WorldWideScience

Sample records for absorbed power expected

  1. Energy policy and nuclear power. Expectations of the power industry

    International Nuclear Information System (INIS)

    Harig, H.D.

    1995-01-01

    In the opinion of the power industry, using nuclear power in Germany is a responsible attitude, while opting out of nuclear power is not. Electricity utilities will build new nuclear power plants only if the structural economic and ecological advantages of nuclear power are preserved and can be exploited in Germany. The power industry will assume responsibility for new complex, capital-intensive nuclear plants only if a broad societal consensus about this policy can be reached in this country. The power industry expects that the present squandering of nuclear power resources in Germany will be stopped. The power industry is prepared to contribute to finding a speedy consensus in energy policy, which would leave open all decisions which must not be taken today, and which would not constrain the freedom of decision of coming generations. The electricity utilities remain committed proponents of nuclear power. However, what they sell to their customers is electricity, not nuclear power. (orig.) [de

  2. EU Soft Power and the Capability-Expectations Gap

    DEFF Research Database (Denmark)

    Nielsen, Kristian L.

    2013-01-01

    does little to address the weakness of the EU as a foreign policy actor. This article elaborates on the soft power concept and on the interplay between hard and soft power as seen in the EU’s foreign policy. It argues that in few of the roles the EU seeks to fulfil does soft power in itself bridge...... the gap between the expectations and the capabilities. Rather, soft power, when it is present, widens that gap even further by adding to expectations, thus leading to even greater eventual disillusionment when the EU’s hard power capabilities do not match.......The European Union has in the past ten years frequently emphasised its soft power as its primary currency in international affairs. Yet a systematic analysis of the EU’s foreign policy performance, through the prism of the classic ‘capability-expectations gap’, suggests that soft power in itself...

  3. Realistic Specific Power Expectations for Advanced Radioisotope Power Systems

    Science.gov (United States)

    Mason, Lee S.

    2006-01-01

    Radioisotope Power Systems (RPS) are being considered for a wide range of future NASA space science and exploration missions. Generally, RPS offer the advantages of high reliability, long life, and predictable power production regardless of operating environment. Previous RPS, in the form of Radioisotope Thermoelectric Generators (RTG), have been used successfully on many NASA missions including Apollo, Viking, Voyager, and Galileo. NASA is currently evaluating design options for the next generation of RPS. Of particular interest is the use of advanced, higher efficiency power conversion to replace the previous thermoelectric devices. Higher efficiency reduces the quantity of radioisotope fuel and potentially improves the RPS specific power (watts per kilogram). Power conversion options include Segmented Thermoelectric (STE), Stirling, Brayton, and Thermophotovoltaic (TPV). This paper offers an analysis of the advanced 100 watt-class RPS options and provides credible projections for specific power. Based on the analysis presented, RPS specific power values greater than 10 W/kg appear unlikely.

  4. Power Absorption by Closely Spaced Point Absorbers in Constrained Conditions

    DEFF Research Database (Denmark)

    De Backer, G.; Vantorre, M.; Beels, C.

    2010-01-01

    , representing the wave climate at Westhinder on the Belgian Continental Shelf The impact of slamming, stroke and force restrictions on the power absorption is evaluated and optimal PTO parameters are determined For multiple bodies optimal control parameters (CP) are not only dependent on the incoming waves...... are applied to two array layouts consisting of 12 buoys in a staggered grid and 21 buoys in an aligned grid Compared to DO, it was found that individually optimising the CP increased the energy absorption at Westhinder with about 16-18% for the two layouts, respectively...

  5. A Subtle Source of Power: The Effect of Having an Expectation on Anticipated Interpersonal Power

    Science.gov (United States)

    BALDWIN, AUSTIN S.; KIVINIEMI, MARC T.; SNYDER, MARK

    2009-01-01

    In 2 studies, the authors tested the hypothesis that having information about another person can be a source of power in interpersonal interactions. In Study 1, the authors randomized participants to receive an expectation about an interaction partner, and the expectation provided an informational advantage for some participants but not for others. Participants with an advantage reported higher perceptions of power than did those who had information that did not confer an advantage; however, the effect was isolated to feelings of informational power. In Study 2, the authors examined whether the effect extended to different types of power when the information did not provide an explicit advantage. In this case, participants who received a more ambiguous expectation reported more diffuse feelings of power. The authors discuss implications for understanding the dynamics of power in social interactions. PMID:19245049

  6. Considerable hazards to be expected by nuclear power

    International Nuclear Information System (INIS)

    Mueller, H.

    1980-01-01

    The author examines the military aspects of Pu production. As reactor-Pu is applicable for nuclear weapons the civil utilization of nuclear power provides plutonium concentrations apt for military use for the goverments when closing the fuel cycle by commercial fuel reprocessing. Whether the last threshold shall be trespassed shall depend on how the political intentions of the authorities cooperate with the developments in the international area. After having illustrated the effects on the most important formations of the conflict the author concludes that a radical - utopian - solution alone can grant safety: If the whole fuel cycle is internationalized and controlled by an international authority supported by power of police. In fact, it must be expected that diplomatic and institutional solutions shall have a slower development than political risks. (HSCH) [de

  7. Wind power costs expected to decrease due to technological progress

    International Nuclear Information System (INIS)

    Williams, Eric; Hittinger, Eric; Carvalho, Rexon; Williams, Ryan

    2017-01-01

    The potential for future cost reductions in wind power affects adoption and support policies. Prior analyses of cost reductions give inconsistent results. The learning rate, or fractional cost reduction per doubling of production, ranges from −3% to +33% depending on the study. This lack of consensus has, we believe, contributed to high variability in forecasts of future costs of wind power. We find that learning rate can be very sensitive to the starting and ending years of datasets and the geographical scope of the study. Based on a single factor experience curve that accounts for capacity factor gains, wind quality decline, and exogenous shifts in capital costs, we develop an improved model with reduced temporal variability. Using a global adoption model, the wind-learning rate is between 7.7% and 11%, with a preferred estimate of 9.8%. Using global scenarios for future wind deployment, this learning rate range implies that the cost of wind power will decline from 5.5 cents/kWh in 2015 to 4.1–4.5 cents/kWh in 2030, lower than a number of other forecasts. If attained, wind power may be the cheapest form of new electricity generation by 2030, suggesting that support and investment in wind should be maintained or expanded. - Highlights: • Expectations for cost reductions in wind power is important for policy. • Wind learning rates are sensitive to data time period and regional choice. • We develop improved wind cost model with much reduced variability. • New model gives global wind learning rates between 7.7%-11%.

  8. Expectations

    DEFF Research Database (Denmark)

    depend on the reader’s own experiences, individual feelings, personal associations or on conventions of reading, interpretive communities and cultural conditions? This volume brings together narrative theory, fictionality theory and speech act theory to address such questions of expectations...... and intentionality in relation to narrative and fiction....

  9. Stable high-power saturable absorber based on polymer-black-phosphorus films

    Science.gov (United States)

    Mao, Dong; Li, Mingkun; Cui, Xiaoqi; Zhang, Wending; Lu, Hua; Song, Kun; Zhao, Jianlin

    2018-01-01

    Black phosphorus (BP), a rising two-dimensional material with a layer-number-dependent direct bandgap of 0.3-1.5 eV, is very interesting for optoelectronics applications from near- to mid-infrared wavebands. In the atmosphere, few-layer BP tends to be oxidized or degenerated during interacting with lasers. Here, we fabricate few-layer BP nanosheets based on a liquid exfoliation method using N-methylpyrrolidone as the dispersion liquid. By incorporating BP nanosheets with polymers (polyvinyl alcohol or high-melting-point polyimide), two flexible filmy BP saturable absorbers are fabricated to realize passive mode locking in erbium-doped fiber lasers. The polymer-BP saturable absorber, especially the polyimide-BP saturable absorber, can prevent the oxidation or water-induced etching under high-power laser illuminations, providing a promising candidate for Q-switchers, mode lockers, and light modulators.

  10. Absorbed dose rate in air in metropolitan Tokyo before the Fukushima Daiichi Nuclear Power Plant accident.

    Science.gov (United States)

    Inoue, K; Hosoda, M; Fukushi, M; Furukawa, M; Tokonami, S

    2015-11-01

    The monitoring of absorbed dose rate in air has been carried out continually at various locations in metropolitan Tokyo after the accident of the Fukushima Daiichi Nuclear Power Plant. While the data obtained before the accident are needed to more accurately assess the effects of radionuclide contamination from the accident, detailed data for metropolitan Tokyo obtained before the accident have not been reported. A car-borne survey of the absorbed dose rate in air in metropolitan Tokyo was carried out during August to September 2003. The average absorbed dose rate in air in metropolitan Tokyo was 49±6 nGy h(-1). The absorbed dose rate in air in western Tokyo was higher compared with that in central Tokyo. Here, if the absorbed dose rate indoors in Tokyo is equivalent to that outdoors, the annual effective dose would be calculated as 0.32 mSv y(-1). © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Effect of specific absorbed power on microwave sintering of 3YSZ ceramics

    Science.gov (United States)

    Bykov, Yu V.; Egorov, S. V.; Eremeev, A. G.; Plotnikov, I. V.; Rybakov, K. I.; Sorokin, A. A.; Kholoptsev, V. V.

    2017-07-01

    Samples of 3 % yttria-stabilized zirconia (3YSZ) ceramics have been sintered to near full density with no appreciable grain growth using an ultra-rapid microwave sintering process. The sintering experiments were carried out on a 24 GHz / 6 kW gyrotron system for microwave processing of materials with automatic process control. By varying the properties of the thermal insulation surrounding the samples it was possible to vary the microwave power required for heating. The final relative density of 3YSZ ceramic samples microwave heated at a rate of 50 °C/min to a temperature of 1400 °C without isothermal hold varied from 91.6 % when the specific absorbed microwave power was 4 W/cm3 to 99.4 % when the specific absorbed microwave power was 90 W/cm3. The specific absorbed power is therefore demonstrated to be the key parameter determining the achievable density in ultra-rapid field-assisted sintering processes.

  12. Measurement of total ultrasonic power using thermal expansion and change in buoyancy of an absorbing target.

    Science.gov (United States)

    Dubey, P K; Kumar, Yudhisther; Gupta, Reeta; Jain, Anshul; Gohiya, Chandrashekhar

    2014-05-01

    The Radiation Force Balance (RFB) technique is well established and most widely used for the measurement of total ultrasonic power radiated by ultrasonic transducer. The technique is used as a primary standard for calibration of ultrasonic transducers with relatively fair uncertainty in the low power (below 1 W) regime. In this technique, uncertainty comparatively increases in the range of few watts wherein the effects such as thermal heating of the target, cavitations, and acoustic streaming dominate. In addition, error in the measurement of ultrasonic power is also caused due to movement of absorber at relatively high radiated force which occurs at high power level. In this article a new technique is proposed which does not measure the balance output during transducer energized state as done in RFB. It utilizes the change in buoyancy of the absorbing target due to local thermal heating. The linear thermal expansion of the target changes the apparent mass in water due to buoyancy change. This forms the basis for the measurement of ultrasonic power particularly in watts range. The proposed method comparatively reduces uncertainty caused by various ultrasonic effects that occur at high power such as overshoot due to momentum of target at higher radiated force. The functionality of the technique has been tested and compared with the existing internationally recommended RFB technique.

  13. Critical power for self-focusing of optical beam in absorbing media

    Science.gov (United States)

    Qi, Pengfei; Zhang, Lin; Lin, Lie; Zhang, Nan; Wang, Yan; Liu, Weiwei

    2018-04-01

    Self-focusing effects are of central importance for most nonlinear optical effects. The critical power for self-focusing is commonly investigated theoretically without considering a material’s absorption. Although this is practicable for various materials, investigating the critical power for self-focusing in media with non-negligible absorption is also necessary, because this is the situation usually met in practice. In this paper, the simple analytical expressions describing the relationships among incident power, absorption coefficient and focal position are provided by a simple physical model based on the Fermat principle. Expressions for the absorption dependent critical power are also derived; these can play important roles in experimental and applied research on self-focusing-related nonlinear optical phenomena in absorbing media. Numerical results, based on the nonlinear wave equation—and which can predict experimental results perfectly—are also presented, and agree quantitatively with the analytical results proposed in this paper.

  14. Improved high temperature solar absorbers for use in Concentrating Solar Power central receiver applications.

    Energy Technology Data Exchange (ETDEWEB)

    Stechel, Ellen Beth; Ambrosini, Andrea; Hall, Aaron Christopher; Lambert, Timothy L.; Staiger, Chad Lynn; Bencomo, Marlene

    2010-09-01

    Concentrating solar power (CSP) systems use solar absorbers to convert the heat from sunlight to electric power. Increased operating temperatures are necessary to lower the cost of solar-generated electricity by improving efficiencies and reducing thermal energy storage costs. Durable new materials are needed to cope with operating temperatures >600 C. The current coating technology (Pyromark High Temperature paint) has a solar absorptance in excess of 0.95 but a thermal emittance greater than 0.8, which results in large thermal losses at high temperatures. In addition, because solar receivers operate in air, these coatings have long term stability issues that add to the operating costs of CSP facilities. Ideal absorbers must have high solar absorptance (>0.95) and low thermal emittance (<0.05) in the IR region, be stable in air, and be low-cost and readily manufacturable. We propose to utilize solution-based synthesis techniques to prepare intrinsic absorbers for use in central receiver applications.

  15. Design and Control of the PowerTake-Off System for a Wave Energy Converter with Multiple Absorbers

    DEFF Research Database (Denmark)

    Hansen, Rico Hjerm

    on converting bi-directional motions into electricity. All PTO technologies are kept open and based on a thorough analysis and evaluation of state-of-the-art, the PTO technologies with greatest potential are identified. The state-of-the-art covers both PTOs for wave energy, but also general advances in high...... powertransmissions, which have applicability to wave energy. One of the difficulties in PTO design is performing the trade-off between contradicting PTO characteristics, e.g. controllability, efficiency and peak power capacity. A PTO system for wave energy is a classic example of a mechatronic design problem, where...... feasibility for real PTO systems still causes dispute. In this dissertation an analytical result is provided, proving that reactive control is highly beneficial at even “low” PTO efficiencies. The formulated reactive control is tested in a wave tank with 1:20 scale absorbers, validating the expected...

  16. Parametric study on a collocated PZT beam vibration absorber and power harvester

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Shyh Chin [Mechanical Engineering, Ming Chi University of Technology, New Taipei (China); Tsai, Chao Yang [Mechanical Engineering Army Academy, R.O.C., Taoyuan (China); Liao, Hsiao Hui [LNG Construction and Project Division, CPC Corp., Taipei (China)

    2016-11-15

    The parametric effects of a PZT beam that is simultaneously used as a vibration absorber and a power harvester were investigated in this study. A cantilever beam paved with PZT layers and with added tip mass has been widely used as a harvester or sometimes as a Dynamic vibration absorber (DVA). However, the beam is rarely considered a collocated device. In this study, the first step was theoretical derivation of a distributed beam covered with bimorph PZT layers. Then, the beam was attached to a 1DOF vibratory main system. Two indicators for vibration absorption and power harvesting were defined. Numerical results demonstrated that the lumped mass ratio favored both of the abilities, but that the DVA mass ratio influenced these two abilities in exactly the opposite way. The conjunction of a harvester circuit into a DVA shifted its resonance frequency up to 5 % (an extreme case of open circuit R→∞). Simultaneous power harvesting diminished the absorption capability up to 35 % for each set of mass ratios. To achieve the maximum degree of power harvesting, a corresponding load resistance that somewhat increases with the lumped mass ratio is applied. Experimental results verified the existence of the best load resistance, but the measured harvested curve was lower than the theoretical calculation because of structure damping and deviations of PZT material properties.

  17. Great expectations. Projections of nuclear power around the world

    International Nuclear Information System (INIS)

    McDonald, Alan; Rogner, Hans-Holger; Gritsevskyi, Andrii

    2009-01-01

    In its 2008 edition of Energy, Electricity and Nuclear Power Estimates for the Period to 2030, the International Atomic Energy Agency (IAEA) has again revised its projections for nuclear power upwards. Every year since 1981 the IAEA has published 2 updated projections for the world's nuclear power generating capacity, a low projection and a high projection. The low projection is a down to earth, business-as-usual projection. The high projection takes into account government and corporate announcements about longer-term plans for nuclear investments as well as potential new national policies, e.g., to combat climate change. The results for the 2008 projections are presented. In the low projection, the projected nuclear power capacity in 2030 is 473 GW(e), some 27% higher than today's 372 GW(e). In the high projection, nuclear capacity in 2030 is 748 GW(e), double today's capacity. But while projections for nuclear power's future rose, its share of the world's electricity generation today dropped from 15% in 2006 to 14% in 2007. The main reason is that while total global electricity generation rose 4.8% from 2007 to 2008, nuclear electricity actually dropped slightly. The overall message from the IAEA's 2008 edition of Energy, Electricity and Nuclear Power Estimates for the Period to 2030 is that global electricity use will grow significantly, that nuclear power will have to expand more rapidly than it has done recently in order to maintain its share, and that nuclear power can meet the challenge. (orig.)

  18. In defense of commitment: The curative power of violated expectations.

    Science.gov (United States)

    Murray, Sandra L; Lamarche, Veronica M; Gomillion, Sarah; Seery, Mark D; Kondrak, Cheryl

    2017-11-01

    A new model of commitment defense in romantic relationships is proposed. It assumes that relationships afford a central resource for affirming meaning and purpose in the world. Consequently, violating expectations about the world outside the relationship can precipitate commitment defense inside the relationship. A meta-analysis of 5 experiments, 2 follow-up correlational studies, and a longitudinal study of the transition to first parenthood supported the model. Experimentally violating conventional expectations about the world (e.g., "hard work pays off") motivated less satisfied people to defensively affirm their commitment. Similarly, when becoming a parent naturalistically violated culturally conditioned gendered expectations about the division of household labor, less satisfied new mothers and fathers defensively affirmed their commitment from pre-to-post baby. The findings suggest that violating expected associations in the world outside the relationship motivates vulnerable people to set relationship their relationship right, thereby affirming expected associations in the relationship in the face of an unexpected world. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  19. Stability analysis of the Gyroscopic Power Take-Off wave energy point absorber

    DEFF Research Database (Denmark)

    Nielsen, Søren R. K.; Zhang, Zili; Kramer, Morten Mejlhede

    2015-01-01

    The Gyroscopic Power Take-Off (GyroPTO) wave energy point absorber consists of a float rigidly connected to a lever. The operational principle is somewhat similar to that of the so-called gyroscopic hand wrist exercisers, where the rotation of the float is brought forward by the rotational particle...... motion of the waves. At first, the equations of motion of the system are derived based on analytical rigid body dynamics. Next, assuming monochromatic waves simplified equations are derived, valid under synchronisation of the ring of the gyro to the angular frequency of the excitation. Especially...

  20. Value of forestation in absorbing carbon dioxide surrounding a coal fired power plant

    Energy Technology Data Exchange (ETDEWEB)

    Dang, V.D.; Steinberg, M.

    1980-08-01

    The dispersion of carbon dioxide emitted from 1000 MW(e) coal fired power plant is investigated. Calculated ground level carbon dioxide concentrations as a function of distance from the power plant stack is validated by the results derived from sulfur dioxide dispersion measurements. Forestation is examined as a means for removal and control of atmospheric carbon dioxide at a distance of 5 to 10 km away from the power plant stack. An equilibrium and a dynamic approach are considered. For an average temperate zone forest growth rate (7.42 mg/dm/sup 2/ h), the overall reduction in forested land area required to remove the equivalent of all of the CO/sub 2/ from a 1000 MW(e) power plant would be less than 3.3% compared to removing the equivalent amount of CO/sub 2/ by planting forests remotely from the plant. If faster growing tropical plants or trees having up to 4 times the temperate plant growth rate were used, there would be a maximum savings of 15% in forested land area compared to a remote planting. This magnitude of reduction in cultivated forest area is insufficient to recommend planting forested areas adjacent to central power stations as a means of controlling CO/sub 2/ emission. Rather it is suggested to provide sufficient increased regional forested areas on a global scale for the purposes of absorbing the equivalent increase in CO/sub 2/ emission due to increased fossil fuel use.

  1. Control Strategies for a simple Point-Absorber Connected to a Hydraulic Power Take-off

    Energy Technology Data Exchange (ETDEWEB)

    Ricci, P.; Lopez, J.; Santos, M.; Villate, J.L.; Ruiz Minguela, P.; Salcedo, F. [Tecnalia-Energia Sede de Robotiker-Tecnalia, Parque Tecnologico, Edificio 202, E-48170, Zamudio (Spain); Falcao, A.F.de O. [IDMEC, Instituto Superior Tecnico, Av. Rovisco Pais, 1, 1049-001, Lisbon (Portugal)

    2009-07-01

    Among the various types of wave energy converters currently being developed, heaving point absorbers are one of the simplest and most promising concepts, possibly due to their ease of deployment and integration in larger arrays structures. A typical efficient energy conversion system for point absorbers is based on hydraulic power take-off (PTO) systems, consisting in a double-acting cylinder and two or more accumulators, reserving fluid at different pressures and linked between them by a hydraulic motor connected to an electric generator. For the purpose of control and modulation of the power output the hydraulic circuit might include a certain number of valves that can set the pressure levels within the accumulators. This paper presents a simple model of a heaving oscillating buoy, represented by a surface-piercing cylinder, extracting power by means of a hydraulic system. The hydrodynamic behaviour of the absorber is modelled through application of the linear water wave theory. Apart from the basic elements listed above, the model of the hydraulic system includes leakages and pressure losses and takes into account the compressibility of the fluid. Also possible extra accumulators are considered in order to improve the performance of the hydraulic system by means of properly controlled valves. The function of these extra accumulators consists in storing and releasing energy to the system when this is desirable for the improvement of the power output. Simulations were carried out through a time-domain approach making use of the Cummins equation and considering regular monochromatic waves and irregular wave-trains. The control of the system is managed by means of control valves whose opening will be depending on the sign of the velocity of the buoy and the pressure levels. Three possible aims were assumed for the control strategies investigated: maximisation of the average power output, stabilisation of the output (in terms of rotational velocity and/or electrical

  2. Stability analysis of the Gyroscopic Power Take-Off wave energy point absorber

    Science.gov (United States)

    Nielsen, Søren R. K.; Zhang, Zili; Kramer, Morten M.; Olsen, Jan

    2015-10-01

    The Gyroscopic Power Take-Off (GyroPTO) wave energy point absorber consists of a float rigidly connected to a lever. The operational principle is somewhat similar to that of the so-called gyroscopic hand wrist exercisers, where the rotation of the float is brought forward by the rotational particle motion of the waves. At first, the equations of motion of the system are derived based on analytical rigid body dynamics. Next, assuming monochromatic waves simplified equations are derived, valid under synchronisation of the ring of the gyro to the angular frequency of the excitation. Especially, it is demonstrated that the dynamics of the ring can be described as an autonomous nonlinear single-degree-of-freedom system, affected by three different types of point attractors. One where the ring vibrations are attracted to a static equilibrium point indicating unstable synchronisation and two types of attractors where the ring is synchronised to the wave angular frequency, either rotating in one or the opposite direction. Finally, the stability conditions and the basins of attraction to the point attractors defining the synchronised motion are determined.

  3. High-temperature stable absorber coatings for linear concentrating solar thermal power plants; Hochtemperaturstabile Absorberschichten fuer linear konzentrierende solarthermische Kraftwerke

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrandt, Christina

    2009-03-23

    This work describes the development of new absorber coatings for different applications - para-bolic trough and linear Fresnel collectors - and operating conditions - absorber in vacuum or in air. The demand for higher efficiencies of solar thermal power plants using parabolic trough technology results in higher temperatures in the collectors and on the absorber tubes. As heat losses increase strongly with increasing temperatures, the need for a lower emissivity of the absorber coating at constant absorptivity arises. The linear Fresnel application envisions ab-sorber tubes stable in air at high temperatures of about 450 C, which are to date commercially not available. This work comprises the theoretical background, the modeling and the fabrication of absorber tubes including the technology transfer to a production-size inline sputter coater. In annealing tests and accompanying optical measurements, degradation processes have been observed and specified more precisely by material characterization techniques. The simulations provided the capability of different materials used as potential IR-reflector. The highest selectivity can be achieved by applying silver which consequently has been chosen for the application in absorber coatings of the parabolic trough technology. Thin silver films how-ever need to be stabilized when used at high temperatures. Appropriate barrier layers as well as process and layer parameters were identified. A high selectivity was achieved and stability of the absorber coating for 1200 h at 500 C in vacuum has been demonstrated. For the application in air, silver was also analyzed as a potential IR-reflector. Even though the stability could be increased considerably, it nevertheless proved to be insufficient. The main factors influencing stability in a positive way are the use of higher quality polishing, additional barrier layers and adequate process parameters. This knowledge was applied for developing coatings which are stable in air at

  4. Gyroscopic power take-off wave energy point absorber in irregular sea states

    DEFF Research Database (Denmark)

    Zhang, Zili; Chen, Bei; Nielsen, Søren R.K.

    2017-01-01

    Highlights •A GyroPTO wave energy point absorber with magnetic coupling mechanism is proposed. •A 4DOF nonlinear model of the GyroPTO absorber has been derived. •Rational approximations are performed on the radiation damping moments. •Synchronization of the device is more easily maintained...

  5. Increasing power and life expectancy from the standpoint of the regulating authorities

    International Nuclear Information System (INIS)

    Naegelin, R.; Gilli, R.; Prantl, G.; Voumard, A.

    1990-01-01

    As far as the regulating authorities are concerned, there are no arguments against increasing the power of a nuclear power plant; but each case must be assessed individually, using all criteria in the light of the current state of knowledge. Nor are there any general reasons for limiting life expectancy at existing power stations to 20, 30 or even 40 years. Safety must be monitored constantly and operations cut back if necessary. 2 figs

  6. Simulating the effect of high column density absorbers on the one-dimensional Lyman α forest flux power spectrum

    Science.gov (United States)

    Rogers, Keir K.; Bird, Simeon; Peiris, Hiranya V.; Pontzen, Andrew; Font-Ribera, Andreu; Leistedt, Boris

    2018-03-01

    We measure the effect of high column density absorbing systems of neutral hydrogen (H I) on the one-dimensional (1D) Lyman α forest flux power spectrum using cosmological hydrodynamical simulations from the Illustris project. High column density absorbers (which we define to be those with H I column densities N(H I) > 1.6 × 10^{17} atoms cm^{-2}) cause broadened absorption lines with characteristic damping wings. These damping wings bias the 1D Lyman α forest flux power spectrum by causing absorption in quasar spectra away from the location of the absorber itself. We investigate the effect of high column density absorbers on the Lyman α forest using hydrodynamical simulations for the first time. We provide templates as a function of column density and redshift, allowing the flexibility to accurately model residual contamination, i.e. if an analysis selectively clips out the largest damping wings. This flexibility will improve cosmological parameter estimation, for example, allowing more accurate measurement of the shape of the power spectrum, with implications for cosmological models containing massive neutrinos or a running of the spectral index. We provide fitting functions to reproduce these results so that they can be incorporated straightforwardly into a data analysis pipeline.

  7. Effect of thermal management on the properties of saturable absorber mirrors in high-power mode-locked semiconductor disk lasers

    International Nuclear Information System (INIS)

    Rantamäki, Antti; Lyytikäinen, Jari; Jari Nikkinen; Okhotnikov, Oleg G

    2011-01-01

    The thermal management of saturable absorbers is shown to have a critical impact on a high-power mode-locked disk laser. The absorber with efficient heat removal makes it possible to generate ultrashort pulses with high repetition rates and high power density.

  8. IAEA activities in support of rising expectation to the role of nuclear power in developing countries

    International Nuclear Information System (INIS)

    Omoto, A.

    2006-01-01

    The Paris Conference N uclear energy for the 21st Century , which was held in March 2005 organized by the IAEA, is a strong indication of the interest in the role of nuclear power. At this conference, rising expectations were indicated as representatives from many countries expressed recognition of the potential of nuclear energy to meet their energy needs in a sustainable manner. A similar indication was recognized by the June 2004 Conference held by the IAEA in Obninsk, Russia, to celebrate 50 years of nuclear electricity production. Many developing countries that currently do not operate a nuclear power plant are expressing their view that nuclear power is an important option in their energy planning in order to alleviate energy price instability, to secure long-term energy supply and to achieve an energy mix that assures sustainability. India, China and other developing countries in Asia have ambitious nuclear power deployment programmes in order to support growing energy demand and per capita energy consumption. The IAEA has a mandate to secure the benefit of the peaceful use of nuclear technology for sustainability while working against the misuse of nuclear material. Under this mandate, many guidance documents have been prepared and various technical cooperation projects are carried out to support energy planning and infrastructure building to prepare for and to sustain nuclear power operation. Basically, the IAEA can provide support by four types of activities; a) helping the process in various stages, b) helping informed decision-making through providing analytical tools and publishing technical documents, and c) reducing institutional impediments through regional cooperation, multi-national arrangement and others; and d) supporting collaborative assessments and research toward development of nuclear plants and their applications. The paper describes the observed rising expectation and the IAEA's activities in response to the rising expectation of the role

  9. Expected changes in competency assurance at Bruce Power over next decade

    Energy Technology Data Exchange (ETDEWEB)

    Horton, C., E-mail: chip.horton@brucepower.com [Bruce Power, Tiverton, Ontario (Canada)

    2013-07-01

    There will be ten expected changes in competency assurance at Bruce Power over next decade. These changes are: outage worker supplemental staff change; entry level power worker union staff; self-paced process & software training; electronic confirmation of qualifications; JIT built into processes for low frequency tasks; more terminal objective back to fundamentals vs fundamentals build to terminal objective instructional design; more learning by practice / doing in a safe environment; SAT emphasis move from analysis, design & development to evaluation & maintenance of task lists (clearly tied to working rights); more formal tacit knowledge capture programs, systematic movement of knowledge from tacit to explicit; more breadth & depth training driven by demographic changes.

  10. Expected changes in competency assurance at Bruce Power over next decade

    International Nuclear Information System (INIS)

    Horton, C.

    2013-01-01

    There will be ten expected changes in competency assurance at Bruce Power over next decade. These changes are: outage worker supplemental staff change; entry level power worker union staff; self-paced process & software training; electronic confirmation of qualifications; JIT built into processes for low frequency tasks; more terminal objective back to fundamentals vs fundamentals build to terminal objective instructional design; more learning by practice / doing in a safe environment; SAT emphasis move from analysis, design & development to evaluation & maintenance of task lists (clearly tied to working rights); more formal tacit knowledge capture programs, systematic movement of knowledge from tacit to explicit; more breadth & depth training driven by demographic changes.

  11. Community attitudes toward a proposed nuclear power generating facility as a function of expected outcomes

    International Nuclear Information System (INIS)

    Sundstrom, E.; Lounsbury, J.W.; Schuller, C.R.; Fowler, J.R.; Mattingly, T.J. Jr.

    1977-01-01

    The relationship between attitudes toward a proposed nuclear power generating facility and the outcomes expected to accompany it are examined. In a survey of 350 residents of a small rural community, approximately 2/3 expressed favorable attitudes toward the proposed nuclear plant. A principal components factor analysis of the anticipated likelihoods of outcomes of the plant revealed five factors: hazards, economic growth, lower costs, social disruption, and community visibility. Using these factors as predictors, a simple multiple regression equation accounted for 52% of the variation in attitudes toward the plant. The strongest predictor was the perceived likelihood of hazards. These findings are discussed in terms of the relationship between attitudes and expectations, and in relation to decisions regarding public policy

  12. Expected Power-Utility Maximization Under Incomplete Information and with Cox-Process Observations

    International Nuclear Information System (INIS)

    Fujimoto, Kazufumi; Nagai, Hideo; Runggaldier, Wolfgang J.

    2013-01-01

    We consider the problem of maximization of expected terminal power utility (risk sensitive criterion). The underlying market model is a regime-switching diffusion model where the regime is determined by an unobservable factor process forming a finite state Markov process. The main novelty is due to the fact that prices are observed and the portfolio is rebalanced only at random times corresponding to a Cox process where the intensity is driven by the unobserved Markovian factor process as well. This leads to a more realistic modeling for many practical situations, like in markets with liquidity restrictions; on the other hand it considerably complicates the problem to the point that traditional methodologies cannot be directly applied. The approach presented here is specific to the power-utility. For log-utilities a different approach is presented in Fujimoto et al. (Preprint, 2012).

  13. Cosmic microwave background power spectrum estimation and map reconstruction with the expectation-maximization algorithm

    Science.gov (United States)

    Martínez-González, E.; Diego, J. M.; Vielva, P.; Silk, J.

    2003-11-01

    We apply the iterative expectation-maximization algorithm (EM) to estimate the power spectrum of the cosmic microwave background (CMB) from multifrequency microwave maps. In addition, we are also able to provide a reconstruction of the CMB map. By assuming that the combined emission of the foregrounds plus the instrumental noise is Gaussian distributed in Fourier space, we have simplified the EM procedure, finding an analytical expression for the maximization step. By using the simplified expression, the CPU time can be greatly reduced. We test the stability of our power spectrum estimator with realistic simulations of Planck data, including point sources and allowing for spatial variation of the frequency dependence of the Galactic emissions. Without prior information about any of the components, our new estimator can recover the CMB power spectrum up to scales l~ 1500 with less than 10 per cent error. This result is significantly improved if the brightest point sources are removed before applying our estimator. In this way, the CMB power spectrum can be recovered up to l~ 1700 with 10 per cent error and up to l~ 2100 with 50 per cent error. This result is very close to the one that would be obtained in the ideal case of only CMB plus white noise, for which all our assumptions are satisfied. Moreover, the EM algorithm also provides a straightforward mechanism for reconstructing the CMB map. The recovered cosmological signal shows a high degree of correlation (r= 0.98) with the input map and low residuals.

  14. Analysis of mobile phone design features affecting radiofrequency power absorbed in a human head phantom.

    Science.gov (United States)

    Kuehn, Sven; Kelsh, Michael A; Kuster, Niels; Sheppard, Asher R; Shum, Mona

    2013-09-01

    The US FCC mandates the testing of all mobile phones to demonstrate compliance with the rule requiring that the peak spatial SAR does not exceed the limit of 1.6 W/kg averaged over any 1 g of tissue. These test data, measured in phantoms with mobile phones operating at maximum antenna input power, permitted us to evaluate the variation in SARs across mobile phone design factors such as shape and antenna design, communication technology, and test date (over a 7-year period). Descriptive statistical summaries calculated for 850 MHz and 1900 MHz phones and ANOVA were used to evaluate the influence of the foregoing factors on SARs. Service technology accounted for the greatest variability in compliance test SARs that ranged from AMPS (highest) to CDMA, iDEN, TDMA, and GSM (lowest). However, the dominant factor for SARs during use is the time-averaged antenna input power, which may be much less than the maximum power used in testing. This factor is largely defined by the communication system; e.g., the GSM phone average output can be higher than CDMA by a factor of 100. Phone shape, antenna type, and orientation of a phone were found to be significant but only on the order of up to a factor of 2 (3 dB). The SAR in the tilt position was significantly smaller than for touch. The side of the head did not affect SAR levels significantly. Among the remaining factors, external antennae produced greater SARs than internal ones, and brick and clamshell phones produced greater SARs than slide phones. Assuming phone design and usage patterns do not change significantly over time, we have developed a normalization procedure and formula that permits reliable prediction of the relative SAR between various communication systems. This approach can be applied to improve exposure assessment in epidemiological research. Copyright © 2013 Wiley Periodicals, Inc.

  15. Multi criteria analysis with regards to selecting optimal absorbent supply option to Ugljevik thermal power plant

    Directory of Open Access Journals (Sweden)

    Stojanović Cvjetko P.

    2015-01-01

    Full Text Available Concept of sustainable development implies an effective long-term development, both in developed and developing countries, and must be based on three pillars: environmental protection, economic development and social cohesion, both on the state and on a global level. This clear definition of sustainable development suggests a necessity of a combined action on environmental protection, economic development and the achievement of social cohesion. As a rule, by investing in environmental protection projects, power generation companies implement previously defined growth targets, development policies, and business strategies. Investment projects for the given coal type are considered as the capital ones, for they use great financial resources, significant resources and are long-lasting. The companies untertake investing in such projects to be affirmed in the new business environment, adapt to anticipated changes or to overcome the handicaps of their current position and thus adjust their production capabilities with the opportunities offered by the market. All the above implies that environmentally based capital project investments are the prerequisite of existence, sustainable growth and the acquisition of competitive advantages. However, investing in such projects is a very complex process comprised of multidimensional testing activities of all relevant determinants of future conditions and changes that the project entails. Bearing in mind that such projects are associated with the company's strategic development objectives, in the realization of such projects all the internal and external factors of development shall be taken into account, as well as a number of constraints arising from the socio-economic environment.

  16. Widely power-tunable polarization-independent ultrafast mode-locked fiber laser using bulk InN as saturable absorber.

    Science.gov (United States)

    Jimenez-Rodriguez, M; Monteagudo-Lerma, L; Monroy, E; González-Herráez, M; Naranjo, F B

    2017-03-06

    The growing demand of ultrafast mode-locked fiber lasers in the near infrared has boosted the research activity in this area. One of the most convenient ways to achieve passive mode locking consists of inserting a semiconductor saturable absorber in the laser cavity to modulate the losses. However, in such a configuration, the limited power range of operation is still an unsolved issue. Here we report the fabrication of an ultrafast, high-power, widely power-tunable and non-polarization-dependent mode-locked fiber laser operating at 1.55 µm, using an InN layer as saturable absorber. With post-amplification, this laser delivers 55-fs pulses with a repetition rate of 4.84 MHz and peak power in the range of 1 MW in an all-fiber arrangement.

  17. Shock absorber

    International Nuclear Information System (INIS)

    Housman, J.J.

    1978-01-01

    A shock absorber is described for use in a hostile environment at the end of a blind passage for absorbing impact loads. The shock absorber includes at least one element which occupies the passage and which is comprised of a porous brittle material which is substantially non-degradable in the hostile environment. A void volume is provided in the element to enable the element to absorb a predetermined level of energy upon being crushed due to impact loading

  18. Nuclear reactor core having nuclear fuel and composite burnable absorber arranged for power peaking and moderator temperature coefficient control

    International Nuclear Information System (INIS)

    Kapil, S.K.

    1991-01-01

    This patent describes a nuclear reactor core. It comprises a first group of fuel rods containing fissionable material and being free of burnable absorber material; and a second group of fuel rods containing fissionable material and first and second burnable absorber material; the first burnable absorber material being a boron-bearing material which does not contain erbium and the second burnable absorber material being an erbium material; the first and second burnable absorber materials being in the form of an outer coating on the fissionable material, the outer coating being composed of an inner layer of one of the boron-bearing material which does not contain erbium and the erbium material and an outer layer of the other of the boron-bearing material which does not contain erbium and the erbium material

  19. Progress and expectations in the field of conventional power plant technology

    International Nuclear Information System (INIS)

    Simon, M.; Harder, H.

    1993-01-01

    By increasing the medium temperature of the heat supply the efficiency of the power plants will be increased and the CO 2 emission reduced. In this respect three development lines are being followed. They are: - Further development of the high temperature process, - pressure loaded processes with fluidized-bed combustion, - combined cycle power plants with coal gasification. (DG) [de

  20. Absorber for terahertz radiation management

    Science.gov (United States)

    Biallas, George Herman; Apeldoorn, Cornelis; Williams, Gwyn P.; Benson, Stephen V.; Shinn, Michelle D.; Heckman, John D.

    2015-12-08

    A method and apparatus for minimizing the degradation of power in a free electron laser (FEL) generating terahertz (THz) radiation. The method includes inserting an absorber ring in the FEL beam path for absorbing any irregular THz radiation and thus minimizes the degradation of downstream optics and the resulting degradation of the FEL output power. The absorber ring includes an upstream side, a downstream side, and a plurality of wedges spaced radially around the absorber ring. The wedges form a scallop-like feature on the innermost edges of the absorber ring that acts as an apodizer, stopping diffractive focusing of the THz radiation that is not intercepted by the absorber. Spacing between the scallop-like features and the shape of the features approximates the Bartlett apodization function. The absorber ring provides a smooth intensity distribution, rather than one that is peaked on-center, thereby eliminating minor distortion downstream of the absorber.

  1. The power of belief and expectancy in understanding and management of depression.

    Science.gov (United States)

    Alladin, Assen

    2013-01-01

    This article examines how beliefs can influence the definition, classification, understanding, and treatment of depression. It is organized in five parts: The first part critically reviews the definition of depression; the second part explores the medicalization of depression; the third part examines the role of the pharmaceutical industry in the promotion and marketing of antidepressant medications; the fourth part surveys the psychological therapies for depression and examines the role of expectancy in outcome; and the last part looks at the mechanisms involved in the placebo effect. A list of evidence-based strategies, including hypnosis, are discussed in the context of cognitive hypnotherapy for depression to illustrate how expectancy effect can be maximized in psychotherapy.

  2. Estimation for Expected Energy Not Served of Power Systems Using the Screening Methodology of Cascading Outages in South Korea

    Directory of Open Access Journals (Sweden)

    Bokyung Goo

    2017-12-01

    Full Text Available The uncertainty of complex power systems increases the possibility of large blackouts due to the expectations of physical events, such as equipment failures, protection failures, control actions failure, operator error, and cyber-attacks. Cascading outage is a sequence of dependent failures of individual components that successively weaken the power system. A procedure to identify and evaluate the initiating events and perform sequential cascading analysis is needed. In this paper, we propose a new screening methodology based on sequential contingency simulation of cascading outages, including probabilistic analysis and visualization model. Performance of a detail cascading analysis using practical power systems is suggested and discussed. The proposed screening methodology will play a key role in identifying the uncontrolled successive loss of system elements.

  3. Schwarzschild black holes as unipolar inductors: Expected electromagnetic power of a merger

    International Nuclear Information System (INIS)

    Lyutikov, Maxim

    2011-01-01

    The motion of a Schwarzschild black hole with velocity v 0 =β 0 c through a constant magnetic field B 0 in vacuum induces a component of the electric field along the magnetic field, generating a nonzero second Poincare electromagnetic invariant * F·F≠0. This will produce (e.g., via radiative effects and vacuum breakdown) an electric charge density of the order of ρ ind =B 0 β 0 /(2πeR G ), where R G =2GM/c 2 is the Schwarzschild radius and M is the mass of the black hole; the charge density ρ ind is similar to the Goldreich-Julian density. The magnetospheres of moving black holes resemble in many respects the magnetospheres of rotationally-powered pulsars, with pair formation fronts and outer gaps, where the sign of the induced charge changes. As a result, the black hole will generate bipolar electromagnetic jets each consisting of two counter-aligned current flows (four current flows total), each carrying an electric current of the order I≅eB 0 R G β 0 . The electromagnetic power of the jets is L≅(GM) 2 B 0 2 β 0 2 /c 3 ; for a particular case of merging black holes the resulting Poynting power is L≅(GM) 3 B 0 2 /(c 5 R), where R is the radius of the orbit. In addition, in limited regions near the horizon the first electromagnetic invariant changes sign, so that the induced electric field becomes larger than the magnetic field, E>B. As a result, there will be local dissipation of the magnetic field close to the horizon, within a region with the radial extent ΔR≅R G β 0 . The total energy loss from a system of merging black holes is a sum of two components with similar powers, one due to the rotation of space-time within the orbit, driven by the nonzero angular momentum in the system, and the other due to the linear motion of the black holes through the magnetic field. Since the resulting electrodynamics is in many respects similar to pulsars, merging black holes may generate coherent radio and high energy emission beamed approximately along the

  4. Sound Absorbers

    Science.gov (United States)

    Fuchs, H. V.; Möser, M.

    Sound absorption indicates the transformation of sound energy into heat. It is, for instance, employed to design the acoustics in rooms. The noise emitted by machinery and plants shall be reduced before arriving at a workplace; auditoria such as lecture rooms or concert halls require a certain reverberation time. Such design goals are realised by installing absorbing components at the walls with well-defined absorption characteristics, which are adjusted for corresponding demands. Sound absorbers also play an important role in acoustic capsules, ducts and screens to avoid sound immission from noise intensive environments into the neighbourhood.

  5. Financing arrangements for nuclear power projects - past and present experience and future expectations

    International Nuclear Information System (INIS)

    Ispas, G.

    2004-01-01

    The intent of the author of the present paper is to demonstrate, in a practical manner, the role of the past experience and the new approaches of the nuclear projects financing, especially as nuclear generation financing in developing countries involves complex issues that need to be fully understood and dealt with by all the parties involved, namely: high investment costs, generally long construction periods, a high degree of uncertainty with respect to costs and schedule and to public acceptance, particularly because of safety, waste disposal and non-proliferation issues. Moreover, as many associations whose activities consist of ensuring and facilitating at different levels the exchange of knowledge between generations, i.e.: European Nuclear Society (ENS) Young Generation, North American Young Generation in Nuclear (NA-YGN), the goal of the paper is also to outline the importance of the education in nuclear field, i.e. training a young team of specialists to be ready to take over the movement and responsibility in continuing the further development of nuclear program in Romania, mainly with view to the Financing Arrangements for Nuclear Power Projects. The first part of the paper is referring to general financing procedures, while the second part is focusing on a case study related to the: past experience the financing scheme of Cernavoda NPP Unit 1, present or actual experience ongoing financing issues for Cernavoda NPP Unit 2 and potential future shared contribution to the financing of the next Cernavoda NPP units.(author)

  6. Trend analysis of the power law process using Expectation-Maximization algorithm for data censored by inspection intervals

    International Nuclear Information System (INIS)

    Taghipour, Sharareh; Banjevic, Dragan

    2011-01-01

    Trend analysis is a common statistical method used to investigate the operation and changes of a repairable system over time. This method takes historical failure data of a system or a group of similar systems and determines whether the recurrent failures exhibit an increasing or decreasing trend. Most trend analysis methods proposed in the literature assume that the failure times are known, so the failure data is statistically complete; however, in many situations, such as hidden failures, failure times are subject to censoring. In this paper we assume that the failure process of a group of similar independent repairable units follows a non-homogenous Poisson process with a power law intensity function. Moreover, the failure data are subject to left, interval and right censoring. The paper proposes using the likelihood ratio test to check for trends in the failure data. It uses the Expectation-Maximization (EM) algorithm to find the parameters, which maximize the data likelihood in the case of null and alternative hypotheses. A recursive procedure is used to solve the main technical problem of calculating the expected values in the Expectation step. The proposed method is applied to a hospital's maintenance data for trend analysis of the components of a general infusion pump.

  7. Development of methodology for assessment of absorbed dose and stopping power for low energy conversion electrons; Desenvolvimento de uma metodologia para estimativa da dose absorvida e do poder de freamento para eletrons de conversao de baixa energia

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Ivan Pedro Salati de

    1995-08-01

    The evaluation of absorbed dose in the case of external and internalcontamination due to radionuclides is sometimes hard, because of the difficulties in the assessment of the absorbed dose caused by electrons with energy less than 100 KeV in mucous membrane. In this work, a methodology for assessment of absorbed dose and stopping power in VYNS (co-polymer of polivinyl chloride - acetate) absorbers, for the 62.5 KeV and 84-88 KeV energy {sup 109} Cd conversion electrons, working with a 4 {pi} proportional pressurized detector, is presented. In order to assure the reproducibility of measurement conditions, one of the detector halves has been used to obtain a spectrum of a thin {sup 109} Cd source, without absorber. The other half of the detector was used in concomitance to obtain spectra with different thicknesses if absorber. The absorbed energy was obtained subtracting each spectrum with absorber from the spectrum without absorber, which were stored in a microcomputer connected to signal processing systems by ACE type interface. The VYNS weight and thickness were evaluated using common radionuclide metrology procedures. As VYNS has characteristics similar to a tissue equivalent material, the results obtained are consistent with dosimetric concepts and have a good agreement with those of the literature. (author)

  8. Comparison Between Numerical Modeling and Experimental Testing of a Point Absorber WEC Using Linear Power Take-Off System

    DEFF Research Database (Denmark)

    Zurkinden, Andrew Stephen; Kramer, Morten; Sichani, Mahdi Teimouri

    2012-01-01

    and the response of the device for regular and irregular waves were measured. Good correspondence is found between the numerical and the physical model for relatively mild wave conditions. For higher waves the numerical model seems to underestimate the response of the device due to its linear fluidstructure......Currently, a number of wave energy converters are being analyzed by means of numerical models in order to predict the electrical power generation under given wave conditions. A common characteristic of this procedure is to integrate the loadings from the hydrodynamics, power take-off and mooring...... systems into a central wave to wire model. The power production then depends on the control strategy which is applied to the device. The objective of this paper is to develop numerical methods for motion analysis of marine structures with a special emphasis on wave energy converters. Two different time...

  9. State of the art on nuclear heating measurement methods and expected improvements in zero power research reactors

    Directory of Open Access Journals (Sweden)

    Le Guillou Mael

    2017-01-01

    Full Text Available The paper focuses on the recent methodological advances suitable for nuclear heating measurements in zero power research reactors. This bibliographical work is part of an experimental approach currently in progress at CEA Cadarache, aiming at optimizing photon heating measurements in low-power research reactors. It provides an overview of the application fields of the most widely used detectors, namely thermoluminescent dosimeters (TLDs and optically stimulated luminescent dosimeters. Starting from the methodology currently implemented at CEA, the expected improvements relate to the experimental determination of the neutron component, which is a key point conditioning the accuracy of photon heating measurements in mixed n–γ field. A recently developed methodology based on the use of 7Li and 6Li-enriched TLDs, precalibrated both in photon and neutron fields, is a promising approach to deconvolute the two components of nuclear heating. We also investigate the different methods of optical fiber dosimetry, with a view to assess the feasibility of online photon heating measurements, whose primary benefit is to overcome constraints related to the withdrawal of dosimeters from the reactor immediately after irradiation. Moreover, a fibered setup could allow measuring the instantaneous dose rate during irradiation, as well as the delayed photon dose after reactor shutdown. Some insights from potential further developments are given. Obviously, any improvement of the technique has to lead to a measurement uncertainty at least equal to that of the currently used methodology (∼5% at 1σ.

  10. Low Absorbance Measurements

    Science.gov (United States)

    Harris, T. D.; Williams, A. M.

    1983-10-01

    The application of low absorption measurements to dilute solute determination requires specific instrumental characteristics. The use of laser intracavity absorption and thermal lens calorimetry to measure concentration is shown. The specific operating parameters that determine sensitivity are delineated along with the limits different measurement strategies impose. Finally areas of improvement in components that would result in improve sensitivity, accuracy, and reliability are discussed. During the past decade, a large number of methods have been developed for measuring the light absorbed by transparent materials. These include measurements on gases, liquids, and solids. The activity has been prompted by a variety of applications and a similar variety of disciplines. In Table 1 some representative examples of these methods is shown along with their published detection limits.1 It is clear that extraordinarily small absorbances can be measured. Most of the methods can be conveniently divided into two groups. These groups are those that measure the transmission of the sample and those that measure the light absorbed by the sample. The light absorbed methods are calorimetric in character. The advantages and disadvantages of each method varies depending on the principal application for which they were developed. The most prevalent motivation has been to characterize the bulk optical properties of transparent materials. Two examples are the development of extremely transparent glasses for use as fiber optic materials and the development of substrates for high power laser operation.

  11. The power of positive and negative expectations to influence reported symptoms and mood during exposure to wind farm sound.

    Science.gov (United States)

    Crichton, Fiona; Dodd, George; Schmid, Gian; Gamble, Greg; Cundy, Tim; Petrie, Keith J

    2014-12-01

    Wind farm developments have been hampered by claims that sound from wind turbines causes symptoms and negative health reports in nearby residents. As scientific reviews have failed to identify a plausible link between wind turbine sound and health effects, psychological expectations have been proposed as an explanation for health complaints. Building on recent work showing negative expectations can create symptoms from wind turbines, we investigated whether positive expectations can produce the opposite effect, in terms of a reduction in symptoms and improvements in reported health. 60 participants were randomized to either positive or negative expectation groups and subsequently exposed to audible wind farm sound and infrasound. Prior to exposure, negative expectation participants watched a DVD incorporating TV footage about health effects said to be caused by infrasound produced by wind turbines. In contrast, positive expectation participants viewed a DVD that outlined the possible therapeutic effects of infrasound exposure. During exposure to audible windfarm sound and infrasound, symptoms and mood were strongly influenced by the type of expectations. Negative expectation participants experienced a significant increase in symptoms and a significant deterioration in mood, while positive expectation participants reported a significant decrease in symptoms and a significant improvement in mood. The study demonstrates that expectations can influence symptom and mood reports in both positive and negative directions. The results suggest that if expectations about infrasound are framed in more neutral or benign ways, then it is likely reports of symptoms or negative effects could be nullified.

  12. Metamaterial electromagnetic wave absorbers.

    Science.gov (United States)

    Watts, Claire M; Liu, Xianliang; Padilla, Willie J

    2012-06-19

    The advent of negative index materials has spawned extensive research into metamaterials over the past decade. Metamaterials are attractive not only for their exotic electromagnetic properties, but also their promise for applications. A particular branch-the metamaterial perfect absorber (MPA)-has garnered interest due to the fact that it can achieve unity absorptivity of electromagnetic waves. Since its first experimental demonstration in 2008, the MPA has progressed significantly with designs shown across the electromagnetic spectrum, from microwave to optical. In this Progress Report we give an overview of the field and discuss a selection of examples and related applications. The ability of the MPA to exhibit extreme performance flexibility will be discussed and the theory underlying their operation and limitations will be established. Insight is given into what we can expect from this rapidly expanding field and future challenges will be addressed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Carbon Absorber Retrofit Equipment (CARE)

    Energy Technology Data Exchange (ETDEWEB)

    Klein, Eric [Neumann Systems Group, Incorporated, Colorado Springs, CO (United States)

    2015-12-23

    During Project DE-FE0007528, CARE (Carbon Absorber Retrofit Equipment), Neumann Systems Group (NSG) designed, installed and tested a 0.5MW NeuStream® carbon dioxide (CO2) capture system using the patented NeuStream® absorber equipment and concentrated (6 molal) piperazine (PZ) as the solvent at Colorado Springs Utilities’ (CSU’s) Martin Drake pulverized coal (PC) power plant. The 36 month project included design, build and test phases. The 0.5MW NeuStream® CO2 capture system was successfully tested on flue gas from both coal and natural gas combustion sources and was shown to meet project objectives. Ninety percent CO2 removal was achieved with greater than 95% CO2product purity. The absorbers tested support a 90% reduction in absorber volume compared to packed towers and with an absorber parasitic power of less than 1% when configured for operation with a 550MW coal plant. The preliminary techno-economic analysis (TEA) performed by the Energy and Environmental Research Center (EERC) predicted an over-the-fence cost of $25.73/tonne of CO2 captured from a sub-critical PC plant.

  14. Heterogeneous neutron absorbers development

    International Nuclear Information System (INIS)

    Boccaccini, Aldo; Agueda, Horacio; Russo, Diego; Perez, Edmundo

    1987-01-01

    The use of solid burnable absorber materials in power light water reactors has increased in the last years, specially due to improvements attained in costs of generated electricity. The present work summarizes the basic studies made on an alumina-gadolinia system, where alumina is the inert matrix and gadolinia acts as burnable poison, and describes the fabrication method of pellets with that material. High density compacts were obtained in the range of concentrations used by cold pressing and sintering at 1600 deg C in inert (Ar) atmosphere. Finally, the results of the irradiation experiences made at RA-6 reactor, located at the Bariloche Atomic Center, are given where variations on negative reactivity caused by introduction of burnable poison rods were measured. The results obtained from these experiences are in good agreement with those coming from calculation codes. (Author)

  15. An omnidirectional electromagnetic absorber made of metamaterials

    International Nuclear Information System (INIS)

    Cheng Qiang; Cui Tiejun; Jiang Weixiang; Cai Bengeng

    2010-01-01

    In a recent theoretical work by Narimanov and Kildishev (2009 Appl. Phys. Lett. 95 041106) an optical omnidirectional light absorber based on metamaterials was proposed, in which theoretical analysis and numerical simulations showed that all optical waves hitting the absorber are trapped and absorbed. Here we report the first experimental demonstration of an omnidirectional electromagnetic absorber in the microwave frequency. The proposed device is composed of non-resonant and resonant metamaterial structures, which can trap and absorb electromagnetic waves coming from all directions spirally inwards without any reflections due to the local control of electromagnetic fields. It is shown that the absorption rate can reach 99 per cent in the microwave frequency. The all-directional full absorption property makes the device behave like an 'electromagnetic black body', and the wave trapping and absorbing properties simulate, to some extent, an 'electromagnetic black hole.' We expect that such a device could be used as a thermal emitting source and to harvest electromagnetic waves.

  16. Bend-absorbing clamp

    Science.gov (United States)

    Abbott, J. R.; Valencia, B., Jr.

    1979-01-01

    Compact, inexpensive clamp for flexible cables or rigid tubes absorbs vibrations and other motion. It accomodates wide range of dimensions, and saves space by eliminating pigtails or bellows commonly used to absorb linear movement or vibrations

  17. Optically Modulated Multiband Terahertz Perfect Absorber

    DEFF Research Database (Denmark)

    Seren, Huseyin R.; Keiser, George R.; Cao, Lingyue

    2014-01-01

    response of resonant metamaterials continues to be a challengingendeavor. Resonant perfect absorbers have flourished as one of the mostpromising metamaterial devices with applications ranging from power har-vesting to terahertz imaging. Here, an optically modulated resonant perfectabsorber is presented...

  18. Recoverable neutron absorbers

    International Nuclear Information System (INIS)

    Keay, R.T.; Williams, J.A.

    1982-01-01

    In the reprocessing of irradiated nuclear fuel elements the nuclear fuel material is separated from the material which forms the remainder of the elements by dissolving the nuclear fuel material in nitric acid. Neutron absorbers are added to control criticality. The neutron absorbers comprise pellets each having a core of neutron absorbing material encased in a sheath of a material which is resistant to attack by acid, the core or sheath being magnetic. The sheath protects the core of neutron absorbing material from attack by the acid and the magnetic content of the core or sheath enables the absorbers to be recovered for reuse by magnetic separation techniques. (author)

  19. An experimental study of an energy absorbing restrainer for piping systems

    International Nuclear Information System (INIS)

    Sone, A.; Suzuki, K.

    1989-01-01

    Recently, in the seismic design methodology of the piping systems in nuclear power plants, new and improved design criteria and calculation techniques which will lead to more reliable and cost saving design products have been investigated. For instance, problems for reducing the snubbers in nuclear power plants which provide high costs for their inspections and maintenances and related flexible design problems for the dynamic piping systems have been investigated. Thus, in order to replace snubbers, various types of alternative supporting devices such as dynamic absorbers, gapped support and energy absorbing support devices have been proposed. A number of energy absorbing restrainers have been designed in Japan and United-States by allowing yield to occur during strong earthquakes. Advantages and disadvantages of these restrainers were examined analytically and experimentally. In order to overcome the disadvantages, the authors introduced new absorbing material LSPZ (laminated super plastic zinc) in which SPZ is expected to have reliable ductility and also efficient energy absorbability still under the normal temperature condition. This paper is devoted to an experimental works for this updated absorbing restrainer

  20. General discrete random walk with variable absorbing probabilities

    OpenAIRE

    van Uem, Theo

    2009-01-01

    We obtain expected number of arrivals, probability of arrival, absorption probabilities and expected time before absorption for a general discrete random walk with variable absorbing probabilities on a finite interval using Fibonacci numbers

  1. Unequal Expectations

    DEFF Research Database (Denmark)

    Karlson, Kristian Bernt

    the impact of educational tracking on expectation formation among high school students in the U.S., whereas Chapter III analyzes the role of the grade point average in the expectation formation process among socially disadvantaged high school students in the U.S. The empirical analyses in both chapters...

  2. The effect of political cycles on power investment decisions: Expectations over the repeal and reinstatement of carbon policy mechanisms in Australia

    International Nuclear Information System (INIS)

    ShahNazari, Mahdi; McHugh, Adam; Maybee, Bryan; Whale, Jonathan

    2014-01-01

    Highlights: • Effect of political cycles quantified in power generation investments. • Expected repeal and reinstatement of carbon policy modelled dynamically. • A survey of experts informed the decision making model. • Expectations over reinstatement of policy dampens the effect of expected repeal. - Abstract: Political uncertainty over global greenhouse gas (GHG) mitigation policy is likely to defer investment in cleaner technologies. It may also incentivise short-lived, high-cost interim investments while businesses wait for the uncertainty to subside. The range of possible policy responses to the issue has created uncertainty over the future of national mitigation pathways. Given that the electricity sector, globally, is a major emitter of GHGs, this represents a systematic risk to investment in electricity generation assets. This paper uses a real options analysis framework informed by a survey of experts conducted in Australia – used as a proxy to model the degree of the uncertainty – to investigate the optimal timing for investment in the conversion of a coal plant to a combined cycle gas turbine plant using the American-style option valuation method. The effect of market and political uncertainty is studied for the Clean Energy Act 2011 in Australia. Political uncertainty is addressed bi-modally in terms of: (1) uncertainty over the repeal of the carbon pricing policy, and (2) if it is repealed, uncertainty over the reinstatement of the policy, to represent the effect of electoral cycles and the possibility of more stringent future global mitigation efforts. Results of the analysis show that although political uncertainty with respect to GHG mitigation policy may delay investment in the conversion of the coal plant, expectations over the reinstatement of the carbon pricing reduces the amount of option premium to defer the conversion decision

  3. Evolutionary Expectations

    DEFF Research Database (Denmark)

    Nash, Ulrik William

    2014-01-01

    , they are correlated among people who share environments because these individuals satisfice within their cognitive bounds by using cues in order of validity, as opposed to using cues arbitrarily. Any difference in expectations thereby arise from differences in cognitive ability, because two individuals with identical......The concept of evolutionary expectations descends from cue learning psychology, synthesizing ideas on rational expectations with ideas on bounded rationality, to provide support for these ideas simultaneously. Evolutionary expectations are rational, but within cognitive bounds. Moreover...... cognitive bounds will perceive business opportunities identically. In addition, because cues provide information about latent causal structures of the environment, changes in causality must be accompanied by changes in cognitive representations if adaptation is to be maintained. The concept of evolutionary...

  4. Unequal Expectations

    DEFF Research Database (Denmark)

    Karlson, Kristian Bernt

    In this dissertation I examine the relationship between subjective beliefs about the outcomes of educational choices and the generation of inequality of educational opportunity (IEO) in post-industrial society. Taking my departure in the rational action turn in the sociology of educational...... different educational choices according to their family background. IEO thus appears to be mediated by the expectations students hold for their futures. Taken together, this research agenda argues that both researchers and policy-makers need to consider the expectation-based origin of educational...... for their educational futures. Focusing on the causes rather than the consequences of educational expectations, I argue that students shape their expectations in response to the signals about their academic performance they receive from institutionalized performance indicators in schools. Chapter II considers...

  5. Study on large scale knowledge base with real time operation for autonomous nuclear power plant. 1. Basic concept and expecting performance

    International Nuclear Information System (INIS)

    Ozaki, Yoshihiko; Suda, Kazunori; Yoshikawa, Shinji; Ozawa, Kenji

    1996-04-01

    Since it is desired to enhance availability and safety of nuclear power plants operation and maintenance by removing human factor, there are many researches and developments for intelligent operation or diagnosis using artificial intelligence (AI) technique. We have been developing an autonomous operation and maintenance system for nuclear power plants by substituting AI's and intelligent robots. It is indispensable to use various and large scale knowledge relative to plant design, operation, and maintenance, that is, whole life cycle data of the plant for the autonomous nuclear power plant. These knowledge must be given to AI system or intelligent robots adequately and opportunely. Moreover, it is necessary to insure real time operation using the large scale knowledge base for plant control and diagnosis performance. We have been studying on the large scale and real time knowledge base system for autonomous plant. In the report, we would like to present the basic concept and expecting performance of the knowledge base for autonomous plant, especially, autonomous control and diagnosis system. (author)

  6. Calculation of absorbed dose for skin contamination imparted by beta radiation through the VARSKIN modified code for 122 interesting isotopes for nuclear medicine, nuclear power plants and research

    International Nuclear Information System (INIS)

    Alvarez R, J.T.

    1991-01-01

    In this work the implementation of a modification of the VARSKIN code for calculation of absorbed dose for contamination in skin imparted by external radiation fields generated by Beta emitting is presented. The modification consists on the inclusion of 47 isotopes of interest even Nuclear Plants for the dose evaluation in skin generated by 'hot particles'. The approach for to add these isotopes is the correlation parameter F and the average energy of the Beta particle, with relationship to those 75 isotopes of the original code. The methodology of the dose calculation of the VARSKIN code is based on the interpolation, (and integration of the interest geometries: punctual or plane sources), of the distribution functions scaled doses in water for beta and electrons punctual sources, tabulated by Berger. Finally a brief discussion of the results for their interpretation and use with purposes of radiological protection (dose insurance in relation to the considered biological effects) is presented

  7. Great Expectations

    NARCIS (Netherlands)

    Dickens, Charles

    2005-01-01

    One of Dickens's most renowned and enjoyable novels, Great Expectations tells the story of Pip, an orphan boy who wishes to transcend his humble origins and finds himself unexpectedly given the opportunity to live a life of wealth and respectability. Over the course of the tale, in which Pip

  8. Absorber manufacturing made easy

    Energy Technology Data Exchange (ETDEWEB)

    Berner, Joachim

    2010-07-01

    Whether by means of a laser source or an ultrasound head - automation technology is making progress in the solar thermal sector. S and WE presents news developments in welding technology in absorber manufacture. (orig.)

  9. PWR burnable absorber evaluation

    International Nuclear Information System (INIS)

    Cacciapouti, R.J.; Weader, R.J.; Malone, J.P.

    1995-01-01

    The purpose of the study was to evaluate the relative neurotic efficiency and fuel cycle cost benefits of PWR burnable absorbers. Establishment of reference low-leakage equilibrium in-core fuel management plans for 12-, 18- and 24-month cycles. Review of the fuel management impact of the integral fuel burnable absorber (IFBA), erbium and gadolinium. Calculation of the U 3 O 8 , UF 6 , SWU, fuel fabrication, and burnable absorber requirements for the defined fuel management plans. Estimation of fuel cycle costs of each fuel management plan at spot market and long-term market fuel prices. Estimation of the comparative savings of the different burnable absorbers in dollar equivalent per kgU of fabricated fuel. (author)

  10. TOMS Absorbing Aerosol Index

    Data.gov (United States)

    Washington University St Louis — TOMS_AI_G is an aerosol related dataset derived from the Total Ozone Monitoring Satellite (TOMS) Sensor. The TOMS aerosol index arises from absorbing aerosols such...

  11. Experiments expectations

    OpenAIRE

    Gorini, B; Meschi, E

    2014-01-01

    This paper presents the expectations and the constraints of the experiments relatively to the commissioning procedure and the running conditions for the 2015 data taking period. The views about the various beam parameters for the p-p period, like beam energy, maximum pileup, bunch spacing and luminosity limitation in IP2 and IP8, are discussed. The goals and the constraints of the 2015 physics program are also presented, including the heavy ions period as well as the special...

  12. Effect of Burnable Absorbers on Inert Matrix Fuel Performance and Transuranic Burnup in a Low Power Density Light-Water Reactor

    Directory of Open Access Journals (Sweden)

    Geoff Recktenwald

    2013-04-01

    Full Text Available Zirconium dioxide has received particular attention as a fuel matrix because of its ability to form a solid solution with transuranic elements, natural radiation stability and desirable mechanical properties. However, zirconium dioxide has a lower coefficient of thermal conductivity than uranium dioxide and this presents an obstacle to the deployment of these fuels in commercial reactors. Here we show that axial doping of a zirconium dioxide based fuel with erbium reduces power peaking and fuel temperature. Full core simulations of a modified AP1000 core were done using MCNPX 2.7.0. The inert matrix fuel contained 15 w/o transuranics at its beginning of life and constituted 28% of the assemblies in the core. Axial doping reduced power peaking at startup by more than ~23% in the axial direction and reduced the peak to average power within the core from 1.80 to 1.44. The core was able to remain critical between refueling while running at a simulated 2000 MWth on an 18 month refueling cycle. The results show that the reactor would maintain negative core average reactivity and void coefficients during operation. This type of fuel cycle would reduce the overall production of transuranics in a pressurized water reactor by 86%.

  13. Performance of Closely Spaced Point Absorbers with Constrained Floater Motion

    DEFF Research Database (Denmark)

    De Backer, G.; Vantorre, M.; Beels, C.

    2009-01-01

    The performance of a wave energy converter array of twelve heaving point absorbers has been assessed numerically in a frequency domain model. Each point absorber is assumed to have its own linear power take-off. The impact of slamming, stroke and force restrictions on the power absorption...

  14. Neutron absorbing materials for reactors control; Materiaux absorbants neutroniques pour le pilotage des reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    Gosset, D. [CEA Saclay, Dept. des Materiaux pour le Nucleaire (DMN), 91 - Gif sur Yvette (France); Herter, P. [CEA Saclay, Dir. de l' Energie Nucleaire (DEN), 91 - Gif sur Yvette (France)

    2007-01-15

    The different reactivity control systems allow to keep the mastery of the fission reaction inside the reactor core at any time: power control, safe shutdown, compensation of fuel burnup. These systems can be of different type: gaseous (like {sup 3}He in some experimental reactors), liquid (borated water in PWRs), and in most cases solid and combined or not with the previous types. In all cases, the constituents comprise neutron absorbing nuclides. The absorbing materials are contained in elementary absorbing elements, named control rods. This article describes the absorbing materials used in the control rods of the main nuclear power plants and also in the burnable poison rods of water cooled reactors. Content: 1 - general considerations about absorbing materials: neutron absorption cross sections, selection criteria of absorbing materials, main uses of absorbers in reactors, supply sources, wastes; 2 - description of the absorbing materials used: silver-indium-cadmium alloy (ICA), boron carbide (B{sub 4}C), dysprosium titanate, hafnium, burnable poisons and rare earths; 3 - conclusion and perspectives. (J.S.)

  15. Neutron absorbing article

    International Nuclear Information System (INIS)

    Naum, R.G.; Owens, D.P.; Dooher, G.I.

    1979-01-01

    A neutron absorbing article, in flat plate form and suitable for use in a storage rack for spent fuel, includes boron carbide particles, diluent particles and a solid, irreversibly cured phenolic polymer cured to a continuous matrix binding the boron carbide and diluent particles. The total conent of boron carbide and diluent particles is a major proportion of the article and the content of cured phenolic polymer present is a minor proportion. By regulation of the ratio of boron carbide particles to diluent particles, normally within the range of 1:9 and 9:1 and preferably within the range of 1:5 to 5:1, the neutron absorbing activity of the product may be controlled, which facilitates the manufacture of articles of particular absorbing activities best suitable for specific applications

  16. Neutron absorbing article

    International Nuclear Information System (INIS)

    Naum, R.G.; Owens, D.P.; Dooker, G.I.

    1981-01-01

    A neutron-absorbing article suitable for use in spent fuel racks is described. It comprises boron carbide particles, diluent particles, and a phenolic polymer cured to a continuous matrix. The diluent may be silicon carbide, graphite, amorphous carbon, alumina, or silica. The combined boron carbide-diluent phase contains no more than 2 percent B 2 O 3 , and the neutron-absorbing article contains from 20 to 40 percent phenol resin. The ratio of boron carbide to diluent particles is in the range 1:9 to 9:1

  17. Absorber for nuclear radiations

    International Nuclear Information System (INIS)

    Planchamp, C.

    1987-01-01

    Neutrons, gamma and x radiations are highly absorbed by an alloy of gadolinium and aluminium. Workability, thermal conductivity, mechanical properties, corrosion resistance of the alloy are good. Possible applications are transport or storage of radioactive wastes or nuclear fuels, fuel racks, shelters, etc [fr

  18. Energy Absorber for Vehicle Occupant Safety and Survivability

    National Research Council Canada - National Science Library

    Fox, David M

    2006-01-01

    (U) A DESIGN WAS DEVELOPED FOR A NEW TYPE OF IMPACT ENERGY ABSORBER. THIS DEVICE WOULD BE EXPECTED TO DEMONSTRATE FAVORABLE APPLICATION TO VEHICLE OCCUPANT SAFETY IN CRASH AND SECONDARY IMPACT EVENTS...

  19. Kinetic energy absorbing pad

    International Nuclear Information System (INIS)

    Bricmont, R.J.; Hamilton, P.A.; Ming Long Ting, R.

    1981-01-01

    Reactors, fuel processing plants etc incorporate pipes and conduits for fluids under high pressure. Fractures, particularly adjacent to conduit elbows, produce a jet of liquid which whips the broken conduit at an extremely high velocity. An enormous impact load would be applied to any stationary object in the conduit's path. The design of cellular, corrugated metal impact pads to absorb the kinetic energy of the high velocity conduits is given. (U.K.)

  20. Absorbable and biodegradable polymers

    CERN Document Server

    Shalaby, Shalaby W

    2003-01-01

    INTRODUCTION NOTES: Absorbable/Biodegradable Polymers: Technology Evolution. DEVELOPMENT AND APPLICATIONOF NEW SYSTEMS: Segmented Copolyesters with Prolonged Strength Retention Profiles. Polyaxial Crystalline Fiber-Forming Copolyester. Polyethylene Glycol-Based Copolyesters. Cyanoacrylate-Based Systems as Tissue Adhesives. Chitosan-Based Systems. Hyaluronic Acid-Based Systems. DEVELOPMENTS IN PREPARATIVE, PROCESSING, AND EVALUATION METHODS: New Approaches to the Synthesis of Crystalline. Fiber-Forming Aliphatic Copolyesters. Advances in Morphological Development to Tailor the Performance of Me

  1. Burnable neutron absorbers

    International Nuclear Information System (INIS)

    Radford, K.C.; Carlson, W.G.

    1985-01-01

    This patent deals with the fabrication of pellets for neutron absorber rods. Such a pellet includes a matrix of a refractory material which may be aluminum or zirconium oxide, and a burnable poison distributed throughout the matrix. The neutron absorber material may consist of one or more elements or compounds of the metals boron, gadolinium, samarium, cadmium, europium, hafnium, dysprosium and indium. The method of fabricating pellets of these materials outlined in this patent is designed to produce pores or voids in the pellets that can be used to take up the expansion of the burnable poison and to absorb the helium gas generated. In the practice of this invention a slurry of Al 2 O 3 is produced. A hard binder is added and the slurry and binder are spray dried. This powder is mixed with dry B 4 C powder, forming a homogeneous mixture. This mixture is pressed into green tubes which are then sintered. During sintering the binder volatilizes leaving a ceramic with nearly spherical high-density regions of

  2. Corrosion resistant neutron absorbing coatings

    Science.gov (United States)

    Choi, Jor-Shan [El Cerrito, CA; Farmer, Joseph C [Tracy, CA; Lee, Chuck K [Hayward, CA; Walker, Jeffrey [Gaithersburg, MD; Russell, Paige [Las Vegas, NV; Kirkwood, Jon [Saint Leonard, MD; Yang, Nancy [Lafayette, CA; Champagne, Victor [Oxford, PA

    2012-05-29

    A method of forming a corrosion resistant neutron absorbing coating comprising the steps of spray or deposition or sputtering or welding processing to form a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material. Also a corrosion resistant neutron absorbing coating comprising a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material.

  3. Solar radiation absorbing material

    Science.gov (United States)

    Googin, John M.; Schmitt, Charles R.; Schreyer, James M.; Whitehead, Harlan D.

    1977-01-01

    Solar energy absorbing means in solar collectors are provided by a solar selective carbon surface. A solar selective carbon surface is a microporous carbon surface having pores within the range of 0.2 to 2 micrometers. Such a surface is provided in a microporous carbon article by controlling the pore size. A thermally conductive substrate is provided with a solar selective surface by adhering an array of carbon particles in a suitable binder to the substrate, a majority of said particles having diameters within the range of about 0.2-10 microns.

  4. Methods for applying microchannels to separate methane using liquid absorbents, especially ionic liquid absorbents from a mixture comprising methane and nitrogen

    Science.gov (United States)

    Tonkovich, Anna Lee Y [Dublin, OH; Litt, Robert D [Westerville, OH; Dongming, Qiu [Dublin, OH; Silva, Laura J [Plain City, OH; Lamont, Micheal Jay [Plain City, OH; Fanelli, Maddalena [Plain City, OH; Simmons, Wayne W [Plain city, OH; Perry, Steven [Galloway, OH

    2011-10-04

    Methods of using microchannel separation systems including absorbents to improve thermal efficiency and reduce parasitic power loss. Energy is typically added to desorb methane and then energy or heat is removed to absorb methane using a working solution. The working solution or absorbent may comprise an ionic liquid, or other fluids that demonstrate a difference in affinity between methane and nitrogen in a solution.

  5. Heaving buoys, point absorbers and arrays.

    Science.gov (United States)

    Falnes, Johannes; Hals, Jørgen

    2012-01-28

    Absorption of wave energy may be considered as a phenomenon of interference between incident and radiated waves generated by an oscillating object; a wave-energy converter (WEC) that displaces water. If a WEC is very small in comparison with one wavelength, it is classified as a point absorber (PA); otherwise, as a 'quasi-point absorber'. The latter may be a dipole-mode radiator, for instance an immersed body oscillating in the surge mode or pitch mode, while a PA is so small that it should preferably be a source-mode radiator, for instance a heaving semi-submerged buoy. The power take-off capacity, the WEC's maximum swept volume and preferably also its full physical volume should be reasonably matched to the wave climate. To discuss this matter, two different upper bounds for absorbed power are applied in a 'Budal diagram'. It appears that, for a single WEC unit, a power capacity of only about 0.3 MW matches well to a typical offshore wave climate, and the full physical volume has, unfortunately, to be significantly larger than the swept volume, unless phase control is used. An example of a phase-controlled PA is presented. For a sizeable wave-power plant, an array consisting of hundreds, or even thousands, of mass-produced WEC units is required.

  6. 'Never expect power always': electricity consumers' response to monopoly, corruption and inefficient services in Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Ayodeji Olukoju

    2004-01-01

    The supply of electricity, undoubtedly the key energy source for industrial, commercial and domestic activity in the modern world, falls far short of demand in many developing countries. In Nigeria, state monopoly has compounded rather than resolved the energy crisis. The National Electric Power Authority (NEPA), established by decree in 1972, epitomizes the utter failure of state monopolies in the power sector. This and other state-owned enterprises have been the target of recent attempts at reform through privatization, deregulation or liberalization. This article analyzes developments in the Nigerian power sector, focusing on internal and external factors in NEPA's crisis, reform measures by successive governments, and the plight of consumers and their reactions to these circumstances, and comments on the ongoing and proposed reforms of the power sector. (author)

  7. The Flexible Bass Absorber

    DEFF Research Database (Denmark)

    Adelman-Larsen, Niels Werner; Thompson, Eric Robert; Gade, Anders Christian

    2007-01-01

    Multi-purpose concert halls face a dilemma. They host different performance types that require significantly different acoustic conditions in order to provide the best sound quality to both the performers, sound engineers and the audience. Pop and rock music often contain high levels of bass sound...... energy but still require high definition for good sound quality. The mid- and high-frequency absorption is easily regulated, but adjusting the low-frequency absorption has typically been too expensive or requires too much space to be practical for multi-purpose halls. A practical solution to this dilemma...... has been developed. Measurements were made on a variable and mobile low-frequency absorber. The paper presents the results of prototype sound absorption measurements as well as elements of the design....

  8. The Flexible Bass Absorber

    DEFF Research Database (Denmark)

    Adelman-Larsen, Niels Werner; Thompson, Eric Robert; Gade, Anders Christian

    2007-01-01

    Multi-purpose concert halls face a dilemma. They host different performance types that require significantly different acoustic conditions in order to provide the best sound quality to both the performers, sound engineers and the audience. Pop and rock music often contains high levels of bass sound...... energy but still require high definition for good sound quality. The mid- and high-frequency absorption is easily regulated, but adjusting the low-frequency absorption has typically been too expensive or requires too much space to be practical for multi-purpose halls. A practical solution to this dilemma...... has been developed. Measurements were made on a variable and mobile low-frequency absorber. The paper presents the results of prototype sound absorption measurements as well as elements of the design....

  9. Aperiodic-metamaterial-based absorber

    Directory of Open Access Journals (Sweden)

    Quanlong Yang

    2017-09-01

    Full Text Available The periodic-metamaterial-based perfect absorber has been studied broadly. Conversely, if the unit cell in the metamaterial-based absorber is arranged aperiodically (aperiodic-metamaterial-based absorber, how does it perform? Inspired by this, here we present a systematic study of the aperiodic-metamaterial-based absorber. By investigating the response of metamaterial absorbers based on periodic, Fibonacci, Thue-Morse, and quasicrystal lattices, we found that aperiodic-metamaterial-based absorbers could display similar absorption behaviors as the periodic one in one hand. However, their absorption behaviors show different tendency depending on the thicknesses of the spacer. Further studies on the angle and polarization dependence of the absorption behavior are also presented.

  10. Mission MOX Fuel Physics Design--Preliminary Equilibrium MOX Assembly Design and Expected Operating Power for Existing Balakovo Fuel Management Scheme

    Energy Technology Data Exchange (ETDEWEB)

    Pavlovichev, A.M.

    2001-09-28

    Among various versions of excess weapons-grade plutonium handling the most preferred in Russia is its burning in power reactors. This is accounted for by the desire to utilize the power value of weapons-grade plutonium and the potentialities of the existing nuclear industry complex. In Russia the versions of burning weapons-grade plutonium in the VVER-, BN-, and HTGR-type power reactors are being developed. However the analysis of the current structure of nuclear power and the energy strategy reveals that in the coming years the VVER-1000-type (designs B-320 and B-392) as well as the VVER-640 reactor (design B-407) now under development appear to be the most promising for this purpose. The experience with the use of mixed uranium/plutonium fuel in the LWR, gained in the West and the preliminary studies carried out in Russia show that weapons-grade plutonium may be actually used as fuel for the Russian VVER reactors. At present Russia has 7 operating VVER-1000 of total installed capacity 7 GWe, 11 reactors of this type are in operation in Ukraine, and 2 in Bulgaria. Before 2003 it is planned to put into operation 2 VVER-1000 units more in Russian and at least 2 units in Ukraine.

  11. Security of supply and line flow following the shut-down of nuclear power plants in Germany. Have shortages to be expected?

    International Nuclear Information System (INIS)

    Kunz, Friedrich; Moest, Dominik

    2011-01-01

    This paper, which examines the impacts of phasing out nuclear power in Germany, is the first to include an analysis of energy supply security and critical line flows in both the German and Central European electricity networks. The technical-economic model of the European electricity market, ELMOD, is used to simulate alternative power plant dispatch, imports, exports, and network use for a representative winter day. The results suggest that the shutdown of Germany's nuclear plants will result in higher net imports, especially from the Netherlands, Austria, and Poland, and that electricity generation from fossil fuels will increase slightly in Germany and in Central Europe. We find that no additional imports will come from nuclear plants since they are already fully utilized in the merit order, and that electricity prices will rise on average by a few Euros per MWh. We conclude that closing the seven nuclear power plants within the government's moratorium will cause no significant supply security issues or network constraints and an eventual full phase-out seem to be possible due to the completion of several new conventional power plants now under construction. Finally, we suggest that a nuclear phase-out in Germany within the next 3-7 years will not undermine security of supply and network stability in Germany and Central Europe.

  12. Ultra-thin and broadband tunable metamaterial graphene absorber.

    Science.gov (United States)

    Xiong, Han; Wu, Ying-Bo; Dong, Ji; Tang, Ming-Chun; Jiang, Yan-Nan; Zeng, Xiao-Ping

    2018-01-22

    A broadband tunable metamaterial graphene absorber is investigated in this paper. The unit cell of the proposed metamaterial graphene absorber is composed of four patch resonators. By tuning the chemical potential of graphene and the geometric size of each patch, the simulated total reflectivity is less than -10 dB from 22.02 to 36.61 THz and with the total thickness of 0.76 um (only 0.09λ at the lowest frequency). The analysis of the surface current, magnetic field and power flow distributions has been performed to better understand the absorption mechanism. Moreover, this proposed absorber achieves its bandwidth tunable characteristics through a voltage biasing of the graphene's Fremi level. This proposed metamaterial graphene absorber (MGA) could be used as smart absorbers, photovoltaic devices and tunable sensors.

  13. New Technology in Hydrogen Absorbers for Muon Cooling Channels

    CERN Document Server

    Cummings, M A C

    2005-01-01

    Ionization cooling is the only technique fast enough to cool and focus muons for neutrino factories and muon colliders, and hydrogen is the optimal material for maximum cooling and minimal multiple scattering. Liquid hydrogen absorber R&D for the Muon Collaboration has proceeded on parallel and complementary fronts. The continuing LH2 absorber engineering and technical developments by the MuCool group conducted by ICAR* institutions (NIU, IIT and UIUC), the University of Mississippi and Oxford University, in cooperation with Fermilab, will be summarized, including results from the first hydrogen absorber tests at the newly constructed FNAL Mucool Test Area (MTA). The program includes designs for the high-powered test of an absorber prototype (external heat exchange) at the MTA which are nearing completion to be installed by summer 2005, an alternative absorber design (internal heat exchange) being finalized for the approved cooling experiment (MICE) at Rutherford-Appleton Laboratory, and a novel idea for ...

  14. Burnable absorber coated nuclear fuel

    International Nuclear Information System (INIS)

    Chubb, W.; Radford, K.C.; Parks, B.H.

    1984-01-01

    A nuclear fuel body which is at least partially covered by a burnable neutron absorber layer is provided with a hydrophobic overcoat generally covering the burnable absorber layer and bonded directly to it. In a method for providing a UO 2 fuel pellet with a zirconium diboride burnable poison layer, the fuel body is provided with an intermediate niobium layer. (author)

  15. Metal-shearing energy absorber

    Science.gov (United States)

    Fay, R. J.; Wittrock, E. P.

    1971-01-01

    Device, consisting of tongue of thin aluminum alloy strip, pull tab, slotted steel plate which serves as cutter, and steel buckle, absorbs mechanical energy when its ends are subjected to tensile loading. Device is applicable as auxiliary shock absorbing anchor for automobile and airplane safety belts.

  16. Leaf absorbance and photosynthesis

    Science.gov (United States)

    Schurer, Kees

    1994-01-01

    The absorption spectrum of a leaf is often thought to contain some clues to the photosynthetic action spectrum of chlorophyll. Of course, absorption of photons is needed for photosynthesis, but the reverse, photosynthesis when there is absorption, is not necessarily true. As a check on the existence of absorption limits we measured spectra for a few different leaves. Two techniques for measuring absorption have been used, viz. the separate determination of the diffuse reflectance and the diffuse transmittance with the leaf at a port of an integrating sphere and the direct determination of the non-absorbed fraction with the leaf in the sphere. In a cross-check both methods yielded the same results for the absorption spectrum. The spectrum of a Fuchsia leaf, covering the short-wave region from 350 to 2500 nm, shows a high absorption in UV, blue and red, the well known dip in the green and a steep fall-off at 700 nm. Absorption drops to virtually zero in the near infrared, with subsequent absorptions, corresponding to the water absorption bands. In more detailed spectra, taken at 5 nm intervals with a 5 nm bandwidth, differences in chlorophyll content show in the different depths of the dip around 550 nm and in a small shift of the absorption edge at 700 nm. Spectra for Geranium (Pelargonium zonale) and Hibiscus (with a higher chlorophyll content) show that the upper limit for photosynthesis can not be much above 700 nm. No evidence, however, is to be seen of a lower limit for photosynthesis and, in fact, some experiments down to 300 nm still did not show a decrease of the absorption although it is well recognized that no photosynthesis results with 300 nm wavelengths.

  17. Visible light broadband perfect absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Jia, X. L.; Meng, Q. X.; Yuan, C. X.; Zhou, Z. X.; Wang, X. O., E-mail: wxo@hit.edu.cn [School of Science, Harbin Institute of Technology, Harbin 150001 (China)

    2016-03-15

    The visible light broadband perfect absorbers based on the silver (Ag) nano elliptical disks and holes array are studied using finite difference time domain simulations. The semiconducting indium silicon dioxide thin film is introduced as the space layer in this sandwiched structure. Utilizing the asymmetrical geometry of the structures, polarization sensitivity for transverse electric wave (TE)/transverse magnetic wave (TM) and left circular polarization wave (LCP)/right circular polarization wave (RCP) of the broadband absorption are gained. The absorbers with Ag nano disks and holes array show several peaks absorbance of 100% by numerical simulation. These simple and flexible perfect absorbers are particularly desirable for various potential applications including the solar energy absorber.

  18. Performance of Closely Spaced Point Absorbers with Constrained Floater Motion

    DEFF Research Database (Denmark)

    De Backer, G.; Vantorre, M.; Beels, C.

    2009-01-01

    The performance of a wave energy converter array of twelve heaving point absorbers has been assessed numerically in a frequency domain model. Each point absorber is assumed to have its own linear power take-off. The impact of slamming, stroke and force restrictions on the power absorption...... is evaluated and optimal power take-off parameters are determined. For multiple bodies optimal control parameters are not only dependent on the incoming waves, but also on the position and behaviour of the other buoys. Applying the optimal control values for one buoy to multiple closely spaced buoys results...

  19. Energy providers: customer expectations

    International Nuclear Information System (INIS)

    Pridham, N.F.

    1997-01-01

    The deregulation of the gas and electric power industries, and how it will impact on customer service and pricing rates was discussed. This paper described the present situation, reviewed core competencies, and outlined future expectations. The bottom line is that major energy consumers are very conscious of energy costs and go to great lengths to keep them under control. At the same time, solutions proposed to reduce energy costs must benefit all classes of consumers, be they industrial, commercial, institutional or residential. Deregulation and competition at an accelerated pace is the most likely answer. This may be forced by external forces such as foreign energy providers who are eager to enter the Canadian energy market. It is also likely that the competition and convergence between gas and electricity is just the beginning, and may well be overshadowed by other deregulated industries as they determine their core competencies

  20. Power

    DEFF Research Database (Denmark)

    Elmholdt, Claus Westergård; Fogsgaard, Morten

    2016-01-01

    In this chapter, we will explore the dynamics of power in processes of creativity, and show its paradoxical nature as both a bridge and a barrier to creativity in organisations. Recent social psychological experimental research (Slighte, de Dreu & Nijstad, 2011) on the relation between power...... and floating source for empowering people in the organisation. We will explore and discuss here the potentials, challenges and pitfalls of power in relation to creativity in the life of organisations today. The aim is to demonstrate that power struggles may be utilised as constructive sources of creativity...

  1. Experiments with Point Absorber Type Wave Energy Converters in a Large-Scale Wave Basin

    DEFF Research Database (Denmark)

    Stratigaki, Vasiliki; Troch, Peter; Stallard, Tim

    2014-01-01

    Wave Energy Converters (WECs) extract energy from ocean waves and have the potential to produce a significant contribution of electricity from renewable sources. However, large "WEC farms" or "WEC arrays" are expected to have "WEC array effects", expressed as the impact of the WECs on the wave...... climate at an installation site, as well as on the overall power absorption of the WEC array. Experiments have been performed in the Shallow Water Wave Basin of DHI (Denmark) to study such "WEC array effects". Large arrays of up to 25 heaving point absorber type WECs have been tested for a range...... of geometric layout configurations and wave conditions. WEC response, wave induced forces on the WECs and wave field modifications have been measured. Each WEC consists of a buoy with diameter of 0.315 m. Power take-off is modeled by realizing friction based energy dissipation through damping of the WECs...

  2. Optical Pulsing in an Absorbing Liquid

    Science.gov (United States)

    Barnes, Jacob; Evans, Dean; Guha, Shekhar

    2003-03-01

    A continuous-wave laser can be converted into a series of repetitive pulses by focusing the laser beam into an absorbing liquid (e.g. nigrosine dissolved in a solvent), where the mechanism responsible for the pulses is the scattering of light off of photo-generated bubbles. The dependence of the pulsation frequency on the solvent, power, and cell thickness will be shown. The authors would like to acknowledge the contributions made by Prof. Daniel Lathrop (University of Maryland, Department of Physics) at the APS March 2002 meeting.

  3. Absorber materials in CANDU PHWR's

    International Nuclear Information System (INIS)

    Price, E.G.; Boss, C.R.; Novak, W.Z.; Fong, R.W.L.

    1995-03-01

    In a CANDU reactor the fuel channels are arranged on a square lattice in a calandria filled with heavy water moderator. This arrangement allows five types of tubular neutron absorber devices to be located in a relatively benign environment of low pressure, low temperature heavy water between neighbouring rows of columns of fuel channels. This paper will describe the roles of the devices and outline the design requirements of the absorber component from a reactor physics viewpoint. Nuclear heating and activation problems associated with the different absorbers will be briefly discussed. The design and manufacture of the devices will be also discussed. The control rod absorbers and shut off materials are cadmium and stainless steel. In the tubular arrangement, the cadmium is sandwiched between stainless steel tubes. This type of device has functioned well, but there is now concern over the availability and expense of cadmium which is used in two types of CANDU control devices. There are also concerns about the toxicity of cadmium during the fabrication of the absorbers. These concerns are prompting AECL to study alternatives. To minimize design changes, pure boron-10 alloyed in stainless steel is a favoured option. Work is underway to confirm the suitability of the boron-loaded steel and identify other encapsulated absorber materials for practical application. Because the reactivity devices or their guide tubes span the calandria vessel, the long slender components must be sufficiently rigid to resist operational vibration and also be seismically stable. Some of these components are made of Zircaloy to minimize neutron absorption. Slow irradiation growth and creep can reduce the spring tension, and periodic adjustments to the springs are required. Experience with the control absorber devices has generally been good. In one instance liquid zone controllers had a problem of vibration induced fretting but a designed back-fit resolved the problem. (author). 3 refs., 1

  4. Additive manufacturing of RF absorbers

    Science.gov (United States)

    Mills, Matthew S.

    The ability of additive manufacturing techniques to fabricate integrated electromagnetic absorbers tuned for specific radio frequency bands within structural composites allows for unique combinations of mechanical and electromagnetic properties. These composites and films can be used for RF shielding of sensitive electromagnetic components through in-plane and out-of-plane RF absorption. Structural composites are a common building block of many commercial platforms. These platforms may be placed in situations in which there is a need for embedded RF absorbing properties along with structural properties. Instead of adding radar absorbing treatments to the external surface of existing structures, which adds increased size, weight and cost; it could prove to be advantageous to integrate the microwave absorbing properties directly into the composite during the fabrication process. In this thesis, a method based on additive manufacturing techniques of composites structures with prescribed electromagnetic loss, within the frequency range 1 to 26GHz, is presented. This method utilizes screen printing and nScrypt micro dispensing to pattern a carbon based ink onto low loss substrates. The materials chosen for this study will be presented, and the fabrication technique that these materials went through to create RF absorbing structures will be described. The calibration methods used, the modeling of the RF structures, and the applications in which this technology can be utilized will also be presented.

  5. Wave energy extraction by coupled resonant absorbers.

    Science.gov (United States)

    Evans, D V; Porter, R

    2012-01-28

    In this article, a range of problems and theories will be introduced that will build towards a new wave energy converter (WEC) concept, with the acronym 'ROTA' standing for resonant over-topping absorber. First, classical results for wave power absorption for WECs constrained to operate in a single degree of freedom will be reviewed and the role of resonance in their operation highlighted. Emphasis will then be placed on how the introduction of further resonances can improve power take-off characteristics by extending the range of frequencies over which the efficiency is close to a theoretical maximum. Methods for doing this in different types of WECs will be demonstrated. Coupled resonant absorbers achieve this by connecting a WEC device equipped with its own resonance (determined from a hydrodynamic analysis) to a new system having separate mass/spring/damper characteristics. It is shown that a coupled resonant effect can be realized by inserting a water tank into a WEC, and this idea forms the basis of the ROTA device. In essence, the idea is to exploit the coupling between the natural sloshing frequencies of the water in the internal tank and the natural resonance of a submerged buoyant circular cylinder device that is tethered to the sea floor, allowing a rotary motion about its axis of attachment.

  6. Fuel with burnable absorber for RBMK-1500

    International Nuclear Information System (INIS)

    Krivosein, G.

    2002-01-01

    Following the accident at the Chernobyl Unit 4, the priority measures to improve RBMK's safety were developed. Under this program, the measures to reduce the void reactivity coefficient were executed on the stage-by-stage terms: As a result of these measures, the void reactivity coefficient was reduced below +1.0β. But there was decrease in fuel burnup to 14.0/14.5 MW.d/kg (design value ∼21/22 MW.d/kg). High power level of a fresh fuel assembly did not allow to employ fuel with higher enrichment without any compensatory measures. The different types of burnable absorbers were considered to be used. From the results of the anticipated calculations, it was specified that the most efficient power neutron flax flattening between fuel channels could be achieved when erbium was used. Ignalina NPP has used 2.4 % enriched fuel assemblies with burnable absorber since 1995. The fuel burnup has been increased by 60 %. The obtained experimental results are analyzed. (author)

  7. Water fugacity in absorbing polymers.

    Science.gov (United States)

    Burg, K J; Shalaby, S W

    1997-01-01

    Absorbable biomaterials, as dynamic systems, require special handling, processing, and characterization techniques beyond those of the traditional nonabsorbable materials. As the material degrades or absorbs, in vitro or in vivo, it undergoes structural, physical, and chemical changes. These changes in the base material may significantly impact the performance of a particular biomedical device; hence, it is important that the investigator consider the full range of properties that constitute the lifetime of a given absorbable material. The long term degradation study presented here sought to identify one such property, the change in water retention of a degrading oriented polylactide film. The investigation found through differential scanning calorimetry that later stages of degradation are often characterized by a stronger retention of water, potentially due to a higher number of polar carboxyl groups within the relatively hydrophobic polymer matrix.

  8. Essays on expectations, power and social security

    NARCIS (Netherlands)

    van der Wiel, K.M.

    2009-01-01

    In chapters four and five – ‘On Power’ – Karen analyzes data on household consumption, labor supply and wages. Chapter four proposes a non-cooperative, theoretical model on how couples jointly decide on what to buy and how much to work. Applying this model to what households in the U.S. Consumer

  9. Adaptive inertial shock-absorber

    International Nuclear Information System (INIS)

    Faraj, Rami; Holnicki-Szulc, Jan; Knap, Lech; Seńko, Jarosław

    2016-01-01

    This paper introduces and discusses a new concept of impact absorption by means of impact energy management and storage in dedicated rotating inertial discs. The effectiveness of the concept is demonstrated in a selected case-study involving spinning management, a recently developed novel impact-absorber. A specific control technique performed on this device is demonstrated to be the main source of significant improvement in the overall efficiency of impact damping process. The influence of various parameters on the performance of the shock-absorber is investigated. Design and manufacturing challenges and directions of further research are formulated. (paper)

  10. Best Practice Life Expectancy

    DEFF Research Database (Denmark)

    Medford, Anthony

    2017-01-01

    probability estimates of best-practice life expectancy levels or make projections about future maximum life expectancy. Comments: Our findings may be useful for policymakers and insurance/pension analysts who would like to obtain estimates and probabilities of future maximum life expectancies.......Background: Whereas the rise in human life expectancy has been extensively studied, the evolution of maximum life expectancies, i.e., the rise in best-practice life expectancy in a group of populations, has not been examined to the same extent. The linear rise in best-practice life expectancy has...... been reported previously by various authors. Though remarkable, this is simply an empirical observation. Objective: We examine best-practice life expectancy more formally by using extreme value theory. Methods: Extreme value distributions are fit to the time series (1900 to 2012) of maximum life...

  11. Absorbing-and-diffusing coating

    OpenAIRE

    Tkalich, N. V.; Mokeev, Yu. G.; Onipko, A. F.; Vashchenko, V. F.; Topchev, M. D.; Glebov, V. V.; Ivanchenko, Dmitrij D.; Kolchigin, Nikolay N.; Yevdokimov, V. V.

    2003-01-01

    The paper presents the results of complex experimental research of the absorbing-and-diffusing material "Contrast". It is shown to be an efficient wideband-camouflage material in the radiolocation and the video bands. Ways for improving the material characteristics are outlined.

  12. Selective solar absorber emittance measurement at elevated temperature

    Science.gov (United States)

    Giraud, Philémon; Braillon, Julien; Raccurt, Olivier

    2017-06-01

    Durability of solar components for CSP (Concentrated Solar Power Plant) technologies is a key point to lower cost and ensure their large deployment. These technologies concentrated the solar radiation by means of mirrors on a receiver tube where it is collected as thermal energy. The absorbers are submitted to strong environmental constraints and the degradation of their optical properties (emittance and solar absorbance) have a direct impact on performance. The characterization of a material in such condition is complicated and requires advanced apparatuses, and different measurement methods exist for the determination of the two quantities of relevance regarding an absorber, which are its emittance and its solar absorbance. The objective is to develop new optical equipment for measure the emittance of this solar absorber at elevated temperature. In this paper, we present an optical bench developed for emittance measurement on absorbers is conditions of use. Results will be shown, with a discussion of some factors of influence over this measurement and how to control them.

  13. ASSESSMENT OF BURNABLE ABSORBER FUEL DESIGN BY UWB1 DEPLETION CODE

    Directory of Open Access Journals (Sweden)

    Martin Lovecky

    2016-12-01

    Full Text Available UWB1 depletion code is being developed as a fast computational tool for the study of burnable absorbers in University of West Bohemia in Pilsen, Czech Republic. Research of fuel depletion aims at development and introduction of advanced types of burnable absorbers in nuclear fuel. Burnable absorbers compensate for the initial excess reactivity and consequently allow for lower power peaking factors and longer fuel cycles with higher fuel enrichments. The paper describes the depletion calculations of CANDU, PWR and SFR nuclear fuel doped with rare earth oxides as burnable absorber. Uniform distribution of burnable absorber in the fuel is assumed. Based on performed depletion calculations, rare earth oxides are divided into two groups, suitable burnable absorbers and poisoning absorbers. Moreover, basic economic comparison is performed based on actual stock prices.

  14. Radiation sterilization of absorbent cotton and of absorbent gauze

    International Nuclear Information System (INIS)

    Hosobuchi, Kazunari; Oka, Mitsuru; Kaneko, Akira; Ishiwata, Hiroshi.

    1986-01-01

    The bioburden of absorbent cotton and of absorbent gauze and their physical and chemical characteristics after irradiation are investigated. The survey conducted on contaminants of 1890 cotton samples from 53 lots and 805 gauze samples from 56 lots showed maximum numbers of microbes per g of the cotton and gauze were 859 (an average of 21.4) and 777 (an average of 42.2), respectively. Isolation and microbiological and biochemical tests of representative microbes indicated that all of them, except one, were bacilli. The sterilization dose at 10 -6 of sterlity assurance level was found to be 2.0 Mrad when irradiated the spores loaded on paper strips and examined populations having graded D values from 0.10 to 0.28 Mrad. The sterilization dose would be about 1.5 Mrad if subjected the average numbers of contaminants observed in this study to irradiation. No significant differences were found between the irradiated samples and control up to 2 Mrad in tensile strength, change of color, absorbency, sedimentation rate, soluble substances, and pH of solutions used for immersion and other tests conventionally used. These results indicate that these products can be sterilized by irradiation. (author)

  15. Cross connecting absorber module inlets of multiple boiler units

    International Nuclear Information System (INIS)

    Cirillo, A.J.; Sperber, P.K.; Belavadi, V.N.; Mukherji, A.

    1991-01-01

    The retrofitting of scrubbers downstream of existing balanced draft boilers is often accomplished by the addition of induced draft (ID) booster fans. By creating a common plenum between the ID fans and the ID booster fans of two or more boiler-absorber trains, absorber module capacity may be shared among multiple boiler units. At Harrison Power Station, three (3) 4,900,000 lb/hour boilers (640 MWe Gross) will be linked through a common plenum. This sharing capability precludes the need to add standby module capacity, thereby saving capital dollars and keeping project critical path schedules, which typically run through absorber procurement and construction, to a minimum. Through damper placement in the ductwork cross connections, unitized boiler-absorber module operation or common plenum operation may be obtained, thus providing both operational flexibility and reliability. Additionally, open plenum operation allows the removal of an absorber unit from service, while keeping its associated boiler on line, thereby precluding 'cold starts' and maintaining overall unit availabilities. As either unitized or common plenum operation is possible with the cross connection, the furnace draft control systems of each boiler must be examined for varying load operation and trip conditions. This paper addresses the means by which to analyze such cross connection operational scenarios while maintaining compliance with furnace flame out safety guidelines, and will discuss the physical design considerations, ramifications and benefits of same, with select emphasis on what is being implemented at the Harrison Power Station

  16. Determining health expectancies

    National Research Council Canada - National Science Library

    Robine, Jean-Marie

    2003-01-01

    ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Jean-Marie Robine 9 1 Increase in Life Expectancy and Concentration of Ages at Death . . . . France Mesle´ and Jacques Vallin 13 2 Compression of Morbidity...

  17. Humans expect generosity

    Science.gov (United States)

    Brañas-Garza, Pablo; Rodríguez-Lara, Ismael; Sánchez, Angel

    2017-02-01

    Mechanisms supporting human ultra-cooperativeness are very much subject to debate. One psychological feature likely to be relevant is the formation of expectations, particularly about receiving cooperative or generous behavior from others. Without such expectations, social life will be seriously impeded and, in turn, expectations leading to satisfactory interactions can become norms and institutionalize cooperation. In this paper, we assess people’s expectations of generosity in a series of controlled experiments using the dictator game. Despite differences in respective roles, involvement in the game, degree of social distance or variation of stakes, the results are conclusive: subjects seldom predict that dictators will behave selfishly (by choosing the Nash equilibrium action, namely giving nothing). The majority of subjects expect that dictators will choose the equal split. This implies that generous behavior is not only observed in the lab, but also expected by subjects. In addition, expectations are accurate, matching closely the donations observed and showing that as a society we have a good grasp of how we interact. Finally, correlation between expectations and actual behavior suggests that expectations can be an important ingredient of generous or cooperative behavior.

  18. Synthesis and microwave absorbing properties of Cobalt ferrite

    Science.gov (United States)

    Liu, H. Y.; Li, Y. S.

    2018-01-01

    Cobalt ferrite power CoFe2O4 was synthesized through the chemical co-precipitation method. The structure, morphology and microwave absorbing properties were studied by changing raw materials, annealing temperature and experimental steps. The measurements of X-ray diffraction and scanning electron micrograph suggest that annealed CoFe2O4 sample is still a spinel structure. Moreover, the crystalline and grain sizes become large with the enhancement of annealing temperature. The measurements of microwave absorbing properties show that the reflection loss decreases continuously, and the wavelength of maximum absorption loss shift to short-wave limit as the sample thickness increases.

  19. Performance appraisal of expectations

    Directory of Open Access Journals (Sweden)

    Russkikh G.A.

    2016-11-01

    Full Text Available this article provides basic concepts for teachers to estimate and reach planned students’ expectations, describes functions and elements of expectations; nature of external and internal estimate, technology to estimate the results, gives recommendations how to create diagnostic assignments.

  20. Marijuana: College Students' Expectations.

    Science.gov (United States)

    Rumstein, Regina

    1980-01-01

    Focused on college students' expectations about marijuana. Undergraduates (N=210) expected marijuana to have sedating effects; they largely discounted psychological consequences. Students considered marijuana to be an educational issue and favored decriminalization of the drug. Users, occasional users, and nonusers differed significantly in…

  1. Query complexity in expectation

    NARCIS (Netherlands)

    Kaniewski, J.; Lee, T.; de Wolf, R.; Halldórsson, M.M.; Iwama, K.; Kobayashi, N.; Speckmann, B.

    2015-01-01

    We study the query complexity of computing a function f:{0,1}n→R+ in expectation. This requires the algorithm on input x to output a nonnegative random variable whose expectation equals f(x), using as few queries to the input x as possible. We exactly characterize both the randomized and the quantum

  2. Life Expectancy in 2040

    DEFF Research Database (Denmark)

    Canudas-Romo, Vladimir; DuGoff, Eva H; Wu, Albert W.

    2016-01-01

    expectancy at age 20 will increase by approximately one year per decade for females and males between now and 2040. According to the clinical experts, 70% of the improvement in life expectancy will occur in cardiovascular disease and cancer, while in the last 30 years most of the improvement has occurred...

  3. Plasmonic titanium nitride nanostructures for perfect absorbers

    DEFF Research Database (Denmark)

    Guler, Urcan; Li, Wen-Wei; Kinsey, Nathaniel

    2013-01-01

    We propose a metamaterial based perfect absorber in the visible region, and investigate the performance of titanium nitride as an alternative plasmonic material. Numerical and experimental results reveal that titanium nitride performs better than gold as a plasmonic absorbing material...

  4. Integration of regenerative shock absorber into vehicle electric system

    Science.gov (United States)

    Zhang, Chongxiao; Li, Peng; Xing, Shaoxu; Kim, Junyoung; Yu, Liangyao; Zuo, Lei

    2014-03-01

    Regenerative/Energy harvesting shock absorbers have a great potential to increase fuel efficiency and provide suspension damping simultaneously. In recent years there's intensive work on this topic, but most researches focus on electricity extraction from vibration and harvesting efficiency improvement. The integration of electricity generated from regenerative shock absorbers into vehicle electric system, which is very important to realize the fuel efficiency benefit, has not been investigated. This paper is to study and demonstrate the integration of regenerative shock absorber with vehicle alternator, battery and in-vehicle electrical load together. In the presented system, the shock absorber is excited by a shaker and it converts kinetic energy into electricity. The harvested electricity flows into a DC/DC converter which realizes two functions: controlling the shock absorber's damping and regulating the output voltage. The damping is tuned by controlling shock absorber's output current, which is also the input current of DC/DC converter. By adjusting the duty cycles of switches in the converter, its input impedance together with input current can be adjusted according to dynamic damping requirements. An automotive lead-acid battery is charged by the DC/DC converter's output. To simulate the working condition of combustion engine, an AC motor is used to drive a truck alternator, which also charges the battery. Power resistors are used as battery's electrical load to simulate in-vehicle electrical devices. Experimental results show that the proposed integration strategy can effectively utilize the harvested electricity and power consumption of the AC motor is decreased accordingly. This proves the combustion engine's load reduction and fuel efficiency improvement.

  5. Piezooptic effect of absorbing environment

    Directory of Open Access Journals (Sweden)

    Ю. А. Рудяк

    2013-07-01

    Full Text Available Application of piezooptic effect of absorbing environment for the definition of the parameter of stress deformation state was examined. The analysis of dielectric permeability tensor of imaginary parts was done. It is shown that changes in the real part dielectric permeability tensor mainly the indicator of fracture was fixed by means of mechanics interference methods and the changes in the imaginary part (α – real rate of absorption can be measured by means of analysis of light absorption and thus stress deformation state can be determined

  6. Absorber modeling for NGCC carbon capture with aqueous piperazine.

    Science.gov (United States)

    Zhang, Yue; Freeman, Brice; Hao, Pingjiao; Rochelle, Gary T

    2016-10-20

    A hybrid system combining amine scrubbing with membrane technology for carbon capture from natural gas combined cycle (NGCC) power plants is proposed in this paper. In this process, the CO 2 in the flue gas can be enriched from 4% to 18% by the membrane, and the amine scrubbing system will have lower capture costs. Aqueous piperazine (PZ) is chosen as the solvent. Different direct contact cooler (DCC) options, multiple absorber operating conditions, optimal intercooling designs, and different cooling options have been evaluated across a wide range of inlet CO 2 . Amine scrubbing without DCC is a superior design for NGCC carbon capture. Pump-around cooling at the bottom of the absorber can effectively manage the temperature of the hot flue gas, and still be effective for CO 2 absorption. The absorber gas inlet must be designed to avoid excessive localized temperature and solvent evaporation. When the inlet CO 2 increases from 4% to 18%, total absorber CAPEX decreases by 60%; another 10% of the total absorber CAPEX can be saved by eliminating the DCC. In-and-out intercooling works well for high CO 2 , while pump-around intercooling is more effective for low CO 2 . Dry cooling requires more packing and energy but appears to be technically and economically feasible if cooling water availability is limited.

  7. Colorful solar selective absorber integrated with different colored units.

    Science.gov (United States)

    Chen, Feiliang; Wang, Shao-Wei; Liu, Xingxing; Ji, Ruonan; Li, Zhifeng; Chen, Xiaoshuang; Chen, Yuwei; Lu, Wei

    2016-01-25

    Solar selective absorbers are the core part for solar thermal technologies such as solar water heaters, concentrated solar power, solar thermoelectric generators and solar thermophotovoltaics. Colorful solar selective absorber can provide new freedom and flexibility beyond energy performance, which will lead to wider utilization of solar technologies. In this work, we present a monolithic integration of colored solar absorber array with different colors on a single substrate based on a multilayered structure of Cu/TiN(x)O(y)/TiO(2)/Si(3)N(4)/SiO(2). A colored solar absorber array with 16 color units is demonstrated experimentally by using combinatorial deposition technique via changing the thickness of SiO(2) layer. The solar absorptivity and thermal emissivity of all the color units is higher than 92% and lower than 5.5%, respectively. The colored solar selective absorber array can have colorful appearance and designable patterns while keeping high energy performance at the same time. It is a new candidate for a number of solar applications, especially for architecture integration and military camouflage.

  8. Expect Respect: Healthy Relationships

    Science.gov (United States)

    ... Listen Español Text Size Email Print Share Expect Respect: Healthy Relationships Page Content Article Body Signs of ... good about what happens when they are together. Respect You ask each other what you want to ...

  9. Multi-channel coherent perfect absorbers

    KAUST Repository

    Bai, Ping

    2016-05-18

    The absorption efficiency of a coherent perfect absorber usually depends on the phase coherence of the incident waves on the surfaces. Here, we present a scheme to create a multi-channel coherent perfect absorber in which the constraint of phase coherence is loosened. The scheme has a multi-layer structure such that incident waves in different channels with different angular momenta can be simultaneously and perfectly absorbed. This absorber is robust in achieving high absorption efficiency even if the incident waves become "incoherent" and possess "random" wave fronts. Our work demonstrates a unique approach to designing highly efficient metamaterial absorbers. © CopyrightEPLA, 2016.

  10. Graphene based salisbury screen for terahertz absorber

    Science.gov (United States)

    Min Woo, Jeong; Kim, Min-Sik; Woong Kim, Hyun; Jang, Jae-Hyung

    2014-02-01

    A graphene-based, multiband absorber operating in terahertz (THz) frequency range was demonstrated. Graphene film was transferred onto the top of a flexible polymer substrate backed with a gold reflector. The graphene acts as a resistive film that partially attenuates and reflects THz waves. The destructive interference between THz waves reflected from graphene and backside reflector gives rise to perfect absorbance at multiple frequencies. To enhance the absorbance on/off ratio (AR), the conductivity of graphene was varied using a chemical doping method. The resulting p-doped, graphene-based THz absorber exhibited absorbance at maxima and AR higher than 0.95 and 25 dB, respectively.

  11. Spiking the expectancy profiles

    DEFF Research Database (Denmark)

    Hansen, Niels Chr.; Loui, Psyche; Vuust, Peter

    Melodic expectations are generated with different degrees of certainty. Given distributions of expectedness ratings for multiple continuations of each context, as obtained with the probe-tone paradigm, this certainty can be quantified in terms of Shannon entropy. Because expectations arise from...... statistical learning, causing comparatively sharper key profiles in musicians, we hypothesised that musical learning can be modelled as a process of entropy reduction through experience. Specifically, implicit learning of statistical regularities allows reduction in the relative entropy (i.e. symmetrised...... Kullback-Leibler or Jensen-Shannon Divergence) between listeners’ prior expectancy profiles and probability distributions of a musical style or of stimuli used in short-term experiments. Five previous probe-tone experiments with musicians and non-musicians were revisited. In Experiments 1-2 participants...

  12. Performance expectation plan

    Energy Technology Data Exchange (ETDEWEB)

    Ray, P.E.

    1998-09-04

    This document outlines the significant accomplishments of fiscal year 1998 for the Tank Waste Remediation System (TWRS) Project Hanford Management Contract (PHMC) team. Opportunities for improvement to better meet some performance expectations have been identified. The PHMC has performed at an excellent level in administration of leadership, planning, and technical direction. The contractor has met and made notable improvement of attaining customer satisfaction in mission execution. This document includes the team`s recommendation that the PHMC TWRS Performance Expectation Plan evaluation rating for fiscal year 1998 be an Excellent.

  13. The Qualitative Expectations Hypothesis

    DEFF Research Database (Denmark)

    Frydman, Roman; Johansen, Søren; Rahbek, Anders

    2017-01-01

    We introduce the Qualitative Expectations Hypothesis (QEH) as a new approach to modeling macroeconomic and financial outcomes. Building on John Muth's seminal insight underpinning the Rational Expectations Hypothesis (REH), QEH represents the market's forecasts to be consistent with the predictions...... of an economistís model. However, by assuming that outcomes lie within stochastic intervals, QEH, unlike REH, recognizes the ambiguity faced by an economist and market participants alike. Moreover, QEH leaves the model open to ambiguity by not specifying a mechanism determining specific values that outcomes take...

  14. The Qualitative Expectations Hypothesis

    DEFF Research Database (Denmark)

    Frydman, Roman; Johansen, Søren; Rahbek, Anders

    We introduce the Qualitative Expectations Hypothesis (QEH) as a new approach to modeling macroeconomic and financial outcomes. Building on John Muth's seminal insight underpinning the Rational Expectations Hypothesis (REH), QEH represents the market's forecasts to be consistent with the predictions...... of an economist's model. However, by assuming that outcomes lie within stochastic intervals, QEH, unlike REH, recognizes the ambiguity faced by an economist and market participants alike. Moreover, QEH leaves the model open to ambiguity by not specifying a mechanism determining specific values that outcomes take...

  15. Numerical Modeling of a Wave Energy Point Absorber

    DEFF Research Database (Denmark)

    Hernandez, Lorenzo Banos; Frigaard, Peter; Kirkegaard, Poul Henning

    2009-01-01

    The present study deals with numerical modelling of the Wave Star Energy WSE device. Hereby, linear potential theory is applied via a BEM code on the wave hydrodynamics exciting the floaters. Time and frequency domain solutions of the floater response are determined for regular and irregular seas....... Furthermore, these results are used to estimate the power and the energy absorbed by a single oscillating floater. Finally, a latching control strategy is analysed in open-loop configuration for energy maximization....

  16. Expected Term Structures

    DEFF Research Database (Denmark)

    Buraschi, Andrea; Piatti, Ilaria; Whelan, Paul

    This paper studies the properties of bond risk premia in the cross-section of subjective expectations. We exploit an extensive dataset of yield curve forecasts from financial institutions and document a number of novel findings. First, contrary to evidence presented for stock markets but consiste...... of heterogeneous beliefs is taken into account....

  17. Great Expectations. [Lesson Plan].

    Science.gov (United States)

    Devine, Kelley

    Based on Charles Dickens' novel "Great Expectations," this lesson plan presents activities designed to help students understand the differences between totalitarianism and democracy; and a that a writer of a story considers theme, plot, characters, setting, and point of view. The main activity of the lesson involves students working in groups to…

  18. Parenting with High Expectations

    Science.gov (United States)

    Timperlake, Benna Hull; Sanders, Genelle Timperlake

    2014-01-01

    In some ways raising deaf or hard of hearing children is no different than raising hearing children; expectations must be established and periodically tweaked. Benna Hull Timperlake, who with husband Roger, raised two hearing children in addition to their deaf daughter, Genelle Timperlake Sanders, and Genelle, now a deaf professional, share their…

  19. Magnetic field effects on microwave absorbing materials

    Science.gov (United States)

    Goldberg, Ira; Hollingsworth, Charles S.; Mckinney, Ted M.

    1991-01-01

    The objective of this program was to gather information to formulate a microwave absorber that can work in the presence of strong constant direct current (DC) magnetic fields. The program was conducted in four steps. The first step was to investigate the electrical and magnetic properties of magnetic and ferrite microwave absorbers in the presence of strong magnetic fields. This included both experimental measurements and a literature survey of properties that may be applicable to finding an appropriate absorbing material. The second step was to identify those material properties that will produce desirable absorptive properties in the presence of intense magnetic fields and determine the range of magnetic field in which the absorbers remain effective. The third step was to establish ferrite absorber designs that will produce low reflection and adequate absorption in the presence of intense inhomogeneous static magnetic fields. The fourth and final step was to prepare and test samples of such magnetic microwave absorbers if such designs seem practical.

  20. Comments on liquid hydrogen absorbers for MICE

    International Nuclear Information System (INIS)

    Green, Michael A.

    2003-01-01

    This report describes the heat transfer problems associated with a liquid hydrogen absorber for the MICE experiment. This report describes a technique for modeling heat transfer from the outside world, to the absorber case and in its vacuum vessel, to the hydrogen and then into helium gas at 14 K. Also presented are the equation for free convection cooling of the liquid hydrogen in the absorber

  1. Multiband Negative Permittivity Metamaterials and Absorbers

    Directory of Open Access Journals (Sweden)

    Yiran Tian

    2013-01-01

    Full Text Available Design and characteristics of multiband negative permittivity metamaterial and its absorber configuration are presented in this paper. The proposed multiband metamaterial is composed of a novel multibranch resonator which can possess four electric resonance frequencies. It is shown that, by controlling the length of the main branches of such resonator, the resonant frequencies and corresponding absorbing bands of metamaterial absorber can be shifted in a large frequency band.

  2. Chinese students' great expectations

    DEFF Research Database (Denmark)

    Thøgersen, Stig

    2013-01-01

    The article focuses on Chinese students' hopes and expectations before leaving to study abroad. The national political environment for their decision to go abroad is shaped by an official narrative of China's transition to a more creative and innovative economy. Students draw on this narrative to...... system, they think of themselves as having a role in the transformation of Chinese attitudes to education and parent-child relations.......The article focuses on Chinese students' hopes and expectations before leaving to study abroad. The national political environment for their decision to go abroad is shaped by an official narrative of China's transition to a more creative and innovative economy. Students draw on this narrative...

  3. Spiking the expectancy profiles

    DEFF Research Database (Denmark)

    Hansen, Niels Chr.; Loui, Psyche; Vuust, Peter

    Melodic expectations have long been quantified using expectedness ratings. Motivated by statistical learning and sharper key profiles in musicians, we model musical learning as a process of reducing the relative entropy between listeners' prior expectancy profiles and probability distributions...... of a given musical style or of stimuli used in short-term experiments. Five previous probe-tone experiments with musicians and non-musicians are revisited. Exp. 1-2 used jazz, classical and hymn melodies. Exp. 3-5 collected ratings before and after exposure to 5, 15 or 400 novel melodies generated from...... a finite-state grammar using the Bohlen-Pierce scale. We find group differences in entropy corresponding to degree and relevance of musical training and within-participant decreases after short-term exposure. Thus, whereas inexperienced listeners make high-entropy predictions by default, statistical...

  4. Life expectancy and education

    DEFF Research Database (Denmark)

    Hansen, Casper Worm; Strulik, Holger

    2017-01-01

    This paper exploits the unexpected decline in the death rate from cardiovascular diseases since the 1970s as a large positive health shock that affected predominantly old-age mortality; i.e. the fourth stage of the epidemiological transition. Using a difference-in-differences estimation strategy......, we find that US states with higher mortality rates from cardiovascular disease prior to the 1970s experienced greater increases in adult life expectancy and higher education enrollment. Our estimates suggest that a one-standard deviation higher treatment intensity is associated with an increase...... in adult life expectancy of 0.37 years and 0.07–0.15 more years of higher education....

  5. Generalized pin factor methodology for LWR reload cores with discrete burnable absorbers

    International Nuclear Information System (INIS)

    Hah, C.J.; Hideki Matsumoto; Toshikazu Ida; Lee, C.; Chao, Y.A.

    2005-01-01

    Discrete burnable absorbers are used to suppress excess reactivity as well as peak pin power in an assembly. After the burn-out of absorption material, discrete burnable absorbers are usually removed from assembly guide tubes for the next cycle. For that case, the pin factors with discrete burnable absorbers cannot be used since the assembly configuration is physically changed. The pin factors without discrete burnable absorbers also have noticeable deviation from the actual case because they do not take into account the history effect due to the residence of discrete burnable absorbers for the previous cycle. In this paper, the generalized pin factor (GPF) method is developed to accurately predict pin powers by considering the history effect. The method uses a second-order polynomial function to approximate the history effect which builds up during the residence of burnable absorber material and employs a linear approximation to simulate the decay of the history effect after discrete burnable absorbers are removed. The verification results from Westinghouse Vantage- 5H assemblies with WABAs showed that pin power errors were significantly reduced by using the GPF. (authors)

  6. Reputation and Rational Expectations

    OpenAIRE

    Andersen, Torben; Risager, Ole

    1987-01-01

    The paper considers the importance of reputation in relation to disinflationary policies in a continuous time ration expectations model, where the private sector has incomplete information about the true preferences of the government. It is proved that there is a unique equilibrium with the important property that the costs of disinflation arise in the start of the game where the policy has not yet gained credibility. Published in connection with a visit at the IIES.

  7. Device for absorbing mechanical shock

    Science.gov (United States)

    Newlon, C.E.

    1979-08-29

    This invention is a comparatively inexpensive but efficient shock-absorbing device having special application to the protection of shipping and storage cylinders. In a typical application, two of the devices are strapped to a cylinder to serve as saddle-type supports for the cylinder during storage and to protect the cylinder in the event it is dropped during lifting or lowering operations. In its preferred form, the invention includes a hardwood plank whose grain runs in the longitudinal direction. The basal portion of the plank is of solid cross-section, whereas the upper face of the plank is cut away to form a concave surface fittable against the sidewall of a storage cylinder. The concave surface is divided into a series of segments by transversely extending, throughgoing relief slots. A layer of elastomeric material is positioned on the concave face, the elastomer being extrudable into slots when pressed against the segments by a preselected pressure characteristic of a high-energy impact. The compressive, tensile, and shear properties of the hardwood and the elastomer are utilized in combination to provide a surprisingly high energy-absorption capability.

  8. Gaseous carbon dioxide absorbing column

    International Nuclear Information System (INIS)

    Harashina, Heihachi.

    1994-01-01

    The absorbing column of the present invention comprises a cyclone to which CO 2 gas and Ca(OH) 2 are blown to form CaCO 3 , a water supply means connected to an upper portion of the cyclone for forming a thin water membrane on the inner wall thereof, and a water processing means connected to a lower portion of the cyclone for draining water incorporating CaCO 3 . If a mixed fluid of CO 2 gas and Ca(OH) 2 is blown in a state where a flowing water membrane is formed on the inner wall of the cyclone, formation of CaCO 3 is promoted also in the inside of the cyclone in addition to the formation of CaCO 3 in the course of blowing. Then, formed CaCO 3 is discharged from the lower portion of the cyclone together with downwardly flowing water. With such procedures, solid contents such as CaCO 3 separated at the inner circumferential wall are sent into the thin water membrane, adsorbed and captured, and the solid contents are successively washed out, so that a phenomenon that the solid contents deposit and grow on the inner wall of the cyclone can be prevented effectively. (T.M.)

  9. Benchmark solution of contemporary PWR integral fuel burnable absorbers

    International Nuclear Information System (INIS)

    Stucker, D.L.; Hone, M.J.; Holland, R.A.

    1993-01-01

    This paper presents a closely controlled benchmark solution of the two major contemporary pressurized water reactor integral burnable absorber designs: zirconium diboride (ZrB 2 ) and gadolinia (Gd 2 O 3 ). The comparison is accomplished using self-generating equilibrium cycles with equal energy, equal discharge burnup, and equal safety constraints. The reference plant for this evaluation is a 3411-MW(thermal) Westinghouse four-loop nuclear steam supply system operating with an inlet temperature of 285.9 degrees C, a core coolant mass now rate of 16877.3 kg/s, and coolant pressure of 15.5 MPa. The reactor consists of 193 VANTAGE 5H fuel assemblies that are discharged at a region average burnup of 48.4 GWd/tonne U. Each fuel assembly contains a natural uranium axial blanket 15.24 cm long at the top and the bottom of the fuel rod. The burnable absorber rods are symmetrically radially dispersed within the fuel assembly such that intrabundle power peaking is minimized. The burnable absorber material for both ZrB 2 and Gd 2 O 3 is axially zoned to the central 304.8 cm of the absorber-bearing fuel rods. The fuel management was constrained such that the thermal and safety limitations of F δH q -5 /degrees C were simultaneously achieved. The maximum long-term operating soluble boron concentration was also limited to 446 effective full-power days (EFPDs) including 14 EFPDs of power coastdown were assumed

  10. On the Optimization of Point Absorber Buoys

    Directory of Open Access Journals (Sweden)

    Linnea Sjökvist

    2014-05-01

    Full Text Available A point absorbing wave energy converter (WEC is a complicated dynamical system. A semi-submerged buoy drives a power take-off device (PTO, which acts as a linear or non-linear damper of the WEC system. The buoy motion depends on the buoy geometry and dimensions, the mass of the moving parts of the system and on the damping force from the generator. The electromagnetic damping in the generator depends on both the generator specifications, the connected load and the buoy velocity. In this paper a velocity ratio has been used to study how the geometric parameters buoy draft and radius, assuming constant generator damping coefficient, affects the motion and the energy absorption of a WEC. It have been concluded that an optimal buoy geometry can be identified for a specific generator damping. The simulated WEC performance have been compared with experimental values from two WECs with similar generators but different buoys. Conclusions have been drawn about their behaviour.

  11. Quasar 2175 Å dust absorbers - I. Metallicity, depletion pattern and kinematics

    Science.gov (United States)

    Ma, Jingzhe; Ge, Jian; Zhao, Yinan; Prochaska, J. Xavier; Zhang, Shaohua; Ji, Tuo; Schneider, Donald P.

    2017-12-01

    We present 13 new 2175 Å dust absorbers at zabs = 1.0-2.2 towards background quasars from the Sloan Digital Sky Survey. These absorbers are examined in detail using data from the Echelle Spectrograph and Imager (ESI) on the Keck II telescope. Many low-ionization lines including Fe II, Zn II, Mg II, Si II, Al II, Ni II, Mn II, Cr II, Ti II and Ca II are present in the same absorber that gives rise to the 2175 Å bump. The relative metal abundances (with respect to Zn) demonstrate that the depletion patterns of our 2175 Å dust absorbers resemble that of the Milky Way clouds although some are disc-like and some are halo-like. The 2175 Å dust absorbers have significantly higher depletion levels compared to literature damped Lyman α absorbers (DLAs) and sub-DLAs. The dust depletion level indicator [Fe/Zn] tends to anticorrelate with bump strengths. The velocity profiles from the Keck/ESI spectra also provide kinematical information on the dust absorbers. The dust absorbers are found to have multiple velocity components with velocity widths extending from ∼100 to ∼600 km s-1, which are larger than those of most DLAs and sub-DLAs. Assuming the velocity width is a reliable tracer of stellar mass, the host galaxies of 2175 Å dust absorbers are expected to be more massive than DLA/sub-DLA hosts. Not all of the 2175 Å dust absorbers are intervening systems towards background quasars. The absorbers towards quasars J1006+1538 and J1047+3423 are proximate systems that could be associated with the quasar itself or the host galaxy.

  12. Photoluminescence-based quality control for thin film absorber layers of photovoltaic devices

    Science.gov (United States)

    Repins, Ingrid L.; Kuciauskas, Darius

    2015-07-07

    A time-resolved photoluminescence-based system providing quality control during manufacture of thin film absorber layers for photovoltaic devices. The system includes a laser generating excitation beams and an optical fiber with an end used both for directing each excitation beam onto a thin film absorber layer and for collecting photoluminescence from the absorber layer. The system includes a processor determining a quality control parameter such as minority carrier lifetime of the thin film absorber layer based on the collected photoluminescence. In some implementations, the laser is a low power, pulsed diode laser having photon energy at least great enough to excite electron hole pairs in the thin film absorber layer. The scattered light may be filterable from the collected photoluminescence, and the system may include a dichroic beam splitter and a filter that transmit the photoluminescence and remove scattered laser light prior to delivery to a photodetector and a digital oscilloscope.

  13. Intrascleral outflow after deep sclerectomy with absorbable and non-absorbable implants in the rabbit eye

    OpenAIRE

    Ka?u?ny, Jakub J.; Grzanka, Dariusz; Wi?niewska, Halina; Niewi?ska, Alicja; Ka?u?ny, Bart?omiej J.; Grzanka, Alina

    2012-01-01

    Summary Background The purpose of the study is an analysis of intrascleral drainage vessels formed in rabbits? eyes after non-penetrating deep sclerectomy (NPDS) with absorbable and non-absorbable implants, and comparison to eyes in which surgery was performed without implanted material. Material/Methods NPDS was carried out in 12 rabbits, with implantation of non-absorbable methacrylic hydrogel (N=10 eyes) or absorbable cross-linked sodium hyaluronate (N=6 eyes), or without any implant (N=8 ...

  14. Absorbencies of six different rodent beddings: commercially advertised absorbencies are potentially misleading.

    Science.gov (United States)

    Burn, C C; Mason, G J

    2005-01-01

    Moisture absorbency is one of the most important characteristics of rodent beddings for controlling bacterial growth and ammonia production. However, bedding manufacturers rarely provide information on the absorbencies of available materials, and even when they do, absorption values are usually expressed per unit mass of bedding. Since beddings are usually placed into cages to reach a required depth rather than a particular mass, their volumetric absorbencies are far more relevant. This study therefore compared the saline absorbencies of sawdust, aspen woodchips, two virgin loose pulp beddings (Alpha-Dri and Omega-Dri), reclaimed wood pulp (Tek-Fresh), and corncob, calculated both by volume and by mass. Absorbency per unit volume correlated positively with bedding density, while absorbency per unit mass correlated negatively. Therefore, the relative absorbencies of the beddings were almost completely reversed depending on how absorbency was calculated. By volume, corncob was the most absorbent bedding, absorbing about twice as much saline as Tek-Fresh, the least absorbent bedding. Conversely, when calculated by mass, Tek-Fresh appeared to absorb almost three times as much saline as the corncob. Thus, in practical terms the most absorbent bedding here was corncob, followed by the loose pulp beddings; and this is generally supported by their relatively low ammonia production as seen in previous studies. Many factors other than absorbency determine whether a material is suitable as a rodent bedding, and they are briefly mentioned here. However, manufacturers should provide details of bedding absorbencies in terms of volume, in order to help predict the relative absorbencies of the beddings in practical situations.

  15. Absorbed radiation dose on LHC interconnects

    CERN Document Server

    Versaci, R; Vlachoudis, V; CERN. Geneva. ATS Department

    2011-01-01

    Here we present the results of our FLUKA simulations devoted to the evaluation of the peak dose absorbed by the busbar insulator in the LHC Interaction Region 7 interconnects. The peak dose absorbed by the cold magnet coils are also presented.

  16. Comments on liquid hydrogen absorbers for MICE

    Energy Technology Data Exchange (ETDEWEB)

    Green, Michael A.

    2003-02-01

    This report describes the heat transfer problems associatedwith a liquid hydrogen absorber for the MICE experiment. This reportdescribes a technique for modeling heat transfer from the outside world,to the abosrber case and in its vacuum vessel, to the hydrogen and theninto helium gas at 14 K. Also presented are the equation for freeconvection cooling of the liquid hydrogen in the absorber.

  17. Absorber transmissivities in 57Fe Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Ballet, O.

    1985-01-01

    Some useful relations are derived for the polarization dependent optical index of 57 Fe Moessbauer absorbers. Real rotation matrices are extensively used and, besides wave-direction dependence, their properties simplify also the treatment of texture and f-anisotropy. The derivation of absorber transmissivities from the optical index is discussed with a special emphasis on line overlapping. (Auth.)

  18. Metamaterial Resonant Absorbers for Terahertz Sensing

    Science.gov (United States)

    2015-12-01

    process was completed in the NPS clean room for an Al/SiOx/Al metamaterial absorber . After fabrication, FTIR testing was employed to determine the...is unlimited METAMATERIAL RESONANT ABSORBERS FOR TERAHERTZ SENSING by Eric A. Stinson December 2015 Thesis Advisor: Gamani Karunasiri...

  19. Referral expectations of radiology

    International Nuclear Information System (INIS)

    Smith, W.L.; Altmaier, E.; Berberoglu, L.; Morris, K.

    1989-01-01

    The expectation of the referring physician are key to developing a successful practice in radiology. Structured interviews with 17 clinicians in both community care and academic practice documented that accuracy of the radiologic report was the single most important factor in clinician satisfaction. Data intercorrelation showed that accuracy of report correlated with frequency of referral (r = .49). Overall satisfaction of the referring physician with radiology correlated with accuracy (r = .69), patient satisfaction (r = .36), and efficiency in archiving (r = .42). These data may be weighted by departmental managers to allocate resources for improving referring physician satisfaction

  20. Liquid absorber experiments in ZED-2

    International Nuclear Information System (INIS)

    McDonnell, F.N.

    1975-07-01

    A set of liquid absorber experiments was performed in ZED-2 to provide data with which to test the adequacy of calculational methods for zone controller and refuelling studies associated with advanced reactor concepts. The absorber consisted of a full length aluminum tube, containing either i)H 2 O, ii)H 2 O + boron (2.5 mg/ml) or iii)H 2 O + boron (8.0 mg/ml). The tube was suspended vertically at interstitial or in-channel locations. A U-tube absorber was also simulated using two absorber tubes with appropriate spacers. Experiments were carried out at two different square lattice pitches, 22.86 and 27.94 cm. Measurements were made of the reactivity effects of the absorbers and, in some cases, of the detailed flux distribution near the perturbation. The results from one calculational method, the source-sink approach, were compared with the data from selected experiments. (author)

  1. ATLAS: Exceeding all expectations

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    “One year ago it would have been impossible for us to guess that the machine and the experiments could achieve so much so quickly”, says Fabiola Gianotti, ATLAS spokesperson. The whole chain – from collision to data analysis – has worked remarkably well in ATLAS.   The first LHC proton run undoubtedly exceeded expectations for the ATLAS experiment. “ATLAS has worked very well since the beginning. Its overall data-taking efficiency is greater than 90%”, says Fabiola Gianotti. “The quality and maturity of the reconstruction and simulation software turned out to be better than we expected for this initial stage of the experiment. The Grid is a great success, and right from the beginning it has allowed members of the collaboration all over the world to participate in the data analysis in an effective and timely manner, and to deliver physics results very quickly”. In just a few months of data taking, ATLAS has observed t...

  2. Probability via expectation

    CERN Document Server

    Whittle, Peter

    1992-01-01

    This book is a complete revision of the earlier work Probability which ap­ peared in 1970. While revised so radically and incorporating so much new material as to amount to a new text, it preserves both the aim and the approach of the original. That aim was stated as the provision of a 'first text in probability, de­ manding a reasonable but not extensive knowledge of mathematics, and taking the reader to what one might describe as a good intermediate level'. In doing so it attempted to break away from stereotyped applications, and consider applications of a more novel and significant character. The particular novelty of the approach was that expectation was taken as the prime concept, and the concept of expectation axiomatized rather than that of a probability measure. In the preface to the original text of 1970 (reproduced below, together with that to the Russian edition of 1982) I listed what I saw as the advantages of the approach in as unlaboured a fashion as I could. I also took the view that the text...

  3. Gender Roles and Expectations

    Directory of Open Access Journals (Sweden)

    Susana A. Eisenchlas

    2013-09-01

    Full Text Available One consequence of the advent of cyber communication is that increasing numbers of people go online to ask for, obtain, and presumably act upon advice dispensed by unknown peers. Just as advice seekers may not have access to information about the identities, ideologies, and other personal characteristics of advice givers, advice givers are equally ignorant about their interlocutors except for the bits of demographic information that the latter may offer freely. In the present study, that information concerns sex. As the sex of the advice seeker may be the only, or the predominant, contextual variable at hand, it is expected that that identifier will guide advice givers in formulating their advice. The aim of this project is to investigate whether and how the sex of advice givers and receivers affects the type of advice, through the empirical analysis of a corpus of web-based Spanish language forums on personal relationship difficulties. The data revealed that, in the absence of individuating information beyond that implicit in the advice request, internalized gender expectations along the lines of agency and communality are the sources from which advice givers draw to guide their counsel. This is despite the trend in discursive practices used in formulating advice, suggesting greater language convergence across sexes.

  4. Optical tomograph optimized for tumor detection inside highly absorbent organs

    Science.gov (United States)

    Boutet, Jérôme; Koenig, Anne; Hervé, Lionel; Berger, Michel; Dinten, Jean-Marc; Josserand, Véronique; Coll, Jean-Luc

    2011-05-01

    This paper presents a tomograph for small animal fluorescence imaging. The compact and cost-effective system described in this article was designed to address the problem of tumor detection inside highly absorbent heterogeneous organs, such as lungs. To validate the tomograph's ability to detect cancerous nodules inside lungs, in vivo tumor growth was studied on seven cancerous mice bearing murine mammary tumors marked with Alexa Fluor 700. They were successively imaged 10, 12, and 14 days after the primary tumor implantation. The fluorescence maps were compared over this time period. As expected, the reconstructed fluorescence increases with the tumor growth stage.

  5. Beam test of ferrite absorber in TRISTAN MR

    International Nuclear Information System (INIS)

    Tajima, T.; Asano, K.; Furuya, T.; Ishi, Y.; Kijima, Y.; Mitsunobu, S.; Sennyu, K.; Takahashi, T.

    1996-06-01

    A study on the effect of beams on the ferrite absorber was performed using TRISTAN MR. The tested absorber consists of a 300 mm-diam. copper pipe with 4 mm-thick ferrite inner layer, which was fabricated with Hot Isostatic Press (HIP) technique. No spark, damage, or degradation were observed up to the highest available single bunch current of 4.4 mA, i.e. 2.8x10 11 electrons per bunch, which is 8.5 times higher than that of KEKB low energy ring. The loss factor showed significant increase with bunch shortening, e.g. 2.6 V/pC at 4 mm was about 40% higher than the value predicted by the calculation assuming Gaussian bunch and no incoming power from outside of the chamber. (author)

  6. Medium response limitations in short pulse amplifiers and absorbers

    International Nuclear Information System (INIS)

    Schappert, G.T.

    1976-07-01

    This report reviews some of the basic considerations which determine temporal pulse characteristics in amplifiers and absorbers. To concentrate on analytical results, the amplification or absorption of a step pulse is worked out in detail. It is shown that in the small signal regime the medium response time of T 2 is modified because of propagation effects to T 2 gL/2 for an amplifier of gain g and length L and T 2 /αl for an absorber of loss coefficient 1 and length L. Once saturation sets in, general analytical results are no longer possible except in the T 2 → 0, or rate equation limit. However, combining the finite T 2 small signals results with the rate equation results one can estimate risetime effects. Coherent effects, such as π pulses and self induced transparency have not yet found applications in high power, high pressure gas lasers. (orig.) [de

  7. Absorber for wakefield interference management at the entrance of the wiggler of a free electron laser

    Energy Technology Data Exchange (ETDEWEB)

    Marchlik, Matthew; Biallas, George Herman

    2017-03-07

    A method for managing the broad band microwave and TeraHertz (THz) radiation in a free electron laser (FEL) having a wiggler producing power in the electromagnetic spectrum. The method includes placement of broadband microwave and TeraHertz (THz) radiation absorbers on the upstream end of the wiggler. The absorbers dampen the bounced back, broad band microwave and THz radiation returning from the surfaces outside the nose of the cookie-cutter and thus preventing broadening of the electron beam pulse's narrow longitudinal energy distribution. Broadening diminishes the ultimate laser power from the wiggler. The broadband microwave and THz radiation absorbers are placed on either side of the slot in the cookie-cutter that shapes the wake field wave of the electron pulse to the slot shape of the wiggler chamber aperture. The broad band microwave and THz radiation absorber is preferably a non-porous pyrolytic grade of graphite with small grain size.

  8. Method of absorbing UF6 from gaseous mixtures in alkamine absorbents

    International Nuclear Information System (INIS)

    Lafferty, R.H.; Smiley, S.H.; Radimer, K.J.

    1976-01-01

    A method is described for recovering UF 6 from gaseous mixtures by absorption in a liquid. The liquid absorbent must have a relatively low viscosity and at least one component of the absorbent is an alkamine having less than 3 carbon atoms bonded to the amino nitrogen, less than 2 of the carbon atoms other than those bonded to the amino nitrogen are free of the hydroxy radical and precipitate the absorbed uranium from the absorbent. At least one component of the absorbent is chosen from the group consisting of ethanolamine, diethanolamine, and 3-methyl-3-amino-propane-diol-1,2

  9. Parasitic oscillation suppression in solid state lasers using absorbing thin films

    Science.gov (United States)

    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.

  10. Vibration analysis on compact car shock absorber

    Science.gov (United States)

    Tan, W. H.; Cheah, J. X.; Lam, C. K.; Lim, E. A.; Chuah, H. G.; Khor, C. Y.

    2017-10-01

    Shock absorber is a part of the suspension system which provides comfort experience while driving. Resonance, a phenomenon where forced frequency is coinciding with the natural frequency has significant effect on the shock absorber itself. Thus, in this study, natural frequencies of the shock absorber in a 2 degree-of-freedom system were investigated using Wolfram Mathematica 11, CATIA, and ANSYS. Both theoretical and simulation study how will the resonance affect the car shock absorber. The parametric study on the performance of shock absorber also had been conducted. It is found that the failure tends to occur on coil sprung of the shock absorber before the body of the shock absorber is fail. From mathematical modelling, it can also be seen that higher vibration level occurred on un-sprung mass compare to spring mass. This is due to the weight of sprung mass which could stabilize as compared with the weight of un-sprung mass. Besides that, two natural frequencies had been obtained which are 1.0 Hz and 9.1 Hz for sprung mass and un-sprung mass respectively where the acceleration is recorded as maximum. In conclusion, ANSYS can be used to validate with theoretical results with complete model in order to match with mathematical modelling.

  11. Synchronous and non-synchronous responses of systems with multiple identical nonlinear vibration absorbers

    Science.gov (United States)

    Issa, Jimmy S.; Shaw, Steven W.

    2015-07-01

    In this work we investigate the nonlinear dynamic response of systems composed of a primary inertia to which multiple identical vibration absorbers are attached. This problem is motivated by observations of systems of centrifugal pendulum vibration absorbers that are designed to reduce engine order torsional vibrations in rotating systems, but the results are relevant to translational systems as well. In these systems the total absorber mass is split into multiple equal masses for purposes of distribution and/or balance, and it is generally expected that the absorbers will act in unison, corresponding to a synchronous response. In order to capture nonlinear effects of the responses of the absorbers, specifically, their amplitude-dependent frequency, we consider them to possess nonlinear stiffness. The equations of motion for the system are derived and it is shown how one can uncouple the equations for the absorbers from that for the primary inertia, resulting in a system of identical resonators that are globally coupled. These symmetric equations are scaled for weak nonlinear effects, near resonant forcing, and small damping. The method of averaging is applied, from which steady-state responses and their stability are investigated. The response of systems with two, three, and four absorbers are considered in detail, demonstrating a rich variety of bifurcations of the synchronous response, resulting in responses with various levels of symmetry in which sub-groups of absorbers are mutually synchronous. It is also shown that undamped models with more than two absorbers possess a degenerate response, which is made robust by the addition of damping to the model. Design guidelines are proposed based on the nature of the system response, with the aim of minimizing the acceleration of the primary system. It is shown that the desired absorber parameters are selected so that the system achieves a stable synchronous response which does not undergo jumps via saddle

  12. Graphene and Graphene Metamaterials for Terahertz Absorbers

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Pizzocchero, Filippo; Booth, Tim

    2013-01-01

    Graphene, due to the possibility to tune its conductivity, is the promising material for a range of the terahertz (THz) applications, such as tunable reflectors, absorbers, modulators, filters and polarization converters. Subwavelength structuring of graphene in order to form metamaterials allows...... for even more control over the THz waves. In this poster presentation I will show an elegant way to describe the graphene metamaterials and the design of graphene based absorbers. I will also present our recent experimental results on the graphene absorbers characterization....

  13. Semiconductor saturable absorbers for ultrafast terahertz signals

    DEFF Research Database (Denmark)

    Hoffmann, Matthias C.; Turchinovich, Dmitry

    2010-01-01

    We demonstrate saturable absorber behavior of n-type semiconductors GaAs, GaP, and Ge in the terahertz THz frequency range at room temperature using nonlinear THz spectroscopy. The saturation mechanism is based on a decrease in electron conductivity of semiconductors at high electron momentum...... states, due to conduction band onparabolicity and scattering into satellite valleys in strong THz fields. Saturable absorber parameters, such as linear and nonsaturable transmission, and saturation fluence, are extracted by fits to a classic saturable absorber model. Further, we observe THz pulse...

  14. Wet scavenging of SO2 emissions around India's largest lignite based power plant

    Science.gov (United States)

    Rai, A.; Ghosh, S.; Chakraborty, S.

    2010-03-01

    The Neyveli Lignite Corporation (NLC) is among the largest lignite based power plants in South East Asia. The four elevated stacks from this power plant emanate a substantial amount of sulphur dioxide into a tropical boundary layer. Sulphur dioxide being a soluble pollutant gas is absorbed by falling raindrops. This is a first study that quantifies the scavenging action of the North Eastern monsoonal rains from a lignite based power plant. We find that although the North Eastern monsoonal rains have a preponderance of very large droplets, the contribution of the small droplets cannot be neglected. We expect that the estimated scavenging coefficients can be used by large eddy and climate models.

  15. Challenges, fears and expectations

    Directory of Open Access Journals (Sweden)

    Jože Urbanija

    1997-01-01

    Full Text Available The author deals with developmental projections in the future. In the light of the accelerated development of civilization periods, we can talk about postinformation era or at least about its characteristics which are directly related to basic questions of life and society and problems of survival concerning library and information sciences. In the frames of globalization and individualization, the users will turn from quantity of information to selective and quality ones.As to the contents, these information will be related to the basic facts of life and society and the problems of survival (globalization on one hand, while on the other, they will be more focused, more confined as to their contents and of higher quality necessary for individual performance and survival (individualization. In the background of these events, even more fears than today will be rising, related to loss of work, loss of professional identity, loss of the sense of meaning, loss of economical and social standard. From the actual situation and from the above mentioned fears expectations will arise. It will be possible to master the quantity of information with information and communication technologies and to enable access to them while human cognitive abilities will represent a bottleneck to their flow also in the future. An important field of the work of librarians in the future will be in the area of interdisciplinary connections with cognitive sciences.

  16. Expectations from ethics

    International Nuclear Information System (INIS)

    Fleming, P.

    2008-01-01

    Prof. Patricia Fleming, centred her presentation on ethical expectations in regulating safety for future generations. The challenge is to find a just solution, one that provides for a defensible approach to inter-generational equity. The question on equity is about whether we are permitted to treat generations differently and to still meet the demands of justice. And the question must be asked regarding these differences: 'in what ways do they make a moral difference?' She asked the question regarding the exact meaning of the ethical principle 'Radioactive waste shall be managed in such a way that predicted impacts on the health of future generations will not be greater than relevant levels of impact that are acceptable today'. Some countries have proposed different standards for different time periods, either implicitly or explicitly. In doing so, have they preserved our standards of justice or have they abandoned them? Prof. Fleming identified six points to provide with some moral maps which might be used to negotiate our way to a just solution to the disposal of nuclear waste. (author)

  17. Expectations and speech intelligibility.

    Science.gov (United States)

    Babel, Molly; Russell, Jamie

    2015-05-01

    Socio-indexical cues and paralinguistic information are often beneficial to speech processing as this information assists listeners in parsing the speech stream. Associations that particular populations speak in a certain speech style can, however, make it such that socio-indexical cues have a cost. In this study, native speakers of Canadian English who identify as Chinese Canadian and White Canadian read sentences that were presented to listeners in noise. Half of the sentences were presented with a visual-prime in the form of a photo of the speaker and half were presented in control trials with fixation crosses. Sentences produced by Chinese Canadians showed an intelligibility cost in the face-prime condition, whereas sentences produced by White Canadians did not. In an accentedness rating task, listeners rated White Canadians as less accented in the face-prime trials, but Chinese Canadians showed no such change in perceived accentedness. These results suggest a misalignment between an expected and an observed speech signal for the face-prime trials, which indicates that social information about a speaker can trigger linguistic associations that come with processing benefits and costs.

  18. Problems in radiation absorbed dose estimation from positron emitters

    International Nuclear Information System (INIS)

    Powell, G.F.; Harper, P.V.; Reft, C.S.; Chen, C.T.; Lathrop, K.A.

    1986-01-01

    The positron emitters commonly used in clinical imaging studies for the most part are short-lived, so that when they are distributed in the body the radiation absorbed dose is low even though most of the energy absorbed is from the positrons themselves rather than the annihilation radiation. These considerations do not apply to the administration pathway for a radiopharmaceutical where the activity may be highly concentrated for a brief period rather than distributed in the body. Thus, high local radiation absorbed doses to the vein for an intravenous administration and to the upper airways during administration by inhalation can be expected. For these geometries, beta point source functions (FPS's) have been employed to estimate the radiation absorbed dose in the present study. Physiologic measurements were done to determine other exposure parameters for intravenous administration of O-15 and Rb-82 and for administration of O-15-CO 2 by continuous breathing. Using FPS's to calculate dose rates to the vein wall from O-15 and Rb-82 injected into a vein having an internal radius of 1.5 mm yielded dose rates of 0.51 and 0.46 (rad x g/μCi x h), respectively. The dose gradient in the vein wall and surrounding tissues was also determined using FPS's. Administration of O-15-CO 2 by continuous breathing was also investigated. Using ultra-thin thermoluninescent dosimeters (TLD's) having the effective thickness of normal tracheal mucosa, experiments were performed in which 6 dosimeters were exposed to known concentrations of O-15 positrons in a hemicylindrical tracheal phantom having an internal radius of 0.96 cm and an effective length of 14 cm. The dose rate for these conditions was 3.4 (rads/h)/(μCi/cm 3 ). 15 references, 7 figures, 6 tables

  19. Neutron absorber qualification and acceptance testing from the designer's perspective

    International Nuclear Information System (INIS)

    Bracey, W.; Chiocca, R.

    2004-01-01

    Starting in the mid 1990's, the USNRC began to require less than 100% credit for the 10B present in fixed neutron absorbers spent fuel transport packages. The current practice in the US is to use only 75% of the specified 10B in criticality safety calculations unless extensive acceptance testing demonstrates both the presence of the 10B and uniformity of its distribution. In practice, the NRC has accepted no more than 90% credit for 10B in recent years, while other national competent authorities continue to accept 100%. More recently, with the introduction of new neutron absorber materials, particularly aluminum / boron carbide metal matrix composites, the NRC has also expressed expectations for qualification testing, based in large part on Transnuclear's successful application to use a new composite material in the TN-68 storage / transport cask. The difficulty is that adding more boron than is really necessary to a metal has some negative effects on the material, reducing the ductility and the thermal conductivity, and increasing the cost. Excessive testing requirements can have the undesired effect of keeping superior materials out of spent fuel package designs, without a corresponding justification based on public safety. In European countries and especially in France, 100% credit has been accepted up to now with materials controls specified in the Safety Analysis Report (SAR): Manufacturing process approved by qualification testing Materials manufacturing controlled under a Quality Assurance system. During fabrication, acceptance testing directly on products or on representative samples. Acceptance criteria taking into account a statistical uncertainty corresponding to 3σ. The original and current bases for the reduced 10 B credit, the design requirements for neutron absorber materials, and the experience of Transnuclear and Cogema Logistics with neutron absorber testing are examined. Guidelines for qualification and acceptance testing and process controls

  20. Bottom Slamming on Heaving Point Absorber Wave Energy Devices

    DEFF Research Database (Denmark)

    De Backer, Griet; Vantorre, Marc; Frigaard, Peter

    2010-01-01

    Oscillating point absorber buoys may rise out of the water and be subjected to bottom slamming upon re-entering the water. Numerical simulations are performed to estimate the power absorption, the impact velocities and the corresponding slamming forces for various slamming constraints. Three buoy...... occurrence probabilities can be significantly reduced by adapting the control parameters. The magnitude of the slamming load is severely influenced by the buoy shape. The ratio between the peak impact load on the hemisphere and that on the 45 cone is approximately 2, whereas the power absorption is only 4......-8% higher for the 45 degrees cone. This work illustrates the need to include slamming considerations aside from power absorption criteria in the buoy shape design process and the control strategy....

  1. Spacesuit Evaporator-Absorber-Radiator (SEAR)

    Data.gov (United States)

    National Aeronautics and Space Administration — The primary goal is to build and test a rigid Lithium Chloride Absorber Radiator (LCAR) coupon based on honeycomb geometry that would be applicable for EVA and...

  2. Absorbed dose uncertainty estimation for proton therapy

    Directory of Open Access Journals (Sweden)

    Spasić-Jokić Vesna

    2012-01-01

    Full Text Available Successful radiotherapy treatment depends on the absorbed dose evaluation and the possibility to define metrological characteristics of the therapy beam. Radiotherapy requires tumor dose delivery with expanded uncertainty less than ±5 %. It is particularly important to reduce uncertainty during therapy beam calibration as well as to apply all necessary ionization chamber correction factors. Absorbed dose to water was determined using ionometric method. Calibration was performed in reference cobalt beam. Combined standard uncertainty of the calculated absorbed dose to water in 65 MeV proton beam was ±1.97% while the obtained expanded uncertainty of absorbed dose for the same beam quality was ±5.02%. The uncertainty estimation method has been developed within the project TESLA.

  3. Energy absorber uses expanded coiled tube

    Science.gov (United States)

    Johnson, E. F.

    1972-01-01

    Mechanical shock mitigating device, based on working material to its failure point, absorbs mechanical energy by bending or twisting tubing. It functions under axial or tangential loading, has no rebound, is area independent, and is easy and inexpensive to build.

  4. Space Compatible Radar Absorbing Materials Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase 1 project shall investigate novel radar absorbing materials (RAM) for use in space or simulated space environments. These materials are lightweight...

  5. Quantitative neutron radiography using neutron absorbing honeycomb

    International Nuclear Information System (INIS)

    Tamaki, Masayoshi; Oda, Masahiro; Takahashi, Kenji; Ohkubo, Kohei; Tasaka, Kanji; Tsuruno, Akira; Matsubayashi, Masahito.

    1993-01-01

    This investigation concerns quantitative neutron radiography and computed tomography by using a neutron absorbing honeycomb collimator. By setting the neutron absorbing honeycomb collimator between object and imaging system, neutrons scattered in the object were absorbed by the honeycomb material and eliminated before coming to the imaging system, but the neutrons which were transmitted the object without interaction could reach the imaging system. The image by purely transmitted neutrons gives the quantitative information. Two honeycombs were prepared with coating of boron nitride and gadolinium oxide and evaluated for the quantitative application. The relation between the neutron total cross section and the attenuation coefficient confirmed that they were in a fairly good agreement. Application to quantitative computed tomography was also successfully conducted. The new neutron radiography method using the neutron-absorbing honeycomb collimator for the elimination of the scattered neutrons improved remarkably the quantitativeness of the neutron radiography and computed tomography. (author)

  6. An ultra-broadband multilayered graphene absorber

    KAUST Repository

    Amin, Muhammad

    2013-01-01

    An ultra-broadband multilayered graphene absorber operating at terahertz (THz) frequencies is proposed. The absorber design makes use of three mechanisms: (i) The graphene layers are asymmetrically patterned to support higher order surface plasmon modes that destructively interfere with the dipolar mode and generate electromagnetically induced absorption. (ii) The patterned graphene layers biased at different gate voltages backedup with dielectric substrates are stacked on top of each other. The resulting absorber is polarization dependent but has an ultra-broadband of operation. (iii) Graphene\\'s damping factor is increased by lowering its electron mobility to 1000cm 2=Vs. Indeed, numerical experiments demonstrate that with only three layers, bandwidth of 90% absorption can be extended upto 7THz, which is drastically larger than only few THz of bandwidth that can be achieved with existing metallic/graphene absorbers. © 2013 Optical Society of America.

  7. Actual behaviour of a ball vibration absorber

    Czech Academy of Sciences Publication Activity Database

    Pirner, Miroš

    2002-01-01

    Roč. 90, č. 8 (2002), s. 987-1005 ISSN 0167-6105 R&D Projects: GA ČR(CZ) GV103/96/K034 Institutional support: RVO:68378297 Keywords : TV towers * wind-excited vibrations * vibration absorbers * pendulum absorber Subject RIV: JM - Building Engineering Impact factor: 0.513, year: 2002 http://www.sciencedirect.com/science/article/pii/S0167610502002155#

  8. Multilayer Radar Absorbing Non-Woven Material

    Science.gov (United States)

    Dedov, A. V.; Nazarov, V. G.

    2016-06-01

    We study the electrical properties of multilayer radar absorbing materials obtained by adding nonwoven sheets of dielectric fibers with an intermediate layer of electrically conductive carbon fibers. Multilayer materials that absorb electromagnetic radiation in a wide frequency range are obtained by varying the content of the carbon fibers. The carbon-fiber content dependent mechanism of absorption of electromagnetic radiation by sheets and multilayer materials is considered.

  9. A Wedge Absorber Experiment at MICE

    Energy Technology Data Exchange (ETDEWEB)

    Neuffer, David [Fermilab; Mohayai, Tanaz [IIT, Chicago; Rogers, Chris [Rutherford; Snopok, Pavel [IIT, Chicago; Summers, Don [Mississippi U.

    2017-05-01

    Emittance exchange mediated by wedge absorbers is required for longitudinal ionization cooling and for final transverse emittance minimization for a muon collider. A wedge absorber within the MICE beam line could serve as a demonstration of the type of emittance exchange needed for 6-D cooling, including the configurations needed for muon colliders, as well as configurations for low-energy muon sources. Parameters for this test are explored in simulation and possible experimental configurations with simulated results are presented.

  10. Energy-Absorbing Passenger Seat for Aircraft

    Science.gov (United States)

    Eichelberger, C. P.; Alfaro-Bou, E.; Fasanella, E. L.

    1987-01-01

    Development of energy-absorbing passenger seat, designed to minimize injury in commercial-aircraft crash, part of joint FAA/NASA controlledimpact flight test of transport-category commercial aircraft. Modified seat mechanism collapses under heavy load to absorb impact energy and thereby protect passenger. Results of simulation tests indicate probability of passenger survival high. Proposed seat mechanism mitigates passenger injuries by reducing impact forces in crash.

  11. Semiconductor saturable absorbers for ultrafast THz signals

    DEFF Research Database (Denmark)

    Hoffmann, Matthias C.; Turchinovich, Dmitry

    We demonstrate saturable absorber behavior of n-type semiconductors in the THz frequency range using nonlinear THz spectroscopy. Further, we observe THz pulse shortening and increase of the group refractive index at high field strengths.......We demonstrate saturable absorber behavior of n-type semiconductors in the THz frequency range using nonlinear THz spectroscopy. Further, we observe THz pulse shortening and increase of the group refractive index at high field strengths....

  12. Phase Space Exchange in Thick Wedge Absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Neuffer, David [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2017-01-01

    The problem of phase space exchange in wedge absorbers with ionization cooling is discussed. The wedge absorber exchanges transverse and longitudinal phase space by introducing a position-dependent energy loss. In this paper we note that the wedges used with ionization cooling are relatively thick, so that single wedges cause relatively large changes in beam phase space. Calculation methods adapted to such “thick wedge” cases are presented, and beam phase-space transformations through such wedges are discussed.

  13. Expected years ever married

    Directory of Open Access Journals (Sweden)

    Ryohei Mogi

    2018-04-01

    Full Text Available Background: In the second half of the 20th century, remarkable marriage changes were seen: a great proportion of never married population, high average age at first marriage, and large variance in first marriage timing. Although it is theoretically possible to separate these three elements, disentangling them analytically remains a challenge. Objective: This study's goal is to answer the following questions: Which of the three effects, nonmarriage, delayed marriage, or expansion, has the most impact on nuptiality changes? How does the most influential factor differ by time periods, birth cohorts, and countries? Methods: To quantify nuptiality changes over time, we define the measure 'expected years ever married' (EYEM. We illustrate the use of EYEM, looking at time trends in 15 countries (six countries for cohort analysis and decompose these trends into three components: scale (the changes in the proportion of never married - nonmarriage, location (the changes in timing of first marriage - delayed marriage, and variance (the changes in the standard deviation of first marriage age - expansion. We used population counts by sex, age, and marital status from national statistical offices and the United Nations database. Results: Results show that delayed marriage is the most influential factor on period EYEM's changes, while nonmarriage has recently begun to contribute to the change in North and West Europe and Canada. Period and cohort analysis complement each other. Conclusions: This study introduces a new index of nuptiality and decomposes its change into the contribution of three components: scale, location, and variance. The decomposition steps presented here offer an open possibility for more elaborate parametric marriage models.

  14. Expectations from Society

    International Nuclear Information System (INIS)

    Blowers, A.

    2008-01-01

    Prof. A. Blowers observed that the social context within which radioactive waste management is considered has evolved over time. The early period where radioactive waste was a non-issue was succeeded by a period of intense conflict over solutions. The contemporary context is more consensual, in which solutions are sought that are both technically sound and socially acceptable. Among the major issues is that of inter-generational equity embraced in the question: how long can or should our responsibility to the future extend? He pointed out the differences in timescales. On the one hand, geo-scientific timescales are very long term, emphasizing the issue of how far into the future it is possible to make predictions about repository safety. By contrast, socio cultural timescales are much shorter, focusing on the foreseeable future of one or two generations and raising the issue of how far into the future we should be concerned. He listed. the primary expectations from society which are: safety and security to alleviate undue burdens to future generations and flexibility in order to enable the future generations to have a stake in decision making. The need to reconcile the two had led to a contemporary emphasis on phased geological disposal incorporating retrievability. However, the long timescales for implementation of disposal provided for sufficient flexibility without the need for retrievability. Future generations would inevitably have sold stake in decision making. Prof. A.. Blowers pointed out that society is also concerned with participation in decision making for implementation. The key elements for success are: openness and transparency, staged process, participation, partnership, benefits to enhance the well being of communities and a democratic framework for decision making, including the ratification of key decisions and the right for communities to withdraw from the process up to a predetermined point. This approach for decision making may also have

  15. Macro Expectations, Aggregate Uncertainty, and Expected Term Premia

    DEFF Research Database (Denmark)

    Dick, Christian D.; Schmeling, Maik; Schrimpf, Andreas

    2013-01-01

    Based on individual expectations from the Survey of Professional Forecasters, we construct a realtime proxy for expected term premium changes on long-term bonds. We empirically investigate the relation of these bond term premium expectations with expectations about key macroeconomic variables...... and in ation rates. Expectations about real macroeconomic variables seem to matter more than expectations about nominal factors. Additional findings on term structure factors suggest that the level and slope factor capture information related to uncertainty about real and nominal macroeconomic prospects...

  16. Macro Expectations, Aggregate Uncertainty, and Expected Term Premia

    DEFF Research Database (Denmark)

    Dick, Christian D.; Schmeling, Maik; Schrimpf, Andreas

    Based on individual expectations from the Survey of Professional Forecasters, we construct a realtime proxy for expected term premium changes on long-term bonds. We empirically investigate the relation of these bond term premium expectations with expectations about key macroeconomic variables...... and in ation rates. Expectations about real macroeconomic variables seem to matter more than expectations about nominal factors. Additional findings on term structure factors suggest that the level and slope factor capture information related to uncertainty about real and nominal macroeconomic prospects...

  17. Fabrication of PDMS/SWCNT thin films as saturable absorbers

    International Nuclear Information System (INIS)

    Hernandez-Romano, I; Sanchez-Mondragon, J J; Davila-Rodriguez, J; Delfyett, P J; May-Arrioja, D A

    2011-01-01

    We present a novel technique to fabricate a saturable absorber thin film based on Polydimethylsiloxane doped with Single Wall Carbon Nanotubes. Using this film a passive mode-locked fiber laser in a standard ring cavity configuration was built by inserting the film between two angled connectors. Self-starting passively mode-locked laser operation was easily observed. The generated pulses have a width of 1.26 ps at a repetition rate of 22.7 MHz with an average power of 4.89 mW.

  18. Multi-objective optimization of acoustic black hole vibration absorbers.

    Science.gov (United States)

    Shepherd, Micah R; Feurtado, Philip A; Conlon, Stephen C

    2016-09-01

    Structures with power law tapers exhibit the acoustic black hole (ABH) effect and can be used for vibration reduction. However, the design of ABHs for vibration reduction requires consideration of the underlying theory and its regions of validity. To address the competing nature of the best ABH design for vibration reduction and the underlying theoretical assumptions, a multi-objective approach is used to find the lowest frequency where both criteria are sufficiently met. The Pareto optimality curve is estimated for a range of ABH design parameters. The optimal set could then be used to implement an ABH vibration absorber.

  19. Social gradient in life expectancy and health expectancy in Denmark

    DEFF Research Database (Denmark)

    Brønnum-Hansen, Henrik; Andersen, Otto; Kjøller, Mette

    2004-01-01

    Health status of a population can be evaluated by health expectancy expressed as average lifetime in various states of health. The purpose of the study was to compare health expectancy in population groups at high, medium and low educational levels.......Health status of a population can be evaluated by health expectancy expressed as average lifetime in various states of health. The purpose of the study was to compare health expectancy in population groups at high, medium and low educational levels....

  20. Method of absorbance correction in a spectroscopic heating value sensor

    Science.gov (United States)

    Saveliev, Alexei; Jangale, Vilas Vyankatrao; Zelepouga, Sergeui; Pratapas, John

    2013-09-17

    A method and apparatus for absorbance correction in a spectroscopic heating value sensor in which a reference light intensity measurement is made on a non-absorbing reference fluid, a light intensity measurement is made on a sample fluid, and a measured light absorbance of the sample fluid is determined. A corrective light intensity measurement at a non-absorbing wavelength of the sample fluid is made on the sample fluid from which an absorbance correction factor is determined. The absorbance correction factor is then applied to the measured light absorbance of the sample fluid to arrive at a true or accurate absorbance for the sample fluid.

  1. Sectoral analysis in the European power and gas market. What is to be expected by the marketers?; Sektoruntersuchungen im europaeischen Strom- und Gasmarkt. Was haben die Marktbeteiligten zu erwarten?

    Energy Technology Data Exchange (ETDEWEB)

    Linsmeier, P. [Kanzlei Gleiss Lutz, Muenchen (Germany)

    2005-10-15

    Electric utilities are presently facing several official requests for information, among which were sectoral analysis of the Directorate General Competition in Brussels. The affected enterprises would be well advised to answer coherently and consistently. The Commission's latest surveys in the power and natural gas sector were carried out efficiency and emphatically and they reveal Brussels' will to create competitive markets.

  2. Star power

    International Nuclear Information System (INIS)

    Kennedy, Tom

    2003-01-01

    Discusses the fight over the diminishing supply of fossil fuels and how there could be an unlimited, clean and politically free source of power just over the horizon. Fusion was discovered as a much better, inexhaustable supply of power, it only takes a few atoms to fuse for fusion to take off. Fusion once started will continue until all the fuel is exhausted. It is expected, that with the current rate of progess, in fifty years time scientists will achieve practical fusion power

  3. Warm Absorber Diagnostics of AGN Dynamics

    Science.gov (United States)

    Kallman, Timothy

    Warm absorbers and related phenomena are observable manifestations of outflows or winds from active galactic nuclei (AGN) that have great potential value. Understanding AGN outflows is important for explaining the mass budgets of the central accreting black hole, and also for understanding feedback and the apparent co-evolution of black holes and their host galaxies. In the X-ray band warm absorbers are observed as photoelectric absorption and resonance line scattering features in the 0.5-10 keV energy band; the UV band also shows resonance line absorption. Warm absorbers are common in low luminosity AGN and they have been extensively studied observationally. They may play an important role in AGN feedback, regulating the net accretion onto the black hole and providing mechanical energy to the surroundings. However, fundamental properties of the warm absorbers are not known: What is the mechanism which drives the outflow?; what is the gas density in the flow and the geometrical distribution of the outflow?; what is the explanation for the apparent relation between warm absorbers and the surprising quasi-relativistic 'ultrafast outflows' (UFOs)? We propose a focused set of model calculations that are aimed at synthesizing observable properties of warm absorber flows and associated quantities. These will be used to explore various scenarios for warm absorber dynamics in order to answer the questions in the previous paragraph. The guiding principle will be to examine as wide a range as possible of warm absorber driving mechanisms, geometry and other properties, but with as careful consideration as possible to physical consistency. We will build on our previous work, which was a systematic campaign for testing important class of scenarios for driving the outflows. We have developed a set of tools that are unique and well suited for dynamical calculations including radiation in this context. We also have state-of-the-art tools for generating synthetic spectra, which are

  4. A Polarization-Dependent Frequency-Selective Metamaterial Absorber with Multiple Absorption Peaks

    Directory of Open Access Journals (Sweden)

    Guangsheng Deng

    2017-06-01

    Full Text Available A polarization-dependent, frequency-selective metamaterial (MM absorber based on a single-layer patterned resonant structure intended for F frequency band is proposed. The design, fabrication, and measurement for the proposed absorber are presented. The absorber’s absorption properties at resonant frequencies have unique characteristics of a single-band, dual-band, or triple-band absorption for different polarization of the incident wave. The calculated surface current distributions and power loss distribution provide further understanding of physical mechanism of resonance absorption. Moreover, a high absorption for a wide range of TE-polarized oblique incidence was achieved. Hence, the MM structure realized on a highly flexible polyimide film, makingthe absorber suitable for conformal geometry applications. The proposed absorber has great potential in the development of polarization detectors and polarizers.

  5. A high-performance broadband terahertz absorber based on sawtooth-shape doped-silicon

    Directory of Open Access Journals (Sweden)

    Liang-Hui Du

    2016-05-01

    Full Text Available Perfect absorbers with broadband absorption of terahertz (THz radiation are promising for applications in imaging and detection to enhance the contrast and sensitivity, as well as to provide concealment. Different from previous two-dimensional structures, here we put forward a new type of THz absorber based on sawtooth-shape doped-silicon with near-unit absorption across a broad spectral range. Absorbance over 99% is observed numerically from 1.2 to 3 THz by optimizing the geometric parameters of the sawtooth structure. Our absorbers can operate over a wide range of incident angle and are polarization insensitive. The underlying mechanisms due to the combination of an air-cavity mode and mode-matching resonance on the air-sawtooth interface are analyzed in terms of the field patterns and electromagnetic power loss features.

  6. Microstructure Analysis of Bismuth Absorbers for Transition-Edge Sensor X-ray Microcalorimeters

    Science.gov (United States)

    Yan, Daikang; Divan, Ralu; Gades, Lisa M.; Kenesei, Peter; Madden, Timothy J.; Miceli, Antonino; Park, Jun-Sang; Patel, Umeshkumar M.; Quaranta, Orlando; Sharma, Hemant; Bennett, Douglas A.; Doriese, William B.; Fowler, Joseph W.; Gard, Johnathon D.; Hays-Wehle, James P.; Morgan, Kelsey M.; Schmidt, Daniel R.; Swetz, Daniel S.; Ullom, Joel N.

    2018-03-01

    Given its large X-ray stopping power and low specific heat capacity, bismuth (Bi) is a promising absorber material for X-ray microcalorimeters and has been used with transition-edge sensors (TESs) in the past. However, distinct X-ray spectral features have been observed in TESs with Bi absorbers deposited with different techniques. Evaporated Bi absorbers are widely reported to have non-Gaussian low-energy tails, while electroplated ones do not show this feature. In this study, we fabricated Bi absorbers with these two methods and performed microstructure analysis using scanning electron microscopy and X-ray diffraction microscopy. The two types of material showed the same crystallographic structure, but the grain size of the electroplated Bi was about 40 times larger than that of the evaporated Bi. This distinction in grain size is likely to be the cause of their different spectral responses.

  7. Distributed Absorber for Noise and Vibration Control

    Directory of Open Access Journals (Sweden)

    Michel Azoulay

    2011-01-01

    Full Text Available An approach to a wide-band frequency passive vibration attenuation is introduced in this paper. This aims to suppress noise and vibration of extended multimode objects like plates, panels and shells. The absorber is arranged in the form of a single-layer assembly of small inertial bodies (balls being distributed and moulded within the light visco-elastic media (e.g. silicone resin. The absorber as a whole is embedded into object face covering the critical patches of the system surface. For the purpose of characterization, the authors introduced the complex frequency response function relating the volume velocity produced by the vibrating object surface (response stimulated by a point-wise force (stimulus applied to a particular point. The simulation and optimization of the main frequency characteristics has been performed using a full scale 3-dimensional Finite Element model. These revealed some new dynamic features of absorber's structures, which can contribute to vibration attenuation. A full-scale physical experimentation with synthesised absorber's structures confirmed the main results of simulation and has shown significant noise reduction over a staggering 0–20 kHz frequency band. This was achieved with a negligible weight and volume penalty due to the addition of the absorber. The results can find multiple applications in noise and vibration control of different structures. Some examples of such applications are presented.

  8. Identifying the perfect absorption of metamaterial absorbers

    Science.gov (United States)

    Duan, G.; Schalch, J.; Zhao, X.; Zhang, J.; Averitt, R. D.; Zhang, X.

    2018-01-01

    We present a detailed analysis of the conditions that result in unity absorption in metamaterial absorbers to guide the design and optimization of this important class of functional electromagnetic composites. Multilayer absorbers consisting of a metamaterial layer, dielectric spacer, and ground plane are specifically considered. Using interference theory, the dielectric spacer thickness and resonant frequency for unity absorption can be numerically determined from the functional dependence of the relative phase shift of the total reflection. Further, using transmission line theory in combination with interference theory we obtain analytical expressions for the unity absorption resonance frequency and corresponding spacer layer thickness in terms of the bare resonant frequency of the metamaterial layer and metallic and dielectric losses within the absorber structure. These simple expressions reveal a redshift of the unity absorption frequency with increasing loss that, in turn, necessitates an increase in the thickness of the dielectric spacer. The results of our analysis are experimentally confirmed by performing reflection-based terahertz time-domain spectroscopy on fabricated absorber structures covering a range of dielectric spacer thicknesses with careful control of the loss accomplished through water absorption in a semiporous polyimide dielectric spacer. Our findings can be widely applied to guide the design and optimization of the metamaterial absorbers and sensors.

  9. Absorbed dose determination in water. I

    International Nuclear Information System (INIS)

    Novotny, J.

    1991-01-01

    The use of new values of physical parameters as recommended by international organizations has consequences in radiotherapy, e.g. in the determination of absorbed doses in water based on ionometric measurements. A procedure is proposed for the determination of the conversion factor K w,u between kerma in air and absorbed dose in water, and of the factor C w,u between exposure measured and absorbed dose in water, for ionization chambers and high-energy photon beams. The conversion factors depend not only on the radiation quality but also on the dimensions and composition of the chamber and of the cup used in the calibrations. Numerical values are given for conventional kinds of ionization chambers. (author). 3 tabs., 16 refs

  10. Absorbed dose determination in water. II

    International Nuclear Information System (INIS)

    Novotny, J.; Hobzova, L.; Kindlova, A.

    1991-01-01

    The use of new values of physical parameters as recommended by international organizations has consequences in radiotherapy, e.g. in the determination of absorbed doses in water based on ionometric measurements. A procedure is proposed for the determination of the conversion factor K w,e from kerma in air to absorbed dose in water, and of the conversion factor C w,e from exposure measured to dose absorbed in water, this for ionization chambers and high-energy electron beams. The conversion factors depend not only on the radiation quality and measurement depth in the phantom but also on the dimensions and composition of the chamber and of the cup used in the calibrations. Numerical values are given for two conventional kinds of ionization chambers. (author). 3 tabs., 9 refs

  11. Ferrite HOM Absorber for the RHIC ERL

    Energy Technology Data Exchange (ETDEWEB)

    Hahn,H.; Choi, E.M.; Hammons, L.

    2008-10-01

    A superconducting Energy Recovery Linac is under construction at Brookhaven National Laboratory to serve as test bed for RHIC upgrades. The damping of higher-order modes in the superconducting five-cell cavity for the Energy-Recovery linac at RHIC is performed exclusively by two ferrite absorbers. The ferrite properties have been measured in ferrite-loaded pill box cavities resulting in the permeability values given by a first-order Debye model for the tiled absorber structure and an equivalent permeability value for computer simulations with solid ring dampers. Measured and simulated results for the higher-order modes in the prototype copper cavity are discussed. First room-temperature measurements of the finished niobium cavity are presented which confirm the effective damping of higher-order modes in the ERL. by the ferrite absorbers.

  12. Properties of CGM-Absorbing Galaxies

    Science.gov (United States)

    Hamill, Colin; Conway, Matthew; Apala, Elizabeth; Scott, Jennifer

    2018-01-01

    We extend the results of a study of the sightlines of 45 low-redshift quasars (0.06 COS that lie within the Sloan Digital Sky Survey. We have used photometric data from the SDSS DR12, along with the known absorption characteristics of the intergalactic medium and circumgalactic medium, to identify the most probable galaxy matches to absorbers in the spectroscopic dataset. Here, we use photometric data and measured galaxy parameters from SDSS DR12 to examine the distributions of galaxy properties such as virial radius, morphology, and position angle among those that match to absorbers within a specific range of impact parameters. We compare those distributions to galaxies within the same impact parameter range that are not matched to any absorber in the HST/COS spectrum in order to investigate global properties of the circumgalactic medium.

  13. Quantum walk with one variable absorbing boundary

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Feiran [Key Laboratory of Quantum Information and Quantum Optoelectronic Devices, Shaanxi Province, Xi' an Jiaotong University, Xi' an 710049 (China); Department of Applied Physics, School of Science, Xi' an Jiaotong University, Xi' an 710049 (China); Zhang, Pei, E-mail: zhangpei@mail.ustc.edu.cn [Key Laboratory of Quantum Information and Quantum Optoelectronic Devices, Shaanxi Province, Xi' an Jiaotong University, Xi' an 710049 (China); Department of Applied Physics, School of Science, Xi' an Jiaotong University, Xi' an 710049 (China); Wang, Yunlong; Liu, Ruifeng; Gao, Hong; Li, Fuli [Key Laboratory of Quantum Information and Quantum Optoelectronic Devices, Shaanxi Province, Xi' an Jiaotong University, Xi' an 710049 (China); Department of Applied Physics, School of Science, Xi' an Jiaotong University, Xi' an 710049 (China)

    2017-01-15

    Quantum walks constitute a promising ingredient in the research on quantum algorithms; consequently, exploring different types of quantum walks is of great significance for quantum information and quantum computation. In this study, we investigate the progress of quantum walks with a variable absorbing boundary and provide an analytical solution for the escape probability (the probability of a walker that is not absorbed by the boundary). We simulate the behavior of escape probability under different conditions, including the reflection coefficient, boundary location, and initial state. Moreover, it is also meaningful to extend our research to the situation of continuous-time and high-dimensional quantum walks. - Highlights: • A novel scheme about quantum walk with variable boundary is proposed. • The analytical results of the survival probability from the absorbing boundary. • The behavior of survival probability under different boundary conditions. • The influence of different initial coin states on the survival probability.

  14. Tribology Aspect of Rubber Shock Absorbers Development

    Directory of Open Access Journals (Sweden)

    M. Banić

    2013-09-01

    Full Text Available Rubber is a very flexible material with many desirable properties Which enable its broad use in engineering practice. Rubber or rubber-metal springs are widely used as anti-vibration or anti-shock components in technical systems. Rubber-metal springs are usually realized as a bonded assembly, however especially in shock absorbers, it is possible to realize free contacts between rubber and metal parts. In previous research it authors was observed that friction between rubber and metal in such case have a significant influence on the damping characteristics of shock absorber. This paper analyzes the development process of rubber or rubber-metal shock absorbers realized free contacts between the constitutive parts, starting from the design, construction, testing and operation, with special emphasis on the development of rubber-metal springs for the buffing and draw gear of railway vehicles.

  15. Cooling systems and hybrid A/C systems using an electromagnetic radiation-absorbing complex

    Science.gov (United States)

    Halas, Nancy J.; Nordlander, Peter; Neumann, Oara

    2015-05-19

    A method for powering a cooling unit. The method including applying electromagnetic (EM) radiation to a complex, where the complex absorbs the EM radiation to generate heat, transforming, using the heat generated by the complex, a fluid to vapor, and sending the vapor from the vessel to a turbine coupled to a generator by a shaft, where the vapor causes the turbine to rotate, which turns the shaft and causes the generator to generate the electric power, wherein the electric powers supplements the power needed to power the cooling unit

  16. Power Electronics

    DEFF Research Database (Denmark)

    Iov, Florin; Ciobotaru, Mihai; Blaabjerg, Frede

    2008-01-01

    The global electrical energy consumption is still rising and there is an urgent demand to increase the power capacity. It is expected that the power capacity has to be doubled within 20 years. The production, distribution and use of energy should be as efficient as possible and incentives to save...... energy at the end-user should also be set up. Deregulation of energy has in the past lowered the investment in larger power plants, which means the need for new electrical power sources will be high in the near future. Two major technologies will play important roles to solve the future problems. One...... is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most...

  17. Origami-inspired metamaterial absorbers for improving the larger-incident angle absorption

    International Nuclear Information System (INIS)

    Shen, Yang; Pang, Yongqiang; Wang, Jiafu; Ma, Hua; Pei, Zhibin; Qu, Shaobo

    2015-01-01

    When a folded resistive patch array stands up on a metallic plane, it can exhibit more outstanding absorption performance. Our theoretical investigations and simulations demonstrated that the folded resistive patch arrays can enhance the absorption bandwidth progressively with the increase of the incident angle for the oblique transverse magnetic incidence, which is contrary to the conventional resistive frequency selective surface absorber. On illumination, we achieved a 3D structure metamaterial absorber with the folded resistive patches. The proposed absorber is obtained from the inspiration of the origami, and it has broadband and lager-incident angle absorption. Both the simulations and the measurements indicate that the proposed absorber achieves the larger-incident angle absorption until 75° in the frequency band of 3.6–11.4 GHz. In addition, the absorber is extremely lightweight. The areal density of the fabricated sample is about 0.023 g cm −2 . Due to the broadband and lager-incident angle absorption, it is expected that the absorbers may find potential applications such as stealth technologies and electromagnetic interference. (paper)

  18. LINEAR MODEL FOR NON ISOSCELES ABSORBERS.

    Energy Technology Data Exchange (ETDEWEB)

    BERG,J.S.

    2003-05-12

    Previous analyses have assumed that wedge absorbers are triangularly shaped with equal angles for the two faces. In this case, to linear order, the energy loss depends only on the position in the direction of the face tilt, and is independent of the incoming angle. One can instead construct an absorber with entrance and exit faces facing rather general directions. In this case, the energy loss can depend on both the position and the angle of the particle in question. This paper demonstrates that and computes the effect to linear order.

  19. Multilayer detector for skin absorbed dose measuring

    International Nuclear Information System (INIS)

    Osanov, D.P.; Panova, V.P.; Shaks, A.I.

    1985-01-01

    A method for skin dosimetry based on utilization of multilayer detectors and permitting to estimate distribution of absorbed dose by skin depth is described. The detector represents a set of thin sensitive elements separated by tissue-equivalent absorbers. Quantitative evaluation and forecasting the degree of radiation injury of skin are determined by the formula based on determination of the probability of the fact that cells are not destroyed and they can divide further on. The given method ensures a possibility of quantitative evaluation of radiobiological effect and forecasting clinical consequences of skin irradiation by results of corresponding measurements of dose by means of the miultilayer detector

  20. Device for absorbing seismic effects on buildings

    International Nuclear Information System (INIS)

    Xercavins, Pierre; Pompei, Michel.

    1979-01-01

    Device for absorbing seismic effects. The construction or structure to be protected rests on its foundations through at least one footing formed of a stack of metal plates interlinked by layers of adhesive material, over at least a part of their extent, this material being an elastomer that can distort, characterized in that at least part of the area of some metal plates works in association with components which are able to absorb at least some of the energy resulting from friction during the relative movements of the metal plates against the distortion of the elastomer [fr

  1. Optimization of Perfect Absorbers with Multilayer Structures

    Science.gov (United States)

    Li Voti, Roberto

    2018-02-01

    We study wide-angle and broadband perfect absorbers with compact multilayer structures made of a sequence of ITO and TiN layers deposited onto a silver thick layer. An optimization procedure is introduced for searching the optimal thicknesses of the layers so as to design a perfect broadband absorber from 400 nm to 750 nm, for a wide range of angles of incidence from 0{°} to 50{°}, for both polarizations and with a low emissivity in the mid-infrared. We eventually compare the performances of several optimal structures that can be very promising for solar thermal energy harvesting and collectors.

  2. A novel regenerative shock absorber with a speed doubling mechanism and its Monte Carlo simulation

    Science.gov (United States)

    Zhang, Ran; Wang, Xu; Liu, Zhenwei

    2018-03-01

    A novel regenerative shock absorber has been designed and fabricated. The novelty of the presented work is the application of the double speed regenerative shock absorber that utilizes the rack and pinion mechanism to increase the magnet speed with respect to the coils for higher power output. The simulation models with parameters identified from finite element analysis and the experiments are developed. The proposed regenerative shock absorber is compared with the regenerative shock absorber without the rack and pinion mechanism, when they are integrated into the same quarter vehicle suspension system. The sinusoidal wave road profile displacement excitation and the random road profile displacement excitation with peak amplitude of 0.035 m are applied as the inputs in the frequency range of 0-25 Hz. It is found that with the sinusoidal and random road profile displacement input, the proposed innovative design can increase the output power by 4 times comparing to the baseline design. The proposed double speed regenerative shock absorber also presents to be more sensitive to the road profile irregularity than the single speed regenerative shock absorber as suggested by Monte Carlo simulation. Lastly the coil mass and amplification factor are studied for sensitivity analysis and performance optimization, which provides a general design method of the regenerative shock absorbers. It shows that for the system power output, the proposed design becomes more sensitive to either the coil mass or amplification factor depending on the amount of the coil mass. With the specifically selected combination of the coil mass and amplification factor, the optimized energy harvesting performance can be achieved.

  3. Absorber Model: the Halo-like model for the Lyman-α forest

    Science.gov (United States)

    Iršič, Vid; McQuinn, Matthew

    2018-04-01

    We present a semi-analytic model for the Lyman-α forest that is inspired by the Halo Model. This model is built on the absorption line decomposition of the forest. Flux correlations are decomposed into those within each absorption line (the 1-absorber term) and those between separate lines (the 2-absorber term), treating the lines as biased tracers of the underlying matter fluctuations. While the nonlinear exponential mapping between optical depth and flux requires an infinite series of moments to calculate any statistic, we show that this series can be re-summed (truncating at the desired order in the linear matter overdensity). We focus on the z=2–3 line-of-sight power spectrum. Our model finds that 1-absorber term dominates the power on all scales, with most of its contribution coming from H I columns of 1014–1015 cm‑2, while the smaller 2-absorber contribution comes from lower columns that trace overdensities of a few. The prominence of the 1-absorber correlations indicates that the line-of-sight power spectrum is shaped principally by the lines' number densities and their absorption profiles, with correlations between lines contributing to a lesser extent. We present intuitive formulae for the effective optical depth as well as the large-scale limits of 1-absorber and 2-absorber terms, which simplify to integrals over the H I column density distribution with different equivalent-width weightings. With minimalist models for the bias of absorption systems and their peculiar velocity broadening, our model predicts values for the density bias and velocity gradient bias that are consistent with those found in simulations.

  4. Diode-pumped passively Q-switched Nd:GGG laser with a Bi-doped GaAs semiconductor saturable absorber

    Science.gov (United States)

    Cong, Wen; Li, Dechun; Zhao, Shengzhi; Yang, Kejian; Li, Xiangyang; Qiao, Hui; Liu, Ji

    2014-12-01

    Passive Q-switching of a diode-pumped Nd:GGG laser is demonstrated using Bi-doped GaAs as saturable absorber. The Bi-doped GaAs wafer is fabricated by ion implantation and subsequent annealing. Compared with the Q-switched laser by undoped GaAs semiconductor saturable absorber, the laser with Bi-doped GaAs as saturable absorber can produce higher output power, shorter pulses, higher single pulse energies and higher peak powers. These results suggest that Bi-doped GaAs can be a promising new candidate of semiconductor saturable absorber in Q-switched laser.

  5. Light Absorbers and Catalysts for Solar to Fuel Conversion

    Science.gov (United States)

    Kornienko, Nikolay I.

    Increasing fossil fuel consumption and the resulting consequences to the environment has propelled research into means of utilizing alternative, clean energy sources. Solar power is among the most promising of renewable energy sources but must be converted into an energy dense medium such as chemical bonds to render it useful for transport and energy storage. Photoelectrochemistry (PEC), the splitting of water into oxygen and hydrogen fuel or reducing CO 2 to hydrocarbon fuels via sunlight is a promising approach towards this goal. Photoelectrochemical systems are comprised of several components, including light absorbers and catalysts. These parts must all synergistically function in a working device. Therefore, the continual development of each component is crucial for the overall goal. For PEC systems to be practical for large scale use, the must be efficient, stable, and composed of cost effective components. To this end, my work focused on the development of light absorbing and catalyst components of PEC solar to fuel converting systems. In the direction of light absorbers, I focused of utilizing Indium Phosphide (InP) nanowires (NWs) as photocathodes. I first developed synthetic techniques for InP NW solution phase and vapor phase growth. Next, I developed light absorbing photocathodes from my InP NWs towards PEC water splitting cells. I studied cobalt sulfide (CoSx) as an earth abundant catalyst for the reductive hydrogen evolution half reaction. Using in situ spectroscopic techniques, I elucidated the active structure of this catalyst and offered clues to its high activity. In addition to hydrogen evolution catalysts, I established a new generation of earth abundant catalysts for CO2 reduction to CO fuel/chemical feedstock. I first worked with molecularly tunable homogeneous catalysts that exhibited high selectivity for CO2 reduction in non-aqueous media. Next, in order to retain molecular tunability while achieving stability and efficiency in aqueous

  6. Feasibility of lignocellulose as feedstock for biological production of super absorbent polymers

    OpenAIRE

    Nystrand, Christoffer

    2010-01-01

    Super absorbent polymers (SAP) can absorb liquid many times its own weight and is used in diapers and incontinence pads. The most common type of SAP is cross-linked polyacrylic acid. The production of acrylic acid uses crude oil as starting material. This means that the final price of acrylic acid is affected by the price of crude oil which is expected to rise. This has led to an increasing interest in developing a sustainable bioproduction process that uses renewable lignocellulosic raw mate...

  7. Review of Plasmonic Nanocomposite Metamaterial Absorber

    Directory of Open Access Journals (Sweden)

    Mehdi Keshavarz Hedayati

    2014-02-01

    Full Text Available Plasmonic metamaterials are artificial materials typically composed of noble metals in which the features of photonics and electronics are linked by coupling photons to conduction electrons of metal (known as surface plasmon. These rationally designed structures have spurred interest noticeably since they demonstrate some fascinating properties which are unattainable with naturally occurring materials. Complete absorption of light is one of the recent exotic properties of plasmonic metamaterials which has broadened its application area considerably. This is realized by designing a medium whose impedance matches that of free space while being opaque. If such a medium is filled with some lossy medium, the resulting structure can absorb light totally in a sharp or broad frequency range. Although several types of metamaterials perfect absorber have been demonstrated so far, in the current paper we overview (and focus on perfect absorbers based on nanocomposites where the total thickness is a few tens of nanometer and the absorption band is broad, tunable and insensitive to the angle of incidence. The nanocomposites consist of metal nanoparticles embedded in a dielectric matrix with a high filling factor close to the percolation threshold. The filling factor can be tailored by the vapor phase co-deposition of the metallic and dielectric components. In addition, novel wet chemical approaches are discussed which are bio-inspired or involve synthesis within levitating Leidenfrost drops, for instance. Moreover, theoretical considerations, optical properties, and potential application of perfect absorbers will be presented.

  8. Selective mass transfer in a membrane absorber

    Science.gov (United States)

    Okunev, A. Yu.; Laguntsov, N. I.

    2006-09-01

    A theoretical study of selective mass transfer in a plane-frame membrane absorber (contactor) has been made. A mathematical model of the process has been developed and the process of purification of a gas mixture depending on the flow parameters, the membrane, and the feeding-mixture composition has been studied with its help.

  9. Review of Plasmonic Nanocomposite Metamaterial Absorber

    Science.gov (United States)

    Hedayati, Mehdi Keshavarz; Faupel, Franz; Elbahri, Mady

    2014-01-01

    Plasmonic metamaterials are artificial materials typically composed of noble metals in which the features of photonics and electronics are linked by coupling photons to conduction electrons of metal (known as surface _lasmon). These rationally designed structures have spurred interest noticeably since they demonstrate some fascinating properties which are unattainable with naturally occurring materials. Complete absorption of light is one of the recent exotic properties of plasmonic metamaterials which has broadened its application area considerably. This is realized by designing a medium whose impedance matches that of free space while being opaque. If such a medium is filled with some lossy medium, the resulting structure can absorb light totally in a sharp or broad frequency range. Although several types of metamaterials perfect absorber have been demonstrated so far, in the current paper we overview (and focus on) perfect absorbers based on nanocomposites where the total thickness is a few tens of nanometer and the absorption band is broad, tunable and insensitive to the angle of incidence. The nanocomposites consist of metal nanoparticles embedded in a dielectric matrix with a high filling factor close to the percolation threshold. The filling factor can be tailored by the vapor phase co-deposition of the metallic and dielectric components. In addition, novel wet chemical approaches are discussed which are bio-inspired or involve synthesis within levitating Leidenfrost drops, for instance. Moreover, theoretical considerations, optical properties, and potential application of perfect absorbers will be presented. PMID:28788511

  10. Moving core beam energy absorber and converter

    Science.gov (United States)

    Degtiarenko, Pavel V.

    2012-12-18

    A method and apparatus for the prevention of overheating of laser or particle beam impact zones through the use of a moving-in-the-coolant-flow arrangement for the energy absorbing core of the device. Moving of the core spreads the energy deposition in it in 1, 2, or 3 dimensions, thus increasing the effective cooling area of the device.

  11. MODELING AND SIMULATION OF INDUSTRIAL FORMALDEHYDE ABSORBERS

    NARCIS (Netherlands)

    WINKELMAN, JGM; SIJBRING, H; BEENACKERS, AACM; DEVRIES, ET

    1992-01-01

    The industrially important process of formaldehyde absorption in water constitutes a case of multicomponent mass transfer with multiple reactions and considerable heat effects. A stable solution algorithm is developed to simulate the performance of industrial absorbers for this process using a

  12. Electromagnetic and microwave absorbing properties of hollow ...

    Indian Academy of Sciences (India)

    bandwidth below −10 dB and minimum RL decrease with increasing thickness of HCNSs/paraffin composites. Keywords. Nanomaterials; nanospheres; CVD; electric; magnetic; microwave absorption properties. 1. Introduction. In recent years, microwave absorbing materials have attracted considerable attention because it ...

  13. Can polar bear hairs absorb environmental energy?

    OpenAIRE

    He Ji-Huan; Wang Qing-Li; Sun Jie

    2011-01-01

    A polar bear (Ursus maritimus) has superior ability to survive in harsh Arctic regions, why does the animal have such an excellent thermal protection? The present paper finds that the unique labyrinth cavity structure of the polar bear hair plays an important role. The hair can not only prevent body temperature loss but can also absorb energy from the environment.

  14. Can polar bear hairs absorb environmental energy?

    Directory of Open Access Journals (Sweden)

    He Ji-Huan

    2011-01-01

    Full Text Available A polar bear (Ursus maritimus has superior ability to survive in harsh Arctic regions, why does the animal have such an excellent thermal protection? The present paper finds that the unique labyrinth cavity structure of the polar bear hair plays an important role. The hair can not only prevent body temperature loss but can also absorb energy from the environment.

  15. Technology and assessment of neutron absorbing materials

    International Nuclear Information System (INIS)

    Kelly, B.T.; Murgatroyd, R.A.

    1977-06-01

    The present review assesses more recent developments in the technology and application of those absorber materials which are considered to be established or to have shown potential in reactor control. Emphasis is placed on physical, chemical and metallurgical properties and upon irradiation behaviour. (author)

  16. Absorbance and fluorescence studies on porphyrin Nanostructures ...

    African Journals Online (AJOL)

    The aim of this work was to study some photophysical properties of PNR for application as light harvester in dye sensitized solar cells. These properties included absorbance, fluorescence, and fluorescence quantum yield and lifetime. The results of Transmission Electron Microscope (TEM) images showed the formation of ...

  17. Expectations on Track? High School Tracking and Adolescent Educational Expectations

    DEFF Research Database (Denmark)

    Karlson, Kristian Bernt

    2015-01-01

    This paper examines the role of adaptation in expectation formation processes by analyzing how educational tracking in high schools affects adolescents' educational expectations. I argue that adolescents view track placement as a signal about their academic abilities and respond to it in terms...... of modifying their educational expectations. Applying a difference-in-differences approach to the National Educational Longitudinal Study of 1988, I find that being placed in an advanced or honors class in high school positively affects adolescents’ expectations, particularly if placement is consistent across...... subjects and if placement contradicts tracking experiences in middle school. My findings support the hypothesis that adolescents adapt their educational expectations to ability signals sent by schools....

  18. Decomposing change in life expectancy

    DEFF Research Database (Denmark)

    Vaupel, James W.; Canudas Romo, Vladimir

    2003-01-01

    We extend Nathan Keyfitz's research on continuous change in life expectancy over time by presenting and proving a new formula for decomposing such change. The formula separates change in life expectancy over time into two terms. The first term captures the general effect of reduction in death rates...... at all ages, and the second term captures the effect of heterogeneity in the pace of improvement in mortality at different ages. We extend the formula to decompose change in life expectancy into age-specific and cause-specific components, and apply the methods to analyze changes in life expectancy...

  19. Neutron absorbers and methods of forming at least a portion of a neutron absorber

    Science.gov (United States)

    Guillen, Donna P; Porter, Douglas L; Swank, W David; Erickson, Arnold W

    2014-12-02

    Methods of forming at least a portion of a neutron absorber include combining a first material and a second material to form a compound, reducing the compound into a plurality of particles, mixing the plurality of particles with a third material, and pressing the mixture of the plurality of particles and the third material. One or more components of neutron absorbers may be formed by such methods. Neutron absorbers may include a composite material including an intermetallic compound comprising hafnium aluminide and a matrix material comprising pure aluminum.

  20. The influence of radiative transfer on the turbulent flow inside solar absorbers operating with supercritical CO

    NARCIS (Netherlands)

    Pecnik, R.; Smit, S.H.H.J.; Patel, A.; Roekaerts, D.J.E.M.

    2016-01-01

    In this paper we investigate and compare two dierent solar receiver technologies for concentrated solar power plants operating with supercritical CO2. The rst receiver is based on conventional surface absorbers, while the second receiver is based on an innovative idea to use volumetric receivers

  1. Development of optical tools for the characterization of selective solar absorber at elevated temperature

    Science.gov (United States)

    Giraud, Philemon; Braillon, Julien; Delord, Christine; Raccurt, Olivier

    2016-05-01

    Durability of solar components for CSP (Concentrated Solar Power Plant) technologies is a key point to lower cost and ensure their large deployment. These technologies concentrated the solar radiation by means of mirrors on a receiver tube where it is collected as thermal energy. The absorbers are submitted to strong environmental constraints and the degradation of their optical properties (emittance and solar absorbance) have a direct impact on performance. The objective is to develop new optical equipment for characterization of this solar absorber in condition of use that is to say in air and at elevated temperature. In this paper we present two new optical test benches developed for optical characterization of solar absorbers in condition of use up to 800°C. The first equipment is an integrated sphere with heated sample holder which measures the hemispherical reflectance between 280 and 2500 nm to calculate the solar absorbance at high temperature. The second optical test bench measures the emittance of samples up to 1000°C in the range of 1.25 to 28.57 µm. Results of high temperature measurements on a series of metallic absorbers with selective coating and refractory material for high thermal receiver are presented.

  2. Nuclear Analysis for Application of Boron Burnable Absorber in the HANARO Fuel Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Chul Gyo; Choi, Wonwoo; Chae, Hee-Taek [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Seo, Keun Ho [Seoul National University, Seoul (Korea, Republic of)

    2016-10-15

    Development of the HANARO fuel element with burnable absorber was started in the U-Mo fuel development program at HANARO, and the first full core analysis was performed last year. In the analysis, cadmium in the form of CdO was considered as the most promising burnable absorber for the current HANARO element. The U-Mo fuel with CdO was successfully irradiated at the HANARO core, but it was found that the thermodynamic stability of CdO is questionable under the higher temperature condition than the current manufacturing environment. Prior to application of CdO, further studies are required. Traditionally, boron has been used as burnable absorber at the high performance research reactors such as ATR, FRM-II, etc. The power density of HANARO is lower than those reactors, and the residual reactivity effect by boron is not negligible in the core. Basic nuclear analysis for application of boron burnable absorber in the HANARO fuel assembly was performed for getting a better fuel element. The residual reactivity effect can be overcome with replacing the reduced fuel rods into the standard rods. This new fuel design provides lower reactivity swing and lower power peaking. To minimize the residual reactivity effect, a concept of heterogeneous burnable poison within the rod is introduced. The heterogeneous cases give us better results and there is an optimum boundary for the burnable absorber region. This neutronics study was limited to the boron burnable absorber in the current silicide HANARO fuel, other studies including manufacturing study are desirable for application of burnable absorber.

  3. An ultrathin wide-band planar metamaterial absorber based on a fractal frequency selective surface and resistive film

    International Nuclear Information System (INIS)

    Fan Yue-Nong; Cheng Yong-Zhi; Nie Yan; Wang Xian; Gong Rong-Zhou

    2013-01-01

    We propose an ultrathin wide-band metamaterial absorber (MA) based on a Minkowski (MIK) fractal frequency selective surface and resistive film. This absorber consists of a periodic arrangement of dielectric substrates sandwiched with an MIK fractal loop structure electric resonator and a resistive film. The finite element method is used to simulate and analyze the absorption of the MA. Compared with the MA-backed copper film, the designed MA-backed resistive film exhibits an absorption of 90% at a frequency region of 2 GHz–20 GHz. The power loss density distribution of the MA is further illustrated to explain the mechanism of the proposed MA. Simulated absorptions at different incidence cases indicate that this absorber is polarization-insensitive and wide-angled. Finally, further simulated results indicate that the surface resistance of the resistive film and the dielectric constant of the substrate can affect the absorbing property of the MA. This absorber may be used in many military fields

  4. Modelling of neutron absorbers in high temperature reactors by combined transport diffusion methods

    OpenAIRE

    Fen, V.; Lebedev, M.; Sarytchev, V.; Scherer, W.

    1992-01-01

    Today, the neutron-physical description of strong neutron absorbing materials for control and shut-down of nuclear power plants is performed using combined transport and diffusion methods. Two of these approaches are described and compared in this paper. The method of equivalent cross-sections has been developed at the KFA-Jülich Institute for Safety Research and Reactor Technology (ISR) and was widely used for all german HTR reactor concepts. The Obninsk Institute for Nuclear Power Engineeri...

  5. Fabrication of an Absorber-Coupled MKID Detector

    Science.gov (United States)

    Brown, Ari; Hsieh, Wen-Ting; Moseley, Samuel; Stevenson, Thomas; U-Yen, Kongpop; Wollack, Edward

    2012-01-01

    Absorber-coupled microwave kinetic inductance detector (MKID) arrays were developed for submillimeter and far-infrared astronomy. These sensors comprise arrays of lambda/2 stepped microwave impedance resonators patterned on a 1.5-mm-thick silicon membrane, which is optimized for optical coupling. The detector elements are supported on a 380-mm-thick micro-machined silicon wafer. The resonators consist of parallel plate aluminum transmission lines coupled to low-impedance Nb microstrip traces of variable length, which set the resonant frequency of each resonator. This allows for multiplexed microwave readout and, consequently, good spatial discrimination between pixels in the array. The transmission lines simultaneously act to absorb optical power and employ an appropriate surface impedance and effective filling fraction. The fabrication techniques demonstrate high-fabrication yield of MKID arrays on large, single-crystal membranes and sub-micron front-to-back alignment of the micro strip circuit. An MKID is a detector that operates upon the principle that a superconducting material s kinetic inductance and surface resistance will change in response to being exposed to radiation with a power density sufficient to break its Cooper pairs. When integrated as part of a resonant circuit, the change in surface impedance will result in a shift in its resonance frequency and a decrease of its quality factor. In this approach, incident power creates quasiparticles inside a superconducting resonator, which is configured to match the impedance of free space in order to absorb the radiation being detected. For this reason MKIDs are attractive for use in large-format focal plane arrays, because they are easily multiplexed in the frequency domain and their fabrication is straightforward. The fabrication process can be summarized in seven steps: (1) Alignment marks are lithographically patterned and etched all the way through a silicon on insulator (SOI) wafer, which consists of a

  6. Absorbed dose thresholds and absorbed dose rate limitations for studies of electron radiation effects on polyetherimides

    Science.gov (United States)

    Long, Edward R., Jr.; Long, Sheila Ann T.; Gray, Stephanie L.; Collins, William D.

    1989-01-01

    The threshold values of total absorbed dose for causing changes in tensile properties of a polyetherimide film and the limitations of the absorbed dose rate for accelerated-exposure evaluation of the effects of electron radiation in geosynchronous orbit were studied. Total absorbed doses from 1 kGy to 100 MGy and absorbed dose rates from 0.01 MGy/hr to 100 MGy/hr were investigated, where 1 Gy equals 100 rads. Total doses less than 2.5 MGy did not significantly change the tensile properties of the film whereas doses higher than 2.5 MGy significantly reduced elongation-to-failure. There was no measurable effect of the dose rate on the tensile properties for accelerated electron exposures.

  7. Intrascleral outflow after deep sclerectomy with absorbable and non-absorbable implants in the rabbit eye.

    Science.gov (United States)

    Kałużny, Jakub J; Grzanka, Dariusz; Wiśniewska, Halina; Niewińska, Alicja; Kałużny, Bartłomiej J; Grzanka, Alina

    2012-10-01

    The purpose of the study is an analysis of intrascleral drainage vessels formed in rabbits' eyes after non-penetrating deep sclerectomy (NPDS) with absorbable and non-absorbable implants, and comparison to eyes in which surgery was performed without implanted material. NPDS was carried out in 12 rabbits, with implantation of non-absorbable methacrylic hydrogel (N=10 eyes) or absorbable cross-linked sodium hyaluronate (N=6 eyes), or without any implant (N=8 eyes). All the animals were euthanized 1 year after surgery. Twenty-one eyeballs were prepared for light microscopy and 3 were prepared for transmission electron microscope (TEM) analysis. Aqueous humour pathways were stained with ferritin in 6 eyeballs. By light microscopy, small vessels adjacent to the areas of scarring were the most common abnormality. Vessel density was significantly higher in operated sclera compared to normal, healthy tissue, regardless of the type of implant used. The average vessel densities were 2.18±1.48 vessels/mm2 in non-implanted sclera, 2.34±1.69 vessels/mm2 in eyes with absorbable implants, and 3.64±1.78 vessels/mm2 in eyes with non-absorbable implants. Analysis of iron distribution in ferritin-injected eyes showed a positive reaction inside new aqueous draining vessels in all groups. TEM analysis showed that the ultrastructure of new vessels matched the features of the small veins. Aqueous outflow after NPDS can be achieved through the newly formed network of small intrascleral veins. Use of non-absorbable implants significantly increases vessel density in the sclera adjacent to implanted material compared to eyes in which absorbable implants or no implants were used.

  8. Solar Biogas Digester with Built-In Reverse Absorber Heater

    Directory of Open Access Journals (Sweden)

    Khasan S. Karimov

    2013-01-01

    Full Text Available In this work the design, fabrication and investigation of a solar biogas digester with built-in RAH (Reverse Absorber Heater is presented. The maximum temperature (50 o C inside of the methane tank was taken as a main parameter at the design of the digester. Using energy balance equation for the case of a static mass of fluid being heated; the parameters of thermal insulation of the methane tank were counted. The biogas digester is consisting of methane tank with built-in solar RAH to utilize solar energy for the heating of the slurry prepared from the different organic wastes (dung, sewage, food wastes etc. The methane tank was filled up to 70% of volume by organic wastes of the GIK Institute sewage, firstly, and secondly, by sewage and cow dung as well. During three months (October-December, 2009 and two months (February-March, 2010 the digester was investigated. The solar irradiance incident to the absorber, slurry's temperature and ambient temperature were measured. It was found that using sewage only and sewage with cow dung the retention times was 4 weeks and two weeks respectively and biogas quantity produced was 0.4 and 8.0 m 3 respectively. In addition, biogas upgradation scheme for removal of carbon dioxide, hydrogen sulphide and water vapor from biogas and conversion of biogas energy conversion into electric power is also discussed.

  9. Correlations in the three-dimensional Lyman-alpha forest contaminated by high column density absorbers

    Science.gov (United States)

    Rogers, Keir K.; Bird, Simeon; Peiris, Hiranya V.; Pontzen, Andrew; Font-Ribera, Andreu; Leistedt, Boris

    2018-03-01

    Correlations measured in three dimensions (3D) in the Lyman-alpha forest are contaminated by the presence of the damping wings of high column density (HCD) absorbing systems of neutral hydrogen (HI; having column densities N (H I) > 1.6 × 10^{17} atoms cm^{-2}), which extend significantly beyond the redshift-space location of the absorber. We measure this effect as a function of the column density of the HCD absorbers and redshift by measuring 3D flux power spectra in cosmological hydrodynamical simulations from the Illustris project. Survey pipelines exclude regions containing the largest damping wings. We find that, even after this procedure, there is a scale-dependent correction to the 3D Lyman-alpha forest flux power spectrum from residual contamination. We model this residual using a simple physical model of the HCD absorbers as linearly biased tracers of the matter density distribution, convolved with their Voigt profiles and integrated over the column density distribution function. We recommend the use of this model over existing models used in data analysis, which approximate the damping wings as top-hats and so miss shape information in the extended wings. The simple "linear Voigt model" is statistically consistent with our simulation results for a mock residual contamination up to small scales (|k| 0.4 h Mpc^{-1} for small damped Lyman-alpha absorbers; HCD absorbers with N (H I) ˜ 10^{21} atoms cm^{-2}). However, these systems are in any case preferentially removed from survey data. Our model is appropriate for an accurate analysis of the baryon acoustic oscillations (BAO) feature. It is additionally essential for reconstructing the full shape of the 3D flux power spectrum.

  10. Effect of the bio-absorbent on the microwave absorption property of the flaky CIPs/rubber absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Yang; Xu, Yonggang, E-mail: xuyonggang221@163.com; Cai, Jun; Yuan, Liming; Zhang, Deyuan

    2015-09-01

    Microwave absorbing composites filled with flaky carbonyl iron particles (CIPs) and the bio-absorbent were prepared by using a two-roll mixer and a vulcanizing machine. The electromagnetic (EM) parameters were measured by a vector network analyzer and the reflection loss (RL) was measured by the arch method in the frequency range of 1–4 GHz. The uniform dispersion of the absorbents was verified by comparing the calculated RL with the measured one. The results confirm that as the bio-absorbent was added, the permittivity was increased due to the volume content of absorbents, and the permeability was enlarged owing to the volume content of CIPs and interactions between the two absorbents. The composite filled with bio-absorbents achieved an excellent absorption property at a thickness of 1 mm (minimum RL reaches −7.8 dB), and as the RL was less than −10 dB the absorption band was widest (2.1–3.8 GHz) at a thickness of 2 mm. Therefore, the bio-absorbent is a promising additive candidate on fabricating microwave absorbing composites with a thinner thickness and wider absorption band. - Graphical abstract: Morphology of composites filled with flaky CIPs and the bio-absorbent. The enhancement of bio-absorbent on the electromagnetic absorption property of composites filled with flaky carbonyl iron particles (CIPs) is attributed to the interaction of the two absorbents. The volume content of the FCMPs with the larger shape CIPs play an important role in this effects, the composites filled with irons and bio-absorbents can achieve wider-band and thinner-thickness absorbing materials. - Highlights: • Absorbers filled with bio-absorbents and CIPs was fabricated. • Bio-absorbents enhanced the permittivity and permeability of the composites. • The absorbent interactions play a key role in the enhancement mechanism. • Bio-absorbents enhanced the composite RL in 1–4 GHz.

  11. Disposable Diaper Absorbency: Improvements via Advanced Designs.

    Science.gov (United States)

    Helmes, C Tucker; O'Connor, Robert; Sawyer, Larry; Young, Sharon

    2014-08-01

    Absorbency effectiveness in diapers has improved significantly in recent years with the advent of new ingredient combinations and advanced design features. With these features, many leading products maintain their dryness performance overnight. Considering the importance of holding liquid away from the skin, ongoing research in diaper construction focuses on strategies to increase the effectiveness to capture liquid and help avoid rewetting of infant skin. The layout and design of a disposable diaper allows for distribution of absorbency features where they can provide the optimal benefit. Clinical evidence indicates materials can keep moisture away from the skin in the diapered area, helping maintain proper skin hydration, minimizing irritation, and contributing to reduced rates of diaper rash. © The Author(s) 2014.

  12. Use of Wedge Absorbers in MICE

    Energy Technology Data Exchange (ETDEWEB)

    Neuffer, D. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Summers, D. [Univ. of Mississippi, Oxford, MS (United States); Mohayai, T. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); IIT, Chicago, IL (United States); Snopok, P. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); IIT, Chicago, IL (United States); Rogers, C. [Science and Technology Facilities Council (STFC), Oxford (United Kingdom). Rutherford Appleton Lab. (RAL)

    2017-03-01

    Wedge absorbers are needed to obtain longitudinal cooling in ionization cooling. They also can be used to obtain emittance exchanges between longitudinal and transverse phase space. There can be large exchanges in emittance, even with single wedges. In the present note we explore the use of wedge absorbers in the MICE experiment to obtain transverse–longitudinal emittance exchanges within present and future operational conditions. The same wedge can be used to explore “direct” and “reverse” emittance exchange dynamics, where direct indicates a configuration that reduces momentum spread and reverse is a configuration that increases momentum spread. Analytical estimated and ICOOL and G4BeamLine simulations of the exchanges at MICE parameters are presented. Large exchanges can be obtained in both reverse and direct configurations.

  13. Absorbing Software Testing into the Scrum Method

    Science.gov (United States)

    Tuomikoski, Janne; Tervonen, Ilkka

    In this paper we study, how to absorb software testing into the Scrum method. We conducted the research as an action research during the years 2007-2008 with three iterations. The result showed that testing can and even should be absorbed to the Scrum method. The testing team was merged into the Scrum teams. The teams can now deliver better working software in a shorter time, because testing keeps track of the progress of the development. Also the team spirit is higher, because the Scrum team members are committed to the same goal. The biggest change from test manager’s point of view was the organized Product Owner Team. Test manager don’t have testing team anymore, and in the future all the testing tasks have to be assigned through the Product Backlog.

  14. Theory of metasurface based perfect absorbers

    Science.gov (United States)

    Alaee, Rasoul; Albooyeh, Mohammad; Rockstuhl, Carsten

    2017-12-01

    Based on an analytic approach, we present a theoretical review on the absorption, scattering, and extinction of both dipole scatterers and regular arrays composed of such scatterers i.e. metasurfaces. Besides offering a tutorial by outlining the maximum absorption limit for electrically/magnetically resonant dipole particles/metasurfaces, we give an educative analytical approach to their analysis. Moreover, we put forward the analysis of two known alternatives in providing perfect absorbers out of electrically and or magnetically resonant metasurfaces; one is based on the simultaneous presence of both electric and magnetic responses in so called Huygens metasurfaces while the other is established upon the presence of a back reflector in so called Salisbury absorbers. Our work is supported by several numerical examples to clarify the discussions in each stage.

  15. Microstructured extremely thin absorber solar cells

    DEFF Research Database (Denmark)

    Biancardo, Matteo; Krebs, Frederik C

    2007-01-01

    In this paper we present the realization of extremely thin absorber (ETA) solar cells employing conductive glass substrates functionalized with TiO2 microstructures produced by embossing. Nanocrystalline or compact TiO2 films on Indium doped tin oxide (ITO) glass substrates were embossed by press......In this paper we present the realization of extremely thin absorber (ETA) solar cells employing conductive glass substrates functionalized with TiO2 microstructures produced by embossing. Nanocrystalline or compact TiO2 films on Indium doped tin oxide (ITO) glass substrates were embossed...... by pressing a silicon stamp containing a mu m size raised grid structure into the TiO2 by use of a hydraulic press (1 ton/50 cm(2)). The performance of these microstructured substrates in a ETA cell sensitized by a thermally evaporated or chemical bath deposited PbS film and completed by a PEDOT:PSS hole...

  16. Neural correlates of rhythmic expectancy

    Directory of Open Access Journals (Sweden)

    Theodore P. Zanto

    2006-01-01

    Full Text Available Temporal expectancy is thought to play a fundamental role in the perception of rhythm. This review summarizes recent studies that investigated rhythmic expectancy by recording neuroelectric activity with high temporal resolution during the presentation of rhythmic patterns. Prior event-related brain potential (ERP studies have uncovered auditory evoked responses that reflect detection of onsets, offsets, sustains,and abrupt changes in acoustic properties such as frequency, intensity, and spectrum, in addition to indexing higher-order processes such as auditory sensory memory and the violation of expectancy. In our studies of rhythmic expectancy, we measured emitted responses - a type of ERP that occurs when an expected event is omitted from a regular series of stimulus events - in simple rhythms with temporal structures typical of music. Our observations suggest that middle-latency gamma band (20-60 Hz activity (GBA plays an essential role in auditory rhythm processing. Evoked (phase-locked GBA occurs in the presence of physically presented auditory events and reflects the degree of accent. Induced (non-phase-locked GBA reflects temporally precise expectancies for strongly and weakly accented events in sound patterns. Thus far, these findings support theories of rhythm perception that posit temporal expectancies generated by active neural processes.

  17. Room Modal Equalisation with Electroacoustic Absorbers

    OpenAIRE

    Rivet, Etienne Thierry Jean-Luc

    2016-01-01

    The sound quality in a room is of fundamental importance for both recording and reproducing processes. Because of the room modes, the distributions in space and frequency of the sound field are largely altered. Excessive rise and decay times caused by the resonances might even mask some details at higher frequencies, and these irregularities may be heard as a coloration of the sound. To address this problem, passive absorbers are bulky and too inefficient to significantly improve the listen...

  18. Absorbed Doses to Patients in Nuclear Medicine

    International Nuclear Information System (INIS)

    Leide-Svegborn, Sigrid; Mattsson, Soeren; Nosslin, Bertil; Johansson, Lennart

    2004-09-01

    The work with a Swedish catalogue of radiation absorbed doses to patients undergoing nuclear medicine investigations has continued. After the previous report in 1999, biokinetic data and dose estimates (mean absorbed dose to various organs and tissues and effective dose) have been produced for a number of substances: 11 C- acetate, 11 C- methionine, 18 F-DOPA, whole antibody labelled with either 99m Tc, 111 In, 123 I or 131 I, fragment of antibody, F(ab') 2 labelled with either 99m Tc, 111 In, 123 I or 131 I and fragment of antibody, Fab' labelled with either 99m Tc, 111 In, 123 I or 131 I. The absorbed dose estimates for these substances have been made from published biokinetic information. For other substances of interest, e.g. 14 C-urea (children age 3-6 years), 14 C-glycocholic acid, 14 C-xylose and 14 C-triolein, sufficient literature data have not been available. Therefore, a large number of measurements on patients and volunteers have been carried out, in order to determine the biokinetics and dosimetry for these substances. Samples of breast milk from 50 mothers, who had been subject to nuclear medicine investigations, have been collected at various times after administration of the radiopharmaceutical to the mother. The activity concentration in the breast milk samples has been measured. The absorbed dose to various organs and tissues and the effective dose to the child who ingests the milk have been determined for 17 different radiopharmaceuticals. Based on these results revised recommendations for interruption of breast-feeding after nuclear medicine investigations are suggested

  19. On the comparison of absorbing regions methods

    OpenAIRE

    Ke , Weina; Yaacoubi , Slah; Mckeon , Peter

    2012-01-01

    International audience; Numerical simulation methods are very useful in Non Destructive Testing because they save time, lower cost and allow for the investigation of diverse experimental configurations. However, these methods consume relatively long CPU time and system memory. Different solutions exist to minimize these limitations. Absorbing region methods are among them when it’s possible. These kinds of regions are also made to minimize or eliminate the spurious reflections at the boundari...

  20. 2D Saturable Absorbers for Fibre Lasers

    Directory of Open Access Journals (Sweden)

    Robert I. Woodward

    2015-11-01

    Full Text Available Two-dimensional (2D nanomaterials are an emergent and promising platform for future photonic and optoelectronic applications. Here, we review recent progress demonstrating the application of 2D nanomaterials as versatile, wideband saturable absorbers for Q-switching and mode-locking fibre lasers. We focus specifically on the family of few-layer transition metal dichalcogenides, including MoS2, MoSe2 and WS2.

  1. Eliminating the non-Gaussian spectral response of X-ray absorbers for transition-edge sensors

    Energy Technology Data Exchange (ETDEWEB)

    Divan, Ralu [Argonne National Laboratory, Argonne, Illinois 60439, USA; Gades, Lisa M. [Argonne National Laboratory, Argonne, Illinois 60439, USA; Kenesei, Peter [Argonne National Laboratory, Argonne, Illinois 60439, USA; Madden, Timothy J. [Argonne National Laboratory, Argonne, Illinois 60439, USA; Miceli, Antonino [Argonne National Laboratory, Argonne, Illinois 60439, USA; Park, Jun-Sang [Argonne National Laboratory, Argonne, Illinois 60439, USA; Patel, Umeshkumar M. [Argonne National Laboratory, Argonne, Illinois 60439, USA; Quaranta, Orlando [Argonne National Laboratory, Argonne, Illinois 60439, USA; Northwestern Univeristy, Evanston, Illinois 60208, USA; Sharma, Hemant [Argonne National Laboratory, Argonne, Illinois 60439, USA; Bennett, Douglas A. [National Institute of Standards and Technology, Boulder, Colorado 80305, USA; Doriese, William B. [National Institute of Standards and Technology, Boulder, Colorado 80305, USA; Fowler, Joseph W. [National Institute of Standards and Technology, Boulder, Colorado 80305, USA; Gard, Johnathon D. [National Institute of Standards and Technology, Boulder, Colorado 80305, USA; University of Colorado, Boulder, Colorado 80309, USA; Hays-Wehle, James P. [National Institute of Standards and Technology, Boulder, Colorado 80305, USA; Morgan, Kelsey M. [National Institute of Standards and Technology, Boulder, Colorado 80305, USA; University of Colorado, Boulder, Colorado 80309, USA; Schmidt, Daniel R. [National Institute of Standards and Technology, Boulder, Colorado 80305, USA; Swetz, Daniel S. [National Institute of Standards and Technology, Boulder, Colorado 80305, USA; Ullom, Joel N. [National Institute of Standards and Technology, Boulder, Colorado 80305, USA; University of Colorado, Boulder, Colorado 80309, USA

    2017-11-06

    Transition-edge sensors (TESs) as microcalorimeters for high-energy-resolution X-ray spectroscopy are often fabricated with an absorber made of materials with high Z (for X-ray stopping power) and low heat capacity (for high resolving power). Bismuth represents one of the most compelling options. TESs with evaporated bismuth absorbers have shown spectra with undesirable and unexplained low-energy tails. We have developed TESs with electroplated bismuth absorbers over a gold layer that are not afflicted by this problem and that retain the other positive aspects of this material. To better understand these phenomena, we have studied a series of TESs with gold, gold/evaporated bismuth, and gold/electroplated bismuth absorbers, fabricated on the same die with identical thermal coupling. We show that the bismuth morphology is linked to the spectral response of X-ray TES microcalorimeters. Published by AIP Publishing.

  2. Eliminating the non-Gaussian spectral response of X-ray absorbers for transition-edge sensors

    Science.gov (United States)

    Yan, Daikang; Divan, Ralu; Gades, Lisa M.; Kenesei, Peter; Madden, Timothy J.; Miceli, Antonino; Park, Jun-Sang; Patel, Umeshkumar M.; Quaranta, Orlando; Sharma, Hemant; Bennett, Douglas A.; Doriese, William B.; Fowler, Joseph W.; Gard, Johnathon D.; Hays-Wehle, James P.; Morgan, Kelsey M.; Schmidt, Daniel R.; Swetz, Daniel S.; Ullom, Joel N.

    2017-11-01

    Transition-edge sensors (TESs) as microcalorimeters for high-energy-resolution X-ray spectroscopy are often fabricated with an absorber made of materials with high Z (for X-ray stopping power) and low heat capacity (for high resolving power). Bismuth represents one of the most compelling options. TESs with evaporated bismuth absorbers have shown spectra with undesirable and unexplained low-energy tails. We have developed TESs with electroplated bismuth absorbers over a gold layer that are not afflicted by this problem and that retain the other positive aspects of this material. To better understand these phenomena, we have studied a series of TESs with gold, gold/evaporated bismuth, and gold/electroplated bismuth absorbers, fabricated on the same die with identical thermal coupling. We show that the bismuth morphology is linked to the spectral response of X-ray TES microcalorimeters.

  3. An absorbed dose calorimeter for IMRT dosimetry

    International Nuclear Information System (INIS)

    Duane, S.; Aldehaybes, M.; Bailey, M.; Lee, N.D.; Thomas, C.G.; Palmans, H.

    2012-01-01

    A new calorimeter for dosimetry in small and complex fields has been built. The device is intended for the direct determination of absorbed dose to water in moderately small fields and in composite fields such as IMRT treatments, and as a transfer instrument calibrated against existing absorbed dose standards in conventional reference conditions. The geometry, materials and mode of operation have been chosen to minimize detector perturbations when used in a water phantom, to give a reasonably isotropic response and to minimize the effects of heat transfer when the calorimeter is used in non-reference conditions in a water phantom. The size of the core is meant to meet the needs of measurement in IMRT treatments and is comparable to the size of the air cavity in a type NE2611 ionization chamber. The calorimeter may also be used for small field dosimetry. Initial measurements in reference conditions and in an IMRT head and neck plan, collapsed to gantry angle zero, have been made to estimate the thermal characteristics of the device, and to assess its performance in use. The standard deviation (estimated repeatability) of the reference absorbed dose measurements was 0.02 Gy (0.6%). (authors)

  4. Thermal expansion absorbing structure for pipeline

    International Nuclear Information System (INIS)

    Nagata, Takashi; Yamashita, Takuya.

    1995-01-01

    A thermal expansion absorbing structure for a pipeline is disposed to the end of pipelines to form a U-shaped cross section connecting a semi-circular torus shell and a short double-walled cylindrical tube. The U-shaped longitudinal cross-section is deformed in accordance with the shrinking deformation of the pipeline and absorbs thermal expansion. Namely, since the central lines of the outer and inner tubes of the double-walled cylindrical tube deform so as to incline, when the pipeline is deformed by thermal expansion, thermal expansion can be absorbed by a simple configuration thereby enabling to contribute to ensure the safety. Then, the entire length of the pipeline can greatly be shortened by applying it to the pipeline disposed in a high temperature state compared with a method of laying around a pipeline using only elbows, which has been conducted so far. Especially, when it is applied to a pipeline for an FBR-type reactor, the cost for the construction of a facility of a primary systems can greater be reduced. In addition, it can be applied to a pipeline for usual chemical plants and any other structures requiring absorption of deformation. (N.H.)

  5. CO2 Absorbing Capacity of MEA

    Directory of Open Access Journals (Sweden)

    José I. Huertas

    2015-01-01

    Full Text Available We describe the use of a gas bubbler apparatus in which the gas phase is bubbled into a fixed amount of absorbent under standard conditions as a uniform procedure for determining the absorption capacity of solvents. The method was systematically applied to determine the CO2 absorbing capacity of MEA (Ac at several aqueous MEA (β and gas-phase CO2 concentrations. Ac approached the nominal CO2 absorbing capacity of MEA (720 g CO2/kg MEA at very low β levels, increasing from 447.9±18.1 to 581.3±32.3 g CO2/kg MEA as β was reduced from 30 to 2.5% (w/w. Ac did not depend on the CO2 concentration in the inlet gas stream as long as the gas stream did not include other amine sensitive components. During the bubbling tests the outlet CO2 concentration profiles exhibited a sigmoidal shape that could be described by an exponential equation characterized by an efficiency factor (a and a form factor (n. Statistical analysis based on correlation analysis indicated that in all cases the experimental data fit the equation well when a was 6.1±0.35 and n was 2.5±0.12. The results of these experiments may be used to optimize scrubber designs for CO2 sequestration from fossil fuel derived flue gases.

  6. Wide band cryogenic ultra-high vacuum microwave absorber

    Science.gov (United States)

    Campisi, I.E.

    1992-05-12

    An absorber waveguide assembly for absorbing higher order modes of microwave energy under cryogenic ultra-high vacuum conditions, that absorbs wide-band multi-mode energy. The absorber is of a special triangular shape, made from flat tiles of silicon carbide and aluminum nitride. The leading sharp end of the absorber is located in a corner of the waveguide and tapers to a larger cross-sectional area whose center is located approximately in the center of the wave guide. The absorber is relatively short, being of less height than the maximum width of the waveguide. 11 figs.

  7. Thermal and optical analysis of selective absorber coatings based on soot for applications in solar cookers

    Science.gov (United States)

    Servín, H.; Peña, M.; Sobral, H.; González, M.

    2017-01-01

    The thermal and optical properties of selective absorber coatings of a solar cooker have been investigated. Coatings have been prepared using soot from pine resin, wood stove and sugarcane, previously separated by size. Results show that the cooking power and the overall efficiency of these pots are higher than others painted with black primer. Besides, by using an integrating sphere, the diffuse reflectance of absorbers has been obtained. Lower values of the reflectance have been measured for the pots covered with soot, showing a high correlation with the results achieved from the thermal tests, considering the measurement errors.

  8. Simulation of spatial distribution of absorbed laser energy in spherical microcapsules

    Science.gov (United States)

    Geints, Yu E.; Zemlyanov, A. A.; Panina, E. K.

    2016-09-01

    Specific features of optical field distribution in composite spherical particles consisting of a liquid core and nanocomposite absorbing shell are theoretically studied at different wavelengths of incident radiation. Using the numerical simulation it is shown that the thickness of the shell of the spherical microcapsule particle and its intrinsic absorption coefficient determine the character of the spatial distribution and the absorbed power. The variation of these parameters allows one to change the spatial position of efficient volume absorption regions and peak absorption values. This provides favourable conditions for opening the shells in appropriate spatial zones to release the contents of the microcapsules.

  9. Design considerations for application of metallic honeycomb as an energy absorber

    International Nuclear Information System (INIS)

    Lee, W.H.; Roemer, R.E.

    1980-01-01

    Design for postulated accidents in nuclear power plants often requires mitigation of impact to safety-related structures. Plastically designed, energy absorbing mechanisms are often used in the design of such mitigating structures. Metallic honeycomb is the most efficient, practical, energy-absorbing material currently in use. Recent tests indicate that its use in this application, however, presents some unique design and fabrication problems. The paper presents the results of static and dynamic crush tests concerned with the effect of impact velocity, material properties, cell density, loading configuration, and overall pad geometry. Specific design recommendations are made in each area, and suggestions are provided to improve fabrication techniques and minimize subsequent problems

  10. Liquid carbon dioxide absorbents, methods of using the same, and related systems

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, Michael Joseph; Perry, Robert James; Lam, Tunchiao Hubert; Soloveichik, Grigorii Lev; Kniajanski, Sergei; Lewis, Larry Neil; Rubinsztajn, Malgorzata Iwona; Hancu, Dan

    2016-09-13

    A carbon dioxide absorbent composition is described, including (i) a liquid, nonaqueous silicon-based material, functionalized with one or more groups that either reversibly react with CO.sub.2 or have a high-affinity for CO.sub.2; and (ii) a hydroxy-containing solvent that is capable of dissolving both the silicon-based material and a reaction product of the silicon-based material and CO.sub.2. The absorbent may be utilized in methods to reduce carbon dioxide in an exhaust gas, and finds particular utility in power plants.

  11. Model of the absorbed dose on a small sphere into a gamma irradiation field

    International Nuclear Information System (INIS)

    Mangussi, J.

    2009-01-01

    Several models of the absorbed dose calculated as the energy deposited by the secondary electrons on a small volume sphere are presented. The calculations use the Compton scattering of a uniform photon beam in water, the photon attenuation and the electron stopping power are included. The sphere total absorbed dose is due to the stopping of the electrons generated in three regions: into the sphere volume, ahead and behind the sphere volume. Calculations are performed for spheres of different radius and placed at various depth of the vacuum - water interface. (author)

  12. Study of neutron absorbing microspheres in research reactors - Neutronic analyse

    International Nuclear Information System (INIS)

    Gana Watkins, Ignacio A.; Prado, Miguel O.; Mazufri, Claudio; Tunon, Juan M

    2012-01-01

    Now-a-days, it is increasingly common for nuclear power plants, as well as research reactors, to be designed and built with an alternative safety system aside from control rods. The acids and/or salts in solution injection systems is most frequently used. However, these systems present several implementation and operation problems due to the physical and chemical properties of the used compounds. After analyzing these drawbacks, we developed a new alternative safety system that contains the absorbing element isolated from the aqueous medium. In this context, it's proposed the use of aluminum borosilicate microspheres. The current paper presents erosion wear experiments to determine under which conditions microspheres can be considered as a potential component of a secondary shut down system in a nuclear facility (author)

  13. Multimodal tuned dynamic absorber for split Stirling linear cryocooler

    Science.gov (United States)

    Veprik, A.; Tuito, A.

    2017-02-01

    Forthcoming low size, weight, power and price split Stirling linear cryocoolers may rely on electro-dynamically driven single-piston compressors and pneumatically driven expanders interconnected by the configurable transfer line. For compactness, compressor and expander units may be placed in a side-by-side manner, thus producing tonal vibration export comprising force and moment components. In vibration sensitive applications, this may result in excessive angular line of sight jitter and translational defocusing affecting the image quality. The authors present Multimodal Tuned Dynamic Absorber (MTDA), having one translational and two tilting modes essentially tuned to the driving frequency. The dynamic reactions (force and moment) produced by such a MTDA are simultaneously counterbalancing force and moment vibration export produced by the cryocooler. The authors reveal the design details, the method of fine modal tuning and outcomes of numerical simulation on attainable performance.

  14. Porphyrin Based Near Infrared-Absorbing Materials for Organic Photovoltaics

    Science.gov (United States)

    Zhong, Qiwen

    The conservation and transformation of energy is essential to the survival of mankind, and thus concerns every modern society. Solar energy, as an everlasting source of energy, holds one of the key solutions to some of the most urgent problems the world now faces, such as global warming and the oil crisis. Advances in technologies utilizing clean, abundant solar energy, could be the steering wheel of our societies. Solar cells, one of the major advances in converting solar energy into electricity, are now capturing people's interest all over the globe. While solar cells have been commercially available for many years, the manufacturing of solar cells is quite expensive, limiting their broad based implementation. The cost of solar cell based electricity is 15-50 cents per kilowatt hour (¢/kwh), depending on the type of solar cell, compared to 0.7 ¢/kwh for fossil fuel based electricity. Clearly, decreasing the cost of electricity from solar cells is critical for their wide spread deployment. This will require a decrease in the cost of light absorbing materials and material processing used in fabricating the cells. Organic photovoltaics (OPVs) utilize organic materials such as polymers and small molecules. These devices have the advantage of being flexible and lower cost than conventional solar cells built from inorganic semiconductors (e.g. silicon). The low cost of OPVs is tied to lower materials and fabrication costs of organic cells. However, the current power conversion efficiencies of OPVs are still below 15%, while convention crystalline Si cells have efficiencies of 20-25%. A key limitation in OPVs today is their inability to utilize the near infrared (NIR) portion of the solar spectrum. This part of the spectrum comprises nearly half of the energy in sunlight that could be used to make electricity. The first and foremost step in conversion solar energy conversion is the absorption of light, which nature has provided us optimal model of, which is

  15. Super-absorbency and phase transition of gels in physiological salt solutions

    Science.gov (United States)

    Zhang, Yong-Qing; Tanaka, Toyoichi; Shibayama, Mitsuhiro

    1992-11-01

    IONIC gels with the ability to absorb many times their dry weight of water have found widespread use as absorbents in medical, chemical and agricultural applications1. The dramatic swelling power of these super-absorbent gels results from both the electrostatic repulsion between the charges on the polymer chains, and the osmotic pressure of the counter-ions2. In salt solutions such as saline, urine or blood, however, excess Na+ and Cl- ions screen the polymer charges and eliminate the osmotic imbalance, effectively changing the properties of the material to that of a non-ionic gel3: this greatly diminishes the swelling power, and hence the utility of these materials under physiological conditions. Here we report the development of a system combining a non-ionic gel with ionized surfactants, which shows super-absorbent behaviour even in the presence of salt. In water, the hydrophobic gel facilitates the formation of spherical surfactant micelles, which mimic the charged sites of an ionic gel. As the salt concentration is increased, the micelles become rod-like, maintaining the electrostatic repulsion along the polymer chains and thereby preserving the swelling power of the gel.

  16. Dialysis centers - what to expect

    Science.gov (United States)

    ... kidneys - dialysis centers; Dialysis - what to expect; Renal replacement therapy - dialysis centers; End-stage renal disease - dialysis ... to a tube that connects to the dialysis machine. Your blood will flow through the tube, into ...

  17. Life expectancy in bipolar disorder

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Vradi, Eleni; Andersen, Per Kragh

    2015-01-01

    OBJECTIVE: Life expectancy in patients with bipolar disorder has been reported to be decreased by 11 to 20 years. These calculations are based on data for individuals at the age of 15 years. However, this may be misleading for patients with bipolar disorder in general as most patients have a later...... onset of illness. The aim of the present study was to calculate the remaining life expectancy for patients of different ages with a diagnosis of bipolar disorder. METHODS: Using nationwide registers of all inpatient and outpatient contacts to all psychiatric hospitals in Denmark from 1970 to 2012 we...... remaining life expectancy in bipolar disorder and that of the general population decreased with age, indicating that patients with bipolar disorder start losing life-years during early and mid-adulthood. CONCLUSIONS: Life expectancy in bipolar disorder is decreased substantially, but less so than previously...

  18. Physical activity extends life expectancy

    Science.gov (United States)

    Leisure-time physical activity is associated with longer life expectancy, even at relatively low levels of activity and regardless of body weight, according to a study by a team of researchers led by the NCI.

  19. Small Molecules, Diversity and Great Expectations

    Indian Academy of Sciences (India)

    Small Molecules, Diversity and Great Expectations · PowerPoint Presentation · Slide 3 · Slide 4 · Slide 5 · Slide 6 · Slide 7 · Slide 8 · Slide 9 · Slide 10 · Slide 11 · Slide 12 · Slide 13 · Slide 14 · Slide 15 · Slide 16 · Slide 17 · Slide 18 · Slide 19 · Slide 20 · Slide 21 · Slide 22 · Slide 23 · Slide 24 · Slide 25 · Slide 26 · Slide 27.

  20. Inorganic UV absorbers for the photostabilisation of wood-clearcoating systems: Comparison with organic UV absorbers

    Science.gov (United States)

    Aloui, F.; Ahajji, A.; Irmouli, Y.; George, B.; Charrier, B.; Merlin, A.

    2007-02-01

    Inorganic UV absorbers which are widely used today were originally designed neither as a UV blocker in coatings applications, nor for wood protection. In recent years however, there has been extensive interest in these compounds, especially with regard to their properties as a UV blocker in coating applications. In this work, we carried out a comparative study to look into some inorganic and organic UV absorbers used in wood coating applications. The aim of this study is to determine the photostabilisation performances of each type of UV absorbers, to seek possible synergies and the influences of different wood species. We have also searched to find eventual correlation between these performances and the influence of UV absorbers on the film properties. Our study has compared the performances of the following UV absorbers: hombitec RM 300, hombitec RM 400 from the Sachtleben Company; transparent yellow and red iron oxides from Sayerlack as inorganic UV absorbers; organic UV absorbers Tinuvin 1130 and Tinuvin 5151 from Ciba Company. The study was carried out on three wood species: Abies grandis, tauari and European oak. The environmental constraints (in particular the limitation of the emission of volatile organic compounds VOCs) directed our choice towards aqueous formulations marketed by the Sayerlack Arch Coatings Company. The results obtained after 800 h of dry ageing showed that the Tinuvins and the hombitecs present better wood photostabilisations. On the other hand in wet ageing, with the hombitec, there are appearances of some cracks and an increase in the roughness of the surface. This phenomenon is absent when the Tinuvins are used. With regard to these results, the thermomechanical analyses relating to the follow-up of the change of the glass transition temperature ( Tg) of the various coating systems, show a different behaviour between the two types of absorbers. However, contrary to organic UV absorbers, inorganic ones tend to increase Tg during ageing

  1. Peculiarities of absorbed dose forming in some wild animals in Chornobyl exclusion zone

    Directory of Open Access Journals (Sweden)

    V. A. Gaychenko

    2015-10-01

    Full Text Available Based on field researches conducted in the exclusion zone of the Chernobyl nuclear power plant in the years after the accident, the peculiarities are identified of formation of absorbed doses in animals of different taxonomic and ecological groups that live in conditions of radioactive contamination of ecosystems. It was shown importance of consideration of radiation features on wild animals according to their life cycle, conditions and ways of life. Data were displayed about the importance of different types of irradiation according to the period of stay of the animals in the ground, in burrows and nests. The questions were reviewed about value of external and internal radiation in absorbed dose of different types of wildlife. Results of the calculation of the absorbed dose of bird embryos from egg shell were shown.

  2. Experimental study of acoustic radiation force of an ultrasound beam on absorbing and scattering objects

    Energy Technology Data Exchange (ETDEWEB)

    Nikolaeva, Anastasiia V., E-mail: niko200707@mail.ru; Kryzhanovsky, Maxim A.; Tsysar, Sergey A. [Department of Acoustics, Physics Faculty, Moscow State University, Leninskie Gory, Moscow 119991 (Russian Federation); Kreider, Wayne [Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, 1013 NE 40th St. Seattle WA 98105 (United States); Sapozhnikov, Oleg A. [Department of Acoustics, Physics Faculty, Moscow State University, Leninskie Gory, Moscow 119991 (Russian Federation); Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, 1013 NE 40th St. Seattle WA 98105 (United States)

    2015-10-28

    Acoustic radiation force is a nonlinear acoustic effect caused by the transfer of wave momentum to absorbing or scattering objects. This phenomenon is exploited in modern ultrasound metrology for measurement of the acoustic power radiated by a source and is used for both therapeutic and diagnostic sources in medical applications. To calculate radiation force an acoustic hologram can be used in conjunction with analytical expressions based on the angular spectrum of the measured field. The results of an experimental investigation of radiation forces in two different cases are presented in this paper. In one case, the radiation force of an obliquely incident ultrasound beam on a large absorber (which completely absorbs the beam) is considered. The second case concerns measurement of the radiation force on a spherical target that is small compared to the beam diameter.

  3. Effect of inclusions' distribution on microwave absorbing properties of composites

    International Nuclear Information System (INIS)

    Qin, Siliang; Wang, Qingguo; Qu, Zhaoming

    2013-01-01

    Effect of inclusions' spatial distributions on the permeability and permittivity of composites is studied using the generalized Maxwell-Garnett equations. The result indicates that inclusions' orientation distribution can increase the longitudinal electromagnetic parameters. For inclusions' random and orientation distribution, single and three-layer absorbers are designed and optimized using genetic algorithm. The result shows that under a given absorbing requirement, absorber with inclusions' orientation distribution is lighter and thinner than absorber with inclusions' random distribution.

  4. Absorbent material for type a radioactive materials packaging containing liquids

    International Nuclear Information System (INIS)

    Saunders, G.A.

    1989-11-01

    The application of absorbent materials to the packaging and transport of liquid radioactive materials in Type A packages has not been reported in the literature. However, a significant body of research exists on absorbent materials for personal hygiene products such as diapers. Absorption capacity is dependent on both the absorbent material and the liquid being absorbed. Theoretical principles for capillary absorption in both the horizontal and the vertical plane indicate that small contact angle between the absorbent fibre and the liquid, and a small inter-fibre pore size are important. Some fluid parameters such as viscosity affect the rate of absorption but not the final absorption capacity. There appears to be little comparability between results obtained for the same absorbent and fluid using different test procedures. Test samples of materials from several classes of potential absorbents have been evaluated in this study, and shown to have a wide range of absorbent capacities. Foams, natural fibres, artificial fibres and granular materials are all potentially useful absorbents, with capacities ranging from as little as 0.86 to as much as 40.6 grams of distilled water per gram of absorbent. Two experimental procedures for evaluating the absorbent capacity of these materials have been detailed in this report, and found suitable for evaluating granular, fibrous or foam materials. Compression of the absorbent material reduces its capacity, but parameters such as relative humidity, pH, temperature, and viscosity appear to have little significant influence on capacity. When the materials were loaded to 50% of their one-minute absorbency, subsequent loss of the absorbed liquid was generally minimal. All of the absorbent materials rapidly lost their absorbed water through evaporation within twenty-four hours in still air at 21 degrees C and 50% relative humidity

  5. On (m, n)-absorbing ideals of commutative rings

    Indian Academy of Sciences (India)

    with respect to various ring theoretic constructions and study (m, n)-absorbing ideals in several commutative rings. For example, in a Bézout ring or a Boolean ring, an ideal is an (m, n)-absorbing ideal if and only if it is an n-absorbing ideal, and in an almost. Dedekind domain every (m, n)-absorbing ideal is a product of at ...

  6. 21 CFR 880.5300 - Medical absorbent fiber.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical absorbent fiber. 880.5300 Section 880.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Devices § 880.5300 Medical absorbent fiber. (a) Identification. A medical absorbent fiber is a device...

  7. 21 CFR 868.5310 - Carbon dioxide absorber.

    Science.gov (United States)

    2010-04-01

    ... breathing circuit as a container for carbon dioxide absorbent. It may include a canister and water drain. (b... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Carbon dioxide absorber. 868.5310 Section 868.5310...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5310 Carbon dioxide absorber. (a...

  8. 21 CFR 886.3300 - Absorbable implant (scleral buckling method).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Absorbable implant (scleral buckling method). 886... SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Prosthetic Devices § 886.3300 Absorbable implant (scleral buckling method). (a) Identification. An absorbable implant (scleral buckling method) is a device...

  9. Organ absorbed doses in intraoral dental radiography.

    Science.gov (United States)

    Lecomber, A R; Faulkner, K

    1993-11-01

    A dental radiography unit operating at 70 kV (nominal) and 20 cm focus-skin distance was used to irradiate an anthropomorphic phantom loaded with lithium fluoride thermoluminescent dosemeters, in order to assess the variation in organ absorbed dose with intraoral periapical radiographic view. 14 views using the bisecting-angle technique and four views using the paralleling technique were studied. The results are presented and the doses and dose distributions examined. Doses for the paralleling and bisecting-angle techniques are compared, and the effects of focus-skin distance and beam collimation upon patient dosimetry discussed. Sources of uncertainty in dental dosimetry studies using phantoms are also considered.

  10. Acoustical model of a Shoddy fibre absorber

    Science.gov (United States)

    Manning, John Peter

    Shoddy fibres or "Shoddies" are a mixture of post-consumer and post-industrial fibres diverted from textile waste streams and recycled into their raw fibre form. They have found widespread use as a raw material for manufacturing sound absorbers that include, but are not limited to: automotive, architectural and home appliance applications. The purpose of this project is to develop a simple acoustic model to describe the acoustic behaviour of sound absorbers composed primarily of Shoddy fibres. The model requires knowledge of the material's bulk density only. To date, these materials have not been the focus of much published research and acoustical designers must rely on models that were developed for other materials or are overly complex. For modelling purposes, an equivalent fluid approach is chosen to balance complexity and accuracy. In deriving the proposed model, several popular equivalent fluid models are selected and the required input parameters for each model identified. The models are: the model of Delaney and Bazley, two models by Miki, the model of Johnson in conjunction with the model of Champoux and Allard and the model of Johnson in conjunction with the model of Lafarge. Characterization testing is carried out on sets of Shoddy absorbers produced using three different manufacturing methods. The measured properties are open porosity, tortuosity, airflow resistivity, the viscous and thermal characteristic lengths and the static thermal permeability. Empirical relationships between model parameters and bulk density are then derived and used to populate the selected models. This yields several 'simplified' models with bulk density as the only parameter. The most accurate model is then selected by comparing each model's prediction to the results of normal incidence sound absorption tests. The model of Johnson-Lafarge populated with the empirical relations is the most accurate model over the range of frequencies considered (approx. 300 Hz - 4000 Hz

  11. Liquid holdup in turbulent contact absorber

    International Nuclear Information System (INIS)

    Haq, A.; Zaman, M.; Inayat, M.H.; Chughtai, I.R.

    2009-01-01

    Dynamic liquid holdup in a turbulent contact absorber was obtained through quick shut off valves technique. Experiments were carried out in a Perspex column. Effects of liquid velocity, gas velocity, packing diameter packing density and packing height on dynamic liquid holdup were studied. Hollow spherical high density polyethylene (HDPE) balls were used as inert fluidized packing. Experiments were performed at practical range of liquid and gas velocities. Holdup was calculated on the basis of static bed height. Liquid holdup increases with increasing both liquid and gas velocities both for type 1 and type 2 modes of fluidization. Liquid holdup increases with packing density. No effect of dia was observed on liquid holdup. (author)

  12. Fabrication of high efficacy selective solar absorbers

    CSIR Research Space (South Africa)

    Tile, N

    2012-03-01

    Full Text Available Peer-Reviewed Journal Papers: K.T. Roro, N. Tile, B.W. Mwakikunga, B. Yalisi, A. Forbes (2012). Solar absorption and thermal emission properties of Multiwall carbonnanotube/nickel oxide nanocomposite thin films synthesized by sol-gel process..., Materials Science and Engineering B 177,581? 587. K.T. Roro, N. Tile, A. Forbes (2012), Preparation and characterization of carbon/nickel oxide nanocomposite coatings for solar absorber applications, Applied Surface Science 258, 7174? 7180. K.T. Roro...

  13. DHCAL with Minimal Absorber: Measurements with Positrons

    CERN Document Server

    Freund, B; Repond, J.; Schlereth, J.; Xia, L.; Dotti, A.; Grefe, C.; Ivantchenko, V.; Antequera, J.Berenguer; Calvo Alamillo, E.; Fouz, M.C.; Marin, J.; Puerta-Pelayo, J.; Verdugo, A.; Brianne, E.; Ebrahimi, A.; Gadow, K.; Göttlicher, P.; Günter, C.; Hartbrich, O.; Hermberg, B.; Irles, A.; Krivan, F.; Krüger, K.; Kvasnicka, J.; Lu, S.; Lutz, B.; Morgunov, V.; Provenza, A.; Reinecke, M.; Sefkow, F.; Schuwalow, S.; Tran, H.L.; Garutti, E.; Laurien, S.; Matysek, M.; Ramilli, M.; Schroeder, S.; Bilki, B.; Norbeck, E.; Northacker, D.; Onel, Y.; Cvach, J.; Gallus, P.; Havranek, M.; Janata, M.; Kovalcuk, M.; Kvasnicka, J.; Lednicky, D.; Marcisovsky, M.; Polak, I.; Popule, J.; Tomasek, L.; Tomasek, M.; Sicho, P.; Smolik, J.; Vrba, V.; Zalesak, J.; van Doren, B.; Wilson, G.W.; Kawagoe, K.; Hirai, H.; Sudo, Y.; Suehara, T.; Sumida, H.; Takada, S.; Tomita, T.; Yoshioka, T.; Bilokin, S.; Bonis, J.; Cornebise, P.; Pöschl, R.; Richard, F.; Thiebault, A.; Zerwas, D.; Hostachy, J.Y.; Morin, L.; Besson, D.; Chadeeva, M.; Danilov, M.; Markin, O.; Popova, E.; Gabriel, M.; Goecke, P.; Kiesling, C.; Kolk, N.van der; Simon, F.; Szalay, M.; Corriveau, F.; Blazey, G.C.; Dyshkant, A.; Francis, K.; Zutshi, V.; Kotera, K.; Ono, H.; Takeshita, T.; Ieki, S.; Kamiya, Y.; Ootani, W.; Shibata, N.; Jeans, D.; Komamiya, S.; Nakanishi, H.

    2016-01-01

    In special tests, the active layers of the CALICE Digital Hadron Calorimeter prototype, the DHCAL, were exposed to low energy particle beams, without being interleaved by absorber plates. The thickness of each layer corresponded approximately to 0.29 radiation lengths or 0.034 nuclear interaction lengths, defined mostly by the copper and steel skins of the detector cassettes. This paper reports on measurements performed with this device in the Fermilab test beam with positrons in the energy range of 1 to 10 GeV. The measurements are compared to simulations based on GEANT4 and a standalone program to emulate the detailed response of the active elements.

  14. Impedance matched thin metamaterials make metals absorbing.

    Science.gov (United States)

    Mattiucci, N; Bloemer, M J; Aközbek, N; D'Aguanno, G

    2013-11-13

    Metals are generally considered good reflectors over the entire electromagnetic spectrum up to their plasma frequency. Here we demonstrate an approach to tailor their absorbing characteristics based on the effective metamaterial properties of thin, periodic metallo-dielectric multilayers by exploiting a broadband, inherently non-resonant, surface impedance matching mechanism. Based on this mechanism, we design, fabricate and test omnidirectional, thin ( 99%) over a frequency range spanning from the UV to the IR. Our approach opens new venues to design cost effective materials for many applications such as thermo-photovoltaic energy conversion devices, light harvesting for solar cells, flat panel display, infrared detectors, stray light reduction, stealth and others.

  15. DHCAL with minimal absorber: measurements with positrons

    International Nuclear Information System (INIS)

    Freund, B.; Neubüser, C.; Repond, J.; Schlereth, J.; Xia, L.; Dotti, A.; Grefe, C.; Ivantchenko, V.; Antequera, J. Berenguer; Alamillo, E. Calvo; Fouz, M.-C.; Marin, J.; Puerta-Pelayo, J.; Verdugo, A.; Brianne, E.; Ebrahimi, A.; Gadow, K.; Göttlicher, P.; Günter, C.; Hartbrich, O.

    2016-01-01

    In special tests, the active layers of the CALICE Digital Hadron Calorimeter prototype, the DHCAL, were exposed to low energy particle beams, without being interleaved by absorber plates. The thickness of each layer corresponded approximately to 0.29 radiation lengths or 0.034 nuclear interaction lengths, defined mostly by the copper and steel skins of the detector cassettes. This paper reports on measurements performed with this device in the Fermilab test beam with positrons in the energy range of 1 to 10 GeV. The measurements are compared to simulations based on GEANT4 and a standalone program to emulate the detailed response of the active elements.

  16. An electromechanical low frequency panel sound absorber.

    Science.gov (United States)

    Chang, Daoqing; Liu, Bilong; Li, Xiaodong

    2010-08-01

    The sound absorbing properties of a thin micro-perforated plate (MPP) coated with piezoelectric material with shunt damping technology is investigated. First a theoretical model is presented to predict the sound absorption coefficients of a thin plate attached with a piezoelectric patch and electrical circuits. Then the model is extended to analyze the sound absorption for a thin plate with micro perforations and piezoelectric material. Measurements are also carried out in an impedance tube and found to be in good agreements with the theoretical model. The sound absorption of the constructions can be much improved by tuning the electrical circuits.

  17. High energy model for irregular absorbing particles

    International Nuclear Information System (INIS)

    Chiappetta, Pierre.

    1979-05-01

    In the framework of a high energy formulation of relativistic quantum scattering a model is presented which describes the scattering functions and polarization of irregular absorbing particles, whose dimensions are greater than the incident wavelength. More precisely in the forward direction an amplitude parametrization of eikonal type is defined which generalizes the usual diffraction theory, and in the backward direction a reflective model is used including a shadow function. The model predictions are in good agreement with the scattering measurements off irregular compact and fluffy particles performed by Zerull, Giese and Weiss (1977)

  18. Absorbency of Superabsorbent Polymers in Cementitious Environments

    DEFF Research Database (Denmark)

    Esteves, Luis Pedro; Jensen, Ole Mejlhede

    2012-01-01

    Optimal use of superabsorbent polymers (SAP) in cement-based materials relies on knowledge on how SAP absorbency is influenced by different physical and chemical parameters. These parameters include salt concentration in the pore fluid, temperature of the system and SAP particle size. The present...... work shows experimental results on this and presents a new technique to measure the swelling of SAP particles. This new technique is compared with existing techniques that have been recently proposed for the measurement of pore fluid absorption by superabsorbent polymers. It is seen...

  19. Exposure testing of solar absorber surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Moore, S.W.

    1986-01-01

    The Los Alamos National Laboratory has been involved in supporting, monitoring and conducting exposure testing of solar materials for approximately ten years. The Laboratory has provided technical monitoring of the IITRI, DSET, Lockheed, and Berry contracts and has operated the Los Alamos exposure Facility for over five years. This report will outline some of the past exposure testing, the testing still in progress, and describe some of the major findings. While this report will primarily emphasize solar absorber surfaces, some of the significant findings relative to advanced glazing will be discussed.

  20. Absorbed Energy in Ship Collisions and Grounding

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1998-01-01

    Minorsky's well-known empirical formula, which relates the absorbed energy to the destroyed material volume, has been widely used in analyses of high energy collision and grounding accidents for nearly 40 years. The advantage of the method is its apparent simplcity. Obviously, its drawback...... collisions and grounding. The developed expressions reflect the structural arrangement, the material properties and different damage patterns.The present method is validated against a large number of existing experimental results and detailed numerical simulation results. Applications to full-sale ship...

  1. The construction of normal expectations

    DEFF Research Database (Denmark)

    Quitzau, Maj-Britt; Røpke, Inge

    2008-01-01

    The gradual upward changes of standards in normal everyday life have significant environmental implications, and it is therefore important to study how these changes come about. The intention of the article is to analyze the social construction of normal expectations through a case study. The case...... concerns the present boom in bathroom renovations in Denmark, which offers an excellent opportunity to study the interplay between a wide variety of consumption drivers and social changes pointing toward long-term changes of normal expectations regarding bathroom standards. The study is problemoriented......, and the increased focus on body care and fitness. The contours of the emerging normal expectations are outlined and discussed in an environmental perspective....

  2. Consumer's inflation expectations in Brazil

    Directory of Open Access Journals (Sweden)

    Fernando Ormonde Teixeira

    Full Text Available Abstract This paper investigates what are the main components of consumer's inflation expectations. We combine the FGV's Consumer Survey with the indices of inflation (IPCA and government regulated prices, professional forecasts disclosed in the Focus report, and media data which we crawl from one of the biggest and most important Brazilian newspapers, Folha de São Paulo, to determine what factors are responsible for and improve consumer's forecast accuracy. We found gender, age and city of residence as major elements when analyzing micro-data. Aggregate data shows the past inflation as an important trigger in the formation of consumers' expectations and professional forecasts as negligible. Moreover, the media plays a significant role, accounting not only for the expectations' formation but for a better understanding of actual inflation as well.

  3. Expectations for a scientific collaboratory

    DEFF Research Database (Denmark)

    Sonnenwald, Diane H.

    2003-01-01

    with respect to scientific collaboratories. Interviews were conducted with 17 scientists who work in a variety of settings and have a range of experience conducting and managing scientific research. Results indicate that scientists expect a collaboratory to: support their strategic plans; facilitate management......In the past decade, a number of scientific collaboratories have emerged, yet adoption of scientific collaboratories remains limited. Meeting expectations is one factor that influences adoption of innovations, including scientific collaboratories. This paper investigates expectations scientists have...... of the scientific process; have a positive or neutral impact on scientific outcomes; provide advantages and disadvantages for scientific task execution; and provide personal conveniences when collaborating across distances. These results both confirm existing knowledge and raise new issues for the design...

  4. Effects of Absorber Emissivity on Thermal Performance of a Solar Cavity Receiver

    Directory of Open Access Journals (Sweden)

    Jiabin Fang

    2014-01-01

    Full Text Available Solar cavity receiver is a key component to realize the light-heat conversion in tower-type solar power system. It usually has an aperture for concentrated sunlight coming in, and the heat loss is unavoidable because of this aperture. Generally, in order to improve the thermal efficiency, a layer of coating having high absorptivity for sunlight would be covered on the surface of the absorber tubes inside the cavity receiver. As a result, it is necessary to investigate the effects of the emissivity of absorber tubes on the thermal performance of the receiver. In the present work, the thermal performances of the receiver with different absorber emissivity were numerically simulated. The results showed that the thermal efficiency increases and the total heat loss decreases with increasing emissivity of absorber tubes. However, the thermal efficiency increases by only 1.6% when the emissivity of tubes varies from 0.2 to 0.8. Therefore, the change of absorber emissivity has slight effect on the thermal performance of the receiver. The reason for variation tendency of performance curves was also carefully analyzed. It was found that the temperature reduction of the cavity walls causes the decrease of the radiative heat loss and the convective heat loss.

  5. Preliminary Nuclear Analysis for the HANARO Fuel Element with Burnable Absorber

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Chul Gyo; Kim, So Young; In, Won Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    Burnable absorber is used for reducing reactivity swing and power peaking in high performance research reactors. Development of the HANARO fuel element with burnable absorber was started in the U-Mo fuel development program at HANARO, but detailed full core analysis was not performed because the current HANARO fuel management system is uncertain to analysis the HANARO core with burnable absorber. A sophisticated reactor physics system is required to analysis the core. The McCARD code was selected and the detailed McCARD core models, in which the basic HANARO core model was developed by one of the McCARD developers, are used in this study. The development of nuclear fuel requires a long time and correct developing direction especially by the nuclear analysis. This paper presents a preliminary nuclear analysis to promote the fuel development. Based on the developed fuel, the further nuclear analysis will improve reactor performance and safety. Basic nuclear analysis for the HANARO and the AHR were performed for getting the proper fuel elements with burnable absorber. Addition of 0.3 - 0.4% Cd to the fuel meat is promising for the current HANARO fuel element. Small addition of burnable absorber may not change any fuel characteristics of the HANARO fuel element, but various basic tests and irradiation tests at the HANARO core are required.

  6. Testing and evaluation of absorbers for gaseous penetrative forms of radioiodine

    International Nuclear Information System (INIS)

    Kabot, M.

    1974-10-01

    A significant fraction of airborne radioiodine, encountered at times in operational areas of Ontario Hydro nuclear power generating stations, was found to be penetrative inorganic and organic species. Theorectical evaluation of iodine chemistry is presented based on analysis of operational iodine concentrations in station systems, areas and effluents under actual operating conditions. The theoretical evaluation and the operational experiments show that hypoiodous acid and organic iodides are the basic forms of airborne iodine which occur in the field and in station effluents. A method was developed for laboratory generation of HOI and its identity confirmed by use of specific absorbers. Six of the commercially available (and recently developed) absorbers were tested for HOI removal efficiency in the laboratory under conditions similar to those found in the field. Experimental equipment, methods used for the absorber testing and experimental conditions are described. Results show that charcoals have generally better initial absorption efficiency for hypoiodous acid than silver impregnated inorganic absorbers. Both technical and economical aspects of the operational use of the tested absorbers are discussed. (auth)

  7. A reduced-boron OPR1000 core based on the BigT burnable absorber

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hwan Yeal; Yahya, Mohd-Syukri; Kim, Yong Hee [Dept. of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon (Korea, Republic of)

    2016-04-15

    Reducing critical boron concentration in a commercial pressurized water reactor core offers many advantages in view of safety and economics. This paper presents a preliminary investigation of a reduced-boron pressurized water reactor core to achieve a clearly negative moderator temperature coefficient at hot zero power using the newly-proposed 'Burnable absorber-Integrated Guide Thimble' (BigT) absorbers. The reference core is based on a commercial OPR1000 equilibrium configuration. The reduced-boron ORP1000 configuration was determined by simply replacing commercial gadolinia-based burnable absorbers with the optimized BigT-loaded design. The equilibrium cores in this study were directly searched via repetitive Monte Carlo depletion calculations until convergence. The results demonstrate that, with the same fuel management scheme as in the reference core, application of the BigT absorbers can effectively reduce the critical boron concentration at the beginning of cycle by about 65 ppm. More crucially, the analyses indicate promising potential of the reduced-boron OPR1000 core with the BigT absorbers, as its moderator temperature coefficient at the beginning of cycle is clearly more negative and all other vital neutronic parameters are within practical safety limits. All simulations were completed using the Monte Carlo Serpent code with the ENDF/B-VII.0 library.

  8. A Reduced-Boron OPR1000 Core Based on the BigT Burnable Absorber

    Directory of Open Access Journals (Sweden)

    Hwanyeal Yu

    2016-04-01

    Full Text Available Reducing critical boron concentration in a commercial pressurized water reactor core offers many advantages in view of safety and economics. This paper presents a preliminary investigation of a reduced-boron pressurized water reactor core to achieve a clearly negative moderator temperature coefficient at hot zero power using the newly-proposed “Burnable absorber-Integrated Guide Thimble” (BigT absorbers. The reference core is based on a commercial OPR1000 equilibrium configuration. The reduced-boron ORP1000 configuration was determined by simply replacing commercial gadolinia-based burnable absorbers with the optimized BigT-loaded design. The equilibrium cores in this study were directly searched via repetitive Monte Carlo depletion calculations until convergence. The results demonstrate that, with the same fuel management scheme as in the reference core, application of the BigT absorbers can effectively reduce the critical boron concentration at the beginning of cycle by about 65 ppm. More crucially, the analyses indicate promising potential of the reduced-boron OPR1000 core with the BigT absorbers, as its moderator temperature coefficient at the beginning of cycle is clearly more negative and all other vital neutronic parameters are within practical safety limits. All simulations were completed using the Monte Carlo Serpent code with the ENDF/B-VII.0 library.

  9. Erbium concentration dependent absorbance in tellurite glass

    Energy Technology Data Exchange (ETDEWEB)

    Sazali, E. S., E-mail: mdsupar@utm; Rohani, M. S., E-mail: mdsupar@utm; Sahar, M. R., E-mail: mdsupar@utm; Arifin, R., E-mail: mdsupar@utm; Ghoshal, S. K., E-mail: mdsupar@utm; Hamzah, K., E-mail: mdsupar@utm [Advanced Optical Material Research Group, Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310, Skudai, Johor Bahru, Johor (Malaysia)

    2014-09-25

    Enhancing the optical absorption cross-section in topically important rare earth doped tellurite glasses is challenging for photonic devices. Controlled synthesis and detailed characterizations of the optical properties of these glasses are important for the optimization. The influence of varying concentration of Er{sup 3+} ions on the absorbance characteristics of lead tellurite glasses synthesized via melt-quenching technique are investigated. The UV-Vis absorption spectra exhibits six prominent peaks centered at 490, 526, 652, 800, 982 and 1520 nm ascribed to the transitions in erbium ion from the ground state to the excited states {sup 4}F{sub 7/2}, {sup 2}H{sub 11/2}, {sup 4}F{sub 9/2}, {sup 4}I{sub 9/2}, {sup 2}H{sub 11/2} and {sup 4}I{sub 13/2}, respectively. The results are analyzed by means of optical band gap E{sub g} and Urbach energy E{sub u}. The values of the energy band gap are found decreased from 2.82 to 2.51 eV and the Urbach energy increased from 0.15 to 0.24 eV with the increase of the Er{sub 2}O{sub 3} concentration from 0 to 1.5 mol%. The excellent absorbance of the prepared tellurite glasses makes them suitable for fabricating solid state lasers.

  10. Pregnant woman mode for absorbed fraction calculations

    International Nuclear Information System (INIS)

    Cloutier, R.J.; Snyder, W.S.; Watson, E.E.

    1977-01-01

    The most radiation-sensitive segment of our population is the developing fetus. Until recently, methods available for calculating the dose to the fetus were inadequate because a model for the pregnant woman was not available. Instead, the Snyder and Fisher model of Reference Man, which includes a uterus, was frequently used to calculate absorbed fractions when the source was in various organs of the body and the nongravid uterus was the target. These values would be representative of the dose to the embryo during the early stages of pregnancy. Unfortunately, Reference Man is considerable larger than Reference Woman. The authors recently reported on the design of a Reference Woman phantom that has dimensions quite similar to the ICRP Reference Woman. This phantom was suitable for calculating the dose to the embryo during early stages of pregnancy (0 to 3 mo.), but was not suitable for the later stages of pregnancy because of the changing shape of the mother and the displacement of several abdominal organs brought about by the growth of the uterus and fetus. The models of Reference Woman that were subsequently developed for each month of pregnancy are described. The models take into account the growth of the uterus and fetus and the repositioning of the various abdominal organs. These models have been used to calculate absorbed fractions for the fetus as a target and the gastrointestinal tract as a source of radiation for twelve photon energies ranging from 10 keV to 4 MeV

  11. High-efficiency ventilated metamaterial absorber at low frequency

    Science.gov (United States)

    Wu, Xiaoxiao; Au-Yeung, Ka Yan; Li, Xin; Roberts, Robert Christopher; Tian, Jingxuan; Hu, Chuandeng; Huang, Yingzhou; Wang, Shuxia; Yang, Zhiyu; Wen, Weijia

    2018-03-01

    We demonstrate a ventilated metamaterial absorber operating at low frequency (90%) has been achieved in both simulations and experiments. This high-efficiency absorption under the ventilation condition originates from the weak coupling of two identical split tube resonators constituting the absorber, which leads to the hybridization of the degenerate eigenmodes and breaks the absorption upper limit of 50% for conventional transmissive symmetric acoustic absorbers. The absorber can also be extended to an array and work in free space. The absorber should have potential applications in acoustic engineering where both noise reduction and ventilation are required.

  12. Graphene metamaterials based tunable terahertz absorber: effective surface conductivity approach

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Lavrinenko, Andrei

    2013-01-01

    In this paper we present the efficient design of functional thin-film metamaterial devices with the effective surface conductivity approach. As an example, we demonstrate a graphene based perfect absorber. After formulating the requirements to the perfect absorber in terms of surface conductivity...... we investigate the properties of graphene wire medium and graphene fishnet metamaterials and demonstrate both narrowband and broadband tunable absorbers.......In this paper we present the efficient design of functional thin-film metamaterial devices with the effective surface conductivity approach. As an example, we demonstrate a graphene based perfect absorber. After formulating the requirements to the perfect absorber in terms of surface conductivity...

  13. Self-Averaging Expectation Propagation

    DEFF Research Database (Denmark)

    Cakmak, Burak; Opper, Manfred; Fleury, Bernard Henri

    We investigate the problem of approximate inference using Expectation Propagation (EP) for large systems under some statistical assumptions. Our approach tries to overcome the numerical bottleneck of EP caused by the inversion of large matrices. Assuming that the measurement matrices are realizat...... on a signal recovery problem of compressed sensing and compare with standard EP....

  14. Expected utility with lower probabilities

    DEFF Research Database (Denmark)

    Hendon, Ebbe; Jacobsen, Hans Jørgen; Sloth, Birgitte

    1994-01-01

    An uncertain and not just risky situation may be modeled using so-called belief functions assigning lower probabilities to subsets of outcomes. In this article we extend the von Neumann-Morgenstern expected utility theory from probability measures to belief functions. We use this theory...

  15. Privacy Expectations in Online Contexts

    Science.gov (United States)

    Pure, Rebekah Abigail

    2013-01-01

    Advances in digital networked communication technology over the last two decades have brought the issue of personal privacy into sharper focus within contemporary public discourse. In this dissertation, I explain the Fourth Amendment and the role that privacy expectations play in the constitutional protection of personal privacy generally, and…

  16. Primary expectations of secondary metabolites

    Science.gov (United States)

    My program examines the plant secondary metabolites (i.e. phenolics) important for human health, and which impart the organoleptic properties that are quality indicators for fresh and processed foods. Consumer expectations such as appearance, taste, or texture influence their purchasing decisions; a...

  17. Metaphors As Storehouses of Expectation.

    Science.gov (United States)

    Beavis, Allan K.; Thomas, A. Ross

    1996-01-01

    Explores how metaphors are used to identify and store some expectations that structure schools' interactions and communications. Outlines a systems-theoretical view of schools derived from Niklas Luhmann's social theories. Illustrates how the metaphors identified in an earlier study provide material contexts for identifying and storing structures…

  18. Life Expectancy of Kibbutz Members.

    Science.gov (United States)

    Leviatan, Uri; And Others

    1986-01-01

    Data are presented demonstrating that the life expectancy of kibbutz members--both men and women--is higher than that of the overall Jewish population in Israel. These data add to and support other research findings illustrating the more positive mental health and well-being found among kibbutz members than among other comparative populations.…

  19. Gompertz-Makeham Life Expectancies

    DEFF Research Database (Denmark)

    Missov, Trifon I.; Lenart, Adam; Vaupel, James W.

    We study the Gompertz and Gompertz-Makeham mortality models. We prove that the resulting life expectancy can be expressed in terms of a hypergeometric function if the population is heterogeneous with gamma-distributed individual frailty, or an incomplete gamma function if the study population...

  20. Mechanically Robust, Stretchable Solar Absorbers with Submicron-Thick Multilayer Sheets for Wearable and Energy Applications.

    Science.gov (United States)

    Lee, Hye Jin; Jung, Dae-Han; Kil, Tae-Hyeon; Kim, Sang Hyeon; Lee, Ki-Suk; Baek, Seung-Hyub; Choi, Won Jun; Baik, Jeong Min

    2017-05-31

    A facile method to fabricate a mechanically robust, stretchable solar absorber for stretchable heat generation and an enhanced thermoelectric generator (TEG) is demonstrated. This strategy is very simple: it uses a multilayer film made of titanium and magnesium fluoride optimized by a two-dimensional finite element frequency-domain simulation, followed by the application of mechanical stresses such as bending and stretching to the film. This process produces many microsized sheets with submicron thickness (∼500 nm), showing great adhesion to any substrates such as fabrics and polydimethylsiloxane. It exhibits a quite high light absorption of approximately 85% over a wavelength range of 0.2-4.0 μm. Under 1 sun illumination, the solar absorber on various stretchable substrates increased the substrate temperature to approximately 60 °C, irrespective of various mechanical stresses such as bending, stretching, rubbing, and even washing. The TEG with the absorber on the top surface also showed an enhanced output power of 60%, compared with that without the absorber. With an incident solar radiation flux of 38.3 kW/m 2 , the output power significantly increased to 24 mW/cm 2 because of the increase in the surface temperature to 141 °C.

  1. SU-F-207-05: Excess Heat Corrections in a Prototype Calorimeter for Direct Realization of CT Absorbed Dose to Phantom

    International Nuclear Information System (INIS)

    Chen-Mayer, H; Tosh, R

    2015-01-01

    Purpose: To reconcile air kerma and calorimetry measurements in a prototype calorimeter for obtaining absorbed dose in diagnostic CT beams. While corrections for thermal artifacts are routine and generally small in calorimetry of radiotherapy beams, large differences in relative stopping powers of calorimeter materials at the lower energies typical of CT beams greatly magnify their effects. Work-to-date on the problem attempts to reconcile laboratory measurements with modeling output from Monte Carlo and finite-element analysis of heat transfer. Methods: Small thermistor beads were embedded in a polystyrene (PS) core element of 1 cm diameter, which was inserted into a cylindrical HDPE phantom of 30 cm diameter and subjected to radiation in a diagnostic CT x-ray imaging system. Resistance changes in the thermistors due to radiation heating were monitored via lock-in amplifier. Multiple 3-second exposures were recorded at 8 different dose-rates from the CT system, and least-squares fits to experimental data were compared to an expected thermal response obtained by finite-element analysis incorporating source terms based on semi-empirical modeling and Monte Carlo simulation. Results: Experimental waveforms exhibited large thermal artifacts with fast time constants, associated with excess heat in wires and glass, and smaller steps attributable to radiation heating of the core material. Preliminary finite-element analysis follows the transient component of the signal qualitatively, but predicts a slower decay of temperature spikes. This was supplemented by non-linear least-squares fits incorporating semi-empirical formulae for heat transfer, which were used to obtain dose-to-PS in reasonable agreement with the output of Monte Carlo calculations that converts air kerma to absorbed dose. Conclusion: Discrepancies between the finite-element analysis and our experimental data testify to the very significant heat transfer correction required for absorbed dose calorimetry of

  2. Critical experiments on an enriched uranium solution system containing periodically distributed strong thermal neutron absorbers

    International Nuclear Information System (INIS)

    Rothe, R.E.

    1996-01-01

    A series of 62 critical and critical approach experiments were performed to evaluate a possible novel means of storing large volumes of fissile solution in a critically safe configuration. This study is intended to increase safety and economy through use of such a system in commercial plants which handle fissionable materials in liquid form. The fissile solution's concentration may equal or slightly exceed the minimum-critical-volume concentration; and experiments were performed for high-enriched uranium solution. Results should be generally applicable in a wide variety of plant situations. The method is called the 'Poisoned Tube Tank' because strong neutron absorbers (neutron poisons) are placed inside periodically spaced stainless steel tubes which separate absorber material from solution, keeping the former free of contamination. Eight absorbers are investigated. Both square and triangular pitched lattice patterns are studied. Ancillary topics which closely model typical plant situations are also reported. They include the effect of removing small bundles of absorbers as might occur during inspections in a production plant. Not taking the tank out of service for these inspections would be an economic advantage. Another ancillary topic studies the effect of the presence of a significant volume of unpoisoned solution close to the Poisoned Tube Tank on the critical height. A summary of the experimental findings is that boron compounds were excellent absorbers, as expected. This was true for granular materials such as Gerstley Borate and Borax; but it was also true for the flexible solid composed of boron carbide and rubber, even though only thin sheets were used. Experiments with small bundles of absorbers intentionally removed reveal that quite reasonable tanks could be constructed that would allow a few tubes at a time to be removed from the tank for inspection without removing the tank from production service

  3. Absorber Alignment Measurement Tool for Solar Parabolic Trough Collectors: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Stynes, J. K.; Ihas, B.

    2012-04-01

    As we pursue efforts to lower the capital and installation costs of parabolic trough solar collectors, it is essential to maintain high optical performance. While there are many optical tools available to measure the reflector slope errors of parabolic trough solar collectors, there are few tools to measure the absorber alignment. A new method is presented here to measure the absorber alignment in two dimensions to within 0.5 cm. The absorber alignment is measured using a digital camera and four photogrammetric targets. Physical contact with the receiver absorber or glass is not necessary. The alignment of the absorber is measured along its full length so that sagging of the absorber can be quantified with this technique. The resulting absorber alignment measurement provides critical information required to accurately determine the intercept factor of a collector.

  4. Neutron Absorbing Ability Variation in Neutron Absorbing Material Caused by the Neutron Irradiation in Spent Fuel Storage Facility

    International Nuclear Information System (INIS)

    Sohn, Hee Dong; Han, Seul Gi; Lee, Sang Dong; Kim, Ki Hong; Ryu, Eag Hyang; Park, Hwa Gyu

    2014-01-01

    In spent fuel storage facility like high density spent fuel storage racks and dry storage casks, spent fuels are stored with neutron absorbing materials installed as a part of those facilities, and they are used for absorbing neutrons emitted from spent fuels. Usually structural material with neutron absorbing material of racks and casks are located around spent fuels, so it is irradiated by neutrons for long time. Neutron absorbing ability could be changed by the variation of nuclide composition in neutron absorbing material caused by the irradiation of neutrons. So, neutron absorbing materials are continuously faced with spent fuels with boric acid solution or inert gas environment. Major nuclides in neutron absorbing material are Al 27 , C 12 , B 11 , B 10 and they are changed to numerous other ones as radioactive decay or neutron absorption reaction. The B 10 content in neutron absorbing material dominates the neutron absorbing ability, so, the variation of nuclide composition including the decrease of B 10 content is the critical factor on neutron absorbing ability. In this study, neutron flux in spent fuel, the activation of neutron absorbing material and the variation of nuclide composition are calculated. And, the minimum neutron flux causing the decrease of B 10 content is calculated in spent fuel storage facility. Finally, the variation of neutron multiplication factor is identified according to the one of B 10 content in neutron absorbing material. The minimum neutron flux to impact the neutron absorbing ability is 10 10 order, however, usual neutron flux from spent fuel is 10 8 order. Therefore, even though neutron absorbing material is irradiated for over 40 years, B 10 content is little decreased, so, initial neutron absorbing ability could be kept continuously

  5. Thermoelectric System Absorbing Waste Heat from a Steel Ladle

    Science.gov (United States)

    Lu, Baiyi; Meng, Xiangning; Zhu, Miaoyong; Suzuki, Ryosuke O.

    2018-01-01

    China's iron and steel industry has made great progress in energy savings and emission reductions with the application of many waste heat recovery technologies. However, most of the medium and low temperature waste heat and radiant waste heat has not been effectively utilized. This paper proposes a thermoelectric system that generates electricity by absorbing the radiant heat from the surface of steel ladles in a steel plant. The thermoelectric behavior of modules in this system is analyzed by a numerical simulation method. The effects of external resistance and module structure on thermoelectric performance are also discussed in the temperature range of the wall surface of a steel ladle. The results show that the wall temperature has a significant influence on the thermoelectric behavior of the module, so its uniformity and stability should be considered in practical application. The ratio of the optimum external resistance to the internal resistance of the thermoelectric module is in the range of 1.6-2.0, which indicates the importance of external load optimization for a given thermoelectric system. In addition, the output power and the conversion efficiency of the module can be significantly improved by increasing the length of the thermoelectric legs and adopting a double-layer structure. Finally, through the optimization of external resistance and structure, the power output can reach 83-304 W/m2. This system is shown to be a promising approach for energy recovery.

  6. Selection and characterization of new absorbents for carbon dioxide capture

    Energy Technology Data Exchange (ETDEWEB)

    Ma' mun, Sholeh

    2005-09-01

    Removal of acidic gases, in particular CO2, is an important industrial operation. Carbon dioxide is produced in large quantities by fossil-fuel-fired power plants, steel production, the production of petrochemicals, cement production, and natural gas purification. The global climate change, where CO2 is found to be a major contributor, is one of the most important and challenging environmental issues facing the world community. This has motivated intensive research on CO2 capture and storage. Carbon dioxide capture by an absorption process is one of the most common industrial technologies today. Recent economic studies indicate that the process will also remain competitive in the future. One of the key improvements under development is new, faster and more energy-efficient absorbents. A chemical to be used as a commercial absorbent must have high net cyclic capacity, high absorption rate for CO2 and good chemical stability. Alkanolamines are the most commonly used chemical absorbents for the removal of acidic gases today. In the first part of this thesis, an experimental screening of new absorbents for CO2 capture was performed by absorption of CO2 into both single absorbents and absorbent mixtures for amine-based and non-amine-based systems at 40 deg. Celsius From testing of approx. 30 systems, it was found that an aqueous 30 mass % AEEA (2-(2-aminoethyl-amino)ethanol) solution seems to be a potentially good absorbent for capturing CO2 from atmospheric flue gases. It offers high absorption rate combined with high absorption capacity. In addition toAEEA, MMEA (2-(methylamino)ethanol) also needs to be considered. It could have a good potential when used in contactors where the two phases are separated, like in membrane contactors, whereas indications from the study showed foaming tendencies that will make it difficult to use in ordinary towers. AEEA as the selected absorbent obtained from the screening tests was further investigated to determine its vapor

  7. Microwave absorbing property of a hybrid absorbent with carbonyl irons coating on the graphite

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yonggang, E-mail: xuyonggang221@163.com [Science and Technology on Electromagnetic Scattering Laboratory, Shanghai, 200438 (China); Yan, Zhenqiang; Zhang, Deyuan [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China)

    2015-11-30

    Graphical abstract: The absorbing property could be enhanced as the CIPs coated on the graphite. - Highlights: • Absorbers filled with CIPs coating on the graphite was fabricated. • The permittivity and permeability increased as CIPs coated. • The CIP materials enhanced the electromagnetic property. • The graphite coated CIPs were effective in 2–18 GHz. - Abstract: The hybrid absorbent filled with carbonyl iron particles (CIPs) coating on the graphite was prepared using a chemical vapor decomposition (CVD) process. X-ray diffraction (XRD) patterns were done to analyze the particle crystal grain structure. The complex permittivity and permeability were measured using a vector network analyzer in the frequency range of 2–18 GHz. The results showed that α-Fe appeared in the super-lattice diffraction peaks in XRD graph. The composites added CIPs coating on the graphite had a higher permittivity and imaginary permeability due to the superior microwave dielectric loss and magnetic loss of the CIPs. The reflection loss (RL) result showed that composites filled with 5 vol% Fe-graphite had an excellent absorbing property in the 2–18 GHz, the minimum RL was −25.14 dB at 6 mm and −26.52 dB at 8 mm, respectively.

  8. Ethical issues and societal expectations

    International Nuclear Information System (INIS)

    Metlay, D.

    2010-01-01

    Daniel Metlay (NWTRB) declared that institutions had always recognised an ethical obligation to manage high- level radioactive waste in unprecedented ways. This obligation has not only endured, but has become more explicit and multidimensional and it now subsumed under a more general rubric of 'societal expectations'. D. Metlay directed attention toward the proceedings of previous RWMC-RF workshop ', which contains five essays, authored by Kjell Andersson, Andrew Blowers, Carl-Reinhold Braakenhielm, Francois Dermange, and Patricia Fleming, that are relevant to the question of ethical issues and societal expectations. D. Metlay observed that 'societal expectations' are hard to define and thus very hard to measure. They may vary considerably with time and from country to country. As an illustration he referred to an inquiry performed by a task group 30 years ago in a document entitled 'Proposed Goals for Radioactive Waste Management' (NUREG-0300) on behalf of the U.S. Nuclear Regulatory Commission. Conclusions from D. Metlay are that, for the most part, societal expectations in the United States appear to be quite stable over a period of more than 30 years. In two areas, however, there are clear differences in emphasis between expectations articulated in the last few years and those recorded in 1978. (1) While then there was emphasis on the operational reliability of organisations and institutions. In particular, much care was taken to discuss the inherent limitations on bureaucratic error-correction in the future. The focus is nowadays more on bureaucratic behaviours associated with carrying out decision-making processes in the present. (2) While there is current emphasis on the importance of trust, transparency, and accountability, the NRC document may cast some doubt on the reliability of a stepwise decision-making process. In the domain of radioactive waste management, error signals are notoriously unclear, and strong disagreements over objectives and value trade

  9. Misconceptions and false expectations in neutral evolution

    Directory of Open Access Journals (Sweden)

    CARLOS Y. VALENZUELA

    2000-01-01

    Full Text Available Neutral evolution results from random recurrent mutation and genetic drift. A small part of random evolution, that which is related to protein or DNA polymorphisms, is the subject of the Neutral Theory of Evolution. One of the foundations of this theory is the demonstration that the mutation rate (m is equal to the substitution rate. Since both rates are independent of population size, they are independent of drift, which is dependent upon population size. Neutralists have erroneously equated the substitution rate with the fixation rate, despite the fact that they are antithetical conceptions. The neutralists then applied the random walk stochastic model to justify alleles or bases that were fixated or eliminated. In this model, once the allele or base frequencies reach the monomorphic states (values of 1.0 or 0.0, the absorbing barriers, they can no longer return to the polymorphic state. This operates in a pure mathematical model. If recurrent mutation occurs (as in biotic real systems fixation and elimination are impossible. A population of bacteria in which m=10-8 base mutation (or substitution/site/generation and the reproduction rate is 1000 cell cycle/year should replace all its genome bases in approximately 100,000 years. The expected situation for all sites is polymorphism for the four bases rather than monomorphism at 1.0 or 0.0 frequencies. If fixation and elimination of a base for more than 500,000 years are impossible, then most of the neutral theory is untenable. A new complete neutral model, which allows for recurrent substitutions, is proposed here based on recurrent mutation or substitution and drift alone. The model fits a binomial or Poisson distribution and not a geometric one, as does neutral theory.

  10. A chiral microwave absorbing absorbent of Fe–CoNiP coated on spirulina

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yonggang, E-mail: xuyonggang221@163.com [Science and Technology on Electromagnetic Scattering Laboratory, Shanghai, 200438 (China); Yuan, Liming [Science and Technology on Electromagnetic Scattering Laboratory, Shanghai, 200438 (China); Zhang, Deyuan [School of Mechanical Engineering and Automation, Beihang University, Beijing, 100191 (China)

    2015-11-15

    A chiral bio-absorbent of Fe–CoNiP coated on the spirulina was fabricated by the electroless and chemical vapor decomposition. The scanning electron microscopy (SEM) was used to evaluate the spirulina cells particle morphology. X-ray diffraction (XRD) patterns were done to analyze the particle crystal grain structure. The permittivity and permeability was measured by a vector network analyzer in frequency 8–18 GHz, and the reflection loss (RL) was calculated. The results showed the carbonyl iron particles (CIPs) and CoNiP were bonded to the spirulina surface, the permittivity and permeability could be enlarged as Fe films coated on the particles compared with the CoNiP spirulina, it was attributed to the excellent electromagnetic property of CIPs. The chiral Fe–CoNiP composites had a better absorbing property at 8–18 GHz than the CoNiP spirulina composite, the RL was −16.26 dB at 10.48 GHz, the absorbing band was 9.5–11.5 GHz of RL less than −10 dB, which indicated the Fe–CoNiP spirulina could be an effective absorbent used in 8–18 GHz. - Highlights: • Absorbers filled with Fe–CoNiP coating on the spirulina were fabricated. • The permittivity and permeability increased as CIPs coated. • The Fe material enhanced the electromagnetic property. • The spirulina coated Fe–CoNiP was effective in 8–18 GHz.

  11. Using expected localization in segmentation

    Science.gov (United States)

    Shemlon, Stephen; Cho, Kyugon; Dunn, Stanley M.

    1992-02-01

    Segmentation paradigms are based on manipulating some distinguishing characteristic of the various objects that are present in the image being analyzed. These characteristics are often well known for given objects in a given class of images. The intelligent use of this knowledge can simplify the segmentation process without necessarily targeting it for a particular class of images. This paper outlines a segmentation paradigm that uses models which characterize the expected presentation of possible image objects. It explains how knowledge of the expected localization of certain objects can be used to refine the segmentation process, to optimize object extraction and identification, and to learn some invariant characteristics of the objects and their surroundings, for use by high level intelligent processes. We present results of experiments with MRI human brain scans, dental radiographs, and transmission electron microscope (TEM) serial sections of hemocytes (insect blood cells).

  12. Extrapolative Expectations and Market Stability.

    OpenAIRE

    Vega-Redondo, Fernando

    1989-01-01

    An auctioneer model of market adjustment is proposed which, unlike the standard formulation, has prices react to extrapolated (rather than prevailing) excess demands. If expectations are sufficiently sensitive to current rates of change, every regular market equilibrium is shown to be locally stable. The model can be regarded as providing an institutional interpretation to Newton-like methods of market adjustment that, as the Newton process itself, ensure stability of every regular zero of a ...

  13. Smooth paths of conditional expectations

    OpenAIRE

    Andruchow, Esteban; Larotonda, Gabriel

    2010-01-01

    Let A be a von Neumann algebra with a finite trace $\\tau$, represented in $H=L^2(A,\\tau)$, and let $B_t\\subset A$ be sub-algebras, for $t$ in an interval $I$. Let $E_t:A\\to B_t$ be the unique $\\tau$-preserving conditional expectation. We say that the path $t\\mapsto E_t$ is smooth if for every $a\\in A$ and $v \\in H$, the map $$ I\

  14. FRANCHISE EXPECTATIONS: CASE OF KAZAKHSTAN

    OpenAIRE

    Raissa Kaziyeva

    2014-01-01

    The purpose of the article is to provide a critical review of franchising development in Kazakhstan by focusing on the relationship between the franchisor and the franchisee. We have conducted extensive research and communicated with lots of potential and existing Kazakhstani franchisors and franchisees, operating since 2003. Our findings show that the process of signing franchising agreements is quite challenging in Kazakhstan.  Thorough investigation of the differences between expectations ...

  15. Corundum-based transparent infrared absorbers

    KAUST Repository

    Schwingenschlögl, Udo

    2009-10-01

    Hypothetical corundum-based compounds are studied by electronic structure calculations. One quarter of the Al atoms in Al2O3 is replaced by a 3d transition metal from the M = Ti, ..., Zn (d1, ..., d9) series. Structure optimisations are performed for all the M-Al2O3 compounds and the electronic states are evaluated. Due to the M substitutes, narrow partially filled bands are formed at the Fermi energy. Beyond, for M = Ni and M = Cu the optical properties of Al2O3 in the visible range are conserved, while for M = Ti, ..., Co the systems form high accuracy optical filters. Since the compounds absorb the infrared radiation, the M = Ni and M = Cu systems are good candidates for heat-protective coatings. © 2009 Elsevier B.V. All rights reserved.

  16. Electromagnetic radiation absorbers and modulators comprising polyaniline

    Science.gov (United States)

    Epstein, Arthur J.; Ginder, John M.; Roe, Mitchell G.; Hajiseyedjavadi, Hamid

    1992-01-01

    A composition for absorbing electromagnetic radiation, wherein said electromagnetic radiation possesses a wavelength generally in the range of from about 1000 Angstroms to about 50 meters, wherein said composition comprises a polyaniline composition of the formula ##STR1## where y can be equal to or greater than zero, and R.sup.1 and R.sup.2 are independently selected from the group containing of H, --OCH.sub.3, --CH.sub.3, --F, --Cl, --Br, --I, NR.sup.3 .sub.2, --NHCOR.sup.3, --OH, --O.sup.-, SR.sup.3, --OCOR.sup.3, --NO.sub.2, --COOH, --COOR.sup.3, --COR.sup.3, --CHO, and --CN, where R.sup.3 is a C.sub.1 to C.sub.8 alkyl, aryl or aralkyl group.

  17. Ultrathin microwave metamaterial absorber utilizing embedded resistors

    Science.gov (United States)

    Kim, Young Ju; Hwang, Ji Sub; Yoo, Young Joon; Khuyen, Bui Xuan; Rhee, Joo Yull; Chen, Xianfeng; Lee, YoungPak

    2017-10-01

    We numerically and experimentally studied an ultrathin and broadband perfect absorber by enhancing the bandwidth with embedded resistors into the metamaterial structure, which is easy to fabricate in order to lower the Q-factor and by using multiple resonances with the patches of different sizes. We analyze the absorption mechanism in terms of the impedance matching with the free space and through the distribution of surface current at each resonance frequency. The magnetic field, induced by the antiparallel surface currents, is formed strongly in the direction opposite to the incident electromagnetic wave, to cancel the incident wave, leading to the perfect absorption. The corresponding experimental absorption was found to be higher than 97% in 0.88-3.15 GHz. The agreement between measurement and simulation was good. The aspects of our proposed structure can be applied to future electronic devices, for example, advanced noise-suppression sheets in the microwave regime.

  18. Rising Expectations, Social Unrest & Development

    Directory of Open Access Journals (Sweden)

    Ashok Natarajan

    2011-10-01

    Full Text Available The relationship between peace and development holds the key to effective strategies for addressing the roots of social unrest. Rising expectations are the principal driving force for social development. However, the faster and higher aspirations rise, the greater the gap between expectations and reality. That gap promotes a sense of frustration, depravation and aggression leading to social unrest and violence. The opposite is also true: rising economic opportunity can mitigate or eliminate social unrest. The remarkable renunciation of armed struggle by the IRA in North Ireland in mid - 2005 appears inexplicable until the impact of rising incomes and expanding employment opportunities in the Republic of Ireland is also taken into account. A similar approach can be applied to address the problems of violence and social unrest in Kashmir and Palestine. Here too apparently intractable conflicts will lend themselves to be addressed economically. India's recent efforts to provide guaranteed employment to its rural poor are part of a strategy to stem the rising tide of social unrest in impoverished areas resulting from rising expectations among the poor.

  19. Metastable neural dynamics mediates expectation

    Science.gov (United States)

    Mazzucato, Luca; La Camera, Giancarlo; Fontanini, Alfredo

    Sensory stimuli are processed faster when their presentation is expected compared to when they come as a surprise. We previously showed that, in multiple single-unit recordings from alert rat gustatory cortex, taste stimuli can be decoded faster from neural activity if preceded by a stimulus-predicting cue. However, the specific computational process mediating this anticipatory neural activity is unknown. Here, we propose a biologically plausible model based on a recurrent network of spiking neurons with clustered architecture. In the absence of stimulation, the model neural activity unfolds through sequences of metastable states, each state being a population vector of firing rates. We modeled taste stimuli and cue (the same for all stimuli) as two inputs targeting subsets of excitatory neurons. As observed in experiment, stimuli evoked specific state sequences, characterized in terms of `coding states', i.e., states occurring significantly more often for a particular stimulus. When stimulus presentation is preceded by a cue, coding states show a faster and more reliable onset, and expected stimuli can be decoded more quickly than unexpected ones. This anticipatory effect is unrelated to changes of firing rates in stimulus-selective neurons and is absent in homogeneous balanced networks, suggesting that a clustered organization is necessary to mediate the expectation of relevant events. Our results demonstrate a novel mechanism for speeding up sensory coding in cortical circuits. NIDCD K25-DC013557 (LM); NIDCD R01-DC010389 (AF); NSF IIS-1161852 (GL).

  20. Grade Expectations: Rationality and Overconfidence

    Directory of Open Access Journals (Sweden)

    Jan R. Magnus

    2018-01-01

    Full Text Available Confidence and overconfidence are essential aspects of human nature, but measuring (overconfidence is not easy. Our approach is to consider students' forecasts of their exam grades. Part of a student's grade expectation is based on the student's previous academic achievements; what remains can be interpreted as (overconfidence. Our results are based on a sample of about 500 second-year undergraduate students enrolled in a statistics course in Moscow. The course contains three exams and each student produces a forecast for each of the three exams. Our models allow us to estimate overconfidence quantitatively. Using these models we find that students' expectations are not rational and that most students are overconfident, in agreement with the general literature. Less obvious is that overconfidence helps: given the same academic achievement students with larger confidence obtain higher exam grades. Female students are less overconfident than male students, their forecasts are more rational, and they are also faster learners in the sense that they adjust their expectations more rapidly.

  1. Grade Expectations: Rationality and Overconfidence

    Science.gov (United States)

    Magnus, Jan R.; Peresetsky, Anatoly A.

    2018-01-01

    Confidence and overconfidence are essential aspects of human nature, but measuring (over)confidence is not easy. Our approach is to consider students' forecasts of their exam grades. Part of a student's grade expectation is based on the student's previous academic achievements; what remains can be interpreted as (over)confidence. Our results are based on a sample of about 500 second-year undergraduate students enrolled in a statistics course in Moscow. The course contains three exams and each student produces a forecast for each of the three exams. Our models allow us to estimate overconfidence quantitatively. Using these models we find that students' expectations are not rational and that most students are overconfident, in agreement with the general literature. Less obvious is that overconfidence helps: given the same academic achievement students with larger confidence obtain higher exam grades. Female students are less overconfident than male students, their forecasts are more rational, and they are also faster learners in the sense that they adjust their expectations more rapidly. PMID:29375449

  2. Light Absorbing Aerosols in Mexico City

    Science.gov (United States)

    Marley, N. A.; Kelley, K. L.; Kilaparty, P. S.; Gaffney, J. S.

    2008-12-01

    The direct effects of aerosol radiative forcing has been identified by the IPCC as a major uncertainty in climate modeling. The DOE Megacity Aerosol Experiment-Mexico City (MAX-Mex), as part of the MILAGRO study in March of 2006, was undertaken to reduce these uncertainties by characterization of the optical, chemical, and physical properties of atmospheric aerosols emitted from this megacity environment. Aerosol samples collected during this study using quartz filters were characterized in the uv-visible-infrared by using surface spectroscopic techniques. These included the use of an integrating sphere approach combined with the use of Kubelka-Munk theory to obtain aerosol absorption spectra. In past work black carbon has been assumed to be the only major absorbing species in atmospheric aerosols with an broad band spectral profile that follows a simple inverse wavelength dependence. Recent work has also identified a number of other absorbing species that can also add to the overall aerosol absorption. These include primary organics from biomass and trash burning and secondary organic aerosols including nitrated PAHs and humic-like substances, or HULIS. By using surface diffuse reflection spectroscopy we have also obtained spectra in the infrared that indicate significant IR absorption in the atmospheric window-region. These data will be presented and compared to spectra of model compounds that allow for evaluation of the potential importance of these species in adding strength to the direct radiative forcing of atmospheric aerosols. This work was supported by the Office of Science (BER), U.S. Department of Energy, Grant No. DE-FG02-07ER64327 as part of the Atmospheric Science Program.

  3. Neutron absorbed dose in a pacemaker CMOS

    Energy Technology Data Exchange (ETDEWEB)

    Borja H, C. G.; Guzman G, K. A.; Valero L, C. Y.; Banuelos F, A.; Hernandez D, V. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Paredes G, L., E-mail: candy_borja@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2011-11-15

    The absorbed dose due to neutrons by a Complementary Metal Oxide Semiconductor (CMOS) has been estimated using Monte Carlo methods. Eventually a person with a pacemaker becomes a patient that must be treated by radiotherapy with a linear accelerator; the pacemaker has integrated circuits as CMOS that are sensitive to intense and pulsed radiation fields. When the Linac is working in Bremsstrahlung mode an undesirable neutron field is produced due to photoneutron reactions; these neutrons could damage the CMOS putting the patient at risk during the radiotherapy treatment. In order to estimate the neutron dose in the CMOS a Monte Carlo calculation was carried out where a full radiotherapy vault room was modeled with a W-made spherical shell in whose center was located the source term of photoneutrons produced by a Linac head operating in Bremsstrahlung mode at 18 MV. In the calculations a phantom made of tissue equivalent was modeled while a beam of photoneutrons was applied on the phantom prostatic region using a field of 10 x 10 cm{sup 2}. During simulation neutrons were isotropically transported from the Linac head to the phantom chest, here a 1 {theta} x 1 cm{sup 2} cylinder made of polystyrene was modeled as the CMOS, where the neutron spectrum and the absorbed dose were estimated. Main damages to CMOS are by protons produced during neutron collisions protective cover made of H-rich materials, here the neutron spectrum that reach the CMOS was calculated showing a small peak around 0.1 MeV and a larger peak in the thermal region, both connected through epithermal neutrons. (Author)

  4. Robust non-fragile dynamic vibration absorbers with uncertain factors

    Science.gov (United States)

    Zhang, Hui; Shi, Yang; Saadat Mehr, Aryan

    2011-02-01

    In this paper, the design problem for non-fragile dynamic vibration absorbers (DVAs) is investigated. Due to the imprecision of the manufacturing process or the variation during the operation, uncertainty in the parameters of the DVA is unavoidable. The uncertainty may degrade the performance of the designed DVA or even deteriorate the system. Hence, it is practically demanding to propose a design method for a non-fragile DVA, i.e., when the parameters of the DVA vary in an admissible range, an expected vibration suppression level should be guaranteed. The uncertainty of the DVA is feasibly assumed to be norm-bounded. Then, the design problem for the DVA is converted into a static output feedback (SOF) control problem. Sufficient condition for the existence of the non-fragile DVA with a prescribed H∞ level is derived by using a bilinear matrix inequality (BMI). An iterative linear matrix inequality (ILMI) method is employed to solve the BMI condition. Finally, a design example is given to show the effectiveness of the proposed approach.

  5. Heat and mass transfer enhancement in absorbing processes

    International Nuclear Information System (INIS)

    Hijikata, Kunio; Lee, S.K.

    1993-01-01

    The key to improving the performance of absorption-type heat machines lies in the enhancement of the mass transfer of the vapor into the absorbant solution, since the mass diffusivity in the solution is very small compared to the thermal diffusivity. The absorption process is influenced by many factors including physical properties of the fluids, the flow pattern and others, especially the velocity profile near the interface is the most important. From these stand points, the heat and mass transfer in the absorption was investigated by following three steps. First, an augmentation of the absorption to a liquid film flowing in groove was theoretically investigated, in which the interface between the vapor and liquid film is cooled by the grooved surfaces. Secondly, systematical experiments were carried out on several factors that affect the absorption process, which were the cooling wall temperature, the inlet solution subcooling, and the fin configuration. Finally, a numerical study of the heat and mass transfer enhancement due to flow agitation by the periodically grooved channel was conducted. That flow realized by fabricating ridges on the fin surface. A secondary flow due to these ridges is expected to enhance the heat and mass transfer. These results were compared with experimental ones. (orig.)

  6. The technology transfer and the Laguna Verde power plants

    International Nuclear Information System (INIS)

    Garza, R.F. de La

    1991-01-01

    The process of technology transfer to the construction of Laguna Verde Nuclear Power Plants, Mexico, is described. The options and the efforts for absorbing the technology of Nuclear Power Plant design and construction by the mexican engineers are emphasized. (author)

  7. Expectations from experts in ethics

    International Nuclear Information System (INIS)

    Dermange, F.

    2008-01-01

    The aim of this paper is to try to answer the three questions raised by Claudio Pescatore. 1. When the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management requires that we do not compromise the ability of future generations to meet their needs and aspirations, what is meant by 'needs and aspirations'? 2. What are regulators expected to do to identify the needs and aspirations of the relevant future generations, and to provide convincing regulatory assurance that they will be protected? 3. How many generations ahead constitute 'future generations' for the purpose of implementing sustainable development? (author)

  8. Preparation and characterization of super absorbent polymer from sugarcane bagasse

    International Nuclear Information System (INIS)

    Wiwien Andriyanti; Suyanti; Ngasifudin

    2012-01-01

    Sugarcane bagasse is a source of biomass which large enough numbers and has not been fully exploited. At this time has developed a super absorbent polymer material of sugarcane bagasse that can absorb water up to several times of its own weight and keep this water. Super absorbent polymers can be used as a soil conditioner that can be used as an absorber and storage of ground water, the giver of nutrients for plants, and can improve soil properties. The purpose of this study is to make and characterization of super absorbent polymer (PCS) from sugarcane bagasse. Preparation of super absorbent polymers (PCS) has been done by grafting method using ionizing radiation from Electron Beam Engineering (MBE) 350 mA keV/10. Irradiation process carried out with a dose variation of 20, 35, and 50 kGy. Increasing doses of radiation will increase the percentage fraction of transplantation (grafting) and the fraction of water absorption ability (swelling ratio). (author)

  9. Giant Planets in Reflected Light: What Science Can We Expect?

    Science.gov (United States)

    Marley, Mark

    2016-01-01

    Interpreting the reflection spectra of cool giant planets will be a challenge. Spectra of such worlds are expected to be primarily shaped by scattering from clouds and hazes and punctuated by absorption bands of methane, water, and ammonia. While the warmest giants may be cloudless, their atmospheres will almost certainly sport substantial photochemical hazes. Furthermore the masses of most direct imaging targets will be constrained by radial velocity observations, their radii, and thus atmospheric gravity, will be imperfectly known. The uncertainty in planet radius and gravity will compound with uncertain aerosol properties to make estimation of key absorber abundances difficult. To address such concerns our group is developing atmospheric retrieval tools to constrain quantities of interest, particular gas mixing ratios. We have applied our Markov Chain Monte Carlo methods to simulated data of the quality expected from the WFIRST CGI instrument and found that given sufficiently high SNR data we can confidentially identify and constrain the abundance of methane, cloud top pressures, gravity, and the star-planet-observer phase angle. In my presentation I will explain the expected characteristics of cool extrasolar giant planet reflection spectra, discuss these and other challenges in their interpretation, and summarize the science results we can expect from direct imaging observations.

  10. Solids-based concentrated solar power receiver

    Energy Technology Data Exchange (ETDEWEB)

    None

    2018-04-10

    A concentrated solar power (CSP) system includes channels arranged to convey a flowing solids medium descending under gravity. The channels form a light-absorbing surface configured to absorb solar flux from a heliostat field. The channels may be independently supported, for example by suspension, and gaps between the channels are sized to accommodate thermal expansion. The light absorbing surface may be sloped so that the inside surfaces of the channels proximate to the light absorbing surface define downward-slanting channel floors, and the flowing solids medium flows along these floors. Baffles may be disposed inside the channels and oriented across the direction of descent of the flowing solids medium. The channels may include wedge-shaped walls forming the light-absorbing surface and defining multiple-reflection light paths for solar flux from the heliostat field incident on the light-absorbing surface.

  11. Local Structure Analysis of Materials for Solar Cell Absorber Layer

    OpenAIRE

    Jewell, Leila Elizabeth

    2016-01-01

    This dissertation examines solar cell absorber materials that have the potential to replace silicon in solar cells, including several copper-based sulfides and perovskites. Earth-abundant absorbers such as these become even more cost-effective when used in a nanostructured solar cell. Atomic layer deposition (ALD) and chemical vapor deposition (CVD) deposit highly conformal films and hence are important tools for developing extremely thin absorber solar cells with scalability. Thus, the prima...

  12. Tridimensional measurements of the Barrel absorbers (Module 0)

    CERN Document Server

    Puzo, P

    2001-01-01

    In this note we describe the principle of the measurements done on the ATLAS absorbers that have been fabricated for the module 0 of the Liquid Argon Electromagnetic Barrel Calorimeter. We explain how the measurements are used to reconstruct the tridimensional geometry of each absorber. We show the results obtained for module 0. The same kind of measurements will be done for the series absorbers

  13. Regulatory Expectations for Safety Culture

    International Nuclear Information System (INIS)

    Jung, Su Jin; Oh, Jang Jin; Choi, Young Sung

    2014-01-01

    The oversight of licensee's safety culture becomes an important issue that attracts great public and political concerns recently in Korea. Beginning from the intended violation of rules, a series of corruptions, documents forgery and disclosure of wrong-doings made the public think that the whole mindset of nuclear workers has been inadequate. Thus, they are demanding that safety culture shall be improved and that regulatory body shall play more roles and responsibilities for the improvements and oversight for them. This paper introduces, as an effort of regulatory side, recent changes in the role of regulators in safety culture, regulatory expectations on the desired status of licensee's safety culture, the pilot inspection program for safety culture and research activity for the development of oversight system. After the Fukushima accident in Japan 2011, many critics has searched for cultural factors that caused the unacceptable negligence pervaded in Japan nuclear society and the renewed emphasis has been placed on rebuilding safety culture by operators, regulators, and relevant institutions globally. Significant progress has been made in how to approach safety culture and led to a new perspective different from the existing normative assessment method both in operators and regulatory side. Regulatory expectations and oversight of them are based on such a new holistic concept for human, organizational and cultural elements to maintain and strengthen the integrity of defense in depth and consequently nuclear safety

  14. Regulatory Expectations for Safety Culture

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Su Jin; Oh, Jang Jin; Choi, Young Sung [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2014-05-15

    The oversight of licensee's safety culture becomes an important issue that attracts great public and political concerns recently in Korea. Beginning from the intended violation of rules, a series of corruptions, documents forgery and disclosure of wrong-doings made the public think that the whole mindset of nuclear workers has been inadequate. Thus, they are demanding that safety culture shall be improved and that regulatory body shall play more roles and responsibilities for the improvements and oversight for them. This paper introduces, as an effort of regulatory side, recent changes in the role of regulators in safety culture, regulatory expectations on the desired status of licensee's safety culture, the pilot inspection program for safety culture and research activity for the development of oversight system. After the Fukushima accident in Japan 2011, many critics has searched for cultural factors that caused the unacceptable negligence pervaded in Japan nuclear society and the renewed emphasis has been placed on rebuilding safety culture by operators, regulators, and relevant institutions globally. Significant progress has been made in how to approach safety culture and led to a new perspective different from the existing normative assessment method both in operators and regulatory side. Regulatory expectations and oversight of them are based on such a new holistic concept for human, organizational and cultural elements to maintain and strengthen the integrity of defense in depth and consequently nuclear safety.

  15. Will energy crop yields meet expectations?

    International Nuclear Information System (INIS)

    Searle, Stephanie Y.; Malins, Christopher J.

    2014-01-01

    Expectations are high for energy crops. Government policies in the United States and Europe are increasingly supporting biofuel and heat and power from cellulose, and biomass is touted as a partial solution to energy security and greenhouse gas mitigation. Here, we review the literature for yields of 5 major potential energy crops: Miscanthus spp., Panicum virgatum (switchgrass), Populus spp. (poplar), Salix spp. (willow), and Eucalyptus spp. Very high yields have been achieved for each of these types of energy crops, up to 40 t ha −1  y −1 in small, intensively managed trials. But yields are significantly lower in semi-commercial scale trials, due to biomass losses with drying, harvesting inefficiency under real world conditions, and edge effects in small plots. To avoid competition with food, energy crops should be grown on non-agricultural land, which also lowers yields. While there is potential for yield improvement for each of these crops through further research and breeding programs, for several reasons the rate of yield increase is likely to be slower than historically has been achieved for cereals; these include relatively low investment, long breeding periods, low yield response of perennial grasses to fertilizer, and inapplicability of manipulating the harvest index. Miscanthus × giganteus faces particular challenges as it is a sterile hybrid. Moderate and realistic expectations for the current and future performance of energy crops are vital to understanding the likely cost and the potential of large-scale production. - Highlights: • This review covers Miscanthus, switchgrass, poplar, willow, and Eucalyptus. • High yields of energy crops are typically from small experimental plots. • Field scale yields are lower due to real world harvesting losses and edge effects. • The potential for yield improvement of energy crops is relatively limited. • Expectations must be realistic for successful policies and commercial production

  16. Geophysical forecast: industry expects busy winter season

    Energy Technology Data Exchange (ETDEWEB)

    Ludwick, J.

    1997-11-01

    Survey results by the Canadian Association of Geophysical Contractors were discussed. According to the survey, all of the sector`s 65 crews will be fully utilized this winter, although no activity records are expected. Charges are likely to be slightly higher than last year. At least some of the increase will go towards increased pay to attract more workers into the field in an effort to counter the labour shortage in the seismic industry. Contractors must compete with other sectors such as construction, which is booming as a result of Alberta`s burgeoning economy. The Slave Lake and Rocky Mountain House regions are expected to be the hottest in Alberta. Southeastern Saskatchewan also promises to be the site of increased activity due to the growing interest in the Red River oil play. Another reason for the increased activity may be the use of innovative technology such as that employed by Enertec Geophysical Service Limited. It will pilot-test its newly acquired PowerProbe technology, which is said to be able to immediately detect the presence of hydrocarbons.

  17. The expected anisotropy in solid inflation

    Energy Technology Data Exchange (ETDEWEB)

    Bartolo, Nicola; Ricciardone, Angelo [Dipartimento di Fisica e Astronomia ' ' G. Galilei' ' , Università degli Studi di Padova, via Marzolo 8, I-35131, Padova (Italy); Peloso, Marco; Unal, Caner, E-mail: nicola.bartolo@pd.infn.it, E-mail: peloso@physics.umn.edu, E-mail: angelo.ricciardone@pd.infn.it, E-mail: unal@physics.umn.edu [School of Physics and Astronomy, University of Minnesota, 116 Church Street S.E., Minneapolis 55455 (United States)

    2014-11-01

    Solid inflation is an effective field theory of inflation in which isotropy and homogeneity are accomplished via a specific combination of anisotropic sources (three scalar fields that individually break isotropy). This results in specific observational signatures that are not found in standard models of inflation: a non-trivial angular dependence for the squeezed bispectrum, and a possibly long period of anisotropic inflation (to drive inflation, the ''solid'' must be very insensitive to any deformation, and thus background anisotropies are very slowly erased). In this paper we compute the expected level of statistical anisotropy in the power spectrum of the curvature perturbations of this model. To do so, we account for the classical background values of the three scalar fields that are generated on large (superhorizon) scales during inflation via a random walk sum, as the perturbation modes leave the horizon. Such an anisotropy is unavoidably generated, even starting from perfectly isotropic classical initial conditions. The expected level of anisotropy is related to the duration of inflation and to the amplitude of the squeezed bispectrum. If this amplitude is close to its current observational limit (so that one of the most interesting predictions of the model can be observed in the near future), we find that a level of statistical anisotropy F{sup 2} gives frozen and scale invariant vector perturbations on superhorizon scales.

  18. Power generation

    International Nuclear Information System (INIS)

    Nunez, Anibal D.

    2001-01-01

    In the second half of twentieth century, nuclear power became an industrial reality. Now the operating 433 power plants, the 37 plants under construction, near 9000 years/reactor with only one serious accident with emission of radioactive material to the environment (Chernobyl) show the maturity of this technology. Today nuclear power contribute a 17% to the global generation and an increase of 75 % of the demand of electricity is estimated for 2020 while this demand is expected to triplicate by 2050. How this requirement can be satisfied? All the indicators seems to demonstrate that nuclear power will be the solution because of the shortage of other sources, the increase of the prices of the non renewable fuels and the scarce contribution of the renewable ones. In addition, the climatic changes produced by the greenhouse effect make even more attractive nuclear power. The situation of Argentina is analyzed and compared with other countries. The convenience of an increase of nuclear power contribution to the total national generation seems clear and the conclusion of the construction of the Atucha II nuclear power plant is recommended

  19. NASA's Bio-Inspired Acoustic Absorber Concept

    Science.gov (United States)

    Koch, L. Danielle

    2017-01-01

    Transportation noise pollutes our worlds cities, suburbs, parks, and wilderness areas. NASAs fundamental research in aviation acoustics is helping to find innovative solutions to this multifaceted problem. NASA is learning from nature to develop the next generation of quiet aircraft.The number of road vehicles and airplanes has roughly tripled since the 1960s. Transportation noise is audible in nearly all the counties across the US. Noise can damage your hearing, raise your heart rate and blood pressure, disrupt your sleep, and make communication difficult. Noise pollution threatens wildlife when it prevents animals from hearing prey, predators, and mates. Noise regulations help drive industry to develop quieter aircraft. Noise standards for aircraft have been developed by the International Civil Aviation Organization and adopted by the US Federal Aviation Administration. The US National Park Service is working with the Federal Aviation Administration to try to balance the demand for access to the parks and wilderness areas with preservation of the natural soundscape. NASA is helping by conceptualizing quieter, more efficient aircraft of the future and performing the fundamental research to make these concepts a reality someday. Recently, NASA has developed synthetic structures that can absorb sound well over a wide frequency range, and particularly below 1000 Hz, and which mimic the acoustic performance of bundles of natural reeds. We are adapting these structures to control noise on aircraft, and spacecraft. This technology might be used in many other industrial or architectural applications where acoustic absorbers have tight constraints on weight and thickness, and may be exposed to high temperatures or liquids. Information about this technology is being made available through reports and presentations available through the NASA Technical Report Server, http:ntrs.nasa.gov. Organizations who would like to collaborate with NASA or commercialize NASAs technology

  20. The Australian Commonwealth standard of measurement for absorbed radiation dose

    International Nuclear Information System (INIS)

    Sherlock, S.L.

    1990-06-01

    This report documents the absorbed dose standard for photon beams in the range from 1 to 25 MeV. Measurements of absorbed dose in graphite irradiated by a beam of cobalt-60 gamma rays from an Atomic Energy of Canada Limited (AECL) E1 Dorado 6 teletherapy unit are reported. The measurements were performed using a graphite calorimeter, which is the primary standard for absorbed dose. The measurements are used to calibrate a working standard ion chamber in terms of absorbed dose in graphite. Details of the methods, results and correction factors applied are given in Appendices. 13 refs., 6 tabs., 6 figs

  1. Air box shock absorber for a nuclear reactor

    International Nuclear Information System (INIS)

    Pradhan, A.V.; George, J.A.

    1977-01-01

    Disclosed is an air box type shock absorber primarily for use in an ice condenser compartment of a nuclear reactor. The shock absorber includes a back plate member and sheet metal top, bottom, and front members. The front member is prefolded, and controlled clearances are provided among the members for predetermined escape of air under impact and compression. Prefolded internal sheet metal stiffeners also absorb a portion of the kinetic energy imparted to the shock absorber, and limit rebound. An external restraining rod guided by restraining straps insures that the sheet metal front member compresses inward upon impact. 6 claims, 11 figures

  2. Wideband aural acoustic absorbance predicts conductive hearing loss in children.

    Science.gov (United States)

    Keefe, Douglas H; Sanford, Chris A; Ellison, John C; Fitzpatrick, Denis F; Gorga, Michael P

    2012-12-01

    This study tested the hypothesis that wideband aural absorbance predicts conductive hearing loss (CHL) in children medically classified as having otitis media with effusion. Absorbance was measured in the ear canal over frequencies from 0.25 to 8 kHz at ambient pressure or as a swept tympanogram. CHL was defined using criterion air-bone gaps of 20, 25, and 30 dB at octaves from 0.25 to 4 kHz. A likelihood-ratio predictor of CHL was constructed across frequency for ambient absorbance, and across frequency and pressure for absorbance tympanometry. Performance was evaluated at individual frequencies and for any frequency at which a CHL was present. Absorbance and conventional 0.226-kHz tympanograms were measured in children of age three to eight years with CHL and with normal hearing. Absorbance was smaller at frequencies above 0.7 kHz in the CHL group than the control group. Based on the area under the receiver operating characteristic curve, wideband absorbance in ambient and tympanometric tests were significantly better predictors of CHL than tympanometric width, the best 0.226-kHz predictor. Accuracies of ambient and tympanometric wideband absorbance did not differ. Absorbance accurately predicted CHL in children and was more accurate than conventional 0.226-kHz tympanometry.

  3. ABSORBENCY CHARACTERISTICS OF PESHTAMALS: TRADITIONAL TURKISH WOVEN CLOTHES

    Directory of Open Access Journals (Sweden)

    KESKIN Reyhan

    2014-05-01

    Full Text Available Absorbency of textiles is defined as the ability of taking in a fluid in the manner of a sponge. Absorbency is required for comfort properties in so me clothes such as sportswear and underwear clothing, for drying properties in napkins, towels and bathrobes, for health concerns in some medical textiles such as bandages, gauze and absorbent cotton, and for cleaning properties in washclothes and mops. In this study five different fabric samples (three woven 100% cotton fabrics A, B and P respectively at plain, twill, and peshtamal weaving patterns and two 100% cotton terry towels T1 and T2 were tested. The absorbency properties of the samples were evaluated according to the droplet test, sinking time test and wicking height tests (pottasium chromate test. Peshtamal samples showed better absorbency results than plain and twill weaves and lower but close results to towel samples according to the droplet test, sinking time test and wicking height tests. The absorbency properties of peshtamals showed results close to towel samples. The void content of peshtamals is higher than plain and twill samples but closer and lower than towel samples. The good absorbency results of peshtamals might be due to the void content of peshtamals which is higher than plain and twill samples but closer and lower than towel samples. Peshtamals which are good in absorbency and light in weight might be used widespreadly in daily life for their high absorbency, and on travel for weight saving purposes.

  4. Biological dosimetry for the reconstruction of doses absorbed during accidents in radiotherapy

    International Nuclear Information System (INIS)

    Wojcik, A.; Stephan, G.; Sommer, S.; Urbanik, W.; Kukolowicz, P.; Kuszewski, T.; Gozdz, S.

    2002-01-01

    Medical radiation represents by far the largest man-made source of radiation exposure. The recent accident in a radiotherapy unit in Bialystok, Poland, clearly showed the necessity to develop biological methods allowing a reconstruction of the absorbed dose in case of an accidental exposure. We are currently analysing the frequencies of micronuclei in lymphocytes of patients undergoing radiotherapy of tumors localized in different parts of the body. The aim of the studies in the setting up to appropriate calibration curves with the help of which a dose absorbed during an accident could be estimated. In addition, the applicability of such calibration curves for quality assurance of teleradiotherapy will be considered. In order to calculate the expected frequencies of aberrations and micronuclei in lymphocytes of patients undergoing teleradiotherapy a mathematical model was developed. The modeled dose-response curves agree well with the majority of published experimental results and will serve as a basis for ongoing studies. (author)

  5. Reliability test: X-ray ring exit chambers crotch radiation absorbers. Final report

    International Nuclear Information System (INIS)

    Lynch, D.R.; Morgan, J.

    1999-01-01

    This report details the efforts by engineers at the National Synchrotron Light Source (NSLS) of Brookhaven National Laboratory (BNL) to evaluate the reliability of water-cooled radiation absorbers used in the NSLS X-ray ring. These absorbers are part of the 16 dipole vacuum chambers which comprise the arc sections of the ring. They are located at the intersections (crotch) of the beamline exit ports with the electron beam chamber, and are commonly referred to as crotches. The purpose of these efforts was to demonstrate the reliability of the crotches under operating conditions that the crotches will be subjected to over the entire expected life of the ring. The efforts described include engineering calculations, finite element analysis, conceptual design for a reliability test, test implementation and descriptions, results and conclusions related to these analyses and tests

  6. Apodised aperture assembly for high power lasers

    International Nuclear Information System (INIS)

    Bliss, E.S.; Speck, D.R.

    1975-01-01

    An apodized aperture assembly using absorbing liquid or solid to vary transmission over the cross section thereof is used to minimize deleterious diffraction effects in high power lasers. By employing, for example, an absorbing liquid of varying optical density to obtain the transmission profile, a circular aperture of this type can be used to minimize diffraction effects, thereby substantially improving the performance of a high power laser system. (U.S.)

  7. International programme on the health effects of the Chernobyl accident (IPHECA). 'Epidemiological registry' Pilot project. Reconstruction of absorbed doses from external exposure of the population living in areas of Russia contaminated as a result of the accident at the Chernobyl nuclear power plant

    International Nuclear Information System (INIS)

    Pitkevic, V.A.; Duba, V.V.; Ivanov, V.K.; Tsyb, A.F.

    1994-01-01

    In order to carry out epidemiological research on the influence of radiation factors on the health of people living in centres of population areas contaminated as a result of the Chernobyl accident, a knowledge of the amount of external and internal exposure to the thyroid gland and the whole body is crucial. After seven years of the Chernobyl accident, an attempt was made to reconstruct the complete dynamic picture of radioactive contamination of Russian territory, taking into consideration current data on the temporal behavior of the source of accidental radionuclide emissions from the reactor where the accident occurred, meteorological conditions at the time, detailed measurements of cesium 137 fall-out density on CIS territory, air exposure dose rate measurements. Such an approach will enable to determine absorbed doses in centers of population, where radiation parameters were not measured at all. 17 refs, 6 figs, 6 tabs, 1 map

  8. A variable passive low-frequency absorber

    Science.gov (United States)

    Larsen, Niels Werner; Thompson, Eric R.; Gade, Anders Christian

    2005-04-01

    Multi-purpose concert halls face a dilemma. They can host classical music concerts, rock concerts and spoken word performances in a matter of a short period. These different performance types require significantly different acoustic conditions in order to provide the best sound quality to both the performers and the audience. A recommended reverberation time for classical music may be in the range of 1.5-2 s for empty halls, where rock music sounds best with a reverberation time around 0.8-1 s. Modern rhythmic music often contains high levels of sound energy in the low frequency bands but still requires a high definition for good sound quality. Ideally, the absorption of the hall should be adjustable in all frequency bands in order to provide good sound quality for all types of performances. The mid and high frequency absorption is easily regulated, but adjusting the low-frequency absorption has typically been too expensive or requires too much space to be practical for multi-purpose halls. Measurements were made on a variable low-frequency absorber to develop a practical solution to the dilemma. The paper will present the results of the measurements as well as a possible design.

  9. Absorber Coatings for Mid-Infrared Astrophysics

    Science.gov (United States)

    Baker, Dahlia Anne; Wollack, Edward; Rostem, Karwan

    2017-01-01

    Control over optical response is an important aspect of instrument design for astrophysical imaging. Here we consider a mid-infrared absorber coating proposed for use on HIRMES (High Resolution Mid-Infrared Spectrometer), a cryogenic spectrometer which will fly on the SOFIA (Stratospheric Observatory for Infrared Astronomy) aircraft. The aim of this effort is to develop an absorptive coating for the 20-200 microns spectral range based on a graphene loaded epoxy binder (Epotek 377H) and glass microsphere scatterers (3M K1). The coatings electromagnetic response was modeled using a Matlab script and the glass microspheres were characterized by the measured size distribution, the dielectric constant, and the filling fraction. Images of the microspheres taken by a microscope were used to determine the size distribution with an ImageJ particle analysis program. Representative test samples for optical evaluation were fabricated for characterization via infrared Fourier transform spectroscopy. The optical tests will determine the material’s absorptance and reflectance. These test results will be compared to the modeled response.

  10. Method of manufacturing improved neutron absorbers

    International Nuclear Information System (INIS)

    Ito, Masahiko; Yuzuhara, Shun-ichi; Tamaki, Shohei.

    1987-01-01

    Purpose: To obtain control rods capable of suppressing swelling and having increased working life, high safety and economical advantage. Method: Boron carbide sintered body as the neutron absorber is adjusted such that the boron/carbon atomic ratio is within a range of 4.0 ± 0.2 and the average crystal grain size is of less than 5 μm. Then, for suppressing the growing of crystal grains in the course of sintering, press-sintering is applied under the conditions of a temperature at 1700 - 2200 deg C and a pressure of 100 - 500 kg/cm 2 . Aimed control rods can thus be obtained. If the average crystal grain size exceeds 5 μm, the diffusion rate of He formed by the neutron absorption reaction is fast at the grain boundary, whereas it is relatively low within the crystal grains. Accordingly, the He possessing amount is increased and the swelling is increased in the case of such large grain size that the grain boundary area per unit volume is relatively small. (Takahashi, M.)

  11. Great expectations: large wind turbines

    International Nuclear Information System (INIS)

    De Vries, E.

    2001-01-01

    This article focuses on wind turbine product development, and traces the background to wind turbines from the first generation 1.5 MW machines in 1995-6, plans for the second generation 3-5 MW class turbines to meet the expected boom in offshore wind projects, to the anticipated installation of a 4.5 MW turbine, and offshore wind projects planned for 2000-2002. The switch by the market leader Vestas to variable speed operation in 2000, the new product development and marketing strategy taken by the German Pro + Pro consultancy in their design of a 1.5 MW variable speed pitch control concept, the possible limiting of the size of turbines due to logistical difficulties, opportunities offered by air ships for large turbines, and the commissioning of offshore wind farms are discussed. Details of some 2-5 MW offshore wind turbine design specifications are tabulated

  12. [Manufactured baby food: safety expectations].

    Science.gov (United States)

    Davin, L; Van Egroo, L-D; Galesne, N

    2010-12-01

    Food safety is a concern for parents of infants, and healthcare professionals are often questioned by them about this topic. Baby food European regulation ensures high levels of safety and is more rigorous than common food regulation. Maximal limit for pesticides in baby food demonstrates the high level of requirements. This limit must be below the 10 ppb detection threshold, whatever the chemical used. Other contaminants such as nitrates are also the subject of greater expectations in baby food. Food safety risks control needs a specific know-how that baby food manufacturers have acquired and experienced, more particularly by working with producers of high quality raw material. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  13. Design and control of a point absorber wave energy converter with an open loop hydraulic transmission

    International Nuclear Information System (INIS)

    Fan, YaJun; Mu, AnLe; Ma, Tao

    2016-01-01

    Highlights: • Point absorber wave energy converter is presented. • Piston pump module captures and converts wave energy. • Hydraulic accumulator stores/releases the surplus energy. • Fuzzy controller adjusts the displacement of hydraulic motor. • Generator outputs meet the electricity demand precisely. - Abstract: In this paper, a point absorber wave energy converter combined with offshore wind turbine is proposed. In the system, the wave energy is captured and converted into hydraulic energy by a piston pump module, which is combined with a wind turbine floating platform, and then the hydraulic energy is converted into electricity energy by a variable displacement hydraulic motor and induction generator. In order to smooth and stabilize the captured wave energy, a hydraulic accumulator is applied to store and release the excess energy. In order to meet the demand power a fuzzy controller is designed to adjust the displacement of hydraulic motor and controlled the output power. Simulation under irregular wave condition has been carried out to verify the validity of the mathematical model and the effectiveness of the controller strategy. The results show that the wave energy converter system could deliver the required electricity power precisely as the motor output torque is controlled. The accumulator could damp out all the fluctuations in output power, so the wave energy would become a dispatchable power source.

  14. Motor activity improves temporal expectancy.

    Directory of Open Access Journals (Sweden)

    Lilian Fautrelle

    Full Text Available Certain brain areas involved in interval timing are also important in motor activity. This raises the possibility that motor activity might influence interval timing. To test this hypothesis, we assessed interval timing in healthy adults following different types of training. The pre- and post-training tasks consisted of a button press in response to the presentation of a rhythmic visual stimulus. Alterations in temporal expectancy were evaluated by measuring response times. Training consisted of responding to the visual presentation of regularly appearing stimuli by either: (1 pointing with a whole-body movement, (2 pointing only with the arm, (3 imagining pointing with a whole-body movement, (4 simply watching the stimulus presentation, (5 pointing with a whole-body movement in response to a target that appeared at irregular intervals (6 reading a newspaper. Participants performing a motor activity in response to the regular target showed significant improvements in judgment times compared to individuals with no associated motor activity. Individuals who only imagined pointing with a whole-body movement also showed significant improvements. No improvements were observed in the group that trained with a motor response to an irregular stimulus, hence eliminating the explanation that the improved temporal expectations of the other motor training groups was purely due to an improved motor capacity to press the response button. All groups performed a secondary task equally well, hence indicating that our results could not simply be attributed to differences in attention between the groups. Our results show that motor activity, even when it does not play a causal or corrective role, can lead to improved interval timing judgments.

  15. Gauge-invariant expectation values of the energy of a molecule in an electromagnetic field.

    Science.gov (United States)

    Mandal, Anirban; Hunt, Katharine L C

    2016-01-28

    following our partitioning, the expectation values of the molecular Hamiltonian are identical to those obtained directly in the Coulomb gauge. As a corollary of this result, the power absorbed by a molecule from a time-dependent, applied electromagnetic field is equal to the time derivative of the non-adiabatic term in the molecular energy, in any gauge.

  16. Expectations from experts in ethics

    International Nuclear Information System (INIS)

    Reinhold Brakenhielm, C.

    2008-01-01

    In this lecture, I would like to make an ethical interpretation of the regulations issued by SSI (Swedish Radiation Protection Agency) and SKI (Swedish Nuclear Power Inspectorate). I am going to define the utilitarian core of the Swedish regulatory framework, but also identify a number of non-utilitarian elements, for example a number of principles of justice presented in KASAM's State-of-the-art Report from 2004. Thereby, I also hope to clarify possible. spots of moral silence in the Swedish regulatory framework on nuclear waste. (author)

  17. Phase 2 report on the evaluation of polyacrylonitrile (PAN) as a binding polymer for absorbers used to treat liquid radioactive wastes

    International Nuclear Information System (INIS)

    Sebesta, F.; John, J.; Motl, A.

    1996-05-01

    The performance of PAN-based composite absorbers was evaluated in dynamic experiments at flow rates ranging from 25--100 bed volumes (BV) per hour. Composite absorbers with active components of ammonium molybdophosphate (AMP) PAN and K-Co ferrocyanide (KCoFC) PAN were used for separating Cs from a 1 M HNO 3 + 1 M NaNO 3 + 2 x 10 -5 M CsCl acidic simulant solution. KCoFC-PAN and two other FC-based composite absorbers were tested for separating Cs from alkaline simulant solutions containing 0.01 M to 1 M NaOH and 1 M NaNO 3 + x x 10 -4 M CsCl. The efficiency of the Cs sorption on the AMP-PAN absorber from acidic simulant solutions was negatively influenced by the dissolution of the AMP active component. At flow rates of 50 BV/hr, the decontamination factor of about 10 3 could be maintained for treatment of 380 BV of the feed. With the KCoFC-PAN absorber, the decontamination factor of about 10 3 could be maintained for a feed volume as great as 1,800 BV. In alkaline simulant solutions, significant decomposition of the active components was observed, and the best performance was exhibited by the KCoFC-PAN absorber. Introductory experiments confirmed that Cs may be washed out of the composite absorbers. Regeneration of both absorbers for repetitive use was also found to be possible. The main result of the study is that PAN was proven to be a versatile polymer capable of forming porous composite absorbers with a large number of primary absorbers. The composite absorbers proved to be capable of withstanding the harsh acidic and alkaline conditions and significant radiation doses that may be expected in the treatment of US DOE wastes. A field demonstration is proposed as a follow-on activity

  18. Consequences of nonlinear heat transport laws on expected plasma profiles

    International Nuclear Information System (INIS)

    Lackner, K.

    1987-03-01

    The expected variation of plasma pressure profiles against changes in power deposition is investigated by using a simple linear heat transport law as well as a quadratic one. Applying the quadratic transport law it can be shown that the stiffening of the resulting profiles is sufficient to understand the experimentally measured phenomenon of 'profile consistence' without further assumptions of nonlocal effects. (orig.) [de

  19. Applications of expectation maximization algorithm for coherent optical communication

    DEFF Research Database (Denmark)

    Carvalho, L.; Oliveira, J.; Zibar, Darko

    2014-01-01

    In this invited paper, we present powerful statistical signal processing methods, used by machine learning community, and link them to current problems in optical communication. In particular, we will look into iterative maximum likelihood parameter estimation based on expectation maximization al...

  20. Low fluid level in pulse rod shock absorber

    International Nuclear Information System (INIS)

    Aderhold, H.C.

    1974-01-01

    On various occasions during pulse mode operation the shim and regulating control rods would drop when the pulse rod was withdrawn. Subsequent investigation traced the problem to the pulse rod shock absorber which was found to be low in hydraulic fluid. The results of the investigation, the corrective action taken, and a method for measuring the shock absorber fluid level are presented. (author)

  1. A blast absorber test: measurement and model results

    NARCIS (Netherlands)

    Eerden, F.J.M. van der; Berg, F. van den; Hof, J. van 't; Arkel, E. van

    2006-01-01

    A blast absorber test was conducted at the Aberdeen Test Centre from 13 to 17 June 2005. The test was set up to determine the absorbing and shielding effect of a gravel pile, of 1.5 meters high and 15 by 15 meters wide, on blasts from large weapons: e.g. armor, artillery or demolition. The blast was

  2. Preparation and characterization of water-absorbing composite ...

    African Journals Online (AJOL)

    The present work introduces a novel method for the formation of water absorbing composite membrane. The prepared composite is based on chitosan, carboxymethyl cellulose (CMC), and Montmorillonite. Prepared composite membrane exhibits high water absorbing and holding capacity with increasing clay content.

  3. Shock-absorbing caster wheel is simple and compact

    Science.gov (United States)

    Kindley, R. J.

    1968-01-01

    Compact shock-absorbing caster wheel mitigates or absorbs shock by a compressible tire which deforms into a cavity between its inner edge and the wheel hub. A tee-shaped annular ring embedded in the tire distributes loads more uniformly throughout both wheel and tire.

  4. Radiation sensitive medium for recording an absorbed dose distribution

    DEFF Research Database (Denmark)

    2017-01-01

    The invention relates to a radiation sensitive medium for recording an absorbed dose distribution from an external radiation source such as e.g. a linear particle accelerator used for e.g. cancer treatment or radiation processing. The invention further relates to a method for measuring the absorbed...... doses distribution in a radiation sensitive medium....

  5. Nylon shock absorber prevents injury to parachute jumpers

    Science.gov (United States)

    Mandel, J. A.

    1966-01-01

    Nylon shock absorbers reduce the canopy-opening shock of a parachute to a level that protects the wearer from injury. A shock absorber is mounted on each of the four risers between the shroud lines and the harness. Because of their size and location, they pose no problem in repacking the chute and harness after a jump.

  6. Preparation and characterization of water-absorbing composite ...

    African Journals Online (AJOL)

    ABCO

    2012-08-16

    Aug 16, 2012 ... The present work introduces a novel method for the formation of water absorbing composite membrane. The prepared composite is based on chitosan, carboxymethyl cellulose (CMC), and. Montmorillonite. Prepared composite membrane exhibits high water absorbing and holding capacity with increasing ...

  7. Effect of Bilirubin concentration on radiation absorbed dose ...

    African Journals Online (AJOL)

    Results indicate that at low concentrations (25 mol/L to 76 mol/L) absorbed doses decreased with increase in bilirubin concentration. At higher bilirubin concentrations (76 mol/L to 460 mol/L) and beyond, there was an increase in absorption with a strong positive correlation (r = 0.92) between dose absorbed and ...

  8. The role of Joseph Lister in developing the absorbable ligature.

    Science.gov (United States)

    Hall, M J

    2001-08-01

    Joseph Lister is associated with pioneering work on antisepsis. However an important but less well-known contribution to surgical progress was his work on the absorbable suture. This article details the problems Lister faced in operative surgery, his observations and experiments that lead to his development of an absorbable suture.

  9. Simulated mixed absorbers and effective atomic numbers for γ ...

    Indian Academy of Sciences (India)

    The total -ray interaction crosss-sections on mixed absorbers were determined at 662 keV with a view to study the effective atomic numbers for -ray absorption under narrow beam good geometry set-up. The measurements were taken for the combination of metallic absorbers like aluminium, copper, lead and mercury ...

  10. Distribution of Doppler Redshifts of Associated Absorbers of SDSS ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Doppler redshifts of a sample of Mg II associated absorbers of SDSS DR7 quasars are analysed. We find that there might be three Gaussian components in the distribution of the Doppler redshift. The first Gaussian component, with the peak being located at Dopp = -0.0074, probably arises from absorbers ...

  11. Experimental investigation of control absorber blade effects in a modern 10x10 BWR assembly

    International Nuclear Information System (INIS)

    Jatuff, F.; Grimm, P.; Murphy, M.; Luethi, A.; Seiler, R.; Joneja, O.; Meister, A.; Geemert, R. van; Brogli, R.; Chawla, R.; Williams, T.; Helmersson, S.

    2001-01-01

    The accurate estimation of reactor physics parameters related to the presence of cruciform absorber blades. In Boiling Water Reactors (BWR) is important for safety assessment, and for achieving a flexible operation during the cycle. Characteristics which are affected strongly include the power distribution for controlled core regions and its impact on linear heat generation rate margins, as well as the build-up of plutonium, and its influence on core excess reactivity and the reactivity worth of the shutdown system. PSI and the Swiss Nuclear Utilities (UAK) are conducting an experimental reactor physics programme related to modern Light Water Reactor (LWR) fuel assemblies, as employed in the Swiss nuclear power plants: the so-called. LWR-PROTEUS Phase I project. A significant part of this project has been devoted to the characterization of highly heterogeneous BWR fuel elements in the presence of absorber blades. The paper presents typical results for the performance of modern lattice codes in the estimation of controlled assembly reaction rate distributions, the sensitivity to the geometrical and material characterization, and a preliminary comparison of reflected-test-zone calculations with experimental reaction rate distributions measured in a Westinghouse SVEA-96+ assembly under full-density water moderation conditions in the presence of Westinghouse boron-carbide absorber blades. (author)

  12. Performance evaluation of CFRP-rubber shock absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Lamanna, Giuseppe, E-mail: giuseppe.lamanna@unina2.it; Sepe, Raffaele, E-mail: giuseppe.lamanna@unina2.it [Department of Industrial and Information Engineering, Second University of Naples, via Roma, 29 - 81031 Aversa (Italy)

    2014-05-15

    In the present work a numerical investigation on the energy absorbing capability of dedicated structural components made of a carbon fiber reinforced polymer and an emulsion polymerised styrene butadiene rubber is reported. The shock absorbers are devices designed to absorb large amounts of energy by sacrificing their own structural integrity. Their aim is to cushion the effects of an impact phenomenon with the intent to preserve other structures from global failure or local damaging. Another important role of shock absorbers is reducing the peak of the acceleration showed during an impact phenomenon. This effect is of considerable interest in the case of vehicles to preserve passengers’ safety. Static and dynamic numerical results are compared with experimental ones in terms of mean crushing forces, energy and peak crushing. The global performance of the absorbers has been evaluated by referencing to a proposed quality index.

  13. CMS: Beyond all possible expectations

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    After having retraced the entire Standard Model up to the Top, the CMS collaboration is ready to go further and continue the success of what Guido Tonelli – its spokesperson – defines as a ‘magic year’. Things evolve fast at CMS, but scientists have taken up the challenge and are ready for the future.   ‘Enthusiasm’ is the word that best describes the feeling one gets when talking to Guido Tonelli. “In just a few months we have rediscovered the Standard Model and have gone even further by producing new results for cross-sections, placing new limits on the creation of heavy masses, making studies on the excited states of quarks, and seeking new resonances. We could not have expected so much such a short space of time. It’s fantastic”, he says. “We went through the learning phase very smoothly. Our detector was very quickly ready to do real physics and we were able to start to produce results almost ...

  14. Educational Expectations and Media Cultures

    Directory of Open Access Journals (Sweden)

    Petra Missomelius

    2014-11-01

    Full Text Available This article investigates themedia-supported educational resources that arecurrently under discussion, such as OERs and MOOCs. Considering the discursive connection between these formats, which is couched in terms of educational freedom and openness, the article’sthesis is that these are expectations which are placed on the media technologies themselves, andthen transferred to learning scenarios. To this end, the article will pursue such questions as: What are the learners, learning materials and learning scenarios allegedly free from or free for? What obstructive configurations should be omitted? To what extent are these characteristics which are of a nature to guaranteelearning processes in the context of lifelong learning or can these characteristics better be attributed to the media technologies themselves and the ways in which they are used? What advantages or new accentuations are promised by proponents of theeducation supplied by media technology? Which discourses provide sustenance for such implied “post-typographic educational ideals” (Giesecke 2001 and Lemke 1998? The importance to learners, teachers and decision-makers at educational institutions of being well informed as far as media is concerned is becoming increasingly apparent.

  15. Smoking Outcome Expectancies among College Students.

    Science.gov (United States)

    Brandon, Thomas H.; Baker, Timothy B.

    Alcohol expectancies have been found to predict later onset of drinking among adolescents. This study examined whether the relationship between level of alcohol use and expectancies is paralleled with cigarette smoking, and attempted to identify the content of smoking expectancies. An instrument to measure the subjective expected utility of…

  16. Experimental demonstration of trapping waves with terahertz metamaterial absorbers on flexible polyimide films

    Science.gov (United States)

    Wang, Wei; Liu, Jinsong; Wang, Kejia

    2016-02-01

    We present the design, numerical simulations and experimental measurements of an asymmetric cross terahertz metamaterial absorber (MPA) on ultra-flexible polyimide film. The perfect metamaterial absorber composed of two structured metallic layers separated with a polyimide film with a total thickness of functional layers much smaller than the operational wavelength. Two distinct absorption peaks are found at resonance frequencies of 0.439THz and 0.759 THz with resonance amplitude of near unity, which are in good agreement with the simulation results. The sample is also measured by a THz-TDS imaging system to illustrate the absorption characterization. The scanning images show that the sample could act as a perfect absorber at specific resonance frequencies while a perfect reflector at off resonance frequencies. To illustrate the physical mechanism behind these spectral responses, the distribution of the power loss and surface current are also presented. The result shows that the incident wave is trapped and absorbed by the polyimide dielectric layer at different vicinities of the proposed asymmetric cross MPA for the two absorption peaks. Furthermore, the index sensing performance of the structure is also investigated, and the calculated sensitivity is 90GHz/RIU for f1 mode and 154.7GHz/RIU for f2 mode, indicating that the higher frequency resonance absorption peak has better potential applications in sensing and detection. The ultra-flexible, low cost, high intensity dual band terahertz absorbers may pave the way for designing various terahertz functional devices, such as ultrasensitive terahertz sensors, spatial light modulators and filters.

  17. Transduction on Directed Graphs via Absorbing Random Walks.

    Science.gov (United States)

    De, Jaydeep; Zhang, Xiaowei; Lin, Feng; Cheng, Li

    2017-08-11

    In this paper we consider the problem of graph-based transductive classification, and we are particularly interested in the directed graph scenario which is a natural form for many real world applications.Different from existing research efforts that either only deal with undirected graphs or circumvent directionality by means of symmetrization, we propose a novel random walk approach on directed graphs using absorbing Markov chains, which can be regarded as maximizing the accumulated expected number of visits from the unlabeled transient states. Our algorithm is simple, easy to implement, and works with large-scale graphs on binary, multiclass, and multi-label prediction problems. Moreover, it is capable of preserving the graph structure even when the input graph is sparse and changes over time, as well as retaining weak signals presented in the directed edges. We present its intimate connections to a number of existing methods, including graph kernels, graph Laplacian based methods, and interestingly, spanning forest of graphs. Its computational complexity and the generalization error are also studied. Empirically our algorithm is systematically evaluated on a wide range of applications, where it has shown to perform competitively comparing to a suite of state-of-the-art methods. In particular, our algorithm is shown to work exceptionally well with large sparse directed graphs with e.g. millions of nodes and tens of millions of edges, where it significantly outperforms other state-of-the-art methods. In the dynamic graph setting involving insertion or deletion of nodes and edge-weight changes over time, it also allows efficient online updates that produce the same results as of the batch update counterparts.

  18. Preparation of Active Absorbent for Flue Gas Desulfurization From Coal Bottom Ash: Effect of Absorbent Preparation Variables

    Directory of Open Access Journals (Sweden)

    Chang Chin Li, Lee Keat Teong, Subhash Bhatia and Abdul Rahman Mohamed

    2012-08-01

    Full Text Available An active absorbent for flue gas desulfurization was prepared from coal bottom ash, calcium oxide (CaO and calcium sulfate by hydro-thermal process. The absorbent was examined for its micro-structural properties. The experiments conducted were based on Design Of Experiments (DOE according to 23 factorial design. The effect of various absorbent preparation variables such as ratio of CaO to bottom ash (A, hydration temperature (B and hydration period (C towards the BET (Brunauer-Emmett-Teller specific surface area of the absorbent were studied. At a CaO to bottom ash ratio = 2, hydration temperature = 200 ?C and hydration period = 10 hrs, absorbent with a surface area of 90.1 m2/g was obtained. Based on the analysis of the factorial design, it was concluded that factor A and C as well as the interaction of factors ABC and BC are the significant factors that effect the BET surface area of the absorbent. A linear mathematical model that describes the relation between the independent variables and interaction between variables towards the BET specific surface area of the absorbent was also developed. Analysis of variance (ANOVA showed that the model was significant at 1% level.Key Words: Absorbent, Bottom Ash, Design Of Experiments, Desulfurization, Surface Area.

  19. Mid-infrared mode-locked pulse generation with multilayer black phosphorus as saturable absorber.

    Science.gov (United States)

    Qin, Zhipeng; Xie, Guoqiang; Zhao, Chujun; Wen, Shuangchun; Yuan, Peng; Qian, Liejia

    2016-01-01

    A mid-infrared saturable absorber mirror is successfully fabricated by transferring the mechanically exfoliated black phosphorus onto the gold-coated mirror. With the as-prepared black phosphorus saturable absorber mirror, a continuous-wave passively mode-locked Er:ZBLAN fiber laser is demonstrated at the wavelength of 2.8 μm, which delivers a maximum average output power of 613 mW, a repetition rate of 24 MHz, and a pulse duration of 42 ps. To the best of our knowledge, this is the first time a black phosphorus mode-locked laser at 2.8 μm wavelength has been demonstrated. Our results demonstrate the feasibility of black phosphorus flake as a new two-dimensional material for application in mid-infrared ultrafast photonics.

  20. Symmetric Absorber-Coupled Far-Infrared Microwave Kinetic Inductance Detector

    Science.gov (United States)

    U-yen, Kongpop (Inventor); Wollack, Edward J. (Inventor); Brown, Ari D. (Inventor); Stevenson, Thomas R. (Inventor); Patel, Amil A. (Inventor)

    2016-01-01

    The present invention relates to a symmetric absorber-coupled far-infrared microwave kinetic inductance detector including: a membrane having an absorber disposed thereon in a symmetric cross bar pattern; and a microstrip including a plurality of conductor microstrip lines disposed along all edges of the membrane, and separated from a ground plane by the membrane. The conducting microstrip lines are made from niobium, and the pattern is made from a superconducting material with a transition temperature below niobium, including one of aluminum, titanium nitride, or molybdenum nitride. The pattern is disposed on both a top and a bottom of the membrane, and creates a parallel-plate coupled transmission line on the membrane that acts as a half-wavelength resonator at readout frequencies. The parallel-plate coupled transmission line and the conductor microstrip lines form a stepped impedance resonator. The pattern provides identical power absorption for both horizontal and vertical polarization signals.

  1. Dynamic Influences of Wind Power on The Power System

    DEFF Research Database (Denmark)

    Rosas, Pedro Andrè Carvalho

    2004-01-01

    . The flicker and frequency deviations are the main power quality parameters presented. The power system stability concentrates on the voltage stability and on the power system oscillations. From the cases studies, voltage and thefrequency variations were smaller than expected from the large-scale wind power...

  2. Flower garden trees' ability to absorb solar radiation heat for local heat reduction

    Science.gov (United States)

    Maulana, Muhammad Ilham; Syuhada, Ahmad; Hamdani

    2017-06-01

    Banda Aceh as an urban area tends to have a high air temperature than its rural surroundings. A simple way to cool Banda Aceh city is by planting urban vegetation such as home gardens or parks. In addition to aesthetics, urban vegetation plays an important role as a reducer of air pollution, oxygen producer, and reducer of the heat of the environment. To create an ideal combination of plants, knowledge about the ability of plants to absorb solar radiation heat is necessary. In this study, some types of flowers commonly grown by communities around the house, such as Michelia Champaka, Saraca Asoka, Oliander, Adenium, Codiaeum Variegatum, Jas Minum Sambac, Pisonia Alba, Variegata, Apium Graveolens, Elephantopus Scaber, Randia, Cordylin.Sp, Hibiscus Rosasinensis, Agave, Lili, Amarilis, and Sesamum Indicum, were examined. The expected benefit of this research is to provide information for people, especially in Banda Aceh, on the ability of each plant relationship in absorbing heat for thermal comfort in residential environments. The flower plant which absorbs most of the sun's heat energy is Hibiscus Rosasinensis (kembang sepatu) 6.2 Joule, Elephantopus Scaber.L (tapak leman) 4.l Joule. On the other hand, the lowest heat absorption is Oliander (sakura) 0.9 Joule.

  3. Siegmund duality with applications to the neutral Moran model conditioned on never being absorbed

    International Nuclear Information System (INIS)

    Huillet, Thierry

    2010-01-01

    We first consider the classical neutral Moran model with two alleles whose fate is either to become extinct or to reach fixation. We study an ergodic version of the Moran model obtained by conditioning it to never hit the boundaries, making use of a Doob transform. We call it the recurrent Moran model. We show that the Siegmund dual of the recurrent Moran process exists and is a substochastic birth and death chain. Conditioning this process to exit in its natural absorbing state, we construct a process with a unique absorbing state which is intertwined to the original recurrent Moran process. The time needed for the intertwined process to first hit its absorbing state is related to the time needed to reach stationarity for the recurrent Moran process. Using spectral information on the intertwined chain, we extract limiting information on this first hitting time that shows that there is no abrupt relaxation to equilibrium for the recurrent Moran chain. This makes use of the relation between duality and intertwining and strong stationary times. Other related transition times of the recurrent Moran chain are also briefly investigated, namely the first return time to the ground state and the expected time needed to move from one end to the other end of the state space.

  4. An overview of the development, testing, and application of composite absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Sebesta, F. [Czech Technical Univ., Brehova (Czech Republic); John, J. [Los Alamos National Lab., NM (United States)

    1995-02-01

    Although inorganic exchangers offer many advantages for removing selected elements from radioactive waste streams, few of these materials are suitable for use in packed-bed columns. We review various adaptations of inorganic exchangers for use in columns, which include granular forms of the intrinsic absorbers, absorber compounds supported on other materials, and composite absorbers that use organic or inorganic binders. An organic binding polymer of polyacrylonitrile (PAN), developed at the Czech Technical University, has been demonstrated to offer advantages. We describe general methods for preparing inorganic exchange materials, which then are incorporated into PAN-based composites. Such PAN composites have been used to remove selected radionuclides from a variety of liquid waste streams. Sixteen different PAN composites were prepared for testing at Los Alamos National Laboratory (LANL) as part of an evaluation of potential partitioning agents for remediating the liquid waste in underground storage tanks at the Hanford site near Richland, Washington. Our collaboration with LANL is expected to continue for another 2 years.

  5. BAT AGN Spectroscopic Survey. VIII. Type 1 AGN with Massive Absorbing Columns

    Science.gov (United States)

    Shimizu, T. Taro; Davies, Richard I.; Koss, Michael; Ricci, Claudio; Lamperti, Isabella; Oh, Kyuseok; Schawinski, Kevin; Trakhtenbrot, Benny; Burtscher, Leonard; Genzel, Reinhard; Lin, Ming-yi; Lutz, Dieter; Rosario, David; Sturm, Eckhard; Tacconi, Linda

    2018-04-01

    We explore the relationship between X-ray absorption and optical obscuration within the BAT AGN Spectroscopic Survey (BASS), which has been collecting and analyzing the optical and X-ray spectra for 641 hard X-ray selected (E > 14 keV) active galactic nuclei (AGNs). We use the deviation from a linear broad Hα-to-X-ray relationship as an estimate of the maximum optical obscuration toward the broad line region (BLR) and compare the A V to the hydrogen column densities ({N}{{H}}) found through systematic modeling of their X-ray spectra. We find that the inferred columns implied by A V toward the BLR are often orders of magnitude less than the columns measured toward the X-ray emitting region, indicating a small-scale origin for the X-ray absorbing gas. After removing 30% of Sy 1.9s that potentially have been misclassified due to outflows, we find that 86% (164/190) of the Type 1 population (Sy 1–1.9) are X-ray unabsorbed as expected based on a single obscuring structure. However, 14% (26/190), of which 70% (18/26) are classified as Sy 1.9, are X-ray absorbed, suggesting that the BLR itself is providing extra obscuration toward the X-ray corona. The fraction of X-ray absorbed Type 1 AGNs remains relatively constant with AGN luminosity and Eddington ratio, indicating a stable BLR covering fraction.

  6. Thermo-active building systems and sound absorbers: Thermal comfort under real operation conditions

    DEFF Research Database (Denmark)

    Köhler, Benjamin; Rage, Nils; Chigot, Pierre

    2018-01-01

    Radiant systems are established today and have a high ecological potential in buildings while ensuring thermal comfort. Free-hanging sound absorbers are commonly used for room acoustic control, but can reduce the heat exchange when suspended under an active slab. The aim of this study is to evalu......Radiant systems are established today and have a high ecological potential in buildings while ensuring thermal comfort. Free-hanging sound absorbers are commonly used for room acoustic control, but can reduce the heat exchange when suspended under an active slab. The aim of this study...... is to evaluate the impact on thermal comfort of horizontal and vertical free-hanging porous sound absorbers placed in rooms of a building cooled by Thermo-Active Building System (TABS), under real operation conditions. A design comparing five different ceiling coverage ratios and two room types has been...... implemented during three measurement periods. A clear correlation between increase of ceiling coverage ratio and reduction of thermal comfort could not be derived systematically for each measurement period and room type, contrarily to what was expected from literature. In the first two monitoring periods...

  7. An overview of the development, testing, and application of composite absorbers

    International Nuclear Information System (INIS)

    Sebesta, F.; John, J.

    1995-02-01

    Although inorganic exchangers offer many advantages for removing selected elements from radioactive waste streams, few of these materials are suitable for use in packed-bed columns. We review various adaptations of inorganic exchangers for use in columns, which include granular forms of the intrinsic absorbers, absorber compounds supported on other materials, and composite absorbers that use organic or inorganic binders. An organic binding polymer of polyacrylonitrile (PAN), developed at the Czech Technical University, has been demonstrated to offer advantages. We describe general methods for preparing inorganic exchange materials, which then are incorporated into PAN-based composites. Such PAN composites have been used to remove selected radionuclides from a variety of liquid waste streams. Sixteen different PAN composites were prepared for testing at Los Alamos National Laboratory (LANL) as part of an evaluation of potential partitioning agents for remediating the liquid waste in underground storage tanks at the Hanford site near Richland, Washington. Our collaboration with LANL is expected to continue for another 2 years

  8. Siegmund duality with applications to the neutral Moran model conditioned on never being absorbed

    Science.gov (United States)

    Huillet, Thierry

    2010-09-01

    We first consider the classical neutral Moran model with two alleles whose fate is either to become extinct or to reach fixation. We study an ergodic version of the Moran model obtained by conditioning it to never hit the boundaries, making use of a Doob transform. We call it the recurrent Moran model. We show that the Siegmund dual of the recurrent Moran process exists and is a substochastic birth and death chain. Conditioning this process to exit in its natural absorbing state, we construct a process with a unique absorbing state which is intertwined to the original recurrent Moran process. The time needed for the intertwined process to first hit its absorbing state is related to the time needed to reach stationarity for the recurrent Moran process. Using spectral information on the intertwined chain, we extract limiting information on this first hitting time that shows that there is no abrupt relaxation to equilibrium for the recurrent Moran chain. This makes use of the relation between duality and intertwining and strong stationary times. Other related transition times of the recurrent Moran chain are also briefly investigated, namely the first return time to the ground state and the expected time needed to move from one end to the other end of the state space.

  9. Revisiting the incidence of Mg II absorbers along the blazar sightlines

    Science.gov (United States)

    Mishra, Sapna; Chand, Hum; Gopal-Krishna; Joshi, Ravi

    2018-04-01

    It is believed that the cool gas clouds traced by Mg II absorption, within a velocity offset of 5000 km/s from the background quasar, are associated with the quasar itself, whereas the absorbers seen at larger velocity offsets towards us are intervening systems and hence their existence is completely independent of the background quasar. Recent evidence by Bergeron et al. 2011 (hereafter BBM), however, seriously questions this canonical view, by showing that the number density of intervening Mg II absorbers along the sightlines towards 45 blazars is, on average, 2 times the expectation based on the Mg II absorption systems seen on the sightlines to normal QSOs. Given the serious implications of this finding, it becomes important to revisit this issue by enlarging the source sample and subjecting it to an independent analysis. Here, we first report our results based on a re-analysis of the spectroscopic data for the BBM sample; this has reproduced their factor 2 excess in dN/dz along blazar sightlines, vis-a-vis the normal QSOs. Next, we assemble a 6 times larger sample of blazar sightlines, albeit with lower SNR. Using this enlarged sample together with the BBM sample, our analysis shows that the dN/dz of Mg II absorbers statistically matches that known for normal QSO sightlines.

  10. Effect of Sand Base Grade and Density of Moulding Sands with Sodium Silicate on Effectiveness of Absorbing Microwaves

    Directory of Open Access Journals (Sweden)

    Stachowicz M.

    2016-09-01

    Full Text Available In the paper, presented is a research on effectiveness of absorbing electromagnetic waves at frequency 2.45 GHz by unhardened moulding sands prepared of three kinds of high-silica base and a selected grade of sodium silicate. Measurements of power loss of microwave radiation (Pin expressed by a total of absorbed power (Pabs, output power (Pout and reflected power (Pref were carried-out on a stand of semiautomatic microwave slot line. Values of microwave power loss in the rectangular waveguide filled with unhardened moulding sands served for determining effectiveness of microwave heating. Balance of microwave power loss is of technological and economical importance for manufacture of high-quality casting moulds and cores of various shapes and sizes. It was found that relative density influences parameters of power output and power reflected from samples of moulding sand placed in a waveguide. Absorption expressed by the parameter Pabs is not related to granularity of high-silica base: fine, medium and coarse. It was found that the semiautomatic microwave slot line supports evaluation of effectiveness of microwave absorption on the grounds of power loss measurements and enables statistic description of influence of relative density of the sandmix on penetration of electromagnetic waves in unhardened moulding sands.

  11. ANALYSIS OF STUDENTS' MATHEMATICAL POWER IN TERMS OF STIFIN TEST

    Directory of Open Access Journals (Sweden)

    Isna Rafianti

    2017-01-01

    Full Text Available This research is motivated by the poor performance of students in particular mathematical power. One reason is that learning tends to be centered on teachers who emphasize the procedural process, mechanistic task and less provide opportunities for students to develop the ability to think mathematically. In terms of learning, each individual has their advantages and disadvantages to absorb the lessons given. But in the world of education is now known various methods in order to meet the demands of individual differences, one of which is STIFIn to determine the dominance of machine intelligence to make students more comfortable in the learning process that is expected to enhance the mathematical power. This research approach is qualitative descriptive that seeks to analyze the characteristics of students’ mathematical power in terms of STIFIn. This research was conducted in SMAN 2 Kota Serang, with research subjects are five students of eleven grade derived from each type STIFIn different categories according to STIFIn. Instruments in this study are mathematical power test and interview. The results showed that mathematical power of Thinking and Sensing type has higher than the other type, followed by the type Feeling, Intuiting and the last is the type of Instinct.

  12. RF electromagnetic wave absorbing properties of ferrite polymer composite materials

    International Nuclear Information System (INIS)

    Dosoudil, Rastislav; Usakova, Marianna; Franek, Jaroslav; Slama, Jozef; Olah, Vladimir

    2006-01-01

    The frequency dispersion of complex initial (relative) permeability (μ * =μ ' -jμ ' ') and the electromagnetic wave absorbing properties of composite materials based on NiZn sintered ferrite and a polyvinylchloride (PVC) polymer matrix have been studied in frequency range from 1MHz to 1GHz. The complex permeability of the composites was found to increase as the ferrite content increased, and was characterized by frequency dispersion localized above 50MHz. The variation of return loss (RL) of single-layer RF absorbers using the prepared composite materials has been investigated as a function of frequency, ferrite content and the thickness of the absorbers

  13. Enel expects privatization to be completed

    International Nuclear Information System (INIS)

    Anon

    2006-01-01

    The collapse of the coalition will probably mean that the sale of state-owned stakes in two distribution companies and all the heating plants will not be completed and nor will privatisation at Zapadoslovenska energetika. Most important for the energy sector is uncertainty regarding the major privatization project of this government - finding a new owner of 66% of Slovenske elektrarne shares. The state expects to receive about 32 billion Slovak crowns (842.105 million EUR) from Enel for this stake. 'The cabinet has approved the privatization under certain conditions and those have to be met now,' answered the leader of the KDH deputy's club, Pavol Minarik, to the question whether the cabinet would still be able to muster sufficient votes in parliament to pass the Act on the national nuclear account. All other so-called delaying conditions are in the competence of the cabinet or the Ministry of Economy of the Slovak Republic and the opposition, which opposes privatization, cannot influence them. The act will address the financing of debts related to the liquidation of the V1 and A1 nuclear power plants. (authors)

  14. Crack characterisation using invariable feature extraction in stainless steel specimen used for absorber tubes of CSP applications via EMAT

    DEFF Research Database (Denmark)

    Cheng, Liang; Kogia, Maria; Mohimi, Abbas

    2017-01-01

    Absorber tubes are one of the most critical components of parabolic trough Concentrated Solar Plants (CSPs). Due to the high temperatures where these tubes perform at with concentration of sunlight, it is very likely for them to get damaged such as crack and mass loss etc., and lose functionality...... of power generation. Therefore, the monitoring of their structural health via Non-Destructive Testing (NDT) techniques is regarded as essential for preventing them from being significantly defective and thereby reducing maintenance cost. Non-contact method is one of the best inspection candidates, which...... is more reliable to the tubes at high temperature through a review and the access to the absorber tubes is limited. In this paper, the crack detection and quantification for stainless steel specimen used for absorber tube using Electromagnetic Acoustic Transducers (EMATs) is presented. Through numerical...

  15. COMPARISON OF ABSORBABLE EXTRA LONG TERM POLY HYDROXY BUTYRATE SUTURE VS NON ABSORBABLE (POLYPROPYLENE SUTURE FOR ABDOMINAL WALL CLOSURE

    Directory of Open Access Journals (Sweden)

    Mallikarjun

    2015-07-01

    Full Text Available PURPOSE: The aim of study is to compare Continuous technique with non - absorbable sutures, Interrupted technique with non - absorbable sutures and Continuous technique with slowly absorbable sutures Focusing mainly on incidence of incisional hernias, burst abdomen, wound infections, chronic wound pain, suture sinus, stitch granuloma, time for rectus closure. METHODOLOGY : Study was conducted for a period of one year on 271 randomized patients with primary elective midline laparotomy in our hospital . patients are divided into group I includes 102 patients with continuous technique using non absorbable polypropylene, group II includes 91 patients with interrupted technique using non absorbable polypropylene and group III includes 78 patients with continuous slowly absorbable polyhydroxybutyrate. RESULTS: No significant difference observed in incidence of wound infections and burst abdomen in all the 3 groups but relatively higher incidence of wound infections in noted our hospital. Incidence of stich granuloma suture sinus and chronic wound pain is more with interrupted technique than continuous technique and are more with non - absor bable suture material. CONCLUSION: Incidence of incisional hernias, suture complications like suture sinus, stitch granuloma can be more effectively reduced with slowly absorbable continuous sutures.

  16. Direct growth of graphene on quartz substrate as saturable absorber for femtosecond solid-state laser

    International Nuclear Information System (INIS)

    Xu, S C; Man, B Y; Jiang, S Z; Chen, C S; Liu, M; Yang, C; Gao, S B; Zhang, C; Feng, D J; Huang, Q J; Hu, G D; Chen, X F

    2014-01-01

    We present a novel method for the direct metal-free growth of graphene on quartz substrate. The direct-grown graphene yields excellent nonlinear saturable absorption properties and is demonstrated to be suitable as a saturable absorber (SA) for an ultrafast solid-state laser. Nearly Fourier-limited 367 fs was obtained at a central wavelength of 1048 nm with a repetition rate of 105.7 MHz. At a pump power of 7.95 W, the average output power was 1.93 W and the highest pulse energy reached 18.3 nJ, with a peak power of 49.8 kW. Our work opens an easy route for making a reliable graphene SA with a mode-locking technique and also displays an exciting prospect in making low-cost and ultrafast lasers. (letter)

  17. Non-Newtonian Flow-Induced Deformation From Pressurized Cavities in Absorbing Porous Tissues

    Science.gov (United States)

    Ahmed, Aftab; Siddique, Javed

    2017-11-01

    We investigate the behavior of a spherical cavity in a soft biological tissue modeled as a deformable porous material during an injection of non-Newtonian fluid that follows a power law model. Fluid flows into the neighboring tissue due to high cavity pressure where it is absorbed by capillaries and lymphatics at a rate proportional to the local pressure. Power law fluid pressure and displacement of solid in the tissue are computed as function of radial distance and time. Numerical solutions indicate that shear thickening fluids exhibit less fluid pressure and induce small solid deformation as compared to shear thinning fluids. The absorption in the biological tissue increases as a consequence of flow induced deformation for power law fluids. In most cases non-Newtonian results are compared with viscous fluid case to magnify the differences.

  18. Of Hope, Fear and Rational Expectations

    DEFF Research Database (Denmark)

    Søgaard, Villy

    2011-01-01

    The study explores how gender and differences in preferences affect subjective expectations among a group of students.......The study explores how gender and differences in preferences affect subjective expectations among a group of students....

  19. What to Expect During a Colonoscopy

    Medline Plus

    Full Text Available ... Blog Follow ACG on Twitter Patients ACG Home / Media / What to Expect During a Colonoscopy What to Expect During a Colonoscopy Prep. Sedation. Procedure. Post-Procedure. This new educational video for GI patients, produced by the ...

  20. What to Expect During a Colonoscopy

    Medline Plus

    Full Text Available ... Home / Media / What to Expect During a Colonoscopy What to Expect During a Colonoscopy Prep. Sedation. Procedure. ... Center GI Health and Disease Recursos en Español What is a Gastroenterologist? Video and Audio Podcasts Digestive ...

  1. C-Section Recovery: What to Expect

    Science.gov (United States)

    ... also recovering from pregnancy. Here's what to expect: Vaginal discharge (lochia). Expect a bright red, heavy flow of ... your health care provider if you have heavy vaginal bleeding, discharge with a foul odor, or you have a ...

  2. What to Expect During a Colonoscopy

    Medline Plus

    Full Text Available ... reflect the current state-of-the-art scientific work and are based on the principles of evidence- ... Home / Media / What to Expect During a Colonoscopy What to Expect During a Colonoscopy Prep. Sedation. Procedure. ...

  3. Catalog of strong MgII absorbers (Lawther+, 2012)

    DEFF Research Database (Denmark)

    Lawther, D.; Paarup, Troels; Schmidt, Morten L.

    2012-01-01

    Here we present a catalog of strong (rest equivalent width Wr> intervening Mg II absorbers in the SDSS Data Release 7 quasar catalog (2010AJ....139.2360S, Cat. VII/260). The intervening absorbers were found by a semi-automatic algorithm written in IDL - for details of the algorithm see section 2...... of our paper. A subset of the absorbers have been visually inspected - see the MAN_OK flag in the catalog. The number of sightlines searched, tabulated by absorber redshift, i.e. g(z), is available as an ASCII table (for S/N>8 and S/N>15). All analysis in our paper is based on the SNR>8 coverage......, and considers only sight-lines towards non-BAL quasars. Any questions regarding the catalog should be sent to Daniel Lawther (unclellama(at)gmail.com). (3 data files)....

  4. Development of Novel Two-Photon Absorbing Chromophores

    National Research Council Canada - National Science Library

    Cooper, Thomas M; Heinrichs, James; Tan, Loon-Seng; Urbas, Augustine M; Fleitz, Paul A; Rogers, Joy E; Slagle, Jonathan E; McLean, Daniel G; Sutherland, Richard L; Brant, Mark

    2006-01-01

    There has been much interest in the development of two-photon absorbing materials and many efforts to understand the nonlinear absorption properties of these dyes, but this area is still not well understood...

  5. Two-dimensional QR-coded metamaterial absorber

    Science.gov (United States)

    Sui, Sai; Ma, Hua; Wang, Jiafu; Pang, Yongqiang; Zhang, Jieqiu; Qu, Shaobo

    2016-01-01

    In this paper, the design of metamaterial absorbers is proposed based on QR coding and topology optimization. Such absorbers look like QR codes and can be recognized by decoding softwares as well as mobile phones. To verify the design, two lightweight wideband absorbers are designed, which can achieve wideband absorption above 90 % in 6.68-19.30 and 7.00-19.70 GHz, respectively. More importantly, polarization-independent absorption over 90 % can be maintained under incident angle within 55°. The QR code absorber not only can achieve wideband absorption, but also can carry information such as texts and Web sites. They are of important values in applications such identification and electromagnetic protection.

  6. Fabrication and characterization of absorber pellets for FFTF irradiation testing

    International Nuclear Information System (INIS)

    Wilson, C.N.; Hollenberg, G.W.

    1981-01-01

    Methods used for characterization of B 4 C powder and fabricated pellets are summarized. Fabrication techniques used at HEDL for absorber test pellets are reviewed and selected powder and pellet characterization data are presented

  7. Determination of Absorbed Dose Using a Dosimetric Film

    International Nuclear Information System (INIS)

    Scarlat, F.; Scarisoreanu, A.; Oane, M.; Badita, E.; Mitru, E.

    2009-01-01

    This paper presents the absorbed dose measurements by means of the irradiated dosimetric reference films. The dose distributions were made by MULTIDATA film densitometer using RTD-4 software, in INFLPR Linear Accelerator Department

  8. Analysis of buffering process of control rod hydraulic absorber

    International Nuclear Information System (INIS)

    Bao Jishi; Qin Benke; Bo Hanliang

    2011-01-01

    Control Rod Hydraulic Drive Mechanism(CRHDM) is a newly invented build-in control rod drive mechanism. Hydraulic absorber is the key part of this mechanism, and is used to cushion the control rod when the rod scrams. Thus, it prevents the control rod from being deformed and damaged. In this paper dynamics program ANSYS CFX is used to calculate all kinds of flow conditions in hydraulic absorber to obtain its hydraulic characteristics. Based on the flow resistance coefficients obtained from the simulation results, fluid mass and momentum equations were developed to get the trend of pressure change in the hydraulic cylinder and the displacement of the piston rod during the buffering process of the control rod. The results obtained in this paper indicate that the hydraulic absorber meets the design requirement. The work in this paper will be helpful for the design and optimization of the control rod hydraulic absorber. (author)

  9. Evaluation of electromagnetic absorbing capacity of materials in foundry industry

    Directory of Open Access Journals (Sweden)

    D. Nowak

    2010-01-01

    Full Text Available In the paper, a research on determining the standing wave ratio as a measure of electromagnetic absorbing capacity of moulding materials is presented. Preliminary tests performed using a microwave strip line showed that high-silica, chromite and magnesite moulding sands are characterised by low absorbing capacity of microwaves. It was demonstrated that microwave absorbing capacity is significantly affected by chemical compounds included in the examined substrates. It was found that use of a microwave strip line permits precise determining characteristic microwave absorbing capacities of various moulding materials and thus their suitability for microwave drying/hardening of moulds and cores or for other foundry processes. Such a microwave drier can be applied for identifying mass components and for determining e.g. base granularity by means of precisely determined reflection ratios |Γ| and positions of minimum signal values.

  10. Development of highly effective neutron shields and neutron absorbing materials

    International Nuclear Information System (INIS)

    Tsuda, K.; Matsuda, F.; Taniuchi, H.; Yuhara, T.; Iida, T.

    1993-01-01

    A wide range of materials, including polymers and hydrogen-occluded alloys that might be usable as the neutron shielding material were examined. And a wide range of materials, including aluminum alloys that might be usable as the neutron-absorbing material were examined. After screening, the candidate material was determined on the basis of evaluation regarding its adaptabilities as a high-performance neutron-shielding and neutron-absorbing material. This candidate material was manufactured for trial, after which material properties tests, neutron-shielding tests and neutron-absorbing tests were carried out on it. The specifications of this material were thus determined. This research has resulted in materials of good performance; a neutron-shielding material based on ethylene propylene rubber and titanium hydride, and a neutron-absorbing material based on aluminum and titanium hydride. (author)

  11. Influence of absorbed pump profile on the temperature distribution ...

    Indian Academy of Sciences (India)

    2017-01-20

    -pumped laser rod is extracted. This model can be used for side-pumped laser rods whose absorbed pump profile is a Gaussian profile. Then, it is validated by numerical results which exhibit a good agreement with the ...

  12. Wind power

    International Nuclear Information System (INIS)

    Gipe, P.

    2007-01-01

    This book is a translation of the edition published in the USA under the title of ''wind power: renewable energy for home, farm and business''. In the wake of mass blackouts and energy crises, wind power remains a largely untapped resource of renewable energy. It is a booming worldwide industry whose technology, under the collective wing of aficionados like author Paul Gipe, is coming of age. Wind Power guides us through the emergent, sometimes daunting discourse on wind technology, giving frank explanations of how to use wind technology wisely and sound advice on how to avoid common mistakes. Since the mid-1970's, Paul Gipe has played a part in nearly every aspect of wind energy development from installing small turbines to promoting wind energy worldwide. As an American proponent of renewable energy, Gipe has earned the acclaim and respect of European energy specialists for years, but his arguments have often fallen on deaf ears at home. Today, the topic of wind power is cropping up everywhere from the beaches of Cape Cod to the Oregon-Washington border, and one wind turbine is capable of producing enough electricity per year to run 200 average American households. Now, Paul Gipe is back to shed light on this increasingly important energy source with a revised edition of Wind Power. Over the course of his career, Paul Gipe has been a proponent, participant, observer, and critic of the wind industry. His experience with wind has given rise to two previous books on the subject, Wind Energy Basics and Wind Power for Home and Business, which have sold over 50,000 copies. Wind Power for Home and Business has become a staple for both homeowners and professionals interested in the subject, and now, with energy prices soaring, interest in wind power is hitting an all-time high. With chapters on output and economics, Wind Power discloses how much you can expect from each method of wind technology, both in terms of energy and financial savings. The book updated models

  13. Scattering by closely spaced infinite cylinders in an absorbing medium

    Directory of Open Access Journals (Sweden)

    S.-C. Lee

    2011-09-01

    Full Text Available Scattering by closely spaced parallel infinite cylinders in an absorbing medium is considered in this paper. The source wave is arbitrarily polarized and propagates in a general direction at the cylinders. The formulation utilizes the Hertz potential approach, and the scattering cross section and intensity distribution in the far-field are developed. Numerical results are presented to illustrate the influence of the absorbing medium on the scattering properties of two configurations of closely-spaced cylinders.

  14. Sodium erosion of boron carbide from breached absorber pins

    International Nuclear Information System (INIS)

    Basmajian, J.A.; Baker, D.E.

    1981-03-01

    The purpose of the irradiation experiment was to provide an engineering demonstration of the irradiation behavior of breached boron carbide absorber pins. By building defects into the cladding of prototypic absorber pins, and performing the irradiation under typical FFTF operating conditions, a qualitative assessment of the consequences of a breach was achieved. Additionally, a direct comparison of pin behavior with that of the ex-reactor test could be made

  15. Calirimeter/absorber optimization for a RHIC dimuon experiment

    Energy Technology Data Exchange (ETDEWEB)

    Aronson, S.H.; Murtagh, M.J.; Starks, M. [Brookhaven National Lab., Upton, NY (United States); Liu, X.T.; Petitt, G.A.; Zhang, Z. [Georgia State Univ., Atlanta (United States); Ewell, L.A.; Hill, J.C.; Wohn, F.K. [Iowa State Univ., Ames (United States); Costales, J.B.; Namboodiri, M.N., Sangster, T.C.; Thomas, J.H. [Lawrence Livermore National Lab., CA (United States); Gavron, A.; Waters, L. [Los Alamos National Lab., NM (United States); Kehoe, W.L.; Steadman, S.G. [Massachusetts Institute of Technology, Cambridge (United States); Awes, T.C.; Obenshain, F.E.; Saini, S.; Young, G.R. [Oak Ridge National Lab., TN (United States); Chang, J.; Fung, S.Y.; Kang, J.H. [Univ. of California, Riverside, CA (United States); Kreke, J.; He, Xiaochun, Sorensen, S.P. [Univ. of Tennessee, Knoxville (United States); Cornell, E.C.; Maguire, C.F. [Vanderbilt Univ., Nashville, TN (United States)

    1991-12-31

    The RD-10 R&D effort on calorimeter/absorber optimization for a RHIC experiment had an extended run in 1991 using the A2 test beam at the AGS. Measurements were made of the leakage of particles behind various model hadron calorimeters. Behavior of the calorimeter/absorber as a muon-identifier was studied. First comparisons of results from test measurements to calculated results using the GHEISHA code were made

  16. DNA Infrared Absorbency Detection using Photopyroelectric Technique and FTIR Spectroscopy

    OpenAIRE

    Ebu-TEİR, Musa; Abu-TAHA, Mohammad; Al-JAMAL, Atef; EİDEH, H.

    2008-01-01

    Absorbencies of different DNA samples were studied using the well known photopyroelectric (PPE) technique and Fourier Transform Infrared (FTIR) spectrometer. In the fi rst method, wideband radiation absorbance from an infrared (IR) pulsed wideband source (PWBS) by DNA samples were detected and compared with FTIR spectrum. It was shown that the PPE technique results are useful and comparable to FTIR in distinguishing different DNA samples of biological interests

  17. The representation of absorbers in finite difference diffusion codes

    International Nuclear Information System (INIS)

    Buckler, A.N.; Tyror, J.G.

    1963-10-01

    In this paper we present a new method of representing absorbers in finite difference codes utilising the analytical flux solution in the vicinity of the absorbers. Taking an idealised reactor model, numerical comparisons are made between the finite difference eigenvalues and fluxes and results obtained from a purely analytical treatment of control rods in a reactor (the Codd-Rennie method), and agreement is found to be encouraging. The method has been coded for the IBM7090. (author)

  18. Neutron absorbing room temperature vulcanizable silicone rubber compositions

    International Nuclear Information System (INIS)

    Zoch, H.L.

    1979-01-01

    A neutron absorbing composition is described and consists of a one-component room temperature vulcanizable silicone rubber composition or a two-component room temperature vulcanizable silicone rubber composition in which the composition contains from 25 to 300 parts by weight based on the base silanol or vinyl containing diorganopolysiloxane polymer of a boron compound or boron powder as the neutron absorbing ingredient. An especially useful boron compound in this application is boron carbide. 20 claims

  19. On (m, n)-absorbing ideals of commutative rings

    Indian Academy of Sciences (India)

    Abstract. Let R be a commutative ring with 1 = 0 and U(R) be the set of all unit elements of R. Let m, n be positive integers such that m > n. In this article, we study a generalization of n-absorbing ideals. A proper ideal I of R is called an (m, n)- absorbing ideal if whenever a1 ··· am ∈ I for a1,...,am ∈ R \\ U(R), then there are n.

  20. Cost-Based Design and Selection of Point Absorber Devices for the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Vincenzo Piscopo

    2018-04-01

    Full Text Available Sea wave energy is one of the most promising renewable sources, even if relevant technology is not mature enough for the global energy market and is not yet competitive if compared with solar, wind and tidal current devices. Particularly, among the variety of wave energy converters developed in the last decade, heaving point absorbers represent one of the most feasible and studied technologies, as shown by the small-scale testing and full-scale prototypes, deployed in the last years throughout the world. Nevertheless, the need for further reduction of the energy production costs requires a specialized design of wave energy converters, accounting for the restraints provided by the power take-off unit and the device operational profile. Hence, actual analysis focuses on a new cost-based design procedure for heaving point absorbers. The device is equipped with a floating buoy with an optional fully submerged mass connected, by means of a tensioned line, to the power take-off unit. It consists of a permanent magnet linear generator, lying on the seabed and equipped with a gravity-based foundation. The proposed procedure is applied to several candidate deployment sites located in the Mediterranean Sea; the incidence of the power take-off restraint and the converter operational profile is fully investigated and some recommendations for preliminary design of wave energy converter devices are provided. Current results show that there is wide scope to make the wave energy sector more competitive on the international market, by properly selecting the main design parameters of point absorbers, on the basis of met-ocean conditions at the deployment site.

  1. Expected Business Conditions and Bond Risk Premia

    DEFF Research Database (Denmark)

    Eriksen, Jonas Nygaard

    This paper studies the predictability of bond risk premia by means of expectations to future business conditions using survey forecasts from the Survey of Professional Forecasters. We show that expected business conditions consistently affect excess bond returns and that the inclusion of expected...

  2. Master's degree studies: Expectations versus reality | Swanepoel ...

    African Journals Online (AJOL)

    In this article, I discuss to what extent the expectations of government, universities as provider institutions, and students as clients are reconcilable regarding master's degree studies. I also consider the position of the lecturer, who is expected to produce whilst being caught between the expectations of these stakeholders.

  3. High Performance Expectations: Concept and causes

    DEFF Research Database (Denmark)

    Andersen, Lotte Bøgh; Jacobsen, Christian Bøtcher

    2017-01-01

    High performance expectations (HPE) are central in public management because employees tend to contribute more when their leaders have high expectations to them. However, we know little about how leaders make it clear to employees that they have these high expectations. Building on transformation...

  4. Measuring Risk When Expected Losses Are Unbounded

    Directory of Open Access Journals (Sweden)

    Alejandro Balbás

    2014-09-01

    Full Text Available This paper proposes a new method to introduce coherent risk measures for risks with infinite expectation, such as those characterized by some Pareto distributions. Extensions of the conditional value at risk, the weighted conditional value at risk and other examples are given. Actuarial applications are analyzed, such as extensions of the expected value premium principle when expected losses are unbounded.

  5. Neutron absorbing article and method for manufacture of such article

    International Nuclear Information System (INIS)

    Hortman, M.T.; Mcmurtry, C.H.; Naum, R.G.; Owens, D.P.

    1980-01-01

    A neutron absorbing article, preferably in long, thin, flat form , suitable for but not necessarily limited to use in storage racks for spent nuclear fuel at locations between volumes of such stored fuel, to absorb neutrons from said spent fuel and prevent uncontrolled nuclear reaction of the spent fuel material, is composed of finely divided boron carbide particles and a solid, irreversibly cured phenolic polymer, forming a continuous matrix about the boron carbide particles, in such proportions that at least 6% of b10 from the boron carbide content is present therein. The described articles withstand thermal cycling from repeated spent fuel insertions and removals, withstand radiation from said spent nuclear fuel over long periods of time without losing desirable neutron absorbing and physical properties, are sufficiently chemically inert to water so as to retain neutron absorbing properties if brought into contact with it, are not galvanically corrodible and are sufficiently flexible so as to withstand operational basis earthquake and safe shutdown earthquake seismic events, without loss of neutron absorbing capability and other desirable properties, when installed in storage racks for spent nuclear fuel. The disclosure also relates to a plurality of such neutron absorbing articles in a storage rack for spent nuclear fuel and to a method for the manufacture of the articles

  6. Urea Rebound Assessment Based on UV Absorbance in Spent Dialysate.

    Science.gov (United States)

    Tomson, Ruth; Uhlin, Fredrik; Fridolin, Ivo

    2014-01-01

    The aim of the study was to examine the possibility of postdialysis urea rebound assessment using UV-absorbance measurements in spent dialysate. Twenty-six patients on chronic three-times-a-week hemodialysis (HD) were studied in two separate studies. Double-beam spectrophotometer was used for the determination of UV absorbance in the collected spent dialysate samples. Also, on-line UV absorbance was monitored. The equilibrium concentration (C(eq)) of urea at the end of the rebound phase was calculated based on urea concentration in blood and dialysate and UV absorbance in spent dialysate. Based on C(eq), urea rebound was expressed relative to urea concentration at the end of HD (R1) and relative to the decrease in urea concentration during HD (R2). Estimates based on UV-absorbance values in spent dialysate (R(1_a), R(2_a)) slightly over assess postdialysis rebound compared with results based on the blood sample drawn 30 min after HD (R(1_30post), R(2_30post)), but R(1_a) and R(2_a) presented greater consistency and accuracy compared with the estimates based on the intradialytic blood sample (R(1_b), R(2_b)). In summary, the results show that it is possible to assess postdialysis urea rebound in blood based on UV-absorbance measurements in spent dialysate.

  7. Comparison of absorbed doses resulting from various intraoral periapical radiography

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Mi Ae; Park, Tae Won [Dept. of Oral and Maxillofacial Radiology, Graduate School, Seoul National University, Seoul (Korea, Republic of)

    1995-08-15

    This study was designed to measure the absorbed dose to organs of special interest from full mouth with intraoral film (14 films) and to compare the five periapical techniques. Thermoluminescent crystals (TLD-100 chip) were located in brain, orbit, bone marrow of mandibular ramus, bone marrow of mandibular body, bone marrow of 4th cervical spine, parotid gland, submandibular gland and thyroid gland. X-ray machine was operated at 70 kVp and round collimating film holding device (XCP) and rectangular collimating film holding device (Precision Instrument) were used. The distance from the X-ray focus to the open end of the collimator was 8 inch, 12 inch and 16 inch. The following results obtained; 1. The absorbed dose was the highest in bone marrow of mandibular body (5.656 mGy) and the lowest in brain (0.050 mGy). 2. Generally, the lowest absorbed dose was measured from 16 inch cylinder, rectangular collimating film holding device with paralleling technique. But, in bone marrow of mandibular body and the floor of mouth, the highest absorbed dose was measured from 12 inch cylinder, rectangular collimating film holding device with paralleling techniques. 3. Comparing of five intraoral radiographic techniques, it was appeared statistically significant reduction of the absorbed doses measured with rectangualr collimating film holding device compared to XCP film holding device (p<0.05). 4. No statistically significant reduction in the absorbed dose was found as cylinder length was change (p>0.05).

  8. A Stretchable Electromagnetic Absorber Fabricated Using Screen Printing Technology.

    Science.gov (United States)

    Jeong, Heijun; Lim, Sungjoon

    2017-05-21

    A stretchable electromagnetic absorber fabricated using screen printing technology is proposed in this paper. We used a polydimethylsiloxane (PDMS) substrate to fabricate the stretchable absorber since PDMS exhibits good dielectric properties, flexibility, and restoring capabilities. DuPont PE872 (DuPont, Wilmington, CT, USA), a stretchable silver conductive ink, was used for the screen printing technique. The reflection coefficient of the absorber was measured using a vector network analyzer and a waveguide. The proposed absorber was designed as a rectangular patch unit cell, wherein the top of the unit cell acted as the patch and the bottom formed the ground. The size of the patch was 8 mm × 7 mm. The prototype of the absorber consisted of two unit cells such that it fits into the WR-90 waveguide (dimensions: 22.86 mm × 10.16 mm) for experimental measurement. Before stretching the absorber, the resonant frequency was 11 GHz. When stretched along the x -direction, the resonant frequency shifted by 0.1 GHz, from 11 to 10.9 GHz, demonstrating 99% absorption. Furthermore, when stretched along the y -direction, the resonant frequency shifted by 0.6 GHz, from 11 to 10.4 GHz, demonstrating 99% absorption.

  9. A switchable dual-wavelength erbium-doped fiber laser based on saturable absorber and active optical fiber ring filter

    Science.gov (United States)

    Zhu, Lian-qing; Chen, Qing-shan; Zhao, Ran-ran; Lou, Xiao-ping; He, Wei

    2014-11-01

    A dual-wavelength erbium-doped fiber laser (EDFL) with outstanding stability is presented. In the fiber laser system, two nested active optical fiber ring filters are configured to improve the comb spectrum performance, a saturable absorber is employed to form a gain grating for both filtering and frequency stabilizing, two cascaded fiber Bragg gratings (FBGs) are utilized to achieve dual-wavelength output, and a variable attenuator is arranged to adjust output power. Experimental results illustrate that the peak wavelength drift is less than 3 pm, and a good linear relationship between output power and pump power is realized.

  10. Expectations affect psychological and neurophysiological benefits even after a single bout of exercise.

    Science.gov (United States)

    Mothes, Hendrik; Leukel, Christian; Jo, Han-Gue; Seelig, Harald; Schmidt, Stefan; Fuchs, Reinhard

    2017-04-01

    The study investigated whether typical psychological, physiological, and neurophysiological changes from a single exercise are affected by one's beliefs and expectations. Seventy-six participants were randomly assigned to four groups and saw different multimedia presentations suggesting that the subsequent exercise (moderate 30 min cycling) would result in more or less health benefits (induced expectations). Additionally, we assessed habitual expectations reflecting previous experience and beliefs regarding exercise benefits. Participants with more positive habitual expectations consistently demonstrated both greater psychological benefits (more enjoyment, mood increase, and anxiety reduction) and greater increase of alpha-2 power, assessed with electroencephalography. Manipulating participants' expectations also resulted in largely greater increases of alpha-2 power, but not in more psychological exercise benefits. On the physiological level, participants decreased their blood pressure after exercising, but this was independent of their expectations. These results indicate that habitual expectations in particular affect exercise-induced psychological and neurophysiological changes in a self-fulfilling manner.

  11. Analysis of Urban Forest Needs as Anthropogenic (CO2) Gas Absorbent in Semarang City

    Science.gov (United States)

    Febriani, Anisa Putri; Retnaningsih Soeprobowati, Tri; Maryono

    2018-02-01

    Green open space in cities in significant needs to maintenance environment quality. On of the critical function is to absorb increasing number of gas CO2. Therefore, developing urban forest in cities is very importance. The objective of the study is to determine the area of urban forest as CO2 gas anthropogenic absorb which is formed from fuel, diesel fuel, liquid petroleum gas. The study consists of (1) Analyzing the number of CO2 gas emission by calculating the needs of petroleum and gas based on the number of population, (2) Analyzing the power of gas absorption, (3) Measuring the air concentration of CO2 gas ambient based on daily traffic activities. This study shown that from year 2013 to year 2017, the increasing of urban forest is not so significant. For year 2013 the green open space in Semarang City are 373.67 hectares (7.5 percent from Semarang City area), consists of 239 parks, 11 public cemeteries, production forests, community forests, and urban forests, however the area of urban forest is not increase. The study assess that Antidesmabunius is one of the green species which high absorb capacity planted for Semarang. This trees produce 31,31 ton annually. This study proposed to fostering Antidesmabunius as one principle threes in Semarang urban forest.

  12. Fast-response cryogenic calorimeter containing a 52-KG radiation absorber

    International Nuclear Information System (INIS)

    Bendt, P.J.; Yarnell, J.L.

    1977-01-01

    An isothermal liquid helium boiloff calorimeter containing a 52-kg copper radiation absorber, and having a time constant 235 U foils irradiated in a nuclear reactor. The short response time was achieved by the large reduction in heat capacity of solids at 4 0 K, and by nearly isothermal operation. Though the initial power level was approx.3 W, the maximum thermal energy storage was approx.1 joule. The Al clad foils were transported in approx.1 s, and cooled to liquid helium temperature in approx.3 s. Boil-off helium gas was warmed to room temperature in a controlled manner, and measured with a hot-film anemometer flowmeter, which was calibrated by comparison with a dry-test volume flowmeter, and by electric heating of the radiation absorber. The correction for gamma leakage from the absorber was less than or equal to 3%, and the correction at short cooling times for sample cooldown, 2.24-m activity of the Al cladding, and system response time, amounted to 3.4% at 10 s. The overall accuracy (1 sigma) of the radiation measurements is less than or equal to 2%, except at the shortest cooling time (10 s), where it rises to 4%

  13. V3+:YAG as the saturable absorber for a diode-pumped quasi-three-level dual-wavelength Nd:GGG laser.

    Science.gov (United States)

    Huang, Hai-Tao; He, Jing-Liang; Zhang, Bai-Tao; Yang, Jian-Fei; Xu, Jin-Long; Zuo, Chun-Hua; Tao, Xu-Tang

    2010-02-15

    The performance of a diode-end-pumped passively Q-switched dual-wavelength Nd:GGG laser operating at 932.9 and 936.5 nm with V(3+):YAG as the saturable absorber was demonstrated for the first time to the best of our knowledge. The maximum dual-wavelength average output power of 150 mW was achieved with a T = 2% output coupler under the absorbed pump power of 2.55 W, corresponding to the optical-to-optical conversion and slope efficiency of 5.9% and 8.0%, respectively. The minimum pulse width was 395 ns with the pulse repetition frequency of 140 kHz, which was attained with a T = 5% output coupler under the absorbed pump power of 2.55 W.

  14. Expectation of recovery from low back pain

    DEFF Research Database (Denmark)

    Kongsted, Alice; Vach, Werner; Axø, Marie

    2014-01-01

    participants completed questionnaires at their first consultation due to LBP and 78% were followed for 3 months. At baseline, recovery expectations were measured on a 0-10 scale. Outcome measures were LBP intensity and Global Perceived Effect (GPE). Associations were tested in regression models......Study Design. A prospective cohort study conducted in general practice (GP) and chiropractic practice (CP).Objectives. To explore which patient characteristics were associated with recovery expectations in low back pain (LBP) patients, whether expectations predicted 3-month outcome, and to what...... extent expectations were associated with empirical prognostic factors.Summary of Background Data. Patients' recovery expectations have been associated with prognosis, but it is largely unknown why patients expect what they do, and how expectations relate to other prognostic factors.Methods. 1169...

  15. A multicenter randomized controlled trial comparing absorbable barbed sutures versus conventional absorbable sutures for dermal closure in open surgical procedures.

    Science.gov (United States)

    Rubin, J Peter; Hunstad, Joseph P; Polynice, Alain; Gusenoff, Jeffrey A; Schoeller, Thomas; Dunn, Raymond; Walgenbach, Klaus J; Hansen, Juliana E

    2014-02-01

    Barbed sutures were developed to reduce operative time and improve security of wound closure. The authors compare absorbable barbed sutures (V-Loc, Covidien, Mansfield, Massachusetts) with conventional (smooth) absorbable sutures for soft tissue approximation. A prospective multicenter randomized study comparing barbed sutures with smooth sutures was undertaken between August 13, 2009, and January 31, 2010, in 241 patients undergoing abdominoplasty, mastopexy, and reduction mammaplasty. Each patient received barbed sutures on 1 side of the body, with deep dermal sutures eliminated or reduced. Smooth sutures with deep dermal and subcuticular closure were used on the other side as a control. The primary endpoint was dermal closure time. Safety was assessed through adverse event reporting through a 12-week follow-up. A total of 229 patients were ultimately treated (115 with slow-absorbing polymer and 114 with rapid-absorbing polymer). Mean dermal closure time was significantly quicker with the barbed suture compared with the smooth suture (12.0 vs 19.2 minutes; P<.001), primarily due to the need for fewer deep dermal sutures. The rapid-absorbing barbed suture showed a complication profile equivalent to the smooth suture, while the slow-absorbing barbed suture had a higher incidence of minor suture extrusion. Barbed sutures enabled faster dermal closure quicker than smooth sutures, with a comparable complication profile. 1.

  16. Diamond detector in absorbed dose measurements in high-energy linear accelerator photon and electron beams.

    Science.gov (United States)

    Ravichandran, Ramamoorthy; Binukumar, John Pichy; Al Amri, Iqbal; Davis, Cheriyathmanjiyil Antony

    2016-03-08

    Diamond detectors (DD) are preferred in small field dosimetry of radiation beams because of small dose profile penumbras, better spatial resolution, and tissue-equivalent properties. We investigated a commercially available 'microdiamond' detector in realizing absorbed dose from first principles. A microdiamond detector, type TM 60019 with tandem electrometer is used to measure absorbed doses in water, nylon, and PMMA phantoms. With sensitive volume 0.004 mm3, radius 1.1mm, thickness 1 x10(-3) mm, the nominal response is 1 nC/Gy. It is assumed that the diamond detector could collect total electric charge (nC) developed during irradiation at 0 V bias. We found that dose rate effect is less than 0.7% for changing dose rate by 500 MU/min. The reproducibility in obtaining readings with diamond detector is found to be ± 0.17% (1 SD) (n = 11). The measured absorbed doses for 6 MV and 15 MV photons arrived at using mass energy absorption coefficients and stop-ping power ratios compared well with Nd, water calibrated ion chamber measured absorbed doses within 3% in water, PMMA, and nylon media. The calibration factor obtained for diamond detector confirmed response variation is due to sensitivity due to difference in manufacturing process. For electron beams, we had to apply ratio of electron densities of water to carbon. Our results qualify diamond dosimeter as a transfer standard, based on long-term stability and reproducibility. Based on micro-dimensions, we recommend these detectors for pretreatment dose verifications in small field irradiations like stereotactic treatments with image guidance.

  17. Hydraulic power take-off for wave energy systems

    DEFF Research Database (Denmark)

    Christensen, Georg Kronborg

    2001-01-01

    Investigation and laboratory experiments with a hydraulic power conversion system for converting forces from a 2.5m diamter float to extract energy from seawaves. The test rig consists of a hydraulic wave simulator and a hydraulic point absorber. The absorber converts the incomming forces...

  18. Considering linear generator copper losses on model predictive control for a point absorber wave energy converter

    International Nuclear Information System (INIS)

    Montoya Andrade, Dan-El; Villa Jaén, Antonio de la; García Santana, Agustín

    2014-01-01

    Highlights: • We considered the linear generator copper losses in the proposed MPC strategy. • We maximized the power transferred to the generator side power converter. • The proposed MPC increases the useful average power injected into the grid. • The stress level of the PTO system can be reduced by the proposed MPC. - Abstract: The amount of energy that a wave energy converter can extract depends strongly on the control strategy applied to the power take-off system. It is well known that, ideally, the reactive control allows for maximum energy extraction from waves. However, the reactive control is intrinsically noncausal in practice and requires some kind of causal approach to be applied. Moreover, this strategy does not consider physical constraints and this could be a problem because the system could achieve unacceptable dynamic values. These, and other control techniques have focused on the wave energy extraction problem in order to maximize the energy absorbed by the power take-off device without considering the possible losses in intermediate devices. In this sense, a reactive control that considers the linear generator copper losses has been recently proposed to increase the useful power injected into the grid. Among the control techniques that have emerged recently, the model predictive control represents a promising strategy. This approach performs an optimization process on a time prediction horizon incorporating dynamic constraints associated with the physical features of the power take-off system. This paper proposes a model predictive control technique that considers the copper losses in the control optimization process of point absorbers with direct drive linear generators. This proposal makes the most of reactive control as it considers the copper losses, and it makes the most of the model predictive control, as it considers the system constraints. This means that the useful power transferred from the linear generator to the power

  19. Control of base-excited dynamical systems through piezoelectric energy harvesting absorber

    Science.gov (United States)

    Abdelmoula, H.; Dai, H. L.; Abdelkefi, A.; Wang, L.

    2017-09-01

    The spring-mass absorber usually offers a good control to dynamical systems under direct base excitations for a specific value of the excitation frequency. As the vibrational energy of a primary dynamical system is transferred to the absorber, it gets dissipated. In this study, this energy is no longer dissipated but converted to available electrical power by designing efficient energy harvesters. A novel design of a piezoelectric beam installed inside an elastically-mounted dynamical system undergoing base excitations is considered. A design is carried out in order to determine the properties and dimensions of the energy harvester with the constraint of simultaneously decreasing the oscillating amplitudes of the primary dynamical system and increasing the harvested power of the energy harvesting absorber. An analytical model for the coupled system is constructed using Euler-Lagrange principle and Galerkin discretization. Different strategies for controlling the primary structure displacement and enhancing the harvested power as functions of the electrical load resistance and thickness of the beam substrate are performed. The linear polynomial approximation of the system’s key parameters as a function of the beam’s substrate thickness is first carried out. Then, the gradient method is applied to determine the adequate values of the electrical load resistance and thickness of the substrate under the constraints of minimizing the amplitudes of the primary structure or maximizing the levels of the harvested power. After that, an iterative strategy is considered in order to simultaneously minimize the amplitudes of the primary structure and maximize the levels of the harvested power as functions of the thickness of the substrate and electrical load resistance. In addition to harmonic excitations, the coupled system subjected to a white noise is explored. Through this analysis, the load resistance and thickness of the substrate of the piezoelectric energy harvester

  20. Specification of absorbed dose for reporting a therapeutic irradiation

    International Nuclear Information System (INIS)

    Wambersie, A.; Chassagne, D.

    1981-01-01

    The problem of dose specification in external beam therapy with photons and electrons has been dealt with in ICRU Report 29 (1978). This problem arises from the fact that the absorbed dose distribution is usually not uniform in the target volume and that for the purpose of treatment reporting a nominal absorbed dose - which will be called target absorbed dose - has to be selected. When comparing the clinical results obtained between radiotherapy centres, the differences in the reported target absorbed doses which can be introduced by differences in the methods of dose specification often are much larger than the differences related to the dosimetric procedures themselves. This shows the importance of the problem. In this paper, some definitions of terms and concepts currently used in radiotherapy are first recalled: tumour volume, target volume, treatment volume, etc. These definitions have been proposed in ICRU Report 29 for photon and electron beams; they can be extended to any kind of irradiation. For external beam therapy with photons and electrons, the target absorbed dose is defined as the absorbed dose at selected point(s) (specification point(s)) having a meaningful relation to the target volume and/or the irradiation beams. Examples are discussed for typical cases. As far as interstitial and intracavitary therapy is concerned, the problem is more complex and no recommendations have so far been made by the ICRU Commission. A major difficulty arises from the sharp dose gradient as a function of the distance to the sources. The particular case of the treatment of cervix carcinoma is considered and some possible methods of specification are discussed: (1) the indication of the sources (in adequate units) and the duration of the application, (2) the absorbed doses at selected reference points (bladder, rectum, bony structures) and (3) the description of the tissue volume (height, width, thickness) encompassed by a given isodose surface (60Gy). (author)

  1. Optimum design of composite panel with photovoltaic-thermo module. Absorbing effect of cooling panel; Hikari netsu fukugo panel no saiteki sekkei. Reikyaku panel no kyunetsu koka

    Energy Technology Data Exchange (ETDEWEB)

    Sato, M.; Kikuchi, S.; Tani, T. [Science University of Tokyo, Tokyo (Japan); Kadotani, K.; Imaizumi, H. [Komatsu Ltd., Tokyo (Japan)

    1996-10-27

    The composite panel with photovoltaic-thermo module becomes higher in energy-saving than the conventional air-conditioning system by the independent radiational heating and cooling effect obtained when the generating panel using a solar cell module is combined with the heating and cooling panel using a thermo-element module. The output of a solar cell module can be directly used because the solar cell module operates in AC. This paper reports the relation between the absorbed value and power consumption of the cooling panel, while paying attention to the cooling panel. The performance coefficient of the maximum absorbed value from an non-absorbing substance to a cooling panel is 2 to 3. Assume that the cooling panel during non-adiabatic operation is operated using a solar cell module of 800 W/m{sup 2} in solar intensity and 15% in conversion efficiency. The cooling-surface temperature difference is 12.12 K, and the maximum absorbed value of a non-absorbing substance to a cooling panel is 39.12 W/m{sup 2}. The absorbed value of the outer temperature to the cooling panel is 74.4 W/m{sup 2}, and each performance coefficient is 3.26 and 0.62. The absorbed value must be calculated for evaluation from the cooling-surface temperature difference measured directly from the cooling panel. 4 refs., 8 figs., 1 tab.

  2. Worker expectations of occupational health consultations.

    Science.gov (United States)

    Stilz, R; Madan, I

    2014-04-01

    Worker beliefs and expectations influence their health and rehabilitation. However, little is known about worker expectations of occupational health (OH) consultations and if these are associated with their perceptions of health and work. To examine worker expectations of OH consultations, and whether the variability of worker expectations is associated with their perception of health and work and personal characteristics. A questionnaire on OH physicians' professional standards was developed from national guidance and validated by a survey of OH physicians. We explored 81 workers' expectations of professional standards along with their perception of health and work. Worker expectations were compared with the OH physician validation score. Associations of worker characteristics, their health and work perceptions and their expectations of professional standards were analysed by linear regression. Worker expectations of professional standards were lower when compared with the OH physician validation score (E = 3.9 versus 4.3, ΔE = 0.48, 95% confidence interval [CI] 0.30-0.66). Perceived manager support and work apprehension were associated with worker expectations (ΔE = 0.58, 95% CI: 0.29-0.86 for least versus most support; ΔE = 0.89, 95% CI: 0.41-1.36 for least versus highest apprehension). Job title, previous OH consultations and recovery expectations were not associated with worker expectations. Worker expectations of OH physicians' professional standards were lower than the standards set by national guidance as validated by the sampled OH physicians. Workers who felt more supported by their manager, and workers who were more apprehensive about the health impact of work had higher expectations of OH physicians' standards.

  3. Stock Market Expectations of Dutch Households.

    Science.gov (United States)

    Hurd, Michael; van Rooij, Maarten; Winter, Joachim

    2011-04-01

    Despite its importance for the analysis of life-cycle behavior and, in particular, retirement planning, stock ownership by private households is poorly understood. Among other approaches to investigate this puzzle, recent research has started to elicit private households' expectations of stock market returns. This paper reports findings from a study that collected data over a two-year period both on households' stock market expectations (subjective probabilities of gains or losses) and on whether they own stocks. We document substantial heterogeneity in financial market expectations. Expectations are correlated with stock ownership. Over the two years of our data, stock market prices increased, and expectations of future stock market price changes also increased, lending support to the view that expectations are influenced by recent stock gains or losses.

  4. Stochastic Dominance under the Nonlinear Expected Utilities

    Directory of Open Access Journals (Sweden)

    Xinling Xiao

    2014-01-01

    Full Text Available In 1947, von Neumann and Morgenstern introduced the well-known expected utility and the related axiomatic system (see von Neumann and Morgenstern (1953. It is widely used in economics, for example, financial economics. But the well-known Allais paradox (see Allais (1979 shows that the linear expected utility has some limitations sometimes. Because of this, Peng proposed a concept of nonlinear expected utility (see Peng (2005. In this paper we propose a concept of stochastic dominance under the nonlinear expected utilities. We give sufficient conditions on which a random choice X stochastically dominates a random choice Y under the nonlinear expected utilities. We also provide sufficient conditions on which a random choice X strictly stochastically dominates a random choice Y under the sublinear expected utilities.

  5. Speed of vision depends on temporal expectancy

    DEFF Research Database (Denmark)

    Vangkilde, Signe Allerup; Bundesen, Claus

    2009-01-01

    Temporal expectations play an important role in optimizing future perception and behavior, but the nature of the attentional processes affected by our expectations is still widely debated. To investigate effects of expectations on the speed of visual processing, we employed a cued single-letter r......Temporal expectations play an important role in optimizing future perception and behavior, but the nature of the attentional processes affected by our expectations is still widely debated. To investigate effects of expectations on the speed of visual processing, we employed a cued single......-letter recognition task with stimuli of varied durations terminated by pattern masks. To obtain an estimate of processing speed unconfounded by motor components, we used accuracy-based measures rather than reaction times. Eight healthy young subjects completed a total of 4,000 trials each. A symbolic cue...... measured the processing speed at times t [[gt

  6. Mental health expectancy--the European perspective

    DEFF Research Database (Denmark)

    Jagger, C; Ritchie, K; Brønnum-Hansen, Henrik

    1998-01-01

    The increase in life expectancy observed over the last decade has particular relevance for mental health conditions of old age, such as dementia. Although mental disorders have been estimated to be responsible for 60% of all disabilities, until recently population health indicators such as health...... expectancies have concentrated on calculating disability-free life expectancy based on physical functioning. In 1994, a European Network for the Calculation of Health Expectancies (Euro-REVES) was established, one of its aims being the development and promotion of mental health expectancies. Such indicators...... may have an important role in monitoring future changes in the mental health of populations and predicting service needs. This article summarizes the proceedings and recommendations of the first European Conference on Mental Health Expectancy....

  7. Are bio-absorbable stents the future of SFA treatment?

    Science.gov (United States)

    Peeters, P; Keirse, K; Verbist, J; Deloose, K; Bosiers, M

    2010-02-01

    Several limitations inherent to the implantation of a metallic device, such as the occurrence of in-stent re-stenosis, in an arterial lumen intuitively explain the interest for developing bio-absorbable stents. Two main types of bio-absorbable stents currently exist: polymer stents and metallic stents. To date, no studies with bio-absorbable stents have been conducted in the superficial femoral artery (SFA). Because of their strut thickness and lack of radial force, polymer stents are no good candidates for endovascular use. Absorbable metal stents (AMS) do have the potential to perform well for artery treatment, although current evidence from in-human coronary and infrapopliteal studies yield unsatisfactory results. Drastic technological improvements are mandatory before AMS can be considered for every day practice. Yet, it is our belief that further development of other metal and non-metal bio-absorbable stents, with or without drug-coating, may lead to the creation of the ultimate SFA stent.

  8. Improvement of discontinuity factor for strong absorber region

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Jiong, E-mail: guojiong12@mail.tsinghua.edu.cn; Li, Fu, E-mail: lifu@mail.tsinghua.edu.cn; Zhang, Han; Zhou, Xiafeng; Fan, Kai; Wang, Lidong; Lu, Jianan

    2016-09-15

    At Institute of Nuclear and New Energy Technology (INET) the discontinuity factor corrected diffusion method with the homogenization technology was developed and applied in the control rod worth calculation of the pebble bed high temperature gas cooled reactor. But the result with the normal procedure is not accurate enough for a strong absorber. The numerical analysis shows that the strong absorber still has great influence on the flux distribution in the nearby graphite region, so that the flux distribution obtained by the normal diffusion method does not agree with the transport result. Thus, two improvements were proposed in this paper. First, instead of the neutron flux in the middle of the fine mesh, the surface flux of the absorber region was calculated through the net current in the boundary of the region; and then, while the discontinuity factor of the homogenized absorber region should be calculated, the discontinuity factor of the neighboring graphite region on the other side of the interface should also be calculated to eliminate the influence of the strong absorber. The numerical results demonstrate that, based on the improved method, the accuracy of heterogeneous transport calculation can be achieved by a diffusion calculation.

  9. Robust optimization of a tandem grating solar thermal absorber

    Science.gov (United States)

    Choi, Jongin; Kim, Mingeon; Kang, Kyeonghwan; Lee, Ikjin; Lee, Bong Jae

    2018-04-01

    Ideal solar thermal absorbers need to have a high value of the spectral absorptance in the broad solar spectrum to utilize the solar radiation effectively. Majority of recent studies about solar thermal absorbers focus on achieving nearly perfect absorption using nanostructures, whose characteristic dimension is smaller than the wavelength of sunlight. However, precise fabrication of such nanostructures is not easy in reality; that is, unavoidable errors always occur to some extent in the dimension of fabricated nanostructures, causing an undesirable deviation of the absorption performance between the designed structure and the actually fabricated one. In order to minimize the variation in the solar absorptance due to the fabrication error, the robust optimization can be performed during the design process. However, the optimization of solar thermal absorber considering all design variables often requires tremendous computational costs to find an optimum combination of design variables with the robustness as well as the high performance. To achieve this goal, we apply the robust optimization using the Kriging method and the genetic algorithm for designing a tandem grating solar absorber. By constructing a surrogate model through the Kriging method, computational cost can be substantially reduced because exact calculation of the performance for every combination of variables is not necessary. Using the surrogate model and the genetic algorithm, we successfully design an effective solar thermal absorber exhibiting a low-level of performance degradation due to the fabrication uncertainty of design variables.

  10. Comparison of absorbed doses resulting from various intraoral periapical radiography

    International Nuclear Information System (INIS)

    Kang, Mi Ae; Park, Tae Won

    1995-01-01

    This study was designed to measure the absorbed dose to organs of special interest from full mouth with intraoral film (14 films) and to compare the five periapical techniques. Thermoluminescent crystals (TLD-100 chip) were located in brain, orbit, bone marrow of mandibular ramus, bone marrow of mandibular body, bone marrow of 4th cervical spine, parotid gland, submandibular gland and thyroid gland. X-ray machine was operated at 70 kVp and round collimating film holding device (XCP) and rectangular collimating film holding device (Precision Instrument) were used. The distance from the X-ray focus to the open end of the collimator was 8 inch, 12 inch and 16 inch. The following results obtained; 1. The absorbed dose was the highest in bone marrow of mandibular body (5.656 mGy) and the lowest in brain (0.050 mGy). 2. Generally, the lowest absorbed dose was measured from 16 inch cylinder, rectangular collimating film holding device with paralleling technique. But, in bone marrow of mandibular body and the floor of mouth, the highest absorbed dose was measured from 12 inch cylinder, rectangular collimating film holding device with paralleling techniques. 3. Comparing of five intraoral radiographic techniques, it was appeared statistically significant reduction of the absorbed doses measured with rectangualr collimating film holding device compared to XCP film holding device (p 0.05).

  11. Inferring absorbing organic carbon content from AERONET data

    Directory of Open Access Journals (Sweden)

    A. Arola

    2011-01-01

    Full Text Available Black carbon, light-absorbing organic carbon (often called "brown carbon" and mineral dust are the major light-absorbing aerosols. Currently the sources and formation of brown carbon aerosol in particular are not well understood. In this study we estimated the amount of light–absorbing organic carbon and black carbon from AERONET measurements. We find that the columnar absorbing organic carbon (brown carbon levels in biomass burning regions of South America and Africa are relatively high (about 15–20 mg m−2 during biomass burning season, while the concentrations are significantly lower in urban areas in US and Europe. However, we estimated significant absorbing organic carbon amounts from the data of megacities of newly industrialized countries, particularly in India and China, showing also clear seasonality with peak values up to 30–35 mg m−2 during the coldest season, likely caused by the coal and biofuel burning used for heating. We also compared our retrievals with the modeled organic carbon by the global Oslo CTM for several sites. Model values are higher in biomass burning regions than AERONET-based retrievals, while the opposite is true in urban areas in India and China.

  12. Inferring absorbing organic carbon content from AERONET data

    Science.gov (United States)

    Arola, A.; Schuster, G.; Myhre, G.; Kazadzis, S.; Dey, S.; Tripathi, S. N.

    2011-01-01

    Black carbon, light-absorbing organic carbon (often called "brown carbon") and mineral dust are the major light-absorbing aerosols. Currently the sources and formation of brown carbon aerosol in particular are not well understood. In this study we estimated the amount of light-absorbing organic carbon and black carbon from AERONET measurements. We find that the columnar absorbing organic carbon (brown carbon) levels in biomass burning regions of South America and Africa are relatively high (about 15-20 mg m-2 during biomass burning season), while the concentrations are significantly lower in urban areas in US and Europe. However, we estimated significant absorbing organic carbon amounts from the data of megacities of newly industrialized countries, particularly in India and China, showing also clear seasonality with peak values up to 30-35 mg m-2 during the coldest season, likely caused by the coal and biofuel burning used for heating. We also compared our retrievals with the modeled organic carbon by the global Oslo CTM for several sites. Model values are higher in biomass burning regions than AERONET-based retrievals, while the opposite is true in urban areas in India and China.

  13. Study on 'Tannix' an absorbent for heavy metals including uranium

    International Nuclear Information System (INIS)

    Nakamura, Yasuo

    1997-01-01

    To treat radioactive wastes including uranium and transuranic elements such as plutonium, americium etc., development of an absorbent which can be used to absorb and isolate these elements without producing secondary wastes after treatment was attempted. And an absorbent has been successfully developed by polymerizing tannin, a natural product. It is known that tannin binds heavy metals including uranium resulting to produce their precipitates. There are some reports suggesting its absorption ability for uranium. However, tannin has not been used to isolate a heavy metal from a solution because it is soluble in water. Here, insolubilization of tannin was attempted and a manufacturing method for a gelatinized insoluble tannin named as ''Tannix'' was established. Wattle tannin extracted from Mimosa pudica produced in Africa was dissolved in an alkaline solution and gelatinized by heating after the addition of formalin. Thus obtained insoluble tannin was used after crushing and sieving. This product, ''Tannix'' was able to absorb more than 99% of uranium in the waste. And the absorbed Tannin could be degraded by incineration even at a low temperature, leaving only uranium, but not producing any secondary product. (M.N.)

  14. Energy Analysis of Solar Collector With perforated Absorber Plate

    Directory of Open Access Journals (Sweden)

    Ammar A. Farhan

    2017-09-01

    Full Text Available The thermal performance of three solar collectors with 3, 6 mm and without perforation absorber plate was assessed experimentally. The experimental tests were implemented in Baghdad during the January and February 2017. Five values of airflow rates range between 0.01 – 0.1 m3/s were used through the test with a constant airflow rate during the test day. The variation of the following parameters air temperature difference, useful energy, absorber plate temperature, and collector efficiency was recorded every 15 minutes. The experimental data reports that the increases the number of absorber plate perforations with a small diameter is more efficient rather than increasing the hole diameter of the absorber plate with decreasing the perforation numbers. Maximum air temperature difference throughout the solar collector with 3, 6 mm perforations and without perforations are 17, 15, and 12 oC, respectively. Also, it can be concluded that the energy gained from the solar collector with 3 mm perforation absorber plate is 28.2 % more than the energy gained from solar collector without holes per day for 0.1 m3/s airflow rate. The maximum values of the thermal performance curves are 0.67, 0.64, and 0.56 for the solar collector with 3, 6 mm, and without perforations, respectively.

  15. Study on `Tannix` an absorbent for heavy metals including uranium

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Yasuo [Mitsubishi Nuclear Fuel Co. Ltd., Tokyo (Japan)

    1997-09-01

    To treat radioactive wastes including uranium and transuranic elements such as plutonium, americium etc., development of an absorbent which can be used to absorb and isolate these elements without producing secondary wastes after treatment was attempted. And an absorbent has been successfully developed by polymerizing tannin, a natural product. It is known that tannin binds heavy metals including uranium resulting to produce their precipitates. There are some reports suggesting its absorption ability for uranium. However, tannin has not been used to isolate a heavy metal from a solution because it is soluble in water. Here, insolubilization of tannin was attempted and a manufacturing method for a gelatinized insoluble tannin named as ``Tannix`` was established. Wattle tannin extracted from Mimosa pudica produced in Africa was dissolved in an alkaline solution and gelatinized by heating after the addition of formalin. Thus obtained insoluble tannin was used after crushing and sieving. This product, ``Tannix`` was able to absorb more than 99% of uranium in the waste. And the absorbed Tannin could be degraded by incineration even at a low temperature, leaving only uranium, but not producing any secondary product. (M.N.)

  16. Vibration Attenuation of Plate Using Multiple Vibration Absorbers

    Directory of Open Access Journals (Sweden)

    Zaman Izzuddin

    2014-07-01

    Full Text Available Vibrations are undesired phenomenon and it can cause harm, distress and unsettling influence to the systems or structures, for example, aircraft, automobile, machinery and building. One of the approach to limit this vibration by introducing passive vibration absorber attached to the structure. In this paper, the adequacy of utilizing passive vibration absorbers are investigated. The vibration absorber system is designed to minimize the vibration of a thin plate fixed along edges. The plate’s vibration characteristics, such as, natural frequency and mode shape are determined using three techniques: theoretical equations, finite element (FE analysis and experiment. The results demonstrate that the first four natural frequencies of fixed-fixed ends plate are 48, 121, 193 and 242 Hz, and these results are corroborated well with theoretical, FE simulation and experiment. The experiment work is further carried out with attached single and multiple vibration absorbers onto plate by tuning the absorber’s frequency to match with the excitation frequency. The outcomes depict that multiple vibration absorbers are more viable in lessening the global structural vibration.

  17. A Proposal for a New HOM Absorber in a Straight Section of the PEP-II Low Energy Ring

    CERN Document Server

    Weathersby, Stephen; Kurita, Nadine; Novokhatski, Alexander; Seeman, John

    2005-01-01

    Attainment of high luminosity in storage ring colliders necessitates increasing stored currents and reducing bunch lengths. Consequently, intense beam fields will scatter more power into higher order modes from beam line sources such as collimators, masks and tapers. This power penetrates into sensitive components such as a bellows, causing undesirable heating and limits machine performance. To overcome this limitation we propose incorporating ceramic absorbers in the vicinity of the bellows to damp beam induced modes while preserving a matched impedance to the beam. This is accomplished with an absorber configuration which damps TE dipole and quadrupole traveling waves while preserving TM monopole propagation. A scattering parameter analysis is presented utilizing properties of commercial grade ceramics and indicates a feasible solution.

  18. Influence of an absorbers GEMPEHD thermal properties on the propagation of heat in a solar sensor

    Directory of Open Access Journals (Sweden)

    Nassim Baba Ahmed

    2018-01-01

    Full Text Available This paper presents an experimental study to measure some physic-chemical properties of a high-density polyethylene geomembane (GEMPEHD in a temperature range from 300 K to 400 K. The results will yield a dependency between temperature and its properties in order to study an energy and process the thermal aging GEMPEHD on the solar collector. In the energy study, we solve the nonlinear equation of unsteady heat with as main non linearity influence of different properties GEMPEHD on the solar collector and one notes that the GEMPEHD presented a maximum exchange Thermal characterized by high absorption and low reflection. Thus, increasing the power absorbed by the GEMPEHD increases its temperature and the useful power received by the air and then the air temperature. Overall losses increase with the increase of the temperature difference between the GEMPEHD and windows and this increases the efficiency of the solar collector and minimize the entropy of the system. Then the study of thermal aging is dedicated to the interpretation of various analyses on GEMPEHD before and after its use in the solar collector. The thermal aging GEMPEHD in the air is a physical loss and chemical consumption immediately followed by a brutal oxidation of the polymer. The losses would be governed primarily by the chemical consumption of antioxidants. After various tests, we conclude that the value of using the GEMPEHD as absorber in the solar collector is doubly beneficial. First, given its very attractive cost compared to other as efficient absorbers (such as metals gives good thermal performance of the solar collector even reaching 72%. While the life of the GEMPEHD is rather long (several years.

  19. Earning Management dan Expected Future Earning di Bursa Efek Indonesia

    Directory of Open Access Journals (Sweden)

    Taofiq Rachmat

    2017-09-01

    Full Text Available The purpose of this study was to applicated M-score to identify earning management in Indonesian corporation. This study also aims to analyst future earning condition from kind of group or sector of corporation which is indicated doing earning management. This study took a sample of 42 corporation using criteria about corporation which is had negatif information. The results of multiple linear regression analysis show that there is evidence that companies with an Earning Management detected earn lower future earnings (a study in Indonesian Stock Exchange Market, the ability of forecast changes in future earnings stems from its ability of predictive power of M-Score (Earning Management Detection Model. There is also, evidence that group companies which had “high attention” from Regulator earn lower expected future earnings. Based on the results of this study, the stake holder are advised to consider M-score to make judgement about financial reports.Keywords: earning management, expected future earning, indonesian stock exchange market, m-score, cross- sectional time-series dataAbstrak: Tujuan dari penelitian ini adalah untuk mengkaji aplikasi M-Score untuk mengidentifikasi earning management pada korporasi di Indonesia. Penelitian ini juga bertujuan mengkaji kondisi expected future earning dari kelompok korporasi yang di informasikan terindikasi melakukan earning management. Penelitian ini mengambil sampel dari 42 korporasi dengan menggunakan kriteria korporasi yang memiliki informasi negatif. Hasil analisis regresi linier berganda menunjukkan terdapat bukti apabila korporasi yang terdeteksi earning management akan mendapatkan expected future earning yang rendah. Kemampuan memprediksi perubahan pada expected future earning didapat dari kemampuan prediksi yang kuat dari M-score (Model untuk mendeteksi adanya earning management. Penelitian menunjukkan bahwa ditemukan konglomerasi usaha yang mendapat pengawasan dari regulator mendapatkan

  20. Comparison of ESD and major organ absorbed doses of 5 year old standard guidekines and clinical exposure conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kang, A Ram; Ahn, Sung Min [Dept. of Radiological Science, The Graduate School, Gachon University, Incheon (Korea, Republic of); Lee, In Ja [Dept. of Radiologic technology, Dongnam health University, Suwon (Korea, Republic of)

    2017-09-15

    Pediatrics are more sensibility to radiation than adults and because they are organs that are not completely grown, they have a life expectancy that can be adversely affected by exposure. Therefore, the management of exposure dose is more important than the case of adult. The purpose of this study was to determine the suitability of the 10 year old phantom for the 5 year old pediatric's recommendation and the incident surface dose, and to measure the organ absorbed dose. This study is compared the organ absorbed dose and the entrance surface dose in the clinical conditions at 5 and 10 years old pediatric. Clinical 5 year old condition was slightly higher than recommendation condition and 10 year old condition was very high. In addition, recommendation condition ESD was found to be 43% higher than the ESD of the 5 year old group and the ESD of the 10 year old group was 126% higher than that of the 5 year old group. The recommended ESD at 5 years old and the ESD according to clinical imaging conditions were 31.6%. There was no significant difference between the 5 year old recommended exposure conditions and the organ absorbed dose due to clinical exposure conditions, but there was a large difference between the Chest and Pelvic. However, it was found that there was a remarkable difference when comparing the organ absorbed dose by 10 year clinical exposure conditions. Therefore, more detailed standard exposure dose for the recommended dose of pediatric should be studied.

  1. Expectations, Bond Yields and Monetary Policy

    DEFF Research Database (Denmark)

    Chun, Albert Lee

    2011-01-01

    expectations about inflation, output growth, and the anticipated path of monetary policy actions contain important information for explaining movements in bond yields. Estimates from a forward-looking monetary policy rule suggest that the central bank exhibits a preemptive response to inflationary expectations...... while accommodating output growth and monetary policy expectations. Forecasted GDP growth plays a significant role in explaining time variation in the market prices of risk. The sensitivity of long yields is linked to the persistence of expected inflation under the risk-neutral measure. Models...

  2. Investigation of ZnO nanrod solar cells with layer-by-layer deposited CdTe quantum dot absorbers

    OpenAIRE

    Briscoe, Joe

    2011-01-01

    Innovation in solar cell design is required to reduce cost and compete with traditional power generation. Current innovative solar technologies include nanostructured dye-sensitised solar cells and polymer solar cells, which both contain organic materials with limited lifetime. This project aims to combine the advantages of ZnO nanorods and quantum dot (QD) absorbers in an all-inorganic solar cell, using the layer-by-layer (LbL) process to increase light absorption in the cell....

  3. Effect of p-layer properties on nanocrystalline absorber layer and thin film silicon solar cells

    International Nuclear Information System (INIS)

    Chowdhury, Amartya; Adhikary, Koel; Mukhopadhyay, Sumita; Ray, Swati

    2008-01-01

    The influence of the p-layer on the crystallinity of the absorber layer and nanocrystalline silicon thin film solar cells has been studied. Boron doped Si : H p-layers of different crystallinities have been prepared under different power pressure conditions using the plasma enhanced chemical vapour deposition method. The crystalline volume fraction of p-layers increases with the increase in deposition power. Optical absorption of the p-layer reduces as the crystalline volume fraction increases. Structural studies at the p/i interface have been done by Raman scattering studies. The crystalline volume fraction of the i-layer increases as that of the p-layer increases, the effect being more prominent near the p/i interface. Grain sizes of the absorber layer decrease from 9.2 to 7.2 nm and the density of crystallites increases as the crystalline volume fraction of the p-layer increases and its grain size decreases. With increasing crystalline volume fraction of the p-layer solar cell efficiency increases

  4. Review of Mid- to High-Temperature Solar Selective Absorber Materials

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, C. E.

    2002-07-01

    This report describes the concentrating solar power (CSP) systems using solar absorbers to convert concentrated sunlight to thermal electric power. It is possible to achieve solar absorber surfaces for efficient photothermal conversion having high solar absorptance (a) for solar radiation and a low thermal emittance (e) at the operational temperature. A low reflectance (?'' 0) at wavelengths (?) 3 mm and a high reflectance (?'' 1) at l 3 mm characterize spectrally selective surfaces. The operational temperature ranges of these materials for solar applications can be categorized as low temperature (T< 100 C), mid-temperature (100 C< T< 400 C), and high-temperature (T> 400 C). High- and mid-temperature applications are needed for CSP applications. For CSP applications, the ideal spectrally selective surface would be low-cost and easy to manufacture, chemically and thermally stable in air at elevated operating temperatures (T= 500 C), and have a solar absorptance= 0.98 and a thermal emittance= 0.05 at 500 C.

  5. Compositionally Graded Absorber for Efficient and Stable Near-Infrared-Transparent Perovskite Solar Cells.

    Science.gov (United States)

    Fu, Fan; Pisoni, Stefano; Weiss, Thomas P; Feurer, Thomas; Wäckerlin, Aneliia; Fuchs, Peter; Nishiwaki, Shiro; Zortea, Lukas; Tiwari, Ayodhya N; Buecheler, Stephan

    2018-03-01

    Compositional grading has been widely exploited in highly efficient Cu(In,Ga)Se 2 , CdTe, GaAs, quantum dot solar cells, and this strategy has the potential to improve the performance of emerging perovskite solar cells. However, realizing and maintaining compositionally graded perovskite absorber from solution processing is challenging. Moreover, the operational stability of graded perovskite solar cells under long-term heat/light soaking has not been demonstrated. In this study, a facile partial ion-exchange approach is reported to achieve compositionally graded perovskite absorber layers. Incorporating compositional grading improves charge collection and suppresses interface recombination, enabling to fabricate near-infrared-transparent perovskite solar cells with power conversion efficiency of 16.8% in substrate configuration, and demonstrate 22.7% tandem efficiency with 3.3% absolute gain when mechanically stacked on a Cu(In,Ga)Se 2 bottom cell. Non-encapsulated graded perovskite device retains over 93% of its initial efficiency after 1000 h operation at maximum power point at 60 °C under equivalent 1 sun illumination. The results open an avenue in exploring partial ion-exchange to design graded perovskite solar cells with improved efficiency and stability.

  6. Development of Improved Burnable Poisons for Commercial Nuclear Power Reactors

    Energy Technology Data Exchange (ETDEWEB)

    M. L. Grossbeck J-P.A. Renier Tim Bigelow

    2003-09-30

    Burnable poisons are used in nuclear reactors to produce a more level distribution of power in the reactor core and to reduce to necessity for a large control system. An ideal burnable poison would burn at the same rate as the fuel. In this study, separation of neutron-absorbing isotopes was investigated in order to eliminate isotopes that remain as absorbers at the end of fuel life, thus reducing useful fuel life. The isotopes Gd-157, Dy-164, and Er-167 were found to have desirable properties. These isotopes were separated from naturally occurring elements by means of plasma separation to evaluate feasibility and cost. It was found that pure Gd-157 could save approximately $6 million at the end of four years. However, the cost of separation, using the existing facility, made separation cost- ineffective. Using a magnet with three times the field strength is expected to reduce the cost by a factor of ten, making isotopically separated burnable poisons a favorable method of increasing fuel life in commercial reactors, in particular Generation-IV reactors. The project also investigated various burnable poison configurations, and studied incorporation of metallic burnable poisons into fuel cladding.

  7. Development of Improved Burnable Poisons for Commercial Nuclear Power Reactors

    International Nuclear Information System (INIS)

    Grossbeck, M. L.; Renier, J-P.A.; Bigelow, Tim

    2003-01-01

    Burnable poisons are used in nuclear reactors to produce a more level distribution of power in the reactor core and to reduce to necessity for a large control system. An ideal burnable poison would burn at the same rate as the fuel. In this study, separation of neutron-absorbing isotopes was investigated in order to eliminate isotopes that remain as absorbers at the end of fuel life, thus reducing useful fuel life. The isotopes Gd-157, Dy-164, and Er-167 were found to have desirable properties. These isotopes were separated from naturally occurring elements by means of plasma separation to evaluate feasibility and cost. It was found that pure Gd-157 could save approximately $6 million at the end of four years. However, the cost of separation, using the existing facility, made separation cost- ineffective. Using a magnet with three times the field strength is expected to reduce the cost by a factor of ten, making isotopically separated burnable poisons a favorable method of increasing fuel life in commercial reactors, in particular Generation-IV reactors. The project also investigated various burnable poison configurations, and studied incorporation of metallic burnable poisons into fuel cladding

  8. High-temperature absorbed dose measurements in the megagray range

    International Nuclear Information System (INIS)

    Balian, P.; Ardonceau, J.; Zuppiroli, L.

    1988-01-01

    Organic conductors of the tetraselenotetracene family have been tested as ''high-temperature'' absorbed dose dosimeters. They were heated up to 120 0 C and irradiated at this temperature with 1-MeV electrons in order to simulate, in a short time, a much longer γ-ray irradiation. The electric resistance increase of the crystal can be considered a good measurement of the absorbed dose in the range 10 6 Gy to a few 10 8 Gy and presumably one order of magnitude more. This dosimeter also permits on-line (in-situ) measurements of the absorbed dose without removing the sensor from the irradiation site. The respective advantages of organic and inorganic dosimeters at these temperature and dose ranges are also discussed. In this connection, we outline new, but negative, results concerning the possible use of silica as a high-temperature, high-dose dosimeter. (author)

  9. Absorber rod bundle actuator in a pressurized water nuclear reactor

    International Nuclear Information System (INIS)

    Martin, J.; Peletan, R.

    1984-01-01

    The invention concerns an absorber rod bundle actuator in a pressurized water reactor with spectral shift control. The device comprises two coaxial control bars. The inner bar is integral with the absorber rod bundle; it has an enlarged zone which acts as a proton under pressure difference across an annular seal which can be radially expanded, the pressure difference allowing to the absorber rod bundles actuating on the piston. When a pressure difference is applied, the seal expands radially by a sufficient amount to make sealing contact with the zone of larger diameter in the outer bar. The invention applies more particularly to reactors with spectral shift control using bundles of fertile rods [fr

  10. Preview control of vehicle suspension system featuring MR shock absorber

    International Nuclear Information System (INIS)

    Seong, M S; Choi, S B; Cho, M W; Lee, H G

    2009-01-01

    This paper presents control performance evaluation of optimal preview control algorithm for vehicle suspension featuring MR shock absorber. The optimal preview control algorithm has several advantages such as high control performance over that which is best for a non-preview system. In order to achieve this goal, a commercial MR shock absorber, Delphi MganerideTM, which is applicable to high class passenger vehicle, is adopted and its field-dependent damping force and dynamic responses are experimentally evaluated. Then the governing equation of motion for the full-vehicle model is established and integrated with the MR shock absorber. Subsequently, optimal controller with preview control algorithm is formulated and implemented for vibration suppression of the car body. Control performance of the preview controller is evaluated for the full-vehicle model under random road condition. In addition, the control performances depending on preview distances are evaluated.

  11. Time improvement of photoelectric effect calculation for absorbed dose estimation

    International Nuclear Information System (INIS)

    Massa, J M; Wainschenker, R S; Doorn, J H; Caselli, E E

    2007-01-01

    Ionizing radiation therapy is a very useful tool in cancer treatment. It is very important to determine absorbed dose in human tissue to accomplish an effective treatment. A mathematical model based on affected areas is the most suitable tool to estimate the absorbed dose. Lately, Monte Carlo based techniques have become the most reliable, but they are time expensive. Absorbed dose calculating programs using different strategies have to choose between estimation quality and calculating time. This paper describes an optimized method for the photoelectron polar angle calculation in photoelectric effect, which is significant to estimate deposited energy in human tissue. In the case studies, time cost reduction nearly reached 86%, meaning that the time needed to do the calculation is approximately 1/7 th of the non optimized approach. This has been done keeping precision invariant

  12. Absorber for microwave investigation in the open space

    Science.gov (United States)

    Kubacki, Roman; Smólski, Bogusław; Głuszewski, Wojciech; Przesmycki, Rafał; Rudyk, Karol

    2017-04-01

    In some circumstances there is a need to realize the Electromagnetic Compatibility (EMC) investigation not in the specialized anechoic chamber but in the open space. Typical absorbers used in anechoic chamber to reduce the reflected rays from walls and floor, such as ferrite plates and graphite cones, are not suitable in the open space. In the work the investigation of the flexible absorbing material intended to the liquidation of the radiation reflected from the ground has been presented. As an absorbing material the metallic-glass with graphite was elaborated. This material was additionally exposed to the ionizing radiation in the dose of 100 kGy in the radioactive gamma source. The permittivity, permeability as well as the shielding properties have been analyzed.

  13. Constraining MHD Disk-Winds with X-ray Absorbers

    Science.gov (United States)

    Fukumura, Keigo; Tombesi, F.; Shrader, C. R.; Kazanas, D.; Contopoulos, J.; Behar, E.

    2014-01-01

    From the state-of-the-art spectroscopic observations of active galactic nuclei (AGNs) the robust features of absorption lines (e.g. most notably by H/He-like ions), called warm absorbers (WAs), have been often detected in soft X-rays (UFOs) whose physical condition is much more extreme compared with the WAs. Motivated by these recent X-ray data we show that the magnetically- driven accretion-disk wind model is a plausible scenario to explain the characteristic property of these X-ray absorbers. As a preliminary case study we demonstrate that the wind model parameters (e.g. viewing angle and wind density) can be constrained by data from PG 1211+143 at a statistically significant level with chi-squared spectral analysis. Our wind models can thus be implemented into the standard analysis package, XSPEC, as a table spectrum model for general analysis of X-ray absorbers.

  14. Graphene induced tunable and polarization-insensitive broadband metamaterial absorber

    Science.gov (United States)

    Zhang, Yuping; Li, Yue; Cao, Yanyan; Liu, Yuanzhong; Zhang, Huiyun

    2017-01-01

    We design a tunable and broadband metamaterial absorber in the mid-infrared region based on graphene. The unit cell of the proposed metamaterial absorber consists of circular gold patches, which coupled with a graphene layer, and are separated by a dielectric spacer from the gold film on the bottom. The absorption bandwidth is effectively extended by patterning multi-circular gold patches of different dimension elements with appropriate geometrical parameters in a co-plane. The metamaterial absorber achieves its frequency tunable characteristics via changing the applied voltage or chemical doping to manipulate graphene's Fermi energy. We analyzed the surface current distributions and the distributions of the z-component electric field for understanding the absorption mechanism. Moreover, the design principle here could be regarded as a template to extend bandwidth by introducing more circular patches into each unit cell. Our design has potential applications in various fields of stealth technology, photovoltaic devices, sensors, and broadband communication.

  15. The dynamics analysis of a ferrofluid shock absorber

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Jie; Chang, Jianjun [School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China); Li, Decai, E-mail: dcli@bjtu.edu.cn [School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China); Yang, Xiaolong [School of Mechanical Engineering, Guangxi University of Science and Technology, Liuzhou, Guangxi 545006 (China)

    2016-03-15

    The paper presents a shock absorber using three magnets as the inertial mass. Movement of the inertial mass inside a cylindrical body filled with ferrofluid will lead to a viscous dissipation of the oscillating system energy. The influence of a dumbbell-like ferrofluid structure on the energy dissipation is considered and the magnetic restoring force is investigated by experiment and theoretical calculation. A theoretical model of the hydrodynamics and energy dissipation processes is developed, which includes the geometrical characteristics of the body, the fluid viscosity, and the external magnetic field. The theory predicts the experimental results well under some condition. The shock absorber can be used in spacecraft technology. - Highlights: • We study a ferrofluid shock absorber. • The mechanical model of the flow of the ferrofluid has been built. • The theoretical model of the energy dissipation processes is developed. • The magnetic restoring force between the body and the magnets has been measured.

  16. Terahertz metamaterials perfect absorbers for sensing and imaging

    Science.gov (United States)

    Wilbert, David S.; Hokmabadi, Mohammad P.; Martinez, Joshua; Kung, Patrick; Kim, Seongsin M.

    2013-02-01

    Devices operating at THz frequencies have been continuously expanded in many areas of application and major research field, which requires materials with suitable electromagnetic responses at THz frequency ranges. Unlike most naturally occurring materials, novel THz metamaterials have proven to be well suited for use in various devices due to narrow and tunable operating ranges. In this work, we present the results of two THz metamaterial absorber structures aiming two important device aspects; polarization sensitivity and broad band absorption. The absorbers were simulated by finite element method and fabricated through the combination of standard lift-off photolithography and electron beam metal deposition. The fabricated devices were characterized by reflection mode THz time domain spectroscopy. The narrow band absorber structures exhibit up to 95% absorption with a bandwidth of 0.1 THz to 0.15 THz.

  17. An international intercomparison of absorbed dose measurements for radiation therapy

    International Nuclear Information System (INIS)

    Taiman Kadni; Noriah Mod Ali

    2002-01-01

    Dose intercomparison on an international basis has become an important component of quality assurance measurement i.e. to check the performance of absorbed dose measurements in radiation therapy. The absorbed dose to water measurements for radiation therapy at the SSDL, MINT have been regularly compared through international intercomparison programmes organised by the IAEA Dosimetry Laboratory, Seibersdorf, Austria such as IAEA/WHO TLD postal dose quality audits and the Intercomparison of therapy level ionisation chamber calibration factors in terms of air kerma and absorbed dose to water calibration factors. The results of these intercomparison in terms of percentage deviations for Cobalt 60 gamma radiation and megavoltage x-ray from medical linear accelerators participated by the SSDL-MINT during the year 1985-2001 are within the acceptance limit. (Author)

  18. Filtration: Novel Absorber Evaluation Club aims at standardized testing

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    In the past few years a number of novel absorber materials, both organic and inorganic, have appeared on the market - some claiming to achieve very large decontamination factors for metal ions, including those having radioactive isotopes. Several of these materials have been tested by individual companies in the nuclear industry and some have shown promise as decontaminants for radioactive waste streams. Unfortunately, the results obtained for the treatment of a particular waste stream cannot be applied directly to the many and diverse waste streams generated throughout the nuclear industry. A unified and standardized testing programme making use of available expertise is necessary to provide a fair and meaningful comparison. In November 1988, representatives of the United Kingdom nuclear industry agreed to form the Novel Absorber Evaluation Club to assess absorber materials and to undertake the necessary work to identify the extent and rate of adsorption of radionuclides by such materials from a set of typical reference waste streams. (author)

  19. Enhancement of acoustical performance of hollow tube sound absorber

    International Nuclear Information System (INIS)

    Putra, Azma; Khair, Fazlin Abd; Nor, Mohd Jailani Mohd

    2016-01-01

    This paper presents acoustical performance of hollow structures utilizing the recycled lollipop sticks as acoustic absorbers. The hollow cross section of the structures is arranged facing the sound incidence. The effects of different length of the sticks and air gap on the acoustical performance are studied. The absorption coefficient was measured using impedance tube method. Here it is found that improvement on the sound absorption performance is achieved by introducing natural kapok fiber inserted into the void between the hollow structures. Results reveal that by inserting the kapok fibers, both the absorption bandwidth and the absorption coefficient increase. For test sample backed by a rigid surface, best performance of sound absorption is obtained for fibers inserted at the front and back sides of the absorber. And for the case of test sample with air gap, this is achieved for fibers introduced only at the back side of the absorber.

  20. The behaviour of control rod absorber under irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bourgoin, J. [Electricite de France, Avoine (France). Groupe des Laboratoires; Couvreur, F.; Gosset, D. [CEA-Saclay, Service d' Etude des Materiaux Irradies, 91191, Gif-sur-Yvette (France); Defoort, F.; Monchanin, M. [Framatome Nuclear Fuel, 10 rue J. Recamier 69456, Lyon (France); Thibault, X. [Electricite de France, SEPTEN, 12-14 avenue Dutrievoz, 69628, Villeurbanne (France)

    1999-12-01

    Increase of rod diameters and cracking of PWR control rod claddings may occur in operation. In order to understand the contribution of the absorber properties to this damage, EDF and FRAMATOME launched a programme of examinations concerning the silver-indium-cadmium alloy constituting the absorber bars. Density measurements and microstructural investigations such as micrography, microanalysis were carried out in the EDF Hot Laboratory, X-ray diffraction was performed by CEA. The results show that transmutations induce chemical modifications inside the FCC alloy and, further, formation of an HCP phase similar to the {zeta} phase of the silver alloys. The chemical and crystallographic changes account for the major part of the absorber swelling. (orig.)