbines, a series of tests were performed on a GE LMS100 gas turbine. These tests included PM2.5 and wet chemical tests for SO2/SO 3 and NH3, as well as ultrafine (less than 100 nm in diameter) particulate matter measurements. The turbine exhaust had an average particle number concentration that was 2.3x103 times higher than ambient air. The majority of these particles were nanoparticles; at the 100 nm size, stack particle concentrations were about 20 times higher than ambient, and increased to 3.9x104 times higher on average in the 2.5 - 3 nm particle size range. This study also found that ammonia emissions were higher than expected, but in compliance with permit conditions. This was possibly due to an ammonia imbalance entering the catalyst, some flue gas bypassing the catalyst, or not enough catalyst volume. SO3 accounted for an average of 23% of the total sulfur oxides emissions measured. Some of the SO3 is formed in the combustion process, it is likely that the majority formed as the SO2 in the combustion products passed across the oxidizing CO catalyst and SCR catalyst. The 100 MW turbine sampled in this study emitted particle loadings similar to those previously measured from turbines in the SCAQMD area, however, the turbine exhaust contained far more particles than ambient air. The power consumed by an air conditioner accounts for a significant fraction of the total power used by hybrid and electric vehicles especially during summer. This study examined the effect of recirculation of cabin air on power consumption of mobile air conditioners both in-lab and on-road. Real time power consumption and vehicle mileage were recorded by an On Board Diagnostic monitor and carbon balance method. Vehicle mileage improved with increased cabin air recirculation. The recirculation of cabin air also significantly reduced in-cabin particle concentrations. Recirculation of cabin air is an excellent and immediate solution to increase vehicle mileage and improve cabin air quality.

Active Vibration Control for Helicopter Interior Noise Reduction Using Power Minimization

NASA Technical Reports Server (NTRS)

Mendoza, J.; Chevva, K.; Sun, F.; Blanc, A.; Kim, S. B.

2014-01-01

This report describes work performed by United Technologies Research Center (UTRC) for NASA Langley Research Center (LaRC) under Contract NNL11AA06C. The objective of this program is to develop technology to reduce helicopter interior noise resulting from multiple gear meshing frequencies. A novel active vibration control approach called Minimum Actuation Power (MAP) is developed. MAP is an optimal control strategy that minimizes the total input power into a structure by monitoring and varying the input power of controlling sources. MAP control was implemented without explicit knowledge of the phasing and magnitude of the excitation sources by driving the real part of the input power from the controlling sources to zero. It is shown that this occurs when the total mechanical input power from the excitation and controlling sources is a minimum. MAP theory is developed for multiple excitation sources with arbitrary relative phasing for single or multiple discrete frequencies and controlled by a single or multiple controlling sources. Simulations and experimental results demonstrate the feasibility of MAP for structural vibration reduction of a realistic rotorcraft interior structure. MAP control resulted in significant average global vibration reduction of a single frequency and multiple frequency excitations with one controlling actuator. Simulations also demonstrate the potential effectiveness of the observed vibration reductions on interior radiated noise.

Estimated use of water in the United States in 1990

USGS Publications Warehouse

Solley, Wayne B.; Pierce, Robert R.; Perlman, Howard A.

1993-01-01

Water withdrawals in the United States during 1990 were estimated to average 408,000 million gallons per day (Mgal/d) of freshwater and saline water for offstream uses--2 percent more than the 1985 estimate. Total freshwater withdrawals were an estimated 339,000 Mgal/d during 1990, about the same as during 1985. Average per-capita use for all offstream uses was 1,620 gallons per day (gal/d) of freshwater and saline water combined and 1,340 gal/d of freshwater.Offstream water-use categories are classified in this report as public supply, domestic, commercial, irrigation, livestock, industrial, mining, and thermoelectric power. During 1990, public-supply withdrawals were an estimated 38,500 Mgal/d, and self-supplied withdrawals were estimated as follows: domestic, 3,390 Mgal/d; commercial, 2,390 Mgal/d; irrigation, 137,000 Mgal/d; livestock, 4,500 Mgal/d; industrial, 22,600 Mgal/d, of which 3,270 Mgal/d was saline water; mining, 4,960 Mgal/d, of which 1,650 Mgal/d was saline; and thermoelectric power, 195,000 Mgal/d, of which 64,500 Mgal/d was saline.Water use for hydroelectric power generation, the only instream use compiled in this report, was estimated to be 3,290,000 Mgal/d during 1990, or 8 percent more than during 1985 and about the same as estimated for 1975 and 1980.Estimates of withdrawals by source indicate that during 1990, total surface-water withdrawals were 327,000 Mgal/d, or 1 percent more than during 1985, and total ground-water withdrawals were 80,600 Mgal/d, or 9 percent more than during 1985. Total saline-water withdrawals during 1990 were 69,400 Mgal/d, or 15 percent more than during 1985, most of which was saline surface water. Reclaimed wastewater averaged about 750 Mgal/d during 1990, or 30 percent more than during 1985.Total freshwater consumptive use was an estimated 94,000 Mgal/d during 1990, or 2 percent more than during 1985. Consumptive use by irrigation accounted for the largest part of total consumptive use, and was an estimated 76,200 Mgal/d. Freshwater consumptive use in the East (water-resources regions east of and including the Mississippi regions) was about 12 percent of freshwater withdrawn in the East and accounted for only 21 percent of the Nation's total consumptive use. By comparison, freshwater consumptive use in the West was about 44 percent of the freshwater withdrawn in the West.The 1990 estimates of total freshwater withdrawals and consumptive use were just slightly more than the 1985 estimates but substantially less than the 1980 estimates; this is consistent with the general trend indicated by a slackening in the rate of increase of total withdrawals from 1970 to 1975 and again from 1975 to 1980, and a decrease in total withdrawals from 1980 to 1985. Public-supply withdrawals during 1990 were 5 percent more than during 1985, and self-supplied withdrawals during 1990 compared to 1985 were as follows: domestic, 2 percent more; commercial, 95 percent more; irrigation, 0.3 percent less; livestock, 0.8 percent more; industrial, 13 percent less; mining, 44 percent more; and thermoelectric power, 4 percent more.A comparison of total withdrawals (fresh, saline) by State indicates that 20 States and the District of Columbia had less water withdrawn for offstream uses during 1990 than during 1985. California accounted for the most water withdrawn for offstream use, 46,800 Mgal/d, more than the total of water withdrawn in both Texas or Idaho, the next largest users. A similar comparison by water-resources regions indicates that the coastal regions (New England, Mid Atlantic, South Atlantic-Gulf, Pacific Northwest, California) accounted for nearly one-half of the total water withdrawn in the United States. Total withdrawals in the East accounted for 54 percent of the Nation's total withdrawals, the same as during 1985.

Develop and test fuel cell powered on site integrated total energy systems. Phase 3: Full-scale power plant development

NASA Technical Reports Server (NTRS)

Kaufman, A.; Olson, B.; Pudick, S.; Wang, C. L.; Werth, J.; Whelan, J. A.

1986-01-01

The third in a series of 4kW stacks, consisting of 24 cells of the 13 inch x 23 inch cell size, has been on test for about 1600 hours. This stack is similar to the first two stacks, which ran 7000 and 8400 hours, respectively. The present stack incorporates technology improvements relating to the electrolyte-matrix, the current-collector assembly, and a reduction in the number of cooling plates. Performance is currently averaging about 0.64 per cell at 161 mA sq cm.

Design, experimental analysis, and unsteady Reynolds-averaged Navier-Stokes simulation of laboratory-scale counter-rotating vertical-axis turbines in marine environment

NASA Astrophysics Data System (ADS)

Doan, Minh; Padricelli, Claudrio; Obi, Shinnosuke; Totsuka, Yoshitaka

2017-11-01

We present the torque and power measurement of laboratory-scale counter-rotating vertical-axis hydrokinetic turbines, built around a magnetic hysteresis brake as the speed controller and a Hall-effect sensor as the rotational speed transducer. A couple of straight-three-bladed turbines were linked through a transmission of spur gears and timing pulleys and coupled to the electronic instrumentation via flexible shaft couplers. A total of 8 experiments in 2 configurations were conducted in the water channel facility (4-m long, 0.3-m wide, and 0.15-m deep). Power generation of the turbines (0.06-m rotor diameter) was measured and compared with that of single turbines of the same size. The wakes generated by these experiments were also measured by particle image velocimetry (PIV) and numerically simulated by unsteady Reynolds-averaged Navier-Stokes (URANS) simulation using OpenFOAM. Preliminary results from wake measurement indicated the mechanism of enhanced power production behind the counter-rotating configuration of vertical-axis turbines. Current address: Politecnico di Milano.

Effects of sea state on offshore wind resourcing in Florida

NASA Astrophysics Data System (ADS)

Collier, Cristina

Offshore resource assessment relies on estimating wind speeds at turbine hub height using observations typically made at substantially lower height. The methods used to adjust from observed wind speeds to hub height can impact resource estimation. The importance of directional sea state is examined, both as seasonal averages and as a function of the diurnal cycle. A General Electric 3.6 MW offshore turbine is used as a model for a power production. Including sea state increases or decreases seasonally averaged power production by roughly 1%, which is found to be an economically significant change. These changes occur because the sea state modifies the wind shear (vector wind difference between the buoy height and the moving surface) and therefore the extrapolation from the observation to hub height is affected. These seemingly small differences in capacity can alter profits by millions of dollars depending upon the size of the farm and fluctuations in price per kWh throughout the year. A 2% change in capacity factor can lead to a 10 million dollar difference from total kWh produced from a wind farm of 100 3.6MW turbines. These economic impacts can be a deciding factor in determining whether a resource is viable for development. Modification of power output due to sea states are shown for seasonal and diurnal time scales. Three regions are examined herein: West Florida, East Florida, and Nantucket Sound. The average capacity after sea state is included suggests areas around Florida could provide substantial amounts of wind power throughout three-fourths of the calendar year. At certain times of day winter average produced capacity factors in West Florida can be up to 45% more than in summer when sea state is included. Nantucket Sound capacity factors are calculated for comparison to a region near a planned United States offshore wind farm. This study provides evidence to suggest including sea state in offshore wind resource assessment causes economically significant differences for offshore wind power siting.

Influence of Posterior Corneal Astigmatism on Total Corneal Astigmatism in Eyes With Keratoconus.

PubMed

Savini, Giacomo; Næser, Kristian; Schiano-Lomoriello, Domenico; Mularoni, Alessandro

2016-11-01

To measure posterior corneal astigmatism (PCA) and investigate its influence on total corneal astigmatism (TCA) in eyes with keratoconus. Keratometric astigmatism (KA), PCA, and TCA were investigated by means of a dual Scheimpflug analyzer in patients with keratoconus. Vector analysis was carried out with the Næser polar value method. We enrolled 119 eyes. PCA magnitude averaged 0.77 ± 0.43 diopters (D) and exceeded 0.50, 1.00, and 2.00 D in 73.9%, 21.8%, and 16.8% of eyes, respectively. PCA averaged 0.95 ± 0.48, 0.55 ± 0.28, and 0.70 ± 0.35 D in eyes with with-the-rule (WTR), against-the-rule (ATR), and oblique astigmatism. The steepest posterior meridian was oriented vertically (between 61 and 119 degrees) in 55.5% of eyes, thus generating ATR astigmatism. The difference between the location of the steepest meridian of KA and that of TCA was >10 degrees in 8.4% of eyes. On average, KA overestimated TCA in eyes with WTR astigmatism by 0.16 D and underestimated TCA in eyes with ATR astigmatism by 0.22 D. The PCA power oriented along the steeper anterior corneal meridian averaged -0.83 ± 0.40, -0.40 ± 0.37, and -0.53 ± 0.43 D for WTR, ATR, and obliquely astigmatic eyes, respectively. Linear regression disclosed a statistically significant correlation (P < 0.0001, r = 0.16) between the meridional powers of TCA and PCA. In eyes with keratoconus, PCA displays large, variable values and is correlated to TCA. The influence of PCA on TCA cannot be disregarded when planning astigmatism correction by toric intraocular lenses.

Multi-Watt Average Power Nanosecond Microchip Laser and Power Scalability Estimates

NASA Technical Reports Server (NTRS)

Konoplev, Oleg A.; Vasilyev, Alexey A.; Seas, Antonios A.; Yu, Anthony W.; Li, Steven X.; Shaw, George B.; Stephen, Mark A.; Krainak, Michael A.

2011-01-01

We demonstrated up to 2 W average power, CW-pumped, passively- Q-switched, 1.5 ns monolithic MCL with single-longitudinal mode-operation. We discuss laser design issues to bring the average power to 5-1 OW and beyond.

Magnetic properties of X-ray bright points. [in sun

NASA Technical Reports Server (NTRS)

Golub, L.; Krieger, A. S.; Harvey, J. W.; Vaiana, G. S.

1977-01-01

Using high-resolution Kitt Peak National Observatory magnetograms and sequences of simultaneous S-054 soft X-ray solar images, the properties of X-ray bright points (XBP) and ephemeral active regions (ER) are compared. All XBP appear on the magnetograms as bipolar features, except for very recently emerged or old and decayed XBP. The separation of the magnetic bipoles is found to increase with the age of the XBP, with an average emergence growth rate of 2.2 plus or minus 0.4 km per sec. The total magnetic flux in a typical XBP living about 8 hr is found to be about two times ten to the nineteenth power Mx. A proportionality is found between XBP lifetime and total magnetic flux, equivalent to about ten to the twentieth power Mx per day of lifetime.

Using Reanalysis Data for the Prediction of Seasonal Wind Turbine Power Losses Due to Icing

NASA Astrophysics Data System (ADS)

Burtch, D.; Mullendore, G. L.; Delene, D. J.; Storm, B.

2013-12-01

The Northern Plains region of the United States is home to a significant amount of potential wind energy. However, in winter months capturing this potential power is severely impacted by the meteorological conditions, in the form of icing. Predicting the expected loss in power production due to icing is a valuable parameter that can be used in wind turbine operations, determination of wind turbine site locations and long-term energy estimates which are used for financing purposes. Currently, losses due to icing must be estimated when developing predictions for turbine feasibility and financing studies, while icing maps, a tool commonly used in Europe, are lacking in the United States. This study uses the Modern-Era Retrospective Analysis for Research and Applications (MERRA) dataset in conjunction with turbine production data to investigate various methods of predicting seasonal losses (October-March) due to icing at two wind turbine sites located 121 km apart in North Dakota. The prediction of icing losses is based on temperature and relative humidity thresholds and is accomplished using three methods. For each of the three methods, the required atmospheric variables are determined in one of two ways: using industry-specific software to correlate anemometer data in conjunction with the MERRA dataset and using only the MERRA dataset for all variables. For each season, a percentage of the total expected generated power lost due to icing is determined and compared to observed losses from the production data. An optimization is performed in order to determine the relative humidity threshold that minimizes the difference between the predicted and observed values. Eight seasons of data are used to determine an optimal relative humidity threshold, and a further three seasons of data are used to test this threshold. Preliminary results have shown that the optimized relative humidity threshold for the northern turbine is higher than the southern turbine for all methods. For the three test seasons, the optimized thresholds tend to under-predict the icing losses. However, the threshold determined using boundary layer similarity theory most closely predicts the power losses due to icing versus the other methods. For the northern turbine, the average predicted power loss over the three seasons is 4.65 % while the observed power loss is 6.22 % (average difference of 1.57 %). For the southern turbine, the average predicted power loss and observed power loss over the same time period are 4.43 % and 6.16 %, respectively (average difference of 1.73 %). The three-year average, however, does not clearly capture the variability that exists season-to-season. On examination of each of the test seasons individually, the optimized relative humidity threshold methodology performs better than fixed power loss estimates commonly used in the wind energy industry.

The countermovement jump to monitor neuromuscular status: A meta-analysis.

PubMed

Claudino, João Gustavo; Cronin, John; Mezêncio, Bruno; McMaster, Daniel Travis; McGuigan, Michael; Tricoli, Valmor; Amadio, Alberto Carlos; Serrão, Julio Cerca

2017-04-01

The primary objective of this meta-analysis was to compare countermovement jump (CMJ) performance in studies that reported the highest value as opposed to average value for the purposes of monitoring neuromuscular status (i.e., fatigue and supercompensation). The secondary aim was to determine the sensitivity of the dependent variables. Systematic review with meta-analysis. The meta-analysis was conducted on the highest or average of a number of CMJ variables. Multiple literature searches were undertaken in Pubmed, Scopus, and Web of Science to identify articles utilizing CMJ to monitor training status. Effect sizes (ES) with 95% confidence interval (95% CI) were calculated using the mean and standard deviation of the pre- and post-testing data. The coefficient of variation (CV) with 95% CI was also calculated to assess the level of instability of each variable. Heterogeneity was assessed using a random-effects model. 151 articles were included providing a total of 531 ESs for the meta-analyses; 85.4% of articles used highest CMJ height, 13.2% used average and 1.3% used both when reporting changes in CMJ performance. Based on the meta-analysis, average CMJ height was more sensitive than highest CMJ height in detecting CMJ fatigue and supercompensation. Furthermore, other CMJ variables such as peak power, mean power, peak velocity, peak force, mean impulse, and power were sensitive in tracking the supercompensation effects of training. The average CMJ height was more sensitive than highest CMJ height in monitoring neuromuscular status; however, further investigation is needed to determine the sensitivity of other CMJ performance variables. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

An experimental aluminum-fueled power plant

NASA Astrophysics Data System (ADS)

Vlaskin, M. S.; Shkolnikov, E. I.; Bersh, A. V.; Zhuk, A. Z.; Lisicyn, A. V.; Sorokovikov, A. I.; Pankina, Yu. V.

2011-10-01

An experimental co-generation power plant (CGPP-10) using aluminum micron powder (with average particle size up to 70 μm) as primary fuel and water as primary oxidant was developed and tested. Power plant can work in autonomous (unconnected from industrial network) nonstop regime producing hydrogen, electrical energy and heat. One of the key components of experimental plant is aluminum-water high-pressure reactor projected for hydrogen production rate of ∼10 nm3 h-1. Hydrogen from the reactor goes through condenser and dehumidifier and with -25 °C dew-point temperature enters into the air-hydrogen fuel cell 16 kW-battery. From 1 kg of aluminum the experimental plant produces 1 kWh of electrical energy and 5-7 kWh of heat. Power consumer gets about 10 kW of electrical power. Plant electrical and total efficiencies are 12% and 72%, respectively.

Life Cycle Assessment of Coal-fired Power Production

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

Spath, P. L.; Mann, M. K.; Kerr, D. R.

1999-09-01

Coal has the largest share of utility power generation in the US, accounting for approximately 56% of all utility-produced electricity (US DOE, 1998). Therefore, understanding the environmental implications of producing electricity from coal is an important component of any plan to reduce total emissions and resource consumption. A life cycle assessment (LCA) on the production of electricity from coal was performed in order to examine the environmental aspects of current and future pulverized coal boiler systems. Three systems were examined: (1) a plant that represents the average emissions and efficiency of currently operating coal-fired power plants in the US (thismore » tells us about the status quo), (2) a new coal-fired power plant that meets the New Source Performance Standards (NSPS), and (3) a highly advanced coal-fired power plant utilizing a low emission boiler system (LEBS).« less

Generation of 180 W average green power from a frequency-doubled picosecond rod fiber amplifier

DOE PAGES

Zhao, Zhi; Sheehy, Brian; Minty, Michiko

2017-03-29

Here, we report on the generation of 180 W average green power from a frequency-doubled picosecond rod fiber amplifier. In an Yb-doped fiber master-oscillator-power-amplifier system, 2.3-ps 704 MHz pulses are first amplified in small-core fibers and then in large-mode-area rod fibers to produce 270 W average infrared power with a high polarization extinction ratio and diffraction-limited beam quality. By carrying out frequency doubling in a lithium triborate (LBO) crystal, 180 W average green power is generated. To the best of our knowledge, this is the highest average green power achieved in fiber-based laser systems.

Contribution of the crystalline lens gradient refractive index to the accommodation amplitude in non-human primates: In vitro studies

PubMed Central

Maceo, Bianca M.; Manns, Fabrice; Borja, David; Nankivil, Derek; Uhlhorn, Stephen; Arrieta, Esdras; Ho, Arthur; Augusteyn, Robert C.; Parel, Jean-Marie

2012-01-01

The purpose of this study was to determine the contribution of the gradient refractive index to the change in lens power in hamadryas baboon and cynomolgus monkey lenses during simulated accommodation in a lens stretcher. Thirty-six monkey lenses (1.4–14.1 years) and twenty-five baboon lenses (1.8–28.0 years) were stretched in discrete steps. At each stretching step, the lens back vertex power was measured and the lens cross-section was imaged with optical coherence tomography. The radii of curvature for the lens anterior and posterior surfaces were calculated for each step. The power of each lens surface was determined using refractive indices of 1.365 for the outer cortex and 1.336 for the aqueous. The gradient contribution was calculated by subtracting the power of the surfaces from the measured lens power. In all lenses, the contribution of the surfaces and gradient increased linearly with the amplitude of accommodation. The gradient contributes on average 65 ± 3% for monkeys and 66 ± 3% for baboons to the total power change during accommodation. When expressed in percent of the total power change, the relative contribution of the gradient remains constant with accommodation and age in both species. These findings are consistent with Gullstrand’s intracapsular theory of accommodation. PMID:22131444

Active cooling of pulse compression diffraction gratings for high energy, high average power ultrafast lasers

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

Alessi, David A.; Rosso, Paul A.; Nguyen, Hoang T.

Laser energy absorption and subsequent heat removal from diffraction gratings in chirped pulse compressors poses a significant challenge in high repetition rate, high peak power laser development. In order to understand the average power limitations, we have modeled the time-resolved thermo-mechanical properties of current and advanced diffraction gratings. We have also developed and demonstrated a technique of actively cooling Petawatt scale, gold compressor gratings to operate at 600W of average power - a 15x increase over the highest average power petawatt laser currently in operation. As a result, combining this technique with low absorption multilayer dielectric gratings developed in ourmore » group would enable pulse compressors for petawatt peak power lasers operating at average powers well above 40kW.« less

Active cooling of pulse compression diffraction gratings for high energy, high average power ultrafast lasers

DOE PAGES

Alessi, David A.; Rosso, Paul A.; Nguyen, Hoang T.; ...

2016-12-26

Laser energy absorption and subsequent heat removal from diffraction gratings in chirped pulse compressors poses a significant challenge in high repetition rate, high peak power laser development. In order to understand the average power limitations, we have modeled the time-resolved thermo-mechanical properties of current and advanced diffraction gratings. We have also developed and demonstrated a technique of actively cooling Petawatt scale, gold compressor gratings to operate at 600W of average power - a 15x increase over the highest average power petawatt laser currently in operation. As a result, combining this technique with low absorption multilayer dielectric gratings developed in ourmore » group would enable pulse compressors for petawatt peak power lasers operating at average powers well above 40kW.« less

Generalized radiation-field quantization method and the Petermann excess-noise factor

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

Cheng, Y.-J.; Siegman, A.E.; E.L. Ginzton Laboratory, Stanford University, Stanford, California 94305

2003-10-01

We propose a generalized radiation-field quantization formalism, where quantization does not have to be referenced to a set of power-orthogonal eigenmodes as conventionally required. This formalism can be used to directly quantize the true system eigenmodes, which can be non-power-orthogonal due to the open nature of the system or the gain/loss medium involved in the system. We apply this generalized field quantization to the laser linewidth problem, in particular, lasers with non-power-orthogonal oscillation modes, and derive the excess-noise factor in a fully quantum-mechanical framework. We also show that, despite the excess-noise factor for oscillating modes, the total spatially averaged decaymore » rate for the laser atoms remains unchanged.« less

Mathematical optimization techniques for managing selective catalytic reduction for a fleet of coal-fired power plants

NASA Astrophysics Data System (ADS)

Alanis Pena, Antonio Alejandro

Major commercial electricity generation is done by burning fossil fuels out of which coal-fired power plants produce a substantial quantity of electricity worldwide. The United States has large reserves of coal, and it is cheaply available, making it a good choice for the generation of electricity on a large scale. However, one major problem associated with using coal for combustion is that it produces a group of pollutants known as nitrogen oxides (NO x). NOx are strong oxidizers and contribute to ozone formation and respiratory illness. The Environmental Protection Agency (EPA) regulates the quantity of NOx emitted to the atmosphere in the United States. One technique coal-fired power plants use to reduce NOx emissions is Selective Catalytic Reduction (SCR). SCR uses layers of catalyst that need to be added or changed to maintain the required performance. Power plants do add or change catalyst layers during temporary shutdowns, but it is expensive. However, many companies do not have only one power plant, but instead they can have a fleet of coal-fired power plants. A fleet of power plants can use EPA cap and trade programs to have an outlet NOx emission below the allowances for the fleet. For that reason, the main aim of this research is to develop an SCR management mathematical optimization methods that, with a given set of scheduled outages for a fleet of power plants, minimizes the total cost of the entire fleet of power plants and also maintain outlet NO x below the desired target for the entire fleet. We use a multi commodity network flow problem (MCFP) that creates edges that represent all the SCR catalyst layers for each plant. This MCFP is relaxed because it does not consider average daily NOx constraint, and it is solved by a binary integer program. After that, we add the average daily NOx constraint to the model with a schedule elimination constraint (MCFPwSEC). The MCFPwSEC eliminates, one by one, the solutions that do not satisfy the average daily NOx constraint and the worst NH 3 slip until it finds the solution that satisfies that requirement. We introduce an algorithm called heuristic MCFPwSEC (HMCFPwSEC). When HMCFPwSEC algorithm starts, we calculate the cost of the edges estimating the average NH3 slip level, but after we have a schedule that satisfies the average daily NOx constraint and the worst NH3 slip, we update the cost of the edges with the average NH3 slip for this schedule. We repeat this process until we have the solution. Because HMCFPwSEC does not guarantee optimality, we compare its results with SGO, which is optimal, using computational experiments. The results between both models are very similar, the only important difference is the time to solve each model. Then, a fleet HMCFPwSEC (FHMCFPwSEC) uses HMCFPwSEC to create the SCR management plan for each plant of the fleet, with a discrete NOx emissions value for each plant. FHMCFPwSEC repeats this process with different discrete levels of NOx emissions, for each plant, in order to create a new problem with schedules with different cost and NO x emissions for each plant of the fleet. Finally, FHMCFPwSEC solves this new problem with a binary integer program, in order to satisfy a NO x emission value for the fleet that also minimizes the total cost for the fleet, and using each plant once. FHMCFPwSEC can work with single cut and also with multi-cut methods. Because FHMCFPwSEC does not guarantee optimality, we compare its results with fleet SGO (FSGO) using computational experiments. The results between both models are very similar, the only important difference is the time to solve each model. In the experiments, FHMCFPwSEC multi-cut targeting new layer always uses less time than FSGO.

Effect of the equivalent refractive index on intraocular lens power prediction with ray tracing after myopic laser in situ keratomileusis.

PubMed

Canovas, Carmen; van der Mooren, Marrie; Rosén, Robert; Piers, Patricia A; Wang, Li; Koch, Douglas D; Artal, Pablo

2015-05-01

To determine the impact of the equivalent refractive index (ERI) on intraocular lens (IOL) power prediction for eyes with previous myopic laser in situ keratomileusis (LASIK) using custom ray tracing. AMO B.V., Groningen, the Netherlands, and the Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, USA. Retrospective data analysis. The ERI was calculated individually from the post-LASIK total corneal power. Two methods to account for the posterior corneal surface were tested; that is, calculation from pre-LASIK data or from post-LASIK data only. Four IOL power predictions were generated using a computer-based ray-tracing technique, including individual ERI results from both calculation methods, a mean ERI over the whole population, and the ERI for normal patients. For each patient, IOL power results calculated from the four predictions as well as those obtained with the Haigis-L were compared with the optimum IOL power calculated after cataract surgery. The study evaluated 25 patients. The mean and range of ERI values determined using post-LASIK data were similar to those determined from pre-LASIK data. Introducing individual or an average ERI in the ray-tracing IOL power calculation procedure resulted in mean IOL power errors that were not significantly different from zero. The ray-tracing procedure that includes an average ERI gave a greater percentage of eyes with an IOL power prediction error within ±0.5 diopter than the Haigis-L (84% versus 52%). For IOL power determination in post-LASIK patients, custom ray tracing including a modified ERI was an accurate procedure that exceeded the current standards for normal eyes. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Sensitivity of a phase-sensitive optical time-domain reflectometer with a semiconductor laser source

NASA Astrophysics Data System (ADS)

Alekseev, A. E.; Tezadov, Ya A.; Potapov, V. T.

2018-06-01

In the present paper we perform, for the first time, an analysis of the average sensitivity of a coherent phase-sensitive optical time-domain reflectometer (phase-OTDR) with a semiconductor laser source to external actions. The sensitivity of this OTDR can be defined in a conventional manner via average SNR at its output, which in turn is defined by the average useful signal power and the average intensity noise power in the OTDR spatial channels in the bandwidth defined by the OTDR sampling frequency. The average intensity noise power is considered in detail in a previous paper. In the current paper we examine the average useful signal power at the output of a phase-OTDR. The analysis of the average useful signal power of a phase-OTDR is based on the study of a fiber scattered-light interferometer (FSLI) which is treated as a constituent part of a phase- OTDR. In the analysis, one of the conventional phase-OTDR schemes with a rectangular dual-pulse probe signal is considered. The FSLI which corresponds to this OTDR scheme has two scattering fiber segments with additional time delay, introduced between backscattered fields. The average useful signal power and the resulting average SNR at the output of this FSLI are determined by the degree of coherence of the semiconductor laser source, the length of the scattering fiber segments, and by the additional time delay between the scattering fiber segments. The average useful signal power characteristic of the corresponding phase-OTDR is determined by analogous parameters: the source coherence, the time durations of the parts constituting the dual-pulse, and the time interval which separates these parts. In the paper an expression for the average useful signal power of a phase-OTDR is theoretically derived and experimentally verified. Based on the found average useful signal power of a phase-OTDR and the average intensity noise power, derived in the previous paper, the average SNR of a phase-OTDR is defined. Setting the average signal SNR to 1, at a defined spectral band the minimum detectable external action amplitude for our particular phase-OTDR setup is determined. We also derive a simple relation for the average useful signal power and the average SNR which results when making the assumption that the laser source coherence is high. The results of the paper can serve as the basis for further development of the concept of phase-OTDR sensitivity.

Using Bayes Model Averaging for Wind Power Forecasts

NASA Astrophysics Data System (ADS)

Preede Revheim, Pål; Beyer, Hans Georg

2014-05-01

For operational purposes predictions of the forecasts of the lumped output of groups of wind farms spread over larger geographic areas will often be of interest. A naive approach is to make forecasts for each individual site and sum them up to get the group forecast. It is however well documented that a better choice is to use a model that also takes advantage of spatial smoothing effects. It might however be the case that some sites tends to more accurately reflect the total output of the region, either in general or for certain wind directions. It will then be of interest giving these a greater influence over the group forecast. Bayesian model averaging (BMA) is a statistical post-processing method for producing probabilistic forecasts from ensembles. Raftery et al. [1] show how BMA can be used for statistical post processing of forecast ensembles, producing PDFs of future weather quantities. The BMA predictive PDF of a future weather quantity is a weighted average of the ensemble members' PDFs, where the weights can be interpreted as posterior probabilities and reflect the ensemble members' contribution to overall forecasting skill over a training period. In Revheim and Beyer [2] the BMA procedure used in Sloughter, Gneiting and Raftery [3] were found to produce fairly accurate PDFs for the future mean wind speed of a group of sites from the single sites wind speeds. However, when the procedure was attempted applied to wind power it resulted in either problems with the estimation of the parameters (mainly caused by longer consecutive periods of no power production) or severe underestimation (mainly caused by problems with reflecting the power curve). In this paper the problems that arose when applying BMA to wind power forecasting is met through two strategies. First, the BMA procedure is run with a combination of single site wind speeds and single site wind power production as input. This solves the problem with longer consecutive periods where the input data does not contain information, but it has the disadvantage of nearly doubling the number of model parameters to be estimated. Second, the BMA procedure is run with group mean wind power as the response variable instead of group mean wind speed. This also solves the problem with longer consecutive periods without information in the input data, but it leaves the power curve to also be estimated from the data. [1] Raftery, A. E., et al. (2005). Using Bayesian Model Averaging to Calibrate Forecast Ensembles. Monthly Weather Review, 133, 1155-1174. [2]Revheim, P. P. and H. G. Beyer (2013). Using Bayesian Model Averaging for wind farm group forecasts. EWEA Wind Power Forecasting Technology Workshop,Rotterdam, 4-5 December 2013. [3]Sloughter, J. M., T. Gneiting and A. E. Raftery (2010). Probabilistic Wind Speed Forecasting Using Ensembles and Bayesian Model Averaging. Journal of the American Statistical Association, Vol. 105, No. 489, 25-35

The independent effects of speed and propulsive force on joint power generation in walking.

PubMed

Browne, Michael G; Franz, Jason R

2017-04-11

Walking speed is modulated using propulsive forces (F P ) during push-off and both preferred speed and F P decrease with aging. However, even prior to walking slower, reduced F P may be accompanied by potentially unfavorable changes in joint power generation. For example, compared to young adults, older adults exhibit a redistribution of mechanical power generation from the propulsive plantarflexor muscles to more proximal muscles acting across the knee and hip. Here, we used visual biofeedback based on real-time F P measurements to decouple and investigate the interaction between joint-level coordination, whole-body F P , and walking speed. 12 healthy young subjects walked on a dual-belt instrumented treadmill at a range of speeds (0.9-1.3m/s). We immediately calculated the average F P from each speed. Subjects then walked at 1.3m/s while completing a series of biofeedback trials with instructions to match their instantaneous F P to their averaged F P from slower speeds. Walking slower decreased F P and total positive joint work with little effect on relative joint-level contributions. Conversely, subjects walked at a constant speed with reduced F P , not by reducing total positive joint work, but by redistributing the mechanical demands of each step from the plantarflexor muscles during push-off to more proximal leg muscles during single support. Interestingly, these naturally emergent joint- and limb-level biomechanical changes, in the absence of neuromuscular constraints, resemble those due to aging. Our findings provide important reference data to understand the presumably complex interactions between joint power generation, whole-body F P , and walking speed in our aging population. Copyright © 2017 Elsevier Ltd. All rights reserved.

Time-dependent polar distribution of outgassing from a spacecraft

NASA Technical Reports Server (NTRS)

Scialdone, J. J.

1974-01-01

A technique has been developed to obtain a characterization of the self-generated environment of a spacecraft and its variation with time, angular position, and distance. The density, pressure, outgassing flux, total weight loss, and other important parameters were obtained from data provided by two mass measuring crystal microbalances, mounted back to back, at distance of 1 m from the spacecraft equivalent surface. A major outgassing source existed at an angular position of 300 deg to 340 deg, near the rocket motor, while the weakest source was at the antennas. The strongest source appeared to be caused by a material diffusion process which produced a directional density at 1 m distance of about 1.6 x 10 to the 11th power molecules/cu cm after 1 hr in vacuum and decayed to 1.6 x 10 to the 9th power molecules/cu cm after 200 hr. The total average outgassing flux at the same distance and during the same time span changed from 1.2 x 10 to the minus 7th power to 1.4 x to the minus 10th power g/sq cm/s. These values are three times as large at the spacecraft surface. Total weight loss was 537 g after 10 hr and about 833 g after 200 hr. Self-contamination of the spacecraft was equivalent to that in orbit at about 300-km altitude.

Ultra-low noise miniaturized neural amplifier with hardware averaging.

PubMed

Dweiri, Yazan M; Eggers, Thomas; McCallum, Grant; Durand, Dominique M

2015-08-01

Peripheral nerves carry neural signals that could be used to control hybrid bionic systems. Cuff electrodes provide a robust and stable interface but the recorded signal amplitude is small (<3 μVrms 700 Hz-7 kHz), thereby requiring a baseline noise of less than 1 μVrms for a useful signal-to-noise ratio (SNR). Flat interface nerve electrode (FINE) contacts alone generate thermal noise of at least 0.5 μVrms therefore the amplifier should add as little noise as possible. Since mainstream neural amplifiers have a baseline noise of 2 μVrms or higher, novel designs are required. Here we apply the concept of hardware averaging to nerve recordings obtained with cuff electrodes. An optimization procedure is developed to minimize noise and power simultaneously. The novel design was based on existing neural amplifiers (Intan Technologies, LLC) and is validated with signals obtained from the FINE in chronic dog experiments. We showed that hardware averaging leads to a reduction in the total recording noise by a factor of 1/√N or less depending on the source resistance. Chronic recording of physiological activity with FINE using the presented design showed significant improvement on the recorded baseline noise with at least two parallel operation transconductance amplifiers leading to a 46.1% reduction at N = 8. The functionality of these recordings was quantified by the SNR improvement and shown to be significant for N = 3 or more. The present design was shown to be capable of generating <1.5 μVrms total recording baseline noise when connected to a FINE placed on the sciatic nerve of an awake animal. An algorithm was introduced to find the value of N that can minimize both the power consumption and the noise in order to design a miniaturized ultralow-noise neural amplifier. These results demonstrate the efficacy of hardware averaging on noise improvement for neural recording with cuff electrodes, and can accommodate the presence of high source impedances that are associated with the miniaturized contacts and the high channel count in electrode arrays. This technique can be adopted for other applications where miniaturized and implantable multichannel acquisition systems with ultra-low noise and low power are required.

Pulsed and CW adjustable 1942 nm single-mode all-fiber Tm-doped fiber laser system for surgical laser soft tissue ablation applications.

PubMed

Huang, Yize; Jivraj, Jamil; Zhou, Jiaqi; Ramjist, Joel; Wong, Ronnie; Gu, Xijia; Yang, Victor X D

2016-07-25

A surgical laser soft tissue ablation system based on an adjustable 1942 nm single-mode all-fiber Tm-doped fiber laser operating in pulsed or CW mode with nitrogen assistance is demonstrated. Ex vivo ablation on soft tissue targets such as muscle (chicken breast) and spinal cord (porcine) with intact dura are performed at different ablation conditions to examine the relationship between the system parameters and ablation outcomes. The maximum laser average power is 14.4 W, and its maximum peak power is 133.1 W with 21.3 μJ pulse energy. The maximum CW power density is 2.33 × 10⁶ W/cm² and the maximum pulsed peak power density is 2.16 × 10⁷ W/cm². The system parameters examined include the average laser power in CW or pulsed operation mode, gain-switching frequency, total ablation exposure time, and the input gas flow rate. The ablation effects were measured by microscopy and optical coherence tomography (OCT) to evaluate the ablation depth, superficial heat-affected zone diameter (HAZD) and charring diameter (CD). Our results conclude that the system parameters can be tailored to meet different clinical requirements such as ablation for soft tissue cutting or thermal coagulation for future applications of hemostasis.

Effect of Microwave Radiation Power on the Size of Aggregates of ZnO NPs Prepared Using Microwave Solvothermal Synthesis

PubMed Central

Chudoba, Tadeusz; Gierlotka, Stanisław; Lojkowski, Witold

2018-01-01

This paper reports the possibility of changing the size of zinc oxide nanoparticles (ZnO NPs) aggregates through a change of synthesis parameters. The effect of the changed power of microwave heating on the properties of ZnO NPs obtained by the microwave solvothermal synthesis from zinc acetate dissolved in ethylene glycol was tested for the first time. It was found that the size of ZnO aggregates ranged from 60 to 120 nm depending on the power of microwave radiation used in the synthesis of ZnO NPs. The increase in the microwave radiation power resulted in the reduction of the total synthesis time with simultaneous preservation of the constant size and shape of single ZnO NPs, which were synthesized at a pressure of 4 bar. All the obtained ZnO NPs samples were composed of homogeneous spherical particles that were single crystals with an average size of 27 ± 3 nm with a developed specific surface area of 40 m2/g and the skeleton density of 5.18 ± 0.03 g/cm3. A model of a mechanism explaining the correlation between the size of aggregates and the power of microwaves was proposed. This method of controlling the average size of ZnO NPs aggregates is presented for the first time and similar investigations are not found in the literature. PMID:29783651

Population dose commitments due to radioactive releases from nuclear power plant sites in 1985

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

Baker, D.A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commericial power reactors operating during 1985. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 61 sites. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km aroundmore » each site receiving various average dose commitments from the airborne pathways. The total dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 73 person-rem to a low of 0.011 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 3 person-rem. The total population dose for all sites was estimated at 200 person-rem for the 110 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 5 /times/ 10/sup /minus/6/ mrem to a high of 0.02 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.« less

Population dose commitments due to radioactive releases from nuclear power plant sites in 1984

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

Baker, D.A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1984. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 56 sites. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km aroundmore » each site receiving various average dose commitments from the airborne pathways. The total dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 110 person-rem to a low of 0.002 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 5 person-rem. The total population dose for all sites was estimated at 280 person-rem for the 100 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 6 x 10/sup -6/ mrem to a high of 0.04 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.« less

Population dose commitments due to radioactive releases from nuclear power plant sites in 1986

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

Baker, D.A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1986. Fifty-year dose commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 66 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 kmmore » around each site receiving various average dose commitments from the airborne pathways. The total dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 31 person-rem to a low of 0.0007 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 1.7 person-rem. The total population dose for all sites was estimated at 110 person-rem for the 140 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 2 {times} 10{sup -6} mrem to a high of 0.02 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. 12 refs.« less

Population dose commitments due to radioactive releases from nuclear power plant sites in 1982. Volume 4

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

Baker, D.A.; Peloquin, R.A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1982. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 51 sites. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each sitemore » receiving various average dose commitments from the airborne pathways. The total dose commitments from both liquid and airborne pathways ranged from a high of 30 person-rem to a low of 0.007 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 3 person-rem. The total population dose for all sites was estimated at 130 person-rem for the 100 million people considered at risk. The average individual dose commitment from all pathways on a site basis ranged from a low of 6 x 10/sup -7/ mrem to a high of 0.06 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.« less

Estimated use of water in the Tennessee River watershed in 2000 and projections of water use to 2030

USGS Publications Warehouse

Hutson, Susan S.; Koroa, M. Carolyn; Murphree, C. Michael

2003-01-01

Estimates indicate that after increases in water withdrawals from 1965 to 1980 in the Tennessee River watershed, withdrawals declined from 1980 to 1985 and remained steady from 1985 to 1995. Water withdrawals in the Tennessee River watershed during 2000 averaged about 12,211 million gallons per day (Mgal/d) of freshwater for offstream uses?22 percent more than the 1995 estimate. The 2000 estimate is nearly the same as the estimate for 1980, the highest year of record, with 12,260 Mgal/d. The reuse potential of water from the Tennessee River is high because most of the water withdrawn for offstream use is returned to the river system. Besides water quality, reuse potential reflects the quantity of water available for subsequent uses and is gaged by consumptive use, which is the difference between water withdrawals and return flow. For the Tennessee River watershed, return flow was estimated to be 11,562 Mgal/d, or 95 percent of the water withdrawn during 2000. Total consumptive use accounts for the remaining 5 percent, or 649 Mgal/d. Estimates of water withdrawals by source indicate that during 2000, withdrawals from surface water accounted for 98 percent of the total withdrawals, or 11,996 Mgal/d, 23 percent more than during 1995. Total ground-water withdrawals during 2000 were 215 Mgal/d, or 17 percent less than during 1995. During 2000, thermoelectric power withdrawals were estimated to be 10,276 Mgal/d; industrial, 1,205 Mgal/d; public supply, 662 Mgal/d; and irrigation, 68.9 Mgal/d. Return flows were estimated to be: thermoelectric power, 10,244 Mgal/d; industrial, 942 Mgal/d; and public supply, 377 Mgal/d. Consumptive use was estimated to be: thermoelectric power, 32.2 Mgal/d; industrial, 263 Mgal/d; public supply, 285 Mgal/d; and irrigation, 68.9 Mgal/d. Each category of use affects the reuse potential of the return flows differently. The consumptive use in the river is comparatively small because most of the water withdrawn from the Tennessee River watershed is used for once-through cooling for the thermoelectric power and industrial sectors. Average per capita use for all offstream uses was 2,710 gallons per day per person in 2000, compared to the record high of 3,200 in 1975 and 1980. The intensity of use for the Tennessee River watershed as measured as a function of area was 298,489 gallons per day per square mile in 2000. In 2030, water withdrawals are projected to increase by about 15 percent to 13,990 Mgal/d. By category, water withdrawals are projected to increase as follows: thermoelectric power, 11 percent or 1,152 Mgal/d; industry, 31 percent or 368 Mgal/d; public supply, 35 percent or 232 Mgal/d; and irrigation, 37 percent or 25.2 Mgal/d. Total consumptive use is projected to increase about 51 percent or 334 Mgal/d to 980 Mgal/d. Per capita use in 2030 is calculated to be about 2,370 gallons per day, about 26 percent less than in 1980. Water transfers to the Tennessee-Tombigbee waterway for navigation lockages were estimated as 200 Mgal/d for 2000 and 800 Mgal/d for 2030. Water transfers for hydropower commitments through Barkley Canal averaged 3,361 Mgal/d for 2000 and are estimated to be an average of 4,524 Mgal/d in 2030.

An inter-lighting interference cancellation scheme for MISO-VLC systems

NASA Astrophysics Data System (ADS)

Kim, Kyuntak; Lee, Kyujin; Lee, Kyesan

2017-08-01

In this paper, we propose an inter-lighting interference cancellation (ILIC) scheme to reduce the interference between adjacent light-emitting diodes (LEDs) and enhance the transmission capacity of multiple-input-single-output (MISO)-visible light communication (VLC) systems. In indoor environments, multiple LEDs have normally been used as lighting sources, allowing the design of MISO-VLC systems. To enhance the transmission capacity, different data should be simultaneously transmitted from each LED; however, that can lead to interference between adjacent LEDs. In that case, relatively low-received power signals are subjected to large interference because wireless optical systems generally use intensity modulation and direct detection. Thus, only the signal with the highest received power can be detected, while the other received signals cannot be detected. To solve this problem, we propose the ILIC scheme for MISO-VLC systems. The proposed scheme preferentially detects the highest received power signal, and this signal is referred as interference signal by an interference component generator. Then, relatively low-received power signal can be detected by cancelling the interference signal from the total received signals. Therefore, the performance of the proposed scheme can improve the total average bit error rate and throughput of a MISO-VLC system.

Transcranial measurements of the acoustic field produced by a low frequency focused ultrasound system

NASA Astrophysics Data System (ADS)

Voie, Arne; Fisher, David; Ahadi, Golnaz; Hölscher, Thilo

2012-11-01

The purpose of this study was to ascertain the effects of the skull on the location, shape and power of the acoustic field produced by a 150 mm radius hemispherical array operating at 220 kHz. We wanted to determine whether phase aberrations were significant at this frequency, the amount of attenuation, and whether CT data could be predictive of the trans-skull field. The effects of five calvaria were evaluated. Acoustic field data and CT scans for each skull specimen were imported into MATLAB® for measurements and visualization in two and three dimensions. We examined the effects of skull density, porosity, thickness, and sonication incident angles, and estimated the relative contributions of longitudinal and shear transmission to the total transmitted power. Power transmission through the skulls varied between 4% and 23% (mean: 12%). The range of focal position shifts was from 0.50 mm to 4.32 mm (mean: 1.95 mm). The 3 dB dimensions of the focused ultrasound (FUS) intensity focal volume increased on average by 39% (low: 4%, high: 122%). The 6 dB pressure focal volume increased by an average of 130 ± 75%. In general, the main effects of the skulls were power reduction, field dispersion and slight shift of focal peak location.

Comparison of the backward overhead medicine ball throw to power production in college football players.

PubMed

Mayhew, Jerry L; Bird, Michael; Cole, Mary L; Koch, Alex J; Jacques, Jeff A; Ware, John S; Buford, Brittney N; Fletcher, Kate M

2005-08-01

The purpose of this study was to determine the relationship of the backward overhead medicine ball (BOMB) throw to power production in college football players. Forty National Collegiate Athletic Association Division II college football players were studied at the end of an 8-week off-season conditioning program for power output determined from a countermovement vertical jump on a force plate and for maximal distance in the standing BOMB throw. Although the reliability of the BOMB test was high (interclass correlation coefficient = 0.86), there was a significant learning effect across 3 trials (p < 0.01). Peak and average powers generated during the vertical jump correlated moderately but significantly with the best BOMB throw distance (r = 0.59 and 0.63, respectively). Considering power relative to body mass or lean body mass failed to produce significant correlations with BOMB throw distance (r = 0.27 and 0.28, respectively). Therefore, the BOMB throw may have limited potential as a predictor of total body explosive power in college football players.

Amplitude and phase fluctuations of Van der Pol oscillator under external random forcing

NASA Astrophysics Data System (ADS)

Singh, Aman K.; Yadava, R. D. S.

2018-05-01

The paper presents an analytical study of noise in Van der Pol oscillator output subjected to an external force noise assumed to be characterized by delta function (white noise). The external fluctuations are assumed to be small in comparison to the average response of the noise free system. The autocorrelation function and power spectrum are calculated under the condition of weak nonlinearity. The latter ensures limit cycle oscillations. The total spectral power density is dominated by the contributions from the phase fluctuations. The amplitude fluctuations are at least two orders of magnitude smaller. The analysis is shown to be useful to interpretation microcantilever based biosensing data.

GaAs laser diode pumped Nd:YAG laser

NASA Technical Reports Server (NTRS)

Conant, L. C.; Reno, C. W.

1974-01-01

A 1.5-mm by 3-cm neodymium-ion doped YAG laser rod has been side pumped using a GaAs laser diode array tuned to the 8680-A absorption line, achieving a multimode average output power of 120 mW for a total input power of 20 W to the final-stage laser diode drivers. The pumped arrangement was designed to take advantage of the high brightness of a conventional GaAs array as a linear source by introducing the pump light through a slit into a close-wrapped gold coated pump cavity. This cavity forms an integrating chamber for the pump light.

Estimation of soft X-ray and EUV transition radiation power emitted from the MIRRORCLE-type tabletop synchrotron.

PubMed

Toyosugi, N; Yamada, H; Minkov, D; Morita, M; Yamaguchi, T; Imai, S

2007-03-01

The tabletop synchrotron light sources MIRRORCLE-6X and MIRRORCLE-20SX, operating at electron energies E(el) = 6 MeV and E(el) = 20 MeV, respectively, can emit powerful transition radiation (TR) in the extreme ultraviolet (EUV) and the soft X-ray regions. To clarify the applicability of these soft X-ray and EUV sources, the total TR power has been determined. A TR experiment was performed using a 385 nm-thick Al foil target in MIRRORCLE-6X. The angular distribution of the emitted power was measured using a detector assembly based on an NE102 scintillator, an optical bundle and a photomultiplier. The maximal measured total TR power for MIRRORCLE-6X is P(max) approximately equal 2.95 mW at full power operation. Introduction of an analytical expression for the lifetime of the electron beam allows calculation of the emitted TR power by a tabletop synchrotron light source. Using the above measurement result, and the theoretically determined ratio between the TR power for MIRRORCLE-6X and MIRRORCLE-20SX, the total TR power for MIRRORCLE-20SX can be obtained. The one-foil TR target thickness is optimized for the 20 MeV electron energy. P(max) approximately equal 810 mW for MIRRORCLE-20SX is obtained with a single foil of 240 nm-thick Be target. The emitted bremsstrahlung is negligible with respect to the emitted TR for optimized TR targets. From a theoretically known TR spectrum it is concluded that MIRRORCLE-20SX can emit 150 mW of photons with E > 500 eV, which makes it applicable as a source for performing X-ray lithography. The average wavelength, \\overline\\lambda = 13.6 nm, of the TR emission of MIRRORCLE-20SX, with a 200 nm Al target, could provide of the order of 1 W EUV.

[Alcohol advertising in written mass media in Spain].

PubMed

Montes-Santiago, J; Alvarez Muñiz, M L; Baz Lomba, A

2007-03-01

Alcohol advertising is a powerful factor of incitation to consumption. We analyzed the alcohol advertising, especially that youth-focused, in written mass media in Spain during the period 2002-2006. Annual cross-sectional study of advertisements in 41 widely difused written mass media (average readers: 10,1 millions). Media admitting alcohol publicity were 29% in the whole. (2,9 millions of readers on average, 29% of total readers). Alcohol advertising constituted the 3,8% of global publicity and the 8,6% of the publicity in media admitting alcohol publicity. In this period only 4% of the media (2,4% of total readers) inserted antidrug campaigns. In brief, three out of 10 total readers and one out of 12 people older than 15 years suffered the impact of tobacco advertising. Young people were included in 33% of alcohol advertisements and 3 out of 6 of youth-oriented magazines permitted a such publicity. Alcohol publicity remains high in written mass media in Spain. By contrast few people received informative antidrug campaigns. Advertising was preferentially directed to young people.

An Empirical Study of Design Parameters for Assessing Differential Impacts for Students in Group Randomized Trials.

PubMed

Jaciw, Andrew P; Lin, Li; Ma, Boya

2016-10-18

Prior research has investigated design parameters for assessing average program impacts on achievement outcomes with cluster randomized trials (CRTs). Less is known about parameters important for assessing differential impacts. This article develops a statistical framework for designing CRTs to assess differences in impact among student subgroups and presents initial estimates of critical parameters. Effect sizes and minimum detectable effect sizes for average and differential impacts are calculated before and after conditioning on effects of covariates using results from several CRTs. Relative sensitivities to detect average and differential impacts are also examined. Student outcomes from six CRTs are analyzed. Achievement in math, science, reading, and writing. The ratio of between-cluster variation in the slope of the moderator divided by total variance-the "moderator gap variance ratio"-is important for designing studies to detect differences in impact between student subgroups. This quantity is the analogue of the intraclass correlation coefficient. Typical values were .02 for gender and .04 for socioeconomic status. For studies considered, in many cases estimates of differential impact were larger than of average impact, and after conditioning on effects of covariates, similar power was achieved for detecting average and differential impacts of the same size. Measuring differential impacts is important for addressing questions of equity, generalizability, and guiding interpretation of subgroup impact findings. Adequate power for doing this is in some cases reachable with CRTs designed to measure average impacts. Continuing collection of parameters for assessing differential impacts is the next step. © The Author(s) 2016.

Statistics of the radiated field of a space-to-earth microwave power transfer system

NASA Technical Reports Server (NTRS)

Stevens, G. H.; Leininger, G.

1976-01-01

Statistics such as average power density pattern, variance of the power density pattern and variance of the beam pointing error are related to hardware parameters such as transmitter rms phase error and rms amplitude error. Also a limitation on spectral width of the phase reference for phase control was established. A 1 km diameter transmitter appears feasible provided the total rms insertion phase errors of the phase control modules does not exceed 10 deg, amplitude errors do not exceed 10% rms, and the phase reference spectral width does not exceed approximately 3 kHz. With these conditions the expected radiation pattern is virtually the same as the error free pattern, and the rms beam pointing error would be insignificant (approximately 10 meters).

Assessment of Energy Production Potential from Ocean Currents along the United States Coastline

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

Haas, Kevin

Increasing energy consumption and depleting reserves of fossil fuels have resulted in growing interest in alternative renewable energy from the ocean. Ocean currents are an alternative source of clean energy due to their inherent reliability, persistence and sustainability. General ocean circulations exist in the form of large rotating ocean gyres, and feature extremely rapid current flow in the western boundaries due to the Coriolis Effect. The Gulf Stream system is formed by the western boundary current of the North Atlantic Ocean that flows along the east coastline of the United States, and therefore is of particular interest as a potentialmore » energy resource for the United States. This project created a national database of ocean current energy resources to help advance awareness and market penetration in ocean current energy resource assessment. The database, consisting of joint velocity magnitude and direction probability histograms, was created from data created by seven years of numerical model simulations. The accuracy of the database was evaluated by ORNL?s independent validation effort documented in a separate report. Estimates of the total theoretical power resource contained in the ocean currents were calculated utilizing two separate approaches. Firstly, the theoretical energy balance in the Gulf Stream system was examined using the two-dimensional ocean circulation equations based on the assumptions of the Stommel model for subtropical gyres with the quasi-geostrophic balance between pressure gradient, Coriolis force, wind stress and friction driving the circulation. Parameters including water depth, natural dissipation rate and wind stress are calibrated in the model so that the model can reproduce reasonable flow properties including volume flux and energy flux. To represent flow dissipation due to turbines additional turbine drag coefficient is formulated and included in the model. Secondly, to determine the reasonableness of the total power estimates from the Stommel model and to help determine the size and capacity of arrays necessary to extract the maximum theoretical power, further estimates of the available power based on the distribution of the kinetic power density in the undisturbed flow was completed. This used estimates of the device spacing and scaling to sum up the total power that the devices would produce. The analysis has shown that considering extraction over a region comprised of the Florida Current portion of the Gulf Stream system, the average power dissipated ranges between 4-6 GW with a mean around 5.1 GW. This corresponds to an average of approximately 45 TWh/yr. However, if the extraction area comprises the entire portion of the Gulf Stream within 200 miles of the US coastline from Florida to North Carolina, the average power dissipated becomes 18.6 GW or 163 TWh/yr. A web based GIS interface, http://www.oceancurrentpower.gatech.edu/, was developed for dissemination of the data. The website includes GIS layers of monthly and yearly mean ocean current velocity and power density for ocean currents along the entire coastline of the United States, as well as joint and marginal probability histograms for current velocities at a horizontal resolution of 4-7 km with 10-25 bins over depth. Various tools are provided for viewing, identifying, filtering and downloading the data.« less

Operations of the External Conjugate-T Matching System for the A2 ICRH Antennas at JET

NASA Astrophysics Data System (ADS)

Monakhov, I.; Graham, M.; Blackman, T.; Mayoral, M.-L.; Nightingale, M.; Sheikh, H.; Whitehurst, A.

2009-11-01

The External Conjugate-T (ECT) matching system was successfully commissioned on two A2 ICRH antennas at JET in 2009. The system allows trip-free injection of RF power into ELMy H-mode plasmas in the 32-52 MHz band without antenna phasing restrictions. The ECT demonstrates robust and predictable performance and high load-tolerance during routine operations, injecting up to 4 MW average power into H-mode plasma with Type-I ELMs. The total power coupled to ELMy plasma by all the A2 antennas using the ECT and 3dB systems has been increased to 7 MW. Antenna arcing during ELMs has been identified as a new challenge to high-power ICRH operations in H-mode plasma. The implemented Advanced Wave Amplitude Comparison System (AWACS) has proven to be an efficient protection tool for the ECT scheme.

Intermediate photovoltaic system application experiment operational performance report. Volume 6: Beverly High School, Beverly, Mass.

NASA Astrophysics Data System (ADS)

1982-03-01

Performance data are given for the month of February, 1982 for a photovoltaic power supply at a Massachusetts high school. Data given include: monthly and daily electrical energy yield; monthly and daily insolation; monthly and daily array efficiency; energy production as a function of power level, voltage, cell temperature, and hour of day; insolation as a function of hour of the day; input, output and efficiency for each of two power conditioning units and for the total power conditioning system; energy supplied to the load by the photovoltaic system and by the grid; photovoltaic system efficiency; dollar value of the energy supplied by the photovoltaic system; capacity factor; daily photovoltaic energy to load; daily system availability and hours of daylight; heating and cooling degree days; hourly cell temperature, ambient temperature, wind speed, and insolation; average monthly wind speed; wind direction distribution; and daily data acquisition mode and recording interval plot.

Operations of the External Conjugate-T Matching System for the A2 ICRH Antennas at JET

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

Monakhov, I.; Graham, M.; Blackman, T.

2009-11-26

The External Conjugate-T (ECT) matching system was successfully commissioned on two A2 ICRH antennas at JET in 2009. The system allows trip-free injection of RF power into ELMy H-mode plasmas in the 32-52 MHz band without antenna phasing restrictions. The ECT demonstrates robust and predictable performance and high load-tolerance during routine operations, injecting up to 4 MW average power into H-mode plasma with Type-I ELMs. The total power coupled to ELMy plasma by all the A2 antennas using the ECT and 3dB systems has been increased to 7 MW. Antenna arcing during ELMs has been identified as a new challengemore » to high-power ICRH operations in H-mode plasma. The implemented Advanced Wave Amplitude Comparison System (AWACS) has proven to be an efficient protection tool for the ECT scheme.« less

Comprehensive assessment of the effective scope of modernization of thermal power plants to substantiate the rational structure of the generating capacities for the future until 2035

NASA Astrophysics Data System (ADS)

Veselov, F. V.; Erokhina, I. V.; Makarova, A. S.; Khorshev, A. A.

2017-03-01

The article deals with issues of technical and economic substantiation of priorities and scopes of modernizing the existing thermal power plants (TPPs) in Russia to work out long-term forecasts of the development of the industry. The current situation in the TPP modernization trends is analyzed. The updated initial figures of the capital and operation costs are presented and the obtained estimates of the comparative efficiency of various investment decisions on modernization and equipment replacement at gas-and-oil-burning and coal-fired TPPs with regard to the main zones of the national Unified Power System (UPS) of Russia are cited. The results of optimization of the generating capacity structure underlie a study of alternative TPP modernization strategies that differ in the scope of switching to new technologies, capital intensity, and energy efficiency (decrease in the average heat rate). To provide an integral economic assessment of the above strategies, the authors modified the traditional approach based on determination of the overall discounted costs of power supply (least-cost planning) supplemented with a comparison by the weighted average wholesale price of the electricity. A method for prediction of the wholesale price is proposed reasoning from the direct and dual solutions of the optimization problem. The method can be adapted to various combinations of the mechanisms of payment for the electricity and the capacity on the basis of marginal and average costs. Energy and economic analysis showed that the opposite effects of reduction in the capital investment and fuel saving change in a nonlinear way as the scope of the switch to more advanced power generation technologies at the TPPs increases. As a consequence, a strategy for modernization of the existing power plants rational with respect to total costs of the power supply and wholesale electricity prices has been formulated. The strategy combines decisions on upgrade and replacement of the equipment at the existing power plants of various types. The basic parameters of the strategy for the future until 2035 are provided.

Development of novel high power-short time (HPST) microwave assisted commercial decontamination process for dried turmeric powder (Curcuma Longa L.).

PubMed

Behera, G; Sutar, P P; Aditya, S

2017-11-01

The commercially available dry turmeric powder at 10.34% d.b. moisture content was decontaminated using microwaves at high power density for short time. To avoid the loss of moisture from turmeric due to high microwave power, the drying kinetics were modelled and considered during optimization of microwave decontamination process. The effect of microwave power density (10, 33.5 and 57 W g -1 ), exposure time (10, 20 and 30 s) and thickness of turmeric layer (1, 2 and 3 mm) on total plate, total yeast and mold (YMC) counts, color change (∆E), average final temperature of the product (T af ), water activity (a w ), Page model rate constant (k) and total moisture loss (ML) was studied. The perturbation analysis was carried out for all variables. It was found that to achieve more than one log reduction in yeast and mold count, a substantial reduction in moisture content takes place leading to the reduced output. The microwave power density significantly affected the YMC, T af and a w of turmeric powder. But the thickness of sample and microwave exposure time showed effect only on T af , a w and ML. The colour of turmeric and Page model rate constant were not significantly changed during the process as anticipated. The numerical optimization was done at 57.00 W g -1 power density, 1.64 mm thickness of sample layer and 30 s exposure time. It resulted into 1.6 × 10 7 CFU g -1 YMC, 82.71 °C T af , 0.383 a w and 8.41% (d.b.) final moisture content.

Estimated metabolic and mechanical demands during different small-sided games in elite soccer players.

PubMed

Gaudino, Paolo; Alberti, Giampietro; Iaia, F Marcello

2014-08-01

The present study examined the extent to which game format (possession play, SSG-P and game with regular goals and goalkeepers, SSG-G) and the number of players (5, 7 and 10 a-side) influence the physical demands of small-sided soccer games (SSGs) in elite soccer players. Training data were collected during the in-season period from 26 English Premier League outfield players using global positioning system technology. Total distance covered, distance at different speed categories and maximal speed were calculated. In addition, we focused on changes in velocity by reporting the number of accelerations and decelerations carried out during the SSGs (divided in two categories: moderate and high) and the absolute maximal values of acceleration and deceleration achieved. By taking into account these parameters besides speed and distance values, estimated energy expenditure and average metabolic power and distance covered at different metabolic power categories were calculated. All variables were normalized by time (i.e., 4min). The main findings were that the total distance, distances run at high speed (>14.4kmh(-1)) as well as absolute maximum velocity, maximum acceleration and maximum deceleration increased with pitch size (10v10>7v7>5v5; p<.05). Furthermore, total distance, very high (19.8-25.2kmh(-1)) and maximal (>25.2kmh(-1)) speed distances, absolute maximal velocity and maximum acceleration and deceleration were higher in SSG-G than in SSG-P (p<.001). On the other hand, the number of moderate (2-3ms(-2)) accelerations and decelerations as well as the total number of changes in velocity were greater as the pitch dimensions decreased (i.e., 5v5>7v7>10v10; p<.001) in both SSG-G and SSG-P. In addition, predicted energy cost, average metabolic power and distance covered at every metabolic power categories were higher in SSG-P compared to SSG-G and in big than in small pitch areas (p<.05). A detailed analysis of these drills is pivotal in contemporary football as it enables an in depth understanding of the workload imposed on each player which consequently has practical implications for the prescription of the adequate type and amount of stimulus during exercise training. Copyright © 2014 Elsevier B.V. All rights reserved.

Comparison of two U.S. power-plant carbon dioxide emissions data sets

USGS Publications Warehouse

Ackerman, K.V.; Sundquist, E.T.

2008-01-01

Estimates of fossil-fuel CO2 emissions are needed to address a variety of climate-change mitigation concerns over a broad range of spatial and temporal scales. We compared two data sets that report power-plant CO 2 emissions in the conterminous U.S. for 2004, the most recent year reported in both data sets. The data sets were obtained from the Department of Energy's Energy Information Administration (EIA) and the Environmental Protection Agency's eGRID database. Conterminous U.S. total emissions computed from the data sets differed by 3.5% for total plant emissions (electricity plus useful thermal output) and 2.3% for electricity generation only. These differences are well within previous estimates of uncertainty in annual U.S. fossil-fuel emissions. However, the corresponding average absolute differences between estimates of emissions from individual power plants were much larger, 16.9% and 25.3%, respectively. By statistical analysis, we identified several potential sources of differences between EIA and eGRID estimates for individual plants. Estimates that are based partly or entirely on monitoring of stack gases (reported by eGRID only) differed significantly from estimates based on fuel consumption (as reported by EIA). Differences in accounting methods appear to explain differences in estimates for emissions from electricity generation from combined heat and power plants, and for total and electricity generation emissions from plants that burn nonconventional fuels (e.g., biomass). Our analysis suggests the need for care in utilizing emissions data from individual power plants, and the need for transparency in documenting the accounting and monitoring methods used to estimate emissions.

Leg exoskeleton reduces the metabolic cost of human hopping.

PubMed

Grabowski, Alena M; Herr, Hugh M

2009-09-01

During bouncing gaits such as hopping and running, leg muscles generate force to enable elastic energy storage and return primarily from tendons and, thus, demand metabolic energy. In an effort to reduce metabolic demand, we designed two elastic leg exoskeletons that act in parallel with the wearer's legs; one exoskeleton consisted of a multiple leaf (MLE) and the other of a single leaf (SLE) set of fiberglass springs. We hypothesized that hoppers, hopping on both legs, would adjust their leg stiffness while wearing an exoskeleton so that the combination of the hopper and exoskeleton would behave as a linear spring-mass system with the same total stiffness as during normal hopping. We also hypothesized that decreased leg force generation while wearing an exoskeleton would reduce the metabolic power required for hopping. Nine subjects hopped in place at 2.0, 2.2, 2.4, and 2.6 Hz with and without an exoskeleton while we measured ground reaction forces, exoskeletal compression, and metabolic rates. While wearing an exoskeleton, hoppers adjusted their leg stiffness to maintain linear spring-mass mechanics and a total stiffness similar to normal hopping. Without accounting for the added weight of each exoskeleton, wearing the MLE reduced net metabolic power by an average of 6% and wearing the SLE reduced net metabolic power by an average of 24% compared with hopping normally at frequencies between 2.0 and 2.6 Hz. Thus, when hoppers used external parallel springs, they likely decreased the mechanical work performed by the legs and substantially reduced metabolic demand compared with hopping without wearing an exoskeleton.

Job embeddedness factors as a predictor of turnover intention among infection control nurses in Korea.

PubMed

Choi, Jeong Sil; Kim, Kyung Mi

2015-11-01

Job embeddedness indicates the degree to which an employee of an organization intends to remain in his or her position at that organization. This study examined how job embeddedness affects infection control nurses' turnover intention along with general characteristics, job satisfaction, and perceived job alternatives. We collected data from a total of 133 infection control nurses using self-reporting questionnaire methods. All questions were answered on a 5-point Likert scale. The average turnover intention was 3.01 ± 0.72 (100-point conversion, 60.2%), and average job satisfaction was 3.48 ± 0.79 (100-point conversion, 69.6%). The average perceived availability of job alternatives was 3.02 ± 0.78 (100-point conversion, 60.4%), and average job embeddedness was 3.33 ± 0.57 (100-point conversion, 66.6%). Predictors of turnover intention were monthly income, perceived availability of job alternatives, and job embeddedness. Job embeddedness among predictors has high explanatory power as a predictor of infection control nurses' turnover intention. Through this study we identified predictors of turnover intention and found that job embeddedness among predictors has high explanatory power as a predictor of infection control nurses' turnover intention. Strategies to enhance infection control nurses' job embeddedness are needed. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

152 W average power Tm-doped fiber CPA system.

PubMed

Stutzki, Fabian; Gaida, Christian; Gebhardt, Martin; Jansen, Florian; Wienke, Andreas; Zeitner, Uwe; Fuchs, Frank; Jauregui, Cesar; Wandt, Dieter; Kracht, Dietmar; Limpert, Jens; Tünnermann, Andreas

2014-08-15

A high-power thulium (Tm)-doped fiber chirped-pulse amplification system emitting a record compressed average output power of 152 W and 4 MW peak power is demonstrated. This result is enabled by utilizing Tm-doped photonic crystal fibers with mode-field diameters of 35 μm, which mitigate detrimental nonlinearities, exhibit slope efficiencies of more than 50%, and allow for reaching a pump-power-limited average output power of 241 W. The high-compression efficiency has been achieved by using multilayer dielectric gratings with diffraction efficiencies higher than 98%.

Standard-Cell, Open-Architecture Power Conversion Systems

DTIC Science & Technology

2005-10-01

TLmax Maximum junction temperature 423 OK Table 5. 9. PEBB average model description in VTB. Terminal Type Name - 4 -, A Power DC Bus + B Power AC Pole...5 A. Switching models ........................................................................................ 5 B. Average ...11-6 IV. Average Modeling of PEBB-Based Converters...................................................... 11-10 0 IV. 1.Voltage

Absorption and scattering of laser radiation by the diffusion flame of aviation kerosene

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

Gvozdev, S V; Glova, A F; Dubrovskii, V Yu

2012-04-30

The absorption coefficient of the radiation of a repetitively pulsed Nd : YAG laser with an average output power up to 6 W and of a cw ytterbium optical fibre laser with an output power up to 3 kW was measured in the diffusion flame of aviation kerosene burning on a free surface in the atmospheric air. The absorption coefficient as a function of flame length, radiation power, and radiation intensity, which was varied in the {approx}10{sup 3} - 5 Multiplication-Sign 10{sup 4} W cm{sup -2} range, was obtained for two distances (1 and 2 cm) between the laser beammore » axis and the surface. The coefficient of radiation absorption by kerosene flame was compared with that in ethanol and kerosene - ethanol mixture flames. The radiation power scattered by a small segment of the kerosene flame irradiated by Nd : YAG laser radiation was measured as a function of longitudinal and azimuthal coordinates. An estimate was made of the total scattered radiation power.« less

Absorption and scattering of laser radiation by the diffusion flame of aviation kerosene

NASA Astrophysics Data System (ADS)

Gvozdev, S. V.; Glova, A. F.; Dubrovskii, V. Yu; Durmanov, S. T.; Krasyukov, A. G.; Lysikov, A. Yu; Smirnov, G. V.; Solomakhin, V. B.

2012-04-01

The absorption coefficient of the radiation of a repetitively pulsed Nd : YAG laser with an average output power up to 6 W and of a cw ytterbium optical fibre laser with an output power up to 3 kW was measured in the diffusion flame of aviation kerosene burning on a free surface in the atmospheric air. The absorption coefficient as a function of flame length, radiation power, and radiation intensity, which was varied in the ~103 — 5×104 W cm-2 range, was obtained for two distances (1 and 2 cm) between the laser beam axis and the surface. The coefficient of radiation absorption by kerosene flame was compared with that in ethanol and kerosene — ethanol mixture flames. The radiation power scattered by a small segment of the kerosene flame irradiated by Nd : YAG laser radiation was measured as a function of longitudinal and azimuthal coordinates. An estimate was made of the total scattered radiation power.

Preparation of TiN films by reactive high-power pulsed sputtering Penning discharges

NASA Astrophysics Data System (ADS)

Kimura, Takashi; Yoshida, Ryo; Mishima, Toshihiko; Azuma, Kingo; Nakao, Setsuo

2018-06-01

Titanium nitride (TiN) films are prepared by reactive high-power pulsed sputtering Penning discharges at a total pressure of 0.7 Pa and an average power of 60 W, where the nitrogen fraction is varied up to 15%. The peak value of the instantaneous power ranges between 3 and 14 kW, and the peak power density ranges between 0.3 and 1.2 kW cm‑2. The hardness of TiN films is higher than 22 GPa at the nitrogen fractions lower than 10% and it reaches 31 GPa at a nitrogen fraction of 5%. The X-ray diffraction peak of TiN(111) texture is observed for all prepared films, showing the grain size of about 10 nm. In X-ray photoelectron spectroscopy, oxygen is mainly bonded to titanium, but the intensity of the TiN bond is dominant in the entire Ti 2p spectrum. The intensity ratio of N 1s to Ti 2p ranges between 0.85 and 0.95.

Do trout swim better than eels? Challenges for estimating performance based on the wake of self-propelled bodies

NASA Astrophysics Data System (ADS)

Tytell, Eric D.

2007-11-01

Engineers and biologists have long desired to compare propulsive performance for fishes and underwater vehicles of different sizes, shapes, and modes of propulsion. Ideally, such a comparison would be made on the basis of either propulsive efficiency, total power output or both. However, estimating the efficiency and power output of self-propelled bodies, and particularly fishes, is methodologically challenging because it requires an estimate of thrust. For such systems traveling at a constant velocity, thrust and drag are equal, and can rarely be separated on the basis of flow measured in the wake. This problem is demonstrated using flow fields from swimming American eels, Anguilla rostrata, measured using particle image velocimetry (PIV) and high-speed video. Eels balance thrust and drag quite evenly, resulting in virtually no wake momentum in the swimming (axial) direction. On average, their wakes resemble those of self-propelled jet propulsors, which have been studied extensively. Theoretical studies of such wakes may provide methods for the estimation of thrust separately from drag. These flow fields are compared with those measured in the wakes of rainbow trout, Oncorhynchus mykiss, and bluegill sunfish, Lepomis macrochirus. In contrast to eels, these fishes produce wakes with axial momentum. Although the net momentum flux must be zero on average, it is neither spatially nor temporally homogeneous; the heterogeneity may provide an alternative route for estimating thrust. This review shows examples of wakes and velocity profiles from the three fishes, indicating challenges in estimating efficiency and power output and suggesting several routes for further experiments. Because these estimates will be complicated, a much simpler method for comparing performance is outlined, using as a point of comparison the power lost producing the wake. This wake power, a component of the efficiency and total power, can be estimated in a straightforward way from the flow fields. Although it does not provide complete information about the performance, it can be used to place constraints on the relative efficiency and cost of transport for the fishes.

Do trout swim better than eels? Challenges for estimating performance based on the wake of self-propelled bodies

NASA Astrophysics Data System (ADS)

Tytell, Eric D.

Engineers and biologists have long desired to compare propulsive performance for fishes and underwater vehicles of different sizes, shapes, and modes of propulsion. Ideally, such a comparison would be made on the basis of either propulsive efficiency, total power output or both. However, estimating the efficiency and power output of self-propelled bodies, and particularly fishes, is methodologically challenging because it requires an estimate of thrust. For such systems traveling at a constant velocity, thrust and drag are equal, and can rarely be separated on the basis of flow measured in the wake. This problem is demonstrated using flow fields from swimming American eels, Anguilla rostrata, measured using particle image velocimetry (PIV) and high-speed video. Eels balance thrust and drag quite evenly, resulting in virtually no wake momentum in the swimming (axial) direction. On average, their wakes resemble those of self-propelled jet propulsors, which have been studied extensively. Theoretical studies of such wakes may provide methods for the estimation of thrust separately from drag. These flow fields are compared with those measured in the wakes of rainbow trout, Oncorhynchus mykiss, and bluegill sunfish, Lepomis macrochirus. In contrast to eels, these fishes produce wakes with axial momentum. Although the net momentum flux must be zero on average, it is neither spatially nor temporally homogeneous; the heterogeneity may provide an alternative route for estimating thrust. This review shows examples of wakes and velocity profiles from the three fishes, indicating challenges in estimating efficiency and power output and suggesting several routes for further experiments. Because these estimates will be complicated, a much simpler method for comparing performance is outlined, using as a point of comparison the power lost producing the wake. This wake power, a component of the efficiency and total power, can be estimated in a straightforward way from the flow fields. Although it does not provide complete information about the performance, it can be used to place constraints on the relative efficiency and cost of transport for the fishes.

Field data collection of miscellaneous electrical loads in Northern California: Initial results

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

Greenblatt, Jeffery B.; Pratt, Stacy; Willem, Henry

This report describes efforts to measure energy use of miscellaneous electrical loads (MELs) in 880 San Francisco Bay Area homes during the summer of 2012. Ten regions were selected for metering: Antioch, Berkeley, Fremont, Livermore, Marin County (San Rafael, Novato, Fairfax, and Mill Valley), Oakland/Emeryville, Pleasanton, Richmond, San Leandro, and Union City. The project focused on three major categories of devices: entertainment (game consoles, set-top boxes, televisions and video players), home office (computers, monitors and network equipment), and kitchen plug-loads (coffee/espresso makers, microwave ovens/toaster ovens/toasters, rice/slow cookers and wine chillers). These categories were important to meter because they either dominatedmore » the estimated overall energy use of MELs, are rapidly changing, or there are very little energy consumption data published. A total of 1,176 energy meters and 143 other sensors were deployed, and 90% of these meters and sensors were retrieved. After data cleaning, we obtained 711 valid device energy use measurements, which were used to estimate, for a number of device subcategories, the average time spent in high power, low power and “off” modes, the average energy use in each mode, and the average overall energy use. Consistent with observations made in previous studies, we find on average that information technology (IT) devices (home entertainment and home office equipment) consume more energy (15.0 and 13.0 W, respectively) than non-IT devices (kitchen plug-loads; 4.9 W). Opportunities for energy savings were identified in almost every device category, based on the time spent in various modes and/or the power levels consumed in those modes. Future reports will analyze the collected data in detail by device category and compare results to those obtained from prior studies.« less

High-Average Power Broadband 18-Beam Klystron Circuit and Collector Designs

DTIC Science & Technology

2008-04-01

high -average power S - band multiple-beam klystron are presented. The klystron will be powered by the recently completed 41.6 A, 42...al., “ High - power Four-cavity S - band multiple-beam klystron design,” IEEE Trans. Plasma Science, vol. 33, pp. 1119-1135, April 2005. [3] D.K Abe, et...APR 2008 2. REPORT TYPE 3. DATES COVERED 00-00-2008 to 00-00-2008 4. TITLE AND SUBTITLE High -average Power Broadband 18-beam

Time Averaged Transmitter Power and Exposure to Electromagnetic Fields from Mobile Phone Base Stations

PubMed Central

Bürgi, Alfred; Scanferla, Damiano; Lehmann, Hugo

2014-01-01

Models for exposure assessment of high frequency electromagnetic fields from mobile phone base stations need the technical data of the base stations as input. One of these parameters, the Equivalent Radiated Power (ERP), is a time-varying quantity, depending on communication traffic. In order to determine temporal averages of the exposure, corresponding averages of the ERP have to be available. These can be determined as duty factors, the ratios of the time-averaged power to the maximum output power according to the transmitter setting. We determine duty factors for UMTS from the data of 37 base stations in the Swisscom network. The UMTS base stations sample contains sites from different regions of Switzerland and also different site types (rural/suburban/urban/hotspot). Averaged over all regions and site types, a UMTS duty factor F ≈ 0.32 ± 0.08 for the 24 h-average is obtained, i.e., the average output power corresponds to about a third of the maximum power. We also give duty factors for GSM based on simple approximations and a lower limit for LTE estimated from the base load on the signalling channels. PMID:25105551

Outdoor radiofrequency radiation levels in the West Bank-Palestine.

PubMed

Lahham, Adnan; Hammash, Alaa

2012-05-01

This work presents the results of exposure levels to radio frequency (RF) emission from different sources in the environment of the West Bank-Palestine. These RF emitters include FM and TV broadcasting stations and mobile phone base stations. Power densities were measured at 65 locations distributed over the West Bank area. These locations include mainly centres of the major cities. Also a 24 h activity level was investigated for a mobile phone base station to determine the maximum activity level for this kind of RF emitters. All measurements were conducted at a height of 1.7 m above ground level using hand held Narda SRM 3000 spectrum analyzer with isotropic antenna capable of collecting RF signals in the frequency band from 75 MHz to 3 GHz. The average value of power density resulted from FM radio broadcasting in all investigated locations was 0.148 μW cm(-2), from TV broadcasting was 0.007 μW cm(-2) and from mobile phone base station was 0.089 μW cm(-2). The maximum total exposure evaluated at any location was 3.86 μW cm(-2). The corresponding exposure quotient calculated for this site was 0.02. This value is well below unity indicating compliance with the International Commission on non-ionising Radiation protection guidelines. Contributions from all relevant RF sources to the total exposure were evaluated and found to be ~62 % from FM radio, 3 % for TV broadcasting and 35 % from mobile phone base stations. The average total exposure from all investigated RF sources was 0.37 μW cm(-2).

Lumen degradation analysis of LED lamps based on the subsystem isolation method.

PubMed

Ke, Hong-Liang; Hao, Jian; Tu, Jian-Hui; Miao, Pei-Xian; Wang, Chao-Quan; Cui, Jing-Zhong; Sun, Qiang; Sun, Ren-Tao

2018-02-01

The lumen degradation of LED lamps undergoing an accelerated aging test is investigated. The entire LED lamp is divided into three subsystems, namely, driver, lampshade, and LED light source. The parameters of output power [Watts (W)], transmittance (%), and lumen flux (lm) are adopted in the analysis of the degradation of the driver, lampshade, and LED light source, respectively. Two groups of LED lamps are aged under the ambient temperatures of 25°C and 85°C, respectively, with the aging time of 2000 h. The lumen degradation of the lamps is from 3.8% to 4.9% for the group under a temperature of 25°C and from 10.6% to 12.7% for the group under a temperature of 85°C. The LED light source is the most aggressive part of the three subsystems, which accounts for 70.5% of the lumen degradation of the LED lamp on average. The lampshade is the second degradation source, which causes 21.5% of the total amount on average. The driver is the third degradation source, which causes 6.5% under 25°C and 2.8% under 85°C of the total amount on average.

Approximating lens power.

PubMed

Kaye, Stephen B

2009-04-01

To provide a scalar measure of refractive error, based on geometric lens power through principal, orthogonal and oblique meridians, that is not limited to the paraxial and sag height approximations. A function is derived to model sections through the principal meridian of a lens, followed by rotation of the section through orthogonal and oblique meridians. Average focal length is determined using the definition for the average of a function. Average univariate power in the principal meridian (including spherical aberration), can be computed from the average of a function over the angle of incidence as determined by the parameters of the given lens, or adequately computed from an integrated series function. Average power through orthogonal and oblique meridians, can be similarly determined using the derived formulae. The widely used computation for measuring refractive error, the spherical equivalent, introduces non-constant approximations, leading to a systematic bias. The equations proposed provide a good univariate representation of average lens power and are not subject to a systematic bias. They are particularly useful for the analysis of aggregate data, correlating with biological treatment variables and for developing analyses, which require a scalar equivalent representation of refractive power.

A new study of shower age distribution in near vertical showers by EAS air shower array

NASA Technical Reports Server (NTRS)

Chaudhuri, N.; Basak, D. K.; Goswami, G. C.; Ghosh, B.

1984-01-01

The air shower array has been developed since it started operation in 1931. The array covering an area of 900 sq m now incorporates 21 particle density sampling detectors around two muon magnetic spectrographs. The air showers are detected in the size range 10 to the 4th power to 10 to the 6th power particles. A total of 11000 showers has so far been detected. Average values of shower age have been obtained in various shower size ranges to study the dependence of shower age on shower size. The core distance dependence of shower age parameter has also been analyzed for presentation.

Operational summary of an electric propulsion long term test facility

NASA Technical Reports Server (NTRS)

Trump, G. E.; James, E. L.; Bechtel, R. T.

1982-01-01

An automated test facility capable of simultaneously operating three 2.5 kW, 30-cm mercury ion thrusters and their power processors is described, along with a test program conducted for the documentation of thruster characteristics as a function of time. Facility controls are analog, with full redundancy, so that in the event of malfunction the facility automaticcally activates a backup mode and notifies an operator. Test data are recorded by a central data collection system and processed as daily averages. The facility has operated continuously for a period of 37 months, over which nine mercury ion thrusters and four power processor units accumulated a total of over 14,500 hours of thruster operating time.

Radiological effluents released and public doses from nuclear power plants in Korea.

PubMed

Son, Jung Kwon; Kim, Hee Geun; Kong, Tae Young; Ko, Jong Hyun; Lee, Goung Jin

2013-08-01

As of the end of 2010, there were 20 commercially operating nuclear reactors in Korea. Releases of radioactive effluents from nuclear power plants (NPPs) have increased continuously; the total radioactivity of effluent amount released in 2010 was 547.12 TBq. From 2001 to 2010, the annual average radioactivity of gaseous and liquid effluents per reactor was 11.61 TBq for pressurised water reactors and 118.12 TBq for pressurised heavy water reactors. Most of the radioactivity from gaseous and liquid effluents came from tritium. Based on the results of release trends and analyses, the characteristics of effluents have been investigated to improve the management of radioactive effluents from NPPs.

Estimation of average annual streamflows and power potentials for Alaska and Hawaii

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

Verdin, Kristine L.

2004-05-01

This paper describes the work done to develop average annual streamflow estimates and power potential for the states of Alaska and Hawaii. The Elevation Derivatives for National Applications (EDNA) database was used, along with climatic datasets, to develop flow and power estimates for every stream reach in the EDNA database. Estimates of average annual streamflows were derived using state-specific regression equations, which were functions of average annual precipitation, precipitation intensity, drainage area, and other elevation-derived parameters. Power potential was calculated through the use of the average annual streamflow and the hydraulic head of each reach, which is calculated from themore » EDNA digital elevation model. In all, estimates of streamflow and power potential were calculated for over 170,000 stream segments in the Alaskan and Hawaiian datasets.« less

Regional water consumption for hydro and thermal electricity generation in the United States

DOE PAGES

Lee, Uisung; Han, Jeongwoo; Elgowainy, Amgad; ...

2017-05-18

Water is an essential resource for most electric power generation technologies. Thermal power plants typically require a large amount of cooling water whose evaporation is regarded to be consumed. Hydropower plants result in evaporative water loss from the large surface areas of the storing reservoirs. This paper estimated the regional water consumption factors (WCFs) for thermal and hydro electricity generation in the United States, because the WCFs of these power plants vary by region and water supply and demand balance are of concern in many regions. For hydropower, total WCFs were calculated using a reservoir’s surface area, state-level water evaporation,more » and background evapotranspiration. Then, for a multipurpose reservoir, a fraction of its WCF was allocated to hydropower generation based on the share of the economic valuation of hydroelectricity among benefits from all purposes of the reservoir. For thermal power plants, the variations in WCFs by type of cooling technology, prime mover technology, and by region were addressed. The results show that WCFs for electricity generation vary significantly by region. Finally, the generation-weighted average WCFs of thermoelectricity and hydropower are 1.25 (range of 0.18–2.0) and 16.8 (range of 0.67–1194) L/kWh, respectively, and the generation-weighted average WCF by the U.S. generation mix in 2015 is estimated at 2.18 L/kWh.« less

Regional water consumption for hydro and thermal electricity generation in the United States

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

Lee, Uisung; Han, Jeongwoo; Elgowainy, Amgad

Water is an essential resource for most electric power generation technologies. Thermal power plants typically require a large amount of cooling water whose evaporation is regarded to be consumed. Hydropower plants result in evaporative water loss from the large surface areas of the storing reservoirs. This paper estimated the regional water consumption factors (WCFs) for thermal and hydro electricity generation in the United States, because the WCFs of these power plants vary by region and water supply and demand balance are of concern in many regions. For hydropower, total WCFs were calculated using a reservoir’s surface area, state-level water evaporation,more » and background evapotranspiration. Then, for a multipurpose reservoir, a fraction of its WCF was allocated to hydropower generation based on the share of the economic valuation of hydroelectricity among benefits from all purposes of the reservoir. For thermal power plants, the variations in WCFs by type of cooling technology, prime mover technology, and by region were addressed. The results show that WCFs for electricity generation vary significantly by region. Finally, the generation-weighted average WCFs of thermoelectricity and hydropower are 1.25 (range of 0.18–2.0) and 16.8 (range of 0.67–1194) L/kWh, respectively, and the generation-weighted average WCF by the U.S. generation mix in 2015 is estimated at 2.18 L/kWh.« less

Estimated use of water in the United States in 1970

USGS Publications Warehouse

Murray, Charles Richard; Reeves, E. Bodette

1972-01-01

The average annual streamflow--simplified measure of the total available water supply--is approximately 1,200 bgd in the conterminous United States. Total water withdrawn in 1970 for off-channel uses (withdrawals other than for hydroelectric power) amounted to about 30 percent of the average annual streamflow: 7 percent of the 1,200 bgd basic supply was consumed. However, comparisons of Water Resources Council regions indicate that the rate of withdrawal was higher than the locally dependable supply in the Middle Atlantic, Texas-Gulf, Rio Grande, Lower Colorado, and California-South Pacific regions. Consumption amounted to nearly 25 percent of withdrawals in the conterminous United States; however, fresh-water consumption amounted to only 14 percent of off-channel withdrawals in the 31 Eastern States and ranged from 30 percent to nearly 70 percent of off-channel withdrawals in the Water Resources Council regions in the West. In the Rio Grande and Lower Colorado regions, fresh-water consumption in 1970 exceeded the estimated dependable supply of fresh water.

An empirical method for determining average soil infiltration rates and runoff, Powder River structural basin, Wyoming

USGS Publications Warehouse

Rankl, James G.

1982-01-01

This report describes a method to estimate infiltration rates of soils for use in estimating runoff from small basins. Average rainfall intensity is plotted against storm duration on log-log paper. All rainfall events are designated as having either runoff or nonrunoff. A power-decay-type curve is visually fitted to separate the two types of rainfall events. This separation curve is an incipient-ponding curve and its equation describes infiltration parameters for a soil. For basins with more than one soil complex, only the incipient-ponding curve for the soil complex with the lowest infiltration rate can be defined using the separation technique. Incipient-ponding curves for soils with infiltration rates greater than the lowest curve are defined by ranking the soils according to their relative permeabilities and optimizing the curve position. A comparison of results for six basins produced computed total runoff for all events used ranging from 16.6 percent less to 2.3 percent more than measured total runoff. (USGS)

Wind speed statistics for Goldstone, California, anemometer sites

NASA Technical Reports Server (NTRS)

Berg, M.; Levy, R.; Mcginness, H.; Strain, D.

1981-01-01

An exploratory wind survey at an antenna complex was summarized statistically for application to future windmill designs. Data were collected at six locations from a total of 10 anemometers. Statistics include means, standard deviations, cubes, pattern factors, correlation coefficients, and exponents for power law profile of wind speed. Curves presented include: mean monthly wind speeds, moving averages, and diurnal variation patterns. It is concluded that three of the locations have sufficiently strong winds to justify consideration for windmill sites.

Analytical expressions for maximum wind turbine average power in a Rayleigh wind regime

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

Carlin, P.W.

Average or expectation values for annual power of a wind turbine in a Rayleigh wind regime are calculated and plotted as a function of cut-out wind speed. This wind speed is expressed in multiples of the annual average wind speed at the turbine installation site. To provide a common basis for comparison of all real and imagined turbines, the Rayleigh-Betz wind machine is postulated. This machine is an ideal wind machine operating with the ideal Betz power coefficient of 0.593 in a Rayleigh probability wind regime. All other average annual powers are expressed in fractions of that power. Cases consideredmore » include: (1) an ideal machine with finite power and finite cutout speed, (2) real machines operating in variable speed mode at their maximum power coefficient, and (3) real machines operating at constant speed.« less

A mechanism producing power law etc. distributions

NASA Astrophysics Data System (ADS)

Li, Heling; Shen, Hongjun; Yang, Bin

2017-07-01

Power law distribution is playing an increasingly important role in the complex system study. Based on the insolvability of complex systems, the idea of incomplete statistics is utilized and expanded, three different exponential factors are introduced in equations about the normalization condition, statistical average and Shannon entropy, with probability distribution function deduced about exponential function, power function and the product form between power function and exponential function derived from Shannon entropy and maximal entropy principle. So it is shown that maximum entropy principle can totally replace equal probability hypothesis. Owing to the fact that power and probability distribution in the product form between power function and exponential function, which cannot be derived via equal probability hypothesis, can be derived by the aid of maximal entropy principle, it also can be concluded that maximal entropy principle is a basic principle which embodies concepts more extensively and reveals basic principles on motion laws of objects more fundamentally. At the same time, this principle also reveals the intrinsic link between Nature and different objects in human society and principles complied by all.

Performance of arrays of direct-driven wave energy converters under optimal power take-off damping

NASA Astrophysics Data System (ADS)

Wang, Liguo; Engström, Jens; Leijon, Mats; Isberg, Jan

2016-08-01

It is well known that the total power converted by a wave energy farm is influenced by the hydrodynamic interactions between wave energy converters, especially when they are close to each other. Therefore, to improve the performance of a wave energy farm, the hydrodynamic interaction between converters must be considered, which can be influenced by the power take-off damping of individual converters. In this paper, the performance of arrays of wave energy converters under optimal hydrodynamic interaction and power take-off damping is investigated. This is achieved by coordinating the power take-off damping of individual converters, resulting in optimal hydrodynamic interaction as well as higher production of time-averaged power converted by the farm. Physical constraints on motion amplitudes are considered in the solution, which is required for the practical implementation of wave energy converters. Results indicate that the natural frequency of a wave energy converter under optimal damping will not vary with sea states, but the production performance of a wave energy farm can be improved significantly while satisfying the motion constraints.

Evaluation of Dynamic Channel and Power Assignment for Cognitive Networks

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

Syed A. Ahmad; Umesh Shukla; Ryan E. Irwin

2011-03-01

In this paper, we develop a unifying optimization formulation to describe the Dynamic Channel and Power Assignment (DCPA) problem and evaluation method for comparing DCPA algorithms. DCPA refers to the allocation of transmit power and frequency channels to links in a cognitive network so as to maximize the total number of feasible links while minimizing the aggregate transmit power. We apply our evaluation method to five algorithms representative of DCPA used in literature. This comparison illustrates the tradeoffs between control modes (centralized versus distributed) and channel/power assignment techniques. We estimate the complexity of each algorithm. Through simulations, we evaluate themore » effectiveness of the algorithms in achieving feasible link allocations in the network, as well as their power efficiency. Our results indicate that, when few channels are available, the effectiveness of all algorithms is comparable and thus the one with smallest complexity should be selected. The Least Interfering Channel and Iterative Power Assignment (LICIPA) algorithm does not require cross-link gain information, has the overall lowest run time, and highest feasibility ratio of all the distributed algorithms; however, this comes at a cost of higher average power per link.« less

Calm water resistance prediction of a bulk carrier using Reynolds averaged Navier-Stokes based solver

NASA Astrophysics Data System (ADS)

Rahaman, Md. Mashiur; Islam, Hafizul; Islam, Md. Tariqul; Khondoker, Md. Reaz Hasan

2017-12-01

Maneuverability and resistance prediction with suitable accuracy is essential for optimum ship design and propulsion power prediction. This paper aims at providing some of the maneuverability characteristics of a Japanese bulk carrier model, JBC in calm water using a computational fluid dynamics solver named SHIP Motion and OpenFOAM. The solvers are based on the Reynolds average Navier-Stokes method (RaNS) and solves structured grid using the Finite Volume Method (FVM). This paper comprises the numerical results of calm water test for the JBC model with available experimental results. The calm water test results include the total drag co-efficient, average sinkage, and trim data. Visualization data for pressure distribution on the hull surface and free water surface have also been included. The paper concludes that the presented solvers predict the resistance and maneuverability characteristics of the bulk carrier with reasonable accuracy utilizing minimum computational resources.

Evaluation of a multifiltration water reclamation subsystem to reclaim domestic clothes wash water

NASA Technical Reports Server (NTRS)

Hall, J. B., Jr.

1973-01-01

An evaluation has been performed of a multifiltration water reclamation subsystem to determine its capability to recover water from domestic clothes wash water. A total of 32.89 kg (72.5 lb) of clothes were washed during eight wash cycles which used 1.4 lb of detergent, 145 gallons of hot water and 133.9 gallons of cold water. Water recovered at a weighted average process rate of 3.81 gallons per hour met the majority of the 23 requirements established for potable water by the U.S. Public Health Service. Average power consumed during this evaluation was approximately 71 watt-hours per gallon of water recovered. Filter replacement, which was required primarily for the control of micro-organisms in the recovered water averaged 4.86 filters per 100 gallons of wash water processed. The subsystem removed approximately 98 percent and virtually 100 percent of the phosphates and surfactants, respectively, from the wash water.

Integrated unaligned resonant modulator tuning

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

Zortman, William A.; Lentine, Anthony L.

Methods and systems for tuning a resonant modulator are disclosed. One method includes receiving a carrier signal modulated by the resonant modulator with a stream of data having an approximately equal number of high and low bits, determining an average power of the modulated carrier signal, comparing the average power to a predetermined threshold, and operating a tuning device coupled to the resonant modulator based on the comparison of the average power and the predetermined threshold. One system includes an input structure, a plurality of processing elements, and a digital control element. The input structure is configured to receive, frommore » the resonant modulator, a modulated carrier signal. The plurality of processing elements are configured to determine an average power of the modulated carrier signal. The digital control element is configured to operate a tuning device coupled to the resonant modulator based on the average power of the modulated carrier signal.« less

Module failure isolation circuit for paralleled inverters. [preventing system failure during power conditioning for spacecraft applications

NASA Technical Reports Server (NTRS)

Nagano, S. (Inventor)

1979-01-01

A module failure isolation circuit is described which senses and averages the collector current of each paralled inverter power transistor and compares the collector current of each power transistor the average collector current of all power transistors to determine when the sensed collector current of a power transistor in any one inverter falls below a predetermined ratio of the average collector current. The module associated with any transistor that fails to maintain a current level above the predetermined radio of the average collector current is then shut off. A separate circuit detects when there is no load, or a light load, to inhibit operation of the isolation circuit during no load or light load conditions.

Analytical Assessment of the Relationship between 100MWp Large-scale Grid-connected Photovoltaic Plant Performance and Meteorological Parameters

NASA Astrophysics Data System (ADS)

Sheng, Jie; Zhu, Qiaoming; Cao, Shijie; You, Yang

2017-05-01

This paper helps in study of the relationship between the photovoltaic power generation of large scale “fishing and PV complementary” grid-tied photovoltaic system and meteorological parameters, with multi-time scale power data from the photovoltaic power station and meteorological data over the same period of a whole year. The result indicates that, the PV power generation has the most significant correlation with global solar irradiation, followed by diurnal temperature range, sunshine hours, daily maximum temperature and daily average temperature. In different months, the maximum monthly average power generation appears in August, which related to the more global solar irradiation and longer sunshine hours in this month. However, the maximum daily average power generation appears in October, this is due to the drop in temperature brings about the improvement of the efficiency of PV panels. Through the contrast of monthly average performance ratio (PR) and monthly average temperature, it is shown that, the larger values of monthly average PR appears in April and October, while it is smaller in summer with higher temperature. The results concluded that temperature has a great influence on the performance ratio of large scale grid-tied PV power system, and it is important to adopt effective measures to decrease the temperature of PV plant properly.

Population dose commitments due to radioactive releases from nuclear power plant sites in 1987

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

Baker, D.A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1987. Fifty-year dose commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 70 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for reach of the sites is a histogram showing the fraction of the total population within 2 to 80 kmmore » around each site receiving various average dose commitments from the airborne pathways. The site average individual dose commitment from all pathways ranged from a low of 2 {times} 10{sup {minus}6} mrem to a high of 0.009 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. However, licensee calculation of doses to the maximally exposed individual at some sites indicated values of up to approximately 100 times average individual doses (on the order of a few millirem per year). 2 refs., 2 figs., 7 tabs.« less

Impacts of coal burning on ambient PM2.5 pollution in China

NASA Astrophysics Data System (ADS)

Ma, Qiao; Cai, Siyi; Wang, Shuxiao; Zhao, Bin; Martin, Randall V.; Brauer, Michael; Cohen, Aaron; Jiang, Jingkun; Zhou, Wei; Hao, Jiming; Frostad, Joseph; Forouzanfar, Mohammad H.; Burnett, Richard T.

2017-04-01

High concentration of fine particles (PM2.5), the primary concern about air quality in China, is believed to closely relate to China's large consumption of coal. In order to quantitatively identify the contributions of coal combustion in different sectors to ambient PM2. 5, we developed an emission inventory for the year 2013 using up-to-date information on energy consumption and emission controls, and we conducted standard and sensitivity simulations using the chemical transport model GEOS-Chem. According to the simulation, coal combustion contributes 22 µg m-3 (40 %) to the total PM2. 5 concentration at national level (averaged in 74 major cities) and up to 37 µg m-3 (50 %) in the Sichuan Basin. Among major coal-burning sectors, industrial coal burning is the dominant contributor, with a national average contribution of 10 µg m-3 (17 %), followed by coal combustion in power plants and the domestic sector. The national average contribution due to coal combustion is estimated to be 18 µg m-3 (46 %) in summer and 28 µg m-3 (35 %) in winter. While the contribution of domestic coal burning shows an obvious reduction from winter to summer, contributions of coal combustion in power plants and the industrial sector remain at relatively constant levels throughout the year.

National-level infrastructure and economic effects of switchgrass cofiring with coal in existing power plants for carbon mitigation.

PubMed

Morrow, William R; Griffin, W Michael; Matthews, H Scott

2008-05-15

We update a previously presented Linear Programming (LP) methodology for estimating state level costs for reducing CO2 emissions from existing coal-fired power plants by cofiring switchgrass, a biomass energy crop, and coal. This paper presents national level results of applying the methodology to the entire portion of the United States in which switchgrass could be grown without irrigation. We present incremental switchgrass and coal cofiring carbon cost of mitigation curves along with a presentation of regionally specific cofiring economics and policy issues. The results show that cofiring 189 million dry short tons of switchgrass with coal in the existing U.S. coal-fired electricity generation fleet can mitigate approximately 256 million short tons of carbon-dioxide (CO2) per year, representing a 9% reduction of 2005 electricity sector CO2 emissions. Total marginal costs, including capital, labor, feedstock, and transportation, range from $20 to $86/ton CO2 mitigated,with average costs ranging from $20 to $45/ton. If some existing power plants upgrade to boilers designed for combusting switchgrass, an additional 54 million tons of switchgrass can be cofired. In this case, total marginal costs range from $26 to $100/ton CO2 mitigated, with average costs ranging from $20 to $60/ton. Costs for states east of the Mississippi River are largely unaffected by boiler replacement; Atlantic seaboard states represent the lowest cofiring cost of carbon mitigation. The central plains states west of the Mississippi River are most affected by the boiler replacement option and, in general, go from one of the lowest cofiring cost of carbon mitigation regions to the highest. We explain the variation in transportation expenses and highlight regional cost of mitigation variations as transportation overwhelms other cofiring costs.

Analysis of economic determinants of fertility in Iran: a multilevel approach.

PubMed

Moeeni, Maryam; Pourreza, Abolghasem; Torabi, Fatemeh; Heydari, Hassan; Mahmoudi, Mahmood

2014-08-01

During the last three decades, the Total Fertility Rate (TFR) in Iran has fallen considerably; from 6.5 per woman in 1983 to 1.89 in 2010. This paper analyzes the extent to which economic determinants at the micro and macro levels are associated with the number of children in Iranian households. Household data from the 2010 Household Expenditure and Income Survey (HEIS) is linked to provincial data from the 2010 Iran Multiple-Indicator Demographic and Health Survey (IrMIDHS), the National Census of Population and Housing conducted in 1986, 1996, 2006 and 2011, and the 1985-2010 Iran statistical year books. Fertility is measured as the number of children in each household. A random intercept multilevel Poisson regression function is specified based on a collective model of intra-household bargaining power to investigate potential determinants of the number of children in Iranian households. Ceteris paribus (other things being equal), probability of having more children drops significantly as either real per capita educational expenditure or real total expenditure of each household increase. Both the low- and the high-income households show probabilities of having more children compared to the middle-income households. Living in provinces with either higher average amount of value added of manufacturing establishments or lower average rate of house rent is associated to higher probability of having larger number of children. Higher levels of gender gap indices, resulting in household's wife's limited power over household decision-making, positively affect the probability of having more children. Economic determinants at the micro and macro levels, distribution of intra-household bargaining power between spouses and demographic covariates determined fertility behavior of Iranian households.

Analysis of economic determinants of fertility in Iran: a multilevel approach

PubMed Central

Moeeni, Maryam; Pourreza, Abolghasem; Torabi, Fatemeh; Heydari, Hassan; Mahmoudi, Mahmood

2014-01-01

Background: During the last three decades, the Total Fertility Rate (TFR) in Iran has fallen considerably; from 6.5 per woman in 1983 to 1.89 in 2010. This paper analyzes the extent to which economic determinants at the micro and macro levels are associated with the number of children in Iranian households. Methods: Household data from the 2010 Household Expenditure and Income Survey (HEIS) is linked to provincial data from the 2010 Iran Multiple-Indicator Demographic and Health Survey (IrMIDHS), the National Census of Population and Housing conducted in 1986, 1996, 2006 and 2011, and the 1985–2010 Iran statistical year books. Fertility is measured as the number of children in each household. A random intercept multilevel Poisson regression function is specified based on a collective model of intra-household bargaining power to investigate potential determinants of the number of children in Iranian households. Results: Ceteris paribus (other things being equal), probability of having more children drops significantly as either real per capita educational expenditure or real total expenditure of each household increase. Both the low- and the high-income households show probabilities of having more children compared to the middle-income households. Living in provinces with either higher average amount of value added of manufacturing establishments or lower average rate of house rent is associated to higher probability of having larger number of children. Higher levels of gender gap indices, resulting in household’s wife’s limited power over household decision-making, positively affect the probability of having more children. Conclusion: Economic determinants at the micro and macro levels, distribution of intra-household bargaining power between spouses and demographic covariates determined fertility behavior of Iranian households. PMID:25197678

47 CFR 15.403 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... power control level. Power must be summed across all antennas and antenna elements. The average must not... symbols, during which the average symbol envelope power is constant. (q) RLAN. Radio Local Area Network. (r) Transmit Power Control (TPC). A feature that enables a U-NII device to dynamically switch between...

Method and Apparatus for Monitoring of Daily Activity in Terms of Ground Reaction Forces

NASA Technical Reports Server (NTRS)

Whalen, Robert T. (Inventor); Breit, Gregory A. (Inventor)

2001-01-01

A device to record and analyze habitual daily activity in terms of the history of gait-related musculoskeletal loading is disclosed. The device consists of a pressure-sensing insole placed into the shoe or embedded in a shoe sole, which detects contact of the foot with the ground. The sensor is coupled to a portable battery-powered digital data logger clipped to the shoe or worn around the ankle or waist. During the course of normal daily activity, the system maintains a record of time-of-occurrence of all non-spurious foot-down and lift-off events. Off line, these data are filtered and converted to a history of foot-ground contact times, from which measures of cumulative musculoskeletal loading, average walking- and running-specific gait speed, total time spent walking and running, total number of walking steps and running steps, and total gait-related energy expenditure are estimated from empirical regressions of various gait parameters to the contact time reciprocal. Data are available as cumulative values or as daily averages by menu selection. The data provided by this device are useful for assessment of musculoskeletal and cardiovascular health and risk factors associated with habitual patterns of daily activity.

Heat flow from Io /JI/

NASA Technical Reports Server (NTRS)

Matson, D. L.; Ransford, G. A.; Johnson, T. V.

1981-01-01

The existing ground-based measurements of Io's thermal emission at infrared wavelengths of 8.4, 10.6, and 21 microns have been reexamined. Present in these data is the signature of hot spots, presumably similar to the hot spots seen by the IRIS experiment on Voyager. It is possible to extract from these data the total amount of power radiated. Since the hot spots are believed to be a result of deep-seated activity in Io and since the remainder of Io's surface is an extraordinarily poor thermal conductor, the power radiated by the hot spots is essentially the total heat flow. The analysis yields a heat flow of 2 + or - 1 W/sq m. This value is tremendously large in comparison to the average heat flow of the earth (0.06 W/sq m) and the moon (0.02 W/sq m), but is characteristic of active geothermal areas on the earth. A heat flow this large requires that the interior of Io be at least partially molten on a global scale.

Relevance of Clean Coal Technology for India’s Energy Security: A Policy Perspective

NASA Astrophysics Data System (ADS)

Garg, Amit; Tiwari, Vineet; Vishwanathan, Saritha

2017-07-01

Climate change mitigation regimes are expected to impose constraints on the future use of fossil fuels in order to reduce greenhouse gas (GHG) emissions. In 2015, 41% of total final energy consumption and 64% of power generation in India came from coal. Although almost a sixth of the total coal based thermal power generation is now super critical pulverized coal technology, the average CO2 emissions from the Indian power sector are 0.82 kg-CO2/kWh, mainly driven by coal. India has large domestic coal reserves which give it adequate energy security. There is a need to find options that allow the continued use of coal while considering the need for GHG mitigation. This paper explores options of linking GHG emission mitigation and energy security from 2000 to 2050 using the AIM/Enduse model under Business-as-Usual scenario. Our simulation analysis suggests that advanced clean coal technologies options could provide promising solutions for reducing CO2 emissions by improving energy efficiencies. This paper concludes that integrating climate change security and energy security for India is possible with a large scale deployment of advanced coal combustion technologies in Indian energy systems along with other measures.

Energy Budgets of the Giant Planets and Titan

NASA Technical Reports Server (NTRS)

Liming, Li; Smith, Mark A.; Conrath, Barney J.; Conrath, Peter J.; Simon-Miller, Amy A.; Baines, Kevin H.; West, Robert A.; Achterberg, Richard K.; Orton, Glenn S.; Santiago, Perez-Hoyos;

Design and Development of the Space Technology 5 (ST5) Solar Arrays

NASA Technical Reports Server (NTRS)

Lyons, John; Fatemi, Navid; Gamica, Robert; Sharma, Surya; Senft, Donna; Maybery, Clay

2005-01-01

The National Aeronautics and Space Administration's (NASA's) Space Technology 5 (ST5) is designed to flight-test the concept of miniaturized 'small size" satellites and innovative technologies in Earth's magnetosphere. Three satellites will map the intensity and direction of the magnetic fields within the inner magnetosphere. Due to the small area available for the solar arrays, and to meet the mission power requirements, very high-efficiency multijunction solar cells were selected to power the spacecraft built by NASA Goddard Space Flight Center (GSFC). This was done in partnership with the Air Force Research Lab (AFRL) through the Dual-Use Science and Technology (DUS&T) program. Emcore's InGaP/lnGaAs/Ge Advanced triple-junction (ATJ) solar cells, exhibiting an average air mass zero (AMO) efficiency of 28.0% (one-sun, 28 C), were used to populate the arrays. Each spacecraft employs 8 identical solar panels (total area of about 0.3 square meters), with 15 large-area solar cells per panel. The requirement for power is to support on-orbit average load of 13.5 W at 8.4 V, with plus or minus 5% off pointing. The details of the solar array design, development and qualification considerations, as well as ground electrical performance & shadowing analysis results are presented.

Apertured averaged scintillation of fully and partially coherent Gaussian, annular Gaussian, flat toped and dark hollow beams

NASA Astrophysics Data System (ADS)

Eyyuboğlu, Halil T.

2015-03-01

Apertured averaged scintillation requires the evaluation of rather complicated irradiance covariance function. Here we develop a much simpler numerical method based on our earlier introduced semi-analytic approach. Using this method, we calculate aperture averaged scintillation of fully and partially coherent Gaussian, annular Gaussian flat topped and dark hollow beams. For comparison, the principles of equal source beam power and normalizing the aperture averaged scintillation with respect to received power are applied. Our results indicate that for fully coherent beams, upon adjusting the aperture sizes to capture 10 and 20% of the equal source power, Gaussian beam needs the largest aperture opening, yielding the lowest aperture average scintillation, whilst the opposite occurs for annular Gaussian and dark hollow beams. When assessed on the basis of received power normalized aperture averaged scintillation, fixed propagation distance and aperture size, annular Gaussian and dark hollow beams seem to have the lowest scintillation. Just like the case of point-like scintillation, partially coherent beams will offer less aperture averaged scintillation in comparison to fully coherent beams. But this performance improvement relies on larger aperture openings. Upon normalizing the aperture averaged scintillation with respect to received power, fully coherent beams become more advantageous than partially coherent ones.

53 W average power few-cycle fiber laser system generating soft x rays up to the water window.

PubMed

Rothhardt, Jan; Hädrich, Steffen; Klenke, Arno; Demmler, Stefan; Hoffmann, Armin; Gotschall, Thomas; Eidam, Tino; Krebs, Manuel; Limpert, Jens; Tünnermann, Andreas

2014-09-01

We report on a few-cycle laser system delivering sub-8-fs pulses with 353 μJ pulse energy and 25 GW of peak power at up to 150 kHz repetition rate. The corresponding average output power is as high as 53 W, which represents the highest average power obtained from any few-cycle laser architecture so far. The combination of both high average and high peak power provides unique opportunities for applications. We demonstrate high harmonic generation up to the water window and record-high photon flux in the soft x-ray spectral region. This tabletop source of high-photon flux soft x rays will, for example, enable coherent diffractive imaging with sub-10-nm resolution in the near future.

Autonomous exoskeleton reduces metabolic cost of walking.

PubMed

Mooney, Luke M; Rouse, Elliott J; Herr, Hugh M

2014-01-01

We developed an autonomous powered leg exoskeleton capable of providing large amounts of positive mechanical power to the wearer during powered plantarflexion phase of walking. The autonomous exoskeleton consisted of a winch actuator fasted to the shin which pulled on fiberglass struts attached to a boot. The fiberglass struts formed a rigid extension of the foot when the proximal end of the strut was pulled in forward by the winch actuator. This lightweight, geometric transmission allowed the electric winch actuator to efficiently produce biological levels of power at the ankle joint. The exoskeleton was powered and controlled by lithium polymer batteries and motor controller worn around the waist. Preliminary testing on two subjects walking at 1.4 m/s resulted in the exoskeleton reducing the metabolic cost of walking by 6-11% as compared to not wearing the device. The exoskeleton provided a peak mechanical power of over 180 W at each ankle (mean standard ± deviation) and an average positive mechanical power of 27 ± 1 W total to both ankles, while electrically using 75-89 W of electricity. The batteries (800 g) used in this experiment are estimated to be capable of providing this level of assistance for up to 7 km of walking.

Thermal Investigation of Interaction between High-power CW-laser Radiation and a Water-jet

NASA Astrophysics Data System (ADS)

Brecher, Christian; Janssen, Henning; Eckert, Markus; Schmidt, Florian

The technology of a water guided laser beam has been industrially established for micro machining. Pulsed laser radiation is guided via a water jet (diameter: 25-250 μm) using total internal reflection. Due to the cylindrical jet shape the depth of field increases to above 50 mm, enabling parallel kerfs compared to conventional laser systems. However higher material thicknesses and macro geometries cannot be machined economically viable due to low average laser powers. Fraunhofer IPT has successfully combined a high-power continuous-wave (CW) fiber laser (6 kW) and water jet technology. The main challenge of guiding high-power laser radiation in water is the energy transferred to the jet by absorption, decreasing its stability. A model of laser water interaction in the water jet has been developed and validated experimentally. Based on the results an upscaling of system technology to 30 kW is discussed, enabling a high potential in cutting challenging materials at high qualities and high speeds.

Muscle anatomy and dynamic muscle function in osteogenesis imperfecta type I.

PubMed

Veilleux, Louis-Nicolas; Lemay, Martin; Pouliot-Laforte, Annie; Cheung, Moira S; Glorieux, Francis H; Rauch, Frank

2014-02-01

Results of previous studies suggested that children and adolescents with osteogenesis imperfecta (OI) type I have a muscle force deficit. However, muscle function has only been assessed by static isometric force tests and not in more natural conditions such as dynamic force and power tests. The purpose of this study was to assess lower extremity dynamic muscle function and muscle anatomy in OI type I. The study was performed in the outpatient department of a pediatric orthopedic hospital. A total of 54 individuals with OI type I (6-21 years; 20 male) and 54 age- and sex-matched controls took part in this study. Calf muscle cross-sectional area and density were measured by peripheral quantitative computed tomography. Lower extremity muscle function (peak force per body weight and peak power per body mass) was measured by jumping mechanography through 5 tests: multiple two-legged hopping, multiple one-legged hopping, single two-legged jump, chair-rise test, and heel-rise test. Compared with age- and sex-matched controls, patients with OI type I had smaller muscle size (P = .04) but normal muscle density (P = .21). They also had lower average peak force and lower specific force (peak force/muscle cross-sectional area; all P < .008). Average peak power was lower in patients with OI type I but not significantly so (all P > .054). Children and adolescents with OI type I have, on average, a significant force deficit in the lower limb as measured by dynamic force tests. Nonetheless, these data also show that OI type I is compatible with normal muscle performance in some individuals.

Development of a 33 kV, 20 A long pulse converter modulator for high average power klystron

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

Reghu, T.; Mandloi, V.; Shrivastava, Purushottam

Research, design, and development of high average power, long pulse modulators for the proposed Indian Spallation Neutron Source are underway at Raja Ramanna Centre for Advanced Technology. With this objective, a prototype of long pulse modulator capable of delivering 33 kV, 20 A at 5 Hz repetition rate has been designed and developed. Three Insulated Gate Bipolar Transistors (IGBT) based switching modules driving high frequency, high voltage transformers have been used to generate high voltage output. The IGBT based switching modules are shifted in phase by 120° with respect to each other. The switching frequency is 25 kHz. Pulses ofmore » 1.6 ms pulse width, 80 μs rise time, and 70 μs fall time have been achieved at the modulator output. A droop of ±0.6% is achieved using a simple segmented digital droop correction technique. The total fault energy transferred to the load during fault has been measured by conducting wire burn tests and is found to be within 3.5 J.« less

Development of a 33 kV, 20 A long pulse converter modulator for high average power klystron

NASA Astrophysics Data System (ADS)

Reghu, T.; Mandloi, V.; Shrivastava, Purushottam

2014-05-01

Research, design, and development of high average power, long pulse modulators for the proposed Indian Spallation Neutron Source are underway at Raja Ramanna Centre for Advanced Technology. With this objective, a prototype of long pulse modulator capable of delivering 33 kV, 20 A at 5 Hz repetition rate has been designed and developed. Three Insulated Gate Bipolar Transistors (IGBT) based switching modules driving high frequency, high voltage transformers have been used to generate high voltage output. The IGBT based switching modules are shifted in phase by 120° with respect to each other. The switching frequency is 25 kHz. Pulses of 1.6 ms pulse width, 80 μs rise time, and 70 μs fall time have been achieved at the modulator output. A droop of ±0.6% is achieved using a simple segmented digital droop correction technique. The total fault energy transferred to the load during fault has been measured by conducting wire burn tests and is found to be within 3.5 J.

Chromosomal Aberrations in Wild Mice Captured in Areas Differentially Contaminated by the Fukushima Dai-Ichi Nuclear Power Plant Accident.

PubMed

Kubota, Yoshihisa; Tsuji, Hideo; Kawagoshi, Taiki; Shiomi, Naoko; Takahashi, Hiroyuki; Watanabe, Yoshito; Fuma, Shoichi; Doi, Kazutaka; Kawaguchi, Isao; Aoki, Masanari; Kubota, Masahide; Furuhata, Yoshiaki; Shigemura, Yusaku; Mizoguchi, Masahiko; Yamada, Fumio; Tomozawa, Morihiko; Sakamoto, Shinsuke H; Yoshida, Satoshi

2015-08-18

Following the Fukushima Dai-ichi Nuclear Power Plant accident, radiation effects on nonhuman biota in the contaminated areas have been a great concern. The induction of chromosomal aberrations in splenic lymphocytes of small Japanese field mice (Apodemus argenteus) and house mice (Mus musculus) inhabiting Fukushima Prefecture was investigated. In mice inhabiting the slightly contaminated area, the average frequency of dicentric chromosomes was similar to that seen in mice inhabiting a noncontaminated control area. In contrast, mice inhabiting the moderately and heavily contaminated areas showed a significant increase in the average frequencies of dicentric chromosomes. Total absorbed dose rate was estimated to be approximately 1 mGy d(-1) and 3 mGy d(-1) in the moderately and heavily contaminated areas, respectively. Chromosomal aberrations tended to roughly increase with dose rate. Although theoretically, the frequency of chromosomal aberrations was considered proportional to the absorbed dose, chromosomal aberrations in old mice (estimated median age 300 days) did not increase with radiation dose at the same rate as that observed in young mice (estimated median age 105 days).

Retinal specializations and visual ecology in an animal with an extremely elaborate pupil shape: The Little skate Leucoraja (Raja) erinacea Mitchell, 1825.

PubMed

Jinson, S Terrell; Liebich, Jan; Senft, Stephen L; Mäthger, Lydia M

2018-05-14

Investigating retinal specializations offers insights into eye functionality. Using retinal wholemount techniques, we investigated the distribution of retinal ganglion cells in the Little skate Leucoraja erinacea by (1) dye-backfilling into the optic nerve prior to retinal wholemounting; (2) Nissl-staining of retinal wholemounts. Retinas were examined for regional specializations (higher numbers) of ganglion cells that would indicate higher visual acuity in those areas. Total ganglion cell number were low compared to other elasmobranchs (backfilled: average 49,713 total ganglion cells, average peak cell density 1,315 ganglion cells mm -2 ; Nissl-stained: average 47,791 total ganglion cells, average peak cell density 1,319 ganglion cells mm -2 ). Ganglion cells fit into three size categories: small (5-20µm); medium (20-30µm); large: (≥ 30µm), and they were not homogeneously distributed across the retina. There was a dorsally located horizontal visual streak with increased ganglion cell density; additionally, there were approximately 3 local maxima in ganglion cell distribution (potential areae centrales) within this streak in which densities were highest. Using computerized tomography (CT) and micro-CT, geometrical dimensions of the eye were obtained. Combined with ganglion cell distributions, spatial resolving power was determined to be between 1.21 to 1.37 cycles per degree. Additionally, photoreceptor sizes across different retinal areas varied; photoreceptors were longest within the horizontal visual streak. Variations in the locations of retinal specializations appear to be related to the animal's anatomy: shape of the head and eyes, position of eyes, location of tapetum, and shape of pupil, as well as the visual demands associated with lifestyle and habitat type. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

High-Average-Power Diffraction Pulse-Compression Gratings Enabling Next-Generation Ultrafast Laser Systems

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

Alessi, D.

Pulse compressors for ultrafast lasers have been identified as a technology gap in the push towards high peak power systems with high average powers for industrial and scientific applications. Gratings for ultrashort (sub-150fs) pulse compressors are metallic and can absorb a significant percentage of laser energy resulting in up to 40% loss as well as thermal issues which degrade on-target performance. We have developed a next generation gold grating technology which we have scaled to the petawatt-size. This resulted in improvements in efficiency, uniformity and processing as compared to previous substrate etched gratings for high average power. This new designmore » has a deposited dielectric material for the grating ridge rather than etching directly into the glass substrate. It has been observed that average powers as low as 1W in a compressor can cause distortions in the on-target beam. We have developed and tested a method of actively cooling diffraction gratings which, in the case of gold gratings, can support a petawatt peak power laser with up to 600W average power. We demonstrated thermo-mechanical modeling of a grating in its use environment and benchmarked with experimental measurement. Multilayer dielectric (MLD) gratings are not yet used for these high peak power, ultrashort pulse durations due to their design challenges. We have designed and fabricated broad bandwidth, low dispersion MLD gratings suitable for delivering 30 fs pulses at high average power. This new grating design requires the use of a novel Out Of Plane (OOP) compressor, which we have modeled, designed, built and tested. This prototype compressor yielded a transmission of 90% for a pulse with 45 nm bandwidth, and free of spatial and angular chirp. In order to evaluate gratings and compressors built in this project we have commissioned a joule-class ultrafast Ti:Sapphire laser system. Combining the grating cooling and MLD technologies developed here could enable petawatt laser systems to operate at 50kW average power.« less

Single Piezo-Actuator Rotary-Hammering (SPaRH) Drill

NASA Technical Reports Server (NTRS)

Sherrit, Stewart (Inventor); Bao, Xiaoqi (Inventor); Badescu, Mircea (Inventor); Bar-Cohen, Yoseph (Inventor)

2014-01-01

A Single Piezo-Actuator Rotary-Hammering (SPaRH) Drill includes a horn actuator having high power piezoelectric materials and a flexure pre-stress to increase the actuators effectiveness. The drill is a low mass, low power, compact coring drill measuring 20-cm high by 7-cm diameter and having a total weight of 2 kg including drive electronics. Using an average power of 50-Watts, the drill basalt is expected to cut basalt at a rate of 0.2 cm/min down to depth of 10-cm and create cuttings and an intact core. The drill is expected to operate under different environments including Martian ambient (6 Torr and down to -50 degree C), and liquid nitrogen temperatures (77 K) and low pressure (<<1 Torr) to simulate lunar polar and Europa conditions. Materials expected to be sampled include Kaolinite, Saddleback Basalt, Limestone, Volcanic Breccia, Siltstone, ice, permafrost and layered rocks with different hardness.

The global star formation law of galaxies revisited in the radio continuum

NASA Astrophysics Data System (ADS)

Liu, LiJie; Gao, Yu

2012-02-01

We study the global star formation law, the relation between the gas and star formation rate (SFR) in a sample of 130 local galaxies with infrared (IR) luminosities spanning over three orders of magnitude (109-1012 L⊙), which includes 91 normal spiral galaxies and 39 (ultra)luminous IR galaxies [(U)LIRGs]. We derive their total (atomic and molecular) gas and dense molecular gas masses using newly available HI, CO and HCN data from the literature. The SFR of galaxies is determined from total IR (8-1000 μm) and 1.4 GHz radio continuum (RC) luminosities. The galaxy disk sizes are defined by the de-convolved elliptical Gaussian FWHM of the RC maps. We derive the galaxy disk-averaged SFRs and various gas surface densities, and investigate their relationships. We find that the galaxy disk-averaged surface density of dense molecular gas mass has the tightest correlation with that of SFR (scatter ˜0.26 dex), and is linear in log-log space (power-law slope of N=1.03±0.02) across the full galaxy sample. The correlation between the total gas and SFR surface densities for the full sample has a somewhat larger scatter (˜0.48 dex), and is best fit by a power-law with slope 1.45±0.02. However, the slope changes from ˜1 when only normal spirals are considered, to ˜1.5 when more and more (U)LIRGs are included in the fitting. When different CO-to-H2 conversion factors are used to infer molecular gas masses for normal galaxies and (U)LIRGs, the bi-modal relations claimed recently in CO observations of high-redshift galaxies appear to also exist in local populations of star-forming galaxies.

Physicochemical and Antioxidant Properties of Honeys from the Sundarbans Mangrove Forest of Bangladesh

PubMed Central

Islam, M Rabiul; Pervin, Tahmina; Hossain, Hemayet; Saha, Badhan; Hossain, Sheikh Julfikar

2017-01-01

This study evaluated the physicochemical, nutritional, antioxidant, and phenolic properties of ten honey samples from the Sundarbans mangrove forest, Bangladesh. The average pH, electrical conductivity, total dissolved solid, ash, moisture, hydroxymethyl furfural, titrable acidity, and absorbance were 4.3, 0.38 mS/cm, 187.5 ppm, 0.14%, 17.88%, 4.4 mg/kg, 37.7 meq/kg, and 483 mAU, respectively. In the honeys, the average contents of Ca, Cu, Fe, K, Mg, Mn, and Na were 95.5, 0.19, 6.4, 302, 39.9, 3.4, and 597 ppm, respectively, whereas Cd, Cr, Pb, and Ni were not found. The average contents of total sugar, protein, lipid, vitamin C, polyphenols, flavonoids, and anthocyanins in the honeys were 69.3%, 0.8%, 0.29%, 107.3 mg/kg, 757.2 mg gallic acid equivalent/kg, 43.1 mg chatechin equivalent/kg, and 5.4 mg/kg, respectively. The honeys had strong 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity, reducing power and total antioxidant capacity. High-performance liquid chromatography analysis of the honey fractions revealed the quantification of six polyphenols namely, (+)-catechin, (−)-epicatechin, p-caumeric acid, syringic acid, trans-cinnamic acid, and vanillic acid at 194.98, 330.34, 74.64, 218.97, 49.55, and 118.84 mg/kg, respectively. Therefore, the honeys in the Sundarbans are of excellent quality and a prospective source of polyphenols, and antioxidants. PMID:29333387

Physicochemical and Antioxidant Properties of Honeys from the Sundarbans Mangrove Forest of Bangladesh.

PubMed

Islam, M Rabiul; Pervin, Tahmina; Hossain, Hemayet; Saha, Badhan; Hossain, Sheikh Julfikar

2017-12-01

This study evaluated the physicochemical, nutritional, antioxidant, and phenolic properties of ten honey samples from the Sundarbans mangrove forest, Bangladesh. The average pH, electrical conductivity, total dissolved solid, ash, moisture, hydroxymethyl furfural, titrable acidity, and absorbance were 4.3, 0.38 mS/cm, 187.5 ppm, 0.14%, 17.88%, 4.4 mg/kg, 37.7 meq/kg, and 483 mAU, respectively. In the honeys, the average contents of Ca, Cu, Fe, K, Mg, Mn, and Na were 95.5, 0.19, 6.4, 302, 39.9, 3.4, and 597 ppm, respectively, whereas Cd, Cr, Pb, and Ni were not found. The average contents of total sugar, protein, lipid, vitamin C, polyphenols, flavonoids, and anthocyanins in the honeys were 69.3%, 0.8%, 0.29%, 107.3 mg/kg, 757.2 mg gallic acid equivalent/kg, 43.1 mg chatechin equivalent/kg, and 5.4 mg/kg, respectively. The honeys had strong 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity, reducing power and total antioxidant capacity. High-performance liquid chromatography analysis of the honey fractions revealed the quantification of six polyphenols namely, (+)-catechin, (-)-epicatechin, p -caumeric acid, syringic acid, trans -cinnamic acid, and vanillic acid at 194.98, 330.34, 74.64, 218.97, 49.55, and 118.84 mg/kg, respectively. Therefore, the honeys in the Sundarbans are of excellent quality and a prospective source of polyphenols, and antioxidants.

Flex-gear electrical power transmission

NASA Technical Reports Server (NTRS)

Vranish, John; Peritt, Jonathan

1993-01-01

This study was conducted to develop an alternative way of transferring electricity across a continuously rotating joint, with little wear and the potential for low electrical noise. The problems with wires, slip rings, electromagnetic couplings, and recently invented roll-rings are discussed. Flex-gears, an improvement of roll-rings, are described. An entire class of flexgear devices is developed. Finally, the preferred flex-gear device is optimized for maximum electrical contact and analyzed for average mechanical power loss and maximum stress. For a device diameter of six inches, the preferred device is predicted to have a total electrical contact area of 0.066 square inches. In the preferred device, a small amount of internal sliding produces a 0.003 inch-pound torque that resists the motion of the device.

Investigation of superlattice device structures

NASA Technical Reports Server (NTRS)

Gergis, I. S.; Manasevit, H. M.; Lin, A. L.; Jones, A. B.

1985-01-01

This report describes the investigation of growth properties, and the structure of epitaxial multilayer Si(Si(1x)Ge(x)) films grown on bulk Silicon Substrates. It also describes the fabrication and characterization of MOSFET and MESFET devices made on these epitaxial films. Films were grown in a CVD reactor using hydrides of Si and Ge with H2 and He as carrier gases. Growth temperatures were between 900 C and 1050 C with most films grown at 1000 C. Layer thickness was between 300A and 2000A and total film thickness was between 0.25 micro m and 7 micro m. The Ge content (X) in the alloy layers was between .05 and 0.2. N-type multilayer films grown on (100) p-type Si showed Hall mobility in the range 1000 to 1500 sq cm/v for an average carrier concentration of approx. 10 to the 16th power/cu cm. This is up to 50% higher than the Hall mobility observed in epitaxial Si films grown under the same conditions and with the same average carrier concentration. The mobility enhancement occurred in films with average carrier concentration (n) from 0.7 x 10 to the 16th power to 2 x 10 to the 17th power/cu cm, and total film thickness greater than 1.0 micro m. No mobility enhancement was seen in n-type multilayer films grown on (111) Si or in p-type multilayer films. The structure of the films was investigated was using SEM, TEM, AES, SIMS, and X-ray double crystal diffraction techniques. The film composition profile (AES, SIMS) showed that the transition region between layers is of the order of about 100A. The TEM examination revealed a well defined layered structure with fairly sharp interfaces and good crystalline quality. It also showed that the first few layers of the film (closest to the substrate) are uneven, most probably due to the initial growth pattern of the epitaxial film where growth occurs first in isolated islands that eventually growth and coalesce. The X-ray diffraction measurement determined the elastic strain and strain relief in the alloy layers of the film and the elastic strain in the intervening Si layers.

Population dose commitments due to radioactive releases from nuclear power plant sites in 1980

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

Baker, D.A.; Peloquin, R.A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1980. In addition doses derived from the shutdown reactors at the Three Mile Island site were included. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each site is a histogram showingmore » the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways ranged from a high of 40 person-rem to a low of 0.02 person-rem with an arithmetic mean of 4 person-rem. The total population dose for all sites was estimated at 180 person-rem for the 96 million people considered at risk.« less

Population dose commitments due to radioactive releases from nuclear power plant sites in 1983

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

Baker, D.A.; Peloquin, R.A.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1983. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 52 sites. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km aroundmore » each site receiving various average dose commitments from the airborne pathways. The total dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 45 person-rem to a low of 0.002 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 3 person-rem. The total population dose for all sites was estimated at 170 person-rem for the 100 million people considered at risk.« less

Public Exposure from Indoor Radiofrequency Radiation in the City of Hebron, West Bank-Palestine.

PubMed

Lahham, Adnan; Sharabati, Afefeh; ALMasri, Hussien

2015-08-01

This work presents the results of measured indoor exposure levels to radiofrequency (RF) radiation emitting sources in one of the major cities in the West Bank-the city of Hebron. Investigated RF emitters include FM, TV broadcasting stations, mobile telephony base stations, cordless phones [Digital Enhanced Cordless Telecommunications (DECT)], and wireless local area networks (WLAN). Measurements of power density were conducted in 343 locations representing different site categories in the city. The maximum total power density found at any location was about 2.3 × 10 W m with a corresponding exposure quotient of about 0.01. This value is well below unity, indicating compliance with the guidelines of the International Commission on Non-ionizing Radiation Protection (ICNIRP). The average total exposure from all RF sources was 0.08 × 10 W m. The relative contributions from different sources to the total exposure in terms of exposure quotient were evaluated and found to be 46% from FM radio, 26% from GSM900, 15% from DECT phones, 9% from WLAN, 3% from unknown sources, and 1% from TV broadcasting. RF sources located outdoors contribute about 73% to the population exposure indoors.

2016 Wind Technologies Market Report

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

Wiser, Ryan H.; Bolinger, Mark

The U.S. Department of Energy (DOE)’s Wind Technologies Market Report provides an annual overview of trends in the U.S. wind power market. You can find the report, a presentation, and a data file on the Files tab, below. Additionally, several data visualizations are available in the Data Visualizations tab. Highlights of this year’s report include: -Wind power additions continued at a rapid clip in 2016: $13 billion was invested in new wind power plants in 2016. In 2016, wind energy contributed 5.6% of the nation’s electricity supply, more than 10% of total electricity generation in fourteen states, and 29% tomore » 37% in three of those states—Iowa, South Dakota, and Kansas. -Bigger turbines are enhancing wind project performance: Increased blade lengths, in particular, have dramatically increased wind project capacity factors, one measure of project performance. For example, the average 2016 capacity factor among projects built in 2014 and 2015 was 42.6%, compared to an average of 32.1% among projects built from 2004 to 2011 and 25.4% among projects built from 1998 to 2001. -Low wind turbine pricing continues to push down installed project costs: Wind turbine prices have fallen from their highs in 2008, to $800–$1,100/kW. Overall, the average installed cost of wind projects in 2016 was $1,590/kW, down $780/kW from the peak in 2009 and 2010. -Wind energy prices remain low: After topping out at nearly 7¢/kWh for power purchase agreements (PPAs) executed in 2009, the national average price of wind PPAs has dropped to around 2¢/kWh—though this nationwide average is dominated by projects that hail from the lowest-priced Interior region of the country (such as Texas, Iowa, Oklahoma). These prices, which are possible in part due to federal tax support, compare favorably to the projected future fuel costs of gas-fired generation. -The supply chain continued to adjust to swings in domestic demand for wind equipment: Wind sector employment reached a new high of more than 101,000 full-time workers at the end of 2016. For wind projects recently installed in the U.S., domestically manufactured content is highest for nacelle assembly (>90%), towers (65-80%), and blades and hubs (50-70%), but is much lower (<20%) for most components internal to the turbine. -Continued strong growth in wind capacity is anticipated in the near term: With federal tax incentives still available, though declining, various forecasts for the domestic market show expected wind power capacity additions averaging more than 9,000 MW/year from 2017 to 2020.« less

Power collection reduction by mirror surface nonflatness and tracking error for a central receiver solar power system.

PubMed

McFee, R H

1975-07-01

The effects of random waviness, curvature, and tracking error of plane-mirror heliostats in a rectangular array around a central-receiver solar power system are determined by subdividing each mirror into 484 elements, assuming the slope of each element to be representative of the surface slope average at its location, and summing the contributions of all elements and then of all mirrors in the array. Total received power and flux density distribution are computed for a given sun location and set of array parameter values. Effects of shading and blocking by adjacent mirrors are included in the calculation. Alt-azimuth mounting of the heliostats is assumed. Representative curves for two receiver diameters and two sun locations indicate a power loss of 20% for random waviness, curvature, and tracking error of 0.1 degrees rms, 0.002 m(-1), and 0.5 degrees , 3sigma, respectively, for an 18.2-m diam receiver and 0.3 degrees rms, 0.005 m(-1), and greater than 1 degrees , respectively, for a 30.4-m diam receiver.

Onshore Wind Farms: Value Creation for Stakeholders in Lithuania

NASA Astrophysics Data System (ADS)

Burinskienė, Marija; Rudzkis, Paulius; Kanopka, Adomas

With the costs of fossil fuel consistently rising worldwide over the last decade, the development of green technologies has become a major goal in many countries. Therefore the evaluation of wind power projects becomes a very important task. To estimate the value of the technologies based on renewable resources also means taking into consideration social, economic, environmental, and scientific value of such projects. This article deals with economic evaluation of electricity generation costs of onshore wind farms in Lithuania and the key factors that have influence on wind power projects and offer a better understanding of social-economic context behind wind power projects. To achieve these goals, this article makes use of empirical data of Lithuania's wind power farms as well as data about the investment environment of the country.Based on empirical data of wind power parks, the research investigates the average wind farm generation efficiency in Lithuania. Employing statistical methods the return on investments of wind farms in Lithuania is calculated. The value created for every party involved and the total value of the wind farm is estimated according to Stakeholder theory.

Applications of high average power nonlinear optics

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

Velsko, S.P.; Krupke, W.F.

1996-02-05

Nonlinear optical frequency convertors (harmonic generators and optical parametric oscillators are reviewed with an emphasis on high average power performance and limitations. NLO materials issues and NLO device designs are discussed in reference to several emerging scientific, military and industrial commercial applications requiring {approx} 100 watt average power level in the visible and infrared spectral regions. Research efforts required to enable practical {approx} 100 watt class NLO based laser systems are identified.

High average power pockels cell

DOEpatents

Daly, Thomas P.

1991-01-01

A high average power pockels cell is disclosed which reduces the effect of thermally induced strains in high average power laser technology. The pockels cell includes an elongated, substantially rectangular crystalline structure formed from a KDP-type material to eliminate shear strains. The X- and Y-axes are oriented substantially perpendicular to the edges of the crystal cross-section and to the C-axis direction of propagation to eliminate shear strains.

Effect of 655 nm laser different powers on dog sperm motility parameters

NASA Astrophysics Data System (ADS)

Corral-Baqués, M. I.; Rigau, T.; Rivera, M. M.; Rodríguez-Gil, J. E.; Rigau, J.

2006-04-01

Introduction: One of the most appreciated features of the sperm is its motility, which depends on a big energy consumption despite differences among species. Laser acts direct or indirectly on mitochondria increasing ATP production. Material and method: By means of a Computer Aided Sperm Analysis (CASA) we have studied the effects of a 655 nm continuous wave diode laser irradiation at different power outputs with a dose of 3.3418 J on sperm motility. After an eosine-nigrosine stain to establish its quality, the second fraction of fresh beagle dog sperm was divided into 5 groups, 1 control and four to be irradiated respectively with an average output power of 6.84 mW, 15.43 mW, 33.05 mW and 49.66 mW. At times 0 and 45 minutes from irradiation pictures were taken and analysed with the Sperm class Analyzer SCA2002 programme. The motility parameters of 4987 spermatozoa studied were: curvilinear velocity (VCL), progressive velocity (VSL), straightness (STR), wobble (WOB), average path velocity (VAP), linearity (LIN), mean amplitude of lateral head displacement (ALHmed), beat cross frequency (BCF) and the total motility (MT). At time 15 minutes after irradiation a hypoosmotic swelling test (HOST) was done. Results: Several motility parameters that affect the overall motile sperm subpopulation structure have been changed by different output powers of a 655 nm diode laser irradiation, and prevents the decrease of the sperm motility properties along time.

Physical fitness, injuries, and team performance in soccer.

PubMed

Arnason, Arni; Sigurdsson, Stefan B; Gudmundsson, Arni; Holme, Ingar; Engebretsen, Lars; Bahr, Roald

2004-02-01

To investigate the relationship between physical fitness and team success in soccer, and to test for differences in physical fitness between different player positions. Participants were 306 male soccer players from 17 teams in the two highest divisions in Iceland. Just before the start of the 1999 soccer season, the following variables were tested: height and weight, body composition, flexibility, leg extension power, jump height, and peak O2 uptake. Injuries and player participation in matches and training were recorded through the 4-month competitive season. Team average physical fitness was compared with team success (final league standing) using a linear regression model. Physical fitness was also compared between players in different playing positions. A significant relationship was found between team average jump height (countermovement jump and standing jump) and team success (P = 0.009 and P = 0.012, respectively). The same trend was also found for leg extension power (P = 0.097), body composition (% body fat, P = 0.07), and the total number of injury days per team (P = 0.09). Goalkeepers demonstrated different fitness characteristics from outfield players. They were taller and heavier, more flexible in hip extension and knee flexion, and had higher leg extension power and a lower peak O2 uptake. However, only minor differences were observed between defenders, midfield players, and attackers. Coaches and medical support teams should pay more attention to jump and power training, as well as preventive measures and adequate rehabilitation of previous injuries to increase team success.

Yb-fiber-pumped mid-infrared picosecond optical parametric oscillator tunable across 6.2-6.7 µm

NASA Astrophysics Data System (ADS)

Kumar, S. Chaitanya; Casals, J. Canals; Parsa, S.; Zawilski, K. T.; Schunemann, P. G.; Ebrahim-Zadeh, M.

2018-06-01

We report a high-average-power picosecond optical parametric oscillator (OPO) tunable in the mid-infrared (mid-IR) based on CdSiP2 synchronously pumped by an Yb-fiber laser at 80 MHz repetition rate. Successful operation of this high-repetition-rate singly-resonant picosecond OPO has been enabled by the improved CSP crystal quality over a long interaction length. The OPO can be tuned across 1264-1284 nm in the near-IR signal and 6205-6724 nm in the mid-IR idler by temperature tuning the CSP crystal over 39-134 °C. By deploying a 5% output coupler for the resonant signal, we have extracted up to 44 mW of average power in the near-IR and up to 95 mW of non-resonant idler power at 6205 nm at 6.3% total conversion efficiency, with > 50 mW over > 55% of the mid-IR tuning range. We have investigated temperature-tuning characteristics of the OPO and compared the data with the theoretical calculations using the recent Sellmeier and thermo-optic coefficients for CdSiP2. The signal pulses from the OPO exhibit a Gaussian pulse duration of 19 ps centered at 1284 nm. We have also studied the output power stability of the OPO, resulting in a passive stability better than 1.9% rms for the near-IR signal and 2.4% rms for the mid-IR idler, measured over > 17 h, with both beams in high spatial quality.

Experimental study on parasitic mode suppression using FeSiAl in relativistic klystron amplifier

NASA Astrophysics Data System (ADS)

Zhang, Zehai

2015-03-01

Experimental study of parasitic mode suppression using electromagnetic attenuate material FeSiAl in an S-band Relativistic Klystron Amplifier (RKA) is presented in this paper. The FeSiAl powder is coated and sintered onto the inner surface of a drift tube which locates between the input and the middle cavity of the RKA. Cold tests show that the attenuate rate of the tube against parasitic mode TE11 is about 50%. Experiments carried out on the Torch-01 accelerator present that the tube is effective in suppressing the parasitic mode. Two typical outputs are obtained. When the diode voltage is on a moderate level, the RKA operates well and the parasitic mode is totally suppressed. The pulse length of the High Power Microwave (HPM) almost equals the electron beam pulse length and the HPM average output power is about 300 MW, with a power efficiency of 10%. When the diode voltage is on a higher level, the output power and efficiency rise but the parasitic mode oscillation occurred and the pulse length is shortened. By contrast, the parasitic mode oscillation is too strong for the RKA to operate normally with un-sintered drift tube. The experimental study implies that FeSiAl is effective in suppressing the parasitic mode oscillation in a certain extent. However, total suppression needs a deeper attenuate rate and further investigation.

Experimental study on parasitic mode suppression using FeSiAl in Relativistic Klystron Amplifier.

PubMed

Zhang, Zehai

2015-03-01

Experimental study of parasitic mode suppression using electromagnetic attenuate material FeSiAl in an S-band Relativistic Klystron Amplifier (RKA) is presented in this paper. The FeSiAl powder is coated and sintered onto the inner surface of a drift tube which locates between the input and the middle cavity of the RKA. Cold tests show that the attenuate rate of the tube against parasitic mode TE11 is about 50%. Experiments carried out on the Torch-01 accelerator present that the tube is effective in suppressing the parasitic mode. Two typical outputs are obtained. When the diode voltage is on a moderate level, the RKA operates well and the parasitic mode is totally suppressed. The pulse length of the High Power Microwave (HPM) almost equals the electron beam pulse length and the HPM average output power is about 300 MW, with a power efficiency of 10%. When the diode voltage is on a higher level, the output power and efficiency rise but the parasitic mode oscillation occurred and the pulse length is shortened. By contrast, the parasitic mode oscillation is too strong for the RKA to operate normally with un-sintered drift tube. The experimental study implies that FeSiAl is effective in suppressing the parasitic mode oscillation in a certain extent. However, total suppression needs a deeper attenuate rate and further investigation.

Universities scale like cities.

PubMed

van Raan, Anthony F J

2013-01-01

Recent studies of urban scaling show that important socioeconomic city characteristics such as wealth and innovation capacity exhibit a nonlinear, particularly a power law scaling with population size. These nonlinear effects are common to all cities, with similar power law exponents. These findings mean that the larger the city, the more disproportionally they are places of wealth and innovation. Local properties of cities cause a deviation from the expected behavior as predicted by the power law scaling. In this paper we demonstrate that universities show a similar behavior as cities in the distribution of the 'gross university income' in terms of total number of citations over 'size' in terms of total number of publications. Moreover, the power law exponents for university scaling are comparable to those for urban scaling. We find that deviations from the expected behavior can indeed be explained by specific local properties of universities, particularly the field-specific composition of a university, and its quality in terms of field-normalized citation impact. By studying both the set of the 500 largest universities worldwide and a specific subset of these 500 universities--the top-100 European universities--we are also able to distinguish between properties of universities with as well as without selection of one specific local property, the quality of a university in terms of its average field-normalized citation impact. It also reveals an interesting observation concerning the working of a crucial property in networked systems, preferential attachment.

Movement Demands and Metabolic Power Comparisons Between Elite and Subelite Australian Footballers.

PubMed

Johnston, Richard J; Watsford, Mark L; Austin, Damien J; Pine, Matthew J; Spurrs, Robert W

2015-10-01

This study examined the differences in movement demands and metabolic power output of elite and subelite Australian football (AF) players and quantified the movement profiles of a subelite AF competition. Movement variables were collected from AF players using Global Positioning System devices over 2 AF League (elite) and North East Australian Football League (NEAFL, subelite) seasons. A total of 500 files were collected from 37 elite and subelite nomadic AF players. NEAFL players covered 13,547 m at an average speed of 124.5 m·min(-1). Elite players performed more high-speed running (5.7-6.3%) and high acceleration and deceleration efforts (1.9-14.7%, p ≤ 0.05). The elite players had a higher mean metabolic power output (3.2%) and time spent at the very high power zone (15.9%, p ≤ 0.05). In contrast, elite players recorded a lower total match duration than the subelite players (4%, p ≤ 0.05). The contrasting amount of high-intensity activities performed by the 2 groups demonstrates the need to alter the training programs of subelite players to ensure they are capable of meeting the demands of elite football. The differences in match duration suggest that reducing subelite players' match time through increasing their rotations would assist the replication of movement profiles of elite players.

Average focal length and power of a section of any defined surface.

PubMed

Kaye, Stephen B

2010-04-01

To provide a method to allow calculation of the average focal length and power of a lens through a specified meridian of any defined surface, not limited to the paraxial approximations. University of Liverpool, Liverpool, United Kingdom. Functions were derived to model back-vertex focal length and representative power through a meridian containing any defined surface. Average back-vertex focal length was based on the definition of the average of a function, using the angle of incidence as an independent variable. Univariate functions allowed determination of average focal length and power through a section of any defined or topographically measured surface of a known refractive index. These functions incorporated aberrations confined to the section. The proposed method closely approximates the average focal length, and by inference power, of a section (meridian) of a surface to a single or scalar value. It is not dependent on the paraxial and other nonconstant approximations and includes aberrations confined to that meridian. A generalization of this method to include all orthogonal and oblique meridians is needed before a comparison with measured wavefront values can be made. Copyright (c) 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Health service costs in Europe: cost and reimbursement of primary hip replacement in nine countries.

PubMed

Stargardt, Tom

2008-01-01

This paper assesses variations in the cost of primary hip replacement between and within nine member states of the European Union (EU). It also compares the cost of service with public-payer reimbursements. To do so, data on cost and reimbursement were surveyed at the micro-level in 42 hospitals in Denmark, England, France, Germany, Hungary, Italy, The Netherlands, Poland, and Spain. The total cost of treatment ranged from 1290 euros (Hungary) to 8739 euros (The Netherlands), with a mean cost of 5043 euros (STD +/- 2071 euros). The main cost drivers were found to be implants (34% of total cost on average) and ward costs (20.9% of total cost on average). A one-way random effects analysis of variance model indicated that 74.0% of variation was between and only 26% of variation was within countries. In a two-level random-intercept regression model, purchasing-power parities explained 79.4% of the explainable between-country variation, while the percentage of uncemented implants used and the number of beds explained 12.1 and 1.6% of explainable within-country variation, respectively. The large differences in cost and reimbursement between Poland, Hungary, and the other EU member states shows that primary total hip replacement is a highly relevant case for cross-border care. Copyright 2008 John Wiley & Sons, Ltd.

CO 2 is dominant greenhouse gas emitted from six hydropower reservoirs in southeastern United States during peak summer emissions

DOE PAGES

Bevelhimer, Mark S.; Stewart, Aurthur J.; Fortner, Allison M.; ...

2016-01-06

During August-September 2012, we sampled six hydropower reservoirs in southeastern United States. for CO 2 and CH 4 emissions via three pathways: diffusive emissions from water surface; ebullition in the water column; and losses from dam tailwaters during power generation. Average total emission rates of CO 2 for the six reservoirs ranged from 1,127 to 2,051 mg m -2 d -1, which is low to moderate compared to CO 2 emissions rates reported for tropical hydropower reservoirs and boreal ponds and lakes, and similar to rates reported for other temperate reservoirs. Similar average rates for CH 4 were also relativelymore » low, ranging from 5 to 83 mg m -2 d -1. On a whole-reservoir basis, total emissions of CO 2 ranged nearly 10-fold, from ~51,000 kg per day for Fontana to ~486,000 kg per day for Guntersville, and total emissions of CH 4 ranged nearly 20-fold, from ~5 kg per day for Fontana to ~83 kg per day for Allatoona. Emissions through the tailwater pathway varied among reservoirs, comprising from 20 to 50% of total CO 2 emissions and 0 to 90% of CH 4 emissions, depending on the reservoir. Furthermore, several explanatory factors related to reservoir morphology and water quality were considered for observed differences among reservoirs.« less

Dynamics Behaviors of Scale-Free Networks with Elastic Demand

NASA Astrophysics Data System (ADS)

Li, Yan-Lai; Sun, Hui-Jun; Wu, Jian-Jun

Many real-world networks, such as transportation networks and Internet, have the scale-free properties. It is important to study the bearing capacity of such networks. Considering the elastic demand condition, we analyze load distributions and bearing capacities with different parameters through artificially created scale-free networks. The simulation results show that the load distribution follows a power-law form, which means some ordered pairs, playing the dominant role in the transportation network, have higher demand than other pairs. We found that, with the decrease of perceptual error, the total and average ordered pair demand will decrease and then stay in a steady state. However, with the increase of the network size, the average demand of each ordered pair will decrease, which is particularly interesting for the network design problem.

High-average-power 2 μm few-cycle optical parametric chirped pulse amplifier at 100 kHz repetition rate.

PubMed

Shamir, Yariv; Rothhardt, Jan; Hädrich, Steffen; Demmler, Stefan; Tschernajew, Maxim; Limpert, Jens; Tünnermann, Andreas

2015-12-01

Sources of long wavelengths few-cycle high repetition rate pulses are becoming increasingly important for a plethora of applications, e.g., in high-field physics. Here, we report on the realization of a tunable optical parametric chirped pulse amplifier at 100 kHz repetition rate. At a central wavelength of 2 μm, the system delivered 33 fs pulses and a 6 W average power corresponding to 60 μJ pulse energy with gigawatt-level peak powers. Idler absorption and its crystal heating is experimentally investigated for a BBO. Strategies for further power scaling to several tens of watts of average power are discussed.

Pulse compression of a high-power thin disk laser using rod-type fiber amplifiers.

PubMed

Saraceno, C J; Heckl, O H; Baer, C R E; Südmeyer, T; Keller, U

2011-01-17

We report on two pulse compressors for a high-power thin disk laser oscillator using rod-type fiber amplifiers. Both systems are seeded by a standard SESAM modelocked thin disk laser that delivers 16 W of average power at a repetition rate of 10.6 MHz with a pulse energy of 1.5 μJ and a pulse duration of 1 ps. We discuss two results with different fiber parameters with different trade-offs in pulse duration, average power, damage and complexity. The first amplifier setup consists of a Yb-doped fiber amplifier with a 2200 μm2 core area and a length of 55 cm, resulting in a compressed average power of 55 W with 98-fs pulses at a repetition rate of 10.6 MHz. The second system uses a shorter 36-cm fiber with a larger core area of 4500 μm2. In a stretcher-free configuration we obtained 34 W of compressed average power and 65-fs pulses. In both cases peak powers of > 30 MW were demonstrated at several μJ pulse energies. The power scaling limitations due to damage and self-focusing are discussed.

18 CFR 301.7 - Average System Cost methodology functionalization.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Average System Cost methodology functionalization. 301.7 Section 301.7 Conservation of Power and Water Resources FEDERAL ENERGY... ACT § 301.7 Average System Cost methodology functionalization. (a) Functionalization of each Account...

18 CFR 301.7 - Average System Cost methodology functionalization.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Average System Cost methodology functionalization. 301.7 Section 301.7 Conservation of Power and Water Resources FEDERAL ENERGY... ACT § 301.7 Average System Cost methodology functionalization. (a) Functionalization of each Account...

18 CFR 301.7 - Average System Cost methodology functionalization.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Average System Cost methodology functionalization. 301.7 Section 301.7 Conservation of Power and Water Resources FEDERAL ENERGY... ACT § 301.7 Average System Cost methodology functionalization. (a) Functionalization of each Account...

18 CFR 301.7 - Average System Cost methodology functionalization.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Average System Cost methodology functionalization. 301.7 Section 301.7 Conservation of Power and Water Resources FEDERAL ENERGY... ACT § 301.7 Average System Cost methodology functionalization. (a) Functionalization of each Account...

Computationally Efficient Resampling of Nonuniform Oversampled SAR Data

DTIC Science & Technology

2010-05-01

noncoherently . The resample data is calculated using both a simple average and a weighted average of the demodulated data. The average nonuniform...trials with randomly varying accelerations. The results are shown in Fig. 5 for the noncoherent power difference and Fig. 6 for and coherent power...simple average. Figure 5. Noncoherent difference between SAR imagery generated with uniform sampling and nonuniform sampling that was resampled

Natural radionuclide emission from coal-fired power plants in the southwestern of Turkey and the population exposure to external radiation in their vicinity.

PubMed

Gür, Filiz; Yaprak, Günseli

2010-12-01

To evaluate the effect of radionuclide emission on the environment from Yatagan, Yenikoy and Kemerkoy coal-fired power plants which are located in southwestern Anatolia of Turkey, the concentrations of natural radionuclides such as (226)Ra, (232)Th and (40)K in coal, bottom ash and fly ash samples, have been measured, as well as the concentration of the same radionuclides in surface soils. The dose rate arises from the total radioactivity content of soil that the people living by the power plants are exposed to be assessed additionally. The average activity concentrations of (226)Ra for Yatagan CPP is 80 ± 22 Bq kg(-1) ranging from 56 to 131 Bq kg(-1), for Yenikoy CPP is 138 ± 20 Bq kg(-1) ranging from 115 to 189 Bq kg(-1), for Kemerkoy CPP is 238 ± 80 Bq kg(-1) ranging from 134 to 356 Bq kg(-1) in coal; average activity concentrations of (226)Ra in fly ash and in bottom ash for above-mentioned power plants are 334 ± 60 Bq kg(-1) ranging from 291 to 481 Bq kg(-1), 461 ± 33 Bq kg(-1) ranging from 398 to 511 Bq kg(-1), 815 ± 254 Bq kg(-1) ranging from 316 to 1260 Bq kg(-1), 276 ± 51 Bq kg(-1) ranging from 222 to 349 Bq kg(-1), 285 ± 69 Bq kg(-1) ranging from 213 to 409 Bq kg(-1), 743 ± 234 Bq kg(-1) ranging from 366 to 1098 Bq kg(-1), respectively. The radionuclides activity concentrations of surface soil in the vicinity of coal-fired power plants are 32 ± 9 Bq kg(-1) (18-53 Bq kg(-1)) for (226)Ra, 37 ± 16 Bq kg(-1) (17-89 Bq kg(-1)) for (232)Th, 455 ± 165 Bq kg(-1) (203-794 Bq kg(-1)) for (40)K relevant to Yatagan CPP; 42 ± 30 Bq kg(-1) (9-168 Bq kg(-1)) for (226)Ra, 32 ± 14 Bq kg(-1) (6-74 Bq kg(-1)) for (232)Th, 365 ± 151 Bq kg(-1) (117-937 Bq kg(-1)) for (40)K relevant to Yenikoy and Kemerkoy CPP. As a result, average dose rates in the vicinity of coal-fired power plants have been calculated to be 56 ± 16 nGy h(-1) ranging from 30 to 100 nGy h(-1) for Yatagan CPP, 54 ± 22 nGy h(-1) ranging from 15 to 126 nGy h(-1) for Yenikoy and Kemerkoy CPP. To sum up, the natural radionuclide activity concentrations of burnt coal and ashes thrown out from these three power plants are quite high relative to the world average UNSCEAR[1] data. In addition, the average (226)Ra, (232)Th and (40)K activity concentration values of surface soil samples and the calculated gamma dose rates in the vicinity of power plants were located within the worldwide intervals reported by UNSCEAR,[30] with some local differences.

Electricity savings potentials in the residential sector of Bahrain

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

Akbari, H.; Morsy, M.G.; Al-Baharna, N.S.

1996-08-01

Electricity is the major fuel (over 99%) used in the residential, commercial, and industrial sectors in Bahrain. In 1992, the total annual electricity consumption in Bahrain was 3.45 terawatt-hours (TWh), of which 1.95 TWh (56%) was used in the residential sector, 0.89 TWh (26%) in the commercial sector, and 0.59 TWh (17%) in the industrial sector. Agricultural energy consumption was 0.02 TWh (less than 1%) of the total energy use. In Bahrain, most residences are air conditioned with window units. The air-conditioning electricity use is at least 50% of total annual residential use. The contribution of residential AC to themore » peak power consumption is even more significant, approaching 80% of residential peak power demand. Air-conditioning electricity use in the commercial sector is also significant, about 45% of the annual use and over 60% of peak power demand. This paper presents a cost/benefit analysis of energy-efficient technologies in the residential sector. Technologies studied include: energy-efficient air conditioners, insulating houses, improved infiltration, increasing thermostat settings, efficient refrigerators and freezers, efficient water heaters, efficient clothes washers, and compact fluorescent lights. We conservatively estimate a 32% savings in residential electricity use at an average cost of about 4 fils per kWh. (The subsidized cost of residential electricity is about 12 fils per kWh. 1000 fils = 1 Bahrain Dinar = US$ 2.67). We also discuss major policy options needed for implementation of energy-efficiency technologies.« less

Water use in Kentucky, 1985

USGS Publications Warehouse

Sholar, C.J.; Lee, V.D.

1988-01-01

Water use information for 1985 was collected and reported by county for eight major categories of use. Seven of the categories were offstream uses, which included (1) public supply , (2) commercial, (3) domestic, (4) industrial, (5) mining, (6) thermoelectric, and (7) agricultural uses. The agricultural uses category was separated into irrigation and livestock water use. Instream water-use data also were collected for hydroelectric power generation. Water use in Kentucky was estimated to average 4,200 million gallons per day (M gal/d) during 1985 for all offstream uses. About 95% of this amount was from surface water sources, and about 5% was from groundwater sources. Per capita use for all offstream uses was about 1,100 gal/day. About 260 M gal/d was consumed (not returned to the surface--or groundwater system). Instream water use for hydroelectric power generation was estimated to be 91,000 M gal/d. Almost 97% of the offstream water withdrawals in 1985 were withdrawn for thermoelectric, public supply, and industrial use. Cooling water used in the production of thermoelectric power accounted for about 81% of the total offstream water use in 1985. Water withdrawn for public supplies was the second largest offstream use at about 10 % of the total, and industrial water use was almost 6%. Thermoelectric, domestic, and livestock uses accounted for almost 90% of the consumptive use in 1985. Consumptive use in the thermoelectric category was almost one-half of the total amount consumed in the State for all uses. (USGS)

Simple, Defensible Sample Sizes Based on Cost Efficiency

PubMed Central

Bacchetti, Peter; McCulloch, Charles E.; Segal, Mark R.

2009-01-01

Summary The conventional approach of choosing sample size to provide 80% or greater power ignores the cost implications of different sample size choices. Costs, however, are often impossible for investigators and funders to ignore in actual practice. Here, we propose and justify a new approach for choosing sample size based on cost efficiency, the ratio of a study’s projected scientific and/or practical value to its total cost. By showing that a study’s projected value exhibits diminishing marginal returns as a function of increasing sample size for a wide variety of definitions of study value, we are able to develop two simple choices that can be defended as more cost efficient than any larger sample size. The first is to choose the sample size that minimizes the average cost per subject. The second is to choose sample size to minimize total cost divided by the square root of sample size. This latter method is theoretically more justifiable for innovative studies, but also performs reasonably well and has some justification in other cases. For example, if projected study value is assumed to be proportional to power at a specific alternative and total cost is a linear function of sample size, then this approach is guaranteed either to produce more than 90% power or to be more cost efficient than any sample size that does. These methods are easy to implement, based on reliable inputs, and well justified, so they should be regarded as acceptable alternatives to current conventional approaches. PMID:18482055

RF Design of a High Average Beam-Power SRF Electron Source

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

Sipahi, Nihan; Biedron, Sandra; Gonin, Ivan

2016-06-01

There is a significant interest in developing high-average power electron sources, particularly in the area of electron sources integrated with Superconducting Radio Frequency (SRF) systems. For these systems, the electron gun and cathode parts are critical components for stable intensity and high-average powers. In this initial design study, we will present the design of a 9-cell accelerator cavity having a frequency of 1.3 GHz and the corresponding field optimization studies.

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

Galvin, M.J.; MacNichols, G.L.; McRee, D.I.

In this study, the influence of 2450 MHz CW microwave radiation on hematopoiesis in pregnant mice was examined. Dams (mice CD-1 strain) were irradiated during Days 1-6 or 6-15 of pregnancy. The animals were irradiated for a total of 8 hr per day at an average power density of 30 mW/cm/sup 2/. Peripheral blood and bone marrow samples were obtained on Day 18 of pregnancy. The total leukocyte and differential leukocyte counts of peripheral blood samples were not affected by either exposure regimen. In addition, no effects were noted in either the erythroid or myeloid mitotic indices of bone marrowmore » samples. Exposure of pregnant mice to microwave radiation under the conditions of these experiments had no effects on the investigated aspects of hematopoiesis.« less

Dynamic Changes in Spectral and Spatial Signatures of High Frequency Oscillations in Rat Hippocampi during Epileptogenesis in Acute and Chronic Stages.

PubMed

Song, Pan-Pan; Xiang, Jing; Jiang, Li; Chen, Heng-Sheng; Liu, Ben-Ke; Hu, Yue

2016-01-01

To analyze spectral and spatial signatures of high frequency oscillations (HFOs), which include ripples and fast ripples (FRs, >200 Hz) by quantitatively assessing average and peak spectral power in a rat model of different stages of epileptogenesis. The lithium-pilocarpine model of temporal lobe epilepsy was used. The acute phase of epilepsy was assessed by recording intracranial electroencephalography (EEG) activity for 1 day after status epilepticus (SE). The chronic phase of epilepsy, including spontaneous recurrent seizures (SRSs), was assessed by recording EEG activity for 28 days after SE. Average and peak spectral power of five frequency bands of EEG signals in CA1, CA3, and DG regions of the hippocampus were analyzed with wavelet and digital filter. FRs occurred in the hippocampus in the animal model. Significant dynamic changes in the spectral power of FRS were identified in CA1 and CA3. The average spectral power of ripples increased at 20 min before SE ( p  < 0.05), peaked at 10 min before diazepam injection. It decreased at 10 min after diazepam ( p  < 0.05) and returned to baseline after 1 h. The average spectral power of FRs increased at 30 min before SE ( p  < 0.05) and peaked at 10 min before diazepam. It decreased at 10 min after diazepam ( p  < 0.05) and returned to baseline at 2 h after injection. The dynamic changes were similar between average and peak spectral power of FRs. Average and peak spectral power of both ripples and FRs in the chronic phase showed a gradual downward trend compared with normal rats 14 days after SE. The spectral power of HFOs may be utilized to distinguish between normal and pathologic HFOs. Ictal average and peak spectral power of FRs were two parameters for predicting acute epileptic seizures, which could be used as a new quantitative biomarker and early warning marker of seizure. Changes in interictal HFOs power in the hippocampus at the chronic stage may be not related to seizure occurrence.

Determinants of mobile phone output power in a multinational study: implications for exposure assessment.

PubMed

Vrijheid, M; Mann, S; Vecchia, P; Wiart, J; Taki, M; Ardoino, L; Armstrong, B K; Auvinen, A; Bédard, D; Berg-Beckhoff, G; Brown, J; Chetrit, A; Collatz-Christensen, H; Combalot, E; Cook, A; Deltour, I; Feychting, M; Giles, G G; Hepworth, S J; Hours, M; Iavarone, I; Johansen, C; Krewski, D; Kurttio, P; Lagorio, S; Lönn, S; McBride, M; Montestrucq, L; Parslow, R C; Sadetzki, S; Schüz, J; Tynes, T; Woodward, A; Cardis, E

2009-10-01

The output power of a mobile phone is directly related to its radiofrequency (RF) electromagnetic field strength, and may theoretically vary substantially in different networks and phone use circumstances due to power control technologies. To improve indices of RF exposure for epidemiological studies, we assessed determinants of mobile phone output power in a multinational study. More than 500 volunteers in 12 countries used Global System for Mobile communications software-modified phones (GSM SMPs) for approximately 1 month each. The SMPs recorded date, time, and duration of each call, and the frequency band and output power at fixed sampling intervals throughout each call. Questionnaires provided information on the typical circumstances of an individual's phone use. Linear regression models were used to analyse the influence of possible explanatory variables on the average output power and the percentage call time at maximum power for each call. Measurements of over 60,000 phone calls showed that the average output power was approximately 50% of the maximum, and that output power varied by a factor of up to 2 to 3 between study centres and network operators. Maximum power was used during a considerable proportion of call time (39% on average). Output power decreased with increasing call duration, but showed little variation in relation to reported frequency of use while in a moving vehicle or inside buildings. Higher output powers for rural compared with urban use of the SMP were observed principally in Sweden where the study covered very sparsely populated areas. Average power levels are substantially higher than the minimum levels theoretically achievable in GSM networks. Exposure indices could be improved by accounting for average power levels of different telecommunications systems. There appears to be little value in gathering information on circumstances of phone use other than use in very sparsely populated regions.

Evaluation of a regional monitoring program's statistical power to detect temporal trends in forest health indicators

USGS Publications Warehouse

Perles, Stephanie J.; Wagner, Tyler; Irwin, Brian J.; Manning, Douglas R.; Callahan, Kristina K.; Marshall, Matthew R.

2014-01-01

Forests are socioeconomically and ecologically important ecosystems that are exposed to a variety of natural and anthropogenic stressors. As such, monitoring forest condition and detecting temporal changes therein remain critical to sound public and private forestland management. The National Parks Service’s Vital Signs monitoring program collects information on many forest health indicators, including species richness, cover by exotics, browse pressure, and forest regeneration. We applied a mixed-model approach to partition variability in data for 30 forest health indicators collected from several national parks in the eastern United States. We then used the estimated variance components in a simulation model to evaluate trend detection capabilities for each indicator. We investigated the extent to which the following factors affected ability to detect trends: (a) sample design: using simple panel versus connected panel design, (b) effect size: increasing trend magnitude, (c) sample size: varying the number of plots sampled each year, and (d) stratified sampling: post-stratifying plots into vegetation domains. Statistical power varied among indicators; however, indicators that measured the proportion of a total yielded higher power when compared to indicators that measured absolute or average values. In addition, the total variability for an indicator appeared to influence power to detect temporal trends more than how total variance was partitioned among spatial and temporal sources. Based on these analyses and the monitoring objectives of theVital Signs program, the current sampling design is likely overly intensive for detecting a 5 % trend·year−1 for all indicators and is appropriate for detecting a 1 % trend·year−1 in most indicators.

47 CFR 15.403 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... between several transmission power levels in the data transmission process. (s) U-NII devices. Intentional... bridge in a peer-to-peer connection or as a connector between the wired and wireless segments of the... the presence of a radar. (c) Average Symbol Envelope Power. The average symbol envelope power is the...

Onshore-offshore wind energy resource evaluation based on synergetic use of multiple satellite data and meteorological stations in Jiangsu Province, China

NASA Astrophysics Data System (ADS)

Wei, Xianglin; Duan, Yuewei; Liu, Yongxue; Jin, Song; Sun, Chao

2018-05-01

The demand for efficient and cost-effective renewable energy is increasing as traditional sources of energy such as oil, coal, and natural gas, can no longer satisfy growing global energy demands. Among renewable energies, wind energy is the most prominent due to its low, manageable impacts on the local environment. Based on meteorological data from 2006 to 2014 and multi-source satellite data (i.e., Advanced Scatterometer, Quick Scatterometer, and Windsat) from 1999 to 2015, an assessment of the onshore and offshore wind energy potential in Jiangsu Province was performed by calculating the average wind speed, average wind direction, wind power density, and annual energy production (AEP). Results show that Jiangsu has abundant wind energy resources, which increase from inland to coastal areas. In onshore areas, wind power density is predominantly less than 200 W/m2, while in offshore areas, wind power density is concentrates in the range of 328-500 W/m2. Onshore areas comprise more than 13,573.24 km2, mainly located in eastern coastal regions with good wind farm potential. The total wind power capacity in onshore areas could be as much as 2.06 x 105 GWh. Meanwhile, offshore wind power generation in Jiangsu Province is calculated to reach 2 x 106 GWh, which is approximately four times the electricity demand of the entire Jiangsu Province. This study validates the effective application of Advanced Scatterometer, Quick Scatterometer, and Windsat data to coastal wind energy monitoring in Jiangsu. Moreover, the methodology used in this study can be effectively applied to other similar coastal zones.

Creatine, arginine alpha-ketoglutarate, amino acids, and medium-chain triglycerides and endurance and performance.

PubMed

Little, Jonathan P; Forbes, Scott C; Candow, Darren G; Cornish, Stephen M; Chilibeck, Philip D

2008-10-01

Creatine (Cr) supplementation increases muscle mass, strength, and power. Arginine a-ketoglutarate (A-AKG) is a precursor for nitric oxide production and has the potential to improve blood flow and nutrient delivery (i.e., Cr) to muscles. This study compared a commercial dietary supplement of Cr, A-AKG, glutamine, taurine, branched-chain amino acids, and medium-chain triglycerides with Cr alone or placebo on exercise performance and body composition. Thirty-five men (approximately 23 yr) were randomized to Cr + A-AKG (0.1 g . kg(-1) . d(-1) Cr + 0.075 g . kg(-1) . d(-1)A-AKG, n = 12), Cr (0.1 g . kg(-1) . d(-1), n = 11), or placebo (1 g . kg(-1) . d(-1) sucrose, n = 12) for 10 d. Body composition, muscle endurance (bench press), and peak and average power (Wingate tests) were measured before and after supplementation. Bench-press repetitions over 3 sets increased with Cr + A-AKG (30.9 +/- 6.6 +/- 34.9 +/- 8.7 reps; p < .01) and Cr (27.6 +/- 5.9 +/- 31.0 +/- 7.6 reps; p < .01), with no change for placebo (26.8 +/- 5.0 +/- 27.1 +/- 6.3 reps). Peak power significantly increased in Cr + A-AKG (741 +/- 112 +/- 794 +/- 92 W; p < .01), with no changes in Cr (722 +/- 138 +/- 730 +/- 144 W) and placebo (696 +/- 63 +/- 705 +/- 77 W). There were no differences in average power between groups over time. Only the Cr-only group increased total body mass (79.9 +/- 13.0 +/- 81.1 +/- 13.8 kg; p < .01), with no significant changes in lean-tissue or fat mass. These results suggest that Cr alone and in combination with A-AKG improves upper body muscle endurance, and Cr + A-AKG supplementation improves peak power output on repeated Wingate tests.

The effects of combining elastic and free weight resistance on strength and power in athletes.

PubMed

Anderson, Corey E; Sforzo, Gary A; Sigg, John A

2008-03-01

This study was undertaken to determine whether combined elastic and free weight resistance (CR) provides different strength and power adaptations than free weight resistance (FWR) training alone. Forty-four young (age 20 +/- 1 years), resistance-trained (4 +/- 2 years' experience) subjects were recruited from men's basketball and wrestling teams and women's basketball and hockey teams at Cornell University. Subjects were stratified according to team, then randomly assigned to the control (C; n = 21) or experimental group (E; n = 23). Before and after 7 weeks of resistance training, subjects were tested for lean body mass, 1 repetition maximum back squat and bench press, and peak and average power. Both C and E groups performed identical workouts except that E used CR (i.e., elastic resistance) for the back squat and bench press, whereas the C group used FWR alone. CR was performed using an elastic bungee cord attached to a standard barbell loaded with plates. Elastic tension was accounted for in an attempt to equalize the total work done by each group. Statistical analyses revealed significant (P < 0.05) between-group differences after training. Compared with C, improvement for E was nearly three times greater for back squat (16.47 +/- 5.67 vs. 6.84 +/- 4.42 kg increase), two times greater for bench press (6.68 +/- 3.41 vs. 3.34 +/- 2.67 kg increase), and nearly three times greater for average power (68.55 +/- 84.35 vs. 23.66 +/- 40.56 watt increase). Training with CR may be better than FWR alone for developing lower and upper body strength, and lower body power in resistance-trained individuals. Long-term effects are unclear, but CR training makes a meaningful contribution in the short term to performance adaptations of experienced athletes.

Radiofrequency Electromagnetic Field Map of Timisoara

NASA Astrophysics Data System (ADS)

Stefu, N.; Solyom, I.; Arama, A.

2015-12-01

There are many electromagnetic field (EMF) sources nowadays acting simultaneously, especially in urban areas, making the theoretical estimation of electromagnetic power at ground level very difficult. This paper reports on EMF maps built with measurements collected in Timisoara, at various radiofrequencies. A grid of 15×15 squares was built (approximate resolution 400m x 400m) and measurements of the average and maximum values of the electric field E, magnetic field H and total power density S at 0.9, 1.8 and 2.4 GHz were collected in every node of the grid. Positions of the nodes in terms of latitude and longitude were also collected. Maps were built presenting the spatial distribution of the measured quantities over Timisoara. Potential influences of EMF on public health are discussed.

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

Osterwald, C. R.; Anderberg, A.; Rummel, S.

We present an analysis of the results of a solar weathering program that found a linear relationship between maximum power degradation and the total UV exposure dose for four different types of commercial crystalline Si modules. The average degradation rate for the four modules types was 0.71% per year. The analysis showed that losses of short-circuit current were responsible for the maximum power degradation. Judging by the appearance of the undegraded control modules, it is very doubtful that the short-circuit current losses were caused by encapsulation browning or obscuration. When we compared the quantum efficiency of a single cell inmore » a degraded module to one from an unexposed control module, it appears that most of the degradation has occurred in the 800 - 1100 nm wave-length region, and not the short wavelength region.« less

ON THE STAR FORMATION LAW FOR SPIRAL AND IRREGULAR GALAXIES

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

Elmegreen, Bruce G., E-mail: bge@us.ibm.com

2015-12-01

A dynamical model for star formation on a galactic scale is proposed in which the interstellar medium is constantly condensing to star-forming clouds on the dynamical time of the average midplane density, and the clouds are constantly being disrupted on the dynamical timescale appropriate for their higher density. In this model, the areal star formation rate scales with the 1.5 power of the total gas column density throughout the main regions of spiral galaxies, and with a steeper power, 2, in the far outer regions and in dwarf irregular galaxies because of the flaring disks. At the same time, theremore » is a molecular star formation law that is linear in the main and outer parts of disks and in dIrrs because the duration of individual structures in the molecular phase is also the dynamical timescale, canceling the additional 0.5 power of surface density. The total gas consumption time scales directly with the midplane dynamical time, quenching star formation in the inner regions if there is no accretion, and sustaining star formation for ∼100 Gyr or more in the outer regions with no qualitative change in gas stability or molecular cloud properties. The ULIRG track follows from high densities in galaxy collisions.« less

Record Blizzard Buries U.S. Northeast

NASA Technical Reports Server (NTRS)

2005-01-01

After two days of blustery weather, the skies cleared over Massachusetts on January 24, 2005. Along with other northeastern U.S. states, Massachusetts was slammed with a powerful blizzard on January 22 and 23 that shut down travel and businesses and extinguished power. The storm brought record snow to many places, but Massachusetts topped the list. The cities of Salem and Plymouth were buried in 38 inches (96.5 cm) of snow, and strong winds created drifts up to seven feet (2 meters) high, according to the National Weather Service. For Boston, the storm was the fifth worst blizzard to hit the city since 1892, dumping 22.5 inches (57 cm) of snow in two days. Of that, 13.4 inches (34 cm) fell on January 23' the most snow to fall on the city in a single day since records began. These totals gave Boston nearly twice its average snowfall for January (the average is 13.5 inches, 34.3 cm), and over half its annual average snow of 41.8 inches (106 cm). This Moderate Resolution Imaging Spectroradiometer (MODIS) image, taken on January 24 by NASA's Terra satellite, shows the effects of the storm on Massachusetts and its southern neighbors, Connecticut (left) and Rhode Island (right). New York's Long Island is in the lower left corner of the image. The entire region is coated with snow, though clouds obscure the ground on the left side of the image. The snow was accompanied by powerful hurricane-force winds that helped create white-out conditions and large snowdrifts. The wind also churned ocean waters around Cape Cod, leaving them milky with sediment. NASA image courtesy the MODIS Rapid Response Team at NASA GSFC.

Q-switched and mode-locked Er{sup 3+}-doped fibre laser using a single-multi-single fibre filter and piezoelectric

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

Ji Wang; Yunjun Zhang; Aotuo Dong

2014-04-28

The active Q-switched and passive mode-locked Er{sup 3+}-doped all-fibre laser is presented. The fibre laser centre wavelength is located at 1563 nm and determined by the homemade singlemulti- single (SMS) in-line fibre filter. The laser spectrum width is nearly 0.1 nm. The active Q-switched mechanism relies on the polarisation state control using a piezoelectric to press a segment of passive fibre on the circular cavity. The nonlinear polarisation rotation technology is used to realise the passive self-started modelocked operation. In the passive mode-locked regimes, the output average power is 2.1 mW, repetition frequency is 11.96 MHz, and single pulse energymore » is 0.18 nJ. With the 100-Hz Q-switched regimes running, the output average power is 1.5 mW. The total Q-switched pulse width is 15 μs, and every Q-switched pulse is made up by several tens of mode-locked peak pulses. The calculated output pulse energy of the Q-switched fibre laser is about 15 μJ, and the energy of every mode-locked pulse is about 64–68 nJ during a Q-switched pulse taking into account the power fraction propagating between pulses. (lasers)« less

Transionospheric Propagation of VLF Transmitter Signals

NASA Astrophysics Data System (ADS)

Cohen, M.; Inan, U. S.; Lehtinen, N. G.

2012-12-01

Ground based Very Low Frequency (VLF, 3-30 kHz) radio transmitters may play a significant role in precipitation of inner belt (L<2.5) energetic Van Allen electrons. Initial analyses of the total contribution of VLF transmitters utilized models of transionospheric propagation, but some recent studies have suggested that those models may overestimate (by 20-100 dB) the VLF energy reaching the magnetosphere. One possible cause of this discrepancy was suggested to be conversion of wave energy into electrostatic modes in the D, E, and F regions, from ionospheric density irregularities, either natural or generated by the transmitter heating itself. The DEMETER satellite built a six year history of continuous and global survey mode data which, when combined, yields detailed pictures of the radiation pattern from many transmitters into space at 680 km, with 25 km resolution, and clear features like the interference pattern on the ground mapped upwards. With both E and B survey mode data, we can also directly approximate the total power injected into the magnetosphere from each transmitter, separately for day and night, as well as the power arriving at the conjugate region. We find no detectable variation of signal intensity with geomagnetic conditions. We find evidence of transmitter heating affecting the transionospheric propagation of other transmitters. We find that the power reaching the conjugate region is a large fraction of the power injected above the transmitter. We then employ a full wave model to simulate VLF transmitter transionospheric propagation, calculating the electromagnetic fields and power flux injected into the magnetosphere. Although the model does not include ionospheric irregularities, the radiation pattern largely matches the observed one, and the total power calculated is within 6 dB of observations for every transmitter, both day and night, and across a range of low to middle latitudes and transmitter powers. We thus conclude that the effect of ionospheric irregularities on VLF wave injection into the radiation belts may be small, if present at all.The nighttime radiation pattern of NWC at 700 km altitude, derived by averaging 6 years of DEMETER survey mode data.

Comparison of Muscle Recovery Following Bi-cruciate Substituting versus Posterior Stabilized Total Knee Arthroplasty in the Asian Population.

PubMed

Takubo, Akihito; Ryu, Keinosuke; Iriuchishima, Takanori; Tokuhashi, Yasuaki

2017-09-01

The purpose of this study was to compare muscle recovery in the lower extremities following the newly developed bi-cruciate substituting (BCS) to posterior stabilized (PS) total knee arthroplasty (TKA) in the Asian population. Forty-one knees in 41 patients undergoing BCS-TKA (41 female, average age: 71 ± 8.8) and 34 knees in 34 patients undergoing PS-TKA (33 female, average age: 73 ± 7.2) were included in this study. The maximum isometric power of the quadriceps and hamstring muscles was measured preoperatively, and at 1, 3, 6, and 12 months after surgery using a handheld dynamometer. Postoperative muscle recovery was calculated regarding preoperative muscle power as 100%. Pre- and postoperative range of knee motion, femorotibial angle, and clinical scores (Knee Society score and function score) were also compared. No significant difference in sex, age, preoperative quadriceps, or preoperative hamstring power was observed between the BCS and PS-TKA groups. When regarding the preoperative muscle power as 100%, quadriceps power at 1, 3, 6, and 12 months following BCS-TKA was 61.2 ± 22%, 86.3 ± 28.3%, 97 ± 27.4%, and 112.4 ± 30.8%, respectively. Quadriceps power at 1, 3, 6, and 12 months following PS-TKA was 72.4 ± 20.8%, 84 ± 16.9%, 95 ± 20.7%, and 110.8 ± 27%, respectively. Hamstring power at 1, 3, 6, and 12 months following BCS-TKA was 96.3 ± 30%, 111.4 ± 35%, 120 ± 37%, and 125 ± 31%, respectively. Hamstring power at 1, 3, 6, and 12 months following PS-TKA was 95 ± 25%, 112.4 ± 27%, 117 ± 38.5%, and 120.4 ± 18.5%, respectively. No significant difference in muscle power recovery was observed at 3 ( p  = 0.995), 6 ( p  = 0.944), and 12 ( p  = 0.917) months after surgery between the two groups. No significant difference of the clinical score was observed between the groups (Knee Society score: p  = 0.479, function score: p  = 0.342). No significant difference in muscle recovery and clinical score were observed between the BCS and PS-TKA groups. Longer follow-up is needed for the evaluation of efficacy of BCS-TKA in the Asian populations. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

650-nJ pulses from a cavity-dumped Yb:fiber-pumped ultrafast optical parametric oscillator

NASA Astrophysics Data System (ADS)

Lamour, Tobias P.; Reid, Derryck T.

2011-08-01

Sub-250-fs pulses with energies of up to 650 nJ and peak powers up to 2.07 MW were generated from a cavity-dumped optical parametric oscillator, synchronously-pumped at 15.3 MHz with sub-400-fs pulses from an Yb:fiber laser. The average beam quality factor of the dumped output was M2 ~1.2 and the total relative-intensity noise was 8 mdBc, making the system a promising candidate for ultrafast laser inscription of infrared materials.

Thermal conductance of and heat generation in tire-pavement interface and effect on aircraft braking

NASA Technical Reports Server (NTRS)

Miller, C. D.

1976-01-01

A finite-difference analysis was performed on temperature records obtained from a free rolling automotive tire and from pavement surface. A high thermal contact conductance between tire and asphalt was found on a statistical basis. Average slip due to squirming between tire and asphalt was about 1.5 mm. Consequent friction heat was estimated as 64 percent of total power absorbed by bias-ply, belted tire. Extrapolation of results to aircraft tire indicates potential braking improvement by even moderate increase of heat absorbing capacity of runway surface.

The research on the design and performance of 7×1 pump combiners

NASA Astrophysics Data System (ADS)

Cao, Yang; Sheng, Quan; Fu, Shijie; Zhang, Haiwei; Bai, Xiaolei; Shi, Wei; Yao, Jianquan

2018-02-01

The 7×1 end-pumped pump combiners employing 105/125 μm multimode fibers as pump fibers are investigated. Based on the results of our theoretical analysis, sufficient taper length (TL) and low refractive index (RI) of the capillary have been adopted to fabricate high transmission efficiency combiners. A 7×1 end-pumped pump combiner with an average transmission efficiency of 98.9% and a total return loss of 1.1‰ is fabricated in experiments, which could find its application in high-power fiber laser systems.

An Approach to Average Modeling and Simulation of Switch-Mode Systems

ERIC Educational Resources Information Center

Abramovitz, A.

2011-01-01

This paper suggests a pedagogical approach to teaching the subject of average modeling of PWM switch-mode power electronics systems through simulation by general-purpose electronic circuit simulators. The paper discusses the derivation of PSPICE/ORCAD-compatible average models of the switch-mode power stages, their software implementation, and…

18 CFR 301.5 - Changes in Average System Cost methodology.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Changes in Average System Cost methodology. 301.5 Section 301.5 Conservation of Power and Water Resources FEDERAL ENERGY... ACT § 301.5 Changes in Average System Cost methodology. (a) The Administrator, at his or her...

18 CFR 301.5 - Changes in Average System Cost methodology.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Changes in Average System Cost methodology. 301.5 Section 301.5 Conservation of Power and Water Resources FEDERAL ENERGY... ACT § 301.5 Changes in Average System Cost methodology. (a) The Administrator, at his or her...

18 CFR 301.5 - Changes in Average System Cost methodology.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Changes in Average System Cost methodology. 301.5 Section 301.5 Conservation of Power and Water Resources FEDERAL ENERGY... ACT § 301.5 Changes in Average System Cost methodology. (a) The Administrator, at his or her...

18 CFR 301.5 - Changes in Average System Cost methodology.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Changes in Average System Cost methodology. 301.5 Section 301.5 Conservation of Power and Water Resources FEDERAL ENERGY... ACT § 301.5 Changes in Average System Cost methodology. (a) The Administrator, at his or her...

Resting state cortical oscillations of patients with Parkinson disease and with and without subthalamic deep brain stimulation: a magnetoencephalography study.

PubMed

Cao, Chunyan; Li, Dianyou; Jiang, Tianxiao; Ince, Nuri Firat; Zhan, Shikun; Zhang, Jing; Sha, Zhiyi; Sun, Bomin

2015-04-01

In this study, we investigate the modification to cortical oscillations of patients with Parkinson disease (PD) by subthalamic deep brain stimulation (STN-DBS). Spontaneous cortical oscillations of patients with PD were recorded with magnetoencephalography during on and off subthalamic nucleus deep brain stimulation states. Several features such as average frequency, average power, and relative subband power in regions of interest were extracted in the frequency domain, and these features were correlated with Unified Parkinson Disease Rating Scale III evaluation. The same features were also investigated in patients with PD without surgery and healthy controls. Patients with Parkinson disease without surgery compared with healthy controls had a significantly lower average frequency and an increased average power in 1 to 48 Hz range in whole cortex. Higher relative power in theta and simultaneous decrease in beta and gamma over temporal and occipital were also observed in patients with PD. The Unified Parkinson Disease Rating Scale III rigidity score correlated with the average frequency and with the relative power of beta and gamma in frontal areas. During subthalamic nucleus deep brain stimulation, the average frequency increased significantly when stimulation was on compared with off state. In addition, the relative power dropped in delta, whereas it rose in beta over the whole cortex. Through the course of stimulation, the Unified Parkinson Disease Rating Scale III rigidity and tremor scores correlated with the relative power of alpha over left parietal. Subthalamic nucleus deep brain stimulation improves the symptoms of PD by suppressing the synchronization of alpha rhythm in somatomotor region.

Power absorbed during whole-body vertical vibration: Effects of sitting posture, backrest, and footrest

NASA Astrophysics Data System (ADS)

Nawayseh, Naser; Griffin, Michael J.

2010-07-01

Previous studies have quantified the power absorbed in the seated human body during exposure to vibration but have not investigated the effects of body posture or the power absorbed at the back and the feet. This study investigated the effects of support for the feet and back and the magnitude of vibration on the power absorbed during whole-body vertical vibration. Twelve subjects were exposed to four magnitudes (0.125, 0.25, 0.625, and 1.25 m s -2 rms) of random vertical vibration (0.25-20 Hz) while sitting on a rigid seat in four postures (feet hanging, maximum thigh contact, average thigh contact, and minimum thigh contact) both with and without a rigid vertical backrest. Force and acceleration were measured at the seat, the feet, and the backrest to calculate the power absorbed at these three locations. At all three interfaces (seat, feet, and back) the absorbed power increased in proportion to the square of the magnitude of vibration, with most power absorbed from vibration at the seat. Supporting the back with the backrest decreased the power absorbed at the seat at low frequencies but increased the power absorbed at high frequencies. Supporting the feet with the footrest reduced the total absorbed power at the seat, with greater reductions with higher footrests. It is concluded that contact between the thighs and the seat increases the power absorbed at the seat whereas a backrest can either increase or decrease the power absorbed at the seat.

A Non-condensing Thermal Compression Power Generation System

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

McGrail, B. P.; Jenks, J. J.; Abrams, W. P.

Organic Rankine cycle (ORC) systems have attracted interest for more than three decades due to advantages in operation at lower working temperature, low maintenance requirements, and relative simplicity (fewer components). In theory, these advantages should make ORC technology more economically attractive for the small and medium power scales (10 kW to 10 MW). Unfortunately, the theoretical promise of ORC systems for power generation has been realized at only a relatively small fraction of the potential market. Although there are a number of reasons for the low utilization of ORC technology, the root cause is directly tied to the relatively lowmore » heat-to-power conversion efficiency (2 to 7% typically) and high cost of specially designed expander–generator equipment that is up to 60% of total system cost. The resulting high cost of the power produced just does not make economic sense except in very specialized situations where on-site power is needed but unavailable (at any cost) or where local generation costs are well above regional averages. The overarching objective of the work presented here is to break this paradigm by developing and demonstrating a new harmonic adsorption recuperative power cycle (HARP) system that offers 40% more efficient power generation as compared with a standard ORC system and estimated electric power production costs at very competitive rates below $0.10/kWh.« less

A Non-condensing Thermal Compression Power Generation System

DOE PAGES

McGrail, B. P.; Jenks, J. J.; Abrams, W. P.; ...

2017-09-12

Organic Rankine cycle (ORC) systems have attracted interest for more than three decades due to advantages in operation at lower working temperature, low maintenance requirements, and relative simplicity (fewer components). In theory, these advantages should make ORC technology more economically attractive for the small and medium power scales (10 kW to 10 MW). Unfortunately, the theoretical promise of ORC systems for power generation has been realized at only a relatively small fraction of the potential market. Although there are a number of reasons for the low utilization of ORC technology, the root cause is directly tied to the relatively lowmore » heat-to-power conversion efficiency (2 to 7% typically) and high cost of specially designed expander–generator equipment that is up to 60% of total system cost. The resulting high cost of the power produced just does not make economic sense except in very specialized situations where on-site power is needed but unavailable (at any cost) or where local generation costs are well above regional averages. The overarching objective of the work presented here is to break this paradigm by developing and demonstrating a new harmonic adsorption recuperative power cycle (HARP) system that offers 40% more efficient power generation as compared with a standard ORC system and estimated electric power production costs at very competitive rates below $0.10/kWh.« less

Improvement of two-photon microscopic imaging in deep regions of living mouse brains by utilizing a light source based on an electrically controllable gain-switched laser diode

NASA Astrophysics Data System (ADS)

Sawada, Kazuaki; Kawakami, Ryosuke; Fang, Yi-Cheng; Hung, Jui-Hung; Kozawa, Yuichi; Otomo, Kohei; Sato, Shunichi; Yokoyama, Hiroyuki; Nemoto, Tomomi

2018-02-01

In vivo two-photon microscopy is an advantageous technique for observing living mouse brains at high spatial resolutions. We previously used a 1064 nm high-power light source based on an electrically controllable gain-switched laser diode (maximum power: 4 W, repetition rate: 10 MHz, pulse width: 7.5 picoseconds) and successfully visualized EYFP expressing neurons at deeper regions in H-line mouse brains under living conditions. However, severe damages were frequently observed when the laser power after the objective lens was over 600 mW, suggesting that a higher average power might not be suitable for visualizing neural structures and functions at deep regions. To increase fluorescent signals as a strategy to avoid such invasions, here, we evaluated the effects of the excitation laser parameters such as the repetition rate (5 - 10 MHz), or the peak power, at the moderate average powers (10 - 500 mW), by taking the advantage that this electrically controllable light source could be used to change the repetition rate independently from the average power or the pulse width. The fluorescent signals of EYFP at layer V of the cerebral cortex were increased by approximately twofold when the repetition rate was decreased from 10 MHz to 5 MHz at the same average power. We also confirmed similar effects in the EYFP solution (335 μM) and fixed brain slices. These results suggest that in vivo two-photon microscopic imaging might be improved by increasing the peak power at the same average power while avoiding the severe damages in living brains.

Theoretical study of enhancing the piezoelectric nanogenerator's output power by optimizing the external force's shape

NASA Astrophysics Data System (ADS)

Xu, Qi; Qin, Yong

2017-07-01

The average power is one of the key parameters of piezoelectric nanogenerators (PENGs). In this paper, we demonstrate that the PENG's output can be gigantically improved by choosing driving force with an appropriate shape. When the load resistance is 100 MΩ and the driven forces have a magnitude of 19.6 nN, frequency of 10 Hz, the average power of PENG driven by square shaped force is six orders of magnitude higher than that driven by triangular shaped and sinusoidal shaped forces. These results are of importance for optimizing the average power of the PENGs in practical applications.

High average power scaleable thin-disk laser

DOEpatents

Beach, Raymond J.; Honea, Eric C.; Bibeau, Camille; Payne, Stephen A.; Powell, Howard; Krupke, William F.; Sutton, Steven B.

2002-01-01

Using a thin disk laser gain element with an undoped cap layer enables the scaling of lasers to extremely high average output power values. Ordinarily, the power scaling of such thin disk lasers is limited by the deleterious effects of amplified spontaneous emission. By using an undoped cap layer diffusion bonded to the thin disk, the onset of amplified spontaneous emission does not occur as readily as if no cap layer is used, and much larger transverse thin disks can be effectively used as laser gain elements. This invention can be used as a high average power laser for material processing applications as well as for weapon and air defense applications.

Pilot study for quantifying driving characteristics during power wheelchair soccer.

PubMed

Kumar, Amit; Karmarkar, Amol M; Collins, Diane M; Souza, Ana; Oyster, Michelle L; Cooper, Rosemarie; Cooper, Rory A

2012-01-01

This study determined the driving characteristics of wheelchair users during power wheelchair soccer games. Data for this study were collected at the 28th and 29th National Veterans Wheelchair Games. Nineteen veterans who were 18 years or older and power wheelchair soccer players completed a brief demographic survey and provided information about their power wheelchairs. A customized data-logging device was placed on each participant's wheelchair before power soccer game participation. The data logger was removed at the end of the final game for each participant. The average distance traveled during the games was 899.5 +/- 592.5 m, and the average maximum continuous distance traveled was 256.0 +/- 209.4 m. The average wheelchair speed was 0.8 +/- 0.2 m/s, and the average duration of driving time was 17.6 +/- 8.3 min. Average proportion of time spent at a speed >1 m/s was 30.7% +/- 33.8%, between 0.5 and 1 m/s was 16.2% +/- 34.4%, and <0.5 m/s was 21.4% +/- 24.3%. The information from this descriptive study provides insight for future research in the field of adapted sports for people with high levels of impairments who use power wheelchairs for their mobility.

Econophysics of adaptive power markets: When a market does not dampen fluctuations but amplifies them

NASA Astrophysics Data System (ADS)

Krause, Sebastian M.; Börries, Stefan; Bornholdt, Stefan

2015-07-01

The average economic agent is often used to model the dynamics of simple markets, based on the assumption that the dynamics of a system of many agents can be averaged over in time and space. A popular idea that is based on this seemingly intuitive notion is to dampen electric power fluctuations from fluctuating sources (as, e.g., wind or solar) via a market mechanism, namely by variable power prices that adapt demand to supply. The standard model of an average economic agent predicts that fluctuations are reduced by such an adaptive pricing mechanism. However, the underlying assumption that the actions of all agents average out on the time axis is not always true in a market of many agents. We numerically study an econophysics agent model of an adaptive power market that does not assume averaging a priori. We find that when agents are exposed to source noise via correlated price fluctuations (as adaptive pricing schemes suggest), the market may amplify those fluctuations. In particular, small price changes may translate to large load fluctuations through catastrophic consumer synchronization. As a result, an adaptive power market may cause the opposite effect than intended: Power demand fluctuations are not dampened but amplified instead.

Average power scaling of UV excimer lasers drives flat panel display and lidar applications

NASA Astrophysics Data System (ADS)

Herbst, Ludolf; Delmdahl, Ralph F.; Paetzel, Rainer

2012-03-01

Average power scaling of 308nm excimer lasers has followed an evolutionary path over the last two decades driven by diverse industrial UV laser microprocessing markets. Recently, a new dual-oscillator and beam management concept for high-average power upscaling of excimer lasers has been realized, for the first time enabling as much as 1.2kW of stabilized UV-laser average output power at a UV wavelength of 308nm. The new dual-oscillator concept enables low temperature polysilicon (LTPS) fabrication to be extended to generation six glass substrates. This is essential in terms of a more economic high-volume manufacturing of flat panel displays for the soaring smartphone and tablet PC markets. Similarly, the cost-effective production of flexible displays is driven by 308nm excimer laser power scaling. Flexible displays have enormous commercial potential and can largely use the same production equipment as is used for rigid display manufacturing. Moreover, higher average output power of 308nm excimer lasers aids reducing measurement time and improving the signal-to-noise ratio in the worldwide network of high altitude Raman lidar stations. The availability of kW-class 308nm excimer lasers has the potential to take LIDAR backscattering signal strength and achievable altitude to new levels.

High sustained average power cw and ultrafast Yb:YAG near-diffraction-limited cryogenic solid-state laser.

PubMed

Brown, David C; Singley, Joseph M; Kowalewski, Katie; Guelzow, James; Vitali, Victoria

2010-11-22

We report what we believe to be record performance for a high average power Yb:YAG cryogenic laser system with sustained output power. In a CW oscillator-single-pass amplifier configuration, 963 W of output power was measured. In a second configuration, a two amplifier Yb:YAG cryogenic system was driven with a fiber laser picosecond ultrafast oscillator at a 50 MHz repetition rate, double-passed through the first amplifier and single-passed through the second, resulting in 758 W of average power output. Pulses exiting the system have a FWHM pulsewidth of 12.4 ps, an energy/pulse of 15.2 μJ, and a peak power of 1.23 MW. Both systems are force convection-cooled with liquid nitrogen and have been demonstrated to run reliably over long time periods.

Development of high-average-power DPSSL with high beam quality

NASA Astrophysics Data System (ADS)

Nakai, Sadao; Kanabe, Tadashi; Kawashima, Toshiyuki; Yamanaka, Masanobu; Izawa, Yasukazu; Nakatuka, Masahiro; Kandasamy, Ranganathan; Kan, Hirofumi; Hiruma, Teruo; Niino, Masayuki

2000-08-01

The recent progress of high power diode laser is opening new fields of laser and its application. We are developing high average power diode pumped solid state laser DPSSL for laser fusion power plant, for space propulsion and for various applications in industry. The common features or requirements of our High Average-power Laser for Nuclear-fusion Application (HALNA) are large pulse energy with relatively low repetition of few tens Hz, good beam quality of order of diffraction limit and high efficiency more than 10%. We constructed HALNA 10 (10J X 10 Hz) and tested the performance to clarify the scalability to higher power system. We have obtained in a preliminary experiment a 8.5 J output energy at 0.5 Hz with beam quality of 2 times diffraction limited far-field pattern.

Fish Passage Center; Columbia Basin Fish and Wildlife Authority, 2000 Annual Report.

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

DeHart, Michele

2001-06-01

The year 2000 hydrosystem operations illustrated two main points: (1) that the NMFS Biological Opinion on the operations of the Federal Columbia River Power System (FCRPS) fish migration measures could not be met in a slightly below average water year, and; (2) the impacts and relationships of energy deregulation and volatile wholesale energy prices on the ability of the FCRPS to provide the Biological Opinion fish migration measures. In 2000, a slightly below average water year, the flow targets were not met and, when energy ''emergencies'' were declared, salmon protection measures were reduced. The 2000 migration year was a belowmore » average runoff volume year with an actual run off volume of 61.1 MAF or 96% of average. This year illustrated the ability of the hydro system to meet the migration protection measures established by the NMFS Biological Opinion. The winter operation of storage reservoirs was based upon inaccurate runoff volume forecasts which predicted a January-July runoff volume forecast at The Dalles of 102 to 105% of average, from January through June. Reservoir flood control drafts during the winter months occurred according to these forecasts. This caused an over-draft of reservoirs that resulted in less volume of water available for fish flow augmentation in the spring and the summer. The season Biological Opinion flow targets for spring and summer migrants at Lower Granite and McNary dams were not met. Several power emergencies were declared by BPA in the summer of 2000. The first in June was caused by loss of resources (WNP2 went off-line). The second and third emergencies were declared in August as a result of power emergencies in California and in the Northwest. The unanticipated effects of energy deregulation, power market volatility and rising wholesale electricity prices, and Californian energy deregulation reduced the ability of the FCRPS to implement fish protection measures. A Spill Plan Agreement was implemented in the FCRPS. Under this plan, spill hours were increased at Lower Monumental Dam. Spill volume at The Dalles was reduced and daytime spill tests were conducted at John Day and Bonneville Dams. Although provided for fish, most spill that occurred in 2000 was either in excess of project hydraulic capacity or excess generation. This effectively reduced the actual cost of the spill program. For the most part, spill in 2000 was managed to the waiver limits for total dissolved gas levels and the NMFS action criteria for dissolved gas signs were not exceeded. Hatchery spring chinook returns comprised an estimated 81.4% of the total spring chinook adult return to Lower Granite Dam. Smolt travel time and survival were similar to past years for most Smolt Monitoring Program groups. The notable exceptions were Snake River hatchery steelhead groups and mid-Columbia hatchery sub-yearling groups from Wells and Ringold hatcheries, which had significantly lower survival than previous years. Yearling chinook travel time showed variation from past years, reflecting the atypical flow shape in 2000 which had high flows in April, declining through May.« less

Measuring radio-signal power accurately

NASA Technical Reports Server (NTRS)

Goldstein, R. M.; Newton, J. W.; Winkelstein, R. A.

1979-01-01

Absolute value of signal power in weak radio signals is determined by computer-aided measurements. Equipment operates by averaging received signal over several-minute period and comparing average value with noise level of receiver previously calibrated.

Bias in discriminating very mild dementia for older adults with different levels of education in Hong Kong.

PubMed

Chang, Jianfang; Tse, Chi-Shing; Leung, Grace Tak Yu; Fung, Ada Wai Tung; Hau, Kit-Tai; Chiu, Helen Fung Kum; Lam, Linda Chiu Wa

2014-06-01

Education has a profound effect on older adults' cognitive performance. In Hong Kong, some dementia screening tasks were originally designed for developed population with, on average, higher education. We compared the screening power of these tasks for Chinese older adults with different levels of education. Community-dwelling older adults who were healthy (N = 383) and with very mild dementia (N = 405) performed the following tasks: Mini-Mental State Examination, Alzheimer's Disease Assessment Scale-Cognitive subscales, Verbal Fluency, Abstract Thinking, and Visual/Digit Span. Logistic regression was used to examine the power of these tasks to predict Clinical Dementia Rating (CDR 0.5 vs. 0). Logistic regression analysis showed that while the screening power of the total scores in all tasks was similar for high and low education groups, there were education biases in some items of these tasks. The differential screening power in high and low education groups was not identical across items in some tasks. Thus, in cognitive assessments, we should exercise great caution when using these potentially biased items for older adults with limited education.

Testing and Development of a Percussive Augmenter for Rotary Drills

NASA Technical Reports Server (NTRS)

Donnelly, Christopher; Bar-Cohen, Yoseph; Chang, Zensheu; Badescu, Mircea; Sherrit, Stewart

2011-01-01

Hammering drills are effective in fracturing the drilled medium while rotary drills remove cuttings. The combination provides a highly effective penetration mechanism. Piezoelectric actuators were integrated into an adapter to produce ultrasonic percussion; augmenting rotary drilling. The drill is capable of operating at low power, low applied force and, with proper tuning, low noise. These characteristics are of great interest for future NASA missions and the construction/remodeling industry. The developed augmenter connects a commercially available drill and bit and was tested to demonstrate its capability. Input power to the drill was read using a multimeter and the augmenter received a separate input voltage. The drive frequency of the piezoelectric actuator was controlled by a hill climb algorithm that optimizes and records average power usage to operate the drill at resonating frequency. Testing the rotary drill and augmenter across a range of combinations with total power constant at 160 Watts has shown results in concrete and limestone samples that are as good as or better than the commercial drill. The drill rate was increased 1.5 to over 10 times when compared to rotation alone.

Integration of Thermoelectric Generators and Wood Stove to Produce Heat, Hot Water, and Electrical Power

NASA Astrophysics Data System (ADS)

Goudarzi, A. M.; Mazandarani, P.; Panahi, R.; Behsaz, H.; Rezania, A.; Rosendahl, L. A.

2013-07-01

Traditional fire stoves are characterized by low efficiency. In this experimental study, the combustion chamber of the stove is augmented by two devices. An electric fan can increase the air-to-fuel ratio in order to increase the system's efficiency and decrease air pollution by providing complete combustion of wood. In addition, thermoelectric generators (TEGs) produce power that can be used to satisfy all basic needs. In this study, a water-based cooling system is designed to increase the efficiency of the TEGs and also produce hot water for residential use. Through a range of tests, an average of 7.9 W was achieved by a commercial TEG with substrate area of 56 mm × 56 mm, which can produce 14.7 W output power at the maximum matched load. The total power generated by the stove is 166 W. Also, in this study a reasonable ratio of fuel to time is described for residential use. The presented prototype is designed to fulfill the basic needs of domestic electricity, hot water, and essential heat for warming the room and cooking.

Performance of High-Efficiency Advanced Triple-Junction Solar Panels for the LILT Mission Dawn

NASA Technical Reports Server (NTRS)

Fatemi, Navid S.; Sharma, Surya; Buitrago, Oscar; Sharps, Paul R.; Blok, Ron; Kroon, Martin; Jalink, Cees; Harris, Robin; Stella, Paul; Distefano, Sal

2005-01-01

NASA's Discovery Mission Dawn is designed to (LILT) conditions. operate within the solar system's Asteroid belt, where the large distance from the sun creates a low-intensity, low-temperature (LILT) condition. To meet the mission power requirements under LlLT conditions, very high-efficiency multi-junction solar cells were selected to power the spacecraft to be built by Orbital Sciences Corporation (OSC) under contract with JPL. Emcore's InGaP/InGaAs/Ge advanced triple-junction (ATJ) solar cells, exhibiting an average air mass zero (AMO) efficiency of greater than 27.6% (one-sun, 28 C), were used to populate the solar panels [1]. The two solar array wings, to be built by Dutch Space, with 5 large- area panels each (total area of 36.4 sq. meters) are projected to produce between 10.3 kWe and 1.3 kWe of end-of life (EOL) power in the 1.0 to 3.0 AU range, respectively. The details of the solar panel design, testing and power analysis are presented.

Primordial anisotropies in gauged hybrid inflation

NASA Astrophysics Data System (ADS)

Akbar Abolhasani, Ali; Emami, Razieh; Firouzjahi, Hassan

2014-05-01

We study primordial anisotropies generated in the model of gauged hybrid inflation in which the complex waterfall field is charged under a U(1)gauge field. Primordial anisotropies are generated either actively during inflation or from inhomogeneities modulating the surface of end of inflation during waterfall transition. We present a consistent δN mechanism to calculate the anisotropic power spectrum and bispectrum. We show that the primordial anisotropies generated at the surface of end of inflation do not depend on the number of e-folds and therefore do not produce dangerously large anisotropies associated with the IR modes. Furthermore, one can find the parameter space that the anisotropies generated from the surface of end of inflation cancel the anisotropies generated during inflation, therefore relaxing the constrains on model parameters imposed from IR anisotropies. We also show that the gauge field fluctuations induce a red-tilted power spectrum so the averaged power spectrum from the gauge field can change the total power spectrum from blue to red. Therefore, hybrid inflation, once gauged under a U(1) field, can be consistent with the cosmological observations.

Corneal power evaluation after myopic corneal refractive surgery using artificial neural networks.

PubMed

Koprowski, Robert; Lanza, Michele; Irregolare, Carlo

2016-11-15

Efficacy and high availability of surgery techniques for refractive defect correction increase the number of patients who undergo to this type of surgery. Regardless of that, with increasing age, more and more patients must undergo cataract surgery. Accurate evaluation of corneal power is an extremely important element affecting the precision of intraocular lens (IOL) power calculation and errors in this procedure could affect quality of life of patients and satisfaction with the service provided. The available device able to measure corneal power have been tested to be not reliable after myopic refractive surgery. Artificial neural networks with error backpropagation and one hidden layer were proposed for corneal power prediction. The article analysed the features acquired from the Pentacam HR tomograph, which was necessary to measure the corneal power. Additionally, several billion iterations of artificial neural networks were conducted for several hundred simulations of different network configurations and different features derived from the Pentacam HR. The analysis was performed on a PC with Intel ® Xeon ® X5680 3.33 GHz CPU in Matlab ® Version 7.11.0.584 (R2010b) with Signal Processing Toolbox Version 7.1 (R2010b), Neural Network Toolbox 7.0 (R2010b) and Statistics Toolbox (R2010b). A total corneal power prediction error was obtained for 172 patients (113 patients forming the training set and 59 patients in the test set) with an average age of 32 ± 9.4 years, including 67% of men. The error was at an average level of 0.16 ± 0.14 diopters and its maximum value did not exceed 0.75 dioptres. The Pentacam parameters (measurement results) providing the above result are tangential anterial/posterior. The corneal net power and equivalent k-reading power. The analysis time for a single patient (a single eye) did not exceed 0.1 s, whereas the time of network training was about 3 s for 1000 iterations (the number of neurons in the hidden layer was 400).

22 W average power multiterawatt femtosecond laser chain enabling 1019 W/cm2 at 100 Hz

NASA Astrophysics Data System (ADS)

Clady, R.; Azamoum, Y.; Charmasson, L.; Ferré, A.; Utéza, O.; Sentis, M.

2018-05-01

We measure the wavefront distortions of a high peak power ultrashort (23 fs) laser system under high average power load. After 6 min—100 Hz operation of the laser at full average power (> 22 W after compression), the thermally induced wavefront distortions reach a steady state and the far-field profile of the laser beam no longer changes. By means of a deformable mirror located after the vacuum compressor, we apply a static pre-compensation to correct those aberrations allowing us to demonstrate a dramatic improvement of the far-field profile at 100 Hz with the reduction of the residual wavefront distortions below λ/16 before focusing. The applied technique provides 100 Hz operation of the femtosecond laser chain with stable pulse characteristics, corresponding to peak intensity above 1019 W/cm2 and average power of 19 W on target, which enables the study of relativistic optics at high repetition rate using a moderate f-number focusing optics ( f/4.5).

Receiver Signal to Noise Ratios for IPDA Lidars Using Sine-wave and Pulsed Laser Modulation and Direct Detections

NASA Technical Reports Server (NTRS)

Sun, Xiaoli; Abshire, James B.

2011-01-01

Integrated path differential absorption (IPDA) lidar can be used to remotely measure the column density of gases in the path to a scattering target [1]. The total column gas molecular density can be derived from the ratio of the laser echo signal power with the laser wavelength on the gas absorption line (on-line) to that off the line (off-line). 80th coherent detection and direct detection IPDA lidar have been used successfully in the past in horizontal path and airborne remote sensing measurements. However, for space based measurements, the signal propagation losses are often orders of magnitude higher and it is important to use the most efficient laser modulation and detection technique to minimize the average laser power and the electrical power from the spacecraft. This paper gives an analysis the receiver signal to noise ratio (SNR) of several laser modulation and detection techniques versus the average received laser power under similar operation environments. Coherent detection [2] can give the best receiver performance when the local oscillator laser is relatively strong and the heterodyne mixing losses are negligible. Coherent detection has a high signal gain and a very narrow bandwidth for the background light and detector dark noise. However, coherent detection must maintain a high degree of coherence between the local oscillator laser and the received signal in both temporal and spatial modes. This often results in a high system complexity and low overall measurement efficiency. For measurements through atmosphere the coherence diameter of the received signal also limits the useful size of the receiver telescope. Direct detection IPDA lidars are simpler to build and have fewer constraints on the transmitter and receiver components. They can use much larger size 'photon-bucket' type telescopes to reduce the demands on the laser transmitter. Here we consider the two most widely used direct detection IPDA lidar techniques. The first technique uses two CW seeder lasers, one on-line and one offline that are intensity modulated by two different frequency sine-waves signals before being amplified by a common laser amplifier. The receiver uses narrowband amplitude demodulation, or lock-in, Signal processing at the given laser modulation frequencies [3,4]. The laser transmitter operates in a quasi CW mode with the peak power equal to twice the average power. The on-line and off-line lasers can be transmitted at the same time without interference. Another direct detection technique uses a low duty cycle pulsed laser modulation [5,6] with the laser wavelengths alternating between on-line and off-line on successive pulses. The receiver uses time resolved detection and can also provide simultaneous target range measurement. With a lower laser duty cycle it requires a much higher peak laser power for the same average power.

Investigation of coaxial jet noise and inlet choking using an F-111A airplane

NASA Technical Reports Server (NTRS)

Putnam, T. W.

1973-01-01

Measurements of engine noise generated by an F-111A airplane positioned on a thrustmeasuring platform were made at angles of 0 deg to 160 deg from the aircraft heading. Sound power levels, power spectra, and directivity patterns are presented for jet exit velocities between 260 feet per second and 2400 feet per second. The test results indicate that the total acoustic power was proportional to the eighth power of the core jet velocity for core exhaust velocities greater than 300 meters per second (985 feet per second) and that little or no mixing of the core and fan streams occurred. The maximum sideline noise was most accurately predicted by using the average jet velocity for velocities above 300 meters per second (985 feet per second). The acoustic power spectrum was essentially the same for the single jet flow of afterburner operation and the coaxial flow of the nonafterburning condition. By varying the inlet geometry and cowl position, reductions in the sound pressure level of the blade passing frequency on the order of 15 decibels to 25 decibels were observed for inlet Mach numbers of 0.8 to 0.9.

A Low-Power High-Dynamic-Range Receiver System for In-Probe 3-D Ultrasonic Imaging.

PubMed

Attarzadeh, Hourieh; Xu, Ye; Ytterdal, Trond

2017-10-01

In this paper, a dual-mode low-power, high dynamic-range receiver circuit is designed for the interface with a capacitive micromachined ultrasonic transducer. The proposed ultrasound receiver chip enables the development of an in-probe digital beamforming imaging system. The flexibility of having two operation modes offers a high dynamic range with minimum power sacrifice. A prototype of the chip containing one receive channel, with one variable transimpedance amplifier (TIA) and one analog to digital converter (ADC) circuit is implemented. Combining variable gain TIA functionality with ADC gain settings achieves an enhanced overall high dynamic range, while low power dissipation is maintained. The chip is designed and fabricated in a 65 nm standard CMOS process technology. The test chip occupies an area of 76[Formula: see text] 170 [Formula: see text]. A total average power range of 60-240 [Formula: see text] for a sampling frequency of 30 MHz, and a center frequency of 5 MHz is measured. An instantaneous dynamic range of 50.5 dB with an overall dynamic range of 72 dB is obtained from the receiver circuit.

Energy efficiency analysis of two-sided feed scheme of DC traction network with high asymmetry of feeders parameters

NASA Astrophysics Data System (ADS)

Abramov, E. Y.; Sopov, V. I.

2017-10-01

In a given research using the example of traction network area with high asymmetry of power supply parameters, the sequence of comparative assessment of power losses in DC traction network with parallel and traditional separated operating modes of traction substation feeders was shown. Experimental measurements were carried out under these modes of operation. The calculation data results based on statistic processing showed the power losses decrease in contact network and the increase in feeders. The changes proved to be critical ones and this demonstrates the significance of potential effects when converting traction network areas into parallel feeder operation. An analytical method of calculation the average power losses for different feed schemes of the traction network was developed. On its basis, the dependences of the relative losses were obtained by varying the difference in feeder voltages. The calculation results showed unreasonableness transition to a two-sided feed scheme for the considered traction network area. A larger reduction in the total power loss can be obtained with a smaller difference of the feeders’ resistance and / or a more symmetrical sectioning scheme of contact network.

Energy efficient lighting and communications

NASA Astrophysics Data System (ADS)

Zhou, Z.; Kavehrad, M.; Deng, P.

2012-01-01

As Light-Emitting Diode (LED)'s increasingly displace incandescent lighting over the next few years, general applications of Visible Light Communication (VLC) technology are expected to include wireless internet access, vehicle-to-vehicle communications, broadcast from LED signage, and machine-to-machine communications. An objective in this paper is to reveal the influence of system parameters on the power distribution and communication quality, in a general plural sources VLC system. It is demonstrated that sources' Half-Power Angles (HPA), receivers' Field-Of Views (FOV), sources layout and the power distribution among sources are significant impact factors. Based on our findings, we developed a method to adaptively change working status of each LED respectively according to users' locations. The program minimizes total power emitted while simultaneously ensuring sufficient light intensity and communication quality for each user. The paper also compares Orthogonal Frequency-Division Multiplexing (OFDM) and On-Off Keying (OOK) signals performance in indoor optical wireless communications. The simulation is carried out for different locations where different impulse response distortions are experienced. OFDM seems a better choice than prevalent OOK for indoor VLC due to its high resistance to multi-path effect and delay spread. However, the peak-to-average power limitations of the method must be investigated for lighting LEDs.

Using radiative energy losses to constrain the magnetization and magnetic reconnection rate at the base of black hole jets

NASA Astrophysics Data System (ADS)

Potter, William J.

2017-02-01

We calculate the severe radiative energy losses which occur at the base of black hole jets using a relativistic fluid jet model, including in situ acceleration of non-thermal leptons by magnetic reconnection. Our results demonstrate that including a self-consistent treatment of radiative energy losses is necessary to perform accurate magnetohydrodynamic simulations of powerful jets and that jet spectra calculated via post-processing are liable to vastly overestimate the amount of non-thermal emission. If no more than 95 per cent of the initial total jet power is radiated away by the plasma travels as it travels along the length of the jet, we can place a lower bound on the magnetization of the jet plasma at the base of the jet. For typical powerful jets, we find that the plasma at the jet base is required to be highly magnetized, with at least 10 000 times more energy contained in magnetic fields than in non-thermal leptons. Using a simple power-law model of magnetic reconnection, motivated by simulations of collisionless reconnection, we determine the allowed range of the large-scale average reconnection rate along the jet, by restricting the total radiative energy losses incurred and the distance at which the jet first comes into equipartition. We calculate analytic expressions for the cumulative radiative energy losses due to synchrotron and inverse-Compton emission along jets, and derive analytic formulae for the constraint on the initial magnetization.

Reliability of quantitative EEG (qEEG) measures and LORETA current source density at 30 days.

PubMed

Cannon, Rex L; Baldwin, Debora R; Shaw, Tiffany L; Diloreto, Dominic J; Phillips, Sherman M; Scruggs, Annie M; Riehl, Timothy C

2012-06-14

There is a growing interest for using quantitative EEG and LORETA current source density in clinical and research settings. Importantly, if these indices are to be employed in clinical settings then the reliability of these measures is of great concern. Neuroguide (Applied Neurosciences) is sophisticated software developed for the analyses of power, and connectivity measures of the EEG as well as LORETA current source density. To date there are relatively few data evaluating topographical EEG reliability contrasts for all 19 channels and no studies have evaluated reliability for LORETA calculations. We obtained 4 min eyes-closed and eyes-opened EEG recordings at 30-day intervals. The EEG was analyzed in Neuroguide and FFT power, coherence and phase was computed for traditional frequency bands (delta, theta, alpha and beta) and LORETA current source density was calculated in 1 Hz increments and summed for total power in eight regions of interest (ROI). In order to obtain a robust measure of reliability we utilized a random effects model with an absolute agreement definition. The results show very good reproducibility for total absolute power and coherence. Phase shows lower reliability coefficients. LORETA current source density shows very good reliability with an average 0.81 for ECB and 0.82 for EOB. Similarly, the eight regions of interest show good to very good agreement across time. Implications for future directions and use of qEEG and LORETA in clinical populations are discussed. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Reduction of dissipation in a thermal engine by means of periodic changes of external constraintsa)

NASA Astrophysics Data System (ADS)

Escher, Claus; Ross, John

1985-03-01

We consider a thermal engine driven by chemical reactions, which take place in a continuous flow, stirred tank reactor fitted with a movable piston. Work can be produced by means of a heat engine coupled to the products and to an external heat bath, and by the piston. Two modes of operation are compared, each with fixed input rate of chemicals: one with periodic variation of an external constraint [mode (b)], in which we vary the external pressure, and one without such variation [mode (a)]. We derive equations for the total power output in each of the two modes. The power output in mode (b) can be larger than that of mode (a) for the same chemical throughput and for the same average value of the external pressure. For a particularly simple case it is shown that the total power output in mode (b) is larger than that in (a) if work is done by the piston. At the same time the entropy production is decreased and the efficiency is increased. The possibility of an increased power output is due to the proper control of the relative phase of the externally varied constraint and its conjugate variable, the external pressure and the volume. This control is achieved by the coupling of nonlinear kinetics to the externally varied constraint. Details of specific mechanisms and the occurrence of resonance phenomena are presented in the following article.

Experimental study on parasitic mode suppression using FeSiAl in relativistic klystron amplifier

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

Zhang, Zehai

2015-03-15

Experimental study of parasitic mode suppression using electromagnetic attenuate material FeSiAl in an S-band Relativistic Klystron Amplifier (RKA) is presented in this paper. The FeSiAl powder is coated and sintered onto the inner surface of a drift tube which locates between the input and the middle cavity of the RKA. Cold tests show that the attenuate rate of the tube against parasitic mode TE{sub 11} is about 50%. Experiments carried out on the Torch-01 accelerator present that the tube is effective in suppressing the parasitic mode. Two typical outputs are obtained. When the diode voltage is on a moderate level,more » the RKA operates well and the parasitic mode is totally suppressed. The pulse length of the High Power Microwave (HPM) almost equals the electron beam pulse length and the HPM average output power is about 300 MW, with a power efficiency of 10%. When the diode voltage is on a higher level, the output power and efficiency rise but the parasitic mode oscillation occurred and the pulse length is shortened. By contrast, the parasitic mode oscillation is too strong for the RKA to operate normally with un-sintered drift tube. The experimental study implies that FeSiAl is effective in suppressing the parasitic mode oscillation in a certain extent. However, total suppression needs a deeper attenuate rate and further investigation.« less

Universities Scale Like Cities

PubMed Central

van Raan, Anthony F. J.

2013-01-01

Recent studies of urban scaling show that important socioeconomic city characteristics such as wealth and innovation capacity exhibit a nonlinear, particularly a power law scaling with population size. These nonlinear effects are common to all cities, with similar power law exponents. These findings mean that the larger the city, the more disproportionally they are places of wealth and innovation. Local properties of cities cause a deviation from the expected behavior as predicted by the power law scaling. In this paper we demonstrate that universities show a similar behavior as cities in the distribution of the ‘gross university income’ in terms of total number of citations over ‘size’ in terms of total number of publications. Moreover, the power law exponents for university scaling are comparable to those for urban scaling. We find that deviations from the expected behavior can indeed be explained by specific local properties of universities, particularly the field-specific composition of a university, and its quality in terms of field-normalized citation impact. By studying both the set of the 500 largest universities worldwide and a specific subset of these 500 universities -the top-100 European universities- we are also able to distinguish between properties of universities with as well as without selection of one specific local property, the quality of a university in terms of its average field-normalized citation impact. It also reveals an interesting observation concerning the working of a crucial property in networked systems, preferential attachment. PMID:23544062

Heuristic approaches for energy-efficient shared restoration in WDM networks

NASA Astrophysics Data System (ADS)

Alilou, Shahab

In recent years, there has been ongoing research on the design of energy-efficient Wavelength Division Multiplexing (WDM) networks. The explosive growth of Internet traffic has led to increased power consumption of network components. Network survivability has also been a relevant research topic, as it plays a crucial role in assuring continuity of service with no disruption, regardless of network component failure. Network survivability mechanisms tend to utilize considerable resources such as spare capacity in order to protect and restore information. This thesis investigates techniques for reducing energy demand and enhancing energy efficiency in the context of network survivability. We propose two novel heuristic energy-efficient shared protection approaches for WDM networks. These approaches intend to save energy by setting on sleep mode devices that are not being used while providing shared backup paths to satisfy network survivability. The first approach exploits properties of a math series in order to assign weight to the network links. It aims at reducing power consumption at the network indirectly by aggregating traffic on a set of nodes and links with high traffic load level. Routing traffic on links and nodes that are already under utilization makes it possible for the links and nodes with no load to be set on sleep mode. The second approach is intended to dynamically route traffic through nodes and links with high traffic load level. Similar to the first approach, this approach computes a pair of paths for every newly arrived demand. It computes these paths for every new demand by comparing the power consumption of nodes and links in the network before the demand arrives with their potential power consumption if they are chosen along the paths of this demand. Simulations of two different networks were used to compare the total network power consumption obtained using the proposed techniques against a standard shared-path restoration scheme. Shared-path restoration is a network survivability method in which a link-disjoint backup path and wavelength is reserved at the time of call setup for a working path. However, in order to reduce spare capacity consumption, this reserved backup path and wavelength may be shared with other backup paths. Pool Sharing Scheme (PSS) is employed to implement shared-path restoration scheme [1]. In an optical network, the failure of a single link leads to the failure of all the lightpaths that pass through that particular link. PSS ensures that the amount of backup bandwidth required on a link to restore the failed connections will not be more than the total amount of reserved backup bandwidth on that link. Simulation results indicate that the proposed approaches lead to up to 35% power savings in WDM networks when traffic load is low. However, power saving decreases to 14% at high traffic load level. Furthermore, in terms of the total capacity consumption for working paths, PSS outperforms the two proposed approaches, as expected. In terms of total capacity consumption all the approaches behave similarly. In general, at low traffic load level, the two proposed approaches behave similar to PSS in terms of average link load, and the ratio of block demands. Nevertheless, at high traffic load, the proposed approaches result in higher ratio of blocked demands than PSS. They also lead to higher average link load than PSS for the equal number of generated demands.

Stochastic Growth Theory of Spatially-Averaged Distributions of Langmuir Fields in Earth's Foreshock

NASA Technical Reports Server (NTRS)

Boshuizen, Christopher R.; Cairns, Iver H.; Robinson, P. A.

2001-01-01

Langmuir-like waves in the foreshock of Earth are characteristically bursty and irregular, and are the subject of a number of recent studies. Averaged over the foreshock, it is observed that the probability distribution is power-law P(bar)(log E) in the wave field E with the bar denoting this averaging over position, In this paper it is shown that stochastic growth theory (SGT) can explain a power-law spatially-averaged distributions P(bar)(log E), when the observed power-law variations of the mean and standard deviation of log E with position are combined with the log normal statistics predicted by SGT at each location.

Simulations of thermal lensing of a Ti:Sapphire crystal end-pumped with high average power

NASA Astrophysics Data System (ADS)

Wagner, Gerd; Shiler, Max; Wulfmeyer, Volker

2005-10-01

A detailed 3-dimensional calculation of the temperature field of a laser crystal pumped with high average power is presented. The pump configuration, the anisotropy of a Brewster-angle-cut Ti:Sapphire crystal, and the temperature dependence of the thermal conductivity are taken into account. The corresponding focal length of the thermal lens is calculated for pump levels up to 100 W. This refined thermal model is the basis for a optimized resonator design of a high-average power differential absorption lidar system transmitter.

Simulations of thermal lensing of a Ti:Sapphire crystal end-pumped with high average power.

PubMed

Wagner, Gerd; Shiler, Max; Wulfmeyer, Volker

2005-10-03

A detailed 3-dimensional calculation of the temperature field of a laser crystal pumped with high average power is presented. The pump configuration, the anisotropy of a Brewster-angle-cut Ti:Sapphire crystal, and the temperature dependence of the thermal conductivity are taken into account. The corresponding focal length of the thermal lens is calculated for pump levels up to 100 W. This refined thermal model is the basis for a optimized resonator design of a high-average power differential absorption lidar system transmitter.

Implications of the experimental results on high energy cosmic rays with regard to their origin

NASA Technical Reports Server (NTRS)

Fichtel, C. E.; Linsley, J.

1985-01-01

It was shown in an earlier report that current cosmic ray evidence supports a change in the cosmic ray composition in the region between 10 to the 6th power and 10 to the 8th power GeV total energy in the direction of a smaller average value of A. Compared to normal celestial abundances, the heavy nuclei are much less abundant, and, in fact, the composition measurements above 10 to the 8th power GeV are consistent with there being only protons. Here, these results combined with those of the energy spectrum and anisotropy of the comsic rays and other astrophysical information will be examined to try to determine their implications for the origin of the cosmic rays. In this paper, consideration is given to the implications of one or more than one type of source in the galaxy to see which are consistent with the interpretation of current measurements. The nature of the source types that would be required are discussed.

Spatially confined low-power optically pumped ultrafast synchrotron x-ray nanodiffraction

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

Park, Joonkyu; Zhang, Qingteng; Chen, Pice

2015-08-27

The combination of ultrafast optical excitation and time-resolved synchrotron x-ray nanodiffraction provides unique insight into the photoinduced dynamics of materials, with the spatial resolution required to probe individual nanostructures or small volumes within heterogeneous materials. Optically excited x-ray nanobeam experiments are challenging because the high total optical power required for experimentally relevant optical fluences leads to mechanical instability due to heating. For a given fluence, tightly focusing the optical excitation reduces the average optical power by more than three orders of magnitude and thus ensures sufficient thermal stability for x-ray nanobeam studies. Delivering optical pulses via a scannable fiber-coupled opticalmore » objective provides a well-defined excitation geometry during rotation and translation of the sample and allows the selective excitation of isolated areas within the sample. Finally, experimental studies of the photoinduced lattice dynamics of a 35 nm BiFeO 3 thin film on a SrTiO 3 substrate demonstrate the potential to excite and probe nanoscale volumes.« less

Wind power as an electrical energy source in Illinois

NASA Astrophysics Data System (ADS)

Wendland, W. M.

1982-03-01

A preliminary estimate of the total wind power available in Illinois was made using available historical data, and projections of cost savings due to the presence of wind-generated electricity were attempted. Wind data at 10 m height were considered from nine different sites in the state, with three years data nominally being included. Wind-speed frequency histograms were developed for day and night periods, using a power law function to extrapolate the 10 m readings to 20 m. Wind speeds over the whole state were found to average over 8 mph, the cut-in point for most wind turbines, for from 40-63% of the time. A maximum of 75% run-time was determined for daylight hours in April-May. A reference 1.8 kW windpowered generator was used in annual demand projections for a reference one family home, using the frequency histograms. The small generator was projected to fulfill from 25-53% of the annual load, and, based on various cost assumptions, exhibited paybacks taking from 14-27 yr.

Simulation and Evaluation of Small Scale Solar Power Tower Performance under Malaysia Weather Conditions

NASA Astrophysics Data System (ADS)

Gamil, A. M.; Gilani, S. I.; Al-Kayiem, H. H.

2013-06-01

Solar energy is the most available, clean, and inexpensive source of energy among the other renewable sources of energy. Malaysia is an encouraging location for the development of solar energy systems due to abundant sunshine (10 hours daily with average solar energy received between 1400 and 1900 kWh/m2). In this paper the design of heliostat field of 3 dual-axis heliostat units located in Ipoh, Malaysia is introduced. A mathematical model was developed to estimate the sun position and calculate the cosine losses in the field. The study includes calculating the incident solar power to a fixed target on the tower by analysing the tower height and ground distance between the heliostat and the tower base. The cosine efficiency was found for each heliostat according to the sun movement. TRNSYS software was used to simulate the cosine efficiencies and field hourly incident solar power input to the fixed target. The results show the heliostat field parameters and the total incident solar input to the receiver.

Potential sources of precipitation in Lake Baikal basin

NASA Astrophysics Data System (ADS)

Shukurov, K. A.; Mokhov, I. I.

2017-11-01

Based on the data of long-term measurements at 23 meteorological stations in the Russian part of the Lake Baikal basin the probabilities of daily precipitation with different intensity and their contribution to the total precipitation are estimated. Using the trajectory model HYSPLIT_4 for each meteorological station for the period 1948-2016 the 10-day backward trajectories of air parcels, the height of these trajectories and distribution of specific humidity along the trajectories are calculated. The average field of power of potential sources of daily precipitation (less than 10 mm) for all meteorological stations in the Russian part of the Lake Baikal basin was obtained using the CWT (concentration weighted trajectory) method. The areas have been identified from which within 10 days water vapor can be transported to the Lake Baikal basin, as well as regions of the most and least powerful potential sources. The fields of the mean height of air parcels trajectories and the mean specific humidity along the trajectories are compared with the field of mean power of potential sources.

Evaluation of performance of select fusion experiments and projected reactors

NASA Technical Reports Server (NTRS)

Miley, G. H.

1978-01-01

The performance of NASA Lewis fusion experiments (SUMMA and Bumpy Torus) is compared with other experiments and that necessary for a power reactor. Key parameters cited are gain (fusion power/input power) and the time average fusion power, both of which may be more significant for real fusion reactors than the commonly used Lawson parameter. The NASA devices are over 10 orders of magnitude below the required powerplant values in both gain and time average power. The best experiments elsewhere are also as much as 4 to 5 orders of magnitude low. However, the NASA experiments compare favorably with other alternate approaches that have received less funding than the mainline experiments. The steady-state character and efficiency of plasma heating are strong advantages of the NASA approach. The problem, though, is to move ahead to experiments of sufficient size to advance in gain and average power parameters.

Watt-level passively Q-switched heavily Er3+-doped ZBLAN fiber laser with a semiconductor saturable absorber mirror

PubMed Central

Shen, Yanlong; Wang, Yishan; Luan, Kunpeng; Huang, Ke; Tao, Mengmeng; Chen, Hongwei; Yi, Aiping; Feng, Guobin; Si, Jinhai

2016-01-01

A diode-cladding pumped mid-infrared passively Q-switched Er3+-doped ZBLAN fiber laser with an average output power of watt-level based on a semiconductor saturable absorber mirror (SESAM) is demonstrated. Stable pulse train was produced at a slope efficiency of 17.8% with respect to launched pump power. The maximum average power of 1.01 W at a repetition rate of 146.3 kHz was achieved with a corresponding pulse energy of 6.9 μJ, from which the maximum peak power was calculated to be 21.9 W. To the best of our knowledge, the average power and the peak power are the highest in 3 μm region passively Q-switched fiber lasers. The influence of gain fiber length on the operation regime of the fiber laser has been investigated in detail. PMID:27225029

New constraints on modelling the random magnetic field of the MW

NASA Astrophysics Data System (ADS)

Beck, Marcus C.; Beck, Alexander M.; Beck, Rainer; Dolag, Klaus; Strong, Andrew W.; Nielaba, Peter

2016-05-01

We extend the description of the isotropic and anisotropic random component of the small-scale magnetic field within the existing magnetic field model of the Milky Way from Jansson & Farrar, by including random realizations of the small-scale component. Using a magnetic-field power spectrum with Gaussian random fields, the NE2001 model for the thermal electrons and the Galactic cosmic-ray electron distribution from the current GALPROP model we derive full-sky maps for the total and polarized synchrotron intensity as well as the Faraday rotation-measure distribution. While previous work assumed that small-scale fluctuations average out along the line-of-sight or which only computed ensemble averages of random fields, we show that these fluctuations need to be carefully taken into account. Comparing with observational data we obtain not only good agreement with 408 MHz total and WMAP7 22 GHz polarized intensity emission maps, but also an improved agreement with Galactic foreground rotation-measure maps and power spectra, whose amplitude and shape strongly depend on the parameters of the random field. We demonstrate that a correlation length of 0≈22 pc (05 pc being a 5σ lower limit) is needed to match the slope of the observed power spectrum of Galactic foreground rotation-measure maps. Using multiple realizations allows us also to infer errors on individual observables. We find that previously-used amplitudes for random and anisotropic random magnetic field components need to be rescaled by factors of ≈0.3 and 0.6 to account for the new small-scale contributions. Our model predicts a rotation measure of -2.8±7.1 rad/m2 and 04.4±11. rad/m2 for the north and south Galactic poles respectively, in good agreement with observations. Applying our model to deflections of ultra-high-energy cosmic rays we infer a mean deflection of ≈3.5±1.1 degree for 60 EeV protons arriving from CenA.

Aerosol particles generated by diesel-powered school buses at urban schools as a source of children’s exposure

PubMed Central

Hochstetler, Heather A.; Yermakov, Mikhail; Reponen, Tiina; Ryan, Patrick H.; Grinshpun, Sergey A.

2015-01-01

Various heath effects in children have been associated with exposure to traffic-related particulate matter (PM), including emissions from school buses. In this study, the indoor and outdoor aerosol at four urban elementary schools serviced by diesel-powered school buses was characterized with respect to the particle number concentrations and size distributions as well as the PM2.5 mass concentrations and elemental compositions. It was determined that the presence of school buses significantly affected the outdoor particle size distribution, specifically in the ultrafine fraction. The time-weighted average of the total number concentration measured outside the schools was significantly associated with the bus and the car counts. The concentration increase was consistently observed during the morning drop-off hours and in most of the days during the afternoon pick-up period (although at a lower degree). Outdoor PM2.5 mass concentrations measured at schools ranged from 3.8 to 27.6 µg m−3. The school with the highest number of operating buses exhibited the highest average PM2.5 mass concentration. The outdoor mass concentrations of elemental carbon (EC) and organic carbon (OC) were also highest at the school with the greatest number of buses. Most (47/55) correlations between traffic-related elements identified in the outdoor PM2.5 were significant with elements identified in the indoor PM2.5. Significant associations were observed between indoor and outdoor aerosols for EC, EC/OC, and the total particle number concentration. Day-to-day and school-to-school variations in Indoor/Outdoor (I/O) ratios were related to the observed differences in opening windows and doors, which enhanced the particle penetration, as well as indoor activities at schools. Overall, the results on I/O ratio obtained in this study reflect the sizes of particles emitted by diesel-powered school bus engines (primarily, an ultrafine fraction capable of penetrating indoors). PMID:25904818

Aerosol particles generated by diesel-powered school buses at urban schools as a source of children's exposure

NASA Astrophysics Data System (ADS)

Hochstetler, Heather A.; Yermakov, Mikhail; Reponen, Tiina; Ryan, Patrick H.; Grinshpun, Sergey A.

2011-03-01

Various heath effects in children have been associated with exposure to traffic-related particulate matter (PM), including emissions from school buses. In this study, the indoor and outdoor aerosol at four urban elementary schools serviced by diesel-powered school buses was characterized with respect to the particle number concentrations and size distributions as well as the PM2.5 mass concentrations and elemental compositions. It was determined that the presence of school buses significantly affected the outdoor particle size distribution, specifically in the ultrafine fraction. The time-weighted average of the total number concentration measured outside the schools was significantly associated with the bus and the car counts. The concentration increase was consistently observed during the morning drop-off hours and in most of the days during the afternoon pick-up period (although at a lower degree). Outdoor PM2.5 mass concentrations measured at schools ranged from 3.8 to 27.6 μg m-3. The school with the highest number of operating buses exhibited the highest average PM2.5 mass concentration. The outdoor mass concentrations of elemental carbon (EC) and organic carbon (OC) were also highest at the school with the greatest number of buses. Most (47/55) correlations between traffic-related elements identified in the outdoor PM2.5 were significant with elements identified in the indoor PM2.5. Significant associations were observed between indoor and outdoor aerosols for EC, EC/OC, and the total particle number concentration. Day-to-day and school-to-school variations in Indoor/Outdoor (I/O) ratios were related to the observed differences in opening windows and doors, which enhanced the particle penetration, as well as indoor activities at schools. Overall, the results on I/O ratio obtained in this study reflect the sizes of particles emitted by diesel-powered school bus engines (primarily, an ultrafine fraction capable of penetrating indoors).

Aerosol particles generated by diesel-powered school buses at urban schools as a source of children's exposure.

PubMed

Hochstetler, Heather A; Yermakov, Mikhail; Reponen, Tiina; Ryan, Patrick H; Grinshpun, Sergey A

2011-03-01

Various heath effects in children have been associated with exposure to traffic-related particulate matter (PM), including emissions from school buses. In this study, the indoor and outdoor aerosol at four urban elementary schools serviced by diesel-powered school buses was characterized with respect to the particle number concentrations and size distributions as well as the PM2.5 mass concentrations and elemental compositions. It was determined that the presence of school buses significantly affected the outdoor particle size distribution, specifically in the ultrafine fraction. The time-weighted average of the total number concentration measured outside the schools was significantly associated with the bus and the car counts. The concentration increase was consistently observed during the morning drop-off hours and in most of the days during the afternoon pick-up period (although at a lower degree). Outdoor PM2.5 mass concentrations measured at schools ranged from 3.8 to 27.6 µg m -3 . The school with the highest number of operating buses exhibited the highest average PM2.5 mass concentration. The outdoor mass concentrations of elemental carbon (EC) and organic carbon (OC) were also highest at the school with the greatest number of buses. Most (47/55) correlations between traffic-related elements identified in the outdoor PM2.5 were significant with elements identified in the indoor PM2.5. Significant associations were observed between indoor and outdoor aerosols for EC, EC/OC, and the total particle number concentration. Day-to-day and school-to-school variations in Indoor/Outdoor (I/O) ratios were related to the observed differences in opening windows and doors, which enhanced the particle penetration, as well as indoor activities at schools. Overall, the results on I/O ratio obtained in this study reflect the sizes of particles emitted by diesel-powered school bus engines (primarily, an ultrafine fraction capable of penetrating indoors).

Mode-locked Yb:YAG thin-disk oscillator with 41 µJ pulse energy at 145 W average infrared power and high power frequency conversion.

PubMed

Bauer, Dominik; Zawischa, Ivo; Sutter, Dirk H; Killi, Alexander; Dekorsy, Thomas

2012-04-23

We demonstrate the generation of 1.1 ps pulses containing more than 41 µJ of energy directly out of an Yb:YAG thin-disk without any additional amplification stages. The laser oscillator operates in ambient atmosphere with a 3.5 MHz repetition rate and 145 W of average output power at a fundamental wavelength of 1030 nm. An average output power of 91.5 W at 515 nm was obtained by frequency doubling with a conversion efficiency exceeding 65%. Third harmonic generation resulted in 34 W at 343 nm at 34% efficiency. © 2012 Optical Society of America

New type of transformerless high efficiency inverter

NASA Astrophysics Data System (ADS)

Naaijer, G. J.

Inverter architectures are presented which allow economical ac/dc switching for solar cell array and battery power use in domestic and industrial applications. The efficiencies of currently available inverters are examined and compared with a new 2.2 kW transformerless stepped wave inverter. The inverter has low no-load losses, amounting to 200 Wh/24 hr, and features voltage steps occurring 15-30 times/sine wave period. An example is provided for an array/battery/inverter assembly with the inverter control electronics activating or disconnecting the battery subassemblies based on the total number of activated subassemblies in relation to a reference sinewave, and the need to average the battery subassembly discharge rates. A total harmonic distortion of 6 percent was observed, and the system is noted to be usable as a battery charger.

Increase in NOx emissions from Indian thermal power plants during 1996-2010: unit-based inventories and multisatellite observations.

PubMed

Lu, Zifeng; Streets, David G

2012-07-17

Driven by rapid economic development and growing electricity demand, NO(x) emissions (E) from the power sector in India have increased dramatically since the mid-1990s. In this study, we present the NO(x) emissions from Indian public thermal power plants for the period 1996-2010 using a unit-based methodology and compare the emission estimates with the satellite observations of NO(2) tropospheric vertical column densities (TVCDs) from four spaceborne instruments: GOME, SCIAMACHY, OMI, and GOME-2. Results show that NO(x) emissions from Indian power plants increased by at least 70% during 1996-2010. Coal-fired power plants, NO(x) emissions from which are not regulated in India, contribute ∼96% to the total power sector emissions, followed by gas-fired (∼4%) and oil-fired (<1%) ones. A number of isolated NO(2) hot spots are observed over the power plant areas, and good agreement between NO(2) TVCDs and NO(x) emissions is found for areas dominated by power plant emissions. Average NO(2) TVCDs over power plant areas were continuously increasing during the study period. We find that the ratio of ΔE/E to ΔTVCD/TVCD changed from greater than one to less than one around 2005-2008, implying that a transition of the overall NO(x) chemistry occurred over the power plant areas, which may cause significant impact on the atmospheric environment.

Total and methyl mercury contents and distribution characteristics in cicada, Cryptotympana atrata (Fabricius).

PubMed

Zheng, Dongmei; Zhang, Zhongsheng; Wang, Qichao

2010-06-01

Total and methyl mercury concentrations of cicada bodies, wings, and exuviae were investigated to study the mercury distribution characteristics. Results indicated that total and methyl mercury concentrations of cicada bodies were 2.64 mg/kg and 123.93 ng/g on average, respectively. In cicada tissues, total mercury concentrations were found to increase in the order of exuviae (0.50 mg/kg on average) < wings (0.98 mg/kg on average) < cicada bodies (2.64 mg/kg on average) and methyl mercury concentrations of cicada bodies were 123.93 ng/g on average and were the highest. Methyl mercury concentrations accounted for about 4.69% of total mercury in cicada bodies and most mercury was in inorganic forms in cicada. Sex differences of total mercury concentrations were significantly great (F = 8.433, p < 0.01) and total mercury concentrations of the males, which were 3.38 mg/kg on average, were much higher. Correlation analysis showed that neither total nor methyl mercury concentrations of cicada bodies was significantly related to the corresponding contents of soil (r = 0.0598, p > 0.05).

Contact lens overrefraction variability in corneal power estimation after refractive surgery.

PubMed

Joslin, Charlotte E; Koster, James; Tu, Elmer Y

2005-12-01

To evaluate the accuracy and precision of the contact lens overrefraction (CLO) method in determining corneal refractive power in post-refractive-surgery eyes. Refractive Surgery Service and Contact Lens Service, University of Illinois, Chicago, Illinois, USA. Fourteen eyes of 7 subjects who had a single myopic laser in situ keratomileusis procedure within 12 months with refractive stability were included in this prospective case series. The CLO method was compared with the historical method of predicting the corneal power using 4 different lens fitting strategies and 3 refractive pupil scan sizes (3 mm, 5 mm, and total pupil). Rigid lenses included 3 9.0 mm overall diameter lenses fit flat, steep, and an average of the 2, and a 15.0 mm diameter lens steep fit. Cycloplegic CLO was performed using the autorefractor function of the Nidek OPD-Scan ARK-10000. Results with each strategy were compared with the corneal power estimated with the historical method. The bias (mean of the difference), 95% limits of agreement, and difference versus mean plots for each strategy are presented. In each subject, the CLO-estimated corneal power varied based on lens fit. On average, the bias between CLO and historical methods ranged from -0.38 to +2.42 diopters (D) and was significantly different from 0 in all but 3 strategies. Substantial variability in precision existed between fitting strategies, with the range of the 95% limits of agreement approximating 0.50 D in 2 strategies and 2.59 D in the worst-case scenario. The least precise fitting strategy was use of flat-fitting 9.0 mm diameter lenses. The accuracy and precision of the CLO method of estimating corneal power in post-refractive-surgery eyes was highly variable on the basis of how rigid lense were fit. One of the most commonly used fitting strategies in clinical practice--flat-fitting a 9.0 diameter lens-resulted in the poorest accuracy and precision. Results also suggest use of large-diameter lenses may improve outcomes.

TEP Power Partners Project [Tucson Electric Power

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

None, None

2014-02-06

The Arizona Governor’s Office of Energy Policy, in partnership with Tucson Electric Power (TEP), Tendril, and Next Phase Energy (NPE), formed the TEP Power Partners pilot project to demonstrate how residential customers could access their energy usage data and third party applications using data obtained from an Automatic Meter Reading (AMR) network. The project applied for and was awarded a Smart Grid Data Access grant through the U.S. Department of Energy. The project participants’ goal for Phase I is to actively engage 1,700 residential customers to demonstrate sustained participation, reduction in energy usage (kWh) and cost ($), and measure relatedmore » aspects of customer satisfaction. This Demonstration report presents a summary of the findings, effectiveness, and customer satisfaction with the 15-month TEP Power Partners pilot project. The objective of the program is to provide residential customers with energy consumption data from AMR metering and empower these participants to better manage their electricity use. The pilot recruitment goals included migrating 700 existing customers from the completed Power Partners Demand Response Load Control Project (DRLC), and enrolling 1,000 new participants. Upon conclusion of the project on November 19, 2013; 1,390 Home Area Networks (HANs) were registered; 797 new participants installed a HAN; Survey respondents’ are satisfied with the program and found value with a variety of specific program components; Survey respondents report feeling greater control over their energy usage and report taking energy savings actions in their homes after participating in the program; On average, 43 % of the participants returned to the web portal monthly and 15% returned weekly; and An impact evaluation was completed by Opinion Dynamics and found average participant savings for the treatment period1 to be 2.3% of their household use during this period.2 In total, the program saved 163 MWh in the treatment period of 2013.« less

Mutation rate estimation for 15 autosomal STR loci in a large population from Mainland China.

PubMed

Zhao, Zhuo; Zhang, Jie; Wang, Hua; Liu, Zhi-Peng; Liu, Ming; Zhang, Yuan; Sun, Li; Zhang, Hui

2015-09-01

STR, short tandem repeats, are well known as a type of powerful genetic marker and widely used in studying human population genetics. Compared with the conventional genetic markers, the mutation rate of STR is higher. Additionally, the mutations of STR loci do not lead to genetic inconsistencies between the genotypes of parents and children; therefore, the analysis of STR mutation is more suited to assess the population mutation. In this study, we focused on 15 autosomal STR loci. DNA samples from a total of 42,416 unrelated healthy individuals (19,037 trios) from the population of Mainland China collected between Jan 2012 and May 2014 were successfully investigated. In our study, the allele frequencies, paternal mutation rates, maternal mutation rates and average mutation rates were detected. Furthermore, we also investigated the relationship between paternal ages, maternal ages, area, the time of pregnancy and average mutation rate. We found that the paternal mutation rate was higher than the maternal mutation rate and the paternal, maternal, and average mutation rates had a positive correlation with paternal age, maternal age and the time of pregnancy respectively. Additionally, the average mutation rate of coastal areas was higher than that of inland areas.

High density culture of white bass X striped bass fingerlings in raceways using power plant heated effluent

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

Collins, C.M.; Burton, G.L.; Schweinforth, R.L.

1983-06-01

White bass (Morone chrysops) X striped bass (M. saxatilis) hybrids weighing 1691/lb were initially stocked in five 24 ft/sup 3/ floating screen cages for 20 days. Hybrids averaging one inch in total length and 361 fish/lb were released in four 614 ft/sup 3/ concrete raceways. Two stocking densities, 2.6 and 5.1 fish/ft/sup 3/, were evaluated in the 94-day study using a flow rate of 300 gpm/raceway. Water temperatures averaged 79/sup 0/F and water quality was adequate throughout the production period. Fish were hand fed to satiation daily. Columnaris and Aeromonas hydrophila caused the most serious disease problems. Gas supersaturation wasmore » suspect in high mortality levels during cage culture of hybrid bass fry. Cannibalism may have been responsible for unaccountable losses prior to raceway stocking and at harvest. The study yielded 5773 hybrids weighing 658 lb. The high density treatment showed greater weight gain, average weight, average length and percent survival as well as improved food conversion. Results suggest that higher stocking densities and periodic grading may increase production and suppress cannibalism. 10 references, 3 figures, 3 tables.« less

Precision cosmology with baryons: non-radiative hydrodynamics of galaxy groups

NASA Astrophysics Data System (ADS)

Rabold, Manuel; Teyssier, Romain

2017-05-01

The effect of baryons on the matter power spectrum is likely to have an observable effect for future galaxy surveys, like Euclid or Large Synoptic Survey Telescope (LSST). As a first step towards a fully predictive theory, we investigate the effect of non-radiative hydrodynamics on the structure of galaxy groups sized haloes, which contribute the most to the weak-lensing power spectrum. We perform high-resolution (more than one million particles per halo and one kilo-parsec resolution) non-radiative hydrodynamical zoom-in simulations of a sample of 16 haloes, comparing the profiles to popular analytical models. We find that the total mass profile is well fitted by a Navarro, Frenk & White model, with parameters slightly modified from the dark matter only simulation. We also find that the Komatsu & Seljak hydrostatic solution provides a good fit to the gas profiles, with however significant deviations, arising from strong turbulent mixing in the core and from non-thermal, turbulent pressure support in the outskirts. The turbulent energy follows a shallow, rising linear profile with radius, and correlates with the halo formation time. Using only three main structural halo parameters as variables (total mass, concentration parameter and central gas density), we can predict, with an accuracy better than 20 per cent, the individual gas density and temperature profiles. For the average total mass profile, which is relevant for power spectrum calculations, we even reach an accuracy of 1 per cent. The robustness of these predictions has been tested against resolution effects, different types of initial conditions and hydrodynamical schemes.

On the averaging area for incident power density for human exposure limits at frequencies over 6 GHz

NASA Astrophysics Data System (ADS)

Hashimoto, Yota; Hirata, Akimasa; Morimoto, Ryota; Aonuma, Shinta; Laakso, Ilkka; Jokela, Kari; Foster, Kenneth R.

2017-04-01

Incident power density is used as the dosimetric quantity to specify the restrictions on human exposure to electromagnetic fields at frequencies above 3 or 10 GHz in order to prevent excessive temperature elevation at the body surface. However, international standards and guidelines have different definitions for the size of the area over which the power density should be averaged. This study reports computational evaluation of the relationship between the size of the area over which incident power density is averaged and the local peak temperature elevation in a multi-layer model simulating a human body. Three wave sources are considered in the frequency range from 3 to 300 GHz: an ideal beam, a half-wave dipole antenna, and an antenna array. 1D analysis shows that averaging area of 20 mm  ×  20 mm is a good measure to correlate with the local peak temperature elevation when the field distribution is nearly uniform in that area. The averaging area is different from recommendations in the current international standards/guidelines, and not dependent on the frequency. For a non-uniform field distribution, such as a beam with small diameter, the incident power density should be compensated by multiplying a factor that can be derived from the ratio of the effective beam area to the averaging area. The findings in the present study suggest that the relationship obtained using the 1D approximation is applicable for deriving the relationship between the incident power density and the local temperature elevation.

Investigation of Main Radiation Source above Shield Plug of Unit 3 at Fukushima Daiichi Nuclear Power Station

NASA Astrophysics Data System (ADS)

Hiratama, Hideo; Kondo, Kenjiro; Suzuki, Seishiro; Tanimura, Yoshihiko; Iwanaga, Kohei; Nagata, Hiroshi

2017-09-01

Pulse height distributions were measured using a CdZnTe detector inside a lead collimator to investigate main source producing high dose rates above the shield plugs of Unit 3 at Fukushima Daiichi Nuclear Power Station. It was confirmed that low energy photons are dominant. Concentrations of Cs-137 under 60 cm concrete of the shield plug were estimated to be between 8.1E+9 and 5.7E+10 Bq/cm2 from the measured peak count rate of 0.662 MeV photons. If Cs-137 was distributed on the surfaces of the gaps with radius 6m and with the averaged concentration of 5 points, 2.6E+10 Bq/cm2, total amount of Cs-137 is estimated to be 30 PBq.

Oxygen production rates for P/Halley over much of the 1985-1986 apparition

NASA Technical Reports Server (NTRS)

Spinrad, Hyron; Mccarthy, Patrick J.; Strauss, Michael A.

1986-01-01

Long slit CCD spectrophotometry of comet P/Halley in the visible region was used to measure the production rate of atomic oxygen during the 1985/86 apparition. The observations cover a large range of heliocentric distances, since the technique is applicable to apparently bright and faint comets. The cometary gas production rate for P/Halley increases rapidly with decreasing heliocentric distance toward perihelion and is systematicaly larger at a given heliocentric distance for the postperihelion observations. The average production rate for O1D on the day of the Giotto flyby is 4 times 10 to the 28th power atoms/sec giving an extrapolated total water production rate of 6 times 10 to the 29th power mols/sec. A method for comparing the absolute cometary gas production rates for different comets is discussed.

FDTD computation of temperature elevation in the elderly for far-field RF exposures.

PubMed

Nomura, Tomoki; Laakso, Ilkka; Hirata, Akimasa

2014-03-01

Core temperature elevation and perspiration in younger and older adults is investigated for plane-wave exposure at whole-body averaged specific absorption rate of 0.4 W kg(-1). Numeric Japanese male model is considered together with a thermoregulatory response formula proposed in the authors' previous study. The frequencies considered were at 65 MHz and 2 GHz where the total power absorption in humans becomes maximal for the allowable power density prescribed in the international guidelines. From the computational results used here, the core temperature elevation in the older adult model was larger than that in the younger one at both frequencies. The reason for this difference is attributable to the difference of sweating, which is originated from the difference in the threshold activating the sweating and the decline in sweating in the legs.

Independent Analysis of Real-Time, Measured Performance Data From Microcogenerative Fuel Cell Systems Installed in Buildings

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

Dillon, Heather E.; Colella, Whitney G.

2015-06-01

Pacific Northwest National Laboratory (PNNL) is working with industry to independently monitor up to 15 distinct 5 kW-electric (kWe) combined heat and power (CHP) high temperature (HT) proton exchange membrane (PEM) fuel cell systems (FCSs) installed in light commercial buildings. This research paper discusses an evaluation of the first six months of measured performance data acquired at a 1 s sampling rate from real-time monitoring equipment attached to the FCSs at building sites. Engineering performance parameters are independently evaluated. Based on an analysis of the first few months of measured operating data, FCS performance is consistent with manufacturer-stated performance. Initialmore » data indicate that the FCSs have relatively stable performance and a long-term average production of about 4.57 kWe of power. This value is consistent with, but slightly below, the manufacturer's stated rated electric power output of 5 kWe. The measured system net electric efficiency has averaged 33.7%, based on the higher heating value (HHV) of natural gas fuel. This value, also, is consistent with, but slightly below, the manufacturer's stated rated electric efficiency of 36%. The FCSs provide low-grade hot water to the building at a measured average temperature of about 48.4 degrees C, lower than the manufacturer's stated maximum hot water delivery temperature of 65 degrees C. The uptime of the systems is also evaluated. System availability can be defined as the quotient of total operating time compared to time since commissioning. The average values for system availability vary between 96.1 and 97.3%, depending on the FCS evaluated in the field. Performance at rated value for electrical efficiency (PRVeff) can be defined as the quotient of the system time operating at or above the rated electric efficiency and the time since commissioning. The PRVeff varies between 5.6% and 31.6%, depending on the FCS field unit evaluated. Performance at rated value for electrical power (PRVp) can be defined as the quotient of the system time operating at or above the rated electric power and the time since commissioning. PRVp varies between 6.5% and 16.2%. Performance at rated value for electrical efficiency and power (PRVt) can be defined as the quotient of the system time operating at or above both the rated electric efficiency and the electric power output compared to the time since commissioning. PRVt varies between 0.2% and 1.4%. Optimization to determine the manufacturer rating required to achieve PRVt greater than 80% has been performed based on the collected data. For example, for FCS Unit 130 to achieve a PRVt of 95%, it would have to be down-rated to an electrical power output of 3.2 kWe and an electrical efficiency of 29%. The use of PRV as an assessment metric for FCSs has been developed and reported for the first time in this paper. For FCS Unit 130, a maximum decline in electric power output of approximately 18% was observed over a 500 h period in Jan. 2012.« less

Plasma core power exhaust in ELMy H-Mode in JET with ITER-Like Wall

NASA Astrophysics Data System (ADS)

Guillemaut, C.; Metzger, C.; Appel, L.; Drewelow, P.; Horvath, L.; Matthews, G. F.; Szepesi, G.; Solano, E. R.; contributors, JET

2018-07-01

The mitigation of target heat load in future steady state fusion devices will require dissipation of a significant amount of power through radiation. Plasma operations relying on ELMy H-modes could be problematic since ELMs may transport substantial amounts of power to the target without significant dissipation. Therefore, estimation of the average ELM power exhaust from the plasma core is crucial to evaluate the potential limitation on the power dissipation in ELMy H-mode regime. A series of more than 50 Type-I ELMy H-mode discharges in JET with ITER-Like Wall (JET-ILW) with a wide range of conditions has been used here to compare the average ELM power to the average input power. The effect of input power, ELM frequency, plasma current, confinement and radiation on ELM power exhaust has been studied and reported in this paper. Good agreement has been found here with previous studies made in carbon machines. This work suggests that it should not be possible to dissipate more than 70%–80% of the input power in Type-I ELMy H-modes in JET-ILW which is consistent with the maximum radiative fraction found experimentally.

Calculated power distribution of a thermionic, beryllium oxide reflected, fast-spectrum reactor

NASA Technical Reports Server (NTRS)

Mayo, W.; Lantz, E.

1973-01-01

A procedure is developed and used to calculate the detailed power distribution in the fuel elements next to a beryllium oxide reflector of a fast-spectrum, thermionic reactor. The results of the calculations show that, although the average power density in these outer fuel elements is not far from the core average, the power density at the very edge of the fuel closest to the beryllium oxide is about 1.8 times the core avearge.

Technical options for high average power free electron milimeter-wave and laser devices

NASA Technical Reports Server (NTRS)

Swingle, James C.

1989-01-01

Many of the potential space power beaming applications require the generation of directed energy beams with respectable amounts of average power (MWs). A tutorial summary is provided here on recent advances in the laboratory aimed at producing direct conversion of electrical energy to electromagnetic radiation over a wide spectral regime from microwaves to the ultraviolet.

Compact Tunable Narrowband Terahertz-Wave Source Based on Difference Frequency Generation Pumped by Dual Fiber Lasers in MgO:LiNbO3

NASA Astrophysics Data System (ADS)

Wada, Yoshio; Satoh, Takumi; Higashi, Yasuhiro; Urata, Yoshiharu

2017-12-01

We demonstrate a high-average-power, single longitudinal-mode, and tunable terahertz (THz)-wave source based on difference frequency generation (DFG) in a MgO:LiNbO3 (MgO:LN) crystal. The waves for DFG are generated using a pair of Yb-doped pulsed fiber lasers with a master oscillator power fiber amplifier configuration. The average power of the THz-wave output reaches 450 μW at 1.07 THz (280 μm) at a linewidth of 7.2 GHz, and the tunability ranges from 0.35 to 1.07 THz under the pulse repetition frequency of 500 kHz. A short burn-in test of the THz wave is also carried out, and the output power stability is within ± 5% of the averaged power without any active stabilizing technique. The combination of MgO:LN-DFG and stable and robust fiber laser sources is highly promising for the development of high-average-power THz-wave sources, particularly in the high transmission sub-THz region. This approach may enable new applications of THz-wave spectroscopy in imaging and remote sensing.

Analysis of the local worst-case SAR exposure caused by an MRI multi-transmit body coil in anatomical models of the human body.

PubMed

Neufeld, Esra; Gosselin, Marie-Christine; Murbach, Manuel; Christ, Andreas; Cabot, Eugenia; Kuster, Niels

2011-08-07

Multi-transmit coils are increasingly being employed in high-field magnetic resonance imaging, along with a growing interest in multi-transmit body coils. However, they can lead to an increase in whole-body and local specific absorption rate (SAR) compared to conventional body coils excited in circular polarization for the same total incident input power. In this study, the maximum increase of SAR for three significantly different human anatomies is investigated for a large 3 T (128 MHz) multi-transmit body coil using numerical simulations and a (generalized) eigenvalue-based approach. The results demonstrate that the increase of SAR strongly depends on the anatomy. For the three models and normalization to the sum of the rung currents squared, the whole-body averaged SAR increases by up to a factor of 1.6 compared to conventional excitation and the peak spatial SAR (averaged over any 10 cm(3) of tissue) by up to 13.4. For some locations the local averaged SAR goes up as much as 800 times (130 when looking only at regions where it is above 1% of the peak spatial SAR). The ratio of the peak spatial SAR to the whole-body SAR increases by a factor of up to 47 and can reach values above 800. Due to the potentially much larger power deposition, additional, preferably patient-specific, considerations are necessary to avoid injuries by such systems.

Does IQ explain socio-economic differentials in total and cardiovascular disease mortality? Comparison with the explanatory power of traditional cardiovascular disease risk factors in the Vietnam Experience Study.

PubMed

Batty, G David; Shipley, Martin J; Dundas, Ruth; Macintyre, Sally; Der, Geoff; Mortensen, Laust H; Deary, Ian J

2009-08-01

The aim of this study was to examine the explanatory power of intelligence (IQ) compared with traditional cardiovascular disease (CVD) risk factors in the relationship of socio-economic disadvantage with total and CVD mortality, that is the extent to which IQ may account for the variance in this well-documented association. Cohort study of 4289 US male former military personnel with data on four widely used markers of socio-economic position (early adulthood and current income, occupational prestige, and education), IQ test scores (early adulthood and middle-age), a range of nine established CVD risk factors (systolic and diastolic blood pressure, total blood cholesterol, HDL cholesterol, body mass index, smoking, blood glucose, resting heart rate, and forced expiratory volume in 1 s), and later mortality. We used the relative index of inequality (RII) to quantify the relation between each index of socio-economic position and mortality. Fifteen years of mortality surveillance gave rise to 237 deaths (62 from CVD and 175 from 'other' causes). In age-adjusted analyses, as expected, each of the four indices of socio-economic position was inversely associated with total, CVD, and 'other' causes of mortality, such that elevated rates were evident in the most socio-economically disadvantaged men. When IQ in middle-age was introduced to the age-adjusted model, there was marked attenuation in the RII across the socio-economic predictors for total mortality (average 50% attenuation in RII), CVD (55%), and 'other' causes of death (49%). When the nine traditional risk factors were added to the age-adjusted model, the comparable reduction in RII was less marked than that seen after IQ adjustment: all-causes (40%), CVD (40%), and 'other' mortality (43%). Adding IQ to the latter model resulted in marked, additional explanatory power for all outcomes in comparison to the age-adjusted analyses: all-causes (63%), CVD (63%), and 'other' mortality (65%). When we utilized IQ in early adulthood rather than middle-age as an explanatory variable, the attenuating effect on the socio-economic gradient was less pronounced although the same pattern was still present. In the present analyses of socio-economic gradients in total and CVD mortality, IQ appeared to offer greater explanatory power than that apparent for traditional CVD risk factors.

78 FR 19262 - Notice of Annual Adjustment of the Cap on Average Total Assets That Defines Community Financial...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-29

... FEDERAL HOUSING FINANCE AGENCY [No. 2013-N-04] Notice of Annual Adjustment of the Cap on Average.... ACTION: Notice. SUMMARY: The Federal Housing Finance Agency (FHFA) has adjusted the cap on average total... Federal Deposit Insurance Corporation and that has average total assets below a statutory cap.\\2\\ The Bank...

75 FR 9601 - Notice of Annual Adjustment of the Cap on Average Total Assets That Defines Community Financial...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-03

... FEDERAL HOUSING FINANCE AGENCY [No. 2010-N-01] Notice of Annual Adjustment of the Cap on Average.... ACTION: Notice. SUMMARY: The Federal Housing Finance Agency (FHFA) has adjusted the cap on average total... Deposit Insurance Corporation and that has average total assets below a statutory cap. See 12 U.S.C. 1422...

The predictive power of local properties of financial networks

NASA Astrophysics Data System (ADS)

Caraiani, Petre

2017-01-01

The literature on analyzing the dynamics of financial networks has focused so far on the predictive power of global measures of networks like entropy or index cohesive force. In this paper, I show that the local network properties have similar predictive power. I focus on key network measures like average path length, average degree or cluster coefficient, and also consider the diameter and the s-metric. Using Granger causality tests, I show that some of these measures have statistically significant prediction power with respect to the dynamics of aggregate stock market. Average path length is most robust relative to the frequency of data used or specification (index or growth rate). Most measures are found to have predictive power only for monthly frequency. Further evidences that support this view are provided through a simple regression model.

Pulsed power systems for environmental and industrial applications

NASA Astrophysics Data System (ADS)

Neau, E. L.

1994-10-01

The development of high peak power simulators, laser drivers, free electron lasers, and Inertial Confinement Fusion drivers is being extended to high average power short-pulse machines with the capabilities of performing new roles in environmental cleanup and industrial manufacturing processes. We discuss a new class of short-pulse, high average power accelerator that achieves megavolt electron and ion beams with 10's of kiloamperes of current and average power levels in excess of 100 kW. Large treatment areas are possible with these systems because kilojoules of energy are available in each output pulse. These systems can use large area x-ray converters for applications requiring grater depth of penetration such as food pasteurization and waste treatment. The combined development of this class of accelerators and applications, and Sandia National Laboratories, is called Quantum Manufacturing.

Characterization of advanced electric propulsion systems

NASA Technical Reports Server (NTRS)

Ray, P. K.

1982-01-01

Characteristics of several advanced electric propulsion systems are evaluated and compared. The propulsion systems studied are mass driver, rail gun, MPD thruster, hydrogen free radical thruster and mercury electron bombardment ion engine. These are characterized by specific impulse, overall efficiency, input power, average thrust, power to average thrust ratio and average thrust to dry weight ratio. Several important physical characteristics such as dry system mass, accelerator length, bore size and current pulse requirement are also evaluated in appropriate cases. Only the ion engine can operate at a specific impulse beyond 2000 sec. Rail gun, MPD thruster and free radical thruster are currently characterized by low efficiencies. Mass drivers have the best performance characteristics in terms of overall efficiency, power to average thrust ratio and average thrust to dry weight ratio. But, they can only operate at low specific impulses due to large power requirements and are extremely long due to limitations of driving current. Mercury ion engines have the next best performance characteristics while operating at higher specific impulses. It is concluded that, overall, ion engines have somewhat better characteristics as compared to the other electric propulsion systems.

The Physiological Profile of Junior Soccer Players at SSBB Surabaya Bhakti

NASA Astrophysics Data System (ADS)

Nashirudin, M.; Kusnanik, N. W.

2018-01-01

Soccer players are required to have good physical fitness in order to achieve optimum accomplishment; physical fitness stands as the foundation of technical and tactical proficiency as well as the mental maturity during the matches. The purpose of this study was to identify the physiological profile of junior soccer players of SSB Surabaya Bhakti age 16-17. The research was conducted at 20 junior soccer players. This research was quantitative with descriptive analysis. Data were collected by testing of physiological (anaerobic power and capacity including explosive leg power, speed, agility; aerobic capacity: cardiovascular endurance). Data was analyzed using percentage. The result showed that the percentage of explosive leg power of junior soccer players were 30% (good category), speed was 85% (average category), right agility was 90% (average category), left agility was 75% (average category). On the other hand, the aerobic power and capacity of the junior soccer players in this study was 50% (average category). The conclusion of this research is that the physiological profile of junior soccer players at SSB Surabaya Bhakti age 16-17 was majority in average category.

Fundamental formulae for wave-energy conversion.

PubMed

Falnes, Johannes; Kurniawan, Adi

2015-03-01

The time-average wave power that is absorbed from an incident wave by means of a wave-energy conversion (WEC) unit, or by an array of WEC units-i.e. oscillating immersed bodies and/or oscillating water columns (OWCs)-may be mathematically expressed in terms of the WEC units' complex oscillation amplitudes, or in terms of the generated outgoing (diffracted plus radiated) waves, or alternatively, in terms of the radiated waves alone. Following recent controversy, the corresponding three optional expressions are derived, compared and discussed in this paper. They all provide the correct time-average absorbed power. However, only the first-mentioned expression is applicable to quantify the instantaneous absorbed wave power and the associated reactive power. In this connection, new formulae are derived that relate the 'added-mass' matrix, as well as a couple of additional reactive radiation-parameter matrices, to the difference between kinetic energy and potential energy in the water surrounding the immersed oscillating WEC array. Further, a complex collective oscillation amplitude is introduced, which makes it possible to derive, by a very simple algebraic method, various simple expressions for the maximum time-average wave power that may be absorbed by the WEC array. The real-valued time-average absorbed power is illustrated as an axisymmetric paraboloid defined on the complex collective-amplitude plane. This is a simple illustration of the so-called 'fundamental theorem for wave power'. Finally, the paper also presents a new derivation that extends a recently published result on the direction-average maximum absorbed wave power to cases where the WEC array's radiation damping matrix may be singular and where the WEC array may contain OWCs in addition to oscillating bodies.

What is the Impact of Utility Demand Charges on a DCFC host

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

Francfort, James Edward

The PEV Electric Vehicle Supply Equipment (EVSE) delivered by The EV Project included both AC Level 2 and DCFC units. Over 100 of these dual-port Blink DC fast chargers were deployed by The EV Project. These DCFCs were installed in workplaces and in publicly accessible locations near traffic hubs, retail centers, parking lots, restaurants, and similar locations. The Blink DCFC is capable of charging at power up to 60 kW. Its dual-port design sequences the charge from one port to the other, delivering power to only one of two vehicles connected at a time. The actual power delivered through amore » port is determined by the PEV’s on-board battery management system (BMS). Both the power and the total energy used to recharge a PEV can represent a significant cost for the charging site host. Many electric utilities impose fees for power demand as part of their commercial rate structure. The demand charge incurred by a customer is related to the peak power used during a monthly billing cycle. This is in contrast to the cumulative total energy usage that is the more familiar utility charge seen for most residential services. A demand charge is typically assessed for the highest average power over any 15 minute interval during the monthly billing cycle. One objective of The EV Project was to identify and elucidate the motivations and barriers to potential DCFC site hosts. The application of electric utility demand charges is one such potential barrier. This subject was introduced in the paper: DC Fast Charge - Demand Charge Reduction1. It discussed demand charge impact in general terms in order to focus on potential mitigation actions. This paper identifies specific cases in order to quantify the impact of demand charges on EV Project DCFC hosts.« less

Superlinear scaling of offspring at criticality in branching processes

NASA Astrophysics Data System (ADS)

Saichev, A.; Sornette, D.

2014-01-01

For any branching process, we demonstrate that the typical total number rmp(ντ) of events triggered over all generations within any sufficiently large time window τ exhibits, at criticality, a superlinear dependence rmp(ντ)˜(ντ)γ (with γ >1) on the total number ντ of the immigrants arriving at the Poisson rate ν. In branching processes in which immigrants (or sources) are characterized by fertilities distributed according to an asymptotic power-law tail with tail exponent 1<γ ⩽2, the exponent of the superlinear law for rmp(ντ) is identical to the exponent γ of the distribution of fertilities. For γ >2 and for standard branching processes without power-law distribution of fertilities, rmp(ντ)˜(ντ)2. This scaling law replaces and tames the divergence ντ /(1-n) of the mean total number R¯t(τ) of events, as the branching ratio (defined as the average number of triggered events of first generation per source) tends to 1. The derivation uses the formalism of generating probability functions. The corresponding prediction is confirmed by numerical calculations, and an heuristic derivation enlightens its underlying mechanism. We also show that R¯t(τ) is always linear in ντ even at criticality (n =1). Our results thus illustrate the fundamental difference between the mean total number, which is controlled by a few extremely rare realizations, and the typical behavior represented by rmp(ντ).

Sedimentation and mobility of PDCs: a reappraisal of ignimbrites' aspect ratio.

PubMed

Giordano, Guido; Doronzo, Domenico M

2017-06-30

The aspect ratio of ignimbrites is a commonly used parameter that has been related to the energy of the parent pyroclastic density currents (PDCs). However this parameter, calculated as the ratio between the average thickness and the average lateral extent of ignimbrites, does not capture fundamental differences in pyroclastic flow mobility nor relates to lithofacies variations of the final deposits. We herein introduce the "topological aspect ratio" (ARt) as the ratio of the local deposit thickness (Ht) to the distance between the local site and the maximum runout distance (Lt), where Ht is a proxy for the PDC tendency to deposit, and Lt a proxy for the PDC mobility or its tendency to further transport the pyroclastic material. The positive versus negative spatial gradient d(ARt)/dx along flow paths discriminate zones where PDCs are forced (i.e. where they transport the total energy under the action of mass discharge rate) from zones where they are inertial (i.e. where they transport the total energy under the action of viscous or turbulent fluidization). Though simple to apply, the topological aspect ratio and its spatial gradient are powerful descriptors of the interplay between sedimentation and mobility of PDCs, and of the resulting lithofacies variations.

Normalized knee-extension strength or leg-press power after fast-track total knee arthroplasty: which measure is most closely associated with performance-based and self-reported function?

PubMed

Aalund, Peter K; Larsen, Kristian; Hansen, Torben B; Bandholm, Thomas

2013-02-01

To investigate which of the 2 muscle-impairment measures for the operated leg, normalized knee extension strength or leg press power, was most closely associated with performance-based and self-reported measures of function shortly after total knee arthroplasty (TKA). Cross-sectional, exploratory study. Laboratory at a regional hospital. Individuals (N=39) with an average age ± SD of 65.5±10.3 years, who all had unilateral TKA 28 days prior. None. The patients performed maximal isometric knee extensions and dynamic leg presses to determine their body-mass normalized knee extension strength and leg press power, respectively. The 10-meter fast speed walking- and 30-second chair stand tests were used to determine performance-based function, while the Western Ontario and McMaster Universities Osteoarthritis Index and Oxford Knee Scores were used to determine self-reported function. Normalized leg press power was more closely associated with both performance-based (r=.82, P<.001) and self-reported (r=.48, P=.002) measures of function compared with normalized knee extension strength (r=.51, P=.001 and r=.39, P=.015, respectively). Normalized leg press power was more closely associated with both performance-based and self-reported function early after TKA than normalized knee extension strength. It may be explained by the fact that performance-based measures of function are typically closed kinetic chain tasks, such as walking or rising from a chair, and self-reported measures of function typically include questions that address perceived difficulty with performing these same tasks. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

The 2nd order focusing sector field type TOF mass analyzer with an orthogonal ion acceleration for LC-IMS-MS.

PubMed

Poteshin, S S; Zarakovsky, A I

2017-03-15

Original orthogonal acceleration (OA) electrostatic sector time of flight (TOF) mass analyzer is proposed those allows the second order focusing of time of flight by initial ions position. Resolving power aberration limit exceeding 80,000 FW (full width mass peak) was shown to be obtainable for mass analyzer with the total length of flight L=133.2cm, the average ion energy 3700V and the ion energy spread of 2.5% on the entrance of sector field. Copyright © 2016 Elsevier B.V. All rights reserved.

Solar wind thermal electrons in the ecliptic plane between 1 and 4 AU - Preliminary results from the Ulysses radio receiver

NASA Technical Reports Server (NTRS)

Hoang, S.; Meyer-Vernet, N.; Bougeret, J.-L.; Harvey, C. C.; Lacombe, C.; Mangeney, A.; Moncuquet, M.; Perche, C.; Steinberg, J.-L.; Macdowall, R. J.

1992-01-01

The radio receiver of the Unified Radio and Plasma experiment aboard the Ulysses spacecraft records spectra of the quasi-thermal plasma noise. The interpretation of these spectra allows the determination of the total electron density Ne and of the cold (core) electron temperature Tc in the solar wind. A single power law does not fit the variations of Ne which result from the contribution from different solar wind structures. The distribution of the values of Tc suggests that, on the average, the solar wind is nearly isothermal.

Efficient blue conversion from a 1064 nm microchip laser in long photonic crystal fiber tapers for fluorescence microscopy.

PubMed

Kudlinski, A; Lelek, M; Barviau, B; Audry, L; Mussot, A

2010-08-02

Using a low-cost microchip laser and a long photonic crystal fiber taper, we report a supercontinuum source with a very efficient visible conversion, especially in the blue region (around 420 nm). About 30 % of the total average output power is located in the 350-600 nm band, which is of primary importance in a number of biophotonics applications such as flow cytometry or fluorescence imaging microscopy for instance. We successfully demonstrate the use of this visible-enhanced source for a three-color imaging of HeLa cells in wide-field microscopy.

Investigation on high transmission efficiency 7 × 1 pump combiner

NASA Astrophysics Data System (ADS)

Cao, Yang; Shi, Wei; Sheng, Quan; Fu, Shijie; Zhang, Haiwei; Bai, Xiaolei; Qi, Liang; Yao, Jianquan

2016-12-01

The 7×1 end-pumped combiner employing 105/125 μm multimode fibers as pump fibers is investigated. The theoretical analysis reveals that sufficient taper length and low refractive index of the capillary should be adopted to fabricate high transmission efficiency combiners. Based on the simulation results, we fabricate a 7×1 end-pumped pump combiner with an average transmission efficiency of 98.9% and a total return loss of 1.1‰. The measured internal operating temperature of this combiner indicates it can endure pump power of the order of kilowatts.

In vivo assessment of diet-induced rat hepatic steatosis development by percutaneous single-fiber spectroscopy detects scattering spectral changes due to fatty infiltration

NASA Astrophysics Data System (ADS)

Piao, Daqing; Sultana, Nigar; Holyoak, G. Reed; Ritchey, Jerry W.; Wall, Corey R.; Murray, Jill K.; Bartels, Kenneth E.

2015-11-01

This study explores percutaneous single-fiber spectroscopy (SfS) of rat livers undergoing fatty infiltration. Eight test rats were fed a methionine-choline-deficient (MCD) diet, and four control rats were fed a normal diet. Two test rats and one control rat were euthanized on days 12, 28, 49, and 77 following initiation of the diet, after percutaneous SfS of the liver under transabdominal ultrasound guidance. Histology of each set of the two euthanized test rats showed mild and mild hepatic lipid accumulations on day 12, moderate and severe on day 28, severe and mild on day 49, and moderate and mild on day 77. Livers with moderate or higher lipid accumulation generally presented higher spectral reflectance intensity when compared to lean livers. Livers of the eight test rats on day 12, two of which had mild lipid accumulation, revealed an average scattering power of 0.37±0.14 in comparison to 0.07±0.14 for the four control rats (p<0.01). When livers of the test rats with various levels of fatty infiltration were combined, the average scattering power was 0.36±0.15 in comparison to 0.14±0.24 of the control rats (0.05

Suppression of AC railway power-line interference in ECG signals recorded by public access defibrillators

PubMed Central

Dotsinsky, Ivan

2005-01-01

Background Public access defibrillators (PADs) are now available for more efficient and rapid treatment of out-of-hospital sudden cardiac arrest. PADs are used normally by untrained people on the streets and in sports centers, airports, and other public areas. Therefore, automated detection of ventricular fibrillation, or its exclusion, is of high importance. A special case exists at railway stations, where electric power-line frequency interference is significant. Many countries, especially in Europe, use 16.7 Hz AC power, which introduces high level frequency-varying interference that may compromise fibrillation detection. Method Moving signal averaging is often used for 50/60 Hz interference suppression if its effect on the ECG spectrum has little importance (no morphological analysis is performed). This approach may be also applied to the railway situation, if the interference frequency is continuously detected so as to synchronize the analog-to-digital conversion (ADC) for introducing variable inter-sample intervals. A better solution consists of rated ADC, software frequency measuring, internal irregular re-sampling according to the interference frequency, and a moving average over a constant sample number, followed by regular back re-sampling. Results The proposed method leads to a total railway interference cancellation, together with suppression of inherent noise, while the peak amplitudes of some sharp complexes are reduced. This reduction has negligible effect on accurate fibrillation detection. Conclusion The method is developed in the MATLAB environment and represents a useful tool for real time railway interference suppression. PMID:16309558

Development of optically pumped DBR-free semiconductor disk lasers (Conference Presentation)

NASA Astrophysics Data System (ADS)

Yang, Zhou; Albrecht, Alexander R.; Cederberg, Jeffrey G.; Sheik-Bahae, Mansoor

2017-03-01

Semiconductor disk lasers (SDLs) are attractive for applications requiring good beam quality, wavelength versatility, and high output powers. Typical SDLs utilize the active mirror geometry, where a semiconductor DBR is integrated with the active region by growth or post-growth bonding. This imposes restrictions for the SDL design, like material system choice, thermal management, and effective gain bandwidth. In DBR-free geometry, these restrictions can be alleviated. An integrated gain model predicts DBR-free geometry with twice the gain bandwidth of typical SDLs, which has been experimentally verified with active regions near 1 μm and 1.15 μm. The lift-off and bonding technique enables the integration of semiconductor active regions with arbitrary high quality substrates, allowing novel monolithic geometries. Bonding an active region onto a straight side of a commercial fused silica right angle prism, and attaching a high reflectivity mirror onto the hypotenuse side, with quasi CW pumping at 780 nm, lasing operation was achieved at 1037 nm with 0.2 mW average power at 1.6 mW average pump power. Laser dynamics show that thermal lens generation in the active region bottlenecks the laser efficiency. Investigations on total internal reflection based monolithic ring cavities are ongoing. These geometries would allow the intracavity integration of 2D materials or other passive absorbers, which could be relevant for stable mode locking. Unlike typical monolithic microchip SDLs, with the evanescent wave coupling technique, these monolithic geometries allow variable coupling efficiency.

Suppression of AC railway power-line interference in ECG signals recorded by public access defibrillators.

PubMed

Dotsinsky, Ivan

2005-11-26

Public access defibrillators (PADs) are now available for more efficient and rapid treatment of out-of-hospital sudden cardiac arrest. PADs are used normally by untrained people on the streets and in sports centers, airports, and other public areas. Therefore, automated detection of ventricular fibrillation, or its exclusion, is of high importance. A special case exists at railway stations, where electric power-line frequency interference is significant. Many countries, especially in Europe, use 16.7 Hz AC power, which introduces high level frequency-varying interference that may compromise fibrillation detection. Moving signal averaging is often used for 50/60 Hz interference suppression if its effect on the ECG spectrum has little importance (no morphological analysis is performed). This approach may be also applied to the railway situation, if the interference frequency is continuously detected so as to synchronize the analog-to-digital conversion (ADC) for introducing variable inter-sample intervals. A better solution consists of rated ADC, software frequency measuring, internal irregular re-sampling according to the interference frequency, and a moving average over a constant sample number, followed by regular back re-sampling. The proposed method leads to a total railway interference cancellation, together with suppression of inherent noise, while the peak amplitudes of some sharp complexes are reduced. This reduction has negligible effect on accurate fibrillation detection. The method is developed in the MATLAB environment and represents a useful tool for real time railway interference suppression.

Operational frequency stability of rubidium and cesium frequency standards

NASA Technical Reports Server (NTRS)

Lavery, J. E.

1973-01-01

The frequency stabilities under operational conditions of several commercially available rubidium and cesium frequency standards were determined from experimental data for frequency averaging times from 10 to the 7th power s and are presented in table and graph form. For frequency averaging times between 10 to the 5th power and 10 to the 7th power s, the rubidium standards tested have a stability of between 10 to the minus 12th power and 5 x 10 to the minus 12th power, while the cesium standards have a stability of between 2 x 10 to the minus 13th power and 5 x 10 to the minus 13th power.

76 FR 3142 - Notice of Annual Adjustment of the Cap on Average Total Assets That Defines Community Financial...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-19

... FEDERAL HOUSING FINANCE AGENCY [No. 2011-N-01] Notice of Annual Adjustment of the Cap on Average.... ACTION: Notice. SUMMARY: The Federal Housing Finance Agency (FHFA) has adjusted the cap on average total... average total assets below a statutory cap. See 12 U.S.C. 1422(10)(A); 12 CFR 1263.1. The Bank Act was...

Administration costs of intravenous biologic drugs for rheumatoid arthritis.

PubMed

Soini, Erkki J; Leussu, Miina; Hallinen, Taru

2013-01-01

Cost-effectiveness studies explicitly reporting infusion times, drug-specific administration costs for infusions or real-payer intravenous drug cost are few in number. Yet, administration costs for infusions are needed in the health economic evaluations assessing intravenously-administered drugs. To estimate the drug-specific administration and total cost of biologic intravenous rheumatoid arthritis (RA) drugs in the adult population and to compare the obtained costs with published cost estimates. Cost price data for the infusions and drugs were systematically collected from the 2011 Finnish price lists. All Finnish hospitals with available price lists were included. Drug administration and total costs (administration cost + drug price) per infusion were analysed separately from the public health care payer's perspective. Further adjustments for drug brand, dose, and hospital type were done using regression methods in order to improve the comparability between drugs. Annual expected drug administration and total costs were estimated. A literature search not limited to RA was performed to obtain the per infusion administration cost estimates used in publications. The published costs were converted to Finnish values using base-year purchasing power parities and indexing to the year 2011. Information from 19 (95%) health districts was obtained (107 analysable prices out of 176 observations). The average drug administration cost for infliximab, rituximab, abatacept, and tocilizumab infusion in RA were €355.91; €561.21; €334.00; and €293.96, respectively. The regression-adjusted (dose, hospital type; using semi-log ordinary least squares) mean administration costs for infliximab and rituximab infusions in RA were €289.12 (95% CI €222.61-375.48) and €542.28 (95% CI €307.23-957.09). The respective expected annual drug administration costs were €2312.96 for infliximab during the first year, €1879.28 for infliximab during the forthcoming years, and €1843.75 for rituximab. The obtained average administration costs per infusion were higher (1.8-3.3 times depending on the drug) than the previously published purchasing power adjusted and indexed average administration costs for infusions in RA. The administration costs of RA infusions vary between drugs, and more effort should be made to find realistic drug-specific estimates for cost-effectiveness evaluations. The frequent assumption of intravenous drug administration costs equalling outpatient visit cost can underestimate the costs.

The Relationship Between X-Ray Radiance and Magnetic Flux

NASA Astrophysics Data System (ADS)

Pevtsov, Alexei A.; Fisher, George H.; Acton, Loren W.; Longcope, Dana W.; Johns-Krull, Christopher M.; Kankelborg, Charles C.; Metcalf, Thomas R.

2003-12-01

We use soft X-ray and magnetic field observations of the Sun (quiet Sun, X-ray bright points, active regions, and integrated solar disk) and active stars (dwarf and pre-main-sequence) to study the relationship between total unsigned magnetic flux, Φ, and X-ray spectral radiance, LX. We find that Φ and LX exhibit a very nearly linear relationship over 12 orders of magnitude, albeit with significant levels of scatter. This suggests a universal relationship between magnetic flux and the power dissipated through coronal heating. If the relationship can be assumed linear, it is consistent with an average volumetric heating rate Q~B/L, where B is the average field strength along a closed field line and L is its length between footpoints. The Φ-LX relationship also indicates that X-rays provide a useful proxy for the magnetic flux on stars when magnetic measurements are unavailable.

Dissolved Copper, Nickel and Lead in Tampamachoco Lagoon and Tuxpan River Estuary in the SW Gulf of Mexico.

PubMed

Garduño Ruiz, E P; Rosales Hoz, L; Carranza Edwards, A

2016-10-01

In order to estimate the effects of a thermal power plant, physicochemical parameters and the concentrations of copper, nickel and lead were evaluated in water from both Tampamachoco Lagoon and the estuary of the Tuxpan River. Average salinities were 33.66 ups in the lagoon area, 32.77 ups in the channel that joins the lagoon and the river, and 24.74 ups in the river estuary. Total average metal concentrations were 21.95 for Cu, 29.67 for Ni and 4.31 µ/L for Pb. Sampling point 1 and samples from the bottom water of the lagoon present the highest salinities and concentrations of suspended matter, TOC, Cu, Ni and Pb.These high values may be associated with the infiltration of sea water either from plant operation or from the channel that connects the lagoon with the sea.

Exposure to atmospheric radon.

PubMed Central

Steck, D J; Field, R W; Lynch, C F

1999-01-01

We measured radon (222Rn) concentrations in Iowa and Minnesota and found that unusually high annual average radon concentrations occur outdoors in portions of central North America. In some areas, outdoor concentrations exceed the national average indoor radon concentration. The general spatial patterns of outdoor radon and indoor radon are similar to the spatial distribution of radon progeny in the soil. Outdoor radon exposure in this region can be a substantial fraction of an individual's total radon exposure and is highly variable across the population. Estimated lifetime effective dose equivalents for the women participants in a radon-related lung cancer study varied by a factor of two at the median dose, 8 mSv, and ranged up to 60 mSv (6 rem). Failure to include these doses can reduce the statistical power of epidemiologic studies that examine the lung cancer risk associated with residential radon exposure. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:9924007

Combined Effects of Lignosus rhinocerotis Supplementation and Resistance Training on Isokinetic Muscular Strength and Power, Anaerobic and Aerobic Fitness Level, and Immune Parameters in Young Males.

PubMed

Chen, Chee Keong; Hamdan, Nor Faeiza; Ooi, Foong Kiew; Wan Abd Hamid, Wan Zuraida

2016-01-01

This study investigated the effects of Lignosus rhinocerotis (LRS) supplementation and resistance training (RT) on isokinetic muscular strength and power, anaerobic and aerobic fitness, and immune parameters in young males. Participants were randomly assigned to four groups: Control (C), LRS, RT, and combined RT-LRS (RT-LRS). Participants in the LRS and RT-LRS groups consumed 500 mg of LRS daily for 8 weeks. RT was conducted 3 times/week for 8 weeks for participants in the RT and RT-LRS groups. The following parameters were measured before and after the intervention period: Anthropometric data, isokinetic muscular strength and power, and anaerobic and aerobic fitness. Blood samples were also collected to determine immune parameters. Isokinetic muscular strength and power were increased ( P < 0.05) in participants of both RT and RT-LRS groups. RT-LRS group had shown increases ( P < 0.05) in shoulder extension peak torque, shoulder flexion and extension average power, knee flexion peak torque, and knee flexion and extension average power. There were also increases ( P < 0.05) in anaerobic power and capacity and aerobic fitness in this group. Similarly, RT group had increases ( P < 0.05) in shoulder flexion average power, knee flexion and extension peak torque, and knee flexion and extension average power. In addition, increases ( P < 0.05) in anaerobic power and capacity, aerobic fitness, T lymphocytes (CD3 and CD4), and B lymphocytes (CD19) counts were observed in the RT group. RT elicited increased isokinetic muscular strength and power, anaerobic and aerobic fitness, and immune parameters among young males. However, supplementation with LRS during RT did not provide additive benefits.

Combined Effects of Lignosus rhinocerotis Supplementation and Resistance Training on Isokinetic Muscular Strength and Power, Anaerobic and Aerobic Fitness Level, and Immune Parameters in Young Males

PubMed Central

Chen, Chee Keong; Hamdan, Nor Faeiza; Ooi, Foong Kiew; Wan Abd Hamid, Wan Zuraida

2016-01-01

Background: This study investigated the effects of Lignosus rhinocerotis (LRS) supplementation and resistance training (RT) on isokinetic muscular strength and power, anaerobic and aerobic fitness, and immune parameters in young males. Methods: Participants were randomly assigned to four groups: Control (C), LRS, RT, and combined RT-LRS (RT-LRS). Participants in the LRS and RT-LRS groups consumed 500 mg of LRS daily for 8 weeks. RT was conducted 3 times/week for 8 weeks for participants in the RT and RT-LRS groups. The following parameters were measured before and after the intervention period: Anthropometric data, isokinetic muscular strength and power, and anaerobic and aerobic fitness. Blood samples were also collected to determine immune parameters. Results: Isokinetic muscular strength and power were increased (P < 0.05) in participants of both RT and RT-LRS groups. RT-LRS group had shown increases (P < 0.05) in shoulder extension peak torque, shoulder flexion and extension average power, knee flexion peak torque, and knee flexion and extension average power. There were also increases (P < 0.05) in anaerobic power and capacity and aerobic fitness in this group. Similarly, RT group had increases (P < 0.05) in shoulder flexion average power, knee flexion and extension peak torque, and knee flexion and extension average power. In addition, increases (P < 0.05) in anaerobic power and capacity, aerobic fitness, T lymphocytes (CD3 and CD4), and B lymphocytes (CD19) counts were observed in the RT group. Conclusions: RT elicited increased isokinetic muscular strength and power, anaerobic and aerobic fitness, and immune parameters among young males. However, supplementation with LRS during RT did not provide additive benefits. PMID:27833721

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

Isotalo, Aarno

A method referred to as tally nuclides is presented for accurately and efficiently calculating the time-step averages and integrals of any quantities that are weighted sums of atomic densities with constant weights during the step. The method allows all such quantities to be calculated simultaneously as a part of a single depletion solution with existing depletion algorithms. Some examples of the results that can be extracted include step-average atomic densities and macroscopic reaction rates, the total number of fissions during the step, and the amount of energy released during the step. Furthermore, the method should be applicable with several depletionmore » algorithms, and the integrals or averages should be calculated with an accuracy comparable to that reached by the selected algorithm for end-of-step atomic densities. The accuracy of the method is demonstrated in depletion calculations using the Chebyshev rational approximation method. Here, we demonstrate how the ability to calculate energy release in depletion calculations can be used to determine the accuracy of the normalization in a constant-power burnup calculation during the calculation without a need for a reference solution.« less

Calculating Time-Integral Quantities in Depletion Calculations

DOE PAGES

Isotalo, Aarno

2016-06-02

A method referred to as tally nuclides is presented for accurately and efficiently calculating the time-step averages and integrals of any quantities that are weighted sums of atomic densities with constant weights during the step. The method allows all such quantities to be calculated simultaneously as a part of a single depletion solution with existing depletion algorithms. Some examples of the results that can be extracted include step-average atomic densities and macroscopic reaction rates, the total number of fissions during the step, and the amount of energy released during the step. Furthermore, the method should be applicable with several depletionmore » algorithms, and the integrals or averages should be calculated with an accuracy comparable to that reached by the selected algorithm for end-of-step atomic densities. The accuracy of the method is demonstrated in depletion calculations using the Chebyshev rational approximation method. Here, we demonstrate how the ability to calculate energy release in depletion calculations can be used to determine the accuracy of the normalization in a constant-power burnup calculation during the calculation without a need for a reference solution.« less

The rate of transient beta frequency events predicts behavior across tasks and species

PubMed Central

Law, Robert; Tsutsui, Shawn; Moore, Christopher I; Jones, Stephanie R

2017-01-01

Beta oscillations (15-29Hz) are among the most prominent signatures of brain activity. Beta power is predictive of healthy and abnormal behaviors, including perception, attention and motor action. In non-averaged signals, beta can emerge as transient high-power 'events'. As such, functionally relevant differences in averaged power across time and trials can reflect changes in event number, power, duration, and/or frequency span. We show that functionally relevant differences in averaged beta power in primary somatosensory neocortex reflect a difference in the number of high-power beta events per trial, i.e. event rate. Further, beta events occurring close to the stimulus were more likely to impair perception. These results are consistent across detection and attention tasks in human magnetoencephalography, and in local field potentials from mice performing a detection task. These results imply that an increased propensity of beta events predicts the failure to effectively transmit information through specific neocortical representations. PMID:29106374

Adaptive pitch control for variable speed wind turbines

DOEpatents

Johnson, Kathryn E [Boulder, CO; Fingersh, Lee Jay [Westminster, CO

2012-05-08

An adaptive method for adjusting blade pitch angle, and controllers implementing such a method, for achieving higher power coefficients. Average power coefficients are determined for first and second periods of operation for the wind turbine. When the average power coefficient for the second time period is larger than for the first, a pitch increment, which may be generated based on the power coefficients, is added (or the sign is retained) to the nominal pitch angle value for the wind turbine. When the average power coefficient for the second time period is less than for the first, the pitch increment is subtracted (or the sign is changed). A control signal is generated based on the adapted pitch angle value and sent to blade pitch actuators that act to change the pitch angle of the wind turbine to the new or modified pitch angle setting, and this process is iteratively performed.

Power scaling of supercontinuum seeded megahertz-repetition rate optical parametric chirped pulse amplifiers.

PubMed

Riedel, R; Stephanides, A; Prandolini, M J; Gronloh, B; Jungbluth, B; Mans, T; Tavella, F

2014-03-15

Optical parametric chirped-pulse amplifiers with high average power are possible with novel high-power Yb:YAG amplifiers with kW-level output powers. We demonstrate a compact wavelength-tunable sub-30-fs amplifier with 11.4 W average power with 20.7% pump-to-signal conversion efficiency. For parametric amplification, a beta-barium borate crystal is pumped by a 140 W, 1 ps Yb:YAG InnoSlab amplifier at 3.25 MHz repetition rate. The broadband seed is generated via supercontinuum generation in a YAG crystal.

Nonlinear pulse compression stage delivering 43-W few-cycle pulses with GW peak-power at 2-μm wavelength

NASA Astrophysics Data System (ADS)

Gebhardt, Martin; Gaida, Christian; Heuermann, T.; Stutzki, F.; Jauregui, C.; Antonio-Lopez, J.; Schüuzgen, A.; Amezcua-Correa, R.; Tünnermann, A.; Limpert, J.

2018-02-01

In this contribution we demonstrate the nonlinear pulse compression of an ultrafast thulium-doped fiber laser down to 14 fs FWHM duration (sub-3 optical cycles) at a record average power of 43 W and 34.5 μJ pulse energy. To the best of our knowledge, we present the highest average power few-cycle laser source at 2 μm wavelength. This performance level in combination with GW-class peak power makes our laser source extremely interesting for driving high-harmonic generation or for generating mid-infrared frequency combs via intra-pulse frequency down-conversion at an unprecedented average power. The experiments were enabled by an ultrafast thulium-doped fiber laser delivering 110 fs pulses at high repetition rates, and an argon gas-filled antiresonant hollow-core fiber (ARHCF) with excellent transmission and weak anomalous dispersion, leading to the self-compression of the pulses. We have shown that ARHCFs are well-suited for nonlinear pulse compression around 2 μm wavelength and that this concept features excellent power handling capabilities. Based on this result, we discuss the next steps for energy and average power scaling including upscaling the fiber dimensions in order to fully exploit the capabilities of our laser system, which can deliver several GW of peak power. This way, a 100 W-class laser source with mJ-level few-cycle pulses at 2 μm wavelength is feasible in the near future.

[Fishery and biometrics of genus Calappa crabs (Brachyura: Calappidae) in northeastern Venezuela].

PubMed

Alió, José J; Marcano, Luis A; Altuve, Douglas E

2005-01-01

The box crabs, genus Calappa, are important crab species landed by the industrial trawl fleet in Venezuela. These crabs have a wide distribution in the country, from the Gulf of Venezuela to the Orinoco River, but major landings take place in such gulf, near Margarita Island and northern Sucre State. Average annual landing in the eastern region was 69 t during 1970-2001, with a maximum of 221 t. For this study a sample of 2 398 box crabs was collected by observers on board of industrial trawl vessels, which operated in eastern Venezuela from 1994 to 2000. Three species were found in the landings, Calappa sulcata and C. flammea. each represented 47% of the sample, and C. nitida, which accounted for 5% of the sample. Sex ratio was strongly biased towards males in C. sulcata (2.8:1) and in C. flammnea (1.9:1). while it was only slightly biased in C. nitida (1.4:1). Due to its large size, C. sulcuta is of great commercial interest, with average weight 290 g and a maximum weight of 720 g: C. flammea showed an average weight of 140 g and a maximum weight of 418 g, while C. nitida is the smallest species, with average weight 46 g and maximum weight not beyond 113 g. Box crabs were captured by day and night in similar proportions, and were found in a wide depth range, from a few meters to 126 m deep; however, the largest captures were obtained in the interval 38 - 54 m. Regressions between weight of chelae and total weight were linear, and significantly different between sexes. The relation between total weight and carapace width was allometric, with a power exponent ca. three in C. sulcata, and less than three in C. flamea and C. nitida. Females of C. sulcata and C. nitida showed power exponents significantly smaller than males. Since claws are removed from the animal to be commercialized, while the rest of the animal is returned alive to the sea, for practical purposes a common equation among species and sexes to convert claws weight into total body weight is: total weight - 3 x claws weight. The relationship between catch per unit of effort (CPUE) and effort did not show a significantly decreasing trend, but landings follow the effort trend, with a decreasing tendency in recent years. No mature females were found in any of the three species, thus there could be reproductive migrations towards deeper waters from October to January, when abundance of crabs is lower in the study area. It is recommended that the practice of exploiting only one claw, returning the rest of the animal alive to the sea, should be promoted among fishers, while the removal of claws from female crabs should be avoided.

Low statistical power in biomedical science: a review of three human research domains.

PubMed

Dumas-Mallet, Estelle; Button, Katherine S; Boraud, Thomas; Gonon, Francois; Munafò, Marcus R

2017-02-01

Studies with low statistical power increase the likelihood that a statistically significant finding represents a false positive result. We conducted a review of meta-analyses of studies investigating the association of biological, environmental or cognitive parameters with neurological, psychiatric and somatic diseases, excluding treatment studies, in order to estimate the average statistical power across these domains. Taking the effect size indicated by a meta-analysis as the best estimate of the likely true effect size, and assuming a threshold for declaring statistical significance of 5%, we found that approximately 50% of studies have statistical power in the 0-10% or 11-20% range, well below the minimum of 80% that is often considered conventional. Studies with low statistical power appear to be common in the biomedical sciences, at least in the specific subject areas captured by our search strategy. However, we also observe evidence that this depends in part on research methodology, with candidate gene studies showing very low average power and studies using cognitive/behavioural measures showing high average power. This warrants further investigation.

Low statistical power in biomedical science: a review of three human research domains

PubMed Central

Dumas-Mallet, Estelle; Button, Katherine S.; Boraud, Thomas; Gonon, Francois

2017-01-01

Studies with low statistical power increase the likelihood that a statistically significant finding represents a false positive result. We conducted a review of meta-analyses of studies investigating the association of biological, environmental or cognitive parameters with neurological, psychiatric and somatic diseases, excluding treatment studies, in order to estimate the average statistical power across these domains. Taking the effect size indicated by a meta-analysis as the best estimate of the likely true effect size, and assuming a threshold for declaring statistical significance of 5%, we found that approximately 50% of studies have statistical power in the 0–10% or 11–20% range, well below the minimum of 80% that is often considered conventional. Studies with low statistical power appear to be common in the biomedical sciences, at least in the specific subject areas captured by our search strategy. However, we also observe evidence that this depends in part on research methodology, with candidate gene studies showing very low average power and studies using cognitive/behavioural measures showing high average power. This warrants further investigation. PMID:28386409

Heterodyne laser diagnostic system

DOEpatents

Globig, Michael A.; Johnson, Michael A.; Wyeth, Richard W.

1990-01-01

The heterodyne laser diagnostic system includes, in one embodiment, an average power pulsed laser optical spectrum analyzer for determining the average power of the pulsed laser. In another embodiment, the system includes a pulsed laser instantaneous optical frequency measurement for determining the instantaneous optical frequency of the pulsed laser.

18 CFR 301.6 - Appendix 1 instructions.

Code of Federal Regulations, 2013 CFR

2013-04-01

..., DEPARTMENT OF ENERGY REGULATIONS FOR FEDERAL POWER MARKETING ADMINISTRATIONS AVERAGE SYSTEM COST METHODOLOGY... 4: Average System Cost (f) The filing Utility must reference and attach work papers, documentation... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Appendix 1 instructions...

18 CFR 301.6 - Appendix 1 instructions.

Code of Federal Regulations, 2011 CFR

2011-04-01

..., DEPARTMENT OF ENERGY REGULATIONS FOR FEDERAL POWER MARKETING ADMINISTRATIONS AVERAGE SYSTEM COST METHODOLOGY... 4: Average System Cost (f) The filing Utility must reference and attach work papers, documentation... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Appendix 1 instructions...

18 CFR 301.6 - Appendix 1 instructions.

Code of Federal Regulations, 2014 CFR

2014-04-01

..., DEPARTMENT OF ENERGY REGULATIONS FOR FEDERAL POWER MARKETING ADMINISTRATIONS AVERAGE SYSTEM COST METHODOLOGY... 4: Average System Cost (f) The filing Utility must reference and attach work papers, documentation... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Appendix 1 instructions...

18 CFR 301.6 - Appendix 1 instructions.

Code of Federal Regulations, 2012 CFR

2012-04-01

..., DEPARTMENT OF ENERGY REGULATIONS FOR FEDERAL POWER MARKETING ADMINISTRATIONS AVERAGE SYSTEM COST METHODOLOGY... 4: Average System Cost (f) The filing Utility must reference and attach work papers, documentation... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Appendix 1 instructions...

Distinguished Lecture Series - Balancing the Energy & Climate Budget

ScienceCinema

None

2017-12-09

The average American uses 11400 Watts of power continuously. This is the equivalent of burning 114 x100 Watt light bulbs, all the time. The average person globally uses 2255 Watts of power, or a little less than 23 x100 Watt light bulbs.

1.5-μm high-average power laser amplifier using a Er,Yb:glass planar waveguide for coherent Doppler lidar

NASA Astrophysics Data System (ADS)

Sakimura, Takeshi; Watanabe, Yojiro; Ando, Toshiyuki; Kameyama, Shumpei; Asaka, Kimio; Tanaka, Hisamichi; Yanagisawa, Takayuki; Hirano, Yoshihito; Inokuchi, Hamaki

2012-11-01

We have developed a 1.5-μm eye-safe wavelength high average power laser amplifier using an Er,Yb:glass planar waveguide for coherent Doppler LIDAR. Large cooling surface of the planar waveguide enabled high average power pumping for Er,Yb:glass which has low thermal fracture limit. Nonlinear effects are suppressed by the large beam size which is designed by the waveguide thickness and the beam width of the planar direction. Multi-bounce optical path configuration and high-intensity pumping provide high-gain and high-efficient operation using three-level laser material. With pulsed operation, the maximum pulse energy of 1.9 mJ was achieved at the repetition rate of 4 kHz. Output average power of the amplified signal was 7.6W with the amplified gain of more than 20dB. This amplifier is suitable for coherent Doppler LIDAR to enhance the measurable range.

Future Market Share of Space Solar Electric Power Under Open Competition

NASA Astrophysics Data System (ADS)

Smith, S. J.; Mahasenan, N.; Clarke, J. F.; Edmonds, J. A.

2002-01-01

This paper assesses the value of Space Solar Power deployed under market competition with a full suite of alternative energy technologies over the 21st century. Our approach is to analyze the future energy system under a number of different scenarios that span a wide range of possible future demographic, socio-economic, and technological developments. Scenarios both with, and without, carbon dioxide concentration stabilization policies are considered. We use the comprehensive set of scenarios created for the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios (Nakicenovic and Swart 2000). The focus of our analysis will be the cost of electric generation. Cost is particularly important when considering electric generation since the type of generation is, from a practical point of view, largely irrelevant to the end-user. This means that different electricity generation technologies must compete on the basis of price. It is important to note, however, that even a technology that is more expensive than average can contribute to the overall generation mix due to geographical and economic heterogeneity (Clarke and Edmonds 1993). This type of competition is a central assumption of the modeling approach used here. Our analysis suggests that, under conditions of full competition of all available technologies, Space Solar Power at 7 cents per kW-hr could comprise 5-10% of global electric generation by the end of the century, with a global total generation of 10,000 TW-hr. The generation share of Space Solar Power is limited due to competition with lower-cost nuclear, biomass, and terrestrial solar PV and wind. The imposition of a carbon constraint does not significantly increase the total amount of power generated by Space Solar Power in cases where a full range of advanced electric generation technologies are also available. Potential constraints on the availability of these other electric generation options can increase the amount of electricity generated by Space Solar Power. In agreement with previous work on this subject, we note that launch costs are a significant impediment for the widespread implementation of Space Solar Power. KEY WORDS: space satellite power, advanced electric generation, electricity price, climate change

Area-Specific Marginal Costing for Electric Utilities: a Case Study of Transmission and Distribution Costs

NASA Astrophysics Data System (ADS)

Orans, Ren

1990-10-01

Existing procedures used to develop marginal costs for electric utilities were not designed for applications in an increasingly competitive market for electric power. The utility's value of receiving power, or the costs of selling power, however, depend on the exact location of the buyer or seller, the magnitude of the power and the period of time over which the power is used. Yet no electric utility in the United States has disaggregate marginal costs that reflect differences in costs due to the time, size or location of the load associated with their power or energy transactions. The existing marginal costing methods used by electric utilities were developed in response to the Public Utilities Regulatory Policy Act (PURPA) in 1978. The "ratemaking standards" (Title 1) established by PURPA were primarily concerned with the appropriate segmentation of total revenues to various classes-of-service, designing time-of-use rating periods, and the promotion of efficient long-term resource planning. By design, the methods were very simple and inexpensive to implement. Now, more than a decade later, the costing issues facing electric utilities are becoming increasingly complex, and the benefits of developing more specific marginal costs will outweigh the costs of developing this information in many cases. This research develops a framework for estimating total marginal costs that vary by the size, timing, and the location of changes in loads within an electric distribution system. To complement the existing work at the Electric Power Research Institute (EPRI) and Pacific Gas and Electric Company (PGandE) on estimating disaggregate generation and transmission capacity costs, this dissertation focuses on the estimation of distribution capacity costs. While the costing procedure is suitable for the estimation of total (generation, transmission and distribution) marginal costs, the empirical work focuses on the geographic disaggregation of marginal costs related to electric utility distribution investment. The study makes use of data from an actual distribution planning area, located within PGandE's service territory, to demonstrate the important characteristics of this new costing approach. The most significant result of this empirical work is that geographic differences in the cost of capacity in distribution systems can be as much as four times larger than the current system average utility estimates. Furthermore, lumpy capital investment patterns can lead to significant cost differences over time.

Occupational exposure to gases, polycyclic aromatic hydrocarbons and volatile organic compounds in biomass-fired power plants.

PubMed

Jumpponen, M; Rönkkömäki, H; Pasanen, P; Laitinen, J

2013-01-01

The combustion of fuels produces air pollutants in the form of gases, organic compounds, and particulate matter. However, although the environmental aspect of these agents has been examined, workers' exposure to them is still a neglected issue. The purpose of this study was to measure maintenance and ash removal workers' multiple exposures to gases, volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) during their work tasks in biomass-fired power plants. Our hygienic measurements revealed that carbon monoxide, nitric oxide, ammonia and sulfur dioxide were the most common gases that the workers were exposed to during their tasks. Their average concentrations were 0.45 ppm, 0.06 ppm, 0.11 ppm and 0.42 ppm, respectively. Phenanthrene and naphthalene were the most prominent PAHs. At the same sampling points, the most commonly found VOCs were aromatic and aliphatic hydrocarbons and turpentines. The calculated total PAH concentrations were less than 7% of benzo[a]pyrene's eight-hour occupational exposure limit, and the total VOC concentrations were below the Finnish reference value for the normal industrial level in all measured work tasks. The most evident health effect caused by multiple exposures to gases was upper respiratory track irritation, followed by the disruption of oxygen transport, and finally central nervous system disorders. We recommend powered air respirators with ABEK+P3 cartridges and carbon monoxide gas detectors as the minimum requirement for those working inside biomass-fired power plant boilers, and compressed air breathing apparatus as the best form of protection. Copyright © 2012 Elsevier Ltd. All rights reserved.

Development of on-line laser power monitoring system

NASA Astrophysics Data System (ADS)

Ding, Chien-Fang; Lee, Meng-Shiou; Li, Kuan-Ming

2016-03-01

Since the laser was invented, laser has been applied in many fields such as material processing, communication, measurement, biomedical engineering, defense industries and etc. Laser power is an important parameter in laser material processing, i.e. laser cutting, and laser drilling. However, the laser power is easily affected by the environment temperature, we tend to monitor the laser power status, ensuring there is an effective material processing. Besides, the response time of current laser power meters is too long, they cannot measure laser power accurately in a short time. To be more precisely, we can know the status of laser power and help us to achieve an effective material processing at the same time. To monitor the laser power, this study utilize a CMOS (Complementary metal-oxide-semiconductor) camera to develop an on-line laser power monitoring system. The CMOS camera captures images of incident laser beam after it is split and attenuated by beam splitter and neutral density filter. By comparing the average brightness of the beam spots and measurement results from laser power meter, laser power can be estimated. Under continuous measuring mode, the average measuring error is about 3%, and the response time is at least 3.6 second shorter than thermopile power meters; under trigger measuring mode which enables the CMOS camera to synchronize with intermittent laser output, the average measuring error is less than 3%, and the shortest response time is 20 millisecond.

High-average-power CTH:YAG for the medical environment

NASA Astrophysics Data System (ADS)

Wright, Sidney P.; Adamkiewicz, Edward J.; Moulton, Peter F.

1992-06-01

Medical procedures such as arthroscopy have placed increasing demands on the output performance of the CTH:YAG laser at 2.1 micrometers . Intensive research has been conducted to improve the average power, pulse energies, and rep rates while reducing any failure mechanisms. The results of this work is reported along with a discussion of the important engineering parameters concerning the design of a high power medical CTH:YAG laser.

Electrodynamic Tethers. 1: Power Generator in LEO. 2: Thrust for Propulsion and Power Storage

NASA Technical Reports Server (NTRS)

Mccoy, J. E.

1984-01-01

An electrodynamic tether consists of a long insulated wire in space whose orbital motion cuts across lines of magnetic flux to produce an induce voltage that in typical low orbits averages about 200 v/km. Such a system should be capable of generating substantial electrical power, at the expense of IXB drag acting on its orbital energy. If a reverse current is driven against the induced voltage, the system should act as a motor producing IXB thrust. A reference system was designed, capable of generating 20 KW of power into an electrical load located anywhere along the wire at the expense of 2.6N (20,000 J/sec) drag on the wire. In an ideal system, the conversion between mechanical and electrical energy would reach 100% efficiency. In the actual system part of the 20 KW is lost to internal resistance of the wire, plasma and ionosphere, while the drag force is increased by residual air drag. The 20 KW PMG system as designed is estimated to provide 18.7 KW net power to the load at total drag loss of 20.4 KJ/sec, or an overall efficiency of 92%. Similar systems using heavier wire appear capable of producing power levels in excess of 1 Megawatt at voltages of 2-4 KV, with conversion efficiency between mechanical and electrical power better than 95%. The hollow cathode based system should be readily reversible from generator to motor operation by driving a reverse current using onboard power.

Fiber-based tunable repetition rate source for deep tissue two-photon fluorescence microscopy.

PubMed

Charan, Kriti; Li, Bo; Wang, Mengran; Lin, Charles P; Xu, Chris

2018-05-01

Deep tissue multiphoton imaging requires high peak power to enhance signal and low average power to prevent thermal damage. Both goals can be advantageously achieved through laser repetition rate tuning instead of simply adjusting the average power. We show that the ideal repetition rate for deep two-photon imaging in the mouse brain is between 1 and 10 MHz, and we present a fiber-based source with an arbitrarily tunable repetition rate within this range. The performance of the new source is compared to a mode-locked Ti:Sapphire (Ti:S) laser for in vivo imaging of mouse brain vasculature. At 2.5 MHz, the fiber source requires 5.1 times less average power to obtain the same signal as a standard Ti:S laser operating at 80 MHz.

Unraveling resistive versus collisional contributions to relativistic electron beam stopping power in cold-solid and in warm-dense plasmas

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

Vauzour, B.; Laboratoire d'Optique Appliquée, ENSTA-CNRS-Ecole Polytechnique, UMR 7639, 91761 Palaiseau; Debayle, A.

2014-03-15

We present results on laser-driven relativistic electron beam propagation through aluminum samples, which are either solid and cold or compressed and heated by laser-induced shock. A full numerical description of fast electron generation and transport is found to reproduce the experimental absolute K{sub α} yield and spot size measurements for varying target thicknesses, and to sequentially quantify the collisional and resistive electron stopping powers. The results demonstrate that both stopping mechanisms are enhanced in compressed Al samples and are attributed to the increase in the medium density and resistivity, respectively. For the achieved time- and space-averaged electronic current density, 〈j{submore » h}〉∼8×10{sup 10} A/cm{sup 2} in the samples, the collisional and resistive stopping powers in warm and compressed Al are estimated to be 1.5 keV/μm and 0.8 keV/μm, respectively. By contrast, for cold and solid Al, the corresponding estimated values are 1.1 keV/μm and 0.6 keV/μm. Prospective numerical simulations involving higher j{sub h} show that the resistive stopping power can reach the same level as the collisional one. In addition to the effects of compression, the effect of the transient behavior of the resistivity of Al during relativistic electron beam transport becomes progressively more dominant, and for a significantly high current density, j{sub h}∼10{sup 12} A/cm{sup 2}, cancels the difference in the electron resistive stopping power (or the total stopping power in units of areal density) between solid and compressed samples. Analytical calculations extend the analysis up to j{sub h}=10{sup 14} A/cm{sup 2} (representative of the full-scale fast ignition scenario of inertial confinement fusion), where a very rapid transition to the Spitzer resistivity regime saturates the resistive stopping power, averaged over the electron beam duration, to values of ∼1 keV/μm.« less

Numerical calculations of non-inductive current driven by microwaves in JET

NASA Astrophysics Data System (ADS)

Kirov, K. K.; Baranov, Yu; Mailloux, J.; Nave, M. F. F.; Contributors, JET

2016-12-01

Recent studies at JET focus on analysis of the lower hybrid (LH) wave power absorption and current drive (CD) calculations by means of a new ray tracing (RT)/Fokker-Planck (FP) package. The RT code works in real 2D geometry accounting for the plasma boundary and the launcher shape. LH waves with different parallel refractive index, {{N}\\parallel} , spectra in poloidal direction can be launched thus simulating authentic antenna spectrum with rows fed by different combinations of klystrons. Various FP solvers were tested most advanced of which is a relativistic bounce averaged FP code. LH wave power deposition profiles from the new RT/FP code were compared to the experimental results from electron cyclotron emission (ECE) analysis of pulses at 3.4 T low and high density. This kind of direct comparison between power deposition profiles from experimental ECE data and numerical model were carried out for the first time for waves in the LH range of frequencies. The results were in a reasonable agreement with experimental data at lower density, line averaged values of {{n}\\text{e}}≈ 2.4× {{10}19} {{\\text{m}}-3} . At higher density, {{n}\\text{e}}≈ 3× {{10}19} {{\\text{m}}-3} , the code predicted larger on-axis LH power deposition, which is inconsistent with the experimental observations. Both calculations were unable to produce LH wave absorption at the plasma periphery, which contradicts to the analysis of the ECE data and possible sources of these discrepancies have been briefly discussed in the paper. The code was also used to calculate the LH power deposition and CD profiles for the low-density preheat phase of JET’s advanced tokamak (AT) scenario. It was found that as the density evolves from hollow to flat and then to a more peaked profile the LH power and driven current move inward i.e. towards the plasma axis. A total driven current of about 70 kA for 1 MW of launched LH power was predicted in these conditions.

Carrier envelope offset frequency detection and stabilization of a diode-pumped mode-locked Ti:sapphire laser.

PubMed

Gürel, Kutan; Wittwer, Valentin J; Hakobyan, Sargis; Schilt, Stéphane; Südmeyer, Thomas

2017-03-15

We demonstrate the first diode-pumped Ti:sapphire laser frequency comb. It is pumped by two green laser diodes with a total pump power of 3 W. The Ti:sapphire laser generates 250 mW of average output power in 61-fs pulses at a repetition rate of 216 MHz. We generated an octave-spanning supercontinuum spectrum in a photonic-crystal fiber and detected the carrier envelope offset (CEO) frequency in a standard f-to-2f interferometer setup. We stabilized the CEO-frequency through direct current modulation of one of the green pump diodes with a feedback bandwidth of 55 kHz limited by the pump diode driver used in this experiment. We achieved a reduction of the CEO phase noise power spectral density by 140 dB at 1 Hz offset frequency. An advantage of diode pumping is the ability for high-bandwidth modulation of the pump power via direct current modulation. After this experiment, we studied the modulation capabilities and noise properties of green pump laser diodes with improved driver electronics. The current-to-output-power modulation transfer function shows a bandwidth larger than 1 MHz, which should be sufficient to fully exploit the modulation bandwidth of the Ti:sapphire gain for CEO stabilization in future experiments.

Supplementation with a Polyphenol-Rich Extract, PerfLoad®, Improves Physical Performance during High-Intensity Exercise: A Randomized, Double Blind, Crossover Trial

PubMed Central

Cases, Julien; Romain, Cindy; Marín-Pagán, Cristian; Chung, Linda H.; Rubio-Pérez, José Miguel; Laurent, Caroline; Gaillet, Sylvie; Prost-Camus, Emmanuelle; Prost, Michel; Alcaraz, Pedro E.

2017-01-01

Workout capacity is energy-production driven. To produce peak metabolic power outputs, the organism predominantly relies more on anaerobic metabolism, but this undoubtedly has a negative and limiting impact on muscle function and performance. The aim of the study was to evaluate if an innovative polyphenol-based food supplement, PerfLoad®, was able to improve metabolic homeostasis and physical performance during high-intensity exercises under anaerobic conditions. The effect of a supplementation has been investigated on fifteen recreationally-active male athletes during a randomized, double-blind and crossover clinical investigation. The Wingate test, an inducer of an unbalanced metabolism associated to oxidative stress, was used to assess maximum anaerobic power during a high-intensity exercise on a cycle ergometer. Supplementation with PerfLoad® correlated with a significant increase in total power output (5%), maximal peak power output (3.7%), and average power developed (5%), without inducing more fatigue or greater heart rate. Instead, oxidative homeostasis was stabilized in supplemented subjects. Such results demonstrated that PerfLoad® is a natural and efficient solution capable of, similarly to training benefits, helping athletes to improve their physical performance, while balancing their metabolism and reducing exercise-induced oxidative stress. PMID:28441760

50 kWp Photovoltaic Concentrator Application Experiment, Phase I. Final report, 1 June 1978-28 February 1979

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

Maget, H.J.R.

1979-06-15

This program consists of a design study and component development for an experimental 50-kWp photovoltaic concentrator system to supply power to the San Ramon substation of the Pacific Gas and Electric Company. The photovoltaic system is optimized to produce peaking power to relieve the air conditioning load on the PG and E system during summer afternoons; and would therefore displace oil-fired power generation capacity. No electrical storage is required. The experiment would use GaAs concentrator cells with point-focus fresnel lenses operating at 400X, in independent tracking arrays of 440 cells each, generating 3.8 kWp. Fourteen arrays, each 9 feet bymore » 33 feet, are connected electrically in series to generate the 50 kWp. The high conversion efficiency possible with GaAs concentrator cells results in a projected annual average system efficiency (AC electric power output to sunlight input) of better than 15%. The capability of GaAs cells for high temperature operation made possible the design of a total energy option, whereby thermal power from selected arrays could be used to heat and cool the control center for the installation. System design and analysis, fabrication and installation, environmental assessment, and cost projections are described in detail. (WHK)« less

Energy Analysis and Environmental Impacts of Hybrid Giant Napier (Pennisetum Hydridum) Direct-fired Power Generation in South China

NASA Astrophysics Data System (ADS)

Liao, Yanfen; Fang, Hailin; Zhang, Hengjin; Yu, Zhaosheng; Liu, Zhichao; Ma, Xiaoqian

2017-05-01

To meet with the demand of energy conservation and emission reduction policies, the method of life cycle assessment (LCA) was used to assess the feasibility of Hybrid Giant Napier (HGN) direct-fired power generation in this study. The entire life cycle is consisted of five stages (cultivation and harvesting, transportation, drying and comminuting, direct-fired power generation, constructing and decommissioning of biomass power plant). Analytical results revealed that to generate 10000kWh electricity, 10.925 t of customized HGN fuel (moisture content: 30 wt%) and 6659.430 MJ of energy were required. The total environmental impact potential was 0.927 PET2010 (person equivalents, targeted, in 2010) and the global warming (GW), acidification (AC), and nutrient (NE) emissions were 339.235 kg CO2-eq, 22.033 kg SO2-eq, and 25.486 kg NOx-eq respectively. The effect of AC was the most serious among all calculated category impacts. The energy requirements and environmental impacts were found to be sensitive to single yield, average transport distance, cutting frequency, and moisture content. The results indicated that HGN direct-fired power generation accorded well with Chinese energy planning; in addition, HGN proved to be a promising contribution to reducing non-renewable energy consumption and had encouraging prospects as a renewable energy plant.

NATIONAL GEODATABASE OF TIDAL STREAM POWER RESOURCE IN USA

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

Smith, Brennan T; Neary, Vincent S; Stewart, Kevin M

2012-01-01

A geodatabase of tidal constituents is developed to present the regional assessment of tidal stream power resource in the USA. Tidal currents are numerically modeled with the Regional Ocean Modeling System (ROMS) and calibrated with the available measurements of tidal current speeds and water level surfaces. The performance of the numerical model in predicting the tidal currents and water levels is assessed by an independent validation. The geodatabase is published on a public domain via a spatial database engine with interactive tools to select, query and download the data. Regions with the maximum average kinetic power density exceeding 500 W/m2more » (corresponding to a current speed of ~1 m/s), total surface area larger than 0.5 km2 and depth greater than 5 m are defined as hotspots and documented. The regional assessment indicates that the state of Alaska (AK) has the largest number of locations with considerably high kinetic power density, followed by, Maine (ME), Washington (WA), Oregon (OR), California (CA), New Hampshire (NH), Massachusetts (MA), New York (NY), New Jersey (NJ), North and South Carolina (NC, SC), Georgia (GA), and Florida (FL).« less

An Evaluation of Functional Sit-to-Stand Power in Cohorts of Healthy Adults Aged 18-97 Years.

PubMed

Glenn, Jordan M; Gray, Michelle; Vincenzo, Jennifer; Paulson, Sally; Powers, Melissa

2017-04-01

This investigation examined differences in functional sit-to-stand power/velocity between cohorts of adults aged 18-97 years. This study included 264 healthy adults classified into four cohorts (18-40, C1; 60-69, C2; 70-79, C2; ≥ 80, C4). Participants completed the sit-to-stand task five times. Power and velocity were measured via the TENDO power analyzer. Absolute average power was maintained from C1-C3, but decreased (p < .01) in C4. Absolute peak power decreased between C1-C2 (p < .01), was similar between C2-C3, and decreased in C4 (p < .01). Relative (to body weight) average and peak power decreased between C1-C2 (p < .01), was similar between C2-C3, and decreased in C4 (p < .01). Average velocity was similar between C1 and C2, but decreased in C3 (p < .01) and C4 (p < .01), respectively. Peak velocity was significantly different between all cohorts (p < .01). Declines in functional power may plateau during the seventh and eighth decades, accelerating after 80 years.

Measured radiofrequency exposure during various mobile-phone use scenarios.

PubMed

Kelsh, Michael A; Shum, Mona; Sheppard, Asher R; McNeely, Mark; Kuster, Niels; Lau, Edmund; Weidling, Ryan; Fordyce, Tiffani; Kühn, Sven; Sulser, Christof

2011-01-01

Epidemiologic studies of mobile phone users have relied on self reporting or billing records to assess exposure. Herein, we report quantitative measurements of mobile-phone power output as a function of phone technology, environmental terrain, and handset design. Radiofrequency (RF) output data were collected using software-modified phones that recorded power control settings, coupled with a mobile system that recorded and analyzed RF fields measured in a phantom head placed in a vehicle. Data collected from three distinct routes (urban, suburban, and rural) were summarized as averages of peak levels and overall averages of RF power output, and were analyzed using analysis of variance methods. Technology was the strongest predictor of RF power output. The older analog technology produced the highest RF levels, whereas CDMA had the lowest, with GSM and TDMA showing similar intermediate levels. We observed generally higher RF power output in rural areas. There was good correlation between average power control settings in the software-modified phones and power measurements in the phantoms. Our findings suggest that phone technology, and to a lesser extent, degree of urbanization, are the two stronger influences on RF power output. Software-modified phones should be useful for improving epidemiologic exposure assessment.

The study of atmospheric CO pollution over the center of Moscow in autumn period

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

Fokeeva, E.V.; Pekour, M.S.

1996-12-31

The results of CO near-ground concentration measurements are presented which were taken by virtue of electrochemical method at the center of Moscow during one autumn month in 1993. Simultaneous measurements were performed of the total column content of CO over Moscow making use of sun radiation absorption detection in the infrared (in the wavelength range of 4.6 mcm). To determine an urban increment of CO content over regional background the data of analogous measurements were used which were collected in the rural suburb 45 km west from Moscow center One-hour averaged near-ground CO concentration were in the limits 0.4 tomore » 5.8 mg/m{sup 3}, and an average total column CO content vary from 0.09 to 0.167 atm*cm. The measurements were accompanied by acoustic sounding of the atmosphere boundary layer with the use of three component Doppler SODAR. The peculiarities of average and concrete diurnal variation of near-ground CO concentrations can well be interpreted by virtue of SODAR data indicating the type of stratification, the mixing height and the wind velocity during a whole day. Comparison and analysis are performed of the average diurnal variations of near-ground CO concentration in autumn and summer periods in account to the occurrence frequency of surface inversion within selected periods. Almost complete coincidence has been found of the shape of CO concentration diurnal variations with those of NO and soot. An estimate of specific CO source power in the city is performed in account to the data on the mixing height and wind velocity mean within a layer of 250 m.« less

Costs of informal nursing care for patients with neurologic disorders: A systematic review.

PubMed

Diederich, Freya; König, Hans-Helmut; Mietzner, Claudia; Brettschneider, Christian

2018-01-02

To systematically review the economic burden of informal nursing care (INC), often called informal care, caused by multiple sclerosis (MS), Parkinson disease (PD), and epilepsy, with special attention to disease severity. We systematically searched MEDLINE, PsycINFO, and NHS Economic Evaluation Database for articles on the cost of illness of the diseases specified. Title, abstract, and full-text review were conducted in duplicate by 2 researchers. The distribution of hours and costs of INC were extracted and used to compare the relevance of INC across included diseases and disease severity. Seventy-one studies were included (44 on MS, 17 on PD, and 10 on epilepsy). Studies on epilepsy reported an average of 2.3-54.5 monthly hours of INC per patient. For PD, average values of 42.9-145.9 hours and for MS average values of 9.2-249 hours per patient per month were found. In line with utilized hours, costs of INC were lowest for epilepsy (interquartile range [IQR] 229-1,466 purchasing power parity US dollars [PPP-USD]) and similar for MS (IQR 4,454-11,222 PPP-USD) and PD (IQR 1,440-7,117 PPP-USD). In addition, costs of INC increased with disease severity and accounted for 38% of total health care costs in severe MS stages on average. The course of diseases and disease severity matter for the amount of INC used by patients. For each of the neurologic disorders, an increase in the costs of INC, due to increasing disease severity, considerably contributes to the rise in total health care costs. Copyright © 2017 American Academy of Neurology.

Recent trends in power system reliability and implications for evaluating future investments in resiliency

DOE PAGES

Larsen, Peter H.; LaCommare, Kristina H.; Eto, Joseph H.; ...

2016-10-27

Here, this study examines the relationship between annual changes in electricity reliability reported by a large cross-section of U.S. electricity distribution utilities over a period of 13 years and a broad set of potential explanatory variables, including weather and utility characteristics. We find statistically significant correlations between the average number of power interruptions experienced annually and above average wind speeds, precipitation, lightning strikes, and a measure of population density: customers per line mile. We also find significant relationships between the average number of minutes of power interruptions experienced and above average wind speeds, precipitation, cooling degree-days, and one strategy usedmore » to mitigate the impacts of severe weather: the amount of underground transmission and distribution line miles. Perhaps most importantly, we find a significant time trend of increasing annual average number of minutes of power interruptions over time—especially when interruptions associated with extreme weather are included. Lastly, the research method described in this analysis can provide a basis for future efforts to project long-term trends in reliability and the associated benefits of strategies to improve grid resiliency to severe weather—both in the U.S. and abroad.« less

Fundamental formulae for wave-energy conversion

PubMed Central

Falnes, Johannes; Kurniawan, Adi

2015-01-01

The time-average wave power that is absorbed from an incident wave by means of a wave-energy conversion (WEC) unit, or by an array of WEC units—i.e. oscillating immersed bodies and/or oscillating water columns (OWCs)—may be mathematically expressed in terms of the WEC units' complex oscillation amplitudes, or in terms of the generated outgoing (diffracted plus radiated) waves, or alternatively, in terms of the radiated waves alone. Following recent controversy, the corresponding three optional expressions are derived, compared and discussed in this paper. They all provide the correct time-average absorbed power. However, only the first-mentioned expression is applicable to quantify the instantaneous absorbed wave power and the associated reactive power. In this connection, new formulae are derived that relate the ‘added-mass’ matrix, as well as a couple of additional reactive radiation-parameter matrices, to the difference between kinetic energy and potential energy in the water surrounding the immersed oscillating WEC array. Further, a complex collective oscillation amplitude is introduced, which makes it possible to derive, by a very simple algebraic method, various simple expressions for the maximum time-average wave power that may be absorbed by the WEC array. The real-valued time-average absorbed power is illustrated as an axisymmetric paraboloid defined on the complex collective-amplitude plane. This is a simple illustration of the so-called ‘fundamental theorem for wave power’. Finally, the paper also presents a new derivation that extends a recently published result on the direction-average maximum absorbed wave power to cases where the WEC array's radiation damping matrix may be singular and where the WEC array may contain OWCs in addition to oscillating bodies. PMID:26064612

T700 Blisk and Impeller Manufacturing Process Development Program.

DTIC Science & Technology

1979-11-01

700(40) Reworked Media Temperature - 790 F Average Media Pressure - 200 psi Total Cycles (Test No. 1) - 40 Total Cycles (Test No. 2) - 20 Total Time...36A(73), - 700(40" Media Temperature - 80F Average Media Pressure - 150 psi Total Cycles - 52 Total Time - 95 Minutes Some difficulty was...61)-36A(73)-700( 4O)Media Temperature - 79OF average Media Pressure - 200 psi Time - 40 cycles - 72 minutes Time - 60 cycles - 109 minutes Time - 80

Energy and macronutrient intake of a female vegan cyclist during an 8-day mountain bike stage race

PubMed Central

Kornexl, Elmar

2014-01-01

This report describes the dietary intake of a vegan mountain biker (height, 161 cm; weight, 49.6 kg; body mass index, 19.1 kg/m2; relative peak power output, 4.6 W/kg) during the Transalp Challenge 2004 (altitude climbed, 22,500 m; total distance, 662 km), illustrating an aggressive dietary strategy that allowed the cyclist to be competitive. She finished the 8-stage event in 42 hours (mixed category, rank 16; 514 minutes behind the winners of this category), cycling with an average heart rate of 79.5% of laboratory-determined maximum, spending 892 minutes and 1627 minutes at intensities below and above 80%, respectively. During racing, the consumption of energy was 69.3 MJ (1.65 MJ/h), 65.76 MJ from carbohydrates (92 g/h), which was 35% of calories and 40% of carbohydrate total intake, and the fluid ingested was 3 L/day (570 mL/h), 55% of the total fluid consumed. PMID:24381405

Energy and macronutrient intake of a female vegan cyclist during an 8-day mountain bike stage race.

PubMed

Wirnitzer, Katharina C; Kornexl, Elmar

2014-01-01

This report describes the dietary intake of a vegan mountain biker (height, 161 cm; weight, 49.6 kg; body mass index, 19.1 kg/m(2); relative peak power output, 4.6 W/kg) during the Transalp Challenge 2004 (altitude climbed, 22,500 m; total distance, 662 km), illustrating an aggressive dietary strategy that allowed the cyclist to be competitive. She finished the 8-stage event in 42 hours (mixed category, rank 16; 514 minutes behind the winners of this category), cycling with an average heart rate of 79.5% of laboratory-determined maximum, spending 892 minutes and 1627 minutes at intensities below and above 80%, respectively. During racing, the consumption of energy was 69.3 MJ (1.65 MJ/h), 65.76 MJ from carbohydrates (92 g/h), which was 35% of calories and 40% of carbohydrate total intake, and the fluid ingested was 3 L/day (570 mL/h), 55% of the total fluid consumed.

Comparison of dwarf bamboos (Indocalamus sp.) leaf parameters to determine relationship between spatial density of plants and total leaf area per plant.

PubMed

Shi, Pei-Jian; Xu, Qiang; Sandhu, Hardev S; Gielis, Johan; Ding, Yu-Long; Li, Hua-Rong; Dong, Xiao-Bo

2015-10-01

The relationship between spatial density and size of plants is an important topic in plant ecology. The self-thinning rule suggests a -3/2 power between average biomass and density or a -1/2 power between stand yield and density. However, the self-thinning rule based on total leaf area per plant and density of plants has been neglected presumably because of the lack of a method that can accurately estimate the total leaf area per plant. We aimed to find the relationship between spatial density of plants and total leaf area per plant. We also attempted to provide a novel model for accurately describing the leaf shape of bamboos. We proposed a simplified Gielis equation with only two parameters to describe the leaf shape of bamboos one model parameter represented the overall ratio of leaf width to leaf length. Using this method, we compared some leaf parameters (leaf shape, number of leaves per plant, ratio of total leaf weight to aboveground weight per plant, and total leaf area per plant) of four bamboo species of genus Indocalamus Nakai (I. pedalis (Keng) P.C. Keng, I. pumilus Q.H. Dai and C.F. Keng, I. barbatus McClure, and I. victorialis P.C. Keng). We also explored the possible correlation between spatial density and total leaf area per plant using log-linear regression. We found that the simplified Gielis equation fit the leaf shape of four bamboo species very well. Although all these four species belonged to the same genus, there were still significant differences in leaf shape. Significant differences also existed in leaf area per plant, ratio of leaf weight to aboveground weight per plant, and leaf length. In addition, we found that the total leaf area per plant decreased with increased spatial density. Therefore, we directly demonstrated the self-thinning rule to improve light interception.

Inclusion of cool roofs in nonresidential Title 24 prescriptive requirements

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

Levinson, Ronnen; Akbari, Hashem; Konopacki, Steve

2002-12-15

Roofs that have high solar reflectance (high ability to reflect sunlight) and high thermal emittance (high ability to radiate heat) tend to stay cool in the sun. The same is true of low-emittance roofs with exceptionally high solar reflectance. Substituting a cool roof for a noncool roof tends to decrease cooling electricity use, cooling power demand, and cooling-equipment capacity requirements, while slightly increasing heating energy consumption. Cool roofs can also lower the ambient air temperature in summer, slowing ozone formation and increasing human comfort. DOE-2.1E building energy simulations indicate that use of a cool roofing material on a prototypical Californiamore » nonresidential building with a low-sloped roof yields average annual cooling energy savings of approximately 300 kWh/1000 ft2 [3.2 kWh/m2], average annual natural gas deficits of 4.9 therm/1000 ft2 [5.6 MJ/m2], average source energy savings of 2.6 MBTU/1000 ft2 [30 MJ/m2], and average peak power demand savings of 0. 19 kW/1000 ft2 [2.1 W/m2]. The 15-year net present value (NPV) of energy savings averages $450/1000 ft2 [$4.90/m2] with time dependent valuation (TDV), and $370/1000 ft2 [$4.00/m2] without TDV. When cost savings from downsizing cooling equipment are included, the average total savings (15-year NPV + equipment savings) rises to $550/1000 ft2 [$5.90/m2] with TDV, and to $470/1000 ft2 [$5.00/m2] without TDV. Total savings range from 0.18 to 0.77 $/ft2 [1.90 to 8.30 $/m2] with TDV, and from 0.16 to 0.66 $/ft2 [1.70 to 7.10 $/m2] without TDV, across California's 16 climate zones. The typical cost premium for a cool roof is 0.00 to 0.20 $/ft2 [0.00 to 2.20 $/m2]. Cool roofs with premiums up to $0.20/ft2 [$2.20/m2] are expected to be cost effective in climate zones 2 through 16; those with premiums not exceeding $0.18/ft2 [$1.90/m2] are expected to be also cost effective in climate zone 1. Hence, this study recommends that the year-2005 California building energy efficiency code (Title 24, Pa rt 6 of the California Code of Regulations) for nonresidential buildings with low-sloped roofs include a cool-roof prescriptive requirement in all California climate zones. Buildings with roofs that do not meet prescriptive requirements may comply with the code via an ''overall-envelope'' approach (non-metal roofs only), or via a performance approach (all roof types).« less

Measurements of ultrafine particles and other vehicular pollutants inside school buses in South Texas

NASA Astrophysics Data System (ADS)

Zhang, Qunfang; Zhu, Yifang

2010-01-01

Increasing evidence has demonstrated toxic effects of vehicular emitted ultrafine particles (UFPs, diameter < 100 nm), with the highest human exposure usually occurring on and near roadways. Children are particularly at risk due to immature respiratory systems and faster breathing rates. In this study, children's exposure to in-cabin air pollutants, especially UFPs, was measured inside four diesel-powered school buses. Two 1990 and two 2006 model year diesel-powered school buses were selected to represent the age extremes of school buses in service. Each bus was driven on two routine bus runs to study school children's exposure under different transportation conditions in South Texas. The number concentration and size distribution of UFPs, total particle number concentration, PM 2.5, PM 10, black carbon (BC), CO, and CO 2 levels were monitored inside the buses. The average total particle number concentrations observed inside the school buses ranged from 7.3 × 10 3 to 3.4 × 10 4 particles cm -3, depending on engine age and window position. When the windows were closed, the in-cabin air pollutants were more likely due to the school buses' self-pollution. The 1990 model year school buses demonstrated much higher air pollutant concentrations than the 2006 model year ones. When the windows were open, the majority of in-cabin air pollutants came from the outside roadway environment with similar pollutant levels observed regardless of engine ages. The highest average UFP concentration was observed at a bus transfer station where approximately 27 idling school buses were queued to load or unload students. Starting-up and idling generated higher air pollutant levels than the driving state. Higher in-cabin air pollutant concentrations were observed when more students were on board.

Characterizing the relative contributions of large vessels to total ocean noise fields: a case study using the Gerry E. Studds Stellwagen Bank National Marine Sanctuary.

PubMed

Hatch, Leila; Clark, Christopher; Merrick, Richard; Van Parijs, Sofie; Ponirakis, Dimitri; Schwehr, Kurt; Thompson, Michael; Wiley, David

2008-11-01

In 2006, we used the U.S. Coast Guard's Automatic Identification System (AIS) to describe patterns of large commercial ship traffic within a U.S. National Marine Sanctuary located off the coast of Massachusetts. We found that 541 large commercial vessels transited the greater sanctuary 3413 times during the year. Cargo ships, tankers, and tug/tows constituted 78% of the vessels and 82% of the total transits. Cargo ships, tankers, and cruise ships predominantly used the designated Boston Traffic Separation Scheme, while tug/tow traffic was concentrated in the western and northern portions of the sanctuary. We combined AIS data with low-frequency acoustic data from an array of nine autonomous recording units analyzed for 2 months in 2006. Analysis of received sound levels (10-1000 Hz, root-mean-square pressure re 1 microPa +/- SE) averaged 119.5 +/- 0.3 dB at high-traffic locations. High-traffic locations experienced double the acoustic power of less trafficked locations for the majority of the time period analyzed. Average source level estimates (71-141 Hz, root-mean-square pressure re 1 microPa +/- SE) for individual vessels ranged from 158 +/- 2 dB (research vessel) to 186 +/- 2 dB (oil tanker). Tankers were estimated to contribute 2 times more acoustic power to the region than cargo ships, and more than 100 times more than research vessels. Our results indicate that noise produced by large commercial vessels was at levels and within frequencies that warrant concern among managers regarding the ability of endangered whales to maintain acoustic contact within greater sanctuary waters.

Effect of whole-body vibration on center-of-mass movement during standing in children and young adults.

PubMed

Liang, Huaqing; Beerse, Matthew; Ke, Xiang; Wu, Jianhua

2017-05-01

Whole body vibration (WBV) can affect postural control and muscular activation. The purpose of this study was to investigate the center-of-mass (COM) movement of children and young adults before, during, immediately after, and 5min after 40-s WBV in quiet standing. Fourteen young adults (mean age 24.5 years) and fourteen children (mean age 8.1 years) participated in the study. A full-body 35-marker set was placed on the participants and used to calculate COM. Forty-second standing trials were collected before, during, immediately after, and 5min after WBV with an frequency of 28Hz and an amplitude of <1mm. Two visual conditions were provided: eyes-open (EO) and eyes-closed (EC). COM variables included time-domain measures (average velocity, range, sway area and fractal dimension), frequency-domain measures (total power and median frequency), and detrended fluctuation analysis (DFA) scaling exponent in both anterior-posterior (AP) and medial-lateral (ML) directions. Results show that during WBV both children and adults increased average velocity and median frequency, but decreased range and the DFA scaling exponent. Immediately after WBV both groups increased the range, but showed pre-vibration values for most of the COM variables. Comparing to adults, children displayed a higher COM velocity, range, fractal dimension, and total power, but a lower DFA scaling exponent at all phases. The results suggest that both children and adults can quickly adapt their postural control system to WBV and maintain balance during and after vibration. Children display some adult-like postural control during and after WBV; however, their postural development continues into adolescence. Published by Elsevier B.V.

Estimated use of water in the United States - 1950

USGS Publications Warehouse

MacKichan, Kenneth Allen

1951-01-01

An estimated 170,000 million gallons of water was withdrawn from the ground, lakes, or streams each day on the average during 1950 and used on the farms and in the homes, factories, and business establishments of the United States. An additional 1,100,000 million gallons per day was used to generate hydro-power. Water power is the largest user of water; however, irrigation and industry also are large users of both ground and surface water. More surface water was used for industrial purposes than for irrigation, whereas more ground water was used for irrigation than for industrial purposes (fig. 1). The total withdrawal of surface water was considerably in excess of ground-water withdrawal, as shown by figure 1. Large quantities of water were used also for purposes requiring no diversion, such as navigation, waste disposal, recreation, and support of wildlife.

The effect of picosecond laser pulses on redox-dependent processes in mice red blood cells studied in vivo

NASA Astrophysics Data System (ADS)

Voronova, Olga; Gening, Tatyana; Abakumova, Tatyana; Sysolyatin, Aleksey; Zolotovskiy, Igor; Antoneeva, Inna; Ostatochnikov, Vladimir; Gening, Snezhanna

2014-02-01

The study highlights the effect of different modes of in vivo laser irradiation of mice using a PFL8LA laser with λ = 1560 nm, pulse duration of 1,4•10-12 s, peak power of 3,72•103 W and average output power of 20•10-3 W on the lipid peroxidation parameters: conjugated dienes, ketodienes and conjugated trienes, malondialdehyde, Schiff bases and the activity of antioxidant enzymes - catalase, glutathione -S-transferase and superoxide dismutase in erythrocytes and plasma of mice. Two groups of mice received a total dose of 3.8 J/cm2 per group, but the 1st group was irradiated only once, while the 2nd - four times. Significant differences in the parameters of the 1st and 2nd groups indicate different effects of the irradiation modes on redox-dependent processes in red blood cells of mice.

Pulse stretcher

DOEpatents

Horton, J.A.

1994-05-03

Apparatus for increasing the length of a laser pulse to reduce its peak power without substantial loss in the average power of the pulse is disclosed. The apparatus uses a White cell having a plurality of optical delay paths of successively increasing number of passes between the field mirror and the objective mirrors. A pulse from a laser travels through a multi-leg reflective path between a beam splitter and a totally reflective mirror to the laser output. The laser pulse is also simultaneously injected through the beam splitter to the input mirrors of the optical delay paths. The pulses from the output mirrors of the optical delay paths go simultaneously to the laser output and to the input mirrors of the longer optical delay paths. The beam splitter is 50% reflective and 50% transmissive to provide equal attenuation of all of the pulses at the laser output. 6 figures.

A Periodogram of Every Kepler Target and a Common Artifact at ∼80 minutes

NASA Astrophysics Data System (ADS)

Kipping, David

2018-05-01

Studying photometric time series in the frequency domain can serve as a means of detecting rotational modulations, measuring asteroseismic modes and even detecting short-period transiting planets. To our knowledge, there is no prior archive of the NASA Kepler Mission's power spectra and so we present one here to aid the community in searching for such effects. Using DR25 PDC long-cadence Kepler photometry, 2,594,616 individual periodograms are computed using Welch's method with a Nuttall window, where we provide a unique periododogram for each quarter (up to 16) of each star (196,791 in total). Additionally, we normalize the periodograms in the high-frequency end and combine them into channel- and quarter-averaged power spectra to track common instrumental modes occurring onboard the telescope, with a particularly notable feature at ~80 minutes (~200 $\\mu$Hz) observed.

Development of gait segmentation methods for wearable foot pressure sensors.

PubMed

Crea, S; De Rossi, S M M; Donati, M; Reberšek, P; Novak, D; Vitiello, N; Lenzi, T; Podobnik, J; Munih, M; Carrozza, M C

2012-01-01

We present an automated segmentation method based on the analysis of plantar pressure signals recorded from two synchronized wireless foot insoles. Given the strict limits on computational power and power consumption typical of wearable electronic components, our aim is to investigate the capability of a Hidden Markov Model machine-learning method, to detect gait phases with different levels of complexity in the processing of the wearable pressure sensors signals. Therefore three different datasets are developed: raw voltage values, calibrated sensor signals and a calibrated estimation of total ground reaction force and position of the plantar center of pressure. The method is tested on a pool of 5 healthy subjects, through a leave-one-out cross validation. The results show high classification performances achieved using estimated biomechanical variables, being on average the 96%. Calibrated signals and raw voltage values show higher delays and dispersions in phase transition detection, suggesting a lower reliability for online applications.

A Multi-Channel, Flex-Rigid ECoG Microelectrode Array for Visual Cortical Interfacing

PubMed Central

Tolstosheeva, Elena; Gordillo-González, Víctor; Biefeld, Volker; Kempen, Ludger; Mandon, Sunita; Kreiter, Andreas K.; Lang, Walter

2015-01-01

High-density electrocortical (ECoG) microelectrode arrays are promising signal-acquisition platforms for brain-computer interfaces envisioned, e.g., as high-performance communication solutions for paralyzed persons. We propose a multi-channel microelectrode array capable of recording ECoG field potentials with high spatial resolution. The proposed array is of a 150 mm2 total recording area; it has 124 circular electrodes (100, 300 and 500 μm in diameter) situated on the edges of concentric hexagons (min. 0.8 mm interdistance) and a skull-facing reference electrode (2.5 mm2 surface area). The array is processed as a free-standing device to enable monolithic integration of a rigid interposer, designed for soldering of fine-pitch SMD-connectors on a minimal assembly area. Electrochemical characterization revealed distinct impedance spectral bands for the 100, 300 and 500 μm-type electrodes, and for the array's own reference. Epidural recordings from the primary visual cortex (V1) of an awake Rhesus macaque showed natural electrophysiological signals and clear responses to standard visual stimulation. The ECoG electrodes of larger surface area recorded signals with greater spectral power in the gamma band, while the skull-facing reference electrode provided higher average gamma power spectral density (γPSD) than the common average referencing technique. PMID:25569757

Tectonics and crustal structure of the Saurashtra peninsula: based on Gravity and Magnetic data

NASA Astrophysics Data System (ADS)

Mishra, A. K.; Singh, A.; Singh, U. K.

2016-12-01

The Saurashtra peninsula is located at the North Western margin of the Indian shield which occurs as a horst block between the rifts namely as Kachchh, Cambay and Narmada. It is important because of occurrence of moderate earthquake and presence of mesozoic sediments below the Deccan trap. The maps of bouguer gravity anomaly and the total intensity magnetic anomalies of Saurashtra have delineated six circular gravity highs of magnitudes 40-60 mGal and 800-1000 nT respectively. In order to understand the location, structure and depth of the source body, methods like continuous wavelet transform (CWT), Euler deconvolution and power spectrum analysis have been implemented in the potential field data. The CWT and Euler deconvolution give 16-18 km average depth of volcanic plug in Junagadh and Rajula region. From the power spectrum analysis, it is found that average Moho depth in the Saurashtra is about 36-38 km. Keeping the constraints obtained from geophysical studies like borehole, deep seismic survey, receiver function analysis and geological information, combined gravity and magnetic modeling have been performed. Detailed crustal structure of the Saurashtra region has been delineated along two profiles which pass from prominent geological features Junagadh and Rajula volcanic plugs respectively.

Generating Electricity by Harnessing Air That Flows Around a Skyscraper by Using Bernoulli's Principle And The Venturi Effect w/Special Emphasis on Biomimicry

NASA Astrophysics Data System (ADS)

Pizzolato, R.

2017-12-01

Can skyscrapers become carbon neutral using wind that flows around them to power wind turbines? I say YES! To test this idea, I constructed a venturi to capture wind flowing around a skyscraper by applying Bernoulli's Principle and the Venturi Effect to power vertical axis wind turbines (VAWT) to generate electricity. The model was constructed from polycarbonate. Turbine blades (45°&60°) carved from balsa wood with square edges, airfoils, and trailing edge tubercles (Humpback whales-biomimicry) were tested in a wind tunnel. Output was measured using Vernier's Logger Pro 3.12 software, energy and wind sensors. Voltage (mV), current (mA), power (mW) and total energy (mJ) produced at winds speeds of 3.9, 5, 7.5 and 10 m/s were recorded. 10 trials were performed for each blade angle and each blade design for a total of 240 trials. Trials were 100 seconds long and recorded at a rate of 10 measurements/second. The blades that showed the largest %Δ in total average energy output (mJ) were the 60° airfoil blades w/ tubercles on the trailing edge (20,490 mJ) when compared to 60° square edged blades (7,021 mJ). The trend of the data showed that the airfoils w/tubercles (45° & 60°) outperformed all the other blade designs at wind speeds of 7.5 m/s and 10 m/s. Also, the 45° airfoil w/tubercles produced the highest output of 25,136 mJ! This was possibly due to the improved aerodynamics of the tubercle blades which led to improvements in lift and a reduction in drag. The data shows that turbine blades that incorporate biomimicry in their design result in more efficient power output. Through biomimicry, it is possible to efficiently generate electricity with a skyscraper and reduce our dependence upon fossil fuels!

Nitrogen oxide emission calculation for post-Panamax container ships by using engine operation power probability as weighting factor: A slow-steaming case.

PubMed

Cheng, Chih-Wen; Hua, Jian; Hwang, Daw-Shang

2018-06-01

In this study, the nitrogen oxide (NO x ) emission factors and total NO x emissions of two groups of post-Panamax container ships operating on a long-term slow-steaming basis along Euro-Asian routes were calculated using both the probability density function of engine power levels and the NO x emission function. The main engines of the five sister ships in Group I satisfied the Tier I emission limit stipulated in MARPOL (International Convention for the Prevention of Pollution from Ships) Annex VI, and those in Group II satisfied the Tier II limit. The calculated NO x emission factors of the Group I and Group II ships were 14.73 and 17.85 g/kWhr, respectively. The total NO x emissions of the Group II ships were determined to be 4.4% greater than those of the Group I ships. When the Tier II certification value was used to calculate the average total NO x emissions of Group II engines, the result was lower than the actual value by 21.9%. Although fuel consumption and carbon dioxide (CO 2 ) emissions were increased by 1.76% because of slow steaming, the NO x emissions were markedly reduced by 17.2%. The proposed method is more effective and accurate than the NO x Technical Code 2008. Furthermore, it can be more appropriately applied to determine the NO x emissions of international shipping inventory. The usage of operating power probability density function of diesel engines as the weighting factor and the NO x emission function obtained from test bed for calculating NO x emissions is more accurate and practical. The proposed method is suitable for all types and purposes of diesel engines, irrespective of their operating power level. The method can be used to effectively determine the NO x emissions of international shipping and inventory applications and should be considered in determining the carbon tax to be imposed in the future.

Environmental effects of interstate power trading on electricity consumption mixes.

PubMed

Marriott, Joe; Matthews, H Scott

2005-11-15

Although many studies of electricity generation use national or state average generation mix assumptions, in reality a great deal of electricity is transferred between states with very different mixes of fossil and renewable fuels, and using the average numbers could result in incorrect conclusions in these studies. We create electricity consumption profiles for each state and for key industry sectors in the U.S. based on existing state generation profiles, net state power imports, industry presence by state, and an optimization model to estimate interstate electricity trading. Using these "consumption mixes" can provide a more accurate assessment of electricity use in life-cycle analyses. We conclude that the published generation mixes for states that import power are misleading, since the power consumed in-state has a different makeup than the power that was generated. And, while most industry sectors have consumption mixes similar to the U.S. average, some of the most critical sectors of the economy--such as resource extraction and material processing sectors--are very different. This result does validate the average mix assumption made in many environmental assessments, but it is important to accurately quantify the generation methods for electricity used when doing life-cycle analyses.

Naive vs. Sophisticated Methods of Forecasting Public Library Circulations.

ERIC Educational Resources Information Center

Brooks, Terrence A.

1984-01-01

Two sophisticated--autoregressive integrated moving average (ARIMA), straight-line regression--and two naive--simple average, monthly average--forecasting techniques were used to forecast monthly circulation totals of 34 public libraries. Comparisons of forecasts and actual totals revealed that ARIMA and monthly average methods had smallest mean…

Ozone monitoring instrument observations of interannual increases in SO2 emissions from Indian coal-fired power plants during 2005-2012.

PubMed

Lu, Zifeng; Streets, David G; de Foy, Benjamin; Krotkov, Nickolay A

2013-12-17

Due to the rapid growth of electricity demand and the absence of regulations, sulfur dioxide (SO2) emissions from coal-fired power plants in India have increased notably in the past decade. In this study, we present the first interannual comparison of SO2 emissions and the satellite SO2 observations from the Ozone Monitoring Instrument (OMI) for Indian coal-fired power plants during the OMI era of 2005-2012. A detailed unit-based inventory is developed for the Indian coal-fired power sector, and results show that its SO2 emissions increased dramatically by 71% during 2005-2012. Using the oversampling technique, yearly high-resolution OMI maps for the whole domain of India are created, and they reveal a continuous increase in SO2 columns over India. Power plant regions with annual SO2 emissions greater than 50 Gg year(-1) produce statistically significant OMI signals, and a high correlation (R = 0.93) is found between SO2 emissions and OMI-observed SO2 burdens. Contrary to the decreasing trend of national mean SO2 concentrations reported by the Indian Government, both the total OMI-observed SO2 and annual average SO2 concentrations in coal-fired power plant regions increased by >60% during 2005-2012, implying the air quality monitoring network needs to be optimized to reflect the true SO2 situation in India.

The Relieving Effects of BrainPower Advanced, a Dietary Supplement, in Older Adults with Subjective Memory Complaints: A Randomized, Double-Blind, Placebo-Controlled Trial.

PubMed

Zhu, Jingfen; Shi, Rong; Chen, Su; Dai, Lihua; Shen, Tian; Feng, Yi; Gu, Pingping; Shariff, Mina; Nguyen, Tuong; Ye, Yeats; Rao, Jianyu; Xing, Guoqiang

2016-01-01

Subjective memory complaints (SMCs) are common in older adults that can often predict further cognitive impairment. No proven effective agents are available for SMCs. The effect of BrainPower Advanced, a dietary supplement consisting of herbal extracts, nutrients, and vitamins, was evaluated in 98 volunteers with SMCs, averaging 67 years of age (47-88), in a randomized, double-blind, placebo-controlled trial. Subjective hypomnesis/memory loss (SML) and attention/concentration deficits (SAD) were evaluated before and after 12-week supplementation of BrainPower Advanced capsules (n = 47) or placebo (n = 51), using a 5-point memory questionnaire (1 = no/slight, 5 = severe). Objective memory function was evaluated using 3 subtests of visual/audio memory, abstraction, and memory recall that gave a combined total score. The BrainPower Advanced group had more cases of severe SML (severity ⩾ 3) (44/47) and severe SAD (43/47) than the placebo group (39/51 and 37/51, < 0.05, < 0.05, resp.) before the treatment. BrainPower Advanced intervention, however, improved a greater proportion of the severe SML (29.5%)(13/44) (P < 0.01) and SAD (34.9%)(15/43)(P < 0.01) than placebo (5.1% (2/39) and 13.5% (5/37), resp.). Thus, 3-month BrainPower Advanced supplementation appears to be beneficial to older adults with SMCs.

Power reduction by power gating in differential pair type spin-transfer-torque magnetic random access memories for low-power nonvolatile cache memories

NASA Astrophysics Data System (ADS)

Ohsawa, Takashi; Ikeda, Shoji; Hanyu, Takahiro; Ohno, Hideo; Endoh, Tetsuo

2014-01-01

Array operation currents in spin-transfer-torque magnetic random access memories (STT-MRAMs) that use four differential pair type magnetic tunnel junction (MTJ)-based memory cells (4T2MTJ, two 6T2MTJs and 8T2MTJ) are simulated and compared with that in SRAM. With L3 cache applications in mind, it is assumed that the memories are composed of 32 Mbyte capacity to be accessed in 64 byte in parallel. All the STT-MRAMs except for the 8T2MTJ one are designed with 32 bit fine-grained power gating scheme applied to eliminate static currents in the memory cells that are not accessed. The 8T2MTJ STT-MRAM, the cell’s design concept being not suitable for the fine-grained power gating, loads and saves 32 Mbyte data in 64 Mbyte unit per 1 Mbit sub-array in 2 × 103 cycles. It is shown that the array operation current of the 4T2MTJ STT-MRAM is 70 mA averaged in 15 ns write cycles at Vdd = 0.9 V. This is the smallest among the STT-MRAMs, about the half of the low standby power (LSTP) SRAM whose array operation current is totally dominated by the cells’ subthreshold leakage.

Grid regulation services for energy storage devices based on grid frequency

DOEpatents

Pratt, Richard M; Hammerstrom, Donald J; Kintner-Meyer, Michael C.W.; Tuffner, Francis K

2013-07-02

Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

Grid regulation services for energy storage devices based on grid frequency

DOEpatents

Pratt, Richard M.; Hammerstrom, Donald J.; Kintner-Meyer, Michael C. W.; Tuffner, Francis K.

2017-09-05

Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

Grid regulation services for energy storage devices based on grid frequency

DOEpatents

Pratt, Richard M; Hammerstrom, Donald J; Kintner-Meyer, Michael C.W.; Tuffner, Francis K

2014-04-15

Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

Point-ahead limitation on reciprocity tracking. [in earth-space optical link

NASA Technical Reports Server (NTRS)

Shapiro, J. H.

1975-01-01

The average power received at a spacecraft from a reciprocity-tracking transmitter is shown to be the free-space diffraction-limited result times a gain-reduction factor that is due to the point-ahead requirement. For a constant-power transmitter, the gain-reduction factor is approximately equal to the appropriate spherical-wave mutual-coherence function. For a constant-average-power transmitter, an exact expression is obtained for the gain-reduction factor.

47 CFR 15.403 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... or below its maximum level. (p) Pulse. A pulse is a continuous transmission of a sequence of... bridge in a peer-to-peer connection or as a connector between the wired and wireless segments of the... the presence of a radar. (c) Average Symbol Envelope Power. The average symbol envelope power is the...

Nonimaging concentrators for diode-pumped slab lasers

NASA Astrophysics Data System (ADS)

Lacovara, Philip; Gleckman, Philip L.; Holman, Robert L.; Winston, Roland

1991-10-01

Diode-pumped slab lasers require concentrators for high-average power operation. We detail the properties of diode lasers and slab lasers which set the concentration requirements and the concentrator design methodologies that are used, and describe some concentrator designs used in high-average power slab lasers at Lincoln Laboratory.

Energy production estimation for Kosh-Agach grid-tie photovoltaic power plant for different photovoltaic module types

NASA Astrophysics Data System (ADS)

Gabderakhmanova, T. S.; Kiseleva, S. V.; Frid, S. E.; Tarasenko, A. B.

2016-11-01

This paper is devoted to calculation of yearly energy production, demanded area and capital costs for first Russian 5 MW grid-tie photovoltaic (PV) plant in Altay Republic that is named Kosh-Agach. Simple linear calculation model, involving average solar radiation and temperature data, grid-tie inverter power-efficiency dependence and PV modules parameters is proposed. Monthly and yearly energy production, equipment costs and demanded area for PV plant are estimated for mono-, polycrystalline and amorphous modules. Calculation includes three types of initial radiation and temperature data—average day for every month from NASA SSE, average radiation and temperature for each day of the year from NASA POWER and typical meteorology year generated from average data for every month. The peculiarities for each type of initial data and their influence on results are discussed.

Average BER analysis of SCM-based free-space optical systems by considering the effect of IM3 with OSSB signals under turbulence channels.

PubMed

Lim, Wansu; Cho, Tae-Sik; Yun, Changho; Kim, Kiseon

2009-11-09

In this paper, we derive the average bit error rate (BER) of subcarrier multiplexing (SCM)-based free space optics (FSO) systems using a dual-drive Mach-Zehnder modulator (DD-MZM) for optical single-sideband (OSSB) signals under atmospheric turbulence channels. In particular, we consider the third-order intermodulation (IM3), a significant performance degradation factor, in the case of high input signal power systems. The derived average BER, as a function of the input signal power and the scintillation index, is employed to determine the optimum number of SCM users upon the designing FSO systems. For instance, when the user number doubles, the input signal power decreases by almost 2 dBm under the log-normal and exponential turbulence channels at a given average BER.

[Vein morphology after endovenous laser coagulation at different power and similar linear density of energy].

PubMed

Fokin, A A; Borsuk, D A; Kazachkov, E L; Gorelik, G L; Bagaev, K V

The purpose of the study was to assess the depth of damage to the venous wall after endovenous laser coagulation (EVLC) at different power of the unit - 5, 7 and 10 W and similar linear density of energy (LDE) - approximately 70 J/cm. Our prospective comparative morphological study with blinding included a total of 30 patients subjected to EVLC of the great saphenous vein using the unit with a wavelength of 1,470 nm and radial light guides with automatic traction. The patients were divided into three groups, each comprising 10 patients. The unit's power (W) during EVLC and velocity of light guide traction (mm/s) in group one amounted to 5 and 0.7 (LDE - 71.4 J/cm), in group two to 7 and 1.0 (LDE - 70 J/cm) and in group tree to 10 and 1.5 (LDE - 66.7 J/cm), respectively. The coagulated veins were then procured from mini approaches and subjected to three sections made at a distance of 2 mm from each other. Specimens were stained with haematoxylin-eosin and picrofuxin according to the van Gieson technique. Then, in four places of each section (at 3, 6, 9 and 12 hours) we assessed the depth of the damage to the venous wall and calculated the average percentage of alteration - the ratio of the depth of the lesion to the venous wall thickness. The average depth of damage to the venous wall (μm) amounted in the first group to 122.9 ?m, in the second group to 182.9 μm, and in the third group to 267 μmm. The index of alteration (%) averagely amounted: in group one to 25.7, in group two to 37.9 and in group three (at a power of 10 W) to 55.5 (p=0.0001 when comparing each of the groups (the Kruskal-Wallis test)). Hence, despite an inconsiderable decrease of the LDE from the first to the third group, as power increased, the depth and percentage of damage to venous walls increased statistically significantly. It follows from the above-mentioned that: 1) an increase in power (from 5 to 10 W) of the unit during EVLC at comparable LDE (approximately 70 J/cm) leads to a deeper damage of the venous wall; 2) it is necessary to carry out a clinical study aimed at comparing different modes of coagulation, with the assessment of the frequency of recanalization and the level of pain syndrome.

Fiber-based tunable repetition rate source for deep tissue two-photon fluorescence microscopy

PubMed Central

Charan, Kriti; Li, Bo; Wang, Mengran; Lin, Charles P.; Xu, Chris

2018-01-01

Deep tissue multiphoton imaging requires high peak power to enhance signal and low average power to prevent thermal damage. Both goals can be advantageously achieved through laser repetition rate tuning instead of simply adjusting the average power. We show that the ideal repetition rate for deep two-photon imaging in the mouse brain is between 1 and 10 MHz, and we present a fiber-based source with an arbitrarily tunable repetition rate within this range. The performance of the new source is compared to a mode-locked Ti:Sapphire (Ti:S) laser for in vivo imaging of mouse brain vasculature. At 2.5 MHz, the fiber source requires 5.1 times less average power to obtain the same signal as a standard Ti:S laser operating at 80 MHz. PMID:29760989

Modeling nexus of urban heat island mitigation strategies with electricity/power usage and consumer costs: a case study for Phoenix, Arizona, USA

NASA Astrophysics Data System (ADS)

Silva, Humberto; Fillpot, Baron S.

2018-01-01

A reduction in both power and electricity usage was determined using a previously validated zero-dimensional energy balance model that implements mitigation strategies used to reduce the urban heat island (UHI) effect. The established model has been applied to show the change in urban characteristic temperature when executing four common mitigation strategies: increasing the overall (1) emissivity, (2) vegetated area, (3) thermal conductivity, and (4) albedo of the urban environment in a series of increases by 5, 10, 15, and 20% from baseline values. Separately, a correlation analysis was performed involving meteorological data and total daily energy (TDE) consumption where the 24-h average temperature was shown to have the greatest correlation to electricity service data in the Phoenix, Arizona, USA, metropolitan region. A methodology was then developed for using the model to predict TDE consumption reduction and corresponding cost-saving analysis when implementing the four mitigation strategies. The four modeled UHI mitigation strategies, taken in combination, would lead to the largest percent reduction in annual energy usage, where increasing the thermal conductivity is the single most effective mitigation strategy. The single least effective mitigation strategy, increasing the emissivity by 5% from the baseline value, resulted in an average calculated reduction of about 1570 GWh in yearly energy usage with a corresponding 157 million dollar cost savings. When the four parameters were increased in unison by 20% from baseline values, an average calculated reduction of about 2050 GWh in yearly energy usage was predicted with a corresponding 205 million dollar cost savings.

Metabolic power demands of rugby league match play.

PubMed

Kempton, Tom; Sirotic, Anita Claire; Rampinini, Ermanno; Coutts, Aaron James

2015-01-01

To describe the metabolic demands of rugby league match play for positional groups and compare match distances obtained from high-speed-running classifications with those derived from high metabolic power. Global positioning system (GPS) data were collected from 25 players from a team competing in the National Rugby League competition over 39 matches. Players were classified into positional groups (adjustables, outside backs, hit-up forwards, and wide-running forwards). The GPS devices provided instantaneous raw velocity data at 5 Hz, which were exported to a customized spreadsheet. The spreadsheet provided calculations for speed-based distances (eg, total distance; high-speed running, >14.4 km/h; and very-high-speed running, >18.1 km/h) and metabolic-power variables (eg, energy expenditure; average metabolic power; and high-power distance, >20 W/kg). The data show that speed-based distances and metabolic power varied between positional groups, although this was largely related to differences in time spent on field. The distance covered at high running speed was lower than that obtained from high-power thresholds for all positional groups; however, the difference between the 2 methods was greatest for hit-up forwards and adjustables. Positional differences existed for all metabolic parameters, although these are at least partially related to time spent on the field. Higher-speed running may underestimate the demands of match play when compared with high-power distance-although the degree of difference between the measures varied by position. The analysis of metabolic power may complement traditional speed-based classifications and improve our understanding of the demands of rugby league match play.

Machine Learning Based Multi-Physical-Model Blending for Enhancing Renewable Energy Forecast -- Improvement via Situation Dependent Error Correction

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

Lu, Siyuan; Hwang, Youngdeok; Khabibrakhmanov, Ildar

With increasing penetration of solar and wind energy to the total energy supply mix, the pressing need for accurate energy forecasting has become well-recognized. Here we report the development of a machine-learning based model blending approach for statistically combining multiple meteorological models for improving the accuracy of solar/wind power forecast. Importantly, we demonstrate that in addition to parameters to be predicted (such as solar irradiance and power), including additional atmospheric state parameters which collectively define weather situations as machine learning input provides further enhanced accuracy for the blended result. Functional analysis of variance shows that the error of individual modelmore » has substantial dependence on the weather situation. The machine-learning approach effectively reduces such situation dependent error thus produces more accurate results compared to conventional multi-model ensemble approaches based on simplistic equally or unequally weighted model averaging. Validation over an extended period of time results show over 30% improvement in solar irradiance/power forecast accuracy compared to forecasts based on the best individual model.« less

In-situ thermal annealing of on-membrane silicon-on-insulator semiconductor-based devices after high gamma dose irradiation.

PubMed

Amor, S; André, N; Kilchytska, V; Tounsi, F; Mezghani, B; Gérard, P; Ali, Z; Udrea, F; Flandre, D; Francis, L A

2017-05-05

In this paper, we investigate the recovery of some semiconductor-based components, such as N/P-type field-effect transistors (FETs) and a complementary metal-oxide-semiconductor (CMOS) inverter, after being exposed to a high total dose of gamma ray radiation. The employed method consists mainly of a rapid, low power and in situ annealing mitigation technique by silicon-on-insulator micro-hotplates. Due to the ionizing effect of the gamma irradiation, the threshold voltages showed an average shift of -580 mV for N-channel transistors, and -360 mV for P-MOSFETs. A 4 min double-cycle annealing of components with a heater temperature up to 465 °C, corresponding to a maximum power of 38 mW, ensured partial recovery but was not sufficient for full recovery. The degradation was completely recovered after the use of a built-in high temperature annealing process, up to 975 °C for 8 min corresponding to a maximum power of 112 mW, which restored the normal operating characteristics for all devices after their irradiation.

Ultrasonic Power Output Measurement by Pulsed Radiation Pressure

PubMed Central

Fick, Steven E.; Breckenridge, Franklin R.

1996-01-01

Direct measurements of time-averaged spatially integrated output power radiated into reflectionless water loads can be made with high accuracy using techniques which exploit the radiation pressure exerted by sound on all objects in its path. With an absorptive target arranged to intercept the entirety of an ultrasound beam, total beam power can be determined as accurately as the radiation force induced on the target can be measured in isolation from confounding forces due to buoyancy, streaming, surface tension, and vibration. Pulse modulation of the incident ultrasound at a frequency well above those characteristics of confounding phenomena provides the desired isolation and other significant advantages in the operation of the radiation force balance (RFB) constructed in 1974. Equipped with purpose-built transducers and electronics, the RFB is adjusted to equate the radiation force and a counterforce generated by an actuator calibrated against reference masses using direct current as the transfer variable. Improvements made during its one overhaul in 1988 have nearly halved its overall measurement uncertainty and extended the capabilities of the RFB to include measuring the output of ultrasonic systems with arbitrary pulse waveforms. PMID:27805084

In-situ thermal annealing of on-membrane silicon-on-insulator semiconductor-based devices after high gamma dose irradiation

NASA Astrophysics Data System (ADS)

Amor, S.; André, N.; Kilchytska, V.; Tounsi, F.; Mezghani, B.; Gérard, P.; Ali, Z.; Udrea, F.; Flandre, D.; Francis, L. A.

2017-05-01

In this paper, we investigate the recovery of some semiconductor-based components, such as N/P-type field-effect transistors (FETs) and a complementary metal-oxide-semiconductor (CMOS) inverter, after being exposed to a high total dose of gamma ray radiation. The employed method consists mainly of a rapid, low power and in situ annealing mitigation technique by silicon-on-insulator micro-hotplates. Due to the ionizing effect of the gamma irradiation, the threshold voltages showed an average shift of -580 mV for N-channel transistors, and -360 mV for P-MOSFETs. A 4 min double-cycle annealing of components with a heater temperature up to 465 °C, corresponding to a maximum power of 38 mW, ensured partial recovery but was not sufficient for full recovery. The degradation was completely recovered after the use of a built-in high temperature annealing process, up to 975 °C for 8 min corresponding to a maximum power of 112 mW, which restored the normal operating characteristics for all devices after their irradiation.

Application of the SAROTA index in real-life scenario

NASA Astrophysics Data System (ADS)

Rojatkar, A.; Monebhurrun, V.

2014-10-01

A unique parameter referred to as the SAROTA index which accounts for both the specific absorption rate (SAR) and the over-the-air (OTA) performance of a mobile phone was previously proposed to characterize the real-life exposure. The applicability of the SAROTA index was confirmed using SAR and total radiated power (TRP) data obtained under laboratory conditions wherein the power control (PC) enforced on the mobile phone was implemented artificially. Herein the investigation is extended to measurements conducted for the speech mode of operation in real-life scenarios. Based on the actual PC implemented during the communication with the base station, the instantaneous and average real-life exposure experienced by the mobile phone user is analyzed and compared to the predicted SAROTA index. To capture the PC in real-time, a set of hardware modified phones with embedded network monitoring software are used. The instantaneous uplink transmit power level (TX_LEV) along with various downlink parameters such as the receive signal level (RX_LEV) and received signal quality (RX_QUAL) of the communication link are thus available for performing a comprehensive RF exposure analysis.

HISCAT: A proposed new scatter facility in Northern Scandinavia

NASA Technical Reports Server (NTRS)

Bostrom, R.; Thide, B.

1986-01-01

It is proposed that a new versatile ionospheric and atmospheric scatter radar be constructed in northern Scandavia through a multinational collaborative effort. The new facility tentatively named HISCAT (High frequency, High power, High latitude, Heating and Ionospheric Scatter facility), should be used for scientific investigations of: the physics of the neutral (middle) atmosphere; fundamental plasma phenomena, natural or artificially induced in the ionosphere; electrodynamic conditions at high altitudes above the auroral region and in the polar cap ionosphere; plasma waves in the solar atmosphere. The system should thus be able to operate as a mesosphere-stratosphere-troposphere (MST) radar, a so-called ionospheric modification facility, incoherent-scatter radar, coherent-scatter radar, and solar radar. Basically, the new facility should be a device that can operate simultaneously on several frequencies in the frequency range 5 to 50 MHz not covered by other instruments. It should comprise: powerful transmitters, capable of delivering a total average power of several megawatts; an advanced phased antenna array of high gain forming one or two steerable and well collimated beams; and an advanced data collection and analysis system.

High-power picosecond laser with 400W average power for large scale applications

NASA Astrophysics Data System (ADS)

Du, Keming; Brüning, Stephan; Gillner, Arnold

2012-03-01

Laser processing is generally known for low thermal influence, precise energy processing and the possibility to ablate every type of material independent on hardness and vaporisation temperature. The use of ultra-short pulsed lasers offers new possibilities in the manufacturing of high end products with extra high processing qualities. For achieving a sufficient and economical processing speed, high average power is needed. To scale the power for industrial uses the picosecond laser system has been developed, which consists of a seeder, a preamplifier and an end amplifier. With the oscillator/amplifier system more than 400W average power and maximum pulse energy 1mJ was obtained. For study of high speed processing of large embossing metal roller two different ps laser systems have been integrated into a cylinder engraving machine. One of the ps lasers has an average power of 80W while the other has 300W. With this high power ps laser fluencies of up to 30 J/cm2 at pulse repetition rates in the multi MHz range have been achieved. Different materials (Cu, Ni, Al, steel) have been explored for parameters like ablation rate per pulse, ablation geometry, surface roughness, influence of pulse overlap and number of loops. An enhanced ablation quality and an effective ablation rate of 4mm3/min have been achieved by using different scanning systems and an optimized processing strategy. The max. achieved volume rate is 20mm3/min.

Continuous-wave and quasi-continuous wave thulium-doped all-fiber laser: implementation on kidney stone fragmentations.

PubMed

Pal, Debasis; Ghosh, Aditi; Sen, Ranjan; Pal, Atasi

2016-08-10

A continuous-wave (CW) as well as quasi-continuous wave (QCW) thulium-doped all-fiber laser at 1.94 μm has been designed for targeting applications in urology. The thulium-doped active fiber with an octagonal-shaped inner cladding is pumped at 793 nm to achieve stable CW laser power of 10 W with 32% lasing efficiency (against launched pump power). The linear variation of laser power with pump offers a scope of further power scaling. A QCW operation with variation of duty cycle from 0.5% to 90%, repetition rate from 0.1 Hz to 1 kHz, and pulse width from 40 μs to 2 s has been presented. Laser power of 9.5 W in CW mode of operation and average power of 5.2 W with energy range of 10.4-104 mJ in QCW mode of operation has been employed to fragment calcium oxalate monohydrate kidney stones (size of 1.5-4 cm) having different colors and composition. Dependence of ablation threshold, ablation rate, and average fragmented particle size on the average power and energy has been studied. One minute of laser exposure results in fragmentation of a stone surface with ablation rate of 8  mg/min having minimum particle size of 6.54 μm with an average size of 20-100 μm ensuring the natural removal of fragmented parts through the urethra.

Ruthenium Oxide Electrochemical Super Capacitor Optimization for Pulse Power Applications

NASA Technical Reports Server (NTRS)

Merryman, Stephen A.; Chen, Zheng

2000-01-01

Electrical actuator systems are being pursued as alternatives to hydraulic systems to reduce maintenance time, weight and costs while increasing reliability. Additionally, safety and environmental hazards associated with the hydraulic fluids can be eliminated. For most actuation systems, the actuation process is typically pulsed with high peak power requirements but with relatively modest average power levels. The power-time requirements for electrical actuators are characteristic of pulsed power technologies where the source can be sized for the average power levels while providing the capability to achieve the peak requirements. Among the options for the power source are battery systems, capacitor systems or battery-capacitor hybrid systems. Battery technologies are energy dense but deficient in power density; capacitor technologies are power dense but limited by energy density. The battery-capacitor hybrid system uses the battery to supply the average power and the capacitor to meet the peak demands. It has been demonstrated in previous work that the hybrid electrical power source can potentially provide a weight savings of approximately 59% over a battery-only source. Electrochemical capacitors have many properties that make them well-suited for electrical actuator applications. They have the highest demonstrated energy density for capacitive storage (up to 100 J/g), have power densities much greater than most battery technologies (greater than 30kW/kg), are capable of greater than one million charge-discharge cycles, can be charged at extremely high rates, and have non-explosive failure modes. Thus, electrochemical capacitors exhibit a combination of desirable battery and capacitor characteristics.

Radially polarized passively mode-locked thin-disk laser oscillator emitting sub-picosecond pulses with an average output power exceeding the 100 W level.

PubMed

Beirow, Frieder; Eckerle, Michael; Dannecker, Benjamin; Dietrich, Tom; Ahmed, Marwan Abdou; Graf, Thomas

2018-02-19

We report on a high-power passively mode-locked radially polarized Yb:YAG thin-disk oscillator providing 125 W of average output power. To the best of our knowledge, this is the highest average power ever reported from a mode-locked radially polarized oscillator without subsequent amplification stages. Mode-locking was achieved by implementing a SESAM as the cavity end mirror and the radial polarization of the LG* 01 mode was obtained by means of a circular Grating Waveguide Output Coupler. The repetition rate was 78 MHz. A pulse duration of 0.97 ps and a spectral bandwidth of 1.4 nm (FWHM) were measured at the maximum output power. This corresponds to a pulse energy of 1.6 µJ and a pulse peak power of 1.45 MW. A high degree of radial polarization of 97.3 ± 1% and an M 2 -value of 2.16 which is close to the theoretical value for the LG* 01 doughnut mode were measured.

Diamond Raman laser emitting at 1194, 1419, and 597 nm

NASA Astrophysics Data System (ADS)

Pashinin, V. P.; Ralchenko, V. G.; Bolshakov, A. P.; Ashkinazi, E. E.; Konov, V. I.

2018-03-01

A Raman laser based on a synthetic diamond crystal pumped by nanosecond pulses of a 1030-nm Yb : YAG laser and emitting in the IR region at the first and second Stokes wavelengths of 1194 and 1419 nm, respectively, was developed. The conversion efficiency was 34% with a slope efficiency of 50% and an average power of 1.1 W at a wavelength of 1194 nm; the average power at 1419 nm was 0.52 W. Frequency doubling of the first Stokes component in a nonlinear BBO crystal resulted in orange (597.3 nm) radiation with a pulse energy of 0.15 mJ, an average power of 0.22 W, and a maximum efficiency of 20%.

Calculating High Speed Centrifugal Compressor Performance from Averaged Measurements

NASA Astrophysics Data System (ADS)

Lou, Fangyuan; Fleming, Ryan; Key, Nicole L.

2012-12-01

To improve the understanding of high performance centrifugal compressors found in modern aircraft engines, the aerodynamics through these machines must be experimentally studied. To accurately capture the complex flow phenomena through these devices, research facilities that can accurately simulate these flows are necessary. One such facility has been recently developed, and it is used in this paper to explore the effects of averaging total pressure and total temperature measurements to calculate compressor performance. Different averaging techniques (including area averaging, mass averaging, and work averaging) have been applied to the data. Results show that there is a negligible difference in both the calculated total pressure ratio and efficiency for the different techniques employed. However, the uncertainty in the performance parameters calculated with the different averaging techniques is significantly different, with area averaging providing the least uncertainty.

Microwave Ablation: Comparison of Simultaneous and Sequential Activation of Multiple Antennas in Liver Model Systems.

PubMed

Harari, Colin M; Magagna, Michelle; Bedoya, Mariajose; Lee, Fred T; Lubner, Meghan G; Hinshaw, J Louis; Ziemlewicz, Timothy; Brace, Christopher L

2016-01-01

To compare microwave ablation zones created by using sequential or simultaneous power delivery in ex vivo and in vivo liver tissue. All procedures were approved by the institutional animal care and use committee. Microwave ablations were performed in both ex vivo and in vivo liver models with a 2.45-GHz system capable of powering up to three antennas simultaneously. Two- and three-antenna arrays were evaluated in each model. Sequential and simultaneous ablations were created by delivering power (50 W ex vivo, 65 W in vivo) for 5 minutes per antenna (10 and 15 minutes total ablation time for sequential ablations, 5 minutes for simultaneous ablations). Thirty-two ablations were performed in ex vivo bovine livers (eight per group) and 28 in the livers of eight swine in vivo (seven per group). Ablation zone size and circularity metrics were determined from ablations excised postmortem. Mixed effects modeling was used to evaluate the influence of power delivery, number of antennas, and tissue type. On average, ablations created by using the simultaneous power delivery technique were larger than those with the sequential technique (P < .05). Simultaneous ablations were also more circular than sequential ablations (P = .0001). Larger and more circular ablations were achieved with three antennas compared with two antennas (P < .05). Ablations were generally smaller in vivo compared with ex vivo. The use of multiple antennas and simultaneous power delivery creates larger, more confluent ablations with greater temperatures than those created with sequential power delivery. © RSNA, 2015.

High-power picosecond pulse delivery through hollow core photonic band gap fibers

NASA Astrophysics Data System (ADS)

Michieletto, Mattia; Johansen, Mette M.; Lyngsø, Jens K.; Lægsgaard, Jesper; Bang, Ole; Alkeskjold, Thomas T.

2016-03-01

We demonstrated robust and bend insensitive fiber delivery of high power laser with diffraction limited beam quality for two different kinds of hollow core band gap fibers. The light source for this experiment consists of ytterbium-doped double clad fiber aeroGAIN-ROD-PM85 in a high power amplifier setup. It provided 22ps pulses with a maximum average power of 95W, 40MHz repetition rate at 1032nm (~2.4μJ pulse energy), with M2 <1.3. We determined the facet damage threshold for a 7-cells hollow core photonic bandgap fiber and showed up to 59W average power output for a 5 meters fiber. The damage threshold for a 19-cell hollow core photonic bandgap fiber exceeded the maximum power provided by the light source and up to 76W average output power was demonstrated for a 1m fiber. In both cases, no special attention was needed to mitigate bend sensitivity. The fibers were coiled on 8 centimeters radius spools and even lower bending radii were present. In addition, stimulated rotational Raman scattering arising from nitrogen molecules was measured through a 42m long 19 cell hollow core fiber.

Environmentally Powered Yarn Arrays that Sense, Actuate, Harvest, and Store Energy (NBIT III)

DTIC Science & Technology

2016-11-15

than the gravimetric power generation capability of a cars combustion engine and (2) functioned as a torsional artificial muscle to rotate a heavy...rotor to over 90,000 rpm. By driving this torsional actuation using 19.6C fluctuations in air temperature, we obtained an average output electrical ...rpm. By driving this torsional actuation using 19.6°C fluctuations in air temperature, we obtained an average output electrical power of 124 W per

Wind Power Potential at Abandoned Mines in Korea

NASA Astrophysics Data System (ADS)

jang, M.; Choi, Y.; Park, H.; Go, W.

2013-12-01

This study performed an assessment of wind power potential at abandoned mines in the Kangwon province by analyzing gross energy production, greenhouse gas emission reduction and economic effects estimated from a 600 kW wind turbine. Wind resources maps collected from the renewable energy data center in Korea Institute of Energy Research(KIER) were used to determine the average wind speed, temperature and atmospheric pressure at hub height(50 m) for each abandoned mine. RETScreen software developed by Natural Resources Canada(NRC) was utilized for the energy, emission and financial analyses of wind power systems. Based on the results from 5 representative mining sites, we could know that the average wind speed at hub height is the most critical factor for assessing the wind power potential. Finally, 47 abandoned mines that have the average wind speed faster than 6.5 m/s were analyzed, and top 10 mines were suggested as relatively favorable sites with high wind power potential in the Kangwon province.

Rawhide Energy Station, Fort Collins, Colorado

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

Peltier, R.

2008-10-15

The staff of Platte River Power Authority's Rawhide Energy Station have been racking up operating stats and an environmental performance record that is the envy of other plant managers. In the past decade Rawhide has enjoyed an equivalent availability factor in the mid to high 90s and an average capacity factor approaching 90%. Still not content with this performance, Rawhide invested in new technology and equipment upgrades to further optimise performance, reduce emissions, and keep cost competitive. The Energy Station includes four GE France 7EA natural gas-fired turbines totalling 260 MW and a 274 MW coal-fired unit located in northeasternmore » Colorado. 7 figs.« less

Parasitic oscillation suppression in solid state lasers using absorbing thin films

DOEpatents

Zapata, L.E.

1994-08-02

A thin absorbing film is bonded onto at least certain surfaces of a solid state laser gain medium. An absorbing metal-dielectric multilayer film is optimized for a broad range of incidence angles, and is resistant to the corrosive/erosive effects of a coolant such as water, used in the forced convection cooling of the film. Parasitic oscillations hamper the operation of solid state lasers by causing the decay of stored energy to amplified rays trapped within the gain medium by total and partial internal reflections off the gain medium facets. Zigzag lasers intended for high average power operation require the ASE absorber. 16 figs.

The power of remote sensing: Global monitoring of weather, water, and crops with satellites and data integration

USGS Publications Warehouse

Senay, Gabriel

2016-01-01

Imagine a family of six whose livelihood is based on subsistence farming on a small, maybe one hectare, parcel of land somewhere in Africa. The seasonal rainfall varies greatly, from 500 to 800 mm per year, and the land is degraded. Thus, the parcel’s total productivity is not more than 1.5 tonnes in a good year, hardly meeting the family’s food requirements. The lack of surplus grain eliminates the need for grain storage structures, and due to the high rainfall variability, drought hazard is always looming, with an average recurrence interval of five to ten years.

Parasitic oscillation suppression in solid state lasers using absorbing thin films

DOEpatents

Zapata, Luis E.

1994-01-01

A thin absorbing film is bonded onto at least certain surfaces of a solid state laser gain medium. An absorbing metal-dielectric multilayer film is optimized for a broad range of incidence angles, and is resistant to the corrosive/erosive effects of a coolant such as water, used in the forced convection cooling of the film. Parasitic oscillations hamper the operation of solid state lasers by causing the decay of stored energy to amplified rays trapped within the gain medium by total and partial internal reflections off the gain medium facets. Zigzag lasers intended for high average power operation require the ASE absorber.

76 FR 65616 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Central Air...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-24

... measure the energy efficiency, energy use or estimated annual operating cost of a covered product over an... the June 2010 NOPR would be used to determine the average power consumption of a residential central... residential central air conditioners, the unit's average power consumption during the heating season...

Estimation of absorbed radiation dose rates in wild rodents inhabiting a site severely contaminated by the Fukushima Dai-ichi nuclear power plant accident.

PubMed

Kubota, Yoshihisa; Takahashi, Hiroyuki; Watanabe, Yoshito; Fuma, Shoichi; Kawaguchi, Isao; Aoki, Masanari; Kubota, Masahide; Furuhata, Yoshiaki; Shigemura, Yusaku; Yamada, Fumio; Ishikawa, Takahiro; Obara, Satoshi; Yoshida, Satoshi

2015-04-01

The dose rates of radiation absorbed by wild rodents inhabiting a site severely contaminated by the Fukushima Dai-ichi Nuclear Power Plant accident were estimated. The large Japanese field mouse (Apodemus speciosus), also called the wood mouse, was the major rodent species captured in the sampling area, although other species of rodents, such as small field mice (Apodemus argenteus) and Japanese grass voles (Microtus montebelli), were also collected. The external exposure of rodents calculated from the activity concentrations of radiocesium ((134)Cs and (137)Cs) in litter and soil samples using the ERICA (Environmental Risk from Ionizing Contaminants: Assessment and Management) tool under the assumption that radionuclides existed as the infinite plane isotropic source was almost the same as those measured directly with glass dosimeters embedded in rodent abdomens. Our findings suggest that the ERICA tool is useful for estimating external dose rates to small animals inhabiting forest floors; however, the estimated dose rates showed large standard deviations. This could be an indication of the inhomogeneous distribution of radionuclides in the sampled litter and soil. There was a 50-fold difference between minimum and maximum whole-body activity concentrations measured in rodents at the time of capture. The radionuclides retained in rodents after capture decreased exponentially over time. Regression equations indicated that the biological half-life of radiocesium after capture was 3.31 d. At the time of capture, the lowest activity concentration was measured in the lung and was approximately half of the highest concentration measured in the mixture of muscle and bone. The average internal absorbed dose rate was markedly smaller than the average external dose rate (<10% of the total absorbed dose rate). The average total absorbed dose rate to wild rodents inhabiting the sampling area was estimated to be approximately 52 μGy h(-1) (1.2 mGy d(-1)), even 3 years after the accident. This dose rate exceeds 0.1-1 mGy d(-1) derived consideration reference level for Reference rat proposed by the International Commission on Radiological Protection (ICRP). Copyright © 2015 Elsevier Ltd. All rights reserved.

OMI air-quality monitoring over the Middle East

NASA Astrophysics Data System (ADS)

Barkley, Michael P.; González Abad, Gonzalo; Kurosu, Thomas P.; Spurr, Robert; Torbatian, Sara; Lerot, Christophe

2017-04-01

Using Ozone Monitoring Instrument (OMI) trace gas vertical column observations of nitrogen dioxide (NO2), formaldehyde (HCHO), sulfur dioxide (SO2), and glyoxal (CHOCHO), we have conducted a robust and detailed time series analysis to assess changes in local air quality for over 1000 locations (focussing on urban, oil refinery, oil port, and power plant targets) over the Middle East for 2005-2014. Apart from NO2, which is highest over urban locations, average tropospheric column levels of these trace gases are highest over oil ports and refineries. The highest average pollution levels over urban settlements are typically in Bahrain, Kuwait, Qatar, and the United Arab Emirates. We detect 278 statistically significant and real linear NO2 trends in total. Over urban areas NO2 increased by up to 12 % yr-1, with only two locations showing a decreasing trend. Over oil refineries, oil ports, and power plants, NO2 increased by about 2-9 % yr-1. For HCHO, 70 significant and real trends were detected, with HCHO increasing by 2-7 % yr-1 over urban settlements and power plants and by about 2-4 % yr-1 over refineries and oil ports. Very few SO2 trends were detected, which varied in direction and magnitude (23 increasing and 9 decreasing). Apart from two locations where CHOCHO is decreasing, we find that glyoxal tropospheric column levels are not changing over the Middle East. Hence, for many locations in the Middle East, OMI observes a degradation in air quality over 2005-2014. This study therefore demonstrates the capability of OMI to generate long-term air-quality monitoring at local scales over this region.

Power Management for Space Advanced Life Support

NASA Technical Reports Server (NTRS)

Jones, Harry

2001-01-01

Space power systems include the power source, storage, and management subsystems. In current crewed spacecraft, solar cells are the power source, batteries provide storage, and the crew performs any required load scheduling. For future crewed planetary surface systems using Advanced Life Support, we assume that plants will be grown to produce much of the crew's food and that nuclear power will be employed. Battery storage is much more costly than nuclear power capacity and so is not likely to be used. We investigate the scheduling of power demands by the crew or automatic control, to reduce the peak power load and the required generating capacity. The peak to average power ratio is a good measure of power use efficiency. We can easily schedule power demands to reduce the peak power from its maximum, but simple scheduling approaches may not find the lowest possible peak to average power ratio. An initial power scheduling example was simple enough for a human to solve, but a more complex example with many intermittent load demands required automatic scheduling. Excess power is a free resource and can be used even for minor benefits.

Design and fabrication of vibration based energy harvester using microelectromechanical system piezoelectric cantilever for low power applications.

PubMed

Kim, Moonkeun; Lee, Sang-Kyun; Yang, Yil Suk; Jeong, Jaehwa; Min, Nam Ki; Kwon, Kwang-Ho

2013-12-01

We fabricated dual-beam cantilevers on the microelectromechanical system (MEMS) scale with an integrated Si proof mass. A Pb(Zr,Ti)O3 (PZT) cantilever was designed as a mechanical vibration energy-harvesting system for low power applications. The resonant frequency of the multilayer composition cantilevers were simulated using the finite element method (FEM) with parametric analysis carried out in the design process. According to simulations, the resonant frequency, voltage, and average power of a dual-beam cantilever was 69.1 Hz, 113.9 mV, and 0.303 microW, respectively, at optimal resistance and 0.5 g (gravitational acceleration, m/s2). Based on these data, we subsequently fabricated cantilever devices using dual-beam cantilevers. The harvested power density of the dual-beam cantilever compared favorably with the simulation. Experiments revealed the resonant frequency, voltage, and average power density to be 78.7 Hz, 118.5 mV, and 0.34 microW, respectively. The error between the measured and simulated results was about 10%. The maximum average power and power density of the fabricated dual-beam cantilever at 1 g were 0.803 microW and 1322.80 microW cm(-3), respectively. Furthermore, the possibility of a MEMS-scale power source for energy conversion experiments was also tested.

Jupiter's Auroral Energy Input Observed by Hisaki/EXCEED and its Modulations by Io's Volcanic Activity

NASA Astrophysics Data System (ADS)

Tao, C.; Kimura, T.; Tsuchiya, F.; Murakami, G.; Yoshioka, K.; Kita, H.; Yamazaki, A.; Kasaba, Y.; Yoshikawa, I.; Fujimoto, M.

2016-12-01

Aurora is an important indicator representing the momentum transfer from the fast-rotating outer planet to the magnetosphere and the energy input into the atmosphere through the magnetosphere-ionosphere coupling. Long-term monitoring of Jupiter's northern aurora was achieved by the Extreme Ultraviolet (EUV) spectrometer called EXCEED (Extreme Ultraviolet Spectroscope for Exospheric Dynamics) onboard JAXA's Earth-orbiting planetary space telescope Hisaki until today after its launch in September 2013. We have proceeded the statistical survey of the Jupiter's auroral energy input into the upper atmosphere. The auroral electron energy is estimated using a hydrocarbon color ratio (CR) adopted for the wavelength range of EXCEED, and the emission power in the long wavelength range 138.5-144.8 nm is used as an indicator of total emitted power before hydrocarbon absorption and auroral electron energy flux. Temporal dynamic variation of the auroral intensity was detected when Io's volcanic activity and thus EUV emission from the Io plasma torus are enhanced in the early 2015. Average of the total input power over 80 days increases by 10% with sometimes sporadically more than a factor of 3 upto 7, while the CR indicates the auroral electron energy decrease by 20% during the volcanic event compared to the other period. This indicates much more increase in the current system and Joule heating which contributes heating of the upper atmosphere. We will discuss the impact of this event on the upper atmosphere and ionosphere.

Evaluation of the Environmental Bias on Accelerometer-Measured Total Daily Activity Counts and Owner Survey Responses in Dogs with Osteoarthritis.

PubMed

Katz, Erin M; Scott, Ruth M; Thomson, Christopher B; Mesa, Eileen; Evans, Richard; Conzemius, Michael G

2017-11-01

Objective  To determine if environmental variables affect the average daily activity counts (AC) of dogs with osteoarthritis (OA) and/or owners' perception of their dog's clinical signs or quality of life. Methods  The AC and Canine Brief Pain Inventory (CBPI) owner questionnaires of 62 dogs with OA were compared with daily environmental variables including the following: average temperature (°C), high temperature (°C), low temperature (°C), relative humidity (%), total precipitation (mm), average barometric pressure (hPa) and total daylight hours. Results  Daily AC significantly correlated with average temperature and total daylight hours, but average temperature and total daylight hours accounted for less than 1% of variation in AC. No other significant relationships were found between daily AC and daily high temperature, low temperature, relative humidity, total precipitation or average barometric pressure. No statistical relationship was found between daily AC and the CBPI, nor between environmental variables and the CBPI. Canine Brief Pain Inventory scores for pain severity and pain interference decreased significantly over the test period. Clinical Significance  The relationship between daily AC and average temperature and total daylight hours was significant, but unlikely to be clinically significant. Thus, environmental variables do not appear to have a clinically relevant bias on AC or owner CBPI questionnaires. The decrease over time in CBPI pain severity and pain interference values suggests owners completing the CBPI in this study were influenced by a caregiver placebo effect. Schattauer GmbH Stuttgart.

High-power highly stable passively Q-switched fiber laser based on monolayer graphene

NASA Astrophysics Data System (ADS)

Wu, Hanshuo; Song, Jiaxin; Wu, Jian; Xu, Jiangming; Xiao, Hu; Leng, Jinyong; Zhou, Pu

2018-03-01

We demonstrate a monolayer graphene-based passively Q-switched fiber laser with three-stage amplifiers that can deliver an average power of over 80 W at 1064 nm. The highest average power achieved is 84.1 W, with a pulse energy of 1.67 mJ. To the best of our knowledge this is the first report of a high-power passively Q-switched fiber laser in the 1 µm range. More importantly, the Q-switched fiber laser operated stably during a week of tests for a few hours per day, which proves the stability and practical application potential of graphene in high-power pulsed fiber lasers.

Analysis of data from Viking RPA's

NASA Technical Reports Server (NTRS)

Hanson, W. B.

1981-01-01

Measurements of the martian ionosphere performed by Viking Retarding Potential Analyzer (RPA) are reported. Viking RPA measurements of low energy electron fluxes out to 16,000 km above the Mars surface are discussed including both energy spectra and periods of continuous monitoring of the total flux above 15 ev. The mean electron current at energies greater than ev increases montonically by nearly two orders of magnitude from about 9000 km down to 700 km, but no clear signature of the bow shock is seen. The total wave power in the 2 sec measurement intervals for this current does, however, show a broad peak near 1700 km altitude. These variations in the low energy electron fluxes are related to whistler mode oscillations in the solar wind plasma. It is concluded that there may be a highly turbulent shock structure that masks a clear signature of the bow shock in the time averaged data.

Predictions of Supersonic Jet Mixing and Shock-Associated Noise Compared With Measured Far-Field Data

NASA Technical Reports Server (NTRS)

Dahl, Milo D.

2010-01-01

Codes for predicting supersonic jet mixing and broadband shock-associated noise were assessed using a database containing noise measurements of a jet issuing from a convergent nozzle. Two types of codes were used to make predictions. Fast running codes containing empirical models were used to compute both the mixing noise component and the shock-associated noise component of the jet noise spectrum. One Reynolds-averaged, Navier-Stokes-based code was used to compute only the shock-associated noise. To enable the comparisons of the predicted component spectra with data, the measured total jet noise spectra were separated into mixing noise and shock-associated noise components. Comparisons were made for 1/3-octave spectra and some power spectral densities using data from jets operating at 24 conditions covering essentially 6 fully expanded Mach numbers with 4 total temperature ratios.

Performance analysis of fiber-based free-space optical communications with coherent detection spatial diversity.

PubMed

Li, Kangning; Ma, Jing; Tan, Liying; Yu, Siyuan; Zhai, Chao

2016-06-10

The performances of fiber-based free-space optical (FSO) communications over gamma-gamma distributed turbulence are studied for multiple aperture receiver systems. The equal gain combining (EGC) technique is considered as a practical scheme to mitigate the atmospheric turbulence. Bit error rate (BER) performances for binary-phase-shift-keying-modulated coherent detection fiber-based free-space optical communications are derived and analyzed for EGC diversity receptions through an approximation method. To show the net diversity gain of a multiple aperture receiver system, BER performances of EGC are compared with a single monolithic aperture receiver system with the same total aperture area (same average total incident optical power on the aperture surface) for fiber-based free-space optical communications. The analytical results are verified by Monte Carlo simulations. System performances are also compared for EGC diversity coherent FSO communications with or without considering fiber-coupling efficiencies.

Thermal effects in high average power optical parametric amplifiers.

PubMed

Rothhardt, Jan; Demmler, Stefan; Hädrich, Steffen; Peschel, Thomas; Limpert, Jens; Tünnermann, Andreas

2013-03-01

Optical parametric amplifiers (OPAs) have the reputation of being average power scalable due to the instantaneous nature of the parametric process (zero quantum defect). This Letter reveals serious challenges originating from thermal load in the nonlinear crystal caused by absorption. We investigate these thermal effects in high average power OPAs based on beta barium borate. Absorption of both pump and idler waves is identified to contribute significantly to heating of the nonlinear crystal. A temperature increase of up to 148 K with respect to the environment is observed and mechanical tensile stress up to 40 MPa is found, indicating a high risk of crystal fracture under such conditions. By restricting the idler to a wavelength range far from absorption bands and removing the crystal coating we reduce the peak temperature and the resulting temperature gradient significantly. Guidelines for further power scaling of OPAs and other nonlinear devices are given.

Test techniques for model development of repetitive service energy storage capacitors

NASA Astrophysics Data System (ADS)

Thompson, M. C.; Mauldin, G. H.

1984-03-01

The performance of the Sandia perfluorocarbon family of energy storage capacitors was evaluated. The capacitors have a much lower charge noise signature creating new instrumentation performance goals. Thermal response to power loading and the importance of average and spot heating in the bulk regions require technical advancements in real time temperature measurements. Reduction and interpretation of thermal data are crucial to the accurate development of an intelligent thermal transport model. The thermal model is of prime interest in the high repetition rate, high average power applications of power conditioning capacitors. The accurate identification of device parasitic parameters has ramifications in both the average power loss mechanisms and peak current delivery. Methods to determine the parasitic characteristics and their nonlinearities and terminal effects are considered. Meaningful interpretations for model development, performance history, facility development, instrumentation, plans for the future, and present data are discussed.

Capacity of MIMO free space optical communications using multiple partially coherent beams propagation through non-Kolmogorov strong turbulence.

PubMed

Deng, Peng; Kavehrad, Mohsen; Liu, Zhiwen; Zhou, Zhou; Yuan, Xiuhua

2013-07-01

We study the average capacity performance for multiple-input multiple-output (MIMO) free-space optical (FSO) communication systems using multiple partially coherent beams propagating through non-Kolmogorov strong turbulence, assuming equal gain combining diversity configuration and the sum of multiple gamma-gamma random variables for multiple independent partially coherent beams. The closed-form expressions of scintillation and average capacity are derived and then used to analyze the dependence on the number of independent diversity branches, power law α, refractive-index structure parameter, propagation distance and spatial coherence length of source beams. Obtained results show that, the average capacity increases more significantly with the increase in the rank of MIMO channel matrix compared with the diversity order. The effect of the diversity order on the average capacity is independent of the power law, turbulence strength parameter and spatial coherence length, whereas these effects on average capacity are gradually mitigated as the diversity order increases. The average capacity increases and saturates with the decreasing spatial coherence length, at rates depending on the diversity order, power law and turbulence strength. There exist optimal values of the spatial coherence length and diversity configuration for maximizing the average capacity of MIMO FSO links over a variety of atmospheric turbulence conditions.

Environmental effects of interstate power trading on electricity consumption mixes

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

Joe Marriott; H. Scott Matthews

2005-11-15

Although many studies of electricity generation use national or state average generation mix assumptions, in reality a great deal of electricity is transferred between states with very different mixes of fossil and renewable fuels, and using the average numbers could result in incorrect conclusions in these studies. The authors create electricity consumption profiles for each state and for key industry sectors in the U.S. based on existing state generation profiles, net state power imports, industry presence by state, and an optimization model to estimate interstate electricity trading. Using these 'consumption mixes' can provide a more accurate assessment of electricity usemore » in life-cycle analyses. It is concluded that the published generation mixes for states that import power are misleading, since the power consumed in-state has a different makeup than the power that was generated. And, while most industry sectors have consumption mixes similar to the U.S. average, some of the most critical sectors of the economy - such as resource extraction and material processing sectors - are very different. This result does validate the average mix assumption made in many environmental assessments, but it is important to accurately quantify the generation methods for electricity used when doing life-cycle analyses. 16 refs., 7 figs., 2 tabs.« less

Estimating the snow water equivalent on a glacierized high elevation site (Forni Glacier, Italy)

NASA Astrophysics Data System (ADS)

Senese, Antonella; Maugeri, Maurizio; Meraldi, Eraldo; Verza, Gian Pietro; Azzoni, Roberto Sergio; Compostella, Chiara; Diolaiuti, Guglielmina

2018-04-01

We present and compare 11 years of snow data (snow depth and snow water equivalent, SWE) measured by an automatic weather station (AWS) and corroborated by data from field campaigns on the Forni Glacier in Italy. The aim of the analysis is to estimate the SWE of new snowfall and the annual SWE peak based on the average density of the new snow at the site (corresponding to the snowfall during the standard observation period of 24 h) and automated snow depth measurements. The results indicate that the daily SR50 sonic ranger measurements and the available snow pit data can be used to estimate the mean new snow density value at the site, with an error of ±6 kg m-3. Once the new snow density is known, the sonic ranger makes it possible to derive SWE values with an RMSE of 45 mm water equivalent (if compared with snow pillow measurements), which turns out to be about 8 % of the total SWE yearly average. Therefore, the methodology we present is interesting for remote locations such as glaciers or high alpine regions, as it makes it possible to estimate the total SWE using a relatively inexpensive, low-power, low-maintenance, and reliable instrument such as the sonic ranger.

Mechanical vs. informational components of price impact

NASA Astrophysics Data System (ADS)

Doyne Farmer, J.; Zamani, N.

2007-01-01

We study the problem of what causes prices to change. It is well known that trading impacts prices — orders to buy drive the price up, and orders to sell drive it down. We introduce a means of decomposing the total impact of trading into two components, defining the mechanical impact of a trading order as the change in future prices in the absence of any future changes in decision making, and the informational impact as the remainder of the total impact once mechanical impact is removed. This decomposition is performed using order book data from the London Stock Exchange. The average mechanical impact of a market order decays to zero as a function of time, at an asymptotic rate that is consistent with a power law with an exponent of roughly 1.7. In contrast the average informational impact builds to approach a constant value. Initially the impact is entirely mechanical, and is about half as big as the asymptotic informational impact. The size of the informational impact is positively correlated to mechanical impact. For cases where the mechanical impact is zero for all times, we find that the informational impact is negative, i.e. buy market orders that have no mechanical impact at all generate strong negative price responses.

Study of the effect of electromagnetic fields on indoor and outdoor radon concentrations

NASA Astrophysics Data System (ADS)

Haider, Lina M.; Shareef, N. R.; Darwoysh, H. H.; Mansour, H. L.

2018-05-01

In the present work, the effect of electromagnetic fields produced by high voltage power lines(132kV) and indoor equipments on the indoor and outdoor average radon concentrations in Al-Kazaliya and Hay Al-Adil regions in Baghdad city were studied using CR-39 track detectors and a gauss-meter.Results of measurements of the present study, have shown that the highest value for the indoor average radon concentration (76.56± 8.44 Bq / m3) was recorded for sample A1(Hay Al-Adel) at a distance of (20 m) from the high voltage power lines, while the lowest value for the indoor average radon concentration (30.46 ± 8.44 Bq / m3) was recorded for sample A3 (Hay Al-Adil) at a distance of (50 m) from the high voltage power lines. The indoor gaussmeter measurements were found to be ranged from (30.2 mG) to (38.5 mG). The higest value for outdoor average radon concentration and the highest gaussmeter measurements were found for sample (1), with values (92.63 ±11.2 Bq / m3) and (87.24 ± 2.85 mG), directly under the high voltage power lines respectively, while the lowest outdoor average radon concentration and the lowest gaussmeter measurements were found in sample (4),with values (34.19 ± 6.33 Bq / m3) and (1.16 ± 0.14 Bq / m3),), at a distance of (120 m) from the high voltage power lines respectively. The results of the present work have shown that there might be an influence of the electromagnetic field on radon concentrations in areas which were close to high voltage power lines and houses which have used many electric equipment for a long period of time.

High-power ultra-broadband frequency comb from ultraviolet to infrared by high-power fiber amplifiers.

PubMed

Yang, Kangwen; Li, Wenxue; Yan, Ming; Shen, Xuling; Zhao, Jian; Zeng, Heping

2012-06-04

A high-power ultra-broadband frequency comb covering the spectral range from ultraviolet to infrared was generated directly by nonlinear frequency conversion of a multi-stage high-power fiber comb amplifier. The 1030-nm infrared spectral fraction of a broadband Ti:sapphire femtosecond frequency comb was power-scaled up to 100 W average power by using a large-mode-area fiber chirped-pulse amplifier. We obtained a frequency-doubled green comb at 515 nm and frequency-quadrupled ultraviolet pulses at 258 nm with the average power of 12.8 and 1.62 W under the input infrared power of 42.2 W, respectively. The carrier envelope phase stabilization was accomplished with an ultra-narrow line-width of 1.86 mHz and a quite low accumulated phase jitter of 0.41 rad, corresponding to a timing jitter of 143 as.

Magnetically operated beam dump for dumping high power beams in a neutral beamline

DOEpatents

Dagenhart, W.K.

1984-01-27

It is an object of this invention to provide a beam dump system for a neutral beam generator which lowers the time-averaged power density of the beam dump impingement surface. Another object of this invention is to provide a beam dump system for a neutral particle beam based on reionization and subsequent magnetic beam position modulation of the beam onto a beam dump surface to lower the time-averaged power density of the beam dump ion impingement surface.

The JLab high power ERL light source

NASA Astrophysics Data System (ADS)

Neil, G. R.; Behre, C.; Benson, S. V.; Bevins, M.; Biallas, G.; Boyce, J.; Coleman, J.; Dillon-Townes, L. A.; Douglas, D.; Dylla, H. F.; Evans, R.; Grippo, A.; Gruber, D.; Gubeli, J.; Hardy, D.; Hernandez-Garcia, C.; Jordan, K.; Kelley, M. J.; Merminga, L.; Mammosser, J.; Moore, W.; Nishimori, N.; Pozdeyev, E.; Preble, J.; Rimmer, R.; Shinn, M.; Siggins, T.; Tennant, C.; Walker, R.; Williams, G. P.; Zhang, S.

2006-02-01

A new THz/IR/UV photon source at Jefferson Lab is the first of a new generation of light sources based on an Energy-Recovered, (superconducting) Linac (ERL). The machine has a 160 MeV electron beam and an average current of 10 mA in 75 MHz repetition rate hundred femtosecond bunches. These electron bunches pass through a magnetic chicane and therefore emit synchrotron radiation. For wavelengths longer than the electron bunch the electrons radiate coherently a broadband THz ˜ half cycle pulse whose average brightness is >5 orders of magnitude higher than synchrotron IR sources. Previous measurements showed 20 W of average power extracted [Carr, et al., Nature 420 (2002) 153]. The new facility offers simultaneous synchrotron light from the visible through the FIR along with broadband THz production of 100 fs pulses with >200 W of average power. The FELs also provide record-breaking laser power [Neil, et al., Phys. Rev. Lett. 84 (2000) 662]: up to 10 kW of average power in the IR from 1 to 14 μm in 400 fs pulses at up to 74.85 MHz repetition rates and soon will produce similar pulses of 300-1000 nm light at up to 3 kW of average power from the UV FEL. These ultrashort pulses are ideal for maximizing the interaction with material surfaces. The optical beams are Gaussian with nearly perfect beam quality. See www.jlab.org/FEL for details of the operating characteristics; a wide variety of pulse train configurations are feasible from 10 ms long at high repetition rates to continuous operation. The THz and IR system has been commissioned. The UV system is to follow in 2005. The light is transported to user laboratories for basic and applied research. Additional lasers synchronized to the FEL are also available. Past activities have included production of carbon nanotubes, studies of vibrational relaxation of interstitial hydrogen in silicon, pulsed laser deposition and ablation, nitriding of metals, and energy flow in proteins. This paper will present the status of the system and discuss some of the discoveries we have made concerning the physics performance, design optimization, and operational limitations of such a first generation high power ERL light source.

Kinetic and kinematic differences between squats performed with and without elastic bands.

PubMed

Israetel, Michael A; McBride, Jeffrey M; Nuzzo, James L; Skinner, Jared W; Dayne, Andrea M

2010-01-01

The purpose of this investigation was to compare kinetic and kinematic variables between squats performed with and without elastic bands equalized for total work. Ten recreationally weight trained males completed 1 set of 5 squats without (Wht) and with (Band) elastic bands as resistance. Squats were completed while standing on a force platform with bar displacement measured using 2 potentiometers. Electromyography (EMG) was obtained from the vastus lateralis. Average force-time, velocity-time, power-time, and EMG-time graphs were generated and statistically analyzed for mean differences in values between the 2 conditions during the eccentric and concentric phases. The Band condition resulted in significantly higher forces in comparison to the Wht condition during the first 25% of the eccentric phase and the last 10% of the concentric phase (p < or = 0.05). However, the Wht condition resulted in significantly higher forces during the last 5% of the eccentric phase and the first 5% of the concentric phase in comparison to the Band condition. The Band condition resulted in significantly higher power and velocity values during the first portion of the eccentric phase and the latter portion of the concentric phase. Vastus lateralis muscle activity during the Band condition was significantly greater during the first portion of the eccentric phase and latter portion of the concentric phase as well. This investigation indicates that squats equalized for total work with and without elastic bands significantly alter the force-time, power-time, velocity-time, and EMG-time curves associated with the movements. Specifically, elastic bands seem to increase force, power, and muscle activity during the early portions of the eccentric phase and latter portions of the concentric phase.

Laser technologies for ultrasensitive groundwater dating using long-lived isotopes

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

Backus, Sterling

In this phase I work, we propose to construct and demonstrate a 103 nm laser based on resonantly enhanced and phase matched fifth harmonic generation in hollow waveguides driven by a high power, low cost and compact ultrafast fiber laser. (Figure 4) This VUV laser source can potentially produce >100 milliwatts of VUV light at 103 nm with pulse repetition-rates of 100 kHz to 100 MHz, ideal for the above-mentioned applications. This technology is state-of-the-art and potentially compact, fieldable, low-cost, and of broad interest for a variety of science and technology applications. Laser-based VUV sources in the past have exhibitedmore » low repetition rate, low efficiency, low beam quality, and are based on expensive laser sources. Our approch is to combine ultrafast fiber laser drive technology, ultrafast pulses, and our proven waveguide technology, to create a high repetition rate, high average power VUV source for producing high yield metastable Krypton. At KMLabs we have been offering EUV light sources employing the high harmonic generation (HHG) process driven by high-power femtosecond lasers for >5 years now. Recently, we have developed much smaller scale (briefcase size), but still high average power femtosecond fiber laser sources to supply other markets, and create new ones. By combining these new laser sources with our patented waveguide frequency upconversion technology, we expect to be able to obtain >20mW average power initially, with potentially much higher powers depending on wavelength, in an affordable VUV product. For comparison, our current EUV light sources based on ti:sapphire generate an average power of ~5 µW (albeit at shorter 29 nm wavelength), and we are aware of one other supplier that has developed a VUV (112 nm) light source with ~10-20 µW power.« less

Intelligent Hybrid Vehicle Power Control - Part 1: Machine Learning of Optimal Vehicle Power

DTIC Science & Technology

2012-06-30

time window ),[ tWt DT : vave, vmax, vmin, ac, vst and vend, where the first four parameters are, respectively, the average speed, maximum speed...minimum speed and average acceleration, during the time period ),[ tWt DT , vst is the vehicle speed at )( DTWt  , and vend is the vehicle

Performance of a 14.9-kW laminated-frame dc series motor with chopper controller

NASA Technical Reports Server (NTRS)

Schwab, J. R.

1979-01-01

Traction motor using two types of excitation: ripple free dc from a motor generator set for baseline data and chopped dc as supplied by a battery and chopper controller was tested. For the same average values of input voltage and current, the power output was independent of the type of excitation. At the same speeds, motor efficiency at low power output (corresponding to low duty cycle of the controller) was 5 to 10 percentage points less on chopped dc than on ripple-free dc. This illustrates that for chopped waveforms, it is incorrect to calculate input power as the product of average voltage and average current. Locked-rotor torque, no load losses, and magnetic saturation data were so determined.

PQScal (Power Quality Score Calculation for Distribution Systems with DER Integration)

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

Power Quality is of great importance to evaluate the “health” of a distribution system, especially when the distributed energy resource (DER) penetration becomes more significant. The individual components that make up power quality, such as voltage magnitude and unbalance, can be measured in simulations or in the field, however, a comprehensive method to incorporate all of these values into a single score doesn't exist. As a result, we propose a methodology to quantify the power quality health using the single number value, named as Power Quality Score (PQS). The PQS is dependent on six metrics that are developed based onmore » both components that directly impact power quality and those are often reference in the context of power quality. These six metrics are named as System Average Voltage Magnitude Violation Index (SAVMVI), System Average Voltage Fluctuation Index (SAVFI), System Average Voltage Unbalance Index (SAVUI), System Control Device Operation Index (SCDOI), System Reactive Power Demand Index (SRPDI) and System Energy Loss Index (SELI). This software tool, PQScal, is developed based on this novel PQS methodology. Besides of traditional distribution systems, PQScal can also measure the power quality for distribution systems with various DER penetrations. PQScal has been tested on two utility distribution feeders with distinct model characteristics and its effectiveness has been proved. In sum, PQScal can help utilities or other parties to measure the power quality of distribution systems with DER integration easily and effectively.« less

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

Larsen, Peter H.; LaCommare, Kristina H.; Eto, Joseph H.

Here, this study examines the relationship between annual changes in electricity reliability reported by a large cross-section of U.S. electricity distribution utilities over a period of 13 years and a broad set of potential explanatory variables, including weather and utility characteristics. We find statistically significant correlations between the average number of power interruptions experienced annually and above average wind speeds, precipitation, lightning strikes, and a measure of population density: customers per line mile. We also find significant relationships between the average number of minutes of power interruptions experienced and above average wind speeds, precipitation, cooling degree-days, and one strategy usedmore » to mitigate the impacts of severe weather: the amount of underground transmission and distribution line miles. Perhaps most importantly, we find a significant time trend of increasing annual average number of minutes of power interruptions over time—especially when interruptions associated with extreme weather are included. Lastly, the research method described in this analysis can provide a basis for future efforts to project long-term trends in reliability and the associated benefits of strategies to improve grid resiliency to severe weather—both in the U.S. and abroad.« less

Microgrid optimal scheduling considering impact of high penetration wind generation

NASA Astrophysics Data System (ADS)

Alanazi, Abdulaziz

The objective of this thesis is to study the impact of high penetration wind energy in economic and reliable operation of microgrids. Wind power is variable, i.e., constantly changing, and nondispatchable, i.e., cannot be controlled by the microgrid controller. Thus an accurate forecasting of wind power is an essential task in order to study its impacts in microgrid operation. Two commonly used forecasting methods including Autoregressive Integrated Moving Average (ARIMA) and Artificial Neural Network (ANN) have been used in this thesis to improve the wind power forecasting. The forecasting error is calculated using a Mean Absolute Percentage Error (MAPE) and is improved using the ANN. The wind forecast is further used in the microgrid optimal scheduling problem. The microgrid optimal scheduling is performed by developing a viable model for security-constrained unit commitment (SCUC) based on mixed-integer linear programing (MILP) method. The proposed SCUC is solved for various wind penetration levels and the relationship between the total cost and the wind power penetration is found. In order to reduce microgrid power transfer fluctuations, an additional constraint is proposed and added to the SCUC formulation. The new constraint would control the time-based fluctuations. The impact of the constraint on microgrid SCUC results is tested and validated with numerical analysis. Finally, the applicability of proposed models is demonstrated through numerical simulations.

In vivo demonstration of ultrasound power delivery to charge implanted medical devices via acute and survival porcine studies

PubMed Central

Radziemski, Leon; Makin, Inder Raj S.

2015-01-01

Animal studies are an important step in proving the utility and safety of an ultrasound based implanted battery recharging system. To this end an Ultrasound Electrical Recharging System (USER™) was developed and tested. Experiments in vitro demonstrated power deliveries at the battery of up to 600 mW through 10 – 15 mm of tissue, 50 mW of power available at tissue depths of up to 50 mm, and the feasibility of using transducers bonded to titanium as used in medical implants. Acute in vivo studies in a porcine model were used to test reliability of power delivery, temperature excursions, and cooling techniques. The culminating five-week survival study involved repeated battery charging, a total of 10.5 hours of ultrasound exposure of the intervening living tissue, with an average RF input to electrical charging efficiency of 20%. This study was potentially the first long term cumulative living-tissue exposure using transcutaneous ultrasound power transmission to an implanted receiver in situ. Histology of the exposed tissue showed changes attributable primarily due to surgical implantation of the prototype device, and no damage due to the ultrasound exposure. The in vivo results are indicative of the potential safe delivery of ultrasound energy for a defined set of source conditions for charging batteries within implants. PMID:26243566

In vivo demonstration of ultrasound power delivery to charge implanted medical devices via acute and survival porcine studies.

PubMed

Radziemski, Leon; Makin, Inder Raj S

2016-01-01

Animal studies are an important step in proving the utility and safety of an ultrasound based implanted battery recharging system. To this end an Ultrasound Electrical Recharging System (USER™) was developed and tested. Experiments in vitro demonstrated power deliveries at the battery of up to 600 mW through 10-15 mm of tissue, 50 mW of power available at tissue depths of up to 50 mm, and the feasibility of using transducers bonded to titanium as used in medical implants. Acute in vivo studies in a porcine model were used to test reliability of power delivery, temperature excursions, and cooling techniques. The culminating five-week survival study involved repeated battery charging, a total of 10.5h of ultrasound exposure of the intervening living tissue, with an average RF input to electrical charging efficiency of 20%. This study was potentially the first long term cumulative living-tissue exposure using transcutaneous ultrasound power transmission to an implanted receiver in situ. Histology of the exposed tissue showed changes attributable primarily due to surgical implantation of the prototype device, and no damage due to the ultrasound exposure. The in vivo results are indicative of the potential safe delivery of ultrasound energy for a defined set of source conditions for charging batteries within implants. Copyright © 2015 Elsevier B.V. All rights reserved.

Metabolic Power in Team Sports - Part 2: Aerobic and Anaerobic Energy Yields.

PubMed

Osgnach, Cristian; di Prampero, Pietro Enrico

2018-06-14

A previous approach to estimate the time course of instantaneous metabolic power and O 2 consumption in team sports has been updated to assess also energy expenditure against air resistance and to identify walking and running separately. Whole match energy expenditure turned out ≈14% smaller than previously obtained, the fraction against the air resistance amounting to ≈2% of the total. Estimated net O 2 consumption and overall energy expenditure are fairly close to those measured by means of a portable metabolic cart; the average difference, after a 45 min exercise period of variable intensity and mode, amounting to ≈10%. Aerobic and anaerobic energy yields, metabolic power, energy expenditure and duration of High (HI) and Low (LI) intensity bouts can also be estimated. Indeed, data on 497 soccer players during the 2014/2015 Italian "Serie A" show that the number of HI efforts decreased from the first to the last 15-min periods of the match, without substantial changes in mean metabolic power (≈22 W·kg -1 ) and duration (≈6.5 s). On the contrary, mean metabolic power of the LI decreased (5.8 to 4.8 W·kg -1 ), mainly because of a longer duration thereof, thus underscoring the need for longer recovery periods between HI. © Georg Thieme Verlag KG Stuttgart · New York.

The architecture design of a 2mW 18-bit high speed weight voltage type DAC based on dual weight resistance chain

NASA Astrophysics Data System (ADS)

Qixing, Chen; Qiyu, Luo

2013-03-01

At present, the architecture of a digital-to-analog converter (DAC) in essence is based on the weight current, and the average value of its D/A signal current increases in geometric series according to its digital signal bits increase, which is 2n-1 times of its least weight current. But for a dual weight resistance chain type DAC, by using the weight voltage manner to D/A conversion, the D/A signal current is fixed to chain current Icha; it is only 1/2n-1 order of magnitude of the average signal current value of the weight current type DAC. Its principle is: n pairs dual weight resistances form a resistance chain, which ensures the constancy of the chain current; if digital signals control the total weight resistance from the output point to the zero potential point, that could directly control the total weight voltage of the output point, so that the digital signals directly turn into a sum of the weight voltage signals; thus the following goals are realized: (1) the total current is less than 200 μA (2) the total power consumption is less than 2 mW; (3) an 18-bit conversion can be realized by adopting a multi-grade structure; (4) the chip area is one order of magnitude smaller than the subsection current-steering type DAC; (5) the error depends only on the error of the unit resistance, so it is smaller than the error of the subsection current-steering type DAC; (6) the conversion time is only one action time of switch on or off, so its speed is not lower than the present DAC.

20 CFR 617.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-04-01

.... (e) Average weekly hours means a figure obtained by dividing: (1) Total hours worked (excluding... employment. (f) Average weekly wage means one-thirteenth of the total wages paid to an individual in the... preceding the individual's appropriate week. (g) Average weekly wage in adversely affected employment means...

High power solar array switching regulation

NASA Technical Reports Server (NTRS)

Decker, D. K.; Cassinelli, J.; Valgora, M.

1981-01-01

It is pointed out that spacecraft utilization projections for the 1980s and beyond show a trend toward extended lifetimes and larger electric power systems. The need for improved power management and energy transfer arising in connection with this trend has resulted in the conduction of a Solar Array Switching Power Management study. A description is presented of initial development work performed in the study, taking into account the characteristics for three mission classes. Attention is given to the manned LEO platform (250-kW average load), the unmanned GEO platform (50-kW average load), and an ion propulsion orbit transfer vehicle (50- to 250 kW load).

Kilohertz Pulse Repetition Frequency Slab Ti:sapphire Lasers with High Average Power (10 W)

NASA Astrophysics Data System (ADS)

Wadsworth, William J.; Coutts, David W.; Webb, Colin E.

1999-11-01

High-average-power broadband 780-nm slab Ti:sapphire lasers, pumped by a kilohertz pulse repetition frequency copper vapor laser (CVL), were demonstrated. These lasers are designed for damage-free power scaling when pumped by CVL s configured for maximum output power (of order 100 W) but with poor beam quality ( M 2 300 ). A simple Brewster-angled slab laser side pumped by a CVL produced 10-W average power (1.25-mJ pulses at 8 kHz) with 4.2-ns FWHM pulse duration at an absolute efficiency of 15% (68-W pump power). Thermal lensing in the Brewster slab laser resulted in multitransverse mode output, and pump absorption was limited to 72% by the maximum doping level for commercially available Ti:sapphire (0.25%). A slab laser with a multiply folded zigzag path was therefore designed and implemented that produced high-beam-quality (TEM 00 -mode) output when operated with cryogenic cooling and provided a longer absorption path for the pump. Excessive scattering of the Ti:sapphire beam at the crystal surfaces limited the efficiency of operation for the zigzag laser, but fluorescence diagnostic techniques, gain measurement, and modeling suggest that efficient power extraction ( 15 W TEM 00 , 23% efficiency) from this laser would be possible for crystals with an optical quality surface polish.

Study on power coupling of annular vortex beam propagating through a two-Cassegrain-telescope optical system in turbulent atmosphere.

PubMed

Wu, Huiyun; Sheng, Shen; Huang, Zhisong; Zhao, Siqing; Wang, Hua; Sun, Zhenhai; Xu, Xiegu

2013-02-25

As a new attractive application of the vortex beams, power coupling of annular vortex beam propagating through a two- Cassegrain-telescope optical system in turbulent atmosphere has been investigated. A typical model of annular vortex beam propagating through a two-Cassegrain-telescope optical system is established, the general analytical expression of vortex beams with limited apertures and the analytical formulas for the average intensity distribution at the receiver plane are derived. Under the H-V 5/7 turbulence model, the average intensity distribution at the receiver plane and power coupling efficiency of the optical system are numerically calculated, and the influences of the optical topological charge, the laser wavelength, the propagation path and the receiver apertures on the power coupling efficiency are analyzed. These studies reveal that the average intensity distribution at the receiver plane presents a central dark hollow profile, which is suitable for power coupling by the Cassegrain telescope receiver. In the optical system with optimized parameters, power coupling efficiency can keep in high values with the increase of the propagation distance. Under the atmospheric turbulent conditions, great advantages of vortex beam in power coupling of the two-Cassegrain-telescope optical system are shown in comparison with beam without vortex.