WorldWideScience

Sample records for technologies including thermoacoustics

  1. Design and optimization of thermoacoustic devices

    International Nuclear Information System (INIS)

    Babaei, Hadi; Siddiqui, Kamran

    2008-01-01

    Thermoacoustics deals with the conversion of heat energy into sound energy and vice versa. It is a new and emerging technology which has a strong potential towards the development of sustainable and renewable energy systems by utilizing waste heat or solar energy. Although simple to fabricate, the designing of thermoacoustic devices is very challenging. In the present study, a comprehensive design and optimization algorithm is developed for designing thermoacoustic devices. The unique feature of the present algorithm is its ability to design thermoacoustically-driven thermoacoustic refrigerators that can serve as sustainable refrigeration systems. In addition, new features based on the energy balance are also included to design individual thermoacoustic engines and acoustically-driven thermoacoustic refrigerators. As a case study, a thermoacoustically-driven thermoacoustic refrigerator has been designed and optimized based on the developed algorithm. The results from the algorithm are in good agreement with that obtained from the computer code DeltaE

  2. Review of investigations in eco-friendly thermoacoustic refrigeration system

    Directory of Open Access Journals (Sweden)

    Raut Ashish S.

    2017-01-01

    Full Text Available To reduce greenhouse gas emissions, internationally research and development is intended to improve the performance of conventional refrigeration system also growth of new-fangled refrigeration technology of potentially much lesser ecological impact. This paper gives brief review of research and development in thermoacoustic refrigeration also the existing situation of thermoacoustic refrigeration system. Thermoacoustic refrigerator is a novel sort of energy conversion equipment which converts acoustic power into heat energy by thermoacoustic effect. Thermoacoustic refrigeration is an emergent refrigeration technology in which there are no moving elements or any environmentally injurious refrigerants during its working. The concept of thermoacoustic refrigeration system is explained, the growth of thermoacoustic refrigeration, various investigations into thermoacoustic refrigeration system, various optimization techniques to improve coefficient of performance, different stacks and resonator tube designs to improve heat transfer rate, various gases, and other parameters like sound generation have been reviewed.

  3. Heat transfer in a thermoacoustic process

    International Nuclear Information System (INIS)

    Beke, Tamas

    2012-01-01

    Thermoacoustic instability is defined as the excitation of acoustic modes in chambers with heat sources due to the coupling between acoustic perturbations and unsteady heat addition. The major objective of this paper is to achieve accurate theoretical results in a thermoacoustic heat transfer process. We carry out a detailed heat transfer analysis aimed at determining the stability–instability border of the thermoacoustic system. In this paper, we present a project type of physical examination and modelling task. We employed an electrically heated Rijke tube in our thermoacoustic project work. The aim of our project is to help our students enlarge their knowledge about thermodynamics, mainly about thermoacoustics, and develop their applied information technology and mathematical skills. (paper)

  4. Modelling of thermoacoustic phenomena in an electrically heated Rijke tube

    International Nuclear Information System (INIS)

    Beke, Tamas

    2010-01-01

    Thermoacoustic instability plays an important role in various technical applications, for instance in jet or rocket motors, thermoacoustic engines, pulse combustors and industrial burners. The main objective of this paper is to present the theory of thermoacoustic oscillations, and for this purpose a Rijke-type thermal device was built. The Rijke tube is a simple device open at both ends with a mean airflow and a concentrated heat source (a heated wire grid). It serves as a convenient prototypical example to understand thermoacoustic effects since it is a simplified thermoacoustic resonator; once excited, under certain conditions, it is capable of creating a sustained sound when thermal energy is added. In this paper we present a project that includes physical measuring, examination and modelling. We have employed electrically heated Rijke tubes in our thermoacoustic school project work, and present a numerical algorithm to predict the transition to instability; in this model the effects of the main system parameters are demonstrated. The aim of our project is to help our students enhance their knowledge about thermoacoustics and develop their applied information technology skills.

  5. Modelling of thermoacoustic phenomena in an electrically heated Rijke tube

    Energy Technology Data Exchange (ETDEWEB)

    Beke, Tamas, E-mail: tamasbe@gmail.co [Our Lady Catholic Institute, Kalocsa (Hungary)

    2010-11-15

    Thermoacoustic instability plays an important role in various technical applications, for instance in jet or rocket motors, thermoacoustic engines, pulse combustors and industrial burners. The main objective of this paper is to present the theory of thermoacoustic oscillations, and for this purpose a Rijke-type thermal device was built. The Rijke tube is a simple device open at both ends with a mean airflow and a concentrated heat source (a heated wire grid). It serves as a convenient prototypical example to understand thermoacoustic effects since it is a simplified thermoacoustic resonator; once excited, under certain conditions, it is capable of creating a sustained sound when thermal energy is added. In this paper we present a project that includes physical measuring, examination and modelling. We have employed electrically heated Rijke tubes in our thermoacoustic school project work, and present a numerical algorithm to predict the transition to instability; in this model the effects of the main system parameters are demonstrated. The aim of our project is to help our students enhance their knowledge about thermoacoustics and develop their applied information technology skills.

  6. A high performance thermoacoustic Stirling-engine

    Energy Technology Data Exchange (ETDEWEB)

    Tijani, M.E.H.; Spoelstra, S. [Energy research Centre of the Netherlands (ECN), PO Box 1, 1755 ZG Petten (Netherlands)

    2011-11-10

    In thermoacoustic systems heat is converted into acoustic energy and vice versa. These systems use inert gases as working medium and have no moving parts which makes the thermoacoustic technology a serious alternative to produce mechanical or electrical power, cooling power, and heating in a sustainable and environmentally friendly way. A thermoacoustic Stirling heat engine is designed and built which achieves a record performance of 49% of the Carnot efficiency. The design and performance of the engine is presented. The engine has no moving parts and is made up of few simple components.

  7. The role of thermoacoustics in the world of commercial cooling

    Science.gov (United States)

    Corey, John A.

    2005-09-01

    The science of thermoacoustics has been with us for nearly 30 years, but as yet few applications have made their way to the marketplace. Acoustic Stirling cryocoolers (also called pulse-tube Stirling or high-frequency pulse-tube coolers) have been the most successful commercial thermoacoustic devices, because they address a region of the cooling market in terms of temperature and cooling power that is not well served by existing technology. This talk will explore how thermoacoustics might fare in attempting to compete with existing technologies in refrigeration and air conditioning, what niche markets make the most sense as entry points, and how thermoacoustics compares to conventional (kinematic or free-piston) Stirling machines. In particular, why there are relatively few commercial Stirling devices in the marketplace (although Stirling cycle machines have been around for over 150 years) will be discussed, and what lessons learned with Stirlings are applicable to thermoacoustics.

  8. High temperature thermoacoustic heat pump

    Energy Technology Data Exchange (ETDEWEB)

    Tijani, H.; Spoelstra, S. [Energy research Centre of the Netherlands, 1755 ZG Petten (Netherlands)

    2012-06-15

    Thermoacoustic technology can provide new types of heat pumps that can be deployed in different applications. A thermoacoustic heat pumps can for example be applied in dwellings to generate cooling or heating. Typically, space and water heating makes up about 60% of domestics and offices energy consumption. The application of heat pumps can contribute to achieve energy savings and environmental benefits by reducing CO2 and NOx emissions. This paper presents the study of a laboratory scale thermoacoustic-Stirling heat pump operating between 10C and 80C which can be applied in domestics and offices. The heat pump is driven by a thermoacoustic-Stirling engine. The experimental results show that the heat pump pumps 250 W of heat at 60C at a drive ratio of 3.6% and 200 W at 80C at a drive ratio of 3.5 %. The performance for both cases is about 40% of the Carnot performance. The design, construction, and performance measurements of the heat pump will be presented and discussed.

  9. High Temperature Thermoacoustic Heat Pump

    Energy Technology Data Exchange (ETDEWEB)

    Tijani, H.; Spoelstra, S. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2012-07-15

    Thermoacoustic technology can provide new types of heat pumps that can be deployed in different applications. Thermoacoustic heat pumps can for example be applied in dwellings to generate cooling or heating. Typically, space and water heating makes up about 60% of domestic and office energy consumption. The application of heat pumps can contribute to achieve energy savings and environmental benefits by reducing CO2 and NOx emissions. This paper presents the study of a laboratory scale thermoacoustic-Stirling heat pump operating between 10C and 80C which can be applied in domestics and offices. The heat pump is driven by a thermoacoustic-Stirling engine. The experimental results show that the heat pump pumps 250 W of heat at 60C at a drive ratio of 3.6 % and 200 W at 80C at a drive ratio of 3.5 %. The performance for both cases is about 40% of the Carnot performance. The design, construction, and performance measurements of the heat pump will be presented and discussed.

  10. Development of a Thermoacoustic Stirling Engine Technology Demonstrator

    Science.gov (United States)

    Reissner, Alexander; Gerger, Joachim; Hummel, Stefan; Reißig, Jannis; Pawelke, Roland

    2014-08-01

    Waste heat is a primary source of energy loss in many aerospace and terrestrial applications. FOTEC, an Austrian Research Company located in Wiener Neustadt, is presently developing a micro power converter, promising high efficiencies even for small- scale applications. The converter is based on an innovative thermoacoustic stirling engine concept without any moving parts. Such a maintenance-free engine system would be particularly suitable for advanced space power systems (radioisotope, waste heat) or even within the scope of terrestrial energy harvesting. This paper will summarizes the status of our ongoing efforts on this micro power converter technology.

  11. Review on the conversion of thermoacoustic power into electricity.

    Science.gov (United States)

    Timmer, Michael A G; de Blok, Kees; van der Meer, Theo H

    2018-02-01

    Thermoacoustic engines convert heat energy into high amplitude acoustic waves and subsequently into electric power. This article provides a review of the four main methods to convert the (thermo)acoustic power into electricity. First, loudspeakers and linear alternators are discussed in a section on electromagnetic devices. This is followed by sections on piezoelectric transducers, magnetohydrodynamic generators, and bidirectional turbines. Each segment provides a literature review of the given technology for the field of thermoacoustics, focusing on possible configurations, operating characteristics, output performance, and analytical and numerical methods to study the devices. This information is used as an input to discuss the performance and feasibility of each method, and to identify challenges that should be overcome for a more successful implementation in thermoacoustic engines. The work is concluded by a comparison of the four technologies, concentrating on the possible areas of application, the conversion efficiency, maximum electrical power output and more generally the suggested focus for future work in the field.

  12. Energy transfer modelling of active thermoacoustic engines via Lagrangian thermoacoustic dynamics

    International Nuclear Information System (INIS)

    Hong, Boe-Shong; Chou, Chia-Yu

    2014-01-01

    Highlights: • Resonant control on thermoacoustic engines to amplify power rating. • Least-action principle of thermoacoustic dynamics to shape engine chamber. • Spatiotemporal transfer function into feedback systems. • Conservation law of thermoacoustic storage to figure out engine cycles. • Robin boundary condition to identify flow leakage. - Abstract: This paper develops energy-transfer modelling of active thermoacoustic engines resonantly controlled on boundary for amplification of power rating toward satisfaction of renewable industry. Therein the wave equation of thermoacoustic dynamics in resonators with non-uniform media and boundary actuations is derived and then turned into a least-action principle. With this least-action principle, we obtain the governing equation of longitudinal resonators with spatially variant cross-section areas to investigate how to shape the resonator for boosting piston stroke and power-transmission efficiency. It is followed by spatiotemporal transfer-function modelling that functionally represents the dynamics and interprets the boundary actuations into internal inputs. This helps formulate the overall dynamics into feedback-interconnection between the thermoacoustic dynamics in the resonator and the mechatronic dynamics of the alternative current generator, so that synthesis of feedback systems can be applied to design the entire engine. Transfer-function modelling following least-action principle leads to the conservation law of thermoacoustic storage, which figures out engine cycles, the most fundamental principle in designing active thermoacoustic engines. Based on such feedback realization, digital signal processing is programmed to numerically assess power ratings of active designs

  13. Thermoacoustic refrigeration

    Science.gov (United States)

    Garrett, Steven L.; Hofler, Thomas J.

    1991-12-01

    A new refrigerator which uses resonant high amplitude sound in inert gases to pump heat is described and demonstrated. The phasing of the thermoacoustic cycle is provided by thermal conduction. This 'natural' phasing allows the entire refrigerator to operate with only one moving part (the loudspeaker diaphragm). The thermoacoustic refrigerator has no sliding seals, requires no lubrication, uses only low-tolerance machine parts, and contains no expensive components. Because the compressor moving mass is typically small and the oscillation frequency is high, the small amount of vibration is very easily isolated. This low vibration and lack of sliding seals makes thermoacoustic refrigeration an excellent candidate for food refrigeration and commercial/residential air conditioning applications. The design, fabrication, and performance of the first practical, autonomous thermoacoustic refrigerator, which will be flown on the Space Shuttle (STS-42), are described, and designs for terrestrial applications are presented.

  14. Thermo-Acoustic Convertor for Space Power, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Sunpower will introduce thermoacoustic Stirling heat engine (TASHE) technology into its existing Stirling convertor technology to eliminate the moving mechanical...

  15. Physics of thermo-acoustic sound generation

    Science.gov (United States)

    Daschewski, M.; Boehm, R.; Prager, J.; Kreutzbruck, M.; Harrer, A.

    2013-09-01

    We present a generalized analytical model of thermo-acoustic sound generation based on the analysis of thermally induced energy density fluctuations and their propagation into the adjacent matter. The model provides exact analytical prediction of the sound pressure generated in fluids and solids; consequently, it can be applied to arbitrary thermal power sources such as thermophones, plasma firings, laser beams, and chemical reactions. Unlike existing approaches, our description also includes acoustic near-field effects and sound-field attenuation. Analytical results are compared with measurements of sound pressures generated by thermo-acoustic transducers in air for frequencies up to 1 MHz. The tested transducers consist of titanium and indium tin oxide coatings on quartz glass and polycarbonate substrates. The model reveals that thermo-acoustic efficiency increases linearly with the supplied thermal power and quadratically with thermal excitation frequency. Comparison of the efficiency of our thermo-acoustic transducers with those of piezoelectric-based airborne ultrasound transducers using impulse excitation showed comparable sound pressure values. The present results show that thermo-acoustic transducers can be applied as broadband, non-resonant, high-performance ultrasound sources.

  16. Being everything to anyone: Applicability of thermoacoustic technology in the commercial refrigeration market

    Science.gov (United States)

    Poese, Matthew E.; Smith, Robert W. M.; Garrett, Steven L.

    2005-09-01

    This talk will compare electrodynamically driven thermoacoustic refrigeration technology to some common implementations of low-lift vapor-compression technology. A rudimentary explanation of vapor-compression refrigeration will be presented along with some of the implementation problems faced by refrigeration engineers using compressor-based systems. These problems include oil management, compressor slugging, refrigerant leaks and the environmental impact of refrigerants. Recently, the method of evaluating this environmental impact has been codified to include the direct effects of the refrigerants on global warming as well as the so-called ``indirect'' warming impact of the carbon dioxide released during the generation (at the power plant) of the electrical power consumed by the refrigeration equipment. It is issues like these that generate commercial interest in an alternative refrigeration technology. However, the requirements of a candidate technology for adoption in a mature and risk-averse commercial refrigeration industry are as hard to divine as they are to meet. Also mentioned will be the state of other alternative refrigeration technologies like free-piston Stirling, thermoelectric and magnetocaloric as well as progress using vapor compression technology with alternative refrigerants like hydrocarbons and carbon dioxide.

  17. Micro-Scale Thermoacoustics

    Science.gov (United States)

    Offner, Avshalom; Ramon, Guy Z.

    2016-11-01

    Thermoacoustic phenomena - conversion of heat to acoustic oscillations - may be harnessed for construction of reliable, practically maintenance-free engines and heat pumps. Specifically, miniaturization of thermoacoustic devices holds great promise for cooling of micro-electronic components. However, as devices size is pushed down to micro-meter scale it is expected that non-negligible slip effects will exist at the solid-fluid interface. Accordingly, new theoretical models for thermoacoustic engines and heat pumps were derived, accounting for a slip boundary condition. These models are essential for the design process of micro-scale thermoacoustic devices that will operate under ultrasonic frequencies. Stability curves for engines - representing the onset of self-sustained oscillations - were calculated with both no-slip and slip boundary conditions, revealing improvement in the performance of engines with slip at the resonance frequency range applicable for micro-scale devices. Maximum achievable temperature differences curves for thermoacoustic heat pumps were calculated, revealing the negative effect of slip on the ability to pump heat up a temperature gradient. The authors acknowledge the support from the Nancy and Stephen Grand Technion Energy Program (GTEP).

  18. Thermoacoustic refrigerator for space applications

    Science.gov (United States)

    Garrett, Steven L.; Adeff, Jay A.; Hofler, Thomas J.

    1993-10-01

    A new spacecraft cryocooler which uses resonant high-amplitude sound waves in inert gases to pump heat is described. The phasing of the thermoacoustic cycle is provided by thermal conduction. This 'natural' phasing allows the entire refrigerator to operate with only one moving part (the loudspeaker diaphragm). A space-qualified thermoacoustic refrigerator was flown on the Space Shuttle Discovery (STS-42) in January, 1992. It was entirely autonomous, had no sliding seals, required no lubrication, used mostly low-tolerance machined parts, and contained no expensive components. Thermoacoustics is shown to be a competitive candidate for food refrigerator/freezers and commercial/residential air conditioners. The design and performance of the Space Thermo/Acoustic Refrigerator (STAR) is described.

  19. Sensitivity and Nonlinearity of Thermoacoustic Oscillations

    Science.gov (United States)

    Juniper, Matthew P.; Sujith, R. I.

    2018-01-01

    Nine decades of rocket engine and gas turbine development have shown that thermoacoustic oscillations are difficult to predict but can usually be eliminated with relatively small ad hoc design changes. These changes can, however, be ruinously expensive to devise. This review explains why linear and nonlinear thermoacoustic behavior is so sensitive to parameters such as operating point, fuel composition, and injector geometry. It shows how nonperiodic behavior arises in experiments and simulations and discusses how fluctuations in thermoacoustic systems with turbulent reacting flow, which are usually filtered or averaged out as noise, can reveal useful information. Finally, it proposes tools to exploit this sensitivity in the future: adjoint-based sensitivity analysis to optimize passive control designs and complex systems theory to warn of impending thermoacoustic oscillations and to identify the most sensitive elements of a thermoacoustic system.

  20. Transmission eigenvalues and thermoacoustic tomography

    International Nuclear Information System (INIS)

    Finch, David; Hickmann, Kyle S

    2013-01-01

    The spectrum of the interior transmission problem is related to the unique determination of the acoustic properties of a body in thermoacoustic imaging. Under a non-trapping hypothesis, we show that sparsity of the interior transmission spectrum implies a range separation condition for the thermoacoustic operator. In odd dimensions greater than or equal to 3, we prove that the interior transmission spectrum for a pair of radially symmetric non-trapping sound speeds is countable, and conclude that the ranges of the associated thermoacoustic maps have only trivial intersection. (paper)

  1. Numerical analysis on a four-stage looped thermoacoustic Stirling power generator for low temperature waste heat

    International Nuclear Information System (INIS)

    Wang, Kai; Qiu, Limin

    2017-01-01

    Highlights: • Four-stage looped thermoacoustic power generator for waste heat is studied. • Coupling position is found to have remarkable effects on performance. • Better efficiency is available when coupled near the cold ends of the cores. • The influence of the regenerator position on the efficiency is weak. • Matching between the acoustic impedances of engine and alternator is important. - Abstract: Recent developments in thermoacoustic technologies have demonstrated that multi-stage looped thermoacoustic Stirling engine would be a promising option for harvesting waste heat. Previous studies on multi-stage looped thermoacoustic systems were mainly focused on heat-driven refrigeration or heat pumping, while much fewer work were done on power generations, especially those for recovering low temperature heat. In this work, a four-stage looped thermoacoustic Stirling power generator for generating electricity from low temperature waste heat at 300 °C is systematically studied. A numerical model is built and then validated on an experimental four-stage looped thermoacoustic Stirling engine. On the basis of the validated model, the effects of the coupling position for the linear alternators and the regenerator position on the acoustic characteristics and performances of the power generation system are numerically investigated. The distributions of the acoustic fields along the loop, including the pressure amplitude, volume flow rate, phase angle, specific acoustic impedance and acoustic power, are presented and analysed for three representative coupling modes. Superior efficiency is achieved when the linear alternators are coupled near the cold ends of the thermoacoustic cores on the resonators, while more electric power is generated at the hot ends. The worst performance is expected when the linear alternators are connected at the middle of the resonators. The underling mechanisms are further explained detailedly by analysing the characteristics of the

  2. Experimental study of the influence of different resonators on thermoacoustic conversion performance of a thermoacoustic-Stirling heat engine.

    Science.gov (United States)

    Luo, E C; Ling, H; Dai, W; Yu, G Y

    2006-12-22

    In this paper, an experimental study of the effect of the resonator shape on the performance of a traveling-wave thermoacoustic engine is presented. Two different resonators were tested in the thermoacoustic-Stirling heat. One resonator is an iso-diameter one, and the other is a tapered one. To have a reasonable comparison reference, we keep the same traveling-wave loop, the same resonant frequency and the same operating pressure. The experiment showed that the resonator shape has significant influence on the global performance of the thermoacoustic-Stirling heat engine. The tapered resonator gives much better performance than the iso-diameter resonator. The tapered resonator system achieved a maximum pressure ratio of about 1.3, a maximum net acoustical power output of about 450 W and a highest thermoacoustic efficiency of about 25%.

  3. Thermoacoustic magnetohydrodynamic electrical generator

    International Nuclear Information System (INIS)

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1986-01-01

    A thermoacoustic magnetohydrodynamic electrical generator is described comprising a magnet having a magnetic field, an elongate hollow housing containing an electrically conductive liquid and a thermoacoustic structure positioned in the liquid, heat exchange means thermally connected to the thermoacoustic structure for inducing the liquid to oscillate at an acoustic resonant frequency within the housing. The housing is positioned in the magnetic field and oriented such that the direction of the magnetic field and the direction of oscillatory motion of the liquid are substantially orthogonal to one another, first and second electrical conductor means connected to the liquid on opposite sides of the housing along an axis which is substantially orthogonal to both the direction of the magnetic field and the direction of oscillatory motion of the liquid, an alternating current output signal is generated in the conductor means at a frequency corresponding to the frequency of the oscillatory motion of the liquid

  4. Co-registered photoacoustic, thermoacoustic, and ultrasound mouse imaging

    Science.gov (United States)

    Reinecke, Daniel R.; Kruger, Robert A.; Lam, Richard B.; DelRio, Stephen P.

    2010-02-01

    We have constructed and tested a prototype test bed that allows us to form 3D photoacoustic CT images using near-infrared (NIR) irradiation (700 - 900 nm), 3D thermoacoustic CT images using microwave irradiation (434 MHz), and 3D ultrasound images from a commercial ultrasound scanner. The device utilizes a vertically oriented, curved array to capture the photoacoustic and thermoacoustic data. In addition, an 8-MHz linear array fixed in a horizontal position provides the ultrasound data. The photoacoustic and thermoacoustic data sets are co-registered exactly because they use the same detector. The ultrasound data set requires only simple corrections to co-register its images. The photoacoustic, thermoacoustic, and ultrasound images of mouse anatomy reveal complementary anatomic information as they exploit different contrast mechanisms. The thermoacoustic images differentiate between muscle, fat and bone. The photoacoustic images reveal the hemoglobin distribution, which is localized predominantly in the vascular space. The ultrasound images provide detailed information about the bony structures. Superposition of all three images onto a co-registered hybrid image shows the potential of a trimodal photoacoustic-thermoacoustic-ultrasound small-animal imaging system.

  5. Heat Transfer in a Thermoacoustic Process

    Science.gov (United States)

    Beke, Tamas

    2012-01-01

    Thermoacoustic instability is defined as the excitation of acoustic modes in chambers with heat sources due to the coupling between acoustic perturbations and unsteady heat addition. The major objective of this paper is to achieve accurate theoretical results in a thermoacoustic heat transfer process. We carry out a detailed heat transfer analysis…

  6. Truck Thermoacoustic Generator and Chiller

    Energy Technology Data Exchange (ETDEWEB)

    Keolian, Robert

    2011-03-31

    This Final Report describes the accomplishments of the US Department of Energy (DOE) cooperative agreement project DE-FC26-04NT42113 - Truck Thermoacoustic Generator and Chiller - whose goal is to design, fabricate and test a thermoacoustic piezoelectric generator and chiller system for use on over-the-road heavy-duty-diesel trucks, driven alternatively by the waste heat of the main diesel engine exhaust or by a burner integrated into the thermoacoustic system. The thermoacoustic system would utilize engine exhaust waste heat to generate electricity and cab air conditioning, and would also function as an auxiliary power unit (APU) for idle reduction. The unit was to be tested in Volvo engine performance and endurance test cells and then integrated onto a Class 8 over-the-road heavy-duty-diesel truck for further testing on the road. The project has been a collaboration of The Pennsylvania State University Applied Research Laboratory, Los Alamos National Laboratory, Clean Power Resources Inc., and Volvo Powertrain (Mack Trucks Inc.). Cost share funding was provided by Applied Research Laboratory, and by Clean Power Resources Inc via its grant from Innovation Works - funding that was derived from the Commonwealth of Pennsylvania. Los Alamos received its funding separately through DOE Field Work Proposal 04EE09.

  7. Development of a 3 kW double-acting thermoacoustic Stirling electric generator

    International Nuclear Information System (INIS)

    Wu, Zhanghua; Yu, Guoyao; Zhang, Limin; Dai, Wei; Luo, Ercang

    2014-01-01

    Highlights: • A 3 kW double-acting thermoacoustic Stirling electric generator is introduced. • 1.57 kW electric power with 16.8% thermal-to-electric efficiency was achieved. • High mechanical damping coefficient greatly decreases the system performance. • Performance difference is significant, which also decreased system performance. - Abstract: In this paper, a double-acting thermoacoustic Stirling electric generator is proposed as a new device capable of converting external heat into electric power. In the system, at least three thermoacoustic Stirling heat engines and three linear alternators are used to build a multiple-cylinder electricity generator. In comparison with the conventional thermoacoustic electricity generation system, the double-acting thermoacoustic Stirling electric generator has advantages on efficiency, power density and power capacity. In order to verify the idea, a prototype of 3 kW three-cylinder double-acting thermoacoustic Stirling electric generator is designed, built and tested. Based on the classic thermoacoustic theory, numerical simulation is performed to obtain the thermodynamic parameters of the engine. And distributions of key parameters are presented for a better understanding of the energy conversion process in the engine. In the experiments, a maximum electric power of about 1.57 kW and a maximum thermal-to-electric conversion efficiency of 16.8% were achieved with 5 MPa pressurized helium and 86 Hz working frequency. However, we find that the mechanical damping coefficient of the piston is dramatically increased due to the deformation of the cylinder wall caused by high thermal stress during the experiments. Thereby, the system performance was greatly reduced. Additionally, the performance differences between three engines and three alternators are significant, such as the heating temperature difference between three heater blocks of the engines, the piston displacement and the output electric power differences between

  8. Thermoacoustic power systems for space applications

    International Nuclear Information System (INIS)

    Backhaus, S.N.; Tward, E.; Pedach, M.

    2001-01-01

    Future NASA deep-space missions will require radioisotope-powered electric generators that are just as reliable as current RTGs, but more efficient and of higher specific power (W/kg). Thermoacoustic engines can convert high-temperature heat into acoustic, or PV, power without moving parts at 30% efficiency. Consisting of only tubes and a few heat exchangers, these engines are low mass and promise to be highly reliable. Coupling a thermoacoustic engine to a low-mass, highly reliable and efficient linear alternator will create a heat-driven electric generator suitable for deep-space applications. Data will be presented on the first tests of a demonstration thermoacoustic engine designed for the 100-Watt power range.

  9. Physical modeling and characterization of thermo-acoustic loudspeakers made of silver nano-wire films

    Science.gov (United States)

    La Torraca, P.; Larcher, L.; Bobinger, M.; Pavan, P.; Seeber, B.; Lugli, P.

    2017-06-01

    Recent developments of ultra-low heat capacity nanostructured materials revived the interest in the thermo-acoustic (TA) loudspeaker technology, which shows important advantages compared to the classical dynamic loudspeakers as they feature a lower cost and weight, flexibility, conformability to the surface of various shapes, and transparency. The development of the TA loudspeaker technology requires accurate physical models connecting the material properties to the thermal and acoustic speaker's performance. We present here a combined theoretical and experimental analysis of TA loudspeakers, where the electro-thermal and the thermo-acoustic transductions are handled separately, thus allowing an in-depth description of both the pressure and temperature dynamics. The electro-thermal transduction is analyzed by accounting for all the heat flow processes taking place between the TA loudspeaker and the surrounding environment, with focus on their frequency dependence. The thermo-acoustic conversion is studied by solving the coupled thermo-acoustic equations, derived from the Navier-Stokes equations, and by exploiting the Huygens-Fresnel principle to decompose the TA loudspeaker surface into a dense set of TA point sources. A general formulation of the 3D pressure field is derived summing up the TA point source contributions via a Rayleigh integral. The model is validated against temperature and sound pressure level measured on the TA loudspeaker sample made of a Silver Nanowire random network deposited on a polyimide substrate. A good agreement is found between measurements and simulations, demonstrating that the model is capable of connecting material properties to the thermo-acoustic performance of the device, thus providing a valuable tool for the design and optimization of TA loudspeakers.

  10. Experimental investigation of a thermoacoustic-Stirling refrigerator driven by a thermoacoustic-Stirling heat engine.

    Science.gov (United States)

    Luo, E C; Dai, W; Zhang, Y; Ling, H

    2006-12-22

    In this paper, a thermally-driven thermoacoustic refrigerator system without any moving part is reported. This refrigeration system consists of a thermoacoustic-Stirling heat engine and a thermoacoustic-Stirling refrigerator; that is, the former is the driving source for the latter. Both the subsystems are designed to operate on traveling-wave mode. In the experiment, it was found that the DC-flows had significant negative effect on the heat engine and the refrigerator. To suppress these DC-flows, two flexible membranes were inserted into the two subsystems and worked very well. Then extensive experiments were made to test the influence of different parameters on refrigeration performance of the whole system. The system has so far achieved a no-load temperature of -65 degrees C, a cooling capacity of about 270 W at -20 degrees C and 405 W at 0 degrees C; in fact, the result showed a good prospect of the refrigeration system in room-temperature cooling such as food refrigeration and air-conditioning.

  11. Passive control of thermoacoustic oscillations with adjoint methods

    Science.gov (United States)

    Aguilar, Jose; Juniper, Matthew

    2017-11-01

    Strict pollutant regulations are driving gas turbine manufacturers to develop devices that operate under lean premixed conditions, which produce less NOx but encourage thermoacoustic oscillations. These are a form of unstable combustion that arise due to the coupling between the acoustic field and the fluctuating heat release in a combustion chamber. In such devices, in which safety is paramount, thermoacoustic oscillations must be eliminated passively, rather than through feedback control. The ideal way to eliminate thermoacoustic oscillations is by subtly changing the shape of the device. To achieve this, one must calculate the sensitivity of each unstable thermoacoustic mode to every geometric parameter. This is prohibitively expensive with standard methods, but is relatively cheap with adjoint methods. In this study we first present low-order network models as a tool to model and study the thermoacoustic behaviour of combustion chambers. Then we compute the continuous adjoint equations and the sensitivities to relevant parameters. With this, we run an optimization routine that modifies the parameters in order to stabilize all the resonant modes of a laboratory combustor rig.

  12. Theory and modeling of cylindrical thermo-acoustic transduction

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Lihong, E-mail: lhtong@ecjtu.edu.cn [School of Civil Engineering and Architecture, East China Jiaotong University, Nanchang, Jiangxi (China); Lim, C.W. [Department of Architecture and Civil Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR (China); Zhao, Xiushao; Geng, Daxing [School of Civil Engineering and Architecture, East China Jiaotong University, Nanchang, Jiangxi (China)

    2016-06-03

    Models both for solid and thinfilm-solid cylindrical thermo-acoustic transductions are proposed and the corresponding acoustic pressure solutions are obtained. The acoustic pressure for an individual carbon nanotube (CNT) as a function of input power is investigated analytically and it is verified by comparing with the published experimental data. Further numerical analysis on the acoustic pressure response and characteristics for varying input frequency and distance are also examined both for solid and thinfilm-solid cylindrical thermo-acoustic transductions. Through detailed theoretical and numerical studies on the acoustic pressure solution for thinfilm-solid cylindrical transduction, it is concluded that a solid with smaller thermal conductivity favors to improve the acoustic performance. In general, the proposed models are applicable to a variety of cylindrical thermo-acoustic devices performing in different gaseous media. - Highlights: • Theory and modeling both for solid and thinfilm-solid cylindrical thermo-acoustic transductions are proposed. • The modeling is verified by comparing with the published experimental data. • Acoustic response characteristics of cylindrical thermo-acoustic transductions are predicted by the proposed model.

  13. Design of a low-cost thermoacoustic electricity generator and its experimental verification

    Energy Technology Data Exchange (ETDEWEB)

    Backhaus, Scott N [Los Alamos National Laboratory; Yu, Z [UNIV OF MANCHESTER; Jaworski, A J [UNIV OF MANCHESTER

    2010-01-01

    This paper describes the design and testing of a low cost thermoacoustic generator. A travelling-wave thermoacoustic engine with a configuration of a looped-tube resonator is designed and constructed to convert heat to acoustic power. A commercially available, low-cost loudspeaker is adopted as the alternator to convert the engine's acoustic power to electricity. The whole system is designed using linear thermoacoustic theory. The optimization of different parts of the thermoacoustic generator, as well as the matching between the thermoacoustic engine and the alternator are discussed in detail. A detailed comparison between the preliminary test results and linear thermoacoustic predictions is provided.

  14. Modelling of Thermoacoustic Phenomena in an Electrically Heated Rijke Tube

    Science.gov (United States)

    Beke, Tamas

    2010-01-01

    Thermoacoustic instability plays an important role in various technical applications, for instance in jet or rocket motors, thermoacoustic engines, pulse combustors and industrial burners. The main objective of this paper is to present the theory of thermoacoustic oscillations, and for this purpose a Rijke-type thermal device was built. The Rijke…

  15. Acoustic field characteristics and performance analysis of a looped travelling-wave thermoacoustic refrigerator

    International Nuclear Information System (INIS)

    Jin, T.; Yang, R.; Wang, Y.; Feng, Y.; Tang, K.

    2016-01-01

    Highlights: • Key issues for a highly efficient thermoacoustic conversion are analyzed. • A looped thermoacoustic refrigerator with one engine stage and one refrigerator stage is proposed. • Effective refrigeration powered by heat sources below 250 °C is demonstrated in the simulation. • Impact of cooling/heating temperatures on system performance is analyzed in view of acoustic field. - Abstract: This paper focuses on a looped travelling-wave thermoacoustic refrigerator powered by thermal energy. Based on a simplified model for the regenerator, key issues for a highly efficient thermoacoustic conversion, including both thermal-to-acoustic and heat-pumping processes, are summarized. A looped travelling-wave thermoacoustic refrigerator with one engine stage and one refrigerator stage is proposed, with emphasis on high normalized acoustic impedance, sufficient volumetric velocity and appropriate phase relation close to travelling wave in the regenerators of both engine and refrigerator. Simulation results indicate that for the ambient temperature of 30 °C, the looped travelling-wave thermoacoustic refrigerator can be powered by the heat at 210–250 °C to achieve the refrigeration at −3 °C with the overall coefficient of performance above 0.4 and the relative Carnot coefficient of performance over 13%. The characteristics of the acoustic field inside the loop configuration are analyzed in detail to reveal the operation mechanism of the looped travelling-wave thermoacoustic refrigerator. Additional analyses are conducted on the impact of the cooling and the heating temperatures, which are of great concern to the refrigeration applications and the utilization of low-grade thermal energy.

  16. Investigation on thermo-acoustic instability dynamic characteristics of hydrocarbon fuel flowing in scramjet cooling channel based on wavelet entropy method

    Science.gov (United States)

    Zan, Hao; Li, Haowei; Jiang, Yuguang; Wu, Meng; Zhou, Weixing; Bao, Wen

    2018-06-01

    As part of our efforts to find ways and means to further improve the regenerative cooling technology in scramjet, the experiments of thermo-acoustic instability dynamic characteristics of hydrocarbon fuel flowing have been conducted in horizontal circular tubes at different conditions. The experimental results indicate that there is a developing process from thermo-acoustic stability to instability. In order to have a deep understanding on the developing process of thermo-acoustic instability, the method of Multi-scale Shannon Wavelet Entropy (MSWE) based on Wavelet Transform Correlation Filter (WTCF) and Multi-Scale Shannon Entropy (MSE) is adopted in this paper. The results demonstrate that the developing process of thermo-acoustic instability from noise and weak signals is well detected by MSWE method and the differences among the stability, the developing process and the instability can be identified. These properties render the method particularly powerful for warning thermo-acoustic instability of hydrocarbon fuel flowing in scramjet cooling channels. The mass flow rate and the inlet pressure will make an influence on the developing process of the thermo-acoustic instability. The investigation on thermo-acoustic instability dynamic characteristics at supercritical pressure based on wavelet entropy method offers guidance on the control of scramjet fuel supply, which can secure stable fuel flowing in regenerative cooling system.

  17. Coincident effect characteristic in a thermoacoustic regenerator

    International Nuclear Information System (INIS)

    Liu Yicai; Xin Tianlong; Huang Qian; Shi Xiangnan; Chen Siming; Chen Lixin

    2011-01-01

    Many previous studies on characteristics of thermoacoustic regenerator are based on fluid micro-groups and their compression-expansion cycle. In this paper, coincident frequency is introduced to evaluate its acoustic characteristics by combining structural acoustic with structural vibration theories. The relationship among structure wave radiation and regenerator position, slab thickness, and properties of material are analyzed by numerical calculation. The results show that in the low-frequency thermoacoustic system, the coincident effect generated by higher frequency wave weakens the fundamental sound wave. While in the high-frequency thermoacoustic system, where the oscillating fundamental frequency is higher than the coincident frequency, the sound field strength is enhanced by stronger structure wave radiation because of the coincident effect.

  18. The feasibility of using microwave-induced thermoacoustic tomography for detection and evaluation of renal calculi

    International Nuclear Information System (INIS)

    Cao Caijun; Nie Liming; Lou Cunguang; Xing Da

    2010-01-01

    Imaging of renal calculi is important for patients who suffered a urinary calculus prior to treatment. The available imaging techniques include plain x-ray, ultrasound scan, intravenous urogram, computed tomography, etc. However, the visualization of a uric acid calculus (radiolucent calculi) is difficult and often impossible by the above imaging methods. In this paper, a new detection method based on microwave-induced thermoacoustic tomography was developed to detect the renal calculi. Thermoacoustic images of calcium oxalate and uric acid calculus were compared with their x-ray images. The microwave absorption differences among the calcium oxalate calculus, uric acid calculus and normal kidney tissue could be evaluated by the amplitude of the thermoacoustic signals. The calculi hidden in the swine kidney were clearly imaged with excellent contrast and resolution in the three orthogonal thermoacoustic images. The results indicate that thermoacoustic imaging may be developed as a complementary method for detecting renal calculi, and its low cost and effective feature shows high potential for clinical applications.

  19. A numerical simulation method and analysis of a complete thermoacoustic-Stirling engine.

    Science.gov (United States)

    Ling, Hong; Luo, Ercang; Dai, Wei

    2006-12-22

    Thermoacoustic prime movers can generate pressure oscillation without any moving parts on self-excited thermoacoustic effect. The details of the numerical simulation methodology for thermoacoustic engines are presented in the paper. First, a four-port network method is used to build the transcendental equation of complex frequency as a criterion to judge if temperature distribution of the whole thermoacoustic system is correct for the case with given heating power. Then, the numerical simulation of a thermoacoustic-Stirling heat engine is carried out. It is proved that the numerical simulation code can run robustly and output what one is interested in. Finally, the calculated results are compared with the experiments of the thermoacoustic-Stirling heat engine (TASHE). It shows that the numerical simulation can agrees with the experimental results with acceptable accuracy.

  20. A linearly-acting variable-reluctance generator for thermoacoustic engines

    International Nuclear Information System (INIS)

    Hail, Claudio U.; Knodel, Philip C.; Lang, Jeffrey H.; Brisson, John G.

    2015-01-01

    Highlights: • A new design for a linear alternator for thermoacoustic power converters is presented. • A theoretical and semi-empirical model of the generator is developed and validated. • The variable-reluctance generator’s performance is experimentally characterized. • Scaling to higher frequency suggests efficient operation with thermoacoustic engines. - Abstract: A crucial element in a thermoacoustic power converter for reliable small-scale power generation applications is an efficient acoustic-to-electric energy converter. In this work, an acoustic-to-electric transducer for application with a back-to-back standing wave thermoacoustic engine, based on a linearly-acting variable-reluctance generator is proposed, built and experimentally tested. Static and dynamic experiments are performed on one side of the generator on a shaker table at 60 Hz with 5 mm peak-to-peak displacement for performance characterization. A theoretical and empirical model of the variable-reluctance generator are presented and validated with experimental data. A frequency scaling based on the empirical model indicates that a maximum power output of 84 W at 78% generator efficiency is feasible at the thermoacoustic engine’s operating frequency of 250 Hz, not considering power electronic losses. This suggests that the linearly-acting variable-reluctance generator can efficiently convert high frequency small amplitude acoustic oscillations to useful electricity and thus enables its integration into a thermoacoustic power converter

  1. Thermoacoustic emission induced by deeply-penetrating radiation and its application to biomedical imaging

    International Nuclear Information System (INIS)

    Liew, Soo Chin.

    1989-01-01

    Thermoacoustic emissions induced by 2450 MHz microwave pulses in water, tissue-simulating phantoms and dog kidneys have been detected. The analytic signal magnitude has been employed in generating A-mode images with excellent depth resolution. Thermoacoustic emissions have also been detected from the dose-gradient at the beam edges of a 4 MeV x-ray beam in water. These results establish the feasibility of employing thermoacoustic signals in generating diagnostic images, and in locating x-ray beam edges during radiation therapy. A theoretical model for thermoacoustic imaging using a directional transducer has been developed, which may be used in the design of future thermoacoustic imaging system, and in facilitating comparisons with other types of imaging systems. A method of characterizing biological tissues has been proposed, which relates the power spectrum of the detected thermoacoustic signals to the autocorrelation function of the thermoacoustic source distribution in the tissues. The temperature dependence of acoustic signals induced by microwave pulses in water has been investigated. A microwave-induced thermoacoustic source capable of launching large aperture, unipolar ultrasonic plane wave pulses in water has been constructed

  2. Thermoacoustics of solids: A pathway to solid state engines and refrigerators

    Science.gov (United States)

    Hao, Haitian; Scalo, Carlo; Sen, Mihir; Semperlotti, Fabio

    2018-01-01

    Thermoacoustic oscillations have been one of the most exciting discoveries of the physics of fluids in the 19th century. Since its inception, scientists have formulated a comprehensive theoretical explanation of the basic phenomenon which has later found several practical applications to engineering devices. To date, all studies have concentrated on the thermoacoustics of fluid media where this fascinating mechanism was exclusively believed to exist. Our study shows theoretical and numerical evidence of the existence of thermoacoustic instabilities in solid media. Although the underlying physical mechanism exhibits some interesting similarities with its counterpart in fluids, the theoretical framework highlights relevant differences that have important implications on the ability to trigger and sustain the thermoacoustic response. This mechanism could pave the way to the development of highly robust and reliable solid-state thermoacoustic engines and refrigerators.

  3. Traveling-Wave Thermoacoustic Engines With Internal Combustion

    Science.gov (United States)

    Weiland, Nathan Thomas; Zinn, Ben T.; Swift, Gregory William

    2004-05-11

    Thermoacoustic devices are disclosed wherein, for some embodiments, a combustion zone provides heat to a regenerator using a mean flow of compressible fluid. In other embodiments, burning of a combustible mixture within the combustion zone is pulsed in phase with the acoustic pressure oscillations to increase acoustic power output. In an example embodiment, the combustion zone and the regenerator are thermally insulated from other components within the thermoacoustic device.

  4. Evaluation of thermal efficiency and energy conversion of thermoacoustic Stirling engines

    International Nuclear Information System (INIS)

    Zhong Junhu; Zheng Yuli; Qing Li; Qiang Li

    2010-01-01

    Thermodynamic cycle transferring heat and work was executed in thermoacoustic engines, when the acoustic resonators substituted the moving mechanical components of the traditional heat engines. Based on the traveling-wave phasing and reversible heat transfer, thermoacoustic Stirling engines could achieve 70% of the Carnot efficiency theoretically, if the inevitable viscous dissipation in resonators was also counted as exported power. It should be pointed out an error on this efficiency evaluation in the previous literatures. More than 70% of the acoustic power production was often consumed by the side-branch resonator that was the essential configuration to build up a thermoacoustic Stirling engine. According to the simulation results and some experimental data, the actual available acoustic power consumed by the acoustic loads was restricted by the operating peak-to-mean pressure ratio, i.e. |p 1 /p m |. When the peak-to-mean pressure ratio operated on 4-6.5%, the thermal efficiency and power density of the available acoustic power reached higher levels. But the available acoustic power would approach zero when |p 1 /p m | attained 10%. It was approved that the turbulence oscillation occurred on the higher |p 1 /p m | (usually >4%) was the main reason of the excess dissipation in the side-branch resonator. This character of the available power limited the wide application of thermoacoustic Stirling engines. The evaluation of thermal efficiency and energy conversion also indicated the improving direction of thermoacoustic Stirling engines. Generators driven by the thermoacoustic Stirling engines were an effective way, due to the elimination of the side-branch resonator. To achieve a high power density and a high pressure ratio on the higher available power efficiency level, the standing-wave thermoacoustic engines might outvie the traveling-wave thermoacoustic engines. To enjoy the best features of standing-wave engines and traveling-wave engines simultaneously

  5. Theoretical and experimental study of thermoacoustic engines

    Science.gov (United States)

    Raspet, Richard; Bass, Henry E.; Arnott, W. P.

    1992-12-01

    A three year study of thermoacoustic engines operating as prime movers and refrigerators was completed. The major thrust of this effort was the use and theoretical description of ceramic honeycomb structures as the active element in thermoacoustic engines. An air-filled demonstration prime mover was constructed and demonstrated at Acoustical Society of America and IEE meetings. A helium-filled test prime mover was designed and built an is being employed in studies of the threshold of oscillation as a function of temperature difference and pressure. In addition, acoustically based theories of the thermoacoustic engine have been developed and tested for a parallel plate stack at the Naval Postgraduate School and for a honeycomb stack at the University of Mississippi. Most of this work is described in detail in the attached publications. In this report we will give an overview of the research completed to date and its relationship to work performed at the Naval Postgraduate School and to future work at the University of Mississippi.

  6. Optimizing the Thermoacoustic Pulse Tube Refrigerator Performances

    Directory of Open Access Journals (Sweden)

    E. V. Blagin

    2014-01-01

    Full Text Available The article deals with research and optimization of the thermoacoustic pulse tube refrigerator to reach a cryogenic temperature level. The refrigerator is considered as a thermoacoustic converter based on the modified Stirling cycle with helium working fluid. A sound pressure generator runs as a compressor. Plant model comprises an inner heat exchanger, a regenerative heat exchanger, a pulse tube, hot and cold heat exchangers at its ends, an inertial tube with the throttle, and a reservoir. A model to calculate the pulse tube thermoacoustic refrigerator using the DeltaEC software package has been developed to be a basis for calculation techniques of the pulse tube refrigerator. Momentum, continuity, and energy equations for helium refrigerant are solved according to calculation algorithm taking into account the porosity of regenerator and heat exchangers. Optimization of the main geometric parameters resulted in decreasing temperature of cold heat exchanger by 41,7 K. After optimization this value became equal to 115,01 K. The following parameters have been optimized: diameters of the feeding and pulse tube and heat exchangers, regenerator, lengths of the regenerator and pulse and inertial tubes, as well as initial pressure. Besides, global minimum of temperatures has been searched at a point of local minima corresponding to the optimal values of abovementioned parameters. A global-local minima difference is 0,1%. Optimized geometric and working parameters of the thermoacoustic pulse tube refrigerator are presented.

  7. Design of numerical model for thermoacoustic devices using OpenFOAM

    Science.gov (United States)

    Tisovsky, Tomas; Vit, Tomas

    2017-09-01

    Thermoacoustic devices are increasingly popular especially because of their construction simplicity and the ability to easily convert waste heat into the form of usable energy. Aim of this paper is to introduce some of the effective procedures for creating a complex mathematical model of thermoacoustic devices in OpenFOAM.

  8. Thermoacoustic engines and refrigerators

    Energy Technology Data Exchange (ETDEWEB)

    Swift, G.

    1996-12-31

    This report is a transcript of a practice lecture given in preparation for a review lecture on the operation of thermoacoustic engines and refrigerators. The author begins by a brief review of the thermodynamic principles underlying the operation of thermoacoustic engines and refrigerators. Remember from thermodynamics class that there are two kinds of heat engines, the heat engine or the prime mover which produces work from heat, and the refrigerator or heat pump that uses work to pump heat. The device operates between two thermal reservoirs at temperatures T{sub hot} and T{sub cold}. In the heat engine, heat flows into the device from the reservoir at T{sub hot}, produces work, and delivers waste heat into the reservoir at T{sub cold}. In the refrigerator, work flows into the device, lifting heat Q{sub cold} from reservoir at T{sub cold} and rejecting waste heat into the reservoir at T{sub hot}.

  9. Forced synchronization and asynchronous quenching in a thermo-acoustic system

    Science.gov (United States)

    Mondal, Sirshendu; Pawar, Samadhan A.; Sujith, Raman

    2017-11-01

    Forced synchronization, which has been extensively studied in theory and experiments, occurs through two different mechanisms known as phase locking and asynchronous quenching. The latter indicates the suppression of oscillation amplitude. In most practical combustion systems such as gas turbine engines, the main concern is high amplitude pressure oscillations, known as thermo-acoustic instability. Thermo-acoustic instability is undesirable and needs to be suppressed because of its damaging consequences to an engine. In the present study, a systematic experimental investigation of forced synchronization is performed in a prototypical thermo-acoustic system, a Rijke tube, in its limit cycle operation. Further, we show a qualitatively similar behavior using a reduced order model. In the phase locking region, the simultaneous occurrence of synchronization and resonant amplification leads to high amplitude pressure oscillations. However, a reduction in the amplitude of natural oscillations by about 78% of the unforced amplitude is observed when the forcing frequency is far lower than the natural frequency. This shows the possibility of suppression of the oscillation amplitude through asynchronous quenching in thermo-acoustic systems.

  10. Generation of thermo-acoustic waves from pulsed solar/IR radiation

    Science.gov (United States)

    Rahman, Aowabin

    Acoustic waves could potentially be used in a wide range of engineering applications; however, the high energy consumption in generating acoustic waves from electrical energy and the cost associated with the process limit the use of acoustic waves in industrial processes. Acoustic waves converted from solar radiation provide a feasible way of obtaining acoustic energy, without relying on conventional nonrenewable energy sources. One of the goals of this thesis project was to experimentally study the conversion of thermal to acoustic energy using pulsed radiation. The experiments were categorized into "indoor" and "outdoor" experiments, each with a separate experimental setup. The indoor experiments used an IR heater to power the thermo-acoustic lasers and were primarily aimed at studying the effect of various experimental parameters on the amplitude of sound waves in the low frequency range (below 130 Hz). The IR radiation was modulated externally using a chopper wheel and then impinged on a porous solid, which was housed inside a thermo-acoustic (TA) converter. A microphone located at a certain distance from the porous solid inside the TA converter detected the acoustic signals. The "outdoor" experiments, which were targeted at TA conversion at comparatively higher frequencies (in 200 Hz-3 kHz range) used solar energy to power the thermo-acoustic laser. The amplitudes (in RMS) of thermo-acoustic signals obtained in experiments using IR heater as radiation source were in the 80-100 dB range. The frequency of acoustic waves corresponded to the frequency of interceptions of the radiation beam by the chopper. The amplitudes of acoustic waves were influenced by several factors, including the chopping frequency, magnitude of radiation flux, type of porous material, length of porous material, external heating of the TA converter housing, location of microphone within the air column, and design of the TA converter. The time-dependent profile of the thermo-acoustic signals

  11. Open-loop control of quasiperiodic thermoacoustic oscillations

    Science.gov (United States)

    Guan, Yu; Gupta, Vikrant; Kashinath, Karthik; Li, Larry K. B.

    2017-11-01

    The open-loop application of periodic acoustic forcing has been shown to be a potentially effective strategy for controlling periodic thermoacoustic oscillations, but its effectiveness on aperiodic thermoacoustic oscillations is less clear. In this experimental study, we apply periodic acoustic forcing to a ducted premixed flame oscillating quasiperiodically at two incommensurate natural frequencies, f1 and f2. We find that (i) above a critical forcing amplitude, the system locks into the forcing by oscillating only at the forcing frequency ff, producing a closed periodic orbit in phase space with no evidence of the original T2 torus attractor; (ii) the critical forcing amplitude required for lock-in decreases as ff approaches either f1 or f2, resulting in characteristic ∨-shaped lock-in boundaries around the two natural modes; and (iii) for a wide range of forcing frequencies, the system's oscillation amplitude can be reduced to less than 20% of that of the unforced system. These findings show that the open-loop application of periodic acoustic forcing can be an effective strategy for controlling aperiodic thermoacoustic oscillations. This work was supported by the Research Grants Council of Hong Kong (Project No. 16235716 and 26202815).

  12. A multi-stage traveling-wave thermoacoustically-driven refrigeration system operating at liquefied natural gas temperature

    Science.gov (United States)

    Luo, K.; Sun, D. M.; Zhang, J.; Shen, Q.; Zhang, N.

    2017-12-01

    This study proposes a multi-stage travelling-wave thermoacoustically refrigeration system (TAD-RS) operating at liquefied natural gas temperature, which consists of two thermoacoustic engines (TAE) and one thermoacoustic refrigerator (TAR) in a closed-loop configuration. Three thermoacoustic units connect each other through a resonance tube of small cross-sectional area, achieving “self-matching” for efficient thermoacoustic conversion. Based on the linear thermoacoustic theory, a model of the proposed system has been built by using DeltaEC program to show the acoustic field characteristics and performance. It is shown that with pressurized 5 MPa helium as working gas, the TAEs are able to build a stable and strong acoustic field with a frequency of about 85 Hz. When hot end temperature reaches 923 K, this system can provide about 1410 W cooling power at 110 K with an overall exergy efficiency of 15.5%. This study indicates a great application prospect of TAD-RS in the field of natural gas liquefaction with a large cooling capacity and simple structure.

  13. Performance measurement of a mini thermoacoustic refrigerator and associated drivers

    OpenAIRE

    Petrina, Denys E.

    2002-01-01

    Approved for public release; distribution is unlimited A miniature Thermoacoustic refrigerator is being developed to cool integrated circuits - which must sometimes operate at high temperatures nearing the upper threshold of their tolerance - to temperature spans more within the circuits' tolerable limits, without the need of the chemicals of a traditional refrigerating system. The development of an electrically powered acoustic driver that powers the thermoacoustic refrigerator is describ...

  14. Method of determination of thermo-acoustic coolant instability boundaries in reactor core at NPPs with WWER

    International Nuclear Information System (INIS)

    Skalozubov, Volodymyr; Kolykhanov, Viktor; Kovryzhkin, Yuriy

    2007-01-01

    The regulatory body of Ukraine, the National Atomic Energy Company and the Scientific and Production Centre have led team-works concerned with previously unstudied factors or phenomena affecting reactor safety. As a result it is determined that the thermo-acoustic coolant instability conditions can appear in the core at definite operating WWER regimes. Considerable cyclic dynamic loads affect fuel claddings over thermo-acoustic pressure oscillations. These loads can result in inadmissible cassette design damage and containment damage. Taking into account calculation and experimental research authors submit a method of on-line assessment of WWER core state concerning thermo-acoustic coolant instability. According to this method, the thermo-acoustic coolant instability appearance conditions can be estimated using normal registered parameters (pressure, temperature, heat demand etc.). At operative modes, a WWER-1000 core is stable to tracheotomies oscillations, but reduction of coolant discharge through the core for some times can result in thermo-acoustic coolant instability. Thermo-acoustic instability appears at separate transitional modes concerned with reactor scram and unloading/loading at all power units. When thermo-acoustic instability begins in transitional modes, core elements are under influence of high-frequency coolant pressure pulsations for a long time (tens of hours)

  15. A Thermoacoustic Model for High Aspect Ratio Nanostructures

    Directory of Open Access Journals (Sweden)

    Masoud S. Loeian

    2016-09-01

    Full Text Available In this paper, we have developed a new thermoacoustic model for predicting the resonance frequency and quality factors of one-dimensional (1D nanoresonators. Considering a nanoresonator as a fix-free Bernoulli-Euler cantilever, an analytical model has been developed to show the influence of material and geometrical properties of 1D nanoresonators on their mechanical response without any damping. Diameter and elastic modulus have a direct relationship and length has an inverse relationship on the strain energy and stress at the clamp end of the nanoresonator. A thermoacoustic multiphysics COMSOL model has been elaborated to simulate the frequency response of vibrating 1D nanoresonators in air. The results are an excellent match with experimental data from independently published literature reports, and the results of this model are consistent with the analytical model. Considering the air and thermal damping in the thermoacoustic model, the quality factor of a nanowire has been estimated and the results show that zinc oxide (ZnO and silver-gallium (Ag2Ga nanoresonators are potential candidates as nanoresonators, nanoactuators, and for scanning probe microscopy applications.

  16. Exergetic optimization of a thermoacoustic engine using the particle swarm optimization method

    International Nuclear Information System (INIS)

    Chaitou, Hussein; Nika, Philippe

    2012-01-01

    Highlights: ► Optimization of a thermoacoustic engine using the particle swarm optimization method. ► Exergetic efficiency, acoustic power and their product are the optimized functions. ► PSO method is used successfully for the first time in the TA research. ► The powerful PSO tool is advised to be more involved in the TA research and design. ► EE times AP optimized function is highly recommended to design any new TA devices. - Abstract: Thermoacoustic engines convert heat energy into acoustic energy. Then, the acoustic energy can be used to pump heat or to generate electricity. It is well-known that the acoustic energy and therefore the exergetic efficiency depend on parameters such as the stack’s hydraulic radius, the stack’s position in the resonator and the traveling–standing-wave ratio. In this paper, these three parameters are investigated in order to study and analyze the best value of the produced acoustic energy, the exergetic efficiency and the product of the acoustic energy by the exergetic efficiency of a thermoacoustic engine with a parallel-plate stack. The dimensionless expressions of the thermoacoustic equations are derived and calculated. Then, the Particle Swarm Optimization method (PSO) is introduced and used for the first time in the thermoacoustic research. The use of the PSO method and the optimization of the acoustic energy multiplied by the exergetic efficiency are novel contributions to this domain of research. This paper discusses some significant conclusions which are useful for the design of new thermoacoustic engines.

  17. Control of thermoacoustic instability with a drum-like silencer

    Science.gov (United States)

    Zhang, Guangyu; Wang, Xiaoyu; Li, Lei; Jing, Xiaodong; Sun, Xiaofeng

    2017-10-01

    Theoretical investigation is carried out by a novel method of controlling thermoacoustic instability with a drum-like silencer. It is shown that by decreasing the frequency of thermoacoustic system, the instability can be suppressed with the help of drum-like silencer. The purely reactive silencer, which is composed of a flexible membrane and a backing cavity, is usually known as a noise control device that works effectively in low frequency bandwidth without any aerodynamic loss. In present research, the silencer is exploited in a Rijke tube, as a means of decreasing the natural frequency of the system, and consequently changing the resonance period of the system. The "transfer element method" (TEM) is used to consider the interactions between the acoustic waves and the flexible membranes of the silencer. The effects of all possible properties of the silencer on the growth rate and resonance frequency of the thermoacoustic system are explored. According to the calculation results, it is found that for some properties of the silencer, the resonance frequencies are greatly decreased and then the phase difference between the unsteady heat release and the pressure fluctuation is increased. Consequently, the instability is suppressed with some dissipation that can not be able to control its onset in the original system. Therefore, when the damping is low, but not zero, it is effective to control thermoacoustic instability with this technique.

  18. A one-dimensional heat transfer model for parallel-plate thermoacoustic heat exchangers.

    Science.gov (United States)

    de Jong, J A; Wijnant, Y H; de Boer, A

    2014-03-01

    A one-dimensional (1D) laminar oscillating flow heat transfer model is derived and applied to parallel-plate thermoacoustic heat exchangers. The model can be used to estimate the heat transfer from the solid wall to the acoustic medium, which is required for the heat input/output of thermoacoustic systems. The model is implementable in existing (quasi-)1D thermoacoustic codes, such as DeltaEC. Examples of generated results show good agreement with literature results. The model allows for arbitrary wave phasing; however, it is shown that the wave phasing does not significantly influence the heat transfer.

  19. Thermoacoustics a unifying perspective for some engines and refrigerators

    CERN Document Server

    Swift, Gregory W

    2017-01-01

    This updated new edition provides an introduction to the field of thermoacoustics. All of the key aspects of the topic are introduced, with the goal of helping the reader to acquire both an intuitive understanding and the ability to design hardware, build it, and assess its performance. Weaving together intuition, mathematics, and experimental results, this text equips readers with the tools to bridge the fields of thermodynamics and acoustics. At the same time, it remains firmly grounded in experimental results, basing its discussions on the distillation of a body of experiments spanning several decades and countries. The book begins with detailed treatment of the fundamental physical laws that underlie thermoacoustics. It then goes on to discuss key concepts, including simple oscillations, waves, power, and efficiency. The remaining portions of the book delve into more advanced topics and address practical concerns in applications  chapters on hardware and m easurements. With its careful progression and e...

  20. A hot air driven thermoacoustic-Stirling engine

    Energy Technology Data Exchange (ETDEWEB)

    Tijani, M.E.H.; Spoelstra, S. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2012-09-15

    Significant energy savings can be obtained by implementing a thermally driven heat pump into industrial or domestic applications. Such a thermally driven heat pump uses heat from a high-temperature source to drive the system which upgrades an abundantly available heat source (industrial waste heat, air, water, geothermal). A way to do this is by coupling a thermoacoustic engine with a thermoacoustic heat pump. The engine is driven by a burner and produces acoustic power and heat at the required temperature. The acoustic power is used to pump heat in the heat pump to the required temperature. This system is attractive since it uses a noble gas as working medium and has no moving mechanical parts. This paper deals with the first part of this system: the engine. In this study, hot air is used to simulate the flue gases originating from a gas burner. This is in contrast with a lot of other studies of thermoacoustic engines that use an electrical heater as heat source. Using hot air resembles to a larger extent the real world application. The engine produces about 300W of acoustic power with a performance of 41% of the Carnot efficiency at a hot air temperature of 620C.

  1. A one-dimensional heat transfer model for parallel-plate thermoacoustic heat exchangers

    NARCIS (Netherlands)

    de Jong, Anne; Wijnant, Ysbrand H.; de Boer, Andries

    2014-01-01

    A one-dimensional (1D) laminar oscillating flow heat transfer model is derived and applied to parallel-plate thermoacoustic heat exchangers. The model can be used to estimate the heat transfer from the solid wall to the acoustic medium, which is required for the heat input/output of thermoacoustic

  2. Thermoacoustic Emission Induced by Deeply-Penetrating Radiation and its Application to Biomedical Imaging.

    Science.gov (United States)

    Liew, Soo Chin

    Thermoacoustic emissions induced by 2450 MHz microwave pulses in water, tissue-simulating phantoms and dog kidneys have been detected. The analytic signal magnitude has been employed in generating 'A-mode' images with excellent depth resolution. Thermoacoustic emissions have also been detected from the dose-gradient at the beam edges of a 4 MeV x-ray beam in water. These results establish the feasibility of employing thermoacoustic signals in generating diagnostic images, and in locating x-ray beam edges during radiation therapy. A theoretical model for thermoacoustic imaging using a directional transducer has been developed, which may be used in the design of future thermoacoustic imaging system, and in facilitating comparisons with other types of imaging systems. A method of characterizing biological tissues has been proposed, which relates the power spectrum of the detected thermoacoustic signals to the autocorrelation function of the thermoacoustic source distribution in the tissues. The temperature dependence of acoustic signals induced by microwave pulses in water has been investigated. The signal amplitudes vary with temperature as the thermal expansion of water, except near 4^circ C. The signal waveforms show a gradual phase change as the temperature changes from below 4^ circ to above 4^circ C. This anomaly is due to the presence of a nonthermal component detected near 4^circC, whose waveform is similar to the derivative of the room temperature signal. The results are compared to a model based on a nonequilibrium relaxation mechanism proposed by Pierce and Hsieh. The relaxation time was found to be (0.20 +/- 0.02) ns and (0.13 +/- 0.02) ns for 200 ns and 400 ns microwave pulse widths, respectively. A microwave-induced thermoacoustic source capable of launching large aperture, unipolar ultrasonic plane wave pulses in water has been constructed. This source consists of a thin water layer trapped between two dielectric media. Due to the large mismatch in the

  3. Experimental Investigation of Bifurcations in a Thermoacoustic Engine

    Directory of Open Access Journals (Sweden)

    Vishnu R. Unni

    2015-06-01

    Full Text Available In this study, variation in the characteristics of the pressure oscillations in a thermoacoustic engine is explored as the input heat flux is varied. A bifurcation diagram is plotted to study the variation in the qualitative behavior of the acoustic oscillations as the input heat flux changes. At a critical input heat flux (60 Watt, the engine begins to produce acoustic oscillations in its fundamental longitudinal mode. As the input heat flux is increased, incommensurate frequencies appear in the power spectrum. The simultaneous presence of incommensurate frequencies results in quasiperiodic oscillations. On further increase of heat flux, the fundamental mode disappears and second mode oscillations are observed. These bifurcations in the characteristics of the pressure oscillations are the result of nonlinear interaction between multiple modes present in the thermoacoustic engine. Hysteresis in the bifurcation diagram suggests that the bifurcation is subcritical. Further, the qualitative analysis of different dynamic regimes is performed using nonlinear time series analysis. The physical reason for the observed nonlinear behavior is discussed. Suggestions to avert the variations in qualitative behavior of the pressure oscillations in thermoacoustic engines are also provided.

  4. Modeling of micro-scale thermoacoustics

    Energy Technology Data Exchange (ETDEWEB)

    Offner, Avshalom [The Nancy and Stephen Grand Technion Energy Program, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Department of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Ramon, Guy Z., E-mail: ramong@technion.ac.il [Department of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa 32000 (Israel)

    2016-05-02

    Thermoacoustic phenomena, that is, onset of self-sustained oscillations or time-averaged fluxes in a sound wave, may be harnessed as efficient and robust heat transfer devices. Specifically, miniaturization of such devices holds great promise for cooling of electronics. At the required small dimensions, it is expected that non-negligible slip effects exist at the solid surface of the “stack”-a porous matrix, which is used for maintaining the correct temporal phasing of the heat transfer between the solid and oscillating gas. Here, we develop theoretical models for thermoacoustic engines and heat pumps that account for slip, within the standing-wave approximation. Stability curves for engines with both no-slip and slip boundary conditions were calculated; the slip boundary condition curve exhibits a lower temperature difference compared with the no slip curve for resonance frequencies that characterize micro-scale devices. Maximum achievable temperature differences across the stack of a heat pump were also calculated. For this case, slip conditions are detrimental and such a heat pump would maintain a lower temperature difference compared to larger devices, where slip effects are negligible.

  5. Modeling of micro-scale thermoacoustics

    International Nuclear Information System (INIS)

    Offner, Avshalom; Ramon, Guy Z.

    2016-01-01

    Thermoacoustic phenomena, that is, onset of self-sustained oscillations or time-averaged fluxes in a sound wave, may be harnessed as efficient and robust heat transfer devices. Specifically, miniaturization of such devices holds great promise for cooling of electronics. At the required small dimensions, it is expected that non-negligible slip effects exist at the solid surface of the “stack”-a porous matrix, which is used for maintaining the correct temporal phasing of the heat transfer between the solid and oscillating gas. Here, we develop theoretical models for thermoacoustic engines and heat pumps that account for slip, within the standing-wave approximation. Stability curves for engines with both no-slip and slip boundary conditions were calculated; the slip boundary condition curve exhibits a lower temperature difference compared with the no slip curve for resonance frequencies that characterize micro-scale devices. Maximum achievable temperature differences across the stack of a heat pump were also calculated. For this case, slip conditions are detrimental and such a heat pump would maintain a lower temperature difference compared to larger devices, where slip effects are negligible.

  6. Thermoacoustic refrigerators : experiments and scaling analysis

    NARCIS (Netherlands)

    Li, Y.

    2011-01-01

    Thermoacoustics, as the word spelling indicates, is an interdisciplinary field in physics. Both acoustics and thermodynamics are involved in the description of this interesting phenomenon. When a solid wall is present in direction of the wave vector of an acoustic field, the interaction between the

  7. Mean temperature profile at the entrance of a thermoacoustic stacked screen heat exchanger

    NARCIS (Netherlands)

    Bühler, Simon; wilcox, D; Oosterhuis, Joris; van der Meer, Theodorus H.

    2015-01-01

    In thermoacoustic devises, the thermoacoustic e ect occurs in the regenerator placed between two heat exchangers. The entrance e ects of such heat exchanger are investigated with two computational uid dynamics (CFD) test cases. The rst CFD test case models an ideal heat exchanger adjacent to an open

  8. Phase-exchange thermoacoustic engine

    Science.gov (United States)

    Offner, Avshalom; Meir, Avishai; Ramon, Guy Z.; WET Lab Team

    2017-11-01

    Phase-exchange thermoacoustic engines are reliable machines holding great promise in converting heat from low grade heat sources to mechanical or electrical power. In these engines the working fluid is a gas mixture containing one condensable component, decreasing the temperature difference required for ignition and steady state operation. Our experimental setup consists of a vertical acoustic resonator containing a mixture of air-water vapor. Water evaporates near the heat source, condenses at the heat sink and is drawn back down by gravity and capillary forces where it re-evaporates, sustaining a steady state closed thermodynamic cycle. We investigated the stability limit, namely the critical point at which temperature difference in the engine enables onset of self-excited oscillations, and the steady state of the engine. A simple theoretical model was derived, describing mechanisms of irreversible entropy generation and production of acoustic power in such engines. This model captures the essence in the differences between regular and phase-exchange thermoacoustic engines, and shows good agreement with experimental results of stability limit. Steady state results reveal not only a dramatic decrease in temperature difference, but also an increase in engine performances. The authors acknowledge the support from the Nancy and Stephen Grand Technion Energy Program (GTEP).

  9. Nonorthogonality analysis of a thermoacoustic system with a premixed V-shaped flame

    International Nuclear Information System (INIS)

    Ji, Chenzhen; Zhao, Dan; Li, Xinyan; Li, Shihuai; Li, Junwei

    2014-01-01

    Highlights: • Nonorthogonality analysis of a choked thermoacoustic system is conducted. • A thermoacoustic model of a premixed V-shaped flame is developed. • Nonorthogonality is identified to arise from the boundary condition and the flame. • The contribution from the flame is shown to play a dominant role. • Eigenmodes nonorthogonality leads to transient growth of acoustic disturbances. - Abstract: Thermoacoustic instability occurs in many combustion systems, such as aero-engine afterburners, rocket motors, ramjets and gas turbines. It most often arises due to the coupling between unsteady heat release and acoustic waves. In this work, nonorthogonality analysis of a choked combustor with a gutter confined is conducted. Such configuration is used as a simplified model of the afterburner of an aero-engine. A thermoacoustic model is developed first to study the nonnormal interaction between acoustic disturbances and a premixed V-shaped flame anchored to the tip of the gutter. Eigenmode nonorthogonality analysis is then conducted. The thermoacoustic system is shown to be nonnormal and characterized by nonorthogonal eigenmodes. The nonorthogonality is identified to arise from both the complex boundary condition and the monopole-like flame. However, the contribution from the Robin-type boundary is approximately 1.5% of that from the flame. Thus the flame is identified to play a dominant role. One practical conclusions is that acoustic disturbances undergo transient growth in a combustion system with nonorthogonal eigenmodes. Such finite-time growth, which cannot be predicted by using classical linear theory might trigger high-amplitude self-sustained oscillations

  10. Determination of the stability limit of a thermoacoustic engine by means of finite elements

    NARCIS (Netherlands)

    de Jong, Anne; Wijnant, Ysbrand H.; de Boer, Andries

    2013-01-01

    A finite element model is presented to obtain the stability limit of, as an example, 2D standing wave thermoacoustic engine. The stability limit is the required heating to obtain self-sustained (thermo)acoustic oscillations. The method used to obtain the stability limit is not restricted to the

  11. Transmission characteristics of acoustic amplifier in thermoacoustic engine

    International Nuclear Information System (INIS)

    Sun Daming; Qiu Limin; Wang Bo; Xiao Yong

    2008-01-01

    Thermoacoustic engines are promising in practical applications for the merits of simple configuration, reliable operation and environmentally friendly working gas. An acoustic amplifier can increase the output pressure amplitude of a thermoacoustic engine (TE) and improve the matching between the engine and its load. In order to make full use of an acoustic amplifier, the transmission characteristics are studied based on linear thermoacoustic theory. Computational and experimental results show that the amplifying ability of an acoustic amplifier is mainly determined by its geometry parameters and output resistance impedance. The amplifying ability of an acoustic amplifier with appropriate length and diameter reaches its maximum when the output resistance impedance is infinite. It is also shown that the acoustic amplifier consumes an amount of acoustic power when amplifying pressure amplitude and the acoustic power consumption increases with amplifying ratio. Furthermore, a novel cascade acoustic amplifier is proposed, which has a much stronger amplifying ability with reduced acoustic power consumption. In experiments, a two-stage cascade acoustic amplifier amplifies the pressure ratio from 1.177 to 1.62 and produces a pressure amplitude of 0.547 MPa with nitrogen of 2.20 MPa as working gas. Good agreements are obtained between the theoretical analysis and experimental results. This research is instructive for comprehensively understanding the mechanism and making full use of the acoustic amplifier

  12. Thermo-Acoustic Convertor for Space Power, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In Phase Sunpower looked at Thermoacoustic Stirling Heat Engines (TASHEs). These ranged from a TASHE which was sized for the heat from a single General Purpose Heat...

  13. Numerical results on noise-induced dynamics in the subthreshold regime for thermoacoustic systems

    Science.gov (United States)

    Gupta, Vikrant; Saurabh, Aditya; Paschereit, Christian Oliver; Kabiraj, Lipika

    2017-03-01

    Thermoacoustic instability is a serious issue in practical combustion systems. Such systems are inherently noisy, and hence the influence of noise on the dynamics of thermoacoustic instability is an aspect of practical importance. The present work is motivated by a recent report on the experimental observation of coherence resonance, or noise-induced coherence with a resonance-like dependence on the noise intensity as the system approaches the stability margin, for a prototypical premixed laminar flame combustor (Kabiraj et al., Phys. Rev. E, 4 (2015)). We numerically investigate representative thermoacoustic models for such noise-induced dynamics. Similar to the experiments, we study variation in system dynamics in response to variations in the noise intensity and in a critical control parameter as the systems approach their stability margins. The qualitative match identified between experimental results and observations in the representative models investigated here confirms that coherence resonance is a feature of thermoacoustic systems. We also extend the experimental results, which were limited to the case of subcritical Hopf bifurcation, to the case of supercritical Hopf bifurcation. We identify that the phenomenon has qualitative differences for the systems undergoing transition via subcritical and supercritical Hopf bifurcations. Two important practical implications are associated with the findings. Firstly, the increase in noise-induced coherence as the system approaches the onset of thermoacoustic instability can be considered as a precursor to the instability. Secondly, the dependence of noise-induced dynamics on the bifurcation type can be utilised to distinguish between subcritical and supercritical bifurcation prior to the onset of the instability.

  14. Experimental study of microwave-induced thermoacoustic imaging

    Science.gov (United States)

    Jacobs, Ryan T.

    Microwave-Induced Thermoacoustic Imaging (TAI) is a noninvasive hybrid modality which improves contrast by using thermoelastic wave generation induced by microwave absorption. Ultrasonography is widely used in medical practice as a low-cost alternative and supplement to magnetic resonance imaging (MRI). Although ultrasonography has relatively high image resolution (depending on the ultrasonic wavelength at diagnostic frequencies), it suffers from low image contrast of soft tissues. In this work samples are irradiated with sub-microsecond electromagnetic pulses inducing acoustic waves in the sample that are then detected with an unfocused transducer. The advantage of this hybrid modality is the ability to take advantage of the microwave absorption coefficients which provide high contrast in tissue samples. This in combination with the superior spatial resolution of ultrasound waves is important to providing a low-cost alternative to MRI and early breast cancer detection methods. This work describes the implementation of a thermoacoustic experiment using a 5 kW peak power microwave source.

  15. Numerical Simulation of Pressure Fluctuations in the Thermo-acoustic Transducer

    Directory of Open Access Journals (Sweden)

    D. A. Uglanov

    2015-01-01

    Full Text Available The article describes the features of numerical simulation of acoustic oscillation excitation in the resonators with a foam insert (regenerator to study the excitation of thermo-acoustic oscillations in the circuit of small-sized engine model on the pulse tube.The aim of this work is the numerical simulation of the emerging oscillations in thermoacoustic engine resonator at the standing wave. As a basis, the work takes a thermo-acoustic resonator model with the open end (without piston developed in DeltaEC software. The precalculated operation frequency of the given resonator model, as a quarter of the wave resonator, is ν = 560 Hz.The paper offers a simplified finite element resonator model and defines the harmonic law of the temperature distribution on regenerator. The time dependences of the speed and pressure amplitude for the open end of the resonator are given; the calculated value of the process operating frequency is approximately equal to the value of the frequency for a given length of the resonator. Key findings, as a result of study, are as follows:1. The paper shows a potential for using this ESI-CFD Advanced software to simulate the processes of thermal excitation of acoustic oscillations.2. Visualization of turbulent flow fluctuations in the regenerator zone extends the analysis capability of gas-dynamic processes.3. Difference between operating frequency of the process simulated by ESI-CFD Advanced and frequency value obtained by analytical methods is about 4%, which is evidence of the model applicability to study the acoustic parameters of thermo-acoustic transducers. Experimental results have proved these data.

  16. A family of inversion formulas in thermoacoustic tomography

    KAUST Repository

    Nguyen, Linh

    2009-01-01

    We present a family of closed form inversion formulas in thermoacoustic tomography in the case of a constant sound speed. The formulas are presented in both time-domain and frequency-domain versions. As special cases, they imply most

  17. The Influence of the Density of Coconut Fiber as Stack in Thermo-Acoustics Refrigeration System

    Science.gov (United States)

    Hartulistiyoso, E.; Yulianto, M.; Sucahyo, L.

    2018-05-01

    An experimental study of using coconut fiber as stack with varying density in thermo-acoustics refrigeration system has been done. Stack is a device which is described as the “heart” in thermo-acoustics refrigeration system. The length of stack is a fix parameter in this experiment. The performance of the coconut fiber was evaluated from the density of stack (varied from 30%, 50% and 70%), position of stack (varied from 0 to 34 cm from the sound generator), and frequency of sound generator (varied from 150 Hz, 200Hz, 250Hz and 300Hz). The inside, outside, and environment temperatures were collected every second using Data Acquisition (DAQ). The result showed that the increase of stack density will increase the performance of thermo-acoustics refrigeration system. The higher density produced temperature differences in cold side and hot side of 5.4°C. In addition, the position of stack and frequency of sound generator have an important role in the performance of thermo-acoustics refrigeration system for all variations of the density.

  18. Thermoacoustic design using stem of goose down stack

    Science.gov (United States)

    Farikhah, Irna; Ristanto, Sigit; Idrus, Hadiyati; Kaltsum, Ummi; Faisal, Affandi; Setiawan, Ihsan; Setio Utomo, Agung Bambang

    2012-09-01

    Many refrigerators using CFC as a refrigerant are seen as the cause of the depletion of ozone. Hence, thermoacoustic was chosen as an alternative refrigerator that safe for environment. There are many variable that influenced the optimization of thermoacoustic design. One of them is thermal conductivity of material of stack. The Stack material must have a low thermal conductivity. In this research we used organic stack made of stem of goose down. It has superior thermal insulating. It means that they have the lowest thermal conductivity. The system uses no refrigerant or compressor, and the only mechanical moving part is the loudspeaker connected to a signal generator that produces the acoustic. The working fluid is air and the material of resonator is stainless steel. A series test on the laboratory found that there is a decrease of 5°C in temperature for about 2 minutes.

  19. Design and dynamic behaviour of a cold storage system combined with a solar powered thermoacoustic refrigerator

    International Nuclear Information System (INIS)

    Perier-Muzet, Maxime; Bedecarrats, Jean-Pierre; Stouffs, Pascal; Castaing-Lasvignottes, Jean

    2014-01-01

    A heat powered thermoacoustic refrigerator consists in a thermoacoustic engine that produces acoustic work utilizing heat, coupled to a thermoacoustic cooler that converts this acoustic energy into cooling effect. These machines have already proved their capability in laboratory or in space refrigeration. Previous studies have also demonstrated the possibility of using concentrated solar energy as thermal energy sources for low power heat driven thermoacoustic refrigerators. As other solar refrigeration systems, even if the cooling demand generally increases with the intensity of the solar radiation, one of the major difficulties is to insure a frigorific power supply when there is no, or low, solar radiation. The aim of this work is to study a kW scale solar thermoacoustic refrigerator capable to reach temperatures of the industrial refrigeration domain. This refrigerator is combined with a latent cold storage in order to guarantee a sufficient cooling capacity to face to refrigeration loads in spite of the production fluctuations. A description of the studied prototype is done and the model developed to describe the transient behaviour of the main components of this machine is introduced. The results obtained with a simulation of one week with real solar radiations are presented and the behaviour and the energetic performances of the entire system are analysed. Finally the impact of the sizing of the cold storage system is discussed. With the best storage design, the system is capable to supply a cooling power of 400 W at a temperature equal or lower than −20 °C with an average Coefficient Of Performance of the solar thermoacoustic refrigerator equal to 21%

  20. Thermoacoustic refrigerators and engines comprising cascading stirling thermodynamic units

    Science.gov (United States)

    Backhaus, Scott; Swift, Greg

    2013-06-25

    The present invention includes a thermoacoustic assembly and method for improved efficiency. The assembly has a first stage Stirling thermal unit comprising a main ambient heat exchanger, a regenerator and at least one additional heat exchanger. The first stage Stirling thermal unit is serially coupled to a first end of a quarter wavelength long coupling tube. A second stage Stirling thermal unit comprising a main ambient heat exchanger, a regenerator, and at least one additional heat exchanger, is serially coupled to a second end of the quarter wavelength long coupling tube.

  1. Computational Investigation on the performance of thermo-acoustically driven pulse tube refrigerator

    Science.gov (United States)

    Skaria, Mathew; Rasheed, K. K. Abdul; Shafi, K. A.; Kasthurirengan, S.; Behera, Upendra

    2017-02-01

    A Thermoacoustic Pulse Tube Refrigeration (TAPTR) system employs a thermo acoustic engine as the pressure wave generator instead of mechanical compressor. Such refrigeration systems are highly reliable due to the absence of moving components, structural simplicity and the use of environmental friendly working fluids. In the present work, a traveling wave thermoacoustic primmover (TWTAPM) has been developed and it is coupled to a pulse tube cryocooler. The performance of TAPTR depends on the operating and working fluid parameters. Simulation studies of the system has been performed using ANSYS Fluent and compared with experimental results.

  2. Towards numerical simulation of components of thermoacoustic devices with commercial CFD software: implementation of impedance boundary conditions and application to four different studies

    NARCIS (Netherlands)

    Bühler, Simon

    2015-01-01

    Thermoacoustic engines promise to be a cost effective and reliable alternative to traditional Stirling engines, as the function of the piston is fulfilled by an acoustic wave. For the design and development of thermoacoustic devices, the one-dimensional thermoacoustic equations are commonly used.

  3. Nontrivial influence of acoustic streaming on the efficiency of annular thermoacoustic prime movers

    International Nuclear Information System (INIS)

    Penelet, G.; Gusev, V.; Lotton, P.; Bruneau, M.

    2006-01-01

    The nonlinear processes controlling the time-dependent evolution of sound in annular thermoacoustic prime movers are studied. It is demonstrated that, under some heating conditions, the evolution of the temperature field induced by the excitation of acoustic streaming provides an additional amplification of sound which results in a complicated periodic onset and damping of thermoacoustic instability. The study of this particular example provides the opportunity to demonstrate that the excitation of acoustic streaming does not necessarily imply a decrease in the engine's efficiency

  4. Heat driven thermoacoustic cooler based on traveling-standing wave

    International Nuclear Information System (INIS)

    Kang Huifang; Zhou Gang; Li Qing

    2010-01-01

    This paper presents a heat driven thermoacoustic cooler system without any moving part. It consists of a thermoacoustic engine and a thermoacoustic cooler, and the former is the driving source of the latter. Both the engine and the cooler are located in one loop tube coupled with a resonator tube, and the acoustic power produced by the engine is used to drive the cooler directly. Both regenerators of the engine and the cooler are located in the near region of the pressure antinode, and operate in traveling-standing wave phase region. In the engine's regenerator, both components of the standing wave and the traveling wave realize the conversion from heat to acoustic energy. This improves the efficiency of the engine. In the cooler's regenerator, both components of the traveling wave and the standing wave pump heat from the cold end. This improves the efficiency of the cooler. At the operating point with a mean pressure of 22 bar, helium as working gas, a frequency of 234 Hz, and a heating power of 300 W, the experimental cooler provides a no-load temperature of -30 deg. C and a cooling power of 40 W at the cooling temperature of 0 deg. C. The total length of this cooler system is less than 1 m, which shows a good prospect for the domestic cooler system in room-temperature cooling such as food refrigeration and air-conditioning.

  5. Thermoacoustic sensor for nuclear fuel temperaturemonitoring and heat transfer enhancement

    Energy Technology Data Exchange (ETDEWEB)

    James A. Smith; Dale K. Kotter; Randall A. Alli; Steven L. Garrett

    2013-05-01

    A new acoustical sensing system for the nuclear power industry has been developed at The Pennsylvania State University in collaboration with Idaho National Laboratories. This sensor uses the high temperatures of nuclear fuel to convert a nuclear fuel rod into a standing-wave thermoacoustic engine. When a standing wave is generated, the sound wave within the fuel rod will be propagated, by acoustic radiation, through the cooling fluid within the reactor or spent fuel pool and can be monitored a remote location external to the reactor. The frequency of the sound can be correlated to an effective temperature of either the fuel or the surrounding coolant. We will present results for a thermoacoustic resonator built into a Nitonic-60 (stainless steel) fuel rod that requires only one passive component and no heat exchangers.

  6. Design, construction, and measurement of a large solar powered thermoacoustic cooler

    Science.gov (United States)

    Chen, Reh-Lin

    2001-07-01

    A device based on harnessing concentrated solar power in combination with using thermoacoustic principles has been built, instrumented, and tested. Its acoustic power is generated by solar radiation and is subsequently used to pump heat from external loads. The direct conversion between thermal and mechanical energy without going through any electronic stage makes the mechanism simple. Construction of the solar collector is also rather unsophisticated. It was converted from a 10-ft satellite dish with aluminized Mylar glued on the surface. The thermoacoustic device was mounted on the dish with its engine's hot side positioned near the focus of the parabolic dish, about 1 meter above the center of the dish. A 2-dimensional solar tracking system was built, using two servo motors to position the dish at pre-calculated coordinates. The solar powered thermoacoustic cooler is intended to be used where solar power is abundant and electricity may not be available or reliable. The cooler provides cooling during solar availability. Cooling can be maintained by the latent heat of ice when solar power is unattainable. The device has achieved cooling although compromised by gas leakage and thermal losses and was not able to provide temperatures low enough to freeze water. Improvements of the device are expected through modifications suggested herein.

  7. A thermoacoustic-Stirling heat engine: detailed study

    Science.gov (United States)

    Backhaus; Swift

    2000-06-01

    A new type of thermoacoustic engine based on traveling waves and ideally reversible heat transfer is described. Measurements and analysis of its performance are presented. This new engine outperforms previous thermoacoustic engines, which are based on standing waves and intrinsically irreversible heat transfer, by more than 50%. At its most efficient operating point, it delivers 710 W of acoustic power to its resonator with a thermal efficiency of 0.30, corresponding to 41% of the Carnot efficiency. At its most powerful operating point, it delivers 890 W to its resonator with a thermal efficiency of 0.22. The efficiency of this engine can be degraded by two types of acoustic streaming. These are suppressed by appropriate tapering of crucial surfaces in the engine and by using additional nonlinearity to induce an opposing time-averaged pressure difference. Data are presented which show the nearly complete elimination of the streaming convective heat loads. Analysis of these and other irreversibilities show which components of the engine require further research to achieve higher efficiency. Additionally, these data show that the dynamics and acoustic power flows are well understood, but the details of the streaming suppression and associated heat convection are only qualitatively understood.

  8. A family of inversion formulas in thermoacoustic tomography

    KAUST Repository

    Nguyen, Linh

    2009-10-01

    We present a family of closed form inversion formulas in thermoacoustic tomography in the case of a constant sound speed. The formulas are presented in both time-domain and frequency-domain versions. As special cases, they imply most of the previously known filtered backprojection type formulas. © 2009 AMERICAN INSTITUTE OF MATHEMATICAL SCIENCES.

  9. Friction Factor Correlation for Regenerator Working in a Travelling-Wave Thermoacoustic System

    Directory of Open Access Journals (Sweden)

    Fatimah A. Z. Mohd Saat

    2017-03-01

    Full Text Available Regenerator is a porous solid structure which is important in the travelling-wave thermoacoustic system. It provides the necessary contact surface and thermal capacity for the working gas to undergo a thermodynamic cycle under acoustic oscillatory flow conditions. However, it also creates a pressure drop that could degrade the overall system performance. Ideally, in a travelling-wave system, the phase angle between oscillating pressure and velocity in the regenerator should be zero, or as close to zero as possible. In this study, the hydrodynamic condition of a regenerator has been investigated both experimentally (in a purpose-built rig providing a travelling-wave phasing and numerically. A two-dimensional ANSYS FLUENT CFD model, capturing the important features of the experimental conditions, has been developed. The findings suggest that a steady-state correlation, commonly used in designing thermoacoustic systems, is applicable provided that the travelling-wave phase angle is maintained. However, for coarse mesh regenerators, the results show interesting “phase shifting” phenomena, which may limit the correlation validity. Current experimental and CFD studies are important for predicting the viscous losses in future models of thermoacoustic systems.

  10. Mathematics of Photoacoustic and Thermoacoustic Tomography

    KAUST Repository

    Kuchment, Peter; Kunyansky, Leonid

    2011-01-01

    The chapter surveys the mathematical models, problems, and algorithms of the thermoacoustic tomography (TAT) and photoacoustic tomography (PAT). TAT and PAT represent probably the most developed of the several novel “hybrid” methods of medical imaging. These new modalities combine different physical types of waves (electromagnetic and acoustic in case of TAT and PAT) in such a way that the resolution and contrast of the resulting method are much higher than those achievable using only acoustic or electromagnetic measurements.

  11. Thermodynamic measurement and analysis of dual-temperature thermoacoustic oscillations for energy harvesting application

    International Nuclear Information System (INIS)

    Zhao, Dan; Ji, Chenzhen; Li, Shihuai; Li, Junwei

    2014-01-01

    The present work considers energy harvesting by implementing both thermo- and piezo-electric power generation modules on a bifurcating tube, which produces dual-temperature thermoacoustic oscillations. The present system distinguished from the conventional standing-wave one does not involve heat exchangers and uses two different energy conversion processes to produce electricity. To measure and analyze the sound waves generated, an infrared thermal imaging camera, hot wire anemometry, and two arrays of K-type thermocouples and microphones are employed. It is found that the total electric power is approximately 5.71 mW, of which the piezo module produces about 0.21 mW. It is about 61% more than that generated by a similar conduction-driven thermo-acoustic-piezo harvester. In order to gain insight on the heat-driven acoustic oscillations and to simulate the experiment, thermodynamic laws are used to develop a nonlinear thermoacoustic model. Comparison is then made between the numerical and experimental results. Good agreement is obtained in terms of frequency and sound pressure level. Finally, Rayleigh index is examined to characterize the conversion between thermal and sound energy. In addition, energy redistribution between different thermoacoustic modes is estimated. It is found that lower frequency thermoacoustic oscillations are easier to trigger. - Highlights: • Energy harvesting from thermo- and piezo-electric diaphragms is obtained. • Total electrical power is approximately 5.71 mW. • Thermodynamic analysis of heat-driven oscillations is performed. • Rayleigh index characterizing heat-to-sound conversion is estimated. • Energy redistribution between various eigenmodes is calculated

  12. Output characteristics of Stirling thermoacoustic engine

    International Nuclear Information System (INIS)

    Sun Daming; Qiu Limin; Wang Bo; Xiao Yong; Zhao Liang

    2008-01-01

    A thermoacoustic engine (TE), which converts thermal energy into acoustic power by the thermoacoustic effect, shows several advantages due to the absence of moving parts, such as high reliability and long lifetime associated with reduced manufacturing costs. Power output and efficiency are important criteria of the performance of a TE. In order to increase the acoustic power output and thermal efficiency of a Stirling TE, the acoustic power distribution in the engine is studied with the variable load method. It is found that the thermal efficiency is independent of the output locations along the engine under the same acoustic power output. Furthermore, when the pressure ratio is kept constant at one location along the TE, it is beneficial to increasing the thermal efficiency by exporting more acoustic power. With nitrogen of 2.5 MPa as working gas and the pressure ratio at the compliance of 1.20 in the experiments, the acoustic power is measured at the compliance and the resonator simultaneously. The maximum power output, thermal efficiency and exergy efficiency reach 390.0 W, 11.2% and 16.0%, which are increased by 51.4%, 24.4% and 19.4%, respectively, compared to those with a single R-C load with 750 ml reservoir at the compliance. This research will be instructive for increasing the efficiency and making full use of the acoustic energy of a TE

  13. One-dimensional acoustic modeling of thermoacoustic instabilities (on cd)

    NARCIS (Netherlands)

    van Kampen, J.F.; Huls, R.A.; Kok, Jacobus B.W.; van der Meer, Theodorus H.; Nilsson, A.; Boden, H.

    2003-01-01

    In this paper the acoustic stability of a premixed turbulent natural gas flame confined in a combustor is investigated. Specifically when the flame is operated in a lean premixed mode, the thermoacoustic system is known to exhibit instabilities. These arise from a feedback mechanism between the

  14. Characterization and detection of thermoacoustic combustion oscillations based on statistical complexity and complex-network theory

    Science.gov (United States)

    Murayama, Shogo; Kinugawa, Hikaru; Tokuda, Isao T.; Gotoda, Hiroshi

    2018-02-01

    We present an experimental study on the characterization of dynamic behavior of flow velocity field during thermoacoustic combustion oscillations in a turbulent confined combustor from the viewpoints of statistical complexity and complex-network theory, involving detection of a precursor of thermoacoustic combustion oscillations. The multiscale complexity-entropy causality plane clearly shows the possible presence of two dynamics, noisy periodic oscillations and noisy chaos, in the shear layer regions (1) between the outer recirculation region in the dump plate and a recirculation flow in the wake of the centerbody and (2) between the outer recirculation region in the dump plate and a vortex breakdown bubble away from the centerbody. The vertex strength in the turbulence network and the community structure of the vorticity field can identify the vortical interactions during thermoacoustic combustion oscillations. Sequential horizontal visibility graph motifs are useful for capturing a precursor of themoacoustic combustion oscillations.

  15. Open cycle thermoacoustics

    Energy Technology Data Exchange (ETDEWEB)

    Reid, Robert Stowers [Georgia Inst. of Technology, Atlanta, GA (United States)

    2000-01-01

    A new type of thermodynamic device combining a thermodynamic cycle with the externally applied steady flow of an open thermodynamic process is discussed and experimentally demonstrated. The gas flowing through this device can be heated or cooled in a series of semi-open cyclic steps. The combination of open and cyclic flows makes possible the elimination of some or all of the heat exchangers (with their associated irreversibility). Heat is directly exchanged with the process fluid as it flows through the device when operating as a refrigerator, producing a staging effect that tends to increase First Law thermodynamic efficiency. An open-flow thermoacoustic refrigerator was built to demonstrate this concept. Several approaches are presented that describe the physical characteristics of this device. Tests have been conducted on this refrigerator with good agreement with a proposed theory.

  16. Numerical investigation of a looped-tube travelling-wave thermoacoustic engine with a bypass pipe

    International Nuclear Information System (INIS)

    Al-Kayiem, Ali; Yu, Zhibin

    2016-01-01

    A new configuration (“a looped-tube with a bypass pipe”) was recently proposed for low temperature travelling wave thermoacoustic engines and a prototype using atmospheric air as the working gas achieved an onset temperature difference as low as 65 °C. However, no further research has been reported about this new configuration to reveal its advantages and disadvantages. This paper aims to analyse this type of engine through a comprehensive numerical research. An engine of this type having dimensions similar to the reported prototype was firstly modelled. The calculated results were then qualitatively compared with the reported experimental data, showing a good agreement. The working principle of the engine was demonstrated and analysed. The research results show that an engine with such a bypass configuration essentially operates on the same thermodynamic principle as other travelling wave thermoacoustic engines, differing only in the design of the acoustic resonator. Both extremely short regenerators and a near-travelling wave resonator minimise the engine's acoustic losses, and thus significantly reduce its onset temperature difference. However, such short regenerators likely cause severe heat conduction losses, especially if the engine is applied to heat sources with higher temperatures. Furthermore, the acoustic power flowing back to the engine core is relatively low, while a large stream of acoustic power has to propagate within its resonator to maintain an acoustic resonance, potentially leading to low power density. The model was then applied to design an engine with a much longer regenerator and higher mean pressure to increase its power density. A thermoacoustic cooler was also added to the engine to utilise its acoustic power, allowing the evaluation of thermal efficiency. The pros and cons of the engine configuration are then discussed. - Highlights: • Analysed the working principle of a bypass type thermoacoustic engine. • Analysed the pros and

  17. A thermoacoustic-Stirling heat engine: Detailed study

    International Nuclear Information System (INIS)

    Backhaus, S.; Swift, G. W.

    2000-01-01

    A new type of thermoacoustic engine based on traveling waves and ideally reversible heat transfer is described. Measurements and analysis of its performance are presented. This new engine outperforms previous thermoacoustic engines, which are based on standing waves and intrinsically irreversible heat transfer, by more than 50%. At its most efficient operating point, it delivers 710 W of acoustic power to its resonator with a thermal efficiency of 0.30, corresponding to 41% of the Carnot efficiency. At its most powerful operating point, it delivers 890 W to its resonator with a thermal efficiency of 0.22. The efficiency of this engine can be degraded by two types of acoustic streaming. These are suppressed by appropriate tapering of crucial surfaces in the engine and by using additional nonlinearity to induce an opposing time-averaged pressure difference. Data are presented which show the nearly complete elimination of the streaming convective heat loads. Analysis of these and other irreversibilities show which components of the engine require further research to achieve higher efficiency. Additionally, these data show that the dynamics and acoustic power flows are well understood, but the details of the streaming suppression and associated heat convection are only qualitatively understood. (c) 2000 Acoustical Society of America

  18. Fission-powered in-core thermoacoustic sensor

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, Steven L. [Graduate Program in Acoustics, Penn State University, University Park, Pennsylvania 16802 (United States); Smith, James A. [Fundamental Fuel Properties, Idaho National Laboratory, Idaho Falls, Idaho 83415 (United States); Smith, Robert W. M. [Applied Research Laboratory, Penn State University, State College, Pennsylvania 16804 (United States); Heidrich, Brenden J. [Nuclear Science User Facilities, Idaho National Laboratory, Idaho Falls, Idaho 83415 (United States); Heibel, Michael D. [Global Technology Development, Westinghouse Electric Company, Cranberry Township, Pennsylvania 16066 (United States)

    2016-04-04

    A thermoacoustic engine is operated within the core of a nuclear reactor to acoustically telemeter coolant temperature (frequency-encoded) and reactor power level (amplitude-encoded) outside the reactor, thus providing the values of these important parameters without external electrical power or wiring. We present data from two hydrophones in the coolant (far from the core) and an accelerometer attached to a structure outside the reactor. These signals have been detected even in the presence of substantial background noise generated by the reactor's fluid pumps.

  19. Thermo-acoustic coupling in can-annular combustors : A numerical investigation

    NARCIS (Netherlands)

    Farisco, Federica; Panek, Lukasz; Kok, Jim B.W.; Pent, Jared; Rajaram, Rajesh

    2015-01-01

    Thermo-acoustic instabilities in modern, high power density gas turbines need to be predicted and understood in order to avoid unexpected damage and engine failure. While the annular combustor design is expected to suffer from the occurrence of transverse waves and burner-to-burner acoustic

  20. Orthogonal experimental study on high frequency cascade thermoacoustic engine

    International Nuclear Information System (INIS)

    Hu Zhongjun; Li Qing; Li Zhengyu; Li Qiang

    2008-01-01

    Orthogonal experiment design and variance analysis were adopted to investigate a miniature cascade thermoacoustic engine, which consisted of one standing wave stage and one traveling wave stage in series, operating at about 470 Hz, using helium as the working gas. Optimum matching of the heater powers between stages was very important for the performance of a cascade thermoacoustic engine, which was obtained from the orthogonal experiments. The orthogonal experiment design considered three experimental factors, i.e. the charging pressure and the heater powers in the two stages, which varied on five different levels, respectively. According to the range analysis and variance analysis from the orthogonal experiments, the charging pressure was the most sensitive factor influencing the dynamic pressure amplitude and onset temperature. The total efficiency and the dynamic pressure amplitude increased when the traveling wave stage heater power increased. The optimum ratio of the heater powers between the traveling wave stage and the standing wave stage was about 1.25, compromising the total efficiency with the dynamic pressure amplitude

  1. TH-AB-209-09: Quantitative Imaging of Electrical Conductivity by VHF-Induced Thermoacoustics

    Energy Technology Data Exchange (ETDEWEB)

    Patch, S; Hull, D [Avero Diagnostics, Irving, TX (United States); See, W [Medical College of Wisconsin, Milwaukee, WI (United States); Hanson, G [UW-Milwaukee, Milwaukee, WI (United States)

    2016-06-15

    Purpose: To demonstrate that very high frequency (VHF) induced thermoacoustics has the potential to provide quantitative images of electrical conductivity in Siemens/meter, much as shear wave elastography provides tissue stiffness in kPa. Quantitatively imaging a large organ requires exciting thermoacoustic pulses throughout the volume and broadband detection of those pulses because tomographic image reconstruction preserves frequency content. Applying the half-wavelength limit to a 200-micron inclusion inside a 7.5 cm diameter organ requires measurement sensitivity to frequencies ranging from 4 MHz down to 10 kHz, respectively. VHF irradiation provides superior depth penetration over near infrared used in photoacoustics. Additionally, VHF signal production is proportional to electrical conductivity, and prostate cancer is known to suppress electrical conductivity of prostatic fluid. Methods: A dual-transducer system utilizing a P4-1 array connected to a Verasonics V1 system augmented by a lower frequency focused single element transducer was developed. Simultaneous acquisition of VHF-induced thermoacoustic pulses by both transducers enabled comparison of transducer performance. Data from the clinical array generated a stack of 96-images with separation of 0.3 mm, whereas the single element transducer imaged only in a single plane. In-plane resolution and quantitative accuracy were measured at isocenter. Results: The array provided volumetric imaging capability with superior resolution whereas the single element transducer provided superior quantitative accuracy. Combining axial images from both transducers preserved resolution of the P4-1 array and improved image contrast. Neither transducer was sensitive to frequencies below 50 kHz, resulting in a DC offset and low-frequency shading over fields of view exceeding 15 mm. Fresh human prostates were imaged ex vivo and volumetric reconstructions reveal structures rarely seen in diagnostic images. Conclusion

  2. Experimental study on a co-axial pulse tube cryocooler driven by a small thermoacoustic stirling engine

    Science.gov (United States)

    Chen, M.; Ju, L. Y.; Hao, H. X.

    2014-01-01

    Small scale thermoacoustic heat engines have advantages in fields like space exploration and domestic applications considering small space occupation and ease of transport. In the present paper, the influence of resonator diameter on the general performance of a small thermoacoustic Stirling engine was experimentally investigated using helium as the working gas. Reducing the diameter of the resonator appropriately is beneficial for lower onset heating temperature, lower frequency and higher pressure amplitude. Based on the pressure distribution in the small thermoacoustic engine, an outlet for the acoustic work transmission was made to combine the engine and a miniature co-axial pulse tube cooler. The cooling performance of the whole refrigeration system without any moving part was tested. Experimental results showed that further efforts are required to optimize the engine performance and its match with the co-axial pulse tube cooler in order to obtain better cooling performance, compared with its original operating condition, driven by a traditional electrical linear compressor.

  3. Radiation-induced thermoacoustic imaging

    International Nuclear Information System (INIS)

    Bowen, T.

    1984-01-01

    This invention provides a new technique for obtaining information non-invasively on the composition and structures of a material or body by detecting radiation-induced thermoacoustic image features. This is accomplished by utilizing the acoustic wave generated by sudden thermal stress. The sudden thermal stress is induced by a pulse of radiation which deposits energy causing a rapid, but very small, rise of temperature (typically, ΔT approximately 10sup(-6) - 10sup(-5) deg C). The radiation may be ionizing radiation, such as high energy electrons, photons (x-rays), neutrons, or other charged particles or it may be non-ionizing radiation, such as R.F. and microwave electromagnetic radiation and ultrasonic radiation. The choice of radiation depends on the nature of the body to be imaged and the type of information desired

  4. Thermoacoustic and thermoreflectance imaging of biased integrated circuits: Voltage and temperature maps

    Energy Technology Data Exchange (ETDEWEB)

    Hernández-Rosales, E.; Cedeño, E. [Gleb Wataghin Physics Institute, University of Campinas - Unicamp, 13083-859 Campinas, SP (Brazil); Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Legaria 694, Colonia Irrigación, CP 11500, México, DF (Mexico); Hernandez-Wong, J. [Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Legaria 694, Colonia Irrigación, CP 11500, México, DF (Mexico); CONACYT, México, DF, México (Mexico); Rojas-Trigos, J. B.; Marin, E. [Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Legaria 694, Colonia Irrigación, CP 11500, México, DF (Mexico); Gandra, F. C. G.; Mansanares, A. M., E-mail: manoel@ifi.unicamp.br [Gleb Wataghin Physics Institute, University of Campinas - Unicamp, 13083-859 Campinas, SP (Brazil)

    2016-07-25

    In this work a combined thermoacoustic and thermoreflectance set-up was designed for imaging biased microelectronic circuits. In particular, it was used with polycrystalline silicon resistive tracks grown on a monocrystalline Si substrate mounted on a test chip. Thermoreflectance images, obtained by scanning a probe laser beam on the sample surface, clearly show the regions periodically heated by Joule effect, which are associated to the electric current distribution in the circuit. The thermoacoustic signal, detected by a pyroelectric/piezoelectric sensor beneath the chip, also discloses the Joule contribution of the whole sample. However, additional information emerges when a non-modulated laser beam is focused on the sample surface in a raster scan mode allowing imaging of the sample. The distribution of this supplementary signal is related to the voltage distribution along the circuit.

  5. Oscillatory flows in jet pumps: towards design guidelines for thermoacoustic applications

    NARCIS (Netherlands)

    Oosterhuis, Joris

    2016-01-01

    Thermoacoustic engines are an interesting alternative to conventional heat engines (such as Stirling engines) due to the absence of moving parts in the hot region and the small temperature difference required to operate. These engines can provide a durable solution in, for example, waste heat

  6. Thermo-acoustic cross-talk between cans in a can-annular combustor

    NARCIS (Netherlands)

    Farisco, Federica; Panek, Lukasz; Kok, Jim B.W.

    2017-01-01

    Thermo-acoustic instabilities in gas turbine engines are studied to avoid engine failure. Compared to the engines with annular combustors, the can-annular combustor design should be less vulnerable to acoustic burner-to-burner interaction, since the burners are acoustically coupled only by the

  7. Effect of temperature on thermoacoustic properties of olive oil in alcohol mixtures

    International Nuclear Information System (INIS)

    Shriwas, R S; Chimankar, O P; Tabhane, P V; Dange, S P; Tembhurkar, Y D

    2012-01-01

    The ultrasonic studies in liquids are great use in understanding the nature and strength of molecular interactions. Recently ultrasonic is the rapidly growing field research, which has been used in the food industry for both analysis and modification of food products. This paper presents ultrasonic velocity, density, adiabatic compressibility in olive oil with alcohol at different concentration that has been measured in the temperature range from 283.15K to 298.15K. The Moelwyn-Hughes parameter has been utilised to establish some simple relations between the available volumes, Bayer's non- linearity parameter, internal pressure, van der Waal's constant, Debye temperature etc. a relationship among the isobaric, isothermal and isochoric thermo-acoustical parameter have been studied and analyzed in the case olive oil with alcohol mixture. The present treatments had the distinct advantages of the thermo-acoustic parameters in the particular mixture.

  8. Thermoacoustic focusing lens by symmetric Airy beams with phase manipulations

    Science.gov (United States)

    Liu, Chen; Xia, Jian-Ping; Sun, Hong-Xiang; Yuan, Shou-Qi

    2017-12-01

    We report the realization of broadband acoustic focusing lenses based on two symmetric thermoacoustic phased arrays of Airy beams, in which the units of thermoacoustic phase control are designed by employing air with different temperatures surrounded by rigid insulated boundaries and thermal insulation films. The phase delays of the transmitted and reflected units could cover a whole 2π interval, which arises from the change of the sound velocity of air induced by the variation of the temperature. Based on the units of phase control, we design the transmitted and reflected acoustic focusing lenses with two symmetric Airy beams, and verify the high self-healing focusing characteristic and the feasibility of the thermal insulation films. Besides, the influences of the bending angle of the Airy beam on the focusing performance are discussed in detail. The proposed acoustic lens has advantages of broad bandwidth (about 4.8 kHz), high focusing performance, self-healing feature, and simple structure, which enable it to provide more schemes for acoustic focusing. It has excellent potential applications in acoustic devices.

  9. Thermoacoustic model of a modified free piston Stirling engine with a thermal buffer tube

    International Nuclear Information System (INIS)

    Yang, Qin; Luo, Ercang; Dai, Wei; Yu, Guoyao

    2012-01-01

    This article presents a modified free-piston Stirling heat engine configuration in which a thermal buffer tube is added to sandwich between the hot and cold heat exchangers. Such a modified configuration may lead to an easier fabrication and lighter weight of a free piston. To analyze the thermodynamic performance of the modified free piston Stirling heat engine, thermoacoustic theory is used. In the thermoacoustic modelling, the regenerator, the free piston, and the thermal buffer tube are given at first. Then, based on linear thermoacoustic network theory, the thermal and thermodynamic networks are presented to characterize acoustic pressure and volume flow rate distributions at different interfaces, and the global performance such as the power output, the heat input and the thermal efficiency. A free piston Stirling heat engine with several hundreds of watts mechanical power output is selected as an example. The typical operating and structure parameters are as follows: frequency around 50 Hz, mean pressure around 3.0 MPa, and a diameter of free piston around 50 mm. From the analysis, it was found that the modified free-piston Stirling heat engine has almost the same thermodynamic performance as the original design, which indicates that the modified configuration is worthy to develop in future because of its mechanical simplicity and reliability.

  10. Experimental Investigation of Bifurcations in a Thermoacoustic Engine

    OpenAIRE

    Vishnu R. Unni; Yogesh M. S. Prasaad; N. T. Ravi; S. Md Iqbal; Bala Pesala; R. I. Sujith

    2015-01-01

    In this study, variation in the characteristics of the pressure oscillations in a thermoacoustic engine is explored as the input heat flux is varied. A bifurcation diagram is plotted to study the variation in the qualitative behavior of the acoustic oscillations as the input heat flux changes. At a critical input heat flux (60 Watt), the engine begins to produce acoustic oscillations in its fundamental longitudinal mode. As the input heat flux is increased, incommensurate frequencies appear i...

  11. Measurement of Heat Flow Transmitted through a Stacked-Screen Regenerator of Thermoacoustic Engine

    Directory of Open Access Journals (Sweden)

    Shu Han Hsu

    2017-03-01

    Full Text Available A stacked-screen regenerator is a key component in a thermoacoustic Stirling engine. Therefore, the choice of suitable mesh screens is important in the engine design. To verify the applicability of four empirical equations used in the field of thermoacoustic engines and Stirling engines, this report describes the measurements of heat flow rates transmitted through the stacked screen regenerator inserted in an experimental setup filled with pressurized Argon gas having mean pressure of 0.45 MPa. Results show that the empirical equations reproduce the measured heat flow rates to a mutually similar degree, although their derivation processes differ. Additionally, results suggest that two effective pore radii would be necessary to account for the viscous and thermal behaviors of the gas oscillating in the stacked-screen regenerators.

  12. Basic treatment of onset conditions and transient effects in thermoacoustic Stirling engines

    NARCIS (Netherlands)

    Waele, de A.T.A.M.

    2009-01-01

    This paper treats the basics of thermoacoustic engines. The set of differential equations, which describes the dynamics of the individual components, is condensed in a single high-order differential equation which determines the time dependence of all dynamic variables. From this relation analytical

  13. Flame Interactions and Thermoacoustics in Multiple-Nozzle Combustors

    Science.gov (United States)

    Dolan, Brian

    The first major chapter of original research (Chapter 3) examines thermoacoustic oscillations in a low-emission staged multiple-nozzle lean direct injection (MLDI) combustor. This experimental program investigated a relatively practical combustor sector that was designed and built as part of a commercial development program. The research questions are both practical, such as under what conditions the combustor can be safely operated, and fundamental, including what is most significant to driving the combustion oscillations in this system. A comprehensive survey of operating conditions finds that the low-emission (and low-stability) intermediate and outer stages are necessary to drive significant thermoacoustics. Phase-averaged and time-resolved OH* imaging show that dramatic periodic strengthening and weakening of the reaction zone downstream of the low-emission combustion stages. An acoustic modal analysis shows the pressure wave shapes and identifies the dominant thermoacoustic behavior as the first longitudinal mode for this combustor geometry. Finally, a discussion of the likely significant coupling mechanisms is given. Periodic reaction zone behavior in the low-emission fuel stages is the primary contributor to unsteady heat release. Differences between the fuel stages in the air swirler design, the fuel number of the injectors, the lean blowout point, and the nominal operating conditions all likely contribute to the limit cycle behavior of the low-emission stages. Chapter 4 investigates the effects of interaction between two adjacent swirl-stabilized nozzles using experimental and numerical tools. These studies are more fundamental; while the nozzle hardware is the same as the lean direct injection nozzles used in the MLDI combustion concept, the findings are generally applicable to other swirl-stabilized combustion systems as well. Much of the work utilizes a new experiment where the distance between nozzles was varied to change the level of interaction

  14. Turbulent Flow Modification With Thermoacoustic Waves for Separation Control

    Science.gov (United States)

    2017-08-24

    respectively. At the outlet, the time-average flow is set to be the target state of the sponge zone. In this section, the effects of momentum thickness...Turbulent Flow Modification With Thermoacoustic Waves For Separation Control The views, opinions and/or findings contained in this report are those...currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. Florida State University Sponsored Research Administration 874

  15. The impact of stack geometry and mean pressure on cold end temperature of stack in thermoacoustic refrigeration systems

    Science.gov (United States)

    Wantha, Channarong

    2018-02-01

    This paper reports on the experimental and simulation studies of the influence of stack geometries and different mean pressures on the cold end temperature of the stack in the thermoacoustic refrigeration system. The stack geometry was tested, including spiral stack, circular pore stack and pin array stack. The results of this study show that the mean pressure of the gas in the system has a significant impact on the cold end temperature of the stack. The mean pressure of the gas in the system corresponds to thermal penetration depth, which results in a better cold end temperature of the stack. The results also show that the cold end temperature of the pin array stack decreases more than that of the spiral stack and circular pore stack geometry by approximately 63% and 70%, respectively. In addition, the thermal area and viscous area of the stack are analyzed to explain the results of such temperatures of thermoacoustic stacks.

  16. Sustainable New Brick and Thermo-Acoustic Insulation Panel from Mineralization of Stranded Driftwood Residues

    Directory of Open Access Journals (Sweden)

    Anna Laura Pisello

    2016-08-01

    Full Text Available There is considerable interest recently in by-products for application in green buildings. These materials are widely used as building envelope insulators or blocks. In this study, an experimental study was conducted to test stranded driftwood residues as raw material for possible thermo-acoustic insulation panel and environmentally sustainable brick. The thermal and acoustic characteristics of such a natural by-product were examined. Part of samples were mineralized by means of cement-based additive to reinforce the material and enhance its durability as well as fire resistance. Several mixtures with different sizes of ground wood chips and different quantities of cement were investigated. The thermo-acoustic in-lab characterization was aimed at investigating the thermal conductivity, thermal diffusivity, volumetric specific heat, and acoustic transmission loss. All samples were tested before and after mineralization. Results from this study indicate that it is possible to use stranded driftwood residues as building materials with competitive thermo-acoustic properties. In fact, the thermal conductivity was shown to be always around 0.07 W/mK in the unbound samples, and around double that value for the mineralized samples, which present a much higher volumetric specific heat (1.6 MJ/m3K and transmission loss capability. The lignin powder showed a sort of intermediate behavior between the unbound and the mineralized samples.

  17. Thermodynamic analysis of onset characteristics in a miniature thermoacoustic Stirling engine

    Science.gov (United States)

    Huang, Xin; Zhou, Gang; Li, Qing

    2013-06-01

    This paper analyzes the onset characteristics of a miniature thermoacoustic Stirling heat engine using the thermodynamic analysis method. The governing equations of components are reduced from the basic thermodynamic relations and the linear thermoacoustic theory. By solving the governing equation group numerically, the oscillation frequencies and onset temperatures are obtained. The dependences of the kinds of working gas, the length of resonator tube, the diameter of resonator tube, on the oscillation frequency are calculated. Meanwhile, the influences of hydraulic radius and mean pressure on the onset temperature for different working gas are also presented. The calculation results indicate that there exists an optimal dimensionless hydraulic radius to obtain the lowest onset temperature, whose value lies in the range of 0.30-0.35 for different working gases. Furthermore, the amplitude and phase relationship of pressures and volume flows are analyzed in the time-domain. Some experiments have been performed to validate the calculations. The calculation results agree well with the experimental values. Finally, an error analysis is made, giving the reasons that cause the errors of theoretical calculations.

  18. Exogenous contrast agents for thermoacoustic imaging: An investigation into the underlying sources of contrast

    International Nuclear Information System (INIS)

    Ogunlade, Olumide; Beard, Paul

    2015-01-01

    Purpose: Thermoacoustic imaging at microwave excitation frequencies is limited by the low differential contrast exhibited by high water content tissues. To overcome this, exogenous thermoacoustic contrast agents based on gadolinium compounds, iron oxide, and single wall carbon nanotubes have previously been suggested and investigated. However, these previous studies did not fully characterize the electric, magnetic, and thermodynamic properties of these agents thus precluding identification of the underlying sources of contrast. To address this, measurements of the complex permittivity, complex permeability, DC conductivity, and Grüneisen parameter have been made. These measurements allowed the origins of the contrast provided by each substance to be identified. Methods: The electric and magnetic properties of the contrast agents were characterized at 3 GHz using two rectangular waveguide cavities. The DC conductivity was measured separately using a conductivity meter. Thermoacoustic signals were then acquired and compared to those generated in water. Finally, 3D electromagnetic simulations were used to decouple the different contributions to the absorbed power density. Results: It was found that the gadolinium compounds provided appreciable electric contrast but not originating from the gadolinium itself. The contrast was either due to dissociation of the gadolinium salt which increased ionic conductivity or its nondissociated polar fraction which increased dielectric polarization loss or a combination of both. In addition, very high concentrations were required to achieve appreciable contrast, to the extent that the Grüneisen parameter increased significantly and became a source of contrast. Iron oxide particles were found to produce low but measurable dielectric contrast due to dielectric polarization loss, but this is attributed to the coating of the particles not the iron oxide. Single wall carbon nanotubes did not provide measurable contrast of any type

  19. Exogenous contrast agents for thermoacoustic imaging: An investigation into the underlying sources of contrast

    Energy Technology Data Exchange (ETDEWEB)

    Ogunlade, Olumide, E-mail: o.ogunlade@ucl.ac.uk; Beard, Paul [Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT (United Kingdom)

    2015-01-15

    Purpose: Thermoacoustic imaging at microwave excitation frequencies is limited by the low differential contrast exhibited by high water content tissues. To overcome this, exogenous thermoacoustic contrast agents based on gadolinium compounds, iron oxide, and single wall carbon nanotubes have previously been suggested and investigated. However, these previous studies did not fully characterize the electric, magnetic, and thermodynamic properties of these agents thus precluding identification of the underlying sources of contrast. To address this, measurements of the complex permittivity, complex permeability, DC conductivity, and Grüneisen parameter have been made. These measurements allowed the origins of the contrast provided by each substance to be identified. Methods: The electric and magnetic properties of the contrast agents were characterized at 3 GHz using two rectangular waveguide cavities. The DC conductivity was measured separately using a conductivity meter. Thermoacoustic signals were then acquired and compared to those generated in water. Finally, 3D electromagnetic simulations were used to decouple the different contributions to the absorbed power density. Results: It was found that the gadolinium compounds provided appreciable electric contrast but not originating from the gadolinium itself. The contrast was either due to dissociation of the gadolinium salt which increased ionic conductivity or its nondissociated polar fraction which increased dielectric polarization loss or a combination of both. In addition, very high concentrations were required to achieve appreciable contrast, to the extent that the Grüneisen parameter increased significantly and became a source of contrast. Iron oxide particles were found to produce low but measurable dielectric contrast due to dielectric polarization loss, but this is attributed to the coating of the particles not the iron oxide. Single wall carbon nanotubes did not provide measurable contrast of any type

  20. Detectability prediction for a thermoacoustic sensor in the breazeale nuclear reactor pool

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James [Idaho National Laboratory, Idaho Falls, ID (United States); Hrisko, Joshua [Idaho National Laboratory, Idaho Falls, ID (United States); Garrett, Steven [Idaho National Laboratory, Idaho Falls, ID (United States)

    2016-03-01

    Laboratory experiments have suggested that thermoacoustic engines can be in- corporated within nuclear fuel rods. Such engines would radiate sounds that could be used to measure and acoustically-telemeter information about the op- eration of the nuclear reactor (e.g., coolant temperature or uxes of neutrons or other energetic particles) or the physical condition of the nuclear fuel itself (e.g., changes in temperature, evolved gases) that are encoded as the frequency and/or amplitude of the radiated sound [IEEE Measurement and Instrumen- tation 16(3), 18-25 (2013)]. For such acoustic information to be detectable, it is important to characterize the vibroacoustical environments within reactors. Measurements will be presented of the background noise spectra (with and with- out coolant pumps) and reverberation times within the 70,000 gallon pool that cools and shields the fuel in the 1 MW research reactor on Penn State's campus using two hydrophones, a piezoelectric projector, and an accelerometer. Sev- eral signal-processing techniques will be demonstrated to enhance the measured results. Background vibrational measurement were also taken at the 250 MW Advanced Test Reactor, located at the Idaho National Laboratory, using ac- celerometers mounted outside the reactor's pressure vessel and on plumbing will also be presented. The detectability predictions made in the thesis were validated in September 2015 using a nuclear ssion-heated thermoacoustic sensor that was placed in the core of the Breazeale Nuclear Reactor on Penn State's campus. Some features of the thermoacoustic device used in that experiment will also be revealed. [Work supported by the U.S. Department of Energy.

  1. Holographic-interferometric and thermoanemometric study of a thermoacoustic prime mover

    Czech Academy of Sciences Publication Activity Database

    Trávníček, Zdeněk; Wang, A. B.; Lédl, Vít; Vít, Tomáš; Chen, Y. Ch.; Maršík, František

    2013-01-01

    Roč. 29, č. 1 (2013), s. 59-66 ISSN 1727-7191 R&D Projects: GA ČR(CZ) GCP101/11/J019 Institutional research plan: CEZ:AV0Z20760514 Institutional support: RVO:61388998 ; RVO:61389021 Keywords : thermoacoustics * holographic interferometry * hot-wire anemometry Subject RIV: BJ - Thermodynamics; BJ - Thermodynamics (UFP-V) Impact factor: 0.314, year: 2013 http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=8832965

  2. Investigation of a high frequency pulse tube cryocooler driven by a standing wave thermoacoustic engine

    International Nuclear Information System (INIS)

    Boroujerdi, A.A.; Ziabasharhagh, M.

    2014-01-01

    Highlights: • A nonlinear numerical model of a high frequency TADPTC has been developed. • The finite volume method has been used for discretization of governing equations. • The self-excitation process has been simulated very well. • The effects of APAT on the performance of the device have been investigated. • Lagrangian approach has been used to trace the thermodynamic cycle of gas parcels. - Abstract: In this work, a typical thermoacoustically driven pulse tube cooler as a no-moving part device has been investigated by a numerical method. A standing wave thermoacoustic engine as a prime mover in coupled with an inertance tube pulse tube cryocooler has been modeled. Nonlinear equations of unsteady one-dimensional compressible flow have been solved by the finite volume method. The model presents an important step towards the development of nonlinear simulation tools for the high amplitude thermoacoustic systems that are needed for practical use. The results of the computations show that the self-excited oscillations are well accompanied by the increasing of the pressure amplitude. The necessity of implementation of a nonlinear model to investigate such devices has been proven. The effect of APAT length as an amplifier coupler on the performance of the cooler has been investigated. Furthermore, by using Lagrangian approach, thermodynamic cycle of gas parcels has been attained

  3. Critical Temperature Differences of a Standing Wave Thermoacoustic Prime Mover with Various Helium-Based Binary Mixture Working Gases

    Science.gov (United States)

    Setiawan, Ikhsan; Nohtomi, Makoto; Katsuta, Masafumi

    2015-06-01

    Thermoacoustic prime movers are energy conversion devices which convert thermal energy into acoustic work. The devices are environmentally friendly because they do not produce any exhaust gases. In addition, they can utilize clean energy such as solar-thermal energy or waste heat from internal combustion engines as the heat sources. The output mechanical work of thermoacoustic prime movers are usually used to drive a thermoacoustic refrigerator or to generate electricity. A thermoacoustic prime mover with low critical temperature difference is desired when we intend to utilize low quality of heat sources such as waste heat and sun light. The critical temperature difference can be significantly influenced by the kinds of working gases inside the resonator and stack's channels of the device. Generally, helium gas is preferred as the working gas due to its high sound speed which together with high mean pressure will yield high acoustic power per unit volume of the device. Moreover, adding a small amount of a heavy gas to helium gas may improve the efficiency of thermoacoustic devices. This paper presents numerical study and estimation of the critical temperature differences of a standing wave thermoacoustic prime mover with various helium-based binary-mixture working gases. It is found that mixing helium (He) gas with other common gases, namely argon (Ar), nitrogen (N2), oxygen (O2), and carbon dioxide (CO2), at appropriate pressures and molar compositions, reduce the critical temperature differences to lower than those of the individual components of the gas mixtures. In addition, the optimum mole fractions of Hegas which give the minimum critical temperature differences are shifted to larger values as the pressure increases, and tends to be constant at around 0.7 when the pressure increases more than 2 MPa. However, the minimum critical temperature differences slightly increase as the pressure increases to higher than 1.5 MPa. Furthermore, we found that the lowest

  4. In vivo microwave-based thermoacoustic tomography of rats (Conference Presentation)

    Science.gov (United States)

    Lin, Li; Zhou, Yong; Wang, Lihong V.

    2016-03-01

    Microwave-based thermoacoustic tomography (TAT), based on the measurement of ultrasonic waves induced by microwave pulses, can reveal tissue dielectric properties that may be closely related to the physiological and pathological status of the tissues. Using microwaves as the excitation source improved imaging depth because of their deep penetration into biological tissues. We demonstrate, for the first time, in vivo microwave-based thermoacoustic imaging in rats. The transducer is rotated around the rat in a full circle, providing a full two-dimensional view. Instead of a flat ultrasonic transducer, we used a virtual line detector based on a cylindrically focused transducer. A 3 GHz microwave source with 0.6 µs pulse width and an electromagnetically shielded transducer with 2.25 MHz central frequency provided clear cross-sectional images of the rat's body. The high imaging contrast, based on the tissue's rate of absorption, and the ultrasonically defined spatial resolution combine to reveal the spine, kidney, muscle, and other deeply seated anatomical features in the rat's abdominal cavity. This non-invasive and non-ionizing imaging modality achieved an imaging depth beyond 6 cm in the rat's tissue. Cancer diagnosis based on information about tissue properties from microwave band TAT can potentially be more accurate than has previously been achievable.

  5. Numerical Predictions of Early Stage Turbulence in Oscillatory Flow across Parallel-Plate Heat Exchangers of a Thermoacoustic System

    Directory of Open Access Journals (Sweden)

    Fatimah A. Z. Mohd Saat

    2017-06-01

    Full Text Available This work focuses on the predictions of turbulent transition in oscillatory flow subjected to temperature gradients, which often occurs within heat exchangers of thermoacoustic devices. A two-dimensional computational fluid dynamics (CFD model was developed in ANSYS FLUENT and validated using the earlier experimental data. Four drive ratios (defined as maximum pressure amplitude to mean pressure were investigated: 0.30%, 0.45%, 0.65% and 0.83%. It has been found that the introduction of the turbulence model at a drive ratio as low as 0.45% improves the predictions of flow structure compared to experiments, which indicates that turbulent transition may occur at much smaller flow amplitudes than previously thought. In the current investigation, the critical Reynolds number based on the thickness of Stokes’ layer falls in the range between 70 and 100. The models tested included four variants of the RANS (Reynolds-Averaged Navier–Stokes equations: k-ε, k-ω, shear-stress-transport (SST-k-ω and transition-SST, the laminar model being used as a reference. Discussions are based on velocity profiles, vorticity plots, viscous dissipation and the resulting heat transfer and their comparison with experimental results. The SST-k-ω turbulence model and, in some cases, transition-SST provide the best fit of the velocity profile between numerical and experimental data (the value of the introduced metric measuring the deviation of the CFD velocity profiles from experiment is up to 43% lower than for the laminar model and also give the best match in terms of calculated heat flux. The viscous dissipation also increases with an increase of the drive ratio. The results suggest that turbulence should be considered when designing thermoacoustic devices even in low-amplitude regimes in order to improve the performance predictions of thermoacoustic systems.

  6. Synthetical optimization of hydraulic radius and acoustic field for thermoacoustic cooler

    International Nuclear Information System (INIS)

    Kang Huifang; Li Qing; Zhou Gang

    2009-01-01

    It is well known that the acoustic field and the hydraulic radius of the regenerator play key roles in thermoacoustic processes. The optimization of hydraulic radius strongly depends on the acoustic field in the regenerator. This paper investigates the synthetical optimization of hydraulic radius and acoustic field which is characterized by the ratio of the traveling wave component to the standing wave component. In this paper, we discussed the heat flux, cooling power, temperature gradient and coefficient of performance of thermoacoustic cooler with different combinations of hydraulic radiuses and acoustic fields. The calculation results show that, in the cooler's regenerator, due to the acoustic wave, the heat is transferred towards the pressure antinodes in the pure standing wave, while the heat is transferred in the opposite direction of the wave propagation in the pure traveling wave. The better working condition for the regenerator appears in the traveling wave phase region of the like-standing wave, where the directions of the heat transfer by traveling wave component and standing wave component are the same. Otherwise, the small hydraulic radius is not a good choice for acoustic field with excessively high ratio of traveling wave, and the small hydraulic radius is only needed by the traveling wave phase region of like-standing wave.

  7. Development of thermoacoustic engine operating by waste heat from cooking stove

    Science.gov (United States)

    Chen, B. M.; Abakr, Y. A.; Riley, P. H.; Hann, D. B.

    2012-06-01

    There are about 1.5 billion people worldwide use biomass as their primary form of energy in household cooking[1]. They do not have access to electricity, and are too remote to benefit from grid electrical supply. In many rural communities, stoves are made without technical advancements, mostly using open fires cooking stoves which have been proven to be extremely low efficiency, and about 93% of the energy generated is lost during cooking. The cooking is done inside a dwelling and creates significant health hazard to the family members and pollution to environment. SCORE (www.score.uk.com) is an international collaboration research project to design and build a low-cost, high efficiency woodstove that uses about half amount of the wood of an open wood fire, and uses the waste heat of the stove to power a thermoacoustic engine (TAE) to produce electricity for applications such as LED lighting, charging mobile phones or charging a 12V battery. This paper reviews on the development of two types of the thermoacoustic engine powered by waste heat from cooking stove which is either using Propane gas or burning of wood as a cooking energy to produce an acceptable amount of electricity for the use of rural communities.

  8. Experimental evaluation of DC electric field effect on the thermoacoustic behaviour of flat premixed flames

    NARCIS (Netherlands)

    Volkov, E.N.; Kornilov, V.N.; Goey, de L.P.H.

    2013-01-01

    One promising approach to eliminate thermoacoustic instabilities in combustion appliances is the use of adaptive control of the flame/burner acoustic transfer function (TF). Application of a DC electric field (EF) as a spatially distributed, easily and quickly adjustable and low-energy method to

  9. Thermo-acoustic characterization of the burner-turbine interface in a can-annular combustor using CFD

    NARCIS (Netherlands)

    Farisco, Federica

    2016-01-01

    Thermo-acoustic instabilities in high power density gas turbine engines need to be understood to avoid unexpected shutdown events. This dissertation is focused on the combustor-turbine interaction for acoustic waves. The first part of the study is based on the acoustic reflection coefficient

  10. Thermoacoustic Molecular Imaging of Small Animals

    Directory of Open Access Journals (Sweden)

    Robert A. Kruger

    2003-04-01

    Full Text Available We have designed, constructed, and tested a thermoacoustic computed tomography (TCT scanner for imaging optical absorption in small animals in three dimensions. The device utilizes pulsed laser irradiation (680–1064 nm and a unique, 128-element transducer array. We quantified the isotropic spatial resolution of this scanner to be 0.35 mm. We describe a dual-wavelength subtraction technique for isolating optical dyes with TCT. Phantom experiments demonstrate that we can detect 5 fmol of a near-infrared dye (indocyanine green, ICG in a 1-ML volume using dual-wavelength subtraction. Initial TCT imaging in phantoms and in two sacrificed mice suggests that three-dimensional, optical absorption patterns in small animals can be detected with an order of magnitude better spatial resolution and an order of magnitude better low-contrast detectability in small animals when compared to fluorescence imaging or diffusion optical tomography.

  11. Thermoacoustic tomography for an integro-differential wave equation modeling attenuation

    Science.gov (United States)

    Acosta, Sebastián; Palacios, Benjamín

    2018-02-01

    In this article we study the inverse problem of thermoacoustic tomography (TAT) on a medium with attenuation represented by a time-convolution (or memory) term, and whose consideration is motivated by the modeling of ultrasound waves in heterogeneous tissue via fractional derivatives with spatially dependent parameters. Under the assumption of being able to measure data on the whole boundary, we prove uniqueness and stability, and propose a convergent reconstruction method for a class of smooth variable sound speeds. By a suitable modification of the time reversal technique, we obtain a Neumann series reconstruction formula.

  12. Adjoint-based sensitivity analysis of low-order thermoacoustic networks using a wave-based approach

    Science.gov (United States)

    Aguilar, José G.; Magri, Luca; Juniper, Matthew P.

    2017-07-01

    Strict pollutant emission regulations are pushing gas turbine manufacturers to develop devices that operate in lean conditions, with the downside that combustion instabilities are more likely to occur. Methods to predict and control unstable modes inside combustion chambers have been developed in the last decades but, in some cases, they are computationally expensive. Sensitivity analysis aided by adjoint methods provides valuable sensitivity information at a low computational cost. This paper introduces adjoint methods and their application in wave-based low order network models, which are used as industrial tools, to predict and control thermoacoustic oscillations. Two thermoacoustic models of interest are analyzed. First, in the zero Mach number limit, a nonlinear eigenvalue problem is derived, and continuous and discrete adjoint methods are used to obtain the sensitivities of the system to small modifications. Sensitivities to base-state modification and feedback devices are presented. Second, a more general case with non-zero Mach number, a moving flame front and choked outlet, is presented. The influence of the entropy waves on the computed sensitivities is shown.

  13. Thermoacoustic CT of the breast: pilot study observations

    Science.gov (United States)

    Kruger, Robert A.; Kiser, William L., Jr.; Romilly, A. P.; Scmidt, Phyllis

    2001-06-01

    In order to assess the potential clinical utility of using thermoacoustic computer tomography (TCT) to image the breast, we conducted a retrospective pilot study of 78 patients. We recruited patients in three age groups (50 years). The study population was further segregated into normal and suspicious based on the results of the previous x-ray mammography and ultrasound. Image quality was evaluated qualitatively by consensus of two trained mammographers using a 4-point scale. The appearance of normal anatomy, cysts, benign disease and cancer was noted. Patients were also asked to rate the comfort of the TCT exam and to indicate a personal preference for x-ray mammography or TCT. Analysis of the data indicated that TCT image quality was dependent upon both patient age and breast density, improving with both increasing breast density and decreasing patient age. Fibrocystic disease was well seen, cysts appearing as areas of low RF absorption. Fibroadenomas did not demonstrate contrast enhancement with the exception of one patient with associated atypical hyperplasia. Cancer displayed higher RF absorption than surrounding tissues in 4/7 patients in whom cancer was confirmed, including one patient with a 7-mm ductal carcinoma in situ (DCIS).

  14. Influence of thermodynamic properties of a thermo-acoustic emitter on the efficiency of thermal airborne ultrasound generation.

    Science.gov (United States)

    Daschewski, M; Kreutzbruck, M; Prager, J

    2015-12-01

    In this work we experimentally verify the theoretical prediction of the recently published Energy Density Fluctuation Model (EDF-model) of thermo-acoustic sound generation. Particularly, we investigate experimentally the influence of thermal inertia of an electrically conductive film on the efficiency of thermal airborne ultrasound generation predicted by the EDF-model. Unlike widely used theories, the EDF-model predicts that the thermal inertia of the electrically conductive film is a frequency-dependent parameter. Its influence grows non-linearly with the increase of excitation frequency and reduces the efficiency of the ultrasound generation. Thus, this parameter is the major limiting factor for the efficient thermal airborne ultrasound generation in the MHz-range. To verify this theoretical prediction experimentally, five thermo-acoustic emitter samples consisting of Indium-Tin-Oxide (ITO) coatings of different thicknesses (from 65 nm to 1.44 μm) on quartz glass substrates were tested for airborne ultrasound generation in a frequency range from 10 kHz to 800 kHz. For the measurement of thermally generated sound pressures a laser Doppler vibrometer combined with a 12 μm thin polyethylene foil was used as the sound pressure detector. All tested thermo-acoustic emitter samples showed a resonance-free frequency response in the entire tested frequency range. The thermal inertia of the heat producing film acts as a low-pass filter and reduces the generated sound pressure with the increasing excitation frequency and the ITO film thickness. The difference of generated sound pressure levels for samples with 65 nm and 1.44 μm thickness is in the order of about 6 dB at 50 kHz and of about 12 dB at 500 kHz. A comparison of sound pressure levels measured experimentally and those predicted by the EDF-model shows for all tested emitter samples a relative error of less than ±6%. Thus, experimental results confirm the prediction of the EDF-model and show that the model can

  15. Thermo-acoustic instabilities in lean premixed swirl-stabilized combustion and their link to acoustically coupled and decoupled flame macrostructures

    KAUST Repository

    Taamallah, Soufien; LaBry, Zachary A.; Shanbhogue, Santosh J.; Ghoniem, Ahmed F.

    2015-01-01

    © 2014 The Combustion Institute. Published by Elsevier Inc. All rights reserved. We investigate the onset of thermo-acoustic instabilities and their link to the mean flame configurations - or macrostructures - under acoustically coupled

  16. Correspondence Between Uncoupled Flame Macrostructures and Thermoacoustic Instability in Premixed Swirl-Stabilized Combustion

    KAUST Repository

    Taamallah, Soufien

    2014-06-16

    In this paper, we conduct an experimental investigation of a confined premixed swirl-stabilized dump combustor similar to those found in modern gas turbines. We operate the combustor with premixed methane-air in the lean range of equivalence ratio ϕ ∈ [0.5–0.75]. First, we observe different dynamic modes in the lean operating range, as the equivalence ratio is raised, confirming observations made previously in a similar combustor geometry but with a different fuel [1]. Next we examine the correspondence between dynamic mode transitions and changes in the mean flame configuration or macrostructure. We show that each dynamic mode is associated with a specific flame macrostructure. By modifying the combustor length without changing the underlying flow, the resonant frequencies of the geometry are altered allowing for decoupling the heat release fluctuations and the acoustic field, in a certain range of equivalence ratio. Mean flame configurations in the modified (short) combustor and for the same range of equivalence ratio are examined. It is found that not only the same sequence of flame configurations is observed in both combustors (long and short) but also that the set of equivalence ratio where transitions in the flame configuration occur is closely related to the onset of thermo-acoustic instabilities. For both combustor lengths, the flame structure changes at similar equivalence ratio whether thermo-acoustic coupling is allowed or not, suggesting that the flame configuration holds the key to understanding the onset of self-excited thermo-acoustic instability in this range. Finally, we focus on the flame configuration transition that was correlated with the onset of the first dynamically unstable mode ϕ ∈ [0.61–0.64]. Our analysis of this transition in the short, uncoupled combustor shows that it is associated with an intermittent appearance of a flame in the outer recirculation zone (ORZ). The spectral analysis of this “ORZ flame flickering”

  17. Correspondence Between Uncoupled Flame Macrostructures and Thermoacoustic Instability in Premixed Swirl-Stabilized Combustion

    KAUST Repository

    Taamallah, Soufien; LaBry, Zachary A.; Shanbhogue, Santosh J.; Ghoniem, Ahmed F.

    2014-01-01

    In this paper, we conduct an experimental investigation of a confined premixed swirl-stabilized dump combustor similar to those found in modern gas turbines. We operate the combustor with premixed methane-air in the lean range of equivalence ratio ϕ ∈ [0.5–0.75]. First, we observe different dynamic modes in the lean operating range, as the equivalence ratio is raised, confirming observations made previously in a similar combustor geometry but with a different fuel [1]. Next we examine the correspondence between dynamic mode transitions and changes in the mean flame configuration or macrostructure. We show that each dynamic mode is associated with a specific flame macrostructure. By modifying the combustor length without changing the underlying flow, the resonant frequencies of the geometry are altered allowing for decoupling the heat release fluctuations and the acoustic field, in a certain range of equivalence ratio. Mean flame configurations in the modified (short) combustor and for the same range of equivalence ratio are examined. It is found that not only the same sequence of flame configurations is observed in both combustors (long and short) but also that the set of equivalence ratio where transitions in the flame configuration occur is closely related to the onset of thermo-acoustic instabilities. For both combustor lengths, the flame structure changes at similar equivalence ratio whether thermo-acoustic coupling is allowed or not, suggesting that the flame configuration holds the key to understanding the onset of self-excited thermo-acoustic instability in this range. Finally, we focus on the flame configuration transition that was correlated with the onset of the first dynamically unstable mode ϕ ∈ [0.61–0.64]. Our analysis of this transition in the short, uncoupled combustor shows that it is associated with an intermittent appearance of a flame in the outer recirculation zone (ORZ). The spectral analysis of this “ORZ flame flickering”

  18. Identification of flame transfer functions in the presence of intrinsic thermoacoustic feedback and noise

    Science.gov (United States)

    Jaensch, Stefan; Merk, Malte; Emmert, Thomas; Polifke, Wolfgang

    2018-05-01

    The Large Eddy Simulation/System Identification (LES/SI) approach is a general and efficient numerical method for deducing a Flame Transfer Function (FTF) from the LES of turbulent reacting flow. The method may be summarised as follows: a simulated flame is forced with a broadband excitation signal. The resulting fluctuations of the reference velocity and of the global heat release rate are post-processed via SI techniques in order to estimate a low-order model of the flame dynamics. The FTF is readily deduced from the low-order model. The SI method most frequently applied in aero- and thermo-acoustics has been Wiener-Hopf Inversion (WHI). This method is known to yield biased estimates in situations with feedback, thus it was assumed that non-reflective boundary conditions are required to generate accurate results with the LES/SI approach. Recent research has shown that the FTF is part of the so-called Intrinsic ThermoAcoustic (ITA) feedback loop. Hence, identifying an FTF from a compressible LES is always a closed-loop problem, and consequently one should expect that the WHI would yield biased results. However, several studies proved that WHI results compare favourably with validation data. To resolve this apparent contradiction, a variety of identification methods are compared against each other, including models designed for closed-loop identification. In agreement with theory, we show that the estimate given by WHI does not converge to the actual FTF. Fortunately, the error made is small if excitation amplitudes can be set such that the signal-to-noise ratio is large, but not large enough to trigger nonlinear flame dynamics. Furthermore, we conclude that non-reflective boundary conditions are not essentially necessary to apply the LES/SI approach.

  19. Passive control of thermoacoustic instabilities in swirl-stabilized combustion at elevated pressures

    Directory of Open Access Journals (Sweden)

    L Justin Williams

    2016-09-01

    Full Text Available In this study, a porous insert is placed at the dump plane of a swirl-stabilized lean premixed combustor to passively suppress thermoacoustic instabilities. The diffuser-shaped annular ring of porous inert material influences the turbulent flow field directly, including recirculation zones and vortical and/or shear layer structures to passively control the acoustic performance of the combustor. The porous inert material is made of silicon carbide–hafnium carbide coated, high-strength, high-temperature-resistant open-cell foam materials. In this study, the porous insert concept is investigated at above-ambient operating pressures to demonstrate its suitability for practical combustion applications. Experiments are conducted in quartz and metal combustors, without and with the porous insert while varying operating pressure, equivalence ratio, and reactant flow rate. Measurements show that the porous insert, and consequent changes in the combustor flow field, decrease the sound pressure levels at the frequency of combustion instability at all operating conditions investigated in this study. The porous insert also decreases the broadband combustion noise, i.e. the measured sound pressure levels over a wide frequency range.

  20. Effect of Dynamic Pressure on the Performance of Thermoacoustic Refrigerator with Aluminium (Al) Resonator

    Science.gov (United States)

    Arya, Bheemsha; Nayak, B. Ramesh; Shivakumara, N. V.

    2018-04-01

    In practice the refrigerants are being used in the conventional refrigeration system to get the required cooling effect. These refrigerants produce Chlorofluorocarbons (CFCs) and Hydro chlorofluorocarbons (HCFCs) which are highly harmful to the environment, particularly depleting of ozone layers resulting in green house emissions. In order to overcome these effects, the research needs to be focused on the development of an ecofriendly refrigeration system. The thermoacoustic refrigeration system is one among such system where the sound waves are used to compress and expand the gas particles. This study focuses on the effect of dynamic pressure on the thermoacoustic refrigerator made of aluminium with overall length of 748.82 mm, and the entire inner surface of the resonator tube was coated with 2mm thickness of polyurethane to minimize the heat losses to the atmosphere. Experiments were conducted with different stack geometries i.e. parallel plates having 0.119 mm thick with spacing between the plates maintained at 0.358 mm, 1mm diameter pipes, 2mm diameter pipes and 4 mm diameter pipes. Experiments were also conducted with different drive ratios of 0.6%, 1% and 1.6% for a constant dynamic pressure of 2 bar and 10 bar for helium and air as working medium. The results were plotted with the help of graphs, the variation of coefficient of performance (COP) and the relative coefficient of performance (COPR) for the above said conditions were calculated.

  1. Thermoacoustic instability of a laminar premixed flame in Rijke tube with a hydrodynamic region

    Science.gov (United States)

    Zhao, Dan; Chow, Z. H.

    2013-07-01

    In this work, a Rijke tube with a hydrodynamic region confined is considered to investigate its non-normality and the effect of the hydrodynamic region on the system stability behaviors. Experiments are first conducted on Rijke tubes with different lengths. It is found that the fundamental mode frequency is decreased and then increased, as the flame is placed at different axial positions at the bottom half of the tube. This trend agrees well with the prediction from the thermoacoustic model developed, of which the hydrodynamic region is modelled as an oscillating 'airplug' and the flame dynamics is captured by using classical G-equation. In addition, the flame as measured is found to respond differently to oncoming acoustic disturbances. Modal and non-modal stability analyses are then conducted to determine the eigenmode growth rate and the transient one of acoustic disturbances. The 'safest' and most 'dangerous' flame locations as defined as those corresponding to extreme eigenmode and transient growth rate are estimated, and compared with those from the model without the hydrodynamic region. In order to mitigate such detrimental oscillations, identification and mitigation algorithms are experimentally implemented on the Rijke tube. The sound pressure level is reduced by approximately 50 dB. To gain insights on the thermoacoustic system, transfer function of the actuated Rijke tube system is measured by injecting a broad-band white noise. Compared with the estimation from our model, good agreement is observed. Finally, the marginal stability regions are estimated.

  2. Revisiting the difference between traveling-wave and standing-wave thermoacoustic engines - A simple analytical model for the standing-wave one

    Science.gov (United States)

    Yasui, Kyuichi; Kozuka, Teruyuki; Yasuoka, Masaki; Kato, Kazumi

    2015-11-01

    There are two major categories in a thermoacoustic prime-mover. One is the traveling-wave type and the other is the standing-wave type. A simple analytical model of a standing-wave thermoacoustic prime-mover is proposed at relatively low heat-flux for a stack much shorter than the acoustic wavelength, which approximately describes the Brayton cycle. Numerical simulations of Rott's equations have revealed that the work flow (acoustic power) increases by increasing of the amplitude of the particle velocity (| U|) for the traveling-wave type and by increasing cosΦ for the standing-wave type, where Φ is the phase difference between the particle velocity and the acoustic pressure. In other words, the standing-wave type is a phase-dominant type while the traveling-wave type is an amplitude-dominant one. The ratio of the absolute value of the traveling-wave component (| U|cosΦ) to that of the standing-wave component (| U|sinΦ) of any thermoacoustic engine roughly equals the ratio of the absolute value of the increasing rate of | U| to that of cosΦ. The different mechanism between the traveling-wave and the standing-wave type is discussed regarding the dependence of the energy efficiency on the acoustic impedance of a stack as well as that on ωτα, where ω is the angular frequency of an acoustic wave and τα is the thermal relaxation time. While the energy efficiency of the traveling-wave type at the optimal ωτα is much higher than that of the standing-wave type, the energy efficiency of the standing-wave type is higher than that of the traveling-wave type at much higher ωτα under a fixed temperature difference between the cold and the hot ends of the stack.

  3. Solar-driven refrigeration technologies; Koeltechnologieen op zonne-energie

    Energy Technology Data Exchange (ETDEWEB)

    De Cillis, S.; Infante Ferreira, C.A. [Technische Universiteit Delft, Delft (Netherlands); Krieg, J. [Unilever Foods and Health Research Institute, Vlaardingen (Netherlands)

    2005-12-01

    A review is presented of solar driven refrigeration technologies. A subdivision is made between electric driven and thermal driven systems. Their potential and stage of development are discussed. The electric driven systems include Stirling, thermo-acoustic, thermoelectric, electrochemical and membrane assisted absorption systems. The thermal driven systems include absorption and adsorption systems. A model is used to compare the performance of the different solutions. [Dutch] Dit artikel geeft een overzicht van zon-aangedreven koeltechnologieen. Er wordt onderscheid gemaakt tussen elektrisch en thermisch aangedreven systemen. Hun potentieel en niveau van ontwikkeling worden besproken. De elektrisch aangedreven systemen omvatten Stirling, thermo-akoestisch, thermo-elektrisch, elektrochemisch en membraanondersteund absorptiesystemen.De warmte-aangedreven systemen omvatten absorptie en adsorptie. Er wordt gebruik gemaakt van een model om de prestaties van de verschillende alternatieven onderling te vergelijken.

  4. Impact of acoustic impedance and flow resistance on the power output capacity of the regenerators in travelling-wave thermoacoustic engines

    International Nuclear Information System (INIS)

    Yu Zhibin; Jaworski, Artur J.

    2010-01-01

    This paper considers the role of acoustic impedance, flow resistance, configuration and geometrical dimensions of regenerators on the power produced in travelling-wave thermoacoustic engines. The effects are modelled assuming a pure travelling-wave and ideal gas, which allows defining a pair of dimensionless factors based on the 'net' acoustic power production. Based on the analysis provided, the acoustic power flow in the regenerators is investigated numerically. It is shown that impedance essentially reflects the proportion between the acoustic power produced from heat energy through the thermoacoustic processes and the acoustic power dissipated by viscous and thermal-relaxation effects in the regenerators. Viscous resistance of the regenerator mainly determines the magnitude of the volumetric velocity and then affects the magnitude of acoustic impedance. High impedance and high volumetric velocity are both required in the regenerators for high power engines. The results also show that the optimum transverse dimension of the gas passage exists, but depends on the local acoustic impedance. In principle, it is possible to obtain an optimum combination between these two parameters.

  5. Basic principles of thermo-acoustic energy and temporal profile detection of microwave pulses

    CERN Document Server

    Andreev, V G; Vdovin, V A

    2001-01-01

    Basic principles of a thermo-acoustic method developed for the detection of powerful microwave pulses of nanosecond duration are discussed.A proposed method is based on the registration of acoustic pulse profile originated from the thermal expansion of the volume where microwave energy was absorbed.The amplitude of excited acoustic transient is proportional to absorbed microwave energy and its temporal profile resembles one of a microwave pulse when certain conditions are satisfied.The optimal regimes of microwave pulse energy detection and sensitivity of acoustic transient registration with piezo-transducer are discussed.It was demonstrated that profile of a microwave pulse could be detected with temporal resolution of 1 - 3 nanosecond.

  6. Reproduction of mouse-pup ultrasonic vocalizations by nanocrystalline silicon thermoacoustic emitter

    Science.gov (United States)

    Kihara, Takashi; Harada, Toshihiro; Kato, Masahiro; Nakano, Kiyoshi; Murakami, Osamu; Kikusui, Takefumi; Koshida, Nobuyoshi

    2006-01-01

    As one of the functional properties of ultrasound generator based on efficient thermal transfer at the nanocrystalline silicon (nc-Si) layer surface, its potential as an ultrasonic simulator of vocalization signals is demonstrated by using the acoustic data of mouse-pup calls. The device composed of a surface-heating thin-film electrode, an nc-Si layer, and a single-crystalline silicon (c-Si) wafer, exhibits an almost completely flat frequency response over a wide range without any mechanical surface vibration systems. It is shown that the fabricated emitter can reproduce digitally recorded ultrasonic mouse-pups vocalizations very accurately in terms of the call duration, frequency dispersion, and sound pressure level. The thermoacoustic nc-Si device provides a powerful physical means for the understanding of ultrasonic communication mechanisms in various living animals.

  7. A thermoacoustic engine capable of utilizing multi-temperature heat sources

    International Nuclear Information System (INIS)

    Qiu Limin; Wang Bo; Sun Daming; Liu Yu; Steiner, Ted

    2009-01-01

    Low-grade energy is widespread. However, it cannot be utilized with high thermal efficiency directly. Following the principle of thermal energy cascade utilization, a thermoacoustic engine (TE) with a new regenerator that can be driven by multiple heat sources at different temperature levels is proposed. Taking a regenerator that utilizes heat sources at two temperatures as an example, theoretical research has been conducted on a traveling-wave TE with the new regenerator to predict its performance. Experimental verification is also done to demonstrate the benefits of the new regenerator. Results indicate that a TE with the new regenerator utilizing additional heat at a lower temperature experiences an increase in pressure ratio, acoustic power, efficiency, and exergy efficiency with proper heat input at an appropriate temperature at the mid-heater. A regenerator that uses multi-temperature heat sources can provide a means of recovering lower grade heat.

  8. Thermo-acoustic instabilities in lean premixed swirl-stabilized combustion and their link to acoustically coupled and decoupled flame macrostructures

    KAUST Repository

    Taamallah, Soufien

    2015-01-01

    © 2014 The Combustion Institute. Published by Elsevier Inc. All rights reserved. We investigate the onset of thermo-acoustic instabilities and their link to the mean flame configurations - or macrostructures - under acoustically coupled and decoupled conditions. Methane-hydrogen mixtures are used to explore the role of the fuel in changing the flame macrostructure, as determined by chemilumi-nescence, as the equivalence ratio (φ) varies. We observe four different configurations: a columnar flame (I); a bubble-columnar flame (II); a single conical flame (III); and a double conical flame (IV). We also observe different thermo-acoustic modes in the lean regime investigated, φ ∈ [0.5-0.75], that correspond to different flame configurations. By changing the combustor length without affecting the underlying flow, the resonant modes of the combustor are shifted to higher frequencies allowing for the decoupling of heat release fluctuations and the acoustic field over a range of equivalence ratio. We find that the same flame macrostructures observed in the long, acoustically coupled combustor arise in the short, acoustically decoupled combustor and transition at similar equivalence ratios in both combustors. The onset of the first fully unstable mode in the long combustor occurs at similar equivalence ratio as the flame transition from configuration III to IV. In the acoustically decoupled case, this transition occurs gradually starting with the intermittent appearance of a flame in the outer recirculation zone (ORZ). Spectral analysis of this phenomenon, referred to as "ORZ flame flickering" shows the existence of an unsteady event occurring over a narrow frequency band centered around 28 Hz along with a weaker broadband region at lower frequency in the range [1-10] Hz. The tone at 28 Hz is shown to be associated with the azimuthal advection of the flame by the outer recirculation zone flow. Changes in the fuel composition, by adding hydrogen (up to 20%), do not

  9. Broadband Spectroscopic Thermoacoustic Characterization of Single-Walled Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Daniel R. Bauer

    2015-01-01

    Full Text Available Carbon nanotubes have attracted interest as contrast agents for biomedical imaging because they strongly absorb electromagnetic radiation in the optical and microwave regions. This study applies thermoacoustic (TA imaging and spectroscopy to measure the frequency-dependent absorption profile of single-walled carbon nanotubes (SWNT in the ranges of 2.7–3.1 GHz and 7–9 GHz using two tunable microwave sources. Between 7 and 9 GHz, the peak TA signal for solutions containing semiconducting and metallic SWNTs increased monotonically with a slope of 1.75 AU/GHz (R2=0.95 and 2.8 AU/GHz (R2=0.93, respectively, relative to a water baseline. However, after compensating for the background signal from water, it was revealed that the TA signal from metallic SWNTs increased exponentially within this frequency band. Results suggest that TA imaging and spectroscopy could be a powerful tool for quantifying the absorption properties of SWNTs and optimizing their performance as contrast agents for imaging or heat sources for thermal therapy.

  10. Vortical flow structure of thermoacoustic oscillations in a closed tube

    International Nuclear Information System (INIS)

    Ishii, Katsuya; Kitagawa, Shyun; Ishigaki, Masahiro; Adachi, Shizuko

    2014-01-01

    Spontaneous thermoacoustic oscillations of a gas in a closed cylindrical tube are studied. Numerical simulations of the flow field in the tube on which a temperature gradient along the axis is imposed are performed by solving the axisymmetric compressible Navier–Stokes equations. The wall temperature of the hot part near both ends (300 K) and that of the cold part near the center (20 K) are fixed. The computations are done for various values of the length ratio ξ of the hot part to the cold part between 0.3 and 1.0, and steady oscillatory states are obtained. These states are divided into three groups according to the magnitude of the pressure amplitude. The state in each group has distinguished features of the flow field. We analyze the effect of vortices on the structure of the temperature distribution. The difference of the boundary layer thickness between the hot part and the cold part is shown to play an important role. (paper)

  11. Vortical flow structure of thermoacoustic oscillations in a closed tube

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Katsuya [Information Technology Center, Nagoya University, Furou-chou, Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Kitagawa, Shyun [Department of Computational Science and Engineering, Graduate School of Engineering, Nagoya University, Furou-chou, Chikusa-ku, Nagoya, Aichi 464-8603 (Japan); Ishigaki, Masahiro [Japan Atomic Energy Agency, 2–4 Shirakata-shirane, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Adachi, Shizuko, E-mail: ishii@cc.nagoya-u.ac.jp [School of Business and Commerce, Tokyo International University, Matoba-kita, Kawagoe-shi, Saitama 350-1197 (Japan)

    2014-12-01

    Spontaneous thermoacoustic oscillations of a gas in a closed cylindrical tube are studied. Numerical simulations of the flow field in the tube on which a temperature gradient along the axis is imposed are performed by solving the axisymmetric compressible Navier–Stokes equations. The wall temperature of the hot part near both ends (300 K) and that of the cold part near the center (20 K) are fixed. The computations are done for various values of the length ratio ξ of the hot part to the cold part between 0.3 and 1.0, and steady oscillatory states are obtained. These states are divided into three groups according to the magnitude of the pressure amplitude. The state in each group has distinguished features of the flow field. We analyze the effect of vortices on the structure of the temperature distribution. The difference of the boundary layer thickness between the hot part and the cold part is shown to play an important role. (paper)

  12. TU-FG-BRB-09: Thermoacoustic Range Verification with Perfect Co-Registered Overlay of Bragg Peak onto Ultrasound Image

    Energy Technology Data Exchange (ETDEWEB)

    Patch, S; Kireeff Covo, M; Jackson, A; Qadadha, Y; Campbell, K; Albright, R; Bloemhard, P; Donoghue, A; Siero, C; Gimpel, T; Small, S; Ninemire, B; Johnson, M; Phair, L [Lawrence Berkeley National Lab, Berkeley, CA (United States)

    2016-06-15

    Purpose: The potential of particle therapy has not yet been fully realized due to inaccuracies in range verification. The purpose of this work was to correlate the Bragg peak location with target structure, by overlaying thermoacoustic localization of the Bragg peak onto an ultrasound image. Methods: Pulsed delivery of 50 MeV protons was accomplished by a fast chopper installed between the ion source and the inflector of the 88″ cyclotron at Lawrence Berkeley National Lab. 2 Gy were delivered in 2 µs by a beam with peak current of 2 µA. Thermoacoustic emissions were detected by a cardiac array and Verasonics V1 ultrasound system, which also generated a grayscale ultrasound image. 1024 thermoacoustic pulses were averaged before filtering and one-way beamforming focused signal onto the Bragg peak location with perfect co-registration to the ultrasound images. Data was collected in a room temperature water bath and gelatin phantom with a cavity designed to mimic the intestine, in which gas pockets can displace the Bragg peak. Experiments were performed with the cavity both empty and filled with olive oil. Results: In the waterbath overlays of the Bragg peak agreed with Monte Carlo simulations to within 800±170 µm. Agreement within 1.3 ± 0.2 mm was achieved in the gelatin phantom, although relative stopping powers were estimated only to first order from CT scans. Protoacoustic signals were detected after travel from the Bragg peak through 29 mm and 65 mm of phantom material when the cavity was empty and full of olive oil, respectively. Conclusion: Protoacoustic range verification is feasible with a commercial clinical ultrasound array, but at doses exceeding the clinical realm. Further optimization of both transducer array and injection line chopper is required to enable range verification within a 2 Gy dose limit, which would enable online adaptive treatment. This work was supported in part by a UWM Intramural Instrumentation Grant and by the Director, Office

  13. Analysis of Thermo-Acoustic Emission from Damage in Composite Laminates under Thermal Cyclic Loading

    International Nuclear Information System (INIS)

    Kim, Young Bok; Min, Dae Hong; Lee, Deok Bo; Choi, Nak Sam

    2001-01-01

    An investigation on nondestructive evaluation of thermal stress-reduced damage in the composite laminates (3mm in thickness and [+45 6 /-45 6 ] S lay-up angles) has been performed using the thermo-acoustic emission technique. Reduction of thermo-AE events due to repetitive thermal load cycles showed a Kaiser effect. An analysis of the thermo-AE behavior determined the stress free temperature of composite laminates. Fiber fracture and matrix cracks were observed using the optical microscopy, scanning electron microscopy and ultrasonic C-sean. Short-Time Fourier Transform of thermo-AE signals offered the time-frequency characteristics which might classify the thermo-AE as three different types to estimate the damage processes of the composites

  14. Experimental and Numerical Investigation of Thermoacoustic Sources Related to High-Frequency Instabilities

    Directory of Open Access Journals (Sweden)

    Mathieu Zellhuber

    2014-03-01

    Full Text Available Flame dynamics related to high-frequency instabilities in gas turbine combustors are investigated using experimental observations and numerical simulations. Two different combustor types are studied, a premix swirl combustor (experiment and a generic reheat combustor (simulation. In both cases, a very similar dynamic behaviour of the reaction zone is observed, with the appearance of transverse displacement and coherent flame wrinkling. From these observations, a model for the thermoacoustic feedback linked to transverse modes is proposed. The model splits heat release rate fluctuations into distinct contributions that are related to flame displacement and variations of the mass burning rate. The decomposition procedure is applied on the numerical data and successfully verified by comparing a reconstructed Rayleigh index with the directly computed value. It thus allows to quantify the relative importance of various feedback mechanisms for a given setup.

  15. System Identification and Resonant Control of Thermoacoustic Engines for Robust Solar Power

    Directory of Open Access Journals (Sweden)

    Boe-Shong Hong

    2015-05-01

    Full Text Available It was found that thermoacoustic solar-power generators with resonant control are more powerful than passive ones. To continue the work, this paper focuses on the synthesis of robustly resonant controllers that guarantee single-mode resonance not only in steady states, but also in transient states when modelling uncertainties happen and working temperature temporally varies. Here the control synthesis is based on the loop shifting and the frequency-domain identification in advance thereof. Frequency-domain identification is performed to modify the mathematical modelling and to identify the most powerful mode, so that the DSP-based feedback controller can online pitch the engine to the most powerful resonant-frequency robustly and accurately. Moreover, this paper develops two control tools, the higher-order van-der-Pol oscillator and the principle of Dynamical Equilibrium, to assist in system identification and feedback synthesis, respectively.

  16. Experimental investigation on preconditioned rate induced tipping in a thermoacoustic system.

    Science.gov (United States)

    Tony, J; Subarna, S; Syamkumar, K S; Sudha, G; Akshay, S; Gopalakrishnan, E A; Surovyatkina, E; Sujith, R I

    2017-07-14

    Many systems found in nature are susceptible to tipping, where they can shift from one stable dynamical state to another. This shift in dynamics can be unfavorable in systems found in various fields ranging from ecology to finance. Hence, it is important to identify the factors that can lead to tipping in a physical system. Tipping can mainly be brought about by a change in parameter or due to the influence of external fluctuations. Further, the rate at which the parameter is varied also determines the final state that the system attains. Here, we show preconditioned rate induced tipping in experiments and in a theoretical model of a thermoacoustic system. We provide a specific initial condition (preconditioning) and vary the parameter at a rate higher than a critical rate to observe tipping. We find that the critical rate is a function of the initial condition. Our study is highly relevant because the parameters that dictate the asymptotic behavior of many physical systems are temporally dynamic.

  17. DEVELOPMENT AND ASSESSMENT OF A SCORE™ DEMO2.1 THERMO-ACOUSTIC ENGINE

    Directory of Open Access Journals (Sweden)

    BAIMAN CHEN

    2013-04-01

    Full Text Available The early low-cost, wood burning Thermo-Acoustic Engine (TAE known as Demo2.0-build-1 was developed by SCORE™ at the UK Centre and was capable of achieving 22.7 Watts of electricity. This prototype was limited to an operating temperature of about 300oC and due to excessive leaks could not operate continuously above ambient pressure. To absorb a thermal heat input of 4.4 kW from the burning wood so as to fulfil the required acoustic power, the Hot Heat Exchanger (HHX requires heating to the highest possible temperature. Therefore, a corrugated stainless steel plate HHX design that maximises heating surface area was adopted to the current Demo2 TAE design. In addition, the system is often pressurised to achieve higher acoustic intensity. Rigorous sealing of the system at high temperature is also required. A Demo2.1 TAE design based on the Demo2 TAE design and its prototype which is developed recently by the SCORE™ Centre in Malaysia was successfully constructed and well integrated with the stove. During the early construction and assembly process, fabrication difficulties and serious leak problems around the HHX’s edges were found when the apparatus operated at high temperatures. This is because the uneven geometrical HHX (convolution profile makes it difficult and relatively costly to be sealed. The Demo2.1 TAE is focused on the sealing efficiency and effective manufacturing cost by meantime to allow further modification variation. The design was made to adopt the local manufacturing technologies and materials available or easy to access in Malaysia. It also aims to minimise the parasitic heat losses to lower the system onset temperature. By removing the Linear Alternator and Tuning Volume from the system, preliminary measurements shown that the apparatus was oscillating at the frequency of 70 Hz. A much lower onset temperature was observed at around 144oC for the new configuration when the apparatus was oscillating at approximately 200 Pa

  18. Iterative reconstruction methods for Thermo-acoustic Tomography

    International Nuclear Information System (INIS)

    Marinesque, Sebastien

    2012-01-01

    We define, study and implement various iterative reconstruction methods for Thermo-acoustic Tomography (TAT): the Back and Forth Nudging (BFN), easy to implement and to use, a variational technique (VT) and the Back and Forth SEEK (BF-SEEK), more sophisticated, and a coupling method between Kalman filter (KF) and Time Reversal (TR). A unified formulation is explained for the sequential techniques aforementioned that defines a new class of inverse problem methods: the Back and Forth Filters (BFF). In addition to existence and uniqueness (particularly for backward solutions), we study many frameworks that ensure and characterize the convergence of the algorithms. Thus we give a general theoretical framework for which the BFN is a well-posed problem. Then, in application to TAT, existence and uniqueness of its solutions and geometrical convergence of the algorithm are proved, and an explicit convergence rate and a description of its numerical behaviour are given. Next, theoretical and numerical studies of more general and realistic framework are led, namely different objects, speeds (with or without trapping), various sensor configurations and samplings, attenuated equations or external sources. Then optimal control and best estimate tools are used to characterize the BFN convergence and converging feedbacks for BFF, under observability assumptions. Finally, we compare the most flexible and efficient current techniques (TR and an iterative variant) with our various BFF and the VT in several experiments. Thus, robust, with different possible complexities and flexible, the methods that we propose are very interesting reconstruction techniques, particularly in TAT and when observations are degraded. (author) [fr

  19. Thermoacoustic contrast of prostate cancer due to heating by very high frequency irradiation

    International Nuclear Information System (INIS)

    Patch, S K; Hull, D; Thomas, M; Jacobsohn, K; See, WA; Griep, SK

    2015-01-01

    Applying the thermoacoustic (TA) effect to diagnostic imaging was first proposed in the 1980s. The object under test is irradiated by high-power pulses of electromagnetic energy, which heat tissue and cause thermal expansion. Outgoing TA pressure pulses are detected by ultrasound transducers and reconstructed to provide images of the object. The TA contrast mechanism is strongly dependent upon the frequency of the irradiating electromagnetic pulse. When very high frequency (VHF) electromagnetic irradiation is utilized, TA signal production is driven by ionic content. Prostatic fluids contain high levels of ionic metabolites, including citrate, zinc, calcium, and magnesium. Healthy prostate glands produce more ionic metabolites than diseased glands. VHF pulses are therefore expected to generate stronger TA signal in healthy prostate glands than in diseased glands. A benchtop system for performing ex vivo TA computed tomography with VHF energy is described and images are presented. The system utilizes irradiation pulses of 700 ns duration exceeding 20 kW power. Reconstructions frequently visualize anatomic landmarks such as the urethra and verumontanum. TA reconstructions from three freshly excised human prostate glands with little, moderate, and severe cancerous involvement are compared with histology. TA signal strength is negatively correlated with percent cancerous involvement in this small sample size. For the 45 regions of interest analyzed, a reconstruction value of 0.4 mV provides 100% sensitivity but only 29% specificity. This sample size is far too small to draw sweeping conclusions, but the results warrant a larger volume study including comparison of TA images to the gold standard, histology. (paper)

  20. Thermoacoustic imaging of prostate cancer: comparison to histology

    Science.gov (United States)

    Patch, S. K.; Griep, S. K.; Jacobsohn, K.; See, W. A.; Hull, D.

    2014-03-01

    Ex vivo imaging of fresh prostate specimens was performed to test the hypothesis that the thermoacoustic (TA) contrast mechanism generated with very high frequency electromagnetic (EM) irradiation is sensitive to prostate cancer. Ex vivo imaging was performed immediately after radical prostatectomy, performed as part of normal care. Irradiation pulsewidth was 700 ns and duty cycle was extremely low. Typical specific absorption rate (SAR) throughout the prostate was 70-90 kW/kg during pulsing, but time-averaged SAR was below 2 W/kg. TA pressure pulses generated by rapid heating due to EM energy deposition were detected using single element transducers. 15g/L glycine powder mixed into DI water served as acoustic couplant, which was chilled to prevent autolysis. Spatial encoding was performed by scanning in tomographic "step-and-shoot" mode, with 3 mm translation between slices and 1.8-degree rotation between tomographic views. Histology slides for 3 cases scanned with 2.25 MHz transducers were marked for comparison to TA reconstructions. These three cases showed little, moderate, and severe involvement in the histology levels surrounding the verumontanum. TA signal strength decreased with percent cancerous involvement. When VHF is used for tissue heating, the TA contrast mechanism is driven by ionic content and we observed suppressed TA signal from diseased prostate tissue in the peripheral zone. For the 45 regions of interest analyzed, a reconstruction value of 0.4 mV provides 100% sensitivity but only 29% specificity.

  1. The Design, Construction, and Experimental Evaluation of a Compact Thermoacoustic-Stirling Engine Generator for Use in a micro-CHP Appliance

    Science.gov (United States)

    Wilcox, Douglas A., Jr.

    Micro combined heat and power or micro-CHP is the simultaneous generation of useful heat and electricity on a residential scale. The heat and electricity are produced at the point of use, avoiding the distribution losses associated with a centralized power plant. These appliances combine a conventional gas-fired condensing boiler with an electric power module capable of generating electricity from the heat of combustion. Currently, the leading power modules for micro-CHP appliances are free-piston Stirling engines (FPSEs) which can generate 1050 watts of electricity at a thermal-to-electric efficiency of 26%.[1] These external combustion engines have been under development for the last 25 years, with FPSE micro-CHP appliances only recently being introduced to the commercial market. Publications by developers assert unlimited service life and high efficiency, with low noise and emissions; but despite these claims, the actual reliability and cost of manufacturing has prevented their successful mass-market adoption. A Thermoacoustic-Stirling Engine Generator or TaSEG is one possible alternative to FPSE's. A TaSEG uses a thermoacoustic engine, or acoustic heat engine, which can efficiently convert high temperature heat into acoustic power while maintaining a simple design with fewer moving parts than traditional FPSE's. This simpler engine is coupled to an electrodynamic alternator capable of converting acoustic power into electricity. This thesis outlines the design, construction, and experimental evaluation of a TaSEG which is appropriate for integration with a gas burner inside of a residential micro- CHP appliance. The design methodology is discussed, focusing on how changes in the geometry affected the predicted performance. Details of its construction are given and the performance of the TaSEG is then outlined. The TaSEG can deliver 132 watts of electrical output power to an electric load with an overall measured thermal-to-electric (first law) efficiency of eta

  2. Experimental study of thermoacoustic effects on a single plate. Pt. 1. Temperature fields

    Energy Technology Data Exchange (ETDEWEB)

    Wetzel, M.; Herman, C. [Johns Hopkins Univ., Baltimore, MD (USA). Dept. of Mech. Eng.

    2000-03-01

    The thermal interaction between a heated solid plate and the acoustically driven working fluid was investigated by visualizing and quantifying the temperature fields in the neighbourhood of the solid plate. A combination of holographic interferometry and high-speed cinematography was applied in the measurements. A better knowledge of these temperature fields is essential to develop systematic design methodologies for heat exchangers in oscillatory flows. The difference between heat transfer in oscillatory flows with zero mean velocity and steady-state flows is demonstrated in the paper. Instead of heat transfer from a heated solid surface to the colder bulk fluid, the visualized temperature fields indicated that heat was transferred from the working fluid into the stack plate at the edge of the plate. In the experiments, the thermoacoustic effect was visualized through the temperature measurements. A novel evaluation procedure that accounts for the influence of the acoustic pressure variations on the refractive index was applied to accurately reconstruct the high-speed, two-dimensional oscillating temperature distributions. (orig.)

  3. In vivo tumor detection with combined MR–Photoacoustic-Thermoacoustic imaging

    Directory of Open Access Journals (Sweden)

    Lin Huang

    2016-09-01

    Full Text Available Here, we report a new method using combined magnetic resonance (MR–Photoacoustic (PA–Thermoacoustic (TA imaging techniques, and demonstrate its unique ability for in vivo cancer detection using tumor-bearing mice. Circular scanning TA and PA imaging systems were used to recover the dielectric and optical property distributions of three colon carcinoma bearing mice While a 7.0-T magnetic resonance imaging (MRI unit with a mouse body volume coil was utilized for high resolution structural imaging of the same mice. Three plastic tubes filled with soybean sauce were used as fiducial markers for the co-registration of MR, PA and TA images. The resulting fused images provided both enhanced tumor margin and contrast relative to the surrounding normal tissues. In particular, some finger-like protrusions extending into the surrounding tissues were revealed in the MR/TA infused images. These results show that the tissue functional optical and dielectric properties provided by PA and TA images along with the anatomical structure by MRI in one picture make accurate tumor identification easier. This combined MR–PA–TA-imaging strategy has the potential to offer a clinically useful triple-modality tool for accurate cancer detection and for intraoperative surgical navigation.

  4. Design of a Thermoacoustic Sensor for Low Intensity Ultrasound Measurements Based on an Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Jida Xing

    2015-06-01

    Full Text Available In therapeutic ultrasound applications, accurate ultrasound output intensities are crucial because the physiological effects of therapeutic ultrasound are very sensitive to the intensity and duration of these applications. Although radiation force balance is a benchmark technique for measuring ultrasound intensity and power, it is costly, difficult to operate, and compromised by noise vibration. To overcome these limitations, the development of a low-cost, easy to operate, and vibration-resistant alternative device is necessary for rapid ultrasound intensity measurement. Therefore, we proposed and validated a novel two-layer thermoacoustic sensor using an artificial neural network technique to accurately measure low ultrasound intensities between 30 and 120 mW/cm2. The first layer of the sensor design is a cylindrical absorber made of plexiglass, followed by a second layer composed of polyurethane rubber with a high attenuation coefficient to absorb extra ultrasound energy. The sensor determined ultrasound intensities according to a temperature elevation induced by heat converted from incident acoustic energy. Compared with our previous one-layer sensor design, the new two-layer sensor enhanced the ultrasound absorption efficiency to provide more rapid and reliable measurements. Using a three-dimensional model in the K-wave toolbox, our simulation of the ultrasound propagation process demonstrated that the two-layer design is more efficient than the single layer design. We also integrated an artificial neural network algorithm to compensate for the large measurement offset. After obtaining multiple parameters of the sensor characteristics through calibration, the artificial neural network is built to correct temperature drifts and increase the reliability of our thermoacoustic measurements through iterative training about ten seconds. The performance of the artificial neural network method was validated through a series of experiments. Compared

  5. Design of a Thermoacoustic Sensor for Low Intensity Ultrasound Measurements Based on an Artificial Neural Network.

    Science.gov (United States)

    Xing, Jida; Chen, Jie

    2015-06-23

    In therapeutic ultrasound applications, accurate ultrasound output intensities are crucial because the physiological effects of therapeutic ultrasound are very sensitive to the intensity and duration of these applications. Although radiation force balance is a benchmark technique for measuring ultrasound intensity and power, it is costly, difficult to operate, and compromised by noise vibration. To overcome these limitations, the development of a low-cost, easy to operate, and vibration-resistant alternative device is necessary for rapid ultrasound intensity measurement. Therefore, we proposed and validated a novel two-layer thermoacoustic sensor using an artificial neural network technique to accurately measure low ultrasound intensities between 30 and 120 mW/cm2. The first layer of the sensor design is a cylindrical absorber made of plexiglass, followed by a second layer composed of polyurethane rubber with a high attenuation coefficient to absorb extra ultrasound energy. The sensor determined ultrasound intensities according to a temperature elevation induced by heat converted from incident acoustic energy. Compared with our previous one-layer sensor design, the new two-layer sensor enhanced the ultrasound absorption efficiency to provide more rapid and reliable measurements. Using a three-dimensional model in the K-wave toolbox, our simulation of the ultrasound propagation process demonstrated that the two-layer design is more efficient than the single layer design. We also integrated an artificial neural network algorithm to compensate for the large measurement offset. After obtaining multiple parameters of the sensor characteristics through calibration, the artificial neural network is built to correct temperature drifts and increase the reliability of our thermoacoustic measurements through iterative training about ten seconds. The performance of the artificial neural network method was validated through a series of experiments. Compared to our previous

  6. Interviewing Objects: Including Educational Technologies as Qualitative Research Participants

    Science.gov (United States)

    Adams, Catherine A.; Thompson, Terrie Lynn

    2011-01-01

    This article argues the importance of including significant technologies-in-use as key qualitative research participants when studying today's digitally enhanced learning environments. We gather a set of eight heuristics to assist qualitative researchers in "interviewing" technologies-in-use (or other relevant objects), drawing on concrete…

  7. Low Mach number analysis of idealized thermoacoustic engines with numerical solution.

    Science.gov (United States)

    Hireche, Omar; Weisman, Catherine; Baltean-Carlès, Diana; Le Quéré, Patrick; Bauwens, Luc

    2010-12-01

    A model of an idealized thermoacoustic engine is formulated, coupling nonlinear flow and heat exchange in the heat exchangers and stack with a simple linear acoustic model of the resonator and load. Correct coupling results in an asymptotically consistent global model, in the small Mach number approximation. A well-resolved numerical solution is obtained for two-dimensional heat exchangers and stack. The model assumes that the heat exchangers and stack are shorter than the overall length by a factor of the order of a representative Mach number. The model is well-suited for simulation of the entire startup process, whereby as a result of some excitation, an initially specified temperature profile in the stack evolves toward a near-steady profile, eventually reaching stationary operation. A validation analysis is presented, together with results showing the early amplitude growth and approach of a stationary regime. Two types of initial excitation are used: Random noise and a small periodic wave. The set of assumptions made leads to a heat-exchanger section that acts as a source of volume but is transparent to pressure and to a local heat-exchanger model characterized by a dynamically incompressible flow to which a locally spatially uniform acoustic pressure fluctuation is superimposed.

  8. Stack Parameters Effect on the Performance of Anharmonic Resonator Thermoacoustic Heat Engine

    KAUST Repository

    Nouh, Mostafa A.; Arafa, Nadim M.; Abdel-Rahman, Ehab

    2014-01-01

    A thermoacoustic heat engine (TAHE) converts heat into acoustic power with no moving parts. It exhibits several advantages over traditional engines, such as simple design, stable functionality, and environment-friendly working gas. In order to further improve the performance of TAHE, stack parameters need to be optimized. Stack's position, length and plate spacing are the three main parameters that have been investigated in this study. Stack's position dictates both the efficiency and the maximum produced acoustic power of the heat engine. Positioning the stack closer to the pressure anti-node might ensure high efficiency on the expense of the maximum produced acoustic power. It is noticed that the TAHE efficiency can further be improved by spacing the plates of the stack at a value of 2.4 of the thermal penetration depth, δk . Changes in the stack length will not affect the efficiency much as long as the temperature gradient across the stack, as a ratio of the critical temperature gradient ψ is more than 1. Upon interpreting the effect of these variations, attempts are made towards reaching the engine's most powerful operating point.

  9. Stack Parameters Effect on the Performance of Anharmonic Resonator Thermoacoustic Heat Engine

    KAUST Repository

    Nouh, Mostafa A.

    2014-01-01

    A thermoacoustic heat engine (TAHE) converts heat into acoustic power with no moving parts. It exhibits several advantages over traditional engines, such as simple design, stable functionality, and environment-friendly working gas. In order to further improve the performance of TAHE, stack parameters need to be optimized. Stack\\'s position, length and plate spacing are the three main parameters that have been investigated in this study. Stack\\'s position dictates both the efficiency and the maximum produced acoustic power of the heat engine. Positioning the stack closer to the pressure anti-node might ensure high efficiency on the expense of the maximum produced acoustic power. It is noticed that the TAHE efficiency can further be improved by spacing the plates of the stack at a value of 2.4 of the thermal penetration depth, δk . Changes in the stack length will not affect the efficiency much as long as the temperature gradient across the stack, as a ratio of the critical temperature gradient ψ is more than 1. Upon interpreting the effect of these variations, attempts are made towards reaching the engine\\'s most powerful operating point.

  10. Microwave pumped high-efficient thermoacoustic tumor therapy with single wall carbon nanotubes.

    Science.gov (United States)

    Wen, Liewei; Ding, Wenzheng; Yang, Sihua; Xing, Da

    2016-01-01

    The ultra-short pulse microwave could excite to the strong thermoacoustic (TA) shock wave and deeply penetrate in the biological tissues. Based on this, we developed a novel deep-seated tumor therapy modality with mitochondria-targeting single wall carbon nanotubes (SWNTs) as microwave absorbing agents, which act efficiently to convert ultra-short microwave energy into TA shock wave and selectively destroy the targeted mitochondria, thereby inducing apoptosis in cancer cells. After the treatment of SWNTs (40 μg/mL) and ultra-short microwave (40 Hz, 1 min), 77.5% of cancer cells were killed and the vast majority were caused by apoptosis that initiates from mitochondrial damage. The orthotopic liver cancer mice were established as deep-seated tumor model to investigate the anti-tumor effect of mitochondria-targeting TA therapy. The results suggested that TA therapy could effectively inhibit the tumor growth without any observable side effects, while it was difficult to achieve with photothermal or photoacoustic therapy. These discoveries implied the potential application of TA therapy in deep-seated tumor models and should be further tested for development into a promising therapeutic modality for cancer treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. An analytical study of photoacoustic and thermoacoustic generation efficiency towards contrast agent and film design optimization

    Directory of Open Access Journals (Sweden)

    Fei Gao

    2017-09-01

    Full Text Available Photoacoustic (PA and thermoacoustic (TA effects have been explored in many applications, such as bio-imaging, laser-induced ultrasound generator, and sensitive electromagnetic (EM wave film sensor. In this paper, we propose a compact analytical PA/TA generation model to incorporate EM, thermal and mechanical parameters, etc. From the derived analytical model, both intuitive predictions and quantitative simulations are performed. It shows that beyond the EM absorption improvement, there are many other physical parameters that deserve careful consideration when designing contrast agents or film composites, followed by simulation study. Lastly, several sets of experimental results are presented to prove the feasibility of the proposed analytical model. Overall, the proposed compact model could work as a clear guidance and predication for improved PA/TA contrast agents and film generator/sensor designs in the domain area.

  12. Correspondence Between “Stable” Flame Macrostructure and Thermo-acoustic Instability in Premixed Swirl-Stabilized Turbulent Combustion

    KAUST Repository

    Taamallah, Soufien; LaBry, Zachary A.; Shanbhogue, Santosh J.; Habib, Mohamed A. M.; Ghoniem, Ahmed F.

    2014-01-01

    Copyright © 2015 by ASME. In this paper, we conduct an experimental investigation to study the link between the flame macroscale structure - or flame brush spatial distribution - and thermo-acoustic instabilities, in a premixed swirl-stabilized dump combustor. We operate the combustor with premixed methane-air in the range of equivalence ratio (Φ) from the lean blowout limit to Φ = 0. 75. First, we observe the different dynamic modes in this lean range as Φ is raised. We also document the effect of Φ on the flame macrostructure. Next, we examine the correspondence between dynamic mode transitions and changes in flame macrostructure. To do so, we modify the combustor length - by downstream truncation - without changing the underlying flow upstream. Thus, the resonant frequencies of the geometry are altered allowing for decoupling the heat release rate fluctuations and the acoustic feedback. Mean flame configurations in the modified combustor and for the same range of equivalence ratio are examined, following the same experimental protocol. It is found that not only the same sequence of flame macrostructures is observed in both combustors but also that the transitions occur at a similar set of equivalence ratio. In particular, the appearance of the flame in the outside recirculation zone (ORZ) in the long combustor - which occurs simultaneously with the onset of instability at the fundamental frequency - happens at similar Φ when compared to the short combustor, but without being in latter case accompanied by a transition to thermo-acoustic instability. Then, we interrogate the flow field by analyzing the streamlines, mean, and rms velocities for the nonreacting flow and the different flame types. Finally, we focus on the transition of the flame to the ORZ in the acoustically decoupled case. Our analysis of this transition shows that it occurs gradually with an intermittent appearance of a flame in the ORZ and an increasing probability with Φ. The spectral

  13. Correspondence Between “Stable” Flame Macrostructure and Thermo-acoustic Instability in Premixed Swirl-Stabilized Turbulent Combustion

    KAUST Repository

    Taamallah, Soufien

    2014-12-23

    Copyright © 2015 by ASME. In this paper, we conduct an experimental investigation to study the link between the flame macroscale structure - or flame brush spatial distribution - and thermo-acoustic instabilities, in a premixed swirl-stabilized dump combustor. We operate the combustor with premixed methane-air in the range of equivalence ratio (Φ) from the lean blowout limit to Φ = 0. 75. First, we observe the different dynamic modes in this lean range as Φ is raised. We also document the effect of Φ on the flame macrostructure. Next, we examine the correspondence between dynamic mode transitions and changes in flame macrostructure. To do so, we modify the combustor length - by downstream truncation - without changing the underlying flow upstream. Thus, the resonant frequencies of the geometry are altered allowing for decoupling the heat release rate fluctuations and the acoustic feedback. Mean flame configurations in the modified combustor and for the same range of equivalence ratio are examined, following the same experimental protocol. It is found that not only the same sequence of flame macrostructures is observed in both combustors but also that the transitions occur at a similar set of equivalence ratio. In particular, the appearance of the flame in the outside recirculation zone (ORZ) in the long combustor - which occurs simultaneously with the onset of instability at the fundamental frequency - happens at similar Φ when compared to the short combustor, but without being in latter case accompanied by a transition to thermo-acoustic instability. Then, we interrogate the flow field by analyzing the streamlines, mean, and rms velocities for the nonreacting flow and the different flame types. Finally, we focus on the transition of the flame to the ORZ in the acoustically decoupled case. Our analysis of this transition shows that it occurs gradually with an intermittent appearance of a flame in the ORZ and an increasing probability with Φ. The spectral

  14. Towards energy efficient distillation technologies – Making the right choice

    International Nuclear Information System (INIS)

    Kiss, Anton A.; Flores Landaeta, Servando J.; Infante Ferreira, Carlos A.

    2012-01-01

    In spite of claiming around half of the operational costs of chemical plants, distillation is still the most popular separation technology. Distillation has low thermodynamic efficiency, requiring the input of high quality energy in the reboiler – while rejecting a similar amount of heat at lower temperature, in the condenser. Several heat pump concepts have been proposed to upgrade that thermal energy and reduce the consumption of valuable utilities. Under certain conditions, the energy savings of heat pump assisted distillation is usually around 20–50%. This study proposes a novel selection scheme of energy efficient distillation technologies, with a special focus on heat pumps. The most promising technologies selected are vapor compression, mechanical or thermal vapor recompression, absorption, compression–resorption and thermo-acoustic heat pumps, multi-effect distillation, heat integrated distillation column, cyclic distillation, Kaibel and dividing-wall column. The scheme considers as the main selection criteria the type of separation tasks, product flow and specifications, operating pressure, difference in boiling points, reboiler duty and its temperature level. Moreover, this scheme is very practical, allowing major time and resources savings in the design of eco-efficient processes. -- Highlights: ► Heat pump assisted distillation with energy savings of 20–50%. ► Novel and practical selection scheme of energy efficient distillation technologies. ► Evaluation of promising technologies: VC, MVR, TVR, AHP, CHRP, TAHP, HIDiC, DWC, CyDist. ► Selection criteria include: ΔT b , ΔT lift , P, T reb , Q reb , volatility. ► Design of eco-efficient processes with high COP, and lower TIC and TAC.

  15. Reducing the effects of acoustic heterogeneity with an iterative reconstruction method from experimental data in microwave induced thermoacoustic tomography

    International Nuclear Information System (INIS)

    Wang, Jinguo; Zhao, Zhiqin; Song, Jian; Chen, Guoping; Nie, Zaiping; Liu, Qing-Huo

    2015-01-01

    Purpose: An iterative reconstruction method has been previously reported by the authors of this paper. However, the iterative reconstruction method was demonstrated by solely using the numerical simulations. It is essential to apply the iterative reconstruction method to practice conditions. The objective of this work is to validate the capability of the iterative reconstruction method for reducing the effects of acoustic heterogeneity with the experimental data in microwave induced thermoacoustic tomography. Methods: Most existing reconstruction methods need to combine the ultrasonic measurement technology to quantitatively measure the velocity distribution of heterogeneity, which increases the system complexity. Different to existing reconstruction methods, the iterative reconstruction method combines time reversal mirror technique, fast marching method, and simultaneous algebraic reconstruction technique to iteratively estimate the velocity distribution of heterogeneous tissue by solely using the measured data. Then, the estimated velocity distribution is used subsequently to reconstruct the highly accurate image of microwave absorption distribution. Experiments that a target placed in an acoustic heterogeneous environment are performed to validate the iterative reconstruction method. Results: By using the estimated velocity distribution, the target in an acoustic heterogeneous environment can be reconstructed with better shape and higher image contrast than targets that are reconstructed with a homogeneous velocity distribution. Conclusions: The distortions caused by the acoustic heterogeneity can be efficiently corrected by utilizing the velocity distribution estimated by the iterative reconstruction method. The advantage of the iterative reconstruction method over the existing correction methods is that it is successful in improving the quality of the image of microwave absorption distribution without increasing the system complexity

  16. Studies on thermo-acoustic parameters in binary liquid mixtures of phosphinic acid (Cyanex 272) with different diluents at temperature 303.15 K: an ultrasonic study

    International Nuclear Information System (INIS)

    Kamila, Susmita; Jena, Satyaban; Swain, Bipin Bihari

    2005-01-01

    Acoustical investigations for the binary mixtures of phosphinic acid (Cyanex 272), used as liquid-liquid extractant, have been made in various diluents such as benzene, toluene, and xylene from ultrasonic velocity and density measurements at temperature 303.15 K and atmospheric pressure. This study involves evaluation of different thermo-acoustic parameters along with the excess properties, which are interpreted in the light of molecular interaction between a polar extractant, Cyanex 272 with non-polar diluent, benzene and weakly polar diluents, toluene and xylene. The excess values are correlated using Redlich-Kister polynomial equation, and corresponding adjustable parameters are derived

  17. Thermal management of thermoacoustic sound projectors using a free-standing carbon nanotube aerogel sheet as a heat source.

    Science.gov (United States)

    Aliev, Ali E; Mayo, Nathanael K; Baughman, Ray H; Avirovik, Dragan; Priya, Shashank; Zarnetske, Michael R; Blottman, John B

    2014-10-10

    Carbon nanotube (CNT) aerogel sheets produce smooth-spectra sound over a wide frequency range (1-10(5) Hz) by means of thermoacoustic (TA) sound generation. Protective encapsulation of CNT sheets in inert gases between rigid vibrating plates provides resonant features for the TA sound projector and attractive performance at needed low frequencies. Energy conversion efficiencies in air of 2% and 10% underwater, which can be enhanced by further increasing the modulation temperature. Using a developed method for accurate temperature measurements for the thin aerogel CNT sheets, heat dissipation processes, failure mechanisms, and associated power densities are investigated for encapsulated multilayered CNT TA heaters and related to the thermal diffusivity distance when sheet layers are separated. Resulting thermal management methods for high applied power are discussed and deployed to construct efficient and tunable underwater sound projector for operation at relatively low frequencies, 10 Hz-10 kHz. The optimal design of these TA projectors for high-power SONAR arrays is discussed.

  18. Thermal management of thermoacoustic sound projectors using a free-standing carbon nanotube aerogel sheet as a heat source

    International Nuclear Information System (INIS)

    Aliev, Ali E; Mayo, Nathanael K; Baughman, Ray H; Avirovik, Dragan; Priya, Shashank; Zarnetske, Michael R; Blottman, John B

    2014-01-01

    Carbon nanotube (CNT) aerogel sheets produce smooth-spectra sound over a wide frequency range (1–10 5 Hz) by means of thermoacoustic (TA) sound generation. Protective encapsulation of CNT sheets in inert gases between rigid vibrating plates provides resonant features for the TA sound projector and attractive performance at needed low frequencies. Energy conversion efficiencies in air of 2% and 10% underwater, which can be enhanced by further increasing the modulation temperature. Using a developed method for accurate temperature measurements for the thin aerogel CNT sheets, heat dissipation processes, failure mechanisms, and associated power densities are investigated for encapsulated multilayered CNT TA heaters and related to the thermal diffusivity distance when sheet layers are separated. Resulting thermal management methods for high applied power are discussed and deployed to construct efficient and tunable underwater sound projector for operation at relatively low frequencies, 10 Hz–10 kHz. The optimal design of these TA projectors for high-power SONAR arrays is discussed. (paper)

  19. Annual Technology Baseline (Including Supporting Data); NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    Blair, Nate; Cory, Karlynn; Hand, Maureen; Parkhill, Linda; Speer, Bethany; Stehly, Tyler; Feldman, David; Lantz, Eric; Augusting, Chad; Turchi, Craig; O' Connor, Patrick

    2015-07-08

    Consistent cost and performance data for various electricity generation technologies can be difficult to find and may change frequently for certain technologies. With the Annual Technology Baseline (ATB), National Renewable Energy Laboratory provides an organized and centralized dataset that was reviewed by internal and external experts. It uses the best information from the Department of Energy laboratory's renewable energy analysts and Energy Information Administration information for conventional technologies. The ATB will be updated annually in order to provide an up-to-date repository of current and future cost and performance data. Going forward, we plan to revise and refine the values using best available information. The ATB includes both a presentation with notes (PDF) and an associated Excel Workbook. The ATB includes the following electricity generation technologies: land-based wind; offshore wind; utility-scale solar PV; concentrating solar power; geothermal power; hydropower plants (upgrades to existing facilities, powering non-powered dams, and new stream-reach development); conventional coal; coal with carbon capture and sequestration; integrated gasification combined cycle coal; natural gas combustion turbines; natural gas combined cycle; conventional biopower. Nuclear laboratory's renewable energy analysts and Energy Information Administration information for conventional technologies. The ATB will be updated annually in order to provide an up-to-date repository of current and future cost and performance data. Going forward, we plan to revise and refine the values using best available information.

  20. Experimental analysis of thermo-acoustic instabilities in a generic gas turbine combustor by phase-correlated PIV, chemiluminescence, and laser Raman scattering measurements

    Science.gov (United States)

    Arndt, Christoph M.; Severin, Michael; Dem, Claudiu; Stöhr, Michael; Steinberg, Adam M.; Meier, Wolfgang

    2015-04-01

    A gas turbine model combustor for partially premixed swirl flames was equipped with an optical combustion chamber and operated with CH4 and air at atmospheric pressure. The burner consisted of two concentric nozzles for separately controlled air flows and a ring of holes 12 mm upstream of the nozzle exits for fuel injection. The flame described here had a thermal power of 25 kW, a global equivalence ratio of 0.7, and exhibited thermo-acoustic instabilities at a frequency of approximately 400 Hz. The phase-dependent variations in the flame shape and relative heat release rate were determined by OH* chemiluminescence imaging; the flow velocities by stereoscopic particle image velocimetry (PIV); and the major species concentrations, mixture fraction, and temperature by laser Raman scattering. The PIV measurements showed that the flow field performed a "pumping" mode with varying inflow velocities and extent of the inner recirculation zone, triggered by the pressure variations in the combustion chamber. The flow field oscillations were accompanied by variations in the mixture fraction in the inflow region and at the flame root, which in turn were mainly caused by the variations in the CH4 concentration. The mean phase-dependent changes in the fluxes of CH4 and N2 through cross-sectional planes of the combustion chamber at different heights above the nozzle were estimated by combining the PIV and Raman data. The results revealed a periodic variation in the CH4 flux by more than 150 % in relation to the mean value, due to the combined influence of the oscillating flow velocity, density variations, and CH4 concentration. Based on the experimental results, the feedback mechanism of the thermo-acoustic pulsations could be identified as a periodic fluctuation of the equivalence ratio and fuel mass flow together with a convective delay for the transport of fuel from the fuel injector to the flame zone. The combustor and the measured data are well suited for the validation of

  1. 76 FR 175 - Faurecia Emissions Control Technologies Including On-Site Leased Workers From Adecco Employment...

    Science.gov (United States)

    2011-01-03

    ... Technologies Including On-Site Leased Workers From Adecco Employment Servcies and Emcon Technologies, Troy, MI..., applicable to workers of Faurecia Emissions Control Technologies, Troy, Michigan, including on-site leased workers from Adecco Employment Services, Troy, Michigan. The Department's notice of determination was...

  2. Linear Acoustic Nuclear Conversion Engine (LANCE), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Nirvana Energy Systems (NES) has pioneered and is commercializing an innovative ThermoAcoustic Power Stick (TAPS), partially based on technology developed by Xerox...

  3. Using virtual reality technology to include field operators in simulation and training

    International Nuclear Information System (INIS)

    Nystad, E.; Strand, S.

    2006-01-01

    By using virtual reality technology, field operators can be included in simulator training. A study has been performed where field operators could perform their activities in a virtual plant and communicate with a control room operator who was placed in a physical control room simulator. This paper describes the use of VR technology in the study and how the operators experienced interacting with the virtual plant. (author)

  4. 75 FR 43555 - Experian, Global Technology Services, a Subsidiary of Experian, Including a Leased Employee From...

    Science.gov (United States)

    2010-07-26

    ... Technology Services, a Subsidiary of Experian, Including a Leased Employee From Tapfin Working Off-Site in... Experian, Global Technology Services, a subsidiary of Experian, including on-site leased workers from... control of the Schaumburg, Illinois location of Experian, Global Technology Services, a subsidiary of...

  5. Microwave technology for waste management applications including disposition of electronic circuitry

    International Nuclear Information System (INIS)

    Wicks, G.G.; Clark, D.E.; Schulz, R.L.; Folz, D.C.

    1995-01-01

    Microwave technology is being developed nationally and internationally for a variety of environmental remediation purposes. These efforts include treatment and destruction of a vast array of gaseous, liquid and solid hazardous wastes as well as subsequent immobilization of selected components. Microwave technology provides an important contribution to an arsenal of existing remediation methods that are designed to protect the public and environment from undesirable consequences of hazardous materials. Applications of microwave energy for environmental remediation will be discussed. Emphasized will be a newly developed microwave process designed to treat discarded electronic circuitry and reclaim the precious metals within for reuse

  6. 76 FR 2144 - Quest Diagnostics, Inc. Information Technology Help Desk Services Including On-Site Leased...

    Science.gov (United States)

    2011-01-12

    .... Information Technology Help Desk Services Including On-Site Leased Workers From Modis, West Norriton, PA..., applicable to workers of Quest Diagnostics, Inc., Information Technology Help Desk Services, West Norriton... Quest Diagnostics, Inc., Information Technology Help Desk [[Page 2145

  7. Microwave Technology for Waste Management Applications Including Disposition of Electronic Circuitry

    International Nuclear Information System (INIS)

    Wicks, G.G.; Clark, D.E.; Schulz, R.L.

    1998-01-01

    Advanced microwave technology is being developed nationally and internationally for a variety of waste management and environmental remediation purposes. These efforts include treatment and destruction of a vast array of gaseous, liquid and solid hazardous wastes as well as subsequent immobilization of hazardous components into leach resistant forms. Microwave technology provides an important contribution to an arsenal of existing remediation methods that are designed to protect the public and environment from the undesirable consequences of hazardous materials. One application of special interest is the treatment of discarded electronic circuitry using a new hybrid microwave treatment process and subsequent reclamation of the precious metals within

  8. Thermal energy harvesting for application at MEMS scale

    CERN Document Server

    Percy, Steven; McGarry, Scott; Post, Alex; Moore, Tim; Cavanagh, Kate

    2014-01-01

    This book discusses the history of thermal heat generators and focuses on the potential for these processes using micro-electrical mechanical systems (MEMS) technology for this application. The main focus is on the capture of waste thermal energy for example from industrial processes, transport systems or the human body to generate useable electrical power.  A wide range of technologies is discussed, including external combustion heat cycles at MEMS ( Brayton, Stirling and Rankine), Thermoacoustic, Shape Memory Alloys (SMAs), Multiferroics, Thermionics, Pyroelectric, Seebeck, Alkali Metal Thermal, Hydride Heat Engine, Johnson Thermo Electrochemical Converters, and the Johnson Electric Heat Pipe.

  9. Investigation of Techno-Stress Levels of Teachers Who Were Included in Technology Integration Processes

    Science.gov (United States)

    Çoklar, Ahmet Naci; Efilti, Erkan; Sahin, Yusef Levent; Akçay, Arif

    2016-01-01

    Techno-stress is defined as a modern adaptation disorder resulting from the failure in coping with new technologies in a healthy way. Techno-stress affects many occupational groups, including teachers. FATIH project and many other previous studies conducted in Turkey in recent years have necessitated the use of technology for teachers. The present…

  10. 76 FR 32227 - DST Systems, Inc., Including On-Site Leased Workers From Comsys Information Technology Services...

    Science.gov (United States)

    2011-06-03

    ..., Inc., Including On-Site Leased Workers From Comsys Information Technology Services, Megaforce, and Kelly Services Kansas City, MO; DST Technologies, a Wholly Owned Subsidiary of DST Systems, Inc., Boston... Information Technology Services, Megaforce, and Kelly Services, Kansas City, Missouri (subject firm). The...

  11. Application of particle image velocimetry measurement techniques to study turbulence characteristics of oscillatory flows around parallel-plate structures in thermoacoustic devices

    International Nuclear Information System (INIS)

    Mao, Xiaoan; Jaworski, Artur J

    2010-01-01

    This paper describes the development of the experimental setup and measurement methodologies to study the physics of oscillatory flows in the vicinity of parallel-plate stacks by using the particle image velocimetry (PIV) techniques. Parallel-plate configurations often appear as internal structures in thermoacoustic devices and are responsible for the hydrodynamic energy transfer processes. The flow around selected stack configurations is induced by a standing acoustic wave, whose amplitude can be varied. Depending on the direction of the flow within the acoustic cycle, relative to the stack, it can be treated as an entrance flow or a wake flow. The insight into the flow behaviour, its kinematics, dynamics and scales of turbulence, is obtained using the classical Reynolds decomposition to separate the instantaneous velocity fields into ensemble-averaged mean velocity fields and fluctuations in a set of predetermined phases within an oscillation cycle. The mean velocity field and the fluctuation intensity distributions are investigated over the acoustic oscillation cycle. The velocity fluctuation is further divided into large- and small-scale fluctuations by using fast Fourier transform (FFT) spatial filtering techniques

  12. Resonance – Journal of Science Education | Indian Academy of ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 11. Eco-Friendly Alternative Refrigeration Systems - Thermoacoustic ... Author Affiliations. S S Verma1. Department of Physics, Sant Longowol Institute of Engineering and Technology Longowal, District Songrur Punjab 148 106. India.

  13. Experimental investigation of the influence of natural convection and end-effects on Rayleigh streaming in a thermoacoustic engine.

    Science.gov (United States)

    Ramadan, Islam A; Bailliet, Hélène; Valière, Jean-Christophe

    2018-01-01

    The influence of both the natural convection and end-effects on Rayleigh streaming pattern in a simple standing-wave thermoacoustic engine is investigated experimentally at different acoustic levels. The axial mean velocity inside the engine is measured using both Laser Doppler Velocimetry and Particle Image Velocimetry. The mean flow patterns are categorized in three different regions referred to as "cold streaming" region, "hot streaming" region, and "end-effects" region. In the cold streaming region, the dominant phenomenon is Rayleigh streaming and the mean velocity measurements correspond well with the theoretical expectations of Rayleigh streaming at low acoustic levels. At higher acoustic levels, the measurements deviate from the theoretical expectations which complies with the literature. In the hot streaming region, temperature measurements reveal that the non-uniformity of the resonator wall temperature is the origin of natural convection flow. Velocity measurements show that natural convection flow superimposes on the Rayleigh streaming flow so that the measured mean velocity deviates from the theoretical expectations of Rayleigh streaming. In the last region, the measured mean velocity is very different from Rayleigh streaming due to the combined effects of both the flow disturbances generated near the extremity of the stack and the natural convection flow.

  14. Thermo-Acoustic Properties of a Burner with Axial Temperature Gradient: Theory and Experiment

    Directory of Open Access Journals (Sweden)

    Béla Kosztin

    2013-03-01

    Full Text Available This paper presents a model for thermo-acoustic effects in a gas turbine combustor. A quarter-wavelength burner with rectangular cross-section has been built and studied from an experimental and theoretical perspective. It has a premixed methane-air flame, which is held by a bluff body, and spans the width of the burner. The flame is compact, i.e. its length is much smaller than that of the burner. The fundamental mode of the burner is unstable; its frequency and pressure distribution have been measured. The complex pressure reflection coefficients at the upstream and downstream end of the burner were also measured. For the theoretical considerations, we divide the burner into three regions (the cold pre-combustion chamber, the flame region and the hot outlet region, and assume one-dimensional acoustic wave propagation in each region. The acoustic pressure and velocity are assumed continuous across the interface between the precombustion chamber and flame region, and across the interface between the flame region and outlet region. The burner ends are modelled by the measured pressure reflection coefficients. The mean temperature is assumed to have the following profile: uniformly cold and uniformly hot in the pre-combustion chamber and outlet region, respectively, and rising continuously from cold to hot in the flame region. For comparison, a discontinuous temperature profile, jumping directly from cold to hot, is also considered. The eigenfrequencies are calculated, and the pressure distribution of the fundamental mode is predicted. There is excellent agreement with the experimental results. The exact profile of the mean temperature in the flame region is found to be unimportant. This study gives us an experimentally validated Green's function, which is a very useful tool for further theoretical studies.

  15. 76 FR 35474 - UAW-Chrysler Technical Training Center, Technology Training Joint Programs Staff, Including On...

    Science.gov (United States)

    2011-06-17

    ...-Chrysler Technical Training Center, Technology Training Joint Programs Staff, Including On-Site Leased Workers From Cranks, O/E Learning, DBSI, IDEA, and Tonic/MVP, Detroit, MI; UAW-Chrysler Technical Training... workers and former workers of UAW-Chrysler Technical Training Center, Technology Training Joint Programs...

  16. Numerical investigation on nonlinear effect and vortex formation of oscillatory flow throughout a short tube in a thermoacoustic Stirling engine

    Science.gov (United States)

    Yang, Peng; Chen, Hui; Liu, Yingwen

    2017-06-01

    In this paper, a two-dimensional axisymmetric model of a thermoacoustic Stirling engine with a short tube where the cross section narrows has been developed. The transient streamlines and vortex formation through short tubes with different diameters in oscillatory flow have been investigated visually by computational fluid dynamics. Three dimensionless parameters, Reynolds number (Re), Keulegan-Carpenter number (KC), and Womersley number (Wo), are used to describe the flow regime and vortex characteristic throughout the short tube. High Re and Wo numbers indicate that the oscillatory flow develops into the turbulent flow through the short tube. The KC number has a direct effect on the transition of streamlines and the development of the vortex. For a small cross section where KC ≈ 1, streamlines rotate and the vortex forms at both sides of the short tube. The vortex stays in the main flow region, and intensity varies as streamlines are convected downstream. The velocity along the radius presents a Poiseuille profile within the influence of the vortex. For a large cross section where KC < 1, streamlines pass the short tube with little rotation and the vortex disappears in the main flow region and confines near the short tube. The velocity profile tends to be flat. The nonlinear effects including instantaneous pressure drop and power dissipation throughout the short tube are also discussed. It shows that the time averaged pressure drop is generated at the cost of power dissipation. Finally, the "effectiveness" is applied to evaluate the performance of the short tube. The results suggest that increasing the diameter of the short tube is in favor of reducing power dissipation, which is beneficial to improve "effectiveness."

  17. Script of Healthcare Technology: Do Designs of Robotic Beds Exclude or Include Users?

    DEFF Research Database (Denmark)

    Brodersen, Søsser Grith Kragh; Hansen, Meiken; Lindegaard, Hanne

    2015-01-01

    Many new product designs are currently being implemented in the healthcare sector, and this presents designers with challenges involved in socially innovative design. In this paper, we argue that designing assistive technologies requires focus on multiple users and use practices. We see the design...... of assistive technologies as design of socio-material assemblies , which include an analysis of the products already used in relation to multiple users, their practices and wishes. In the article we focus on the challenges in the implementation of two types of robotic beds used for disability care...

  18. 2-d LIF measurements of the thermo-acoustic phenomena in lean premixed flames of a gas turbine combustor

    Energy Technology Data Exchange (ETDEWEB)

    Bombach, R.; Hubschmid, W.; Inauen, A.; Kreutner, W.; Schenker, S.; Flohr, P.; Haffner, K.; Motz, C.; Paschereit, C.O.; Schuermans, B.; Zajadatz, M.

    2003-03-01

    Thermo-acoustic phenomena give rise to pressure oscillations in lean premixed flames of gas turbines at distinct frequencies characteristic of the burner design and its operation. They can lead to early materials ageing or even severe damages. Therefore, a detailed understanding of the underlying principles is fundamental for gas turbine design and improvement. In order to study the coupling between the heat release and the acoustics in the combustor as well as their feedback to the fuel/air premixing, upstream of the combustion chamber, phase-locked 2-D laser-induced fluorescence (LIF) measurements of the hydroxyl radical (OH) and acetone, respectively, have been performed. These experiments were carried out on a test rig equipped with a commercial 700 kW burner and a combustion chamber of UV transparent quartz, using a pulsed Nd:YAG/dye laser system and an intensified CCD camera for detection. Intensity variations in the integral OH LIF signal of up to {+-}10 % for one oscillation period are observed for peak sound pressure of 6 mbar and more. In addition, the phase-averaged position of the flame zone varies in axial direction, i.e. the main flow direction. The analysis shows that the observed flame motion is not only due to the acoustic motion of the gas itself, but is caused by a change of the flame velocity relative to the gas. (author)

  19. 75 FR 66795 - TTM Technologies, Including On-Site Leased Workers From Kelly Services, Aerotek, and an On-Site...

    Science.gov (United States)

    2010-10-29

    ... follows: ``All workers TTM Technologies, including on-site leased workers from Kelly Services and Aerotek... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-64,993] TTM Technologies, Including On-Site Leased Workers From Kelly Services, Aerotek, and an On-Site Leased Worker From Orbotech...

  20. 32 CFR 37.875 - Should my TIA include a provision concerning foreign access to technology?

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 1 2010-07-01 2010-07-01 false Should my TIA include a provision concerning... Related to Other Administrative Matters Intellectual Property § 37.875 Should my TIA include a provision... provision in the TIA that addresses foreign access to technology developed under the TIA. (b) The provision...

  1. 77 FR 40638 - Syniverse Technologies, Inc., Including On-Site Leased Workers From Insight Global Stone Staffing...

    Science.gov (United States)

    2012-07-10

    ..., Inc., Including On-Site Leased Workers From Insight Global Stone Staffing, and Randstad Formerly Known..., Massachusetts, including on-site leased workers from Insight Global, Stone Staffing, Randstad formerly known as... Insight Global, Stone Staffing, Randstad, formerly known as Sapphire Technologies, were employed on-site...

  2. Scanning Microwave Induced Acoustic Tomography

    National Research Council Canada - National Science Library

    Wang, Lihong V

    2002-01-01

    .... Specifically, our accomplishments include (1) an exact and an approximate time-domain reconstruction algorithm for thermoacoustic tomography in a spherical geometry was derived and published, (2...

  3. Joint Aircraft Survivability Program Final Test Report for the Acoustic Fire Suppression Project JASP-TR-14-05

    Science.gov (United States)

    2016-09-01

    Unlike traditional coil speakers that produce sound through mechanical vibration , thin-film CNTs are thermoacoustic actuators. Acoustic sound is a...extinction. The model was based on the ratio of an acoustic Nusselt Number to the Spalding B Number of the fuel, and it was found that at the minimum speaker ...then used to design criteria for a prototype carbon nanotube (CNT) thermoacoustic speaker . Of the 3 designs fabricated, none of the CNT thermoacoustic

  4. 78 FR 8587 - Thomson Reuters, Finance Operations & Technology Division, Including On-Site Leased Workers From...

    Science.gov (United States)

    2013-02-06

    ... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-81,755] Thomson Reuters, Finance Operations & Technology Division, Including On-Site Leased Workers From Adecco; Eagan, MN; Amended Certification Regarding Eligibility To Apply for Worker Adjustment Assistance In accordance with Section 223 of the Trade Act of 1974, as amended (`...

  5. Exploration Technology Development including Surface Acoustic Wave RFID chips

    Data.gov (United States)

    National Aeronautics and Space Administration — This project is focused on maturing future surface exploration technologies and instrumentation and working towards flight instrumentation and systems to support...

  6. Thermoacoustic Imaging and Therapy Guidance based on Ultra-short Pulsed Microwave Pumped Thermoelastic Effect Induced with Superparamagnetic Iron Oxide Nanoparticles.

    Science.gov (United States)

    Wen, Liewei; Yang, Sihua; Zhong, Junping; Zhou, Quan; Xing, Da

    2017-01-01

    Multifunctional nanoparticle-mediated imaging and therapeutic techniques are promising modalities for accurate localization and targeted treatment of cancer in clinical settings. Thermoacoustic (TA) imaging is highly sensitive to detect the distribution of water, ions or specific nanoprobes and provides excellent resolution, good contrast and superior tissue penetrability. TA therapy is a potential non-invasive approach for the treatment of deep-seated tumors. In this study, human serum albumin (HSA)-functionalized superparamagnetic iron oxide nanoparticle (HSA-SPIO) is used as a multifunctional nanoprobe with clinical application potential for MRI, TA imaging and treatment of tumor. In addition to be a MRI contrast agent for tumor localization, HSA-SPIO can absorb pulsed microwave energy and transform it into shockwave via the thermoelastic effect. Thereby, the reconstructed TA image by detecting TA signal is expected to be a sensitive and accurate representation of the HSA-SPIO accumulation in tumor. More importantly, owing to the selective retention of HSA-SPIO in tumor tissues and strong TA shockwave at the cellular level, HSA-SPIO induced TA effect under microwave-pulse radiation can be used to highly-efficiently kill cancer cells and inhibit tumor growth. Furthermore, ultra-short pulsed microwave with high excitation efficiency and deep penetrability in biological tissues makes TA therapy a highly-efficient anti-tumor modality on the versatile platform. Overall, HSA-SPIO mediated MRI and TA imaging would offer more comprehensive diagnostic information and enable dynamic visualization of nanoagents in the tumorous tissue thereby tumor-targeted therapy.

  7. Quality at a price you can afford

    Science.gov (United States)

    Garrett, Steven; Smith, Robert; Poese, Matthew

    2005-09-01

    The transition of thermoacoustics from the laboratory to the commercial sector involves a process that is very different from science. In the laboratory, when an experiment fails to produce the expected result, it is possible to make modifications, followed by further measurements, to isolate the discrepancy. After discussions with nearly 40 different companies over the past 5 years, there is rarely any feedback about why a given company decides not to proceed. In such an open-loop environment, we are left with only speculation regarding this obscure process. This talk will postulate some reasons that have led to our failure, thus far, to team with an early adaptor of the technology. These include their general lack of familiarity with acoustics, difficulties surrounding licensing of existing and future intellectual property controlled by a university, and the drift away from the maintenance of an active in-house research capability in industry [see H. W. Chesbrough, Open Innovation (Harvard, 2003)]. The sequence of events that lead to formation of the ThermoAcoustics Corporation, an investor-funded start-up, will be related, along with the changes that licensure of intellectual property have made to our ability to deal with industry on a business-to-business basis without intervention of university tech-transfer professionals.

  8. High-efficiency photovoltaic technology including thermoelectric generation

    Science.gov (United States)

    Fisac, Miguel; Villasevil, Francesc X.; López, Antonio M.

    2014-04-01

    Nowadays, photovoltaic solar energy is a clean and reliable source for producing electric power. Most photovoltaic systems have been designed and built up for use in applications with low power requirements. The efficiency of solar cells is quite low, obtaining best results in monocrystalline silicon structures, with an efficiency of about 18%. When temperature rises, photovoltaic cell efficiency decreases, given that the short-circuit current is slightly increased, and the open-circuit voltage, fill factor and power output are reduced. To ensure that this does not affect performance, this paper describes how to interconnect photovoltaic and thermoelectric technology into a single structure. The temperature gradient in the solar panel is used to supply thermoelectric cells, which generate electricity, achieving a positive contribution to the total balance of the complete system.

  9. Thermo-acoustical analysis of sodium dodecyl sulfate: Fluconazole (antifungal drug) based micellar system in hydro-ethanol solutions for potential drug topical application

    International Nuclear Information System (INIS)

    Bhardwaj, Tarun; Bhardwaj, Varun; Sharma, Kundan; Gupta, Abhishek; Cameotra, Swaranjit Singh; Sharma, Poonam

    2014-01-01

    Highlights: • The mixed micellar system was analyzed for sodium dodecyl sulfate and fluconazole. • Early micellization was found with CMC shift towards lower surfactant concentration. • Negative ΔG m o values suggested that the micelle formation is spontaneous and feasible. • Thermo-acoustical parameters revealed the existence of intermolecular interactions within the molecules. - Abstract: Micellar systems hold excellent drug delivery applications due to their capability to solubilize a large number of hydrophobic and hydrophilic molecules. In this present work, the mixed micelle formation between the anionic surfactant sodium dodecyl sulfate (SDS) and the ‘Azole’ derivative antifungal drug fluconazole (FLZ) have been studied at four temperatures in different hydro-ethanolic solutions. The critical micelle concentration (CMC) was determined by specific conductance techniques and the experimental data was used to calculate several useful thermodynamic parameters, like standard free energy, enthalpy and entropy of micelle formation. Early micellization was found with critical micelle concentration shifting towards lower concentration (CMC) than the standard concentration of SDS in water at 25 °C suggesting that drug and the solvent system facilitates the micellization process. In addition, the transport properties were examined by employing controlled approaches likely, apparent molar volume (ϕ v ), apparent molar adiabatic compression (ϕ k ), and isentropic compression (κ s ) of SDS in presence of FLZ. These parameters revealed the existence of intermolecular interactions within the molecules. Therefore, this study would cast light on utilizing surfactant immobilized FLZ system for better topical biological action

  10. Milk Technological Properties as Affected by Including Artichoke By-Products Silages in the Diet of Dairy Goats

    Directory of Open Access Journals (Sweden)

    Raquel Muelas

    2017-12-01

    Full Text Available Traditional farming practices include the use of local agricultural by-products in the diet of ruminants. Artichoke harvesting and transformation yield high amounts of by-products that, if properly used, may reduce farming costs and the environmental impact of farming. The present study tests the inclusion of silages from artichoke by-products (plant and outer bracts in the diet of dairy goats (0%, 12.5% and 25% inclusion on the technological and sensory properties of milk during a five-month study. Milk composition, color, stability, coagulation and fermentation properties remained unaffected by diet changes. Panelists were not able to differentiate among yogurts obtained from those milks by discriminant triangular sensory tests. Silages of artichoke by-products can be included in isoproteic and isoenergetic diets for dairy goats, up to a 25% (feed dry matter, without negatively affecting milk technological and sensory properties whereas reducing feeding costs.

  11. 75 FR 71464 - Metlife Technology, Operations, and Information Technology Groups Including On-Site Leased...

    Science.gov (United States)

    2010-11-23

    ... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-73,210; TA-W-73,210A] Metlife... negative determination regarding the eligibility of workers and former workers of MetLife, Technology... revised certification, and all workers in the group threatened with total or partial separation from...

  12. Thermo-acoustic instabilities of high-frequency combustion in rocket engines; Instabilites thermo-acoustiques de combustion haute-frequence dans les moteurs fusees

    Energy Technology Data Exchange (ETDEWEB)

    Cheuret, F

    2005-10-15

    Rocket motors are confined environments where combustion occurs in extreme conditions. Combustion instabilities can occur at high frequencies; they are tied to the acoustic modes of the combustion chamber. A common research chamber, CRC, allows us to study the response of a turbulent two-phase flame to acoustic oscillations of low or high amplitudes. The chamber is characterised under cold conditions to obtain, in particular, the relative damping coefficient of acoustic oscillations. The structure and frequency of the modes are determined in the case where the chamber is coupled to a lateral cavity. We have used a powder gun to study the response to a forced acoustic excitation at high amplitude. The results guide us towards shorter flames. The injectors were then modified to study the combustion noise level as a function of injection conditions. The speed of the gas determines whether the flames are attached or lifted. The noise level of lifted flames is higher. That of attached flames is proportional to the Weber number. The shorter flames whose length is less than the radius of the CRC, necessary condition to obtain an effective coupling, are the most sensitive to acoustic perturbations. The use of a toothed wheel at different positions in the chamber allowed us to obtain informations on the origin of the thermo-acoustic coupling, main objective of this thesis. The flame is sensitive to pressure acoustic oscillations, with a quasi-zero response time. These observations suggest that under the conditions of the CRC, we observe essentially the response of chemical kinetics to pressure oscillations. (author)

  13. Acoustic signal recovery by thermal demodulation

    Science.gov (United States)

    Boullosa, R. R.; Santillán, Arturo O.

    2006-10-01

    One operating mode of recently developed thermoacoustic transducers is as an audio speaker that uses an input superimposed on a direct current; as a result, the audio signal occurs at the same frequency as the input signal. To extend the potential applications of these kinds of sources, the authors propose an alternative driving mode in which a simple thermoacoustic device, consisting of a metal film over a substrate and a heat sink, is excited with a high frequency sinusoid that is amplitude modulated by a lower frequency signal. They show that the modulating signal is recovered in the radiated waves due to a mechanism that is inherent to this type of thermoacoustic process. If the frequency of the carrier is higher than 30kHz and any modulating signal (the one of interest) is in the audio frequency range, only this signal will be heard. Thus, the thermoacoustic device operates as an audio-band, self-demodulating speaker.

  14. Expanding Health Technology Assessments to Include Effects on the Environment

    DEFF Research Database (Denmark)

    Marsh, Kevin; Ganz, Michael Lee; Hsu, John

    2016-01-01

    decision makers. Health care is an important and sizable sector of the economy that could warrant closer policy attention to its impact on the environment. Considerable work is needed to track decision makers' demands, augment the environmental evidence base, and develop robust methods for capturing......There is growing awareness of the impact of human activity on the climate and the need to stem this impact. Public health care decision makers from Sweden and the United Kingdom have started examining environmental impacts when assessing new technologies. This article considers the case...... and objectives extending beyond health care. Two types of challenges hinder this process. First, the nascent evidence base is insufficient to support the accurate comparison of technologies' environmental impacts. Second, cost-utility analysis, which is favored by many HTA agencies, could capture some...

  15. Expanding Health Technology Assessments to Include Effects on the Environment.

    Science.gov (United States)

    Marsh, Kevin; Ganz, Michael L; Hsu, John; Strandberg-Larsen, Martin; Gonzalez, Raquel Palomino; Lund, Niels

    2016-01-01

    There is growing awareness of the impact of human activity on the climate and the need to stem this impact. Public health care decision makers from Sweden and the United Kingdom have started examining environmental impacts when assessing new technologies. This article considers the case for incorporating environmental impacts into the health technology assessment (HTA) process and discusses the associated challenges. Two arguments favor incorporating environmental impacts into HTA: 1) environmental changes could directly affect people's health and 2) policy decision makers have broad mandates and objectives extending beyond health care. Two types of challenges hinder this process. First, the nascent evidence base is insufficient to support the accurate comparison of technologies' environmental impacts. Second, cost-utility analysis, which is favored by many HTA agencies, could capture some of the value of environmental impacts, especially those generating health impacts, but might not be suitable for addressing broader concerns. Both cost-benefit and multicriteria decision analyses are potential methods for evaluating health and environmental outcomes, but are less familiar to health care decision makers. Health care is an important and sizable sector of the economy that could warrant closer policy attention to its impact on the environment. Considerable work is needed to track decision makers' demands, augment the environmental evidence base, and develop robust methods for capturing and incorporating environmental data as part of HTA. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  16. Contemporary Aspects of Marketing in Clinical Trials Including Segments of IT and Technology Transfer

    Science.gov (United States)

    Stamenovic, Milorad; Dobraca, Amra; Smajlovic, Mersiha

    2018-01-01

    Introduction: The aim of this paper is to present the marketing strategy and the application of management (marketing management) and advertising in order to increase the efficiency of innovative approach in clinical trials that include and involve the use of new technologies and transfer of technologies. Material and Methods: This paper has a descriptive character and represents a narrative review of the literature and new model implementation. Results: Marketing models are primarily used to improve the inclusion of a larger (and appropriate) number of patients, but they can be credited for the stay and monitoring of patients in the trial. Regulatory mechanisms play an important role in the application of various marketing strategies within clinical trials. The value for the patient as the most important stakeholder is defined in the field of clinical trials according to Kotler’s value model for the consumer. Conclusion: In order to achieve the best results it is important to adequately examine all the elements of clinical trials and apply this knowledge in creation of a marketing plan that will be made in accordance with the legal regulations defined globally and locally. In this paper, two challenges have been highlighted for the adequate application of marketing tools in the field of clinical trials, namely: defining business elements in order to provide an adequate marketing approach for clinical trials and technology transfer and ensuring uniformity and regulatory affirmation of marketing attitudes in clinical trials in all regions in which they are carried out in accordance with ICH-GCP and valid regulations. PMID:29719318

  17. Contemporary Aspects of Marketing in Clinical Trials Including Segments of IT and Technology Transfer.

    Science.gov (United States)

    Stamenovic, Milorad; Dobraca, Amra; Smajlovic, Mersiha

    2018-01-01

    The aim of this paper is to present the marketing strategy and the application of management (marketing management) and advertising in order to increase the efficiency of innovative approach in clinical trials that include and involve the use of new technologies and transfer of technologies. This paper has a descriptive character and represents a narrative review of the literature and new model implementation. Marketing models are primarily used to improve the inclusion of a larger (and appropriate) number of patients, but they can be credited for the stay and monitoring of patients in the trial. Regulatory mechanisms play an important role in the application of various marketing strategies within clinical trials. The value for the patient as the most important stakeholder is defined in the field of clinical trials according to Kotler's value model for the consumer. In order to achieve the best results it is important to adequately examine all the elements of clinical trials and apply this knowledge in creation of a marketing plan that will be made in accordance with the legal regulations defined globally and locally. In this paper, two challenges have been highlighted for the adequate application of marketing tools in the field of clinical trials, namely: defining business elements in order to provide an adequate marketing approach for clinical trials and technology transfer and ensuring uniformity and regulatory affirmation of marketing attitudes in clinical trials in all regions in which they are carried out in accordance with ICH-GCP and valid regulations.

  18. Day lighting Simulation and Thermoacoustic Laser Development for the Enhanced Utilization of Highly Concentrated Solar Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Won Jong

    2011-02-15

    Solar energy has been used in various fields, because it is clean and reliable. The present study explored the use of sunlight in two important areas which make it competitive and also attractive. First, we carried out a series of computer simulations for using sun pipes to introduce sunlight into the interior of a building. The focus was made onto the enhancement of visual environment when natural daylight is delivered to a classroom. While daylighting provides efficient means to harness the sun's abundant energy, it still leaves much room for further exploitation. With the aid of simple optical devices, sunlight could be easily concentrated and utilized. Solar-powered Thermal Acoustic(TA) lasers make one of these applications, which we explored as the other important area of solar utilization. 1) Daylighting simulation A lightless space with the dimension of a typical classroom at Jeju National University was modeled by ECOTECT. Two different cases were simulated and analyzed by RADIANCE. In the first case, a comparative analysis of illuminance was carried out to estimate the basic performance of sun pipe systems. In the other case, different designs of sun pipe systems were analyzed to elicit the most efficient model of operation. Simulations were performed for solar noon which indicates the time (or point) in the sun's path at which the sun is on the local meridian. Results show that indoor visual environment could be greatly enhanced with the application of sun pipe systems. The maximum illuminance took place with the sun pipe system of 1.0m in diameter and 0.5m in height. 2) Thermo-Acoustic Laser(TAL) development A series of experiments were carried out to find the most optimum operating conditions for the maximum SPL(Sound Pressure Level) and frequency of the acoustic waves generated by ThermoAcoustic(TA) lasers. Among various experimental variables, we focused our research on the stack position, stack length, length of the resonance tube and input

  19. Day lighting Simulation and Thermoacoustic Laser Development for the Enhanced Utilization of Highly Concentrated Solar Radiation

    International Nuclear Information System (INIS)

    Oh, Won Jong

    2011-02-01

    Solar energy has been used in various fields, because it is clean and reliable. The present study explored the use of sunlight in two important areas which make it competitive and also attractive. First, we carried out a series of computer simulations for using sun pipes to introduce sunlight into the interior of a building. The focus was made onto the enhancement of visual environment when natural daylight is delivered to a classroom. While daylighting provides efficient means to harness the sun's abundant energy, it still leaves much room for further exploitation. With the aid of simple optical devices, sunlight could be easily concentrated and utilized. Solar-powered Thermal Acoustic(TA) lasers make one of these applications, which we explored as the other important area of solar utilization. 1) Daylighting simulation A lightless space with the dimension of a typical classroom at Jeju National University was modeled by ECOTECT. Two different cases were simulated and analyzed by RADIANCE. In the first case, a comparative analysis of illuminance was carried out to estimate the basic performance of sun pipe systems. In the other case, different designs of sun pipe systems were analyzed to elicit the most efficient model of operation. Simulations were performed for solar noon which indicates the time (or point) in the sun's path at which the sun is on the local meridian. Results show that indoor visual environment could be greatly enhanced with the application of sun pipe systems. The maximum illuminance took place with the sun pipe system of 1.0m in diameter and 0.5m in height. 2) Thermo-Acoustic Laser(TAL) development A series of experiments were carried out to find the most optimum operating conditions for the maximum SPL(Sound Pressure Level) and frequency of the acoustic waves generated by ThermoAcoustic(TA) lasers. Among various experimental variables, we focused our research on the stack position, stack length, length of the resonance tube and input power

  20. Using assistive technology adaptations to include students with learning disabilities in cooperative learning activities.

    Science.gov (United States)

    Bryant, D P; Bryant, B R

    1998-01-01

    Cooperative learning (CL) is a common instructional arrangement that is used by classroom teachers to foster academic achievement and social acceptance of students with and without learning disabilities. Cooperative learning is appealing to classroom teachers because it can provide an opportunity for more instruction and feedback by peers than can be provided by teachers to individual students who require extra assistance. Recent studies suggest that students with LD may need adaptations during cooperative learning activities. The use of assistive technology adaptations may be necessary to help some students with LD compensate for their specific learning difficulties so that they can engage more readily in cooperative learning activities. A process for integrating technology adaptations into cooperative learning activities is discussed in terms of three components: selecting adaptations, monitoring the use of the adaptations during cooperative learning activities, and evaluating the adaptations' effectiveness. The article concludes with comments regarding barriers to and support systems for technology integration, technology and effective instructional practices, and the need to consider technology adaptations for students who have learning disabilities.

  1. 75 FR 60141 - International Business Machines (IBM), Global Technology Services Delivery Division, Including On...

    Science.gov (United States)

    2010-09-29

    ... 25, 2010, applicable to workers of International Business Machines (IBM), Global Technology Services... hereby issued as follows: All workers of International Business Machines (IBM), Global Technology... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-74,164] International Business...

  2. Technology of surface wastewater purification, including high-rise construction areas

    Science.gov (United States)

    Tsyba, Anna; Skolubovich, Yury

    2018-03-01

    Despite on the improvements in the quality of high-rise construction areas and industrial wastewater treatment, the pollution of water bodies continues to increase. This is due to the organized and unorganized surface untreated sewage entry into the reservoirs. The qualitative analysis of some cities' surface sewage composition is carried out in the work. Based on the published literature review, the characteristic contamination present in surface wastewater was identified. The paper proposes a new technology for the treatment of surface sewage and presents the results of preliminary studies.

  3. Report of study group 3.3 ''LNG and LPG peak shaving and satellite plants''; Rapport du groupe d'etude 3.3 ''usines d'ecretement de pointes et stations satellites GNL et GPL''

    Energy Technology Data Exchange (ETDEWEB)

    Klein Nagelvoort, R.

    2000-07-01

    This report presents a world-wide overview of LNG and LPG Peak Shaving and Satellite Plants, compiled by the study group 3.3 of the International Gas Union. The scope of the work of the study group includes: - LPG peak shavers (LPG + air, N{sub 2}) in gas distribution networks; - LPG peak shavers for start-up and back-up fuel for LNG terminals and power stations; - LNG peak shavers for gas distribution networks; - Small-scale liquefaction plants for distribution to satellites and dedicated consumers (e.g. power generators, chemical plants, trucking companies etc.); - LNG peak shavers as back-up for large consumers; - Alternative liquefaction technologies for LNG and LPG (e.g. refrigeration cycles, supersonic expansion, thermo-acoustic designs); - Alternative storage tank designs for LNG and LPG. The report presents an overview of current installations world-wide and considers the prospects of technological developments with respect to equipment, remote operations and safety constraints. It also includes where possible a review of capital and operating costs, regulations, and an identification of opportunities and trends. The report collates the information available to the study group at the time of the writing, which may explain some heterogeneity in the document. (author)

  4. Modifying the Sleep Treatment Education Program for Students to include technology use (STEPS-TECH): Intervention effects on objective and subjective sleep outcomes.

    Science.gov (United States)

    Barber, Larissa K; Cucalon, Maria S

    2017-12-01

    University students often have sleep issues that arise from poor sleep hygiene practices and technology use patterns. Yet, technology-related behaviors are often neglected in sleep hygiene education. This study examined whether the Sleep Treatment Education Program for Students-modified to include information regarding managing technology use (STEPS-TECH)-helps improve both subjective and objective sleep outcomes among university students. Results of an experimental study among 78 university students showed improvements in objective indicators of sleep quantity (total sleep time) and sleep quality (less awakenings) during the subsequent week for students in the STEPS-TECH intervention group compared to a control group. Exploratory analyses indicated that effects were driven by improvements in weekend days immediately following the intervention. There were also no intervention effects on subjective sleep quality or quantity outcomes. In terms of self-reported behavioral responses to educational content in the intervention, there were no group differences in sleep hygiene practices or technology use before bedtime. However, the intervention group reported less technology use during sleep periods than the control group. These preliminary findings suggest that STEPS-TECH may be a useful educational tool to help improve objective sleep and reduce technology use during sleep periods among university students. Copyright © 2017 John Wiley & Sons, Ltd.

  5. A State-of-the-Art Report on Technologies of Volume Reduction and Self-Disposal for Large Metal Wastes including the Steam Generator of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Lee, Kune Woo; Choi, W. K.; Kim, G. Y.

    2009-06-01

    This report focuses on technologies of volume reduction and self-disposal for large metal wastes including the steam generator of nuclear power plants. This report consists of the cases of treatments and foreign and domestic technologies for steam generator replacement

  6. Estimation of the minimum Prandtl number for binary gas mixtures formed with light helium and certain heavier gases: Application to thermoacoustic refrigerators

    International Nuclear Information System (INIS)

    Campo, Antonio; Papari, Mohammad M.; Abu-Nada, Eiyad

    2011-01-01

    This paper addresses a detailed procedure for the accurate estimation of low Prandtl numbers of selected binary gas mixtures. In this context, helium (He) is the light primary gas and the heavier secondary gases are nitrogen (N 2 ), oxygen (O 2 ), xenon (Xe), carbon dioxide (CO 2 ), methane (CH 4 ), tetrafluoromethane or carbon tetrafluoride (CF 4 ) and sulfur hexafluoride (SF 6 ). The three thermophysical properties forming the Prandtl number of binary gas mixtures Pr mix are heat capacity at constant pressure C p,mix (thermodynamic property), viscosity η mix (transport property) and thermal conductivity λ mix (transport property), which in general depend on temperature T and molar gas composition w. The precise formulas for the calculation of the trio C p,mix , η mix , and λ mix are gathered from various dependable sources. When the set of computed Pr mix values for the seven binary gas mixtures He + N 2 , He + O 2 , He + Xe, He + CO 2 , He + CH 4 , He + CF 4 , He + SF 6 at atmospheric conditions T = 300 K, p = 1 atm is plotted against the molar gas composition w on the w-domain [0,1], the family of Pr mix (w) curves exhibited distinctive concave shapes. In the curves format, all Pr mix (w) curves initiate with Pr ∼ 0.7 at w = 0 (associated with light primary He). Forthwith, each Pr mix (w) curve descends to a unique minimum and thereafter ascend back to Pr ∼ 0.7 at the terminal point w = 1 (connected to heavier secondary gases). Overall, it was found that among the seven binary gas mixtures tested, the He + Xe gas mixture delivered the absolute minimum Prandtl number Pr mix,min = 0.12 at the optimal molar gas composition w opt = 0.975. - Highlights: →Accurate estimation of low Prandtl numbers for some helium-based binary gas mixtures. →The thermophysical properties of the gases are calculated with precise formulas. →The absolute minimum Prandtl number is delivered by the He + Xe binary gas mixture. →Application to experimental thermoacoustic

  7. Smart Antenna Skins, including Conformal Array, MMICs and Applications

    NARCIS (Netherlands)

    Bogaart, F.L.M. van den

    2000-01-01

    Low-cost technologies are presented for future space-borne and airborne SAR systems. These technologies include state-of-the art highly integrated circuits to miniaturise front-end, solutions to lower-cost interconnection technologies, new beamforming aspects and new architectures. The MMICs address

  8. New Nuclear Materials Including Non Metallic Fuel Elements. Vol. I. Proceedings of the Conference on New Nuclear Materials Technology, Including Non Metallic Fuel Elements

    International Nuclear Information System (INIS)

    1963-01-01

    One of the major aims of the International Atomic Energy Agency in furthering the peaceful uses of atomic energy is to encourage the development of economical nuclear power. Certainly, one of the more obvious methods of producing economical nuclear power is the development of economical fuels that can be used at high temperatures for long periods of time, and which have sufficient strength and integrity to operate under these conditions without permitting the release of fission products. In addition it is desirable that after irradiation these new fuels be economically reprocessed to reduce further the cost of the fuel cycle. As nuclear power becomes more and more competitive with conventional power the interest in new and more efficient higher-temperature fuels naturally increases rapidly. For these reasons, the Agency organized a Conference on New Nuclear Materials Technology, Including Non-Metallic Fuel Elements, which was held from 1 to 5 July 1963 at the International Hotel, Prague, with the assistance and co-operation of the Government of the Czechoslovak Socialist Republic. A total of 151 scientists attended, from 23 countries and 4 international organizations. The participants heard and discussed more than 60 scientific papers

  9. Thermally accurate LES of the stability-emission performance of staged gas-turbine combustion; Simulation aux grandes echelles de la combustion etagee dans les turbines a gaz et son interaction stabilite-polluants-thermique

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, P.

    2005-06-15

    Modern gas turbines use turbulent lean partially premixed combustion in order to minimise nitrous oxide (NO{sub X}) emissions while ensuring flashback safety. The Large-Eddy Simulation (LES) of such a device is the goal of this work. Focus is laid on correctly predicting the NO{sub X} emissions, which are influenced by four factors: heat transfer, mixing quality, combustion modelling and thermo-acoustic stability. As NO{sub X} reaction rates are strongly influenced by temperature, heat transfer by radiation and convection is included. Radiation is predicted by a model, which assumes that the gases are optically thin. Convective heat transfer is included via a newly developed and validated wall-function approach based on the logarithmic law of the wall for temperature. An optimised 2-step reduced chemical reaction scheme for lean methane combustion is presented. This scheme is used for the LES in conjunction with an additional third reaction, fitted to produce the same NO{sub X} reaction rates as in the complete reaction mechanism. Turbulence is accounted for with the thickened flame model in a form, which is optimised for changing equivalence ratios and mesh-resolutions. Mixing is essential not only for predicting flame stabilisation, but also for pollutant emissions as NO{sub X} reaction rates depend exponentially on equivalence ratio. Therefore the full burner geometry, including 16 fuel injections is resolved in LES. Additionally, effusion cooling and film cooling is accounted for in a simplified manner. The non-reacting flow is extensively validated with experimental results. As mixture-fraction fluctuations do not only arise from turbulence, but also from thermo-acoustic instabilities, care was taken to provide acoustic boundary conditions that come close to reality. The resulting LES shows a strong thermo-acoustic instability, comparing well with experimental observations. By making the boundaries completely anechoic it is shown that when the instability

  10. The influence of Reynolds numbers on resistance properties of jet pumps

    Energy Technology Data Exchange (ETDEWEB)

    Geng, Q. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Zhou, G. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Li, Q. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); State Key laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry (China)

    2014-01-29

    Jet pumps are widely used in thermoacoustic Stirling heat engines and pulse tube cryocoolers to eliminate the effect of Gedeon streaming. The resistance properties of jet pumps are principally influenced by their structures and flow regimes which are always characterized by Reynolds numbers. In this paper, the jet pump of which cross section contracts abruptly is selected as our research subject. Based on linear thermoacoustic theory, a CFD model is built and the oscillating flow of the working gas is simulated and analyzed with different Reynolds numbers in the jet pump. According to the calculations, the influence of different structures and Reynolds numbers on the resistance properties of the jet pump are analyzed and presented. The results show that Reynolds numbers have a great influence on the resistance properties of jet pumps and some empirical formulas which are widely used are unsuitable for oscillating flow with small Reynolds numbers. This paper provides a more comprehensive understanding on resistance properties of jet pumps with oscillating flow and is significant for the design of jet pumps in practical thermoacoustic engines and refrigerators.

  11. Applications of aerospace technology in industry. A technology transfer profile: Food technology

    Science.gov (United States)

    Murray, D. M.

    1971-01-01

    Food processing and preservation technologies are reviewed, expected technological advances are considered including processing and market factors. NASA contributions to food technology and nutrition are presented with examples of transfer from NASA to industry.

  12. Study of molecular interactions in the mixtures of some primary alcohols with equimolar mixture of 1-propanol and alkylbenzoates at T = 303.15 K

    International Nuclear Information System (INIS)

    Sreehari Sastry, S.; Babu, Shaik; Vishwam, T.; Sie Tiong, Ha

    2014-01-01

    Highlights: • Study of molecular interactions between hydrogen bonded liquid mixtures of alcohols and alkylbenzoates. • Liquids mixtures of some primary alcohols with equimolar mixture of 1-propanol and alkylbenzoates are considered. • Speed of sound, density and viscosity are experimentally determined. • Excess values of different thermo-acoustic parameters are calculated and discussed. • Experimental and theoretical results are compared for speed of sound and viscosity models. -- Abstract: Speed of sound (U), density (ρ) and viscosity (η) values for the equimolar mixtures of (methyl benzoate + 1-propanol) and (ethyl benzoate + 1-propanol) with 1-butanol/1-pentanol including those of pure liquids were measured over the entire mole fraction range at T = 303.15 K. Using these experimentally determined values, various thermo-acoustic parameters such as excess isentropic compressibility (K s E ), excess molar volume (V E ) and excess free length (L f E ), excess Gibbs free energy (ΔG ∗E ) and excess enthalpy (H E ) have been calculated. The excess functions have been fitted to the Redlich–Kister type polynomial equation. The deviations for excess thermo-acoustic parameters have been explained on the basis of the intermolecular interactions present in these binary mixtures. The experimentally determined values of speed of sound have been used to check the applicability of different speed of sound models of Nomoto, Impedance relation, Van Dael and Vangeel, Junjie’s, free length theory and Rao’s relation. Viscosity results have been used to test the applicability of standard viscosity models of Grunberg–Nissan, Hind–Mc Laughlin, Katti–Chaudhary, Heric and Brewer, Frenkel and Tamura and Kurata at various temperatures for the binary liquid systems under study

  13. 78 FR 22911 - HCL America, Inc., a Subsidiary of HCL Technologies Limited, Including On-Site Leased Workers...

    Science.gov (United States)

    2013-04-17

    ... America Inc., a subsidiary of HCL Technologies Limited, Webster, New York (subject firm). Workers are... infrastructure services (hardware/software testing) for clients. The Department's Notice of determination was... subject firm whose unemployment insurance (UI) wages are reported through Segula Technologies The intent...

  14. Space Transportation Technology Workshop: Propulsion Research and Technology

    Science.gov (United States)

    2000-01-01

    This viewgraph presentation gives an overview of the Space Transportation Technology Workshop topics, including Propulsion Research and Technology (PR&T) project level organization, FY 2001 - 2006 project roadmap, points of contact, foundation technologies, auxiliary propulsion technology, PR&T Low Cost Turbo Rocket, and PR&T advanced reusable technologies RBCC test bed.

  15. Utilities and Power - Sector Report. Malaysia: including electricity, gas, water, sewerage, telecommunications and information technology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    This report is one of a series designed to introduce British exporters to the opportunities offered by the Malaysian market. The Seventh Malaysia Plan, covering the five year period, 1996-2000, contains an ambitious menu of infrastructure projects. Total expenditure under the Plan is envisaged at RM450 billion, of which around RM380 billion will be sourced from the private sector. This is an indication of the wealth accumulated within the Malaysian economy. The infrastructure developments identified are designed to take the country towards Vision 2020. These infrastructure developments will continue to make the country highly attractive to foreign investors, who were the catalyst for Malaysia`s explosive growth over the last few years. Malaysian Corporations have also grown rapidly and are becoming international investors and traders in their own right, including in the United Kingdom. As they expand, seeking new markets, they are looking also for partners with whom they can share technology and jointly develop projects. Such companies are often ideal partners for UK companies wishing to enter the Malaysian and Asian market. Malaysia offers opportunities to companies prepared to make the small effort to know and understand the country and its people. This report will assist companies to develop a useful understanding of the market. (author)

  16. Synchronous behaviour of two interacting oscillatory systems undergoing quasiperiodic route to chaos.

    Science.gov (United States)

    Mondal, S; Pawar, S A; Sujith, R I

    2017-10-01

    Thermoacoustic instability, caused by a positive feedback between the unsteady heat release and the acoustic field in a combustor, is a major challenge faced in most practical combustors such as those used in rockets and gas turbines. We employ the synchronization theory for understanding the coupling between the unsteady heat release and the acoustic field of a thermoacoustic system. Interactions between coupled subsystems exhibiting different collective dynamics such as periodic, quasiperiodic, and chaotic oscillations are addressed. Even though synchronization studies have focused on different dynamical states separately, synchronous behaviour of two coupled systems exhibiting a quasiperiodic route to chaos has not been studied. In this study, we report the first experimental observation of different synchronous behaviours between two subsystems of a thermoacoustic system exhibiting such a transition as reported in Kabiraj et al. [Chaos 22, 023129 (2012)]. A rich variety of synchronous behaviours such as phase locking, intermittent phase locking, and phase drifting are observed as the dynamics of such subsystem change. The observed synchronization behaviour is further characterized using phase locking value, correlation coefficient, and relative mean frequency. These measures clearly reveal the boundaries between different states of synchronization.

  17. Pattern-formation under acoustic driving forces

    Science.gov (United States)

    Valverde, Jose Manuel

    2015-07-01

    Chemical and metallurgical processes enhanced by high intensity acoustic waves, thermoacoustic engines and refrigerators, fuel rods in nuclear reactors, heat exchanger tubes, offshore and vibrating structures, solar thermal collectors, acoustic levitators, microfluidic devices, cycling, musical acoustics, blood flow through veins/arteries, hearing in the mammalian ear, carbon nanotube loudspeakers, etc. The evolution of a myriad of processes involving the oscillation of viscous fluids in the presence of solid boundaries is up to a certain extent influenced by acoustic streaming. In addition to the sound field, viscous energy dissipation at the fluid-solid boundary causes a time-independent fluid circulation, which can lead to a significant enhancement of heat, mass and momentum transfer at large oscillation amplitudes. A particularly relevant phenomenon that can be notably affected by acoustic streaming is the promotion of sound waves by temperature gradients or viceversa (thermoacoustics), which is at the basis of potentially efficient and environmental friendly engines and refrigerators that have attracted a renewed interest in the last years. In the present manuscript, historical developments and the underlying basic physics behind acoustic streaming and thermoacoustics are reviewed from an unifying perspective.

  18. Maritime Technology

    DEFF Research Database (Denmark)

    Sørensen, Herman

    1997-01-01

    Elementary introduction to the subject "Maritime Technology".The contents include drawings, sketches and references in English without any supplementary text.......Elementary introduction to the subject "Maritime Technology".The contents include drawings, sketches and references in English without any supplementary text....

  19. Flameless Combustion Workshop

    National Research Council Canada - National Science Library

    Gutmark, Ephraim

    2005-01-01

    .... "Flameless Combustion" is characterized by high stability levels with virtually no thermoacoustic instabilities, very low lean stability limits and therefore extremely low NOx production, efficient...

  20. Development of Lab-to-Fab Production Equipment Across Several Length Scales for Printed Energy Technologies, Including Solar Cells

    DEFF Research Database (Denmark)

    Hösel, Markus; Dam, Henrik Friis; Krebs, Frederik C

    2015-01-01

    We describe and review how the scaling of printed energy technologies not only requires scaling of the input materials but also the machinery used in the processes. The general consensus that ultrafast processing of technologies with large energy capacity can only be realized using roll-to-roll m...

  1. Morgantown Energy Technology Center, technology summary

    International Nuclear Information System (INIS)

    1994-06-01

    This document has been prepared by the DOE Environmental Management (EM) Office of Technology Development (OTD) to highlight its research, development, demonstration, testing, and evaluation activities funded through the Morgantown Energy Technology Center (METC). Technologies and processes described have the potential to enhance DOE's cleanup and waste management efforts, as well as improve US industry's competitiveness in global environmental markets. METC's R ampersand D programs are focused on commercialization of technologies that will be carried out in the private sector. META has solicited two PRDAs for EM. The first, in the area of groundwater and soil technologies, resulted in twenty-one contact awards to private sector and university technology developers. The second PRDA solicited novel decontamination and decommissioning technologies and resulted in eighteen contract awards. In addition to the PRDAs, METC solicited the first EM ROA in 1993. The ROA solicited research in a broad range of EM-related topics including in situ remediation, characterization, sensors, and monitoring technologies, efficient separation technologies, mixed waste treatment technologies, and robotics. This document describes these technology development activities

  2. Technology Estimating: A Process to Determine the Cost and Schedule of Space Technology Research and Development

    Science.gov (United States)

    Cole, Stuart K.; Reeves, John D.; Williams-Byrd, Julie A.; Greenberg, Marc; Comstock, Doug; Olds, John R.; Wallace, Jon; DePasquale, Dominic; Schaffer, Mark

    2013-01-01

    NASA is investing in new technologies that include 14 primary technology roadmap areas, and aeronautics. Understanding the cost for research and development of these technologies and the time it takes to increase the maturity of the technology is important to the support of the ongoing and future NASA missions. Overall, technology estimating may help provide guidance to technology investment strategies to help improve evaluation of technology affordability, and aid in decision support. The research provides a summary of the framework development of a Technology Estimating process where four technology roadmap areas were selected to be studied. The framework includes definition of terms, discussion for narrowing the focus from 14 NASA Technology Roadmap areas to four, and further refinement to include technologies, TRL range of 2 to 6. Included in this paper is a discussion to address the evaluation of 20 unique technology parameters that were initially identified, evaluated and then subsequently reduced for use in characterizing these technologies. A discussion of data acquisition effort and criteria established for data quality are provided. The findings obtained during the research included gaps identified, and a description of a spreadsheet-based estimating tool initiated as a part of the Technology Estimating process.

  3. Emerging technology and ethics

    CERN Document Server

    Wakunuma, Kutoma

    2011-01-01

    This e-book on Emerging Technologies and Ethics includes a collection of essays which explore the future and ethics of emerging information and communication technologies. Articles in the collection include an overview of the legal implications which may be relevant to the ethical aspects of emerging technologies and also ethical issues arising from the mass-take up of mobile technologies.

  4. Rover Technologies

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop and mature rover technologies supporting robotic exploration including rover design, controlling rovers over time delay and for exploring . Technology...

  5. Influence of atomization quality modulation on flame dynamics in a hypergolic rocket engine

    Directory of Open Access Journals (Sweden)

    Moritz Schulze

    2016-09-01

    Full Text Available For the numerical evaluation of the thermoacoustic stability of rocket engines often hybrid methods are applied, which separate the computation of wave propagation in the combustor from the analysis of the flame response to acoustic perturbations. Closure requires a thermoacoustic feedback model which provides the heat release fluctuation in the source term of the employed wave transport equations. The influence of the acoustic fluctuations in the combustion chamber on the heat release fluctuations from the modulation of the atomization of the propellants in a hypergolic upper stage rocket engine is studied. Numerical modeling of a single injector provides the time mean reacting flow field. A network of transfer functions representing all aspects relevant for the feedback model is presented. Analytical models for the injector admittances and for the atomization transfer functions are provided. The dynamics of evaporation and combustion are studied numerically and the numerical results are analyzed. An analytical approximation of the computed flame transfer function is combined with the analytical models for the injector and the atomization quality to derive the feedback model for the wave propagation code. The evaluation of this model on the basis of the Rayleigh index reveals the thermoacoustic driving potential originating from the fluctuating spray quality.

  6. High-speed laser diagnostics for the study of flame dynamics in a lean premixed gas turbine model combustor

    Science.gov (United States)

    Boxx, Isaac; Arndt, Christoph M.; Carter, Campbell D.; Meier, Wolfgang

    2012-03-01

    A series of measurements was taken on two technically premixed, swirl-stabilized methane-air flames (at overall equivalence ratios of ϕ = 0.73 and 0.83) in an optically accessible gas turbine model combustor. The primary diagnostics used were combined planar laser-induced fluorescence of the OH radical and stereoscopic particle image velocimetry (PIV) with simultaneous repetition rates of 10 kHz and a measurement duration of 0.8 s. Also measured were acoustic pulsations and OH chemiluminescence. Analysis revealed strong local periodicity in the thermoacoustically self-excited (or ` noisy') flame (ϕ = 0.73) in the regions of the flow corresponding to the inner shear layer and the jet-inflow. This periodicity appears to be the result of a helical precessing vortex core (PVC) present in that region of the combustor. The PVC has a precession frequency double (at 570 Hz) that of the thermo-acoustic pulsation (at 288 Hz). A comparison of the various data sets and analysis techniques applied to each flame suggests a strong coupling between the PVC and the thermo-acoustic pulsation in the noisy flame. Measurements of the stable (` quiet') flame (ϕ = 0.83) revealed a global fluctuation in both velocity and heat-release around 364 Hz, but no clear evidence of a PVC.

  7. Development of the preparation technology of macroporous sorbent for industrial off-gas treatment including 14C

    International Nuclear Information System (INIS)

    Cho, Il Hoon; Cho, Young Hyun; Park, Guen Il; Kim, In Tae; Kim, June Hyung; Ahn, Byung Kil

    2001-01-01

    For environmental and health effects due to increasing levels of pollution in the atmosphere, it is necessary to develop environmentally sound technologies for the treatment of greenhouse gases (CO 2 , CH 4 , CFC, etc.) and acid gases (SOx, NOx, etc.). Specifically, advanced technology for CO 2 capturing is currently one of the most important environmental issues in worldwide. 14 CO 2 , specially which has been gradually emerging issue in the nuclear facilities, is generated about 330 ppm from the CANDU (Canadian Deuterium Uranium Reactor) nuclear power plant and the DUPIC (Direct Use of spent PWR fuel in CANDU reactors) process which is the process of spent fuel treatment. For this purpose, it is necessary to develop the most efficient treatment technology of CO 2 capture by various lime materials in semi- or dry process, it should be also considering a removal performance, waste recycling and safety of disposal. In order to develop a highly active slaked lime as a sorbent for CO 2 and high temperature desulfurization, macroporous slaked lime is necessarily prepared by modified swelling process and equipment, which was developed under carrying out this project. And also for the optimal removal process of off-gases the removal performance tests of various sorbents and the effects of relative humidity and bed depth on the removal capacity must be considered

  8. Newnes communications technology handbook

    CERN Document Server

    Lewis, Geoff

    1994-01-01

    Newnes Communications Technology Handbook provides a discussion on different topics relevant to communications technology. The book is comprised of 39 chapters that tackle a wide variety of concern in communications technology. The coverage of the text includes technologies, such as analog digital communications systems, radio frequency receiver, and satellite systems. The book also discusses some methods and techniques used in communications technology, including mixer signal processing, modulation and demodulation, and spread spectrum techniques. The text will be of great use to engineers, t

  9. New Nuclear Materials Including Non Metallic Fuel Elements. Vol. II. Proceedings of the Conference on New Nuclear Materials Technology, Including Non Metallic Fuel Elements

    International Nuclear Information System (INIS)

    1963-01-01

    One of the major aims of the International Atomic Energy Agency in furthering the peaceful uses of atomic energy is to encourage the development of economical nuclear power. Certainly, one of the more obvious methods of producing economical nuclear power is the development of economical fuels that can be used at high temperatures for long periods of time, and which have sufficient strength and integrity to operate under these conditions without permitting the release of fission products. In addition it is desirable that after irradiation these new fuels be economically reprocessed to reduce further the cost of the fuel cycle. As nuclear power becomes more and more competitive with conventional power the interest in new and more efficient higher-temperature fuels naturally increases rapidly. For these reasons, the Agency organized a Conference on New Nuclear Materials Technology, Including Non-Metallic Fuel Elements, which was held from 1 to 5 July 1963 at the International Hotel, Prague, with the assistance and co-operation of the Government of the Czechoslovak Socialist Republic. A total of 151 scientists attended, from 23 countries and 4 international organizations. The participants heard and discussed more than 60 scientific papers. The Agency wishes to thank the scientists who attended this Conference for their papers and for many spirited discussions that truly mark a successful meeting. The Agency wishes also to record its gratitude for the assistance and generous hospitality accorded the Conference, the participants and the Agency's staff by the Government of the Czechoslovak Socialist Republic and by the people of Prague. The scientific information contained in these Proceedings should help to quicken the pace of progress in the fabrication of new and m ore economical fuels, and it is hoped that these proceedings will be found useful to all workers in this and related fields

  10. Future Information Technology

    CERN Document Server

    Stojmenovic, Ivan; Choi, Min; Xhafa, Fatos; FutureTech 2013

    2014-01-01

    Future technology information technology stands for all of continuously evolving and converging information technologies, including digital convergence, multimedia convergence, intelligent applications, embedded systems, mobile and wireless communications, bio-inspired computing, grid and cloud computing, semantic web, user experience and HCI, security and trust computing and so on, for satisfying our ever-changing needs. In past twenty five years or so, Information Technology (IT) influenced and changed every aspect of our lives and our cultures. These proceedings foster the dissemination of state-of-the-art research in all future IT areas, including their models, services, and novel applications associated with their utilization.

  11. Projecting technology change to improve space technology planning and systems management

    Science.gov (United States)

    Walk, Steven Robert

    2011-04-01

    Projecting technology performance evolution has been improving over the years. Reliable quantitative forecasting methods have been developed that project the growth, diffusion, and performance of technology in time, including projecting technology substitutions, saturation levels, and performance improvements. These forecasts can be applied at the early stages of space technology planning to better predict available future technology performance, assure the successful selection of technology, and improve technology systems management strategy. Often what is published as a technology forecast is simply scenario planning, usually made by extrapolating current trends into the future, with perhaps some subjective insight added. Typically, the accuracy of such predictions falls rapidly with distance in time. Quantitative technology forecasting (QTF), on the other hand, includes the study of historic data to identify one of or a combination of several recognized universal technology diffusion or substitution patterns. In the same manner that quantitative models of physical phenomena provide excellent predictions of system behavior, so do QTF models provide reliable technological performance trajectories. In practice, a quantitative technology forecast is completed to ascertain with confidence when the projected performance of a technology or system of technologies will occur. Such projections provide reliable time-referenced information when considering cost and performance trade-offs in maintaining, replacing, or migrating a technology, component, or system. This paper introduces various quantitative technology forecasting techniques and illustrates their practical application in space technology and technology systems management.

  12. ACR-700 advanced technologies

    International Nuclear Information System (INIS)

    Tapping, R.L.; Turner, C.W.; Yu, S.K.W.; Olmstead, R.; Speranzini, R.A.

    2004-01-01

    A successful advanced reactor plant will have optimized economics including reduced operating and maintenance costs, improved performance, and enhanced safety. Incorporating improvements based on advanced technologies ensures cost, safety and operational competitiveness of the ACR-700. These advanced technologies include modern configuration management; construction technologies; operational technology for the control centre and information systems for plant monitoring and analysis. This paper summarizes the advanced technologies used to achieve construction and operational improvements to enhance plant economic competitiveness, advances in the operational technology used for reactor control, and presents the development of the Smart CANDU suite of tools and its application to existing operating reactors and to the ACR-700. (author)

  13. Power Technologies Data Book

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, L.

    2002-09-01

    This report, prepared by NREL's Energy Analysis Office, includes up-to-date information on power technologies, including complete technology profiles. The data book also contains charts on electricity restructuring, power technology forecasts and comparisons, electricity supply, electricity capability, electricity generation, electricity demand, prices, economic indicators, environmental indicators, conversion factors, and selected congressional questions and answers.

  14. Speeds of sound and isothermal compressibility of ternary liquid ...

    Indian Academy of Sciences (India)

    Thermo-acoustics Research Lab, Department of Chemistry, University of Allahabad,. Allahabad 211 002, India ... compressibility data of these industrially important organic compounds of ternary and higher liquid ... distillation. Densities and ...

  15. The Agile Rapid Global Combat Support (ARGCS) System: A Cost and Benefit Analysis of Including the ARGCS Technologies in the Acquisition of the Enhanced Consolidated Support System (ECASS)

    National Research Council Canada - National Science Library

    Lund, John N

    2007-01-01

    ...). The ultimate goal of this project is to assist in the analysis of the ARGCS technologies and what benefit they would provide if included in the proposed next generation of Naval Aviation test equipment, currently called the Enhanced Consolidated Automated Support System (ECASS).

  16. Communications technology handbook

    CERN Document Server

    Lewis, Geoff

    2013-01-01

    This is the first point of reference for the communications industries. It offers an introduction to a wide range of topics and concepts encountered in the field of communications technology. Whether you are looking for a simple explanation, or need to go into a subject in more depth, the Communications Technology Handbook provides all the information you need in one single volume.This second edition has been updated to include the latest technology including: Video on DemandWire-less Distribution systemsHigh spee

  17. Including investment risk in large-scale power market models

    DEFF Research Database (Denmark)

    Lemming, Jørgen Kjærgaard; Meibom, P.

    2003-01-01

    Long-term energy market models can be used to examine investments in production technologies, however, with market liberalisation it is crucial that such models include investment risks and investor behaviour. This paper analyses how the effect of investment risk on production technology selection...... can be included in large-scale partial equilibrium models of the power market. The analyses are divided into a part about risk measures appropriate for power market investors and a more technical part about the combination of a risk-adjustment model and a partial-equilibrium model. To illustrate...... the analyses quantitatively, a framework based on an iterative interaction between the equilibrium model and a separate risk-adjustment module was constructed. To illustrate the features of the proposed modelling approach we examined how uncertainty in demand and variable costs affects the optimal choice...

  18. An Introduction to Biometrics Technology: Its Place in Technology Education

    Science.gov (United States)

    Elliott, Stephen J.; Peters, Jerry L.; Rishel, Teresa J.

    2004-01-01

    The increased utilization of biometrics technology in the past few years has contributed to a strong growth pattern as the technology is used in a variety of facilities, including schools. Due to media exposure, students' familiarity with technology will continue to increase proportionately, which will result in an increased curiosity about…

  19. Clean coal technologies in Japan: technological innovation in the coal industry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-12-15

    This brochure reviews the history clean coal technologies (CCT) in Japan and systematically describes the present state of CCT insofar. The brochure contains three parts. Part 1. CCT classifications; Part 2. CCT overview; and Part 3. Future outlook for CCT. The main section is part 2 which includes 1) technologies for coal resources development; 2) coal-fired power generation technologies - combustion technologies and gasification technologies; 3) iron making and general industry technologies; 4) multi-purpose coal utilization technologies - liquefaction technologies, pyrolysis technologies, powdering, fluidization, and co-utilisation technologies, and de-ashing and reforming technologies; 5) Environmental protection technologies - CO{sub 2} recovery technologies; flue gas treatment and gas cleaning technologies, and technologies to effectively use coal has; 6) basic technologies for advanced coal utilization; and 7) co-production systems.

  20. Technology strategy for gas technologies; Technology Target Areas; TTA8 Gas Technology

    Energy Technology Data Exchange (ETDEWEB)

    2008-07-01

    TTA8 - Gas technologies points out the various routes Norway can follow to capitalise on the vast resources of natural gas that will be produced in the years to come by developing a strong technology and competence platform. A broad view is taken for the value creation having as basis the continued gas export from NCS to Europe, but also a strong focus on development of gas resources in other parts of the world. The latter can also be seen as part of international positioning for upstream resources and does also include involvements in projects, and export of technology and products. The TTA has structured the analysis into 3 main areas: Gas transport and processing (pipeline, LNG, other); Gas conversion to fuels, chemicals and materials; CO{sub 2} management. In this report, for each of these areas, scenarios based on a gap analysis are presented. One of the key goals has been to identify pacing and emerging technologies for the next 20 years. Based on this, technologies have been mapped according to importance for future competitiveness and technology ambitions. This also includes primary funding responsibilities (public and/or industry). The road map below reflects the key issues in the proposed strategy. The base level of the figure explains areas that will have to be pursued to maintain Norway's role as a key gas and gas technology provider. The second layer represents near term options and possibilities with a reasonable risk profile that could further enhance the Norwegian position given the resources and drive to further develop this industry. As the top layer we have selected some of our 'dreams', what we may achieve if a progressive approach is followed with a strongly innovation based policy. It is acknowledged by the TTA that Norway cannot be a leading technology player in all aspects of the gas value chain. For some technologies we should be an active player and developer, whilst for other technologies we should become a competent buyer and user. This

  1. Technology strategy for gas technologies; Technology Target Areas; TTA8 Gas Technology

    Energy Technology Data Exchange (ETDEWEB)

    2008-07-01

    TTA8 - Gas technologies points out the various routes Norway can follow to capitalise on the vast resources of natural gas that will be produced in the years to come by developing a strong technology and competence platform. A broad view is taken for the value creation having as basis the continued gas export from NCS to Europe, but also a strong focus on development of gas resources in other parts of the world. The latter can also be seen as part of international positioning for upstream resources and does also include involvements in projects, and export of technology and products. The TTA has structured the analysis into 3 main areas: Gas transport and processing (pipeline, LNG, other); Gas conversion to fuels, chemicals and materials; CO{sub 2} management. In this report, for each of these areas, scenarios based on a gap analysis are presented. One of the key goals has been to identify pacing and emerging technologies for the next 20 years. Based on this, technologies have been mapped according to importance for future competitiveness and technology ambitions. This also includes primary funding responsibilities (public and/or industry). The road map below reflects the key issues in the proposed strategy. The base level of the figure explains areas that will have to be pursued to maintain Norway's role as a key gas and gas technology provider. The second layer represents near term options and possibilities with a reasonable risk profile that could further enhance the Norwegian position given the resources and drive to further develop this industry. As the top layer we have selected some of our 'dreams', what we may achieve if a progressive approach is followed with a strongly innovation based policy. It is acknowledged by the TTA that Norway cannot be a leading technology player in all aspects of the gas value chain. For some technologies we should be an active player and developer, whilst for other technologies we should become a competent buyer

  2. Theme: Emerging Technologies.

    Science.gov (United States)

    Malpiedi, Barbara J.; And Others

    1989-01-01

    Consists of six articles discussing the effect of emerging technologies on agriculture. Specific topics include (1) agriscience programs, (2) the National Conference on Agriscience and Emerging Occupations and Technologies, (3) biotechnology, (4) program improvement through technology, (5) the Agriscience Teacher of the Year program, and (6)…

  3. 75 FR 39044 - Unisys Corporation, Technology Business Segment, Unisys Information Technology Division, Formerly...

    Science.gov (United States)

    2010-07-07

    ..., Technology Business Segment, Unisys Information Technology Division, Formerly Known as BETT, Including... Assistance on April 29, 2010, applicable to workers of Unisys Corporation, Technology Business Segment... employees under the control of the Plymouth, Michigan location of Unisys Corporation, Technology Business...

  4. Information Communication Technology to support and include Blind students in a school for all An Interview study of teachers and students’ experiences with inclusion and ICT support to blind students

    OpenAIRE

    Rony, Mahbubur Rahman

    2017-01-01

    The topic of this is this study is how blind students and teachers experiences Information Communication Technology as a tool to support and include blind students in a school for all. The study investigates how Information and Communication Technologies (ICT) enables blind students to adjust into non-special schools. The research method used to collect data is interview. The goal is to get insight to teachers and students’ experiences with inclusion and ICT as a tool to support blind student...

  5. Development of the preparation technology of macroporous sorbent for industrial off-gas treatment including {sup 14}C

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Il Hoon; Cho, Young Hyun; Park, Guen Il; Kim, In Tae; Kim, June Hyung; Ahn, Byung Kil

    2001-01-01

    For environmental and health effects due to increasing levels of pollution in the atmosphere, it is necessary to develop environmentally sound technologies for the treatment of greenhouse gases (CO{sub 2}, CH{sub 4}, CFC, etc.) and acid gases (SOx, NOx, etc.). Specifically, advanced technology for CO{sub 2} capturing is currently one of the most important environmental issues in worldwide. {sup 14}CO{sub 2}, specially which has been gradually emerging issue in the nuclear facilities, is generated about 330 ppm from the CANDU (Canadian Deuterium Uranium Reactor) nuclear power plant and the DUPIC (Direct Use of spent PWR fuel in CANDU reactors) process which is the process of spent fuel treatment. For this purpose, it is necessary to develop the most efficient treatment technology of CO{sub 2} capture by various lime materials in semi- or dry process, it should be also considering a removal performance, waste recycling and safety of disposal. In order to develop a highly active slaked lime as a sorbent for CO{sub 2} and high temperature desulfurization, macroporous slaked lime is necessarily prepared by modified swelling process and equipment, which was developed under carrying out this project. And also for the optimal removal process of off-gases the removal performance tests of various sorbents and the effects of relative humidity and bed depth on the removal capacity must be considered.

  6. Information technology equipment cooling method

    Science.gov (United States)

    Schultz, Mark D.

    2015-10-20

    According to one embodiment, a system for removing heat from a rack of information technology equipment may include a sidecar indoor air to liquid heat exchanger that cools air utilized by the rack of information technology equipment to cool the rack of information technology equipment. The system may also include a liquid to liquid heat exchanger and an outdoor heat exchanger. The system may further include configurable pathways to connect and control fluid flow through the sidecar heat exchanger, the liquid to liquid heat exchanger, the rack of information technology equipment, and the outdoor heat exchanger based upon ambient temperature and/or ambient humidity to remove heat generated by the rack of information technology equipment.

  7. Teaching with Technology

    Science.gov (United States)

    Attard, Catherine

    2011-01-01

    New technologies continue to change every aspect of home, life and work: the way people communicate, calculate, analyse, shop, make presentations and socialise. "The Australian Curriculum" acknowledges the importance of teaching and learning with technology by including the use of information and communication technology (ICT) as one of…

  8. Internetworking technological foundations and applications

    CERN Document Server

    Meinel, Christoph

    2013-01-01

    This book is supposed to serve as a comprehensive and instructive guide through the new world of digital communication. On the physical layer optical and electrical cabling technology are described as well as wireless communication technologies. On the data link layer local area networks (LANs) are introduced together with the most popular LAN technologies such as Ethernet, Token Ring, FDDI, and ATM as well as wireless LAN technologies including IEEE 802.x, Bluetooth, or ZigBee. A wide range of WAN technologies are covered including contemporary high speed technologies like PDH and SDH up to h

  9. Magnetic fusion technology

    CERN Document Server

    Dolan, Thomas J

    2014-01-01

    Magnetic Fusion Technology describes the technologies that are required for successful development of nuclear fusion power plants using strong magnetic fields. These technologies include: ? magnet systems, ? plasma heating systems, ? control systems, ? energy conversion systems, ? advanced materials development, ? vacuum systems, ? cryogenic systems, ? plasma diagnostics, ? safety systems, and ? power plant design studies. Magnetic Fusion Technology will be useful to students and to specialists working in energy research.

  10. Technology roadmaps

    Energy Technology Data Exchange (ETDEWEB)

    Pearson, B. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Energy Technology Centre

    2003-07-01

    The purpose of a technology road map is to define the state of a current technology, relevant market issues, and future market needs; to develop a plan that industry can follow to provide these new products and services; and to map technology pathways and performance goals for bringing these products and services to market. The three stages (planning, implementation, and reviewing and updating), benefits, and status of the Clean Coal Technology Roadmap are outlined. Action Plan 2000, a $1.7 million 2000 Climate Change Technology and Innovation Program, which uses the technology roadmapping process, is described. The members of the management steering committee for the Clean Coal Technology Roadmap are listed. A flowsheet showing activities until November 2004, when the final clean coal road map is due, is included.

  11. Emerging Technological Risk Underpinning the Risk of Technology Innovation

    CERN Document Server

    Anderson, Stuart

    2012-01-01

    Classes of socio-technical hazards allow a characterization of the risk in technology innovation and clarify the mechanisms underpinning emergent technological risk. Emerging Technological Risk provides an interdisciplinary account of risk in socio-technical systems including hazards which highlight: ·         How technological risk crosses organizational boundaries, ·         How technological trajectories and evolution develop from resolving tensions emerging between social aspects of organisations and technologies and ·         How social behaviour shapes, and is shaped by, technology. Addressing an audience from a range of academic and professional backgrounds, Emerging Technological Risk is a key source for those who wish to benefit from a detail and methodical exposure to multiple perspectives on technological risk. By providing a synthesis of recent work on risk that captures the complex mechanisms that characterize the emergence of risk in technology innovation, Emerging Tec...

  12. Building Technologies Program Multi-Year Program Plan Technology Validation and Market Introduction 2008

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2008-01-01

    Building Technologies Program Multi-Year Program Plan 2008 for technology validation and market introduction, including ENERGY STAR, building energy codes, technology transfer application centers, commercial lighting initiative, EnergySmart Schools, EnergySmar

  13. Persuasive Technology

    DEFF Research Database (Denmark)

    This book constitutes the proceedings of the 5th International Conference on Persuasive Technology, PERSUASIVE 2010, held in Copenhagen Denmark in June 2010. The 25 papers presented were carefully reviewed and selected from 80 submissions. In addition three keynote papers are included in this vol......This book constitutes the proceedings of the 5th International Conference on Persuasive Technology, PERSUASIVE 2010, held in Copenhagen Denmark in June 2010. The 25 papers presented were carefully reviewed and selected from 80 submissions. In addition three keynote papers are included...... in this volume. The topics covered are emotions and user experience, ambient persuasive systems, persuasive design, persuasion profiles, designing for health, psychology of persuasion, embodied and conversational agents, economic incentives, and future directions for persuasive technology....

  14. Alpha-Stream Convertor

    Science.gov (United States)

    Dyson, Jr., Rodger William (Inventor); Bruder, Geoffrey Adam (Inventor)

    2015-01-01

    A thermo-acoustic engine and/or cooler is provided and includes an elongated tubular body, multiple regenerators disposed within the body, multiple heat exchangers disposed within the body, where at least one heat exchanger is disposed adjacent to each of the multiple regenerators, multiple transducers axially disposed at each end of the body, and an acoustic wave source generating acoustic waves. At least one of the acoustic waves is amplified by one of the regenerators and at least another acoustic wave is amplified by a second one of regenerators.

  15. Challenges for Life Support Systems in Space Environments, Including Food Production

    Science.gov (United States)

    Wheeler, Raymond M.

    2012-01-01

    Environmental Control and Life Support Systems (ECLSS) refer to the technologies needed to sustain human life in space environments. Histor ically these technologies have focused on providing a breathable atmo sphere, clean water, food, managing wastes, and the associated monitoring capabilities. Depending on the space agency or program, ELCSS has sometimes expanded to include other aspects of managing space enviro nments, such as thermal control, radiation protection, fire detection I suppression, and habitat design. Other times, testing and providing these latter technologies have been associated with the vehicle engi neering. The choice of ECLSS technologies is typically driven by the mission profile and their associated costs and reliabilities. These co sts are largely defined by the mass, volume, power, and crew time req uirements. For missions close to Earth, e.g., low-Earth orbit flights, stowage and resupply of food, some 0 2, and some water are often the most cost effective option. But as missions venture further into spa ce, e.g., transit missions to Mars or asteroids, or surface missions to Moon or Mars, the supply line economics change and the need to clos e the loop on life support consumables increases. These are often ref erred to as closed loop or regenerative life support systems. Regardless of the technologies, the systems must be capable of operating in a space environment, which could include micro to fractional g setting s, high radiation levels, and tightly closed atmospheres, including perhaps reduced cabin pressures. Food production using photosynthetic o rganisms such as plants by nature also provides atmospheric regenerat ion (e.g., CO2 removal and reduction, and 0 2 production), yet to date such "bioregenerative" technologies have not been used due largely t o the high power requirements for lighting. A likely first step in te sting bioregenerative capabilities will involve production of small a mounts of fresh foods to supplement to crew

  16. Workplace Demographics and Technology: Challenges and Opportunities to the Campus Mission Including the Top Facilities Issues. APPA Thought Leaders 2011

    Science.gov (United States)

    APPA: Association of Higher Education Facilities Officers, 2011

    2011-01-01

    It is not unusual in higher education circles to talk about issues affecting the campus. Experts might write about how shifting demographics are changing the campus, or say technology is becoming more pervasive on campus. The campus itself evolves alongside pedagogical practices, technological innovations, student needs, and the mission of the…

  17. Information technology equipment cooling system

    Science.gov (United States)

    Schultz, Mark D.

    2014-06-10

    According to one embodiment, a system for removing heat from a rack of information technology equipment may include a sidecar indoor air to liquid heat exchanger that cools warm air generated by the rack of information technology equipment. The system may also include a liquid to liquid heat exchanger and an outdoor heat exchanger. The system may further include configurable pathways to connect and control fluid flow through the sidecar heat exchanger, the liquid to liquid heat exchanger, the rack of information technology equipment, and the outdoor heat exchanger based upon ambient temperature and/or ambient humidity to remove heat from the rack of information technology equipment.

  18. NASA Technology Transfer System

    Science.gov (United States)

    Tran, Peter B.; Okimura, Takeshi

    2017-01-01

    NTTS is the IT infrastructure for the Agency's Technology Transfer (T2) program containing 60,000+ technology portfolio supporting all ten NASA field centers and HQ. It is the enterprise IT system for facilitating the Agency's technology transfer process, which includes reporting of new technologies (e.g., technology invention disclosures NF1679), protecting intellectual properties (e.g., patents), and commercializing technologies through various technology licenses, software releases, spinoffs, and success stories using custom built workflow, reporting, data consolidation, integration, and search engines.

  19. Technology in Education

    Science.gov (United States)

    Roden, Kasi

    2011-01-01

    This paper was written to support a position on using technology in education. The purpose of this study was to support the use of technology in education by synthesizing previous research. A variety of sources including books and journal articles were studied in order to compile an overview of the benefits of using technology in elementary,…

  20. Geothermal energy technology

    Energy Technology Data Exchange (ETDEWEB)

    1977-01-01

    Geothermal energy research and development by the Sunshine Project is subdivided into five major categories: exploration and exploitation technology, hot-water power generation technology, volcanic power generation technology, environmental conservation and multi-use technology, and equipment materials research. The programs are being carried out by various National Research Institutes, universities, and private industry. During 1976 and 1977, studies were made of the extent of resources, reservoir structure, ground water movement, and neotectonics at the Onikobe and Hachimantai geothermal fields. Studies to be performed in the near future include the use of new prospecting methods, including artificial magnetotellurics, heat balance calculation, brightspot techniques, and remote sensing, as well as laboratory studies of the physical, mechanical, and chemical properties of rock. Studies are continuing in the areas of ore formation in geothermal environments, hot-dry-rock drilling and fracturing, large scale prospecting technology, high temperature-pressure drilling muds and well cements, and arsenic removal techniques.

  1. Survey of the situation of technology succession. Databases of articles including in industrial technology museums; Gijutsu keisho jokyo chosa. Sangyo gijutsu hakubutsukan shuzohin D.B. hen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    To promote the succession of history of and the creative use of industrial science technologies, the paper made lists and databases of the articles of industrial technology museums and material halls in Japan. Record/preservation and collection/systematization of history of the industrial technology is useful for forming bases necessary for promotion of future research/development and international contribution. Museums and material halls are the fields for making comprehensive and practical activities. The data were made as one of the basic databases as the first step for promoting activities for examining the technical succession situation in a long term range continuously and systematically. In the classification of the data, the energy relation was divided into electric power, nuclear power, oil, coal, gas and energy in general. Others were classified into metal/mine, electricity/electronics/communication, chemistry/food, ship building/heavy machinery, printing/precision instrument, and textile/spinning. Moreover, the traffic relation was classified into railroad, automobiles/two-wheeled vehicles, airline/space, and ships. Items were also set of life relation, civil engineering/architecture, and general. The total number of the museums for the survey reached 208.

  2. Copper Cable Recycling Technology. Innovative Technology Summary Report

    International Nuclear Information System (INIS)

    2001-01-01

    The United States Department of Energy (DOE) continually seeks safer and more cost-effective technologies for use in deactivation and decommissioning (D and D) of nuclear facilities. The Deactivation and Decommissioning Focus Area (DDFA) of the DOE's Office of Science and Technology (OST) sponsors large-scale demonstration and deployment projects (LSDDPs). At these LSDDPs, developers and vendors of improved or innovative technologies showcase products that are potentially beneficial to the DOE's projects and to others in the D and D community. Benefits sought include decreased health and safety risks to personnel and the environment, increased productivity, and decreased costs of operation. The Idaho National Engineering and Environmental Laboratory (INEEL) generated a list of statements defining specific needs and problems where improved technology could be incorporated into ongoing D and D tasks. One such need is to reduce the volume of waste copper wire and cable generated by D and D. Deactivation and decommissioning activities of nuclear facilities generates hundreds of tons of contaminated copper cable, which are sent to radioactive waste disposal sites. The Copper Cable Recycling Technology separates the clean copper from contaminated insulation and dust materials in these cables. The recovered copper can then be reclaimed and, more importantly, landfill disposal volumes can be reduced. The existing baseline technology for disposing radioactively contaminated cables is to package the cables in wooden storage boxes and dispose of the cables in radioactive waste disposal sites. The Copper Cable Recycling Technology is applicable to facility decommissioning projects at many Department of Energy (DOE) nuclear facilities and commercial nuclear power plants undergoing decommissioning activities. The INEEL Copper Cable Recycling Technology Demonstration investigated the effectiveness and efficiency to recycle 13.5 tons of copper cable. To determine the effectiveness

  3. IT-BT convergence technology

    International Nuclear Information System (INIS)

    2012-12-01

    This book explains IT-BT convergence technology as the future technology, which includes a prolog, easy IT-BT convergence technology that has infinite potentials for new value, policy of IT-BT convergence technology showing the potential of smart Korea, IT-BT convergence opening happy future, for the new future of IT powerful nation Korea with IT-BT convergence technology and an epilogue. This book reveals the conception, policy, performance and future of IT-BT convergence technology.

  4. Relations between the technological standards and technological appropriation

    Directory of Open Access Journals (Sweden)

    Carlos Alberto PRADO GUERRERO

    2010-06-01

    Full Text Available The objective of this study is to analyze the educational practices of using Blackboard in blended learning environments with students of higher education to understand the relationship between technological appropriation and standards of educational technology. To achieve that goal, the following research question was raised: ¿To what extent are the standards of education technology with the appropriation of technology in blended learning environments in higher educa­tion related? The contextual framework of this work includes the following topics: the institution, teaching, teachers and students. The design methodology that was used is of a correlation type. Correlations were carried out to determine the frequency and level in the technological standards as well as the appropriation of technology. In the comparison of the results obtained by the students, the teachers and the platform; we found that students in the school study showed a high degree of technology ownership and this was the same for the performance shown on the technological standards. It was established that teachers play a key role in developing the techno­logical appropriation of students and performance in technology standards.

  5. Advanced Manufacturing Technologies

    Science.gov (United States)

    Fikes, John

    2016-01-01

    Advanced Manufacturing Technologies (AMT) is developing and maturing innovative and advanced manufacturing technologies that will enable more capable and lower-cost spacecraft, launch vehicles and infrastructure to enable exploration missions. The technologies will utilize cutting edge materials and emerging capabilities including metallic processes, additive manufacturing, composites, and digital manufacturing. The AMT project supports the National Manufacturing Initiative involving collaboration with other government agencies.

  6. 75 FR 67770 - Sara Lee Corporation Including On-Site Leased Workers From EDS, Hewitt Packard, Sapphire...

    Science.gov (United States)

    2010-11-03

    ..., Deductions, Collections, Call Center, Information Technology, Accounts Payable, General Accounts, Financial... this certification to include workers providing shared financial and information technology services at..., Deductions, Collections, Call Center, Information Technology, Accounts Payable, General Accounts, Financial...

  7. Soulful Technologies

    DEFF Research Database (Denmark)

    Fausing, Bent

    2010-01-01

    Samsung introduced in 2008 a mobile phone called "Soul" made with a human touch and including itself a "magic touch". Through the analysis of a Nokia mobile phone TV-commercials I want to examine the function and form of digital technology in everyday images. The mobile phone and its digital camera...... and other devices are depicted by everyday aesthetics as capable of producing a unique human presence and interaction. The medium, the technology is a necessary helper of this very special and lost humanity. Without the technology, no special humanity, no soul - such is the prophecy. This personification...... or anthropomorphism is important for the branding of new technology. Technology is seen as creating a techno-transcendence towards a more qualified humanity which is in contact with fundamental human values like intuition, vision, and sensing; all the qualities that technology, industrialization, and rationalization...

  8. Sodium technology handbook

    International Nuclear Information System (INIS)

    2005-09-01

    This document was published as a textbook for the education and training of personnel working for operations and maintenances of sodium facilities including FBR plants and those engaged in R and D activities related to sodium technology. This handbook covers the following technical areas. Properties of sodium. Compatibilities of sodium with materials. Thermalhydraulics and structural integrity. Sodium systems and components. Sodium instrumentations. Sodium handling technology. Sodium related accident evaluation and countermeasures for FBRs. Operation, maintenance and repair technology of sodium facilities. Safety measures related to sodium. Laws, regulations and internal rules related to sodium. The plannings and discussions of the handbook were made in the Sodium Technology Education Committee organized in O-arai Engineering Center consisting of the representatives of the related departments including Tsuruga headquarters. Experts in various departments participated in writing individual technical subjects. (author)

  9. Focus on Technologies: Worry or Technology?

    Directory of Open Access Journals (Sweden)

    Saulius Kanišauskas

    2015-10-01

    Full Text Available The paper analyses different attitudes towards technologies in contemporary philosophical discourses. It points out that classical notion of technology formulated by Martin Heidegger seems to be more and more often questioned and even forgotten. As a result, it is being replaced by the theory of determinism, according to which the change of technologies determines the changes in social systems, the human being including. This happens this way and not vice versa. Nowadays technē, or “technika” (in English: technology is mostly understood in the instrumental meaning or in the meaning of power. It is considered to be a powerful means, tool or mechanism to influence, change, control and manipulate human consciousness and human feelings. Despite the fact that technologies have already been tamed, the problem of huge responsibility for using and developing them arises. It is questioned whether the increasing society’s attention to modern technologies is not a particular “technology” of the postmodern capitalism to manipulate social consciousness. In parallel with “yes” answer to this question, Albert Borgmann’s idea that the causes of technological development have an ontological dimension, i.e. the causes are rooted in the nature of human beings themselves and their desire to adore own creativity, is discussed. Thus, it becomes necessary to probe deeper into the nature of creativity.

  10. Insertion of marble waste in the production chain of glass wool; Insercao do residuo de marmore na cadeia produtiva da la de vidro

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, G.F.; Alves, J.O.; Espinosa, D.C.R.; Tenorio, J.A.S., E-mail: girleyf@gmail.co [Universidade de Sao Paulo (USP), SP (Brazil). Escola Politecnica. Dept. de Engenharia Metalurgica e de Materiais

    2010-07-01

    The work aimed the study of the recycle of the waste from marble cutting, aiming the reuse as partial raw material in the production of glass wool. Glass wool are materials with chemical and mechanical resistance, durability and lightness, and also important thermo-acoustic properties. A mixture of the waste with chemical additives was melted in a laboratory electric furnace using temperature of 1450 deg C. The melted material was directly poured in a water-filled recipient aiming the rapidly cooling. Samples of the produced material were characterized by XRD, SEM and DTA. The results showed that the residue from marble cutting can be inserted into the productive chain of glass wool, providing a decrease in the extraction of mineral resources, a profitable destination for this waste, and a economy for the companies producer of thermo-acoustic insulators. (author)

  11. Insertion of marble waste in the production chain of glass wool

    International Nuclear Information System (INIS)

    Rodrigues, G.F.; Alves, J.O.; Espinosa, D.C.R.; Tenorio, J.A.S.

    2010-01-01

    The work aimed the study of the recycle of the waste from marble cutting, aiming the reuse as partial raw material in the production of glass wool. Glass wool are materials with chemical and mechanical resistance, durability and lightness, and also important thermo-acoustic properties. A mixture of the waste with chemical additives was melted in a laboratory electric furnace using temperature of 1450 deg C. The melted material was directly poured in a water-filled recipient aiming the rapidly cooling. Samples of the produced material were characterized by XRD, SEM and DTA. The results showed that the residue from marble cutting can be inserted into the productive chain of glass wool, providing a decrease in the extraction of mineral resources, a profitable destination for this waste, and a economy for the companies producer of thermo-acoustic insulators. (author)

  12. Acoustic cryocooler

    International Nuclear Information System (INIS)

    Swift, G.W.; Martin, R.A.; Radebaugh, R.

    1990-01-01

    This patent describes an acoustic cryocooler with no moving parts is formed from a thermoacoustic driver (TAD) driving a pulse tube refrigerator (PTR) through a standing wave tube. Thermoacoustic elements in the TAD are spaced apart a distance effect to accommodate the increased thermal penetration length arising from the relatively low TAD operating frequency in the range of 15--60 Hz. At these low operating frequencies, a long tube is required to support the standing wave. The tube may be coiled to reduce the overall length of the cryocooler. One or two PTR's are located on the standing wave tube adjacent antinodes in the standing wave to be driven by the standing wave pressure oscillations. It is predicted that a heat input of 1000 W at 1000 K will maintain a cooling load of 5 W at 80 K

  13. Managing Technology Is Different.

    Science.gov (United States)

    Levinson, Eliot; Grohe, Barbara

    2002-01-01

    Discusses methods that school superintendents can use to manage technology issues in their schools beyond traditional delegation. Highlights include participation more than delegation to a technology coordinator; identifying the right problems; determining what to make and what to buy; and the need for continual technology funding. (LRW)

  14. HTGR technology development: status and direction

    International Nuclear Information System (INIS)

    Kasten, P.R.

    1982-01-01

    During the last two years there has been an extensive and comprehensive effort expended primarily by General Atomic (GA) in generating a revised technology development plan. Oak Ridge National Laboratory (ORNL) has assisted in this effort, primarily through its interactions over the past years in working together with GA in technology development, but also through detailed review of the initial versions of the technology development plan as prepared by GA. The plan covers Fuel Technology, Materials Technology (including metals, graphite, and ceramics), Plant Technology (including methods, safety, structures, systems, heat exchangers, control and electrical, and mechanical), and Component Design Verification and Support areas

  15. Technological Literacy and Human Cloning. Resources in Technology.

    Science.gov (United States)

    Baird, Steven L.

    2002-01-01

    Discusses how technology educators can deal with advances in human genetics, specifically, cloning. Includes a definition and history of cloning, discusses its benefits, and looks at social concerns and arguments for and against human cloning. Includes classroom activities and websites. (Contains 10 references.) (JOW)

  16. Stability of split Stirling refrigerators

    NARCIS (Netherlands)

    Waele, de A.T.A.M.; Liang, W.

    2009-01-01

    In many thermal systems spontaneous mechanical oscillations are generated under the influence of large temperature gradients. Well-known examples are Taconis oscillations in liquid-helium cryostats and oscillations in thermoacoustic systems. In split Stirling refrigerators the compressor and the

  17. Moralizing Food Technology

    DEFF Research Database (Denmark)

    Coff, Christian Eyde

    2015-01-01

    Food technologies are common on many levels in society and used by both food professionals and consumers. Food technologies are not neutral. They inform and shape the behaviour of people. This paper presents a theoretical framework for analysing the mediating role of food technology and its...... influence on food ethics. Post-phenomenology and the idea of a technologically mediated morality are central theoretical approaches. Four elements are included in the analytical framework: perception, interpretation, intentionality, and mediated morality. The framework is applied to two cases; food safety...

  18. Technology Roadmaps: Cement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    To support its roadmap work focusing on key technologies for emissions reductions, the International Energy Agency (IEA) also investigated one particular industry: cement. Cement production includes technologies that are both specific to this industry and those that are shared with other industries (e.g., grinding, fuel preparation, combustion, crushing, transport). An industry specific roadmap provides an effective mechanism to bring together several technology options. It outlines the potential for technological advancement for emissions reductions in one industry, as well as potential cross-industry collaboration.

  19. Enhancing Literacy Skills through Technology.

    Science.gov (United States)

    Sistek-Chandler, Cynthia

    2003-01-01

    Discusses how to use technology to enhance literacy skills. Highlights include defining literacy, including information literacy; research to support reading and writing instruction; literacy software; thinking skills; organizational strategies for writing and reading; how technology can individualize literacy instruction; and a new genre of…

  20. Technology '90

    International Nuclear Information System (INIS)

    1991-01-01

    The US Department of Energy (DOE) laboratories have a long history of excellence in performing research and development in a number of areas, including the basic sciences, applied-energy technology, and weapons-related technology. Although technology transfer has always been an element of DOE and laboratory activities, it has received increasing emphasis in recent years as US industrial competitiveness has eroded and efforts have increased to better utilize the research and development resources the laboratories provide. This document, Technology '90, is the latest in a series that is intended to communicate some of the many opportunities available for US industry and universities to work with the DOE and its laboratories in the vital activity of improving technology transfer to meet national needs. Technology '90 is divided into three sections: Overview, Technologies, and Laboratories. The Overview section describes the activities and accomplishments of the DOE research and development program offices. The Technologies section provides descriptions of new technologies developed at the DOE laboratories. The Laboratories section presents information on the missions, programs, and facilities of each laboratory, along with a name and telephone number of a technology transfer contact for additional information. Separate papers were prepared for appropriate sections of this report

  1. Acoustic pressure oscillations induced by confined turbulent premixed natural glas flames

    NARCIS (Netherlands)

    van Kampen, J.F.

    2006-01-01

    The present study is concerned with the development and validation of efientt numerical algorithms to check combustion systems for their sensitivity to thermoacoustic instabilities. For this purpose, a good acoustic model is needed. Since the acoustics in combustion systems are essentially

  2. Imaging Apparatus And Method

    NARCIS (Netherlands)

    Manohar, Srirang; van Leeuwen, A.G.J.M.

    2010-01-01

    A thermoacoustic imaging apparatus comprises an electromagnetic radiation source configured to irradiate a sample area and an acoustic signal detection probe arrangement for detecting acoustic signals. A radiation responsive acoustic signal generator is added outside the sample area. The detection

  3. IMAGING APPARATUS AND METHOD

    NARCIS (Netherlands)

    Manohar, Srirang; van Leeuwen, A.G.J.M.

    2008-01-01

    A thermoacoustic imaging apparatus comprises an electromagnetic radiation source configured to irradiate a sample area and an acoustic signal detection probe arrangement for detecting acoustic signals. A radiation responsive acoustic signal generator is added outside the sample area. The detection

  4. Subwoofer and nanotube butterfly acoustic flame extinction

    NARCIS (Netherlands)

    Aliev, Ali E.; Mayo, Nathanael K.; Baughman, Ray H.; Mills, Brent T.; Habtour, Ed

    2017-01-01

    Nonchemical flame control using acoustic waves from a subwoofer and a lightweight carbon nanotube thermoacoustic projector was demonstrated. The intent was to manipulate flame intensity, direction and propagation. The mechanisms of flame suppression using low frequency acoustic waves were discussed.

  5. Thermal and fluid dynamic analysis of partially premixed turbulent combustion driven by thermo acoustic effects

    NARCIS (Netherlands)

    Shahi, Mina; Kok, Jacobus B.W.; Pozarlik, Artur Krzysztof; Sponfeldner, Thomas; Malcolm, M.J.; Pawelczyk, M.; Paosawatyangyong, B.

    2013-01-01

    Thermo-acoustic instability can be caused by the feedback mechanism between unsteady heat release, acoustic oscillations and flow perturbations. In a gas turbine combustor limit cycles of pressure oscillations at elevated temperatures generated by the unstable combustion process enhance the

  6. The Next Technology Revolution - Nano Electronic Technology

    Science.gov (United States)

    Turlik, Iwona

    2004-03-01

    Nanotechnology is a revolutionary engine that will engender enormous changes in a vast majority of today's industries and markets, while potentially creating whole new industries. The impact of nanotechnology is particularly significant in the electronics industry, which is constantly driven by the need for higher performance, increased functionality, smaller size and lower cost. Nanotechnology can influence many of the hundreds of components that are typically assembled to manufacture modern electronic devices. Motorola manufactures electronics for a wide range of industries and communication products. In this presentation, the typical components of a cellular phone are outlined and technology requirements for future products, the customer benefits, and the potential impact of nanotechnology on many of the components are discussed. Technology needs include reliable materials supply, processes for high volume production, experimental and simulation tools, etc. For example, even routine procedures such as failure characterization may require the development of new tools for investigating nano-scale phenomena. Business needs include the development of an effective, high volume supply chain for nano-materials and devices, disruptive product platforms, and visible performance impact on the end consumer. An equally significant long-term industry need is the availability of science and engineering graduates with a multidisciplinary focus and a deep understanding of the fundamentals of nano-technology, that can harness the technology to create revolutionary products.

  7. Information Technology Budgets and Costs: Do You Know What Your Information Technology Costs Each Year?

    Science.gov (United States)

    Dugan, Robert E.

    2002-01-01

    Discusses yearly information technology costs for academic libraries. Topics include transformation and modernization activities that affect prices and budgeting; a cost model for information technologies; life cycle costs, including initial costs and recurring costs; cost benchmarks; and examples of pressures concerning cost accountability. (LRW)

  8. Energy and technology review

    International Nuclear Information System (INIS)

    Quirk, W.J.; Bookless, W.A.

    1994-05-01

    The Lawrence Livermore National Laboratory, operated by the University of California for the United States Department of Energy, was established in 1952 to do research on nuclear weapons and magnetic fusion energy. Since then, in response to new national needs, we have added other major programs, including technology transfer, laser science (fusion, isotope separation, materials processing), biology and biotechnology, environmental research and remediation, arms control and nonproliferation, advanced defense technology, and applied energy technology. These programs, in turn, require research in basic scientific disciplines, including chemistry and materials science, computing science and technology, engineering, and physics. The Laboratory also carries out a variety of projects for other federal agencies. Energy and Technology Review is published monthly to report on unclassified work in all our programs. This issue reviews work performed in the areas of modified retoring for waste treatment and underground stripping to remove contamination

  9. Visible Parts, Invisible Whole: Swedish Technology Student Teachers' Conceptions about Technological Systems

    Science.gov (United States)

    Hallström, Jonas; Klasander, Claes

    2017-01-01

    Technological systems are included as a component of national technology curricula and standards for primary and secondary education as well as corresponding teacher education around the world. Little is known, however, of how pupils, students, and teachers conceive of technological systems. In this article we report on a study investigating…

  10. Educational Technology: Integration?

    Science.gov (United States)

    Christensen, Dean L.; Tennyson, Robert D.

    This paper presents a perspective of the current state of technology-assisted instruction integrating computer language, artificial intelligence (AI), and a review of cognitive science applied to instruction. The following topics are briefly discussed: (1) the language of instructional technology, i.e., programming languages, including authoring…

  11. Office of Technology Development integrated program for development of in situ remediation technologies

    International Nuclear Information System (INIS)

    Peterson, M.

    1992-08-01

    The Department of Energy's Office of Technology Development has instituted an integrated program focused on development of in situ remediation technologies. The development of in situ remediation technologies will focus on five problem groups: buried waste, contaminated soils, contaminated groundwater, containerized wastes and underground detonation sites. The contaminants that will be included in the development program are volatile and non volatile organics, radionuclides, inorganics and highly explosive materials as well as mixtures of these contaminants. The In Situ Remediation Integrated Program (ISR IP) has defined the fiscal year 1993 research and development technology areas for focusing activities, and they are described in this paper. These R ampersand D topical areas include: nonbiological in situ treatment, in situ bioremediation, electrokinetics, and in situ containment

  12. Human Technology and Human Affects

    DEFF Research Database (Denmark)

    Fausing, Bent

    2009-01-01

    Human Technology and Human Affects  This year Samsung introduced a mobile phone with "Soul". It was made with a human touch and included itself a magical touch. Which function does technology and affects get in everyday aesthetics like this, its images and interactions included this presentation...... will ask and try to answer. The mobile phone and its devices are depicted as being able to make a unique human presence, interaction, and affect. The medium, the technology is a necessary helper to get towards this very special and lost humanity. Without the technology, no special humanity - soul....... The paper will investigate how technology, humanity, affects, and synaesthesia are presented and combined with examples from everyday aesthetics, e.g. early computer tv-commercial, net-commercial for mobile phones. Technology and affects point, is the conclusion, towards a forgotten pre-human and not he...

  13. 49 CFR 350.213 - What must a State CVSP include?

    Science.gov (United States)

    2010-10-01

    ... include education, enforcement, legislation, use of technology and improvements to safety infrastructure... activities affecting the transportation of controlled substances by CMV drivers and training on appropriate... regulations with the FMCSRs and HMRs. (m) A copy of any new law or regulation affecting CMV safety enforcement...

  14. Power Technologies Data Book 2003 Edition

    Energy Technology Data Exchange (ETDEWEB)

    Aabakken, J.

    2004-06-01

    The 2003 edition of this report, prepared by NREL's Energy Analysis Office, includes up-to-date information on power technologies, including complete technology profiles. The data book also contains charts on electricity restructuring, power technology forecasts and comparisons, electricity supply, electricity capability, electricity generation, electricity demand, prices, economic indicators, environmental indicators, conversion factors, and selected congressional questions and answers.

  15. Developments in lubricant technology

    CERN Document Server

    Srivastava, S P

    2014-01-01

    Provides a fundamental understanding of lubricants and lubricant technology including emerging lubricants such as synthetic and environmentally friendly lubricants Teaches the reader to understand the role of technology involved in the manufacture of lubricants Details both major industrial oils and automotive oils for various engines Covers emerging lubricant technology such as synthetic and environmentally friendly lubricants Discusses lubricant blending technology, storage, re-refining and condition monitoring of lubricant in equipment

  16. Emerging and Disruptive Technologies

    OpenAIRE

    Kricka, Larry J.

    2016-01-01

    Several emerging or disruptive technologies can be identified that might, at some point in the future, displace established laboratory medicine technologies and practices. These include increased automation in the form of robots, 3-D printing, technology convergence (e.g., plug-in glucose meters for smart phones), new point-of-care technologies (e.g., contact lenses with sensors, digital and wireless enabled pregnancy tests) and testing locations (e.g., Retail Health Clinics, new at-home test...

  17. Plans & Policies for Technology in Education: A Compendium. A Technology Leadership Network Special Report.

    Science.gov (United States)

    National School Boards Association, Alexandria, VA. Inst. for the Transfer of Technology to Education.

    This document shows how education leaders nationwide--many of them part of the National School Boards Association's 345-district Technology Leadership Network--have addressed technology-related policy issues such as copyright, purchasing, network/Internet use, and ethics as well as technology planning topics including staff development, classroom…

  18. Modeling technological learning and its application for clean coal technologies in Japan

    International Nuclear Information System (INIS)

    Nakata, Toshihiko; Sato, Takemi; Wang, Hao; Kusunoki, Tomoya; Furubayashi, Takaaki

    2011-01-01

    Estimating technological progress of emerging technologies such as renewables and clean coal technologies becomes important for designing low carbon energy systems in future and drawing effective energy policies. Learning curve is an analytical approach for describing the decline rate of cost and production caused by technological progress as well as learning. In the study, a bottom-up energy-economic model including an endogenous technological learning function has been designed. The model deals with technological learning in energy conversion technologies and its spillover effect. It is applied as a feasibility study of clean coal technologies such as IGCC (Integrated Coal Gasification Combined Cycle) and IGFC (Integrated Coal Gasification Fuel Cell System) in Japan. As the results of analysis, it is found that technological progress by learning has a positive impact on the penetration of clean coal technologies in the electricity market, and the learning model has a potential for assessing upcoming technologies in future.

  19. Sensor Technologies on Flexible Substrates

    Science.gov (United States)

    Koehne, Jessica

    2016-01-01

    NASA Ames has developed sensor technologies on flexible substrates integrated into textiles for personalized environment monitoring and human performance evaluation. Current technologies include chemical sensing for gas leak and event monitoring and biological sensors for human health and performance monitoring. Targeted integration include next generation EVA suits and flexible habitats.

  20. Predicting nurses' use of healthcare technology using the technology acceptance model: an integrative review.

    Science.gov (United States)

    Strudwick, Gillian

    2015-05-01

    The benefits of healthcare technologies can only be attained if nurses accept and intend to fully use them. One of the most common models utilized to understand user acceptance of technology is the Technology Acceptance Model. This model and modified versions of it have only recently been applied in the healthcare literature among nurse participants. An integrative literature review was conducted on this topic. Ovid/MEDLINE, PubMed, Google Scholar, and CINAHL were searched yielding a total of 982 references. Upon eliminating duplicates and applying the inclusion and exclusion criteria, the review included a total of four dissertations, three symposium proceedings, and 13 peer-reviewed journal articles. These documents were appraised and reviewed. The results show that a modified Technology Acceptance Model with added variables could provide a better explanation of nurses' acceptance of healthcare technology. These added variables to modified versions of the Technology Acceptance Model are discussed, and the studies' methodologies are critiqued. Limitations of the studies included in the integrative review are also examined.

  1. Eco-Friendly Alternative Refrigeration Systems -R-ES-O-N-A-N--CE ...

    Indian Academy of Sciences (India)

    An electrical signal may be converted to acoustical (i.e. ... Thermoacoustic Refrigeration System. In a simple ... Tc and rejecting Wclste heat power Qh to a heat sink at T h. •. In .... use where eco-friendliness, simplicity, reliability or low cost is.

  2. Saturation mechanism of the heat release response of a premixed swirl flame using LES

    NARCIS (Netherlands)

    Krediet, H.J.; Beck, C. H.; Krebs, W.; Kok, J. B.W.

    2013-01-01

    The nonlinear heat release response of a premixed swirl flame to velocity perturbations is investigated using Large Eddy Simulation. The nonlinear heat release response is required for the prediction of thermoacoustic limit cycle pressure amplitudes and is represented here by the Flame Describing

  3. Teaching Machines, Programming, Computers, and Instructional Technology: The Roots of Performance Technology.

    Science.gov (United States)

    Deutsch, William

    1992-01-01

    Reviews the history of the development of the field of performance technology. Highlights include early teaching machines, instructional technology, learning theory, programed instruction, the systems approach, needs assessment, branching versus linear program formats, programing languages, and computer-assisted instruction. (LRW)

  4. Production, control and utilization of radioisotopes including radiopharmaceuticals

    International Nuclear Information System (INIS)

    Muenze, R.

    1985-05-01

    From April 29th to May 5th, 1984 27 participants from 21 developing countries stayed within an IAEA Study Tour ('Production, Control and Utilization of Radioisotopes including Radiopharmaceuticals') in the GDR. In the CINR, Rossendorf the reactor, the cyclotron, the technological centre as well as the animal test laboratory were visited. The participants were made familiar by 10 papers with the development, production and control of radiopharmaceuticals in the CINR, Rossendorf. (author)

  5. Conventional Oil and Gas Technologies. IEA ETSAP technology brief P01

    Energy Technology Data Exchange (ETDEWEB)

    Seljom, Pernille [IFE (Norway)], E-mail: pernille.seljom@ife.no

    2010-05-15

    This technology brief on conventional oil and gas technologies is part of a series produced by the IEA ETSAP agreement called the energy technology data source (E-Tech-DS). The E-Tech-DS series consists of a number of 5-10 page technology briefs similar to the IEA Energy Technology Essentials. Based on the data collected for the models that the Energy Technology Systems Analysis Programme (ETSAP) is known for, ETSAP also prepares technology briefs, called E-TechDS. The E-TechDS briefs are standardized presentations of basic information (process, status, performance, costs, potential, and barriers) for key energy technology clusters. Each brief includes an overview of the technology, charts and graphs, and a summary data table, and usually ending with some key references and further information. The E TechDS briefs are intended to offer essential, reliable and quantitative information to energy analysts, experts, policymakers, investors and media from both developed and developing countries. This specific brief focuses on the state of oil and gas exploration, development, and production/recovery technologies.

  6. 75 FR 49526 - Halliburton Company, Duncan Mfg., Including On-Site Leased Workers from Express Personnel...

    Science.gov (United States)

    2010-08-13

    ... Company, Duncan Mfg., Including On-Site Leased Workers from Express Personnel, Clayton Personnel Service, and Manpower Planning, Duncan, OK; Halliburton Company, Technology and Engineering Division, Finance... Halliburton Company, Technology and Engineering Division, and Finance and Administration Division, Duncan...

  7. Chemistry Technology

    Data.gov (United States)

    Federal Laboratory Consortium — Chemistry technology experts at NCATS engage in a variety of innovative translational research activities, including:Design of bioactive small molecules.Development...

  8. New technologies and electricity production

    International Nuclear Information System (INIS)

    Pantoja Lopez, A.

    1993-01-01

    This paper presents a general overview about the new electrical energy generation technologies, under development, in some cases with the spanish electrical utilities cooperation. The content has a brief introductory description about the highly changing scenario for the utilities, the most promising generation technologies from the point of view of efficiency, cost investment, and minimum environmental impact, and the main actions included in the Spanish Energetic Research Plan (PEN-91-2000). After a short presentation for the advanced clean coal technologies, as PFC,IGCC, fuel cells and MHD, as well as some ongoing research projects, it has been included a group of nuclear and renewable energy generation technologies and the main environmental control technologies, all of them with great interest for the near term electric utilities power generation. (Author)

  9. Y-12 Plant Remedial Action technology logic diagram. Volume I: Technology evaluation

    International Nuclear Information System (INIS)

    1994-09-01

    The Y-12 Plant Remedial Action Program addresses remediation of the contaminated groundwater, surface water and soil in the following areas located on the Oak Ridge Reservation: Chestnut Ridge, Bear Creek Valley, the Upper and Lower East Fork Popular Creek Watersheds, CAPCA 1, which includes several areas in which remediation has been completed, and CAPCA 2, which includes dense nonaqueous phase liquid wells and a storage facility. There are many facilities within these areas that are contaminated by uranium, mercury, organics, and other materials. This Technology Logic Diagram identifies possible remediation technologies that can be applied to the soil, water, and contaminants for characterization, treatment, and waste management technology options are supplemented by identification of possible robotics or automation technologies. These would facilitate the cleanup effort by improving safety, of remediation, improving the final remediation product, or decreasing the remediation cost. The Technology Logic Diagram was prepared by a diverse group of more than 35 scientists and engineers from across the Oak Ridge Reservation. Most are specialists in the areas of their contributions. 22 refs., 25 tabs

  10. Technology Transfer and Technology Transfer Intermediaries

    Science.gov (United States)

    Bauer, Stephen M.; Flagg, Jennifer L.

    2010-01-01

    A standard and comprehensive model is needed to evaluate and compare technology transfer systems and the stakeholders within these systems. The principle systems considered include federal laboratories, U.S. universities, the rehabilitation engineering research centers (RERCs), and large small business innovation research programs. An earlier…

  11. Power Technologies Energy Data Book - Fourth Edition

    Energy Technology Data Exchange (ETDEWEB)

    Aabakken, J.

    2006-08-01

    This report, prepared by NREL's Strategic Energy Analysis Center, includes up-to-date information on power technologies, including complete technology profiles. The data book also contains charts on electricity restructuring, power technology forecasts, electricity supply, electricity capability, electricity generation, electricity demand, prices, economic indicators, environmental indicators, and conversion factors.

  12. Power Technologies Energy Data Book - Third Edition

    Energy Technology Data Exchange (ETDEWEB)

    Aabakken, J.

    2005-04-01

    This report, prepared by NREL's Energy Analysis Office, includes up-to-date information on power technologies, including complete technology profiles. The data book also contains charts on electricity restructuring, power technology forecasts, electricity supply, electricity capability, electricity generation, electricity demand, prices, economic indicators, environmental indicators, and conversion factors.

  13. Global Collaboration Enhances Technology Literacy

    Science.gov (United States)

    Cook, Linda A.; Bell, Meredith L.; Nugent, Jill; Smith, Walter S.

    2016-01-01

    Today's learners routinely use technology outside of school to communicate, collaborate, and gather information about the world around them. Classroom learning experiences are relevant when they include communication technologies such as social networking, blogging, and video conferencing, and information technologies such as databases, browsers,…

  14. Teacher Models of Technology Integration.

    Science.gov (United States)

    Peterman, Leinda

    2003-01-01

    Provides examples of best practices in technology integration from five Technology Innovation Challenge Grant (TICG) programs, funded through the Department of Education to meet the No Child Left Behind technology goals. Highlights include professional development activities in Louisiana and New Mexico; collaborative learning applications; and…

  15. Designing Human Technologies

    DEFF Research Database (Denmark)

    Simonsen, Jesper

    and the design process, in ethical and society-related concerns, and in evaluating how designs fulfill needs and solve problems. Designing Human Technologies subscribes to a broad technology concept including information and communication, mobile, environmental/sustainable and energy technologies......Design is increasingly becoming a part of the university curriculum and research agenda. The keynote present and discuss Designing Human Technologies – an initiative aiming at establishing a design oriented main subject area alongside traditional main subject areas such as Natural Science......, the Humanities, and Social Science. The initiative broadens the perspective of IS and recognize reflections on aesthetics, ethics, values, connections to politics, and strategies for enabling a better future as legitimate parts of the research agenda. Designing Human Technologies is a design-oriented Strategic...

  16. SHARED TECHNOLOGY TRANSFER PROGRAM

    Energy Technology Data Exchange (ETDEWEB)

    GRIFFIN, JOHN M. HAUT, RICHARD C.

    2008-03-07

    The program established a collaborative process with domestic industries for the purpose of sharing Navy-developed technology. Private sector businesses were educated so as to increase their awareness of the vast amount of technologies that are available, with an initial focus on technology applications that are related to the Hydrogen, Fuel Cells and Infrastructure Technologies (Hydrogen) Program of the U.S. Department of Energy. Specifically, the project worked to increase industry awareness of the vast technology resources available to them that have been developed with taxpayer funding. NAVSEA-Carderock and the Houston Advanced Research Center teamed with Nicholls State University to catalog NAVSEA-Carderock unclassified technologies, rated the level of readiness of the technologies and established a web based catalog of the technologies. In particular, the catalog contains technology descriptions, including testing summaries and overviews of related presentations.

  17. Information technology made simple

    CERN Document Server

    Carter, Roger

    1991-01-01

    Information Technology: Made Simple covers the full range of information technology topics, including more traditional subjects such as programming languages, data processing, and systems analysis. The book discusses information revolution, including topics about microchips, information processing operations, analog and digital systems, information processing system, and systems analysis. The text also describes computers, computer hardware, microprocessors, and microcomputers. The peripheral devices connected to the central processing unit; the main types of system software; application soft

  18. Responsible technology acceptance

    DEFF Research Database (Denmark)

    Toft, Madeleine Broman; Schuitema, Geertje; Thøgersen, John

    2014-01-01

    As a response to climate change and the desire to gain independence from imported fossil fuels, there is a pressure to increase the proportion of electricity from renewable sources which is one of the reasons why electricity grids are currently being turned into Smart Grids. In this paper, we focus...... on private consumers’ acceptance of having Smart Grid technology installed in their home. We analyse acceptance in a combined framework of the Technology Acceptance Model and the Norm Activation Model. We propose that individuals are only likely to accept Smart Grid technology if they assess usefulness...... in terms of a positive impact for society and the environment. Therefore, we expect that Smart Grid technology acceptance can be better explained when the well-known technology acceptance parameters included in the Technology Acceptance Model are supplemented by moral norms as suggested by the Norm...

  19. Fiber based hydrophones for ultra-high energy neutrino detection

    NARCIS (Netherlands)

    Buis, E.J.; Doppenberg, E.J.J.; Eijk, D. van; Lahmann, R.; Nieuwland, R.A.; Toet, P.M.

    2014-01-01

    It is a well studied process [1, 2] that energy deposition of cosmic ray particles in water that generate thermo-acoustic signals. Hydrophones of sufficient sensitivity could measure this signal and provide a means of detecting ultra-high energetic cosmic neutrinos. We investigate optical

  20. Acoustic scattering behavior of a 2D flame with heat exchanger in cross-flow

    NARCIS (Netherlands)

    Chen, L.S.; Polifke, W.; Hosseini, N.; Teerling, O. J.; Arteaga, I.L.; Kornilov, V.; De Goey, P.

    2016-01-01

    In practical heat production systems, premixed flames with cold heat exchanger in cross-flow is a widely used configuration. Self-excited thermoacoustic instabilities often occur in such systems. A practical way to predict the presence of the instabilities is the network model approach. In the

  1. Promoting renewable energy technologies

    International Nuclear Information System (INIS)

    Grenaa Jensen, S.

    2004-06-01

    Technologies using renewable energy sources are receiving increasing interest from both public authorities and power producing companies, mainly because of the environmental advantages they procure in comparison with conventional energy sources. These technologies can be substitution for conventional energy sources and limit damage to the environment. Furthermore, several of the renewable energy technologies satisfy an increasing political goal of self-sufficiency within energy production. The subject of this thesis is promotion of renewable technologies. The primary goal is to increase understanding on how technological development takes place, and establish a theoretical framework that can assist in the construction of policy strategies including instruments for promotion of renewable energy technologies. Technological development is analysed by through quantitative and qualitative methods. (BA)

  2. Gas-fired electric power generating technologies

    International Nuclear Information System (INIS)

    1994-09-01

    The workshop that was held in Madrid 25-27 May 1994 included participation by experts from 16 countries. They represented such diverse fields and disciplines as technology, governmental regulation, economics, and environment. Thus, the participants provided an excellent cross section of key areas and a diversity of viewpoints. At the workshop, a broad range of topics regarding gas-fired electric power generation was discussed. These included political, regulatory and financial issues as well as more specific technical questions regarding the environment, energy efficiency, advanced generation technologies and the status of competitive developments. Important technological advances in gas-based power and CHP technologies have already been achieved including higher energy efficiency and lower emissions, with further improvements expected in the near future. Advanced technology trends include: (a) The use of gas technology to reduce emissions from existing coal-fired power plants. (b) The wide-spread application of combined-cycle gas turbines in new power plants and the growing use of aero-derivative gas turbines in CHP applications. (c) Phosphoric acid fuel cells that are being introduced commercially. Their market penetration will grow over the next 10 years. The next generation of fuel cells (solid oxide and molten carbonate) is expected to enter the market around the year 2000. (EG)

  3. Bioprinting technology and its applications.

    Science.gov (United States)

    Seol, Young-Joon; Kang, Hyun-Wook; Lee, Sang Jin; Atala, Anthony; Yoo, James J

    2014-09-01

    Bioprinting technology has emerged as a powerful tool for building tissue and organ structures in the field of tissue engineering. This technology allows precise placement of cells, biomaterials and biomolecules in spatially predefined locations within confined three-dimensional (3D) structures. Various bioprinting technologies have been developed and utilized for applications in life sciences, ranging from studying cellular mechanisms to constructing tissues and organs for implantation, including heart valve, myocardial tissue, trachea and blood vessels. In this article, we introduce the general principles and limitations of the most widely used bioprinting technologies, including jetting- and extrusion-based systems. Application-based research focused on tissue regeneration is presented, as well as the current challenges that hamper clinical utility of bioprinting technology. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  4. Fusion technology 1992

    International Nuclear Information System (INIS)

    Ferro, C.; Gasparatto, M.; Knoepfel, H.

    1993-01-01

    The aim of the biennial series of symposia on the title subject, organized by the European Fusion Laboratories, is the exchange of information on the design, construction and operation of fusion experiments and on the technology being developed for the next step devices and fusion reactors. The coverage of the volume includes the technological aspects of fusion reactors in relation to new developments, this forming a guideline for the definition of future work. These proceedings comprise three volumes and contain both the invited lectures and contributed papers presented at the symposium which was attended by 569 participants from around the globe. The 343 papers, including 12 invited papers, characterize the increasing interest of industry in the fusion programme, giving a broad and current overview on the progress and trends fusion technology is experiencing now, as well as indicating the future for fusion devices

  5. Evaluating New Technology.

    Science.gov (United States)

    Carniol, Paul J; Heffelfinger, Ryan N; Grunebaum, Lisa D

    2018-05-01

    There are multiple complex issues to consider when evaluating any new technology. First evaluate the efficacy of the device. Then considering your patient population decide whether this technology brings an added benefit to your patients. If it meets these 2 criteria, then proceed to the financial analysis of acquiring this technology. The complete financial analysis has several important components that include but are not limited to cost, value, alternatives, return on investment, and associated marketing expense. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Technology Transfer: A Third World Perspective.

    Science.gov (United States)

    Akubue, Anthony I.

    2002-01-01

    Technology transfer models are based on assumptions that do not reflect Third-World realities. Obstacles to building indigenous technology capacity include multinational corporations' control of innovations, strings attached to foreign aid, and indigenous reluctance to undertake research. Four areas of development include foreign direct…

  7. Cancer Technology - Cancer Currents Blog

    Science.gov (United States)

    Blog posts on technologies that affect cancer research and care—including new technologies for detecting cancer, testing treatments, storing/analyzing data, and improving patient care—from NCI Cancer Currents.

  8. Forecasting and management of technology

    National Research Council Canada - National Science Library

    Roper, A. T

    2011-01-01

    .... The scope of this edition has broadened to include management of technology content that is relevant to now to executives in organizations while updating and strengthening the technology forecasting...

  9. Department of Reactor Technology

    DEFF Research Database (Denmark)

    Risø National Laboratory, Roskilde

    The general development of the Department of Reactor Technology at Risø during 1981 is presented, and the activities within the major subject fields are described in some detail. Lists of staff, publications, and computer programs are included.......The general development of the Department of Reactor Technology at Risø during 1981 is presented, and the activities within the major subject fields are described in some detail. Lists of staff, publications, and computer programs are included....

  10. Overview of existing cartilage repair technology.

    Science.gov (United States)

    McNickle, Allison G; Provencher, Matthew T; Cole, Brian J

    2008-12-01

    Currently, autologous chondrocyte implantation and osteochondral grafting bridge the gap between palliation of cartilage injury and resurfacing via arthroplasty. Emerging technologies seek to advance first generation techniques and accomplish several goals including predictable outcomes, cost-effective technology, single-stage procedures, and creation of durable repair tissue. The biologic pipeline represents a variety of technologies including synthetics, scaffolds, cell therapy, and cell-infused matrices. Synthetic constructs, an alternative to biologic repair, resurface a focal chondral defect rather than the entire joint surface. Scaffolds are cell-free constructs designed as a biologic "net" to augment marrow stimulation techniques. Minced cartilage technology uses stabilized autologous or allogeneic fragments in 1-stage transplantation. Second and third generation cell-based methods include alternative membranes, chondrocyte seeding, and culturing onto scaffolds. Despite the promising early results of these products, significant technical obstacles remain along with unknown long-term durability. The vast array of developing technologies has exceptional promise and the potential to revolutionize the cartilage treatment algorithm within the next decade.

  11. Technology transfer for adaptation

    Science.gov (United States)

    Biagini, Bonizella; Kuhl, Laura; Gallagher, Kelly Sims; Ortiz, Claudia

    2014-09-01

    Technology alone will not be able to solve adaptation challenges, but it is likely to play an important role. As a result of the role of technology in adaptation and the importance of international collaboration for climate change, technology transfer for adaptation is a critical but understudied issue. Through an analysis of Global Environment Facility-managed adaptation projects, we find there is significantly more technology transfer occurring in adaptation projects than might be expected given the pessimistic rhetoric surrounding technology transfer for adaptation. Most projects focused on demonstration and early deployment/niche formation for existing technologies rather than earlier stages of innovation, which is understandable considering the pilot nature of the projects. Key challenges for the transfer process, including technology selection and appropriateness under climate change, markets and access to technology, and diffusion strategies are discussed in more detail.

  12. Communication and collaboration technologies.

    Science.gov (United States)

    Cheeseman, Susan E

    2012-01-01

    This is the third in a series of columns exploring health information technology (HIT) in the neonatal intensive care unit (NICU). The first column provided background information on the implementation of information technology throughout the health care delivery system, as well as the requisite informatics competencies needed for nurses to fully engage in the digital era of health care. The second column focused on information and resources to master basic computer competencies described by the TIGER initiative (Technology Informatics Guiding Education Reform) as learning about computers, computer networks, and the transfer of data.1 This column will provide additional information related to basic computer competencies, focusing on communication and collaboration technologies. Computers and the Internet have transformed the way we communicate and collaborate. Electronic communication is the ability to exchange information through the use of computer equipment and software.2 Broadly defined, any technology that facilitates linking one or more individuals together is a collaborative tool. Collaboration using technology encompasses an extensive range of applications that enable groups of individuals to work together including e-mail, instant messaging (IM ), and several web applications collectively referred to as Web 2.0 technologies. The term Web 2.0 refers to web applications where users interact and collaborate with each other in a collective exchange of ideas generating content in a virtual community. Examples of Web 2.0 technologies include social networking sites, blogs, wikis, video sharing sites, and mashups. Many organizations are developing collaborative strategies and tools for employees to connect and interact using web-based social media technologies.3.

  13. Contemporary design and manufacturing technology

    CERN Document Server

    Wang, Taiyong; Zuo, Dunwen

    2013-01-01

    The special topic volume communicates the latest progress and research results of new theory, new technology, method, equipment and so on in Engineering Technology, and to grasp the updated technological and research trends in internationally. The major topics covered by the special volumes include Advanced Materials and Manufacturing Technologies, Control, Automation and Detection Systems, Advanced Design Technology, Optimization and Modeling. In 80 invited and peer-reviewed papers, mechanical and other engineers describe their recent and current research and results in advanced materials and

  14. Technology to optimize pediatric diabetes management and outcomes.

    Science.gov (United States)

    Markowitz, Jessica T; Harrington, Kara R; Laffel, Lori M B

    2013-12-01

    Technology for diabetes management is rapidly developing and changing. With each new development, there are numerous factors to consider, including medical benefits, impact on quality of life, ease of use, and barriers to use. It is also important to consider the interaction between developmental stage and technology. This review considers a number of newer diabetes-related technologies and explores issues related to their use in the pediatric diabetes population (including young adults), with a focus on psychosocial factors. Areas include trend technology in blood glucose monitoring, continuous glucose monitoring, sensor-augmented insulin pumps and low glucose suspend functions, internet applications including videoconferencing, mobile applications (apps), text messaging, and online gaming.

  15. 75 FR 76487 - Haldex Brake Corporation, Commercial Vehicle Systems, Including On-Site Leased Workers of...

    Science.gov (United States)

    2010-12-08

    ..., Commercial Vehicle Systems, Including On-Site Leased Workers of Johnston Integration Technologies, a... Adjustment Assistance In accordance with Section 223 of the Trade Act of 1974, as amended (``Act''), 19 U.S.C... system components. The company reports that workers leased from Johnston Integration Technologies, a...

  16. Advanced Radioisotope Power Conversion Technology Research and Development

    Science.gov (United States)

    Wong, Wayne A.

    2004-01-01

    NASA's Radioisotope Power Conversion Technology program is developing next generation power conversion technologies that will enable future missions that have requirements that cannot be met by either the ubiquitous photovoltaic systems or by current Radioisotope Power System (RPS) technology. Performance goals of advanced radioisotope power systems include improvement over the state-of-practice General Purpose Heat Source/Radioisotope Thermoelectric Generator by providing significantly higher efficiency to reduce the number of radioisotope fuel modules, and increase specific power (watts/kilogram). Other Advanced RPS goals include safety, long-life, reliability, scalability, multi-mission capability, resistance to radiation, and minimal interference with the scientific payload. NASA has awarded ten contracts in the technology areas of Brayton, Stirling, Thermoelectric, and Thermophotovoltaic power conversion including five development contracts that deal with more mature technologies and five research contracts. The Advanced RPS Systems Assessment Team includes members from NASA GRC, JPL, DOE and Orbital Sciences whose function is to review the technologies being developed under the ten Radioisotope Power Conversion Technology contracts and assess their relevance to NASA's future missions. Presented is an overview of the ten radioisotope power conversion technology contracts and NASA's Advanced RPS Systems Assessment Team.

  17. Energy storage technology for electric and hybrid vehicles. Matching technology to design requirements

    Energy Technology Data Exchange (ETDEWEB)

    Wahlstroem, J. [Sycon Energikonsult AB, Malmoe (Sweden)

    1999-12-01

    A central issue when dealing with electrical vehicles has always been how to store energy in sufficient quantities. On April 27 through 28 1999 a workshop was held on this matter at University of California Davis (UC Davis). Organizer and host was Dr. Andrew Burke and the Institute of Transportation Studies (ITS) at UC Davis. The workshop included battery technology, ultra capacitors and fly wheels, but did not include fuel cell technology. In this paper the conference is reviewed with the emphasis on battery development. A section on ultra capacitors and flywheels is also included. The overall observation made at the conference is that most of the effort on energy storage in electric and hybrid vehicles are put into batteries. There is some development on ultra capacitors but almost none on flywheels. The battery also seems to be the choice of the car industry at this point, especially the pulse battery for engine dominant hybrid vehicles, like the Toyota Prius. The battery manufacturers seem to focus more on technology development than cost reduction at this point. An important technological issue as of now is to improve thermal management in order to increase life of the batteries. But when the technological goals are met focus must shift to cost minimization and marketing if the battery electric vehicle shall make a market break through.

  18. A Unifying Account of Technological Knowledge: Animal Construction, Tool Use, and Technology

    OpenAIRE

    Heflin, Ashley Shew

    2011-01-01

    Philosophers, historians of technology, and anthropologists often offer accounts of technology that include a â human clause,â some phrase to the effect that only humans use or make technologies. When these academics do consider tool use, they refer to a few cases, usually from chimpanzee studies, as special and unusual in the animal kingdom and whose similarities to human tool use can be explained through some shared evolutionary heritage. However, new observational and laboratory animal ...

  19. Integrating medical, assistive, and universal design products and technologies: Assistive Technology Service Method (ATSM).

    Science.gov (United States)

    Elsaesser, Linda-Jeanne; Bauer, Stephen

    2012-07-01

    ISO26000 provides guidance on effective organizational performance that recognizes social responsibility (including rights of persons with disabilities (PWD)), engages stakeholders, and contributes to sustainable development [1]. Millennium Development Goals 2010 state: while progress has been made, insufficient dedication to sustainable development, and inequalities to the most vulnerable people require attention [2]. World Report on Disability 2011 recommendations includes improved data collection and removal of barriers to rehabilitation that empower PWD [3]. The Assistive Technology Service Method (ATSM), Assistive Technology Device Classification (ATDC) and Matching Person and Technology (MPT) provide an evidence-based, standardized, internationally comparable framework to improve rehabilitation interventions [4-6]. The ATSM and ATDC support universal design (UD) principles and provision of universal technology. The MPT assures interventions are effective and satisfactory to end-users [7]. The ICF conceptual framework and common language are used throughout [8]. Research findings on healthcare needs are translated. ATSM applications in support of these findings are presented. National initiatives demonstrate the need and value of the ATSM as an evidence-based, user-centric, interdisciplinary method to improve individual and organizational performance for rehabilitation [including AT] services. Two Disability & Rehabilitation: Assistive Technology articles demonstrate ATSM and ATDC use to strengthen rehabilitation services and integrate Universal Design principles for socially responsible behavior.

  20. Low-rank coal research annual report, July 1, 1989--June 30, 1990 including quarterly report, April--June 1990

    Energy Technology Data Exchange (ETDEWEB)

    1990-11-01

    Research programs in the following areas are presented: control technology and coal preparation; advance research and technology development; combustion; liquefaction; and gasification. Sixteen projects are included. Selected items have been processed separately for inclusion in the Energy Science and Technology Database.

  1. Libraries, Self-Censorship, and Information Technologies.

    Science.gov (United States)

    Buschman, John

    1994-01-01

    Explores the theme of self-censorship in libraries in relation to new technologies. Highlights include the results of investing in high-cost electronic resources at the expense of traditional, lower-status formats; the effect of information technologies on literacy and historical records; and market censorship, including centralization and…

  2. Technology '90

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    The US Department of Energy (DOE) laboratories have a long history of excellence in performing research and development in a number of areas, including the basic sciences, applied-energy technology, and weapons-related technology. Although technology transfer has always been an element of DOE and laboratory activities, it has received increasing emphasis in recent years as US industrial competitiveness has eroded and efforts have increased to better utilize the research and development resources the laboratories provide. This document, Technology '90, is the latest in a series that is intended to communicate some of the many opportunities available for US industry and universities to work with the DOE and its laboratories in the vital activity of improving technology transfer to meet national needs. Technology '90 is divided into three sections: Overview, Technologies, and Laboratories. The Overview section describes the activities and accomplishments of the DOE research and development program offices. The Technologies section provides descriptions of new technologies developed at the DOE laboratories. The Laboratories section presents information on the missions, programs, and facilities of each laboratory, along with a name and telephone number of a technology transfer contact for additional information. Separate papers were prepared for appropriate sections of this report.

  3. TECHNOLOGY ROADMAPPING FOR IAEA SEALS.

    Energy Technology Data Exchange (ETDEWEB)

    HOFFHEINS,B.; ANNESE,C.; GOODMAN,M.; OCONNOR,W.; GUSHUE,S.; PEPPER,S.

    2003-07-13

    In the fall of 2002, the U.S. Support Program (USSP) initiated an effort to define a strategy or ''roadmap'' for future seals technologies and to develop a generalized process for planning safeguards equipment development, which includes seals and other safeguards equipment. The underlying objectives of the USSP include becoming more proactive than reactive in addressing safeguards equipment needs, helping the IAEA to maintain an inventory of cost-effective, reliable, and effective safeguards equipment, establishing a long-term planning horizon, and securing IAEA ownership in the process of effective requirements definition and timely transitioning of new or improved systems for IAEA use. At an initial workshop, seals, their functions, performance issues, and future embodiments were discussed in the following order: adhesive seals, metal seals, passive and active loop seals, ultrasonic seals, tamper indicating enclosures (including sample containers, equipment enclosures, and conduits). Suggested improvements to these technologies focused largely on a few themes: (1) The seals must be applied quickly, easily, and correctly; (2) Seals and their associated equipment should not unduly add bulk or weight to the inspectors load; (3) Rapid, in-situ verifiability of seals is desirable; and (4) Seal systems for high risk or high value applications should have two-way, remote communications. Based upon these observations and other insights, the participants constructed a skeletal approach for seals technology planning. The process begins with a top-level review of the fundamental safeguards requirements and extraction of required system features, which is followed by analysis of suitable technologies and identification of technology gaps, and finally by development of a planning schedule for system improvements and new technology integration. Development of a comprehensive procedure will require the partnership and participation of the IAEA. The

  4. Uranium extraction technology

    International Nuclear Information System (INIS)

    1993-01-01

    In 1983 the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development (OECD/NEA) and the IAEA jointly published a book on Uranium Extraction Technology. A primary objective of this report was to document the significant technological developments that took place during the 1970s. The purpose of this present publication is to update and expand the original book. It includes background information about the principle of the unit operations used in uranium ore processing and summarizes the current state of the art. The publication also seeks to preserve the technology and the operating 'know-how' developed over the past ten years. This publication is one of a series of Technical Reports on uranium ore processing that have been prepared by the Division of Nuclear Fuel Cycle and Waste Management at the IAEA. A complete list of these reports is included as an addendum. Refs, figs and tabs

  5. Technology Roadmap: Hydropower

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Hydropower could double its contribution by 2050, reaching 2,000 GW of global capacity and over 7,000 TWh. This achievement, driven primarily by the quest of clean electricity, could prevent annual emissions of up to 3 billion tonnes of CO2 from fossil-fuel plants. The bulk of this growth would come from large plants in emerging economies and developing countries. Hydroelectricity’s many advantages include reliability, proven technology, large storage capacity, and very low operating and maintenance costs. Hydropower is highly flexible, a precious asset for electricity network operators, especially given rapid expansion of variable generation from other renewable energy technologies such as wind power and photovoltaics. Many hydropower plants also provide flood control, irrigation, navigation and freshwater supply. The technology roadmap for Hydropower details action needed from policy makers to allow hydroelectric production to double, and addresses necessary conditions, including resolving environmental issues and gaining public acceptance.

  6. New technology for food systems and security.

    Science.gov (United States)

    Yau, N J Newton

    2009-01-01

    In addition to product trade, technology trade has become one of the alternatives for globalization action around the world. Although not all technologies employed on the technology trade platform are innovative technologies, the data base of international technology trade still is a good indicator for observing innovative technologies around world. The technology trade data base from Sinew Consulting Group (SCG) Ltd. was employed as an example to lead the discussion on security or safety issues that may be caused by these innovative technologies. More technologies related to processing, functional ingredients and quality control technology of food were found in the data base of international technology trade platform. The review was conducted by categorizing technologies into the following subcategories in terms of safety and security issues: (1) agricultural materials/ingredients, (2) processing/engineering, (3) additives, (4) packaging/logistics, (5) functional ingredients, (6) miscellaneous (include detection technology). The author discusses examples listed for each subcategory, including GMO technology, nanotechnology, Chinese medicine based functional ingredients, as well as several innovative technologies. Currently, generation of innovative technology advance at a greater pace due to cross-area research and development activities. At the same time, more attention needs to be placed on the employment of these innovative technologies.

  7. Synergistic smart fuel for in-pile nuclear reactor measurements

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.A.; Kotter, D.K. [Idaho National Laboratories, Idaho Falls (United States); Ali, R.A.; Garrett, S.L. [Penn State University, University Park, State College, PA 16801 (United States)

    2013-07-01

    The thermo-acoustic fuel rod sensor developed in this research has demonstrated a novel technique for monitoring the temperature within the core of a nuclear reactor or the temperature of the surrounding heat-transfer fluid. It uses the heat from the nuclear fuel to generate sustained acoustic oscillations whose frequency will be indicative of the temperature. Converting a nuclear fuel rod into this type of thermo-acoustic sensor simply requires the insertion of a porous material (stack). This sensor has demonstrated a synergy with the elevated temperatures that exist within the nuclear reactor using materials that have only minimal susceptibility to high-energy particle fluxes. When the sensor is in operation, the sound waves radiated from the fuel rod resonator will propagate through the surrounding cooling fluid. The frequency of these oscillations is directly correlated with an effective temperature within the fuel rod resonator. This device is self-powered and is operational even in case of total loss of power of the reactor.

  8. High Temperature Dynamic Pressure Measurements Using Silicon Carbide Pressure Sensors

    Science.gov (United States)

    Okojie, Robert S.; Meredith, Roger D.; Chang, Clarence T.; Savrun, Ender

    2014-01-01

    Un-cooled, MEMS-based silicon carbide (SiC) static pressure sensors were used for the first time to measure pressure perturbations at temperatures as high as 600 C during laboratory characterization, and subsequently evaluated in a combustor rig operated under various engine conditions to extract the frequencies that are associated with thermoacoustic instabilities. One SiC sensor was placed directly in the flow stream of the combustor rig while a benchmark commercial water-cooled piezoceramic dynamic pressure transducer was co-located axially but kept some distance away from the hot flow stream. In the combustor rig test, the SiC sensor detected thermoacoustic instabilities across a range of engine operating conditions, amplitude magnitude as low as 0.5 psi at 585 C, in good agreement with the benchmark piezoceramic sensor. The SiC sensor experienced low signal to noise ratio at higher temperature, primarily due to the fact that it was a static sensor with low sensitivity.

  9. Designing a TAC thermometer from a VHTR graphite structure

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James A., E-mail: James.Smith@INL.gov; Kotter, Dale, E-mail: James.Smith@INL.gov [Fuel Performance and Design, Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Garrett, Steven L.; Ali, Randall A. [Graduate Program in Acoustics, Penn State University, State College, PA (United States)

    2015-03-31

    The interior of a nuclear reactor presents a particularly harsh and challenging environment for both sensors and telemetry due to high temperatures and high fluxes of energetic and ionizing particles among the radioactive decay products. Very High Temperature Reactors are pushing the in core temperatures even higher. A unique sensing approach will be discussed to address the necessary high temperature measurements. Thermoacoustic thermometry exploits high temperatures and uses materials that are immune to the effects of ionizing radiation to create a temperature sensor that is self-powered and wireless. In addition, the form-factor for the Thermoacoustic Thermometer (TACT) can be designed to be integrated within common in-pile structures. There are no physical moving parts required for TACT and the sensor is self-powered, as it uses the nuclear fuel for its heat source. TACT data will be presented from a laboratory prototype mimicking the design necessary for a VHTR graphite structure.

  10. Modified computation of the nozzle damping coefficient in solid rocket motors

    Science.gov (United States)

    Liu, Peijin; Wang, Muxin; Yang, Wenjing; Gupta, Vikrant; Guan, Yu; Li, Larry K. B.

    2018-02-01

    In solid rocket motors, the bulk advection of acoustic energy out of the nozzle constitutes a significant source of damping and can thus influence the thermoacoustic stability of the system. In this paper, we propose and test a modified version of a historically accepted method of calculating the nozzle damping coefficient. Building on previous work, we separate the nozzle from the combustor, but compute the acoustic admittance at the nozzle entry using the linearized Euler equations (LEEs) rather than with short nozzle theory. We compute the combustor's acoustic modes also with the LEEs, taking the nozzle admittance as the boundary condition at the combustor exit while accounting for the mean flow field in the combustor using an analytical solution to Taylor-Culick flow. We then compute the nozzle damping coefficient via a balance of the unsteady energy flux through the nozzle. Compared with established methods, the proposed method offers competitive accuracy at reduced computational costs, helping to improve predictions of thermoacoustic instability in solid rocket motors.

  11. Thermal enhanced vapor extraction systems: Design, application and performance prediction including contaminant behavior

    International Nuclear Information System (INIS)

    Phelan, J.M.; Webb, S.W.

    1994-01-01

    Soil heating technologies have been proposed as a method to accelerate contaminant removal from subsurface soils. These methods include the use of hot air, steam, conductive heaters, in-situ resistive heating and in-situ radiofrequency heating (Buettner et.al., EPA, Dev et.al., Heath et.al.). Criteria for selection of a particular soil heating technology is a complex function of contaminant and soil properties, and efficiency in energy delivery and contaminant removal technologies. The work presented here seeks to expand the understanding of the interactions of subsurface water, contaminant, heat and vacuum extraction through model predictions and field data collection. Field demonstration will involve the combination of two soil heating technologies (resistive and dielectric) with a vacuum vapor extraction system and will occur during the summer of 1994

  12. SARS and Population Health Technology

    OpenAIRE

    Eysenbach, Gunther

    2003-01-01

    The recent global outbreak of SARS (severe acute respiratory syndrome) provides an opportunity to study the use and impact of public health informatics and population health technology to detect and fight a global epidemic. Population health technology is the umbrella term for technology applications that have a population focus and the potential to improve public health. This includes the Internet, but also other technologies such as wireless devices, mobile phones, smart appliances, or smar...

  13. Wireless communication technology NFC

    OpenAIRE

    MÁROVÁ, Kateřina

    2014-01-01

    Aim of this bachelor thesis is to handle the issue of new wireless communication technology NFC (Near Field Communication) including a comparison of advantages and disadvantages of NFC with other wireless technologies (Bluetooth, Wi-Fi, etc.). NFC is a technology for wireless communications between different electronic devices, one of which is typically a mobile phone. Near Field Communication allows wireless communication at very short distance by approaching or enclosing two devices and can...

  14. Technology development multidimensional review for engineering and technology managers

    CERN Document Server

    Neshati, Ramin; Watt, Russell; Eastham, James

    2014-01-01

    Developing new products, services, systems, and processes has become an imperative for any firm expecting to thrive in today’s fast-paced and hyper-competitive environment.  This volume integrates academic and practical insights to present fresh perspectives on new product development and innovation, showcasing lessons learned on the technological frontier.  The first part emphasizes decision making.  The second part focuses on technology evaluation, including cost-benefit analysis, material selection, and scenarios. The third part features in-depth case studies to present innovation management tools, such as customer needs identification, technology standardization, and risk management. The fourth part highlights important international trends, such as globalization and outsourcing. Finally the fifth part explores social and political aspects.

  15. 40 CFR 142.307 - What terms and conditions must be included in a small system variance?

    Science.gov (United States)

    2010-07-01

    ... that may affect proper and effective operation and maintenance of the technology; (2) Monitoring... effective installation, operation and maintenance of the applicable small system variance technology in... health, which may include: (i) Public education requirements; and (ii) Source water protection...

  16. Assistive technology evaluations: Remote-microphone technology for children with Autism Spectrum Disorder.

    Science.gov (United States)

    Schafer, Erin C; Wright, Suzanne; Anderson, Christine; Jones, Jessalyn; Pitts, Katie; Bryant, Danielle; Watson, Melissa; Box, Jerrica; Neve, Melissa; Mathews, Lauren; Reed, Mary Pat

    The goal of this study was to conduct assistive technology evaluations on 12 children diagnosed with Autism Spectrum Disorder (ASD) to evaluate the potential benefits of remote-microphone (RM) technology. A single group, within-subjects design was utilized to explore individual and group data from functional questionnaires and behavioral test measures administered, designed to assess school- and home-based listening abilities, once with and once without RM technology. Because some of the children were unable to complete the behavioral test measures, particular focus was given to the functional questionnaires completed by primary teachers, participants, and parents. Behavioral test measures with and without the RM technology included speech recognition in noise, auditory comprehension, and acceptable noise levels. The individual and group teacher (n=8-9), parent (n=8-9), and participant (n=9) questionnaire ratings revealed substantially less listening difficulty when RM technology was used compared to the no-device ratings. On the behavioral measures, individual data revealed varied findings, which will be discussed in detail in the results section. However, on average, the use of the RM technology resulted in improvements in speech recognition in noise (4.6dB improvement) in eight children, higher auditory working memory and comprehension scores (12-13 point improvement) in seven children, and acceptance of poorer signal-to-noise ratios (8.6dB improvement) in five children. The individual and group data from this study suggest that RM technology may improve auditory function in children with ASD in the classroom, at home, and in social situations. However, variability in the data and the inability of some children to complete the behavioral measures indicates that individualized assistive technology evaluations including functional questionnaires will be necessary to determine if the RM technology will be of benefit to a particular child who has ASD. Copyright

  17. Technology Strategy for 'Environmental Technology for the Future'; Technology Target Areas; TTA1 - environmental technology for the future

    Energy Technology Data Exchange (ETDEWEB)

    2007-07-01

    The OG21 Technology Target Area 1 (TTA 1) group has produced a strategy for 'Environmental Technology for the Future'. A key aim of this work is to ensure that the operators on the Norwegian Continental Shelf (NCS) remain in a leading position with respect to environmental performance, while contributing to optimised resource recovery and value creation. This strategy focuses on environmental technology, which includes hardware, methods, software and knowledge. The TTA 1 group has agreed on a common vision: 'Norwegian oil and gas activities shall be leading in environmental performance, and Norway shall have the world leading knowledge and technology cluster within environmental technologies to support the zero harmful impact goals of the oil and gas industry.' Priorities have been made with emphasis on gaps that are considered most important to close and that will benefit from public research and development funding either for initialisation (primarily via the Petromaks and Climit programs) or acceleration (via Petromaks / Climit and particularly Demo 2000 where demonstration or piloting is required). The priorities aim to avoid technology gaps that are expected to be closed adequately through existing projects / programs or which are covered in other TTA strategies. The priority areas as identified are: Environmental impact and risk identification / quantification for new areas: Make quality assured environmental baseline data available on the web. Develop competence necessary to quantify and monitor the risks and risk reductions to the marine environment in new area ecosystems; Carbon capture and storage: Quantify environmental risks and waste management issues associated with bi-products from carbon capture processes and storage solutions. Develop and demonstrate effective carbon storage risk management, monitoring and mitigation technologies. Develop more cost and energy efficient power-from-shore solutions to reduce / eliminate CO{sub 2

  18. Riding the Technology Wave.

    Science.gov (United States)

    Malan, Pierre

    This paper presents an overview of information technology development. The first section sets the scene, comparing the first WAN (Wide Area Network) and Intel processor to current technology. The birth of the microcomputer is described in the second section, including historical background on semiconductors, microprocessors, and the microcomputer.…

  19. Pilot demonstrations of arsenic removal technologies.

    Energy Technology Data Exchange (ETDEWEB)

    Siegal Malcolm D.

    2004-09-01

    The Arsenic Water Technology Partnership (AWTP) program is a multi-year program funded by a congressional appropriation through the Department of Energy to develop and test innovative technologies that have the potential to reduce the costs of arsenic removal from drinking water. The AWTP members include Sandia National Laboratories, the American Water Works Association (Awwa) Research Foundation and WERC (A Consortium for Environmental Education and Technology Development). The program is designed to move technologies from bench-scale tests to field demonstrations. The Awwa Research Foundation is managing bench-scale research programs; Sandia National Laboratories is conducting the pilot demonstration program and WERC will evaluate the economic feasibility of the technologies investigated and conduct technology transfer activities. The objective of the Sandia Arsenic Treatment Technology Demonstration project (SATTD) is the field demonstration testing of both commercial and innovative technologies. The scope for this work includes: (1) Identification of sites for pilot demonstrations; (2) Accelerated identification of candidate technologies through Vendor Forums, proof-of-principle laboratory and local pilot-scale studies, collaboration with the Awwa Research Foundation bench-scale research program and consultation with relevant advisory panels; and (3) Pilot testing multiple technologies at several sites throughout the country, gathering information on: (a) Performance, as measured by arsenic removal; (b) Costs, including capital and Operation and Maintenance (O&M) costs; (c) O&M requirements, including personnel requirements, and level of operator training; and (d) Waste residuals generation. The New Mexico Environment Department has identified over 90 public water systems that currently exceed the 10 {micro}g/L MCL for arsenic. The Sandia Arsenic Treatment Technology Demonstration project is currently operating pilots at three sites in New Mexico. The cities of

  20. Technology.

    Science.gov (United States)

    Online-Offline, 1998

    1998-01-01

    Focuses on technology, on advances in such areas as aeronautics, electronics, physics, the space sciences, as well as computers and the attendant progress in medicine, robotics, and artificial intelligence. Describes educational resources for elementary and middle school students, including Web sites, CD-ROMs and software, videotapes, books,…

  1. Communication technology update and fundamentals

    CERN Document Server

    Grant, August E

    2014-01-01

    A classic now in its 14th edition, Communication Technology Update and Fundamentals is the single best resource for students and professionals looking to brush up on how these technologies have developed, grown, and converged, as well as what's in store for the future. It begins by developing the communication technology framework-the history, ecosystem, and structure-then delves into each type of technology, including everything from mass media, to computers and consumer electronics, to networking technologies. Each chapter is written by faculty and industry experts who p

  2. Handbook of display technology

    CERN Document Server

    Castellano, Joseph A

    1992-01-01

    This book presents a comprehensive review of technical and commercial aspects of display technology. It provides design engineers with the information needed to select proper technology for new products. The book focuses on flat, thin displays such as light-emitting diodes, plasma display panels, and liquid crystal displays, but it also includes material on cathode ray tubes. Displays include a large number of products from televisions, auto dashboards, radios, and household appliances, to gasoline pumps, heart monitors, microwave ovens, and more.For more information on display tech

  3. Technology Development: From Idea to Implementation - 12131

    Energy Technology Data Exchange (ETDEWEB)

    Spires, Renee H. [Savannah River Remediation (United States)

    2012-07-01

    There are good ideas and new technologies proposed every day to solve problems within the DOE complex. A process to transition a new technology from inception to the decision to launch a project with baselines is described. Examples from active technology development projects within Savannah River Remediation (SRR) will be used to illustrate the points. The process includes decision points at key junctures leading to preliminary design. At that point, normal project management tools can be employed. The technology development steps include proof-of-principle testing, scaled testing and analysis, and conceptual design. Tools are used that define the scope necessary for each step of technology development. The tools include use of the DOE technology readiness guide, Consolidated Hazards Analysis (CHA) and internal checklists developed by Savannah River Remediation. Integration with operating or planned facilities is also included. The result is a roadmap and spreadsheet that identifies each open question and how it may be answered. Performance criteria are developed that enable simple decisions to be made after the completion of each step. Conceptual design tasks should begin as the technology development continues. The most important conceptual design tasks at this point in the process include process flow diagrams (PFDs), high level Process and Instrumentation Drawings (P and IDs), and general layout drawings. These should influence the design of the scaled simulant testing. Mechanical and electrical drawings that support cost and schedule development should also be developed. An early safety control strategy developed from the CHA will also influence the cost. The combination of test results, calculations and early design output with rough order of magnitude cost and schedule information provide input into the decisions to proceed with a project and data to establish the baseline. This process can be used to mature any new technology, especially those that must be

  4. Industrial Sector Technology Use Model (ISTUM): industrial energy use in the United States, 1974-2000. Volume 4. Technology appendix. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    1979-10-01

    Volume IV of the ISTUM documentation gives information on the individual technology specifications, but relates closely with Chapter II of Volume I. The emphasis in that chapter is on providing an overview of where each technology fits into the general-model logic. Volume IV presents the actual cost structure and specification of every technology modeled in ISTUM. The first chapter presents a general overview of the ISTUM technology data base. It includes an explanation of the data base printouts and how the separate-cost building blocks are combined to derive an aggregate-technology cost. The remaining chapters are devoted to documenting the specific-technology cost specifications. Technologies included are: conventional technologies (boiler and non-boiler conventional technologies); fossil-energy technologies (atmospheric fluidized bed combustion, low Btu coal and medium Btu coal gasification); cogeneration (steam, machine drive, and electrolytic service sectors); and solar and geothermal technologies (solar steam, solar space heat, and geothermal steam technologies), and conservation technologies.

  5. 13th International Conference on Information Technology

    CERN Document Server

    2016-01-01

    This book collects articles presented at the 13th International Conference on Information Technology- New Generations, April, 2016, in Las Vegas, NV USA. It includes over 100 chapters on critical areas of IT including Web Technology, Communications, Security, and Data Mining.

  6. A new ultrasonic method to detect chemical additives in branded milk

    Indian Academy of Sciences (India)

    Abstract. A new ultrasonic method – thermoacoustic analysis – is reported for the detection of the added chemical preservatives in branded milk. The nature of variation and shift in the thermal response of the acoustic parameters specific acoustic impedance, adiabatic compressibility and Rao's specific sound velocity for ...

  7. Sadhana | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    The work reported in this paper is focused on the performance of a thermoacoustic refrigerator under various operating conditions. The experiments were conducted with various stack geometries fabricated with epoxy glass and Mylar material. Four stacks with different pore sizes are used to evaluate the performance of the ...

  8. Technology in the Public Library: Results from the 1992 PLDS Survey of Technology.

    Science.gov (United States)

    Fidler, Linda M.; Johnson, Debra Wilcox

    1994-01-01

    Discusses and compares the incorporation of technology by larger public libraries in Canada and the United States. Technology mentioned includes online public access catalogs; remote and local online database searching; microcomputers and software for public use; and fax, voice mail, and Telecommunication Devices for the Deaf and Teletype writer…

  9. Technological Developments in Networking, Education and Automation

    CERN Document Server

    Elleithy, Khaled; Iskander, Magued; Kapila, Vikram; Karim, Mohammad A; Mahmood, Ausif

    2010-01-01

    "Technological Developments in Networking, Education and Automation" includes a set of rigorously reviewed world-class manuscripts addressing and detailing state-of-the-art research projects in the following areas: Computer Networks: Access Technologies, Medium Access Control, Network architectures and Equipment, Optical Networks and Switching, Telecommunication Technology, and Ultra Wideband Communications. Engineering Education and Online Learning: including development of courses and systems for engineering, technical and liberal studies programs; online laboratories; intelligent

  10. Development of fabrication technology for CANDU advanced fuel -Development of the advanced CANDU technology-

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chang Beom; Kim, Hyeong Soo; Kim, Sang Won; Seok, Ho Cheon; Shim, Ki Seop; Byeon, Taek Sang; Jang, Ho Il; Kim, Sang Sik; Choi, Il Kwon; Cho, Dae Sik; Sheo, Seung Won; Lee, Soo Cheol; Kim, Yoon Hoi; Park, Choon Ho; Jeong, Seong Hoon; Kang, Myeong Soo; Park, Kwang Seok; Oh, Hee Kwan; Jang, Hong Seop; Kim, Yang Kon; Shin, Won Cheol; Lee, Do Yeon; Beon, Yeong Cheol; Lee, Sang Uh; Sho, Dal Yeong; Han, Eun Deok; Kim, Bong Soon; Park, Cheol Joo; Lee, Kyu Am; Yeon, Jin Yeong; Choi, Seok Mo; Shon, Jae Moon [Korea Atomic Energy Res. Inst., Taejon (Korea, Republic of)

    1994-07-01

    The present study is to develop the advanced CANDU fuel fabrication technologies by means of applying the R and D results and experiences gained from localization of mass production technologies of CANDU fuels. The annual portion of this year study includes following: 1. manufacturing of demo-fuel bundles for out-of-pile testing 2. development of technologies for the fabrication and inspection of advanced fuels 3. design and munufacturing of fuel fabrication facilities 4. performance of fundamental studies related to the development of advanced fuel fabrication technology.

  11. A model technology transfer program for independent operators: Kansas Technology Transfer Model (KTTM)

    Energy Technology Data Exchange (ETDEWEB)

    Schoeling, L.G.

    1993-09-01

    This report describes the development and testing of the Kansas Technology Transfer Model (KTTM) which is to be utilized as a regional model for the development of other technology transfer programs for independent operators throughout oil-producing regions in the US. It describes the linkage of the regional model with a proposed national technology transfer plan, an evaluation technique for improving and assessing the model, and the methodology which makes it adaptable on a regional basis. The report also describes management concepts helpful in managing a technology transfer program. The original Tertiary Oil Recovery Project (TORP) activities, upon which the KTTM is based, were developed and tested for Kansas and have proved to be effective in assisting independent operators in utilizing technology. Through joint activities of TORP and the Kansas Geological Survey (KGS), the KTTM was developed and documented for application in other oil-producing regions. During the course of developing this model, twelve documents describing the implementation of the KTTM were developed as deliverables to DOE. These include: (1) a problem identification (PI) manual describing the format and results of six PI workshops conducted in different areas of Kansas, (2) three technology workshop participant manuals on advanced waterflooding, reservoir description, and personal computer applications, (3) three technology workshop instructor manuals which provides instructor material for all three workshops, (4) three technologies were documented as demonstration projects which included reservoir management, permeability modification, and utilization of a liquid-level acoustic measuring device, (5) a bibliography of all literature utilized in the documents, and (6) a document which describes the KTTM.

  12. "First generation" automated DNA sequencing technology.

    Science.gov (United States)

    Slatko, Barton E; Kieleczawa, Jan; Ju, Jingyue; Gardner, Andrew F; Hendrickson, Cynthia L; Ausubel, Frederick M

    2011-10-01

    Beginning in the 1980s, automation of DNA sequencing has greatly increased throughput, reduced costs, and enabled large projects to be completed more easily. The development of automation technology paralleled the development of other aspects of DNA sequencing: better enzymes and chemistry, separation and imaging technology, sequencing protocols, robotics, and computational advancements (including base-calling algorithms with quality scores, database developments, and sequence analysis programs). Despite the emergence of high-throughput sequencing platforms, automated Sanger sequencing technology remains useful for many applications. This unit provides background and a description of the "First-Generation" automated DNA sequencing technology. It also includes protocols for using the current Applied Biosystems (ABI) automated DNA sequencing machines. © 2011 by John Wiley & Sons, Inc.

  13. Proceedings of the fuels technology contractors review meeting

    Energy Technology Data Exchange (ETDEWEB)

    Malone, R.D. [ed.

    1993-11-01

    The Fuels Technology Contractors Review Meeting was held November 16-18, 1993, at the Morgantown Energy Technology Center (METC) in Morgantown, West Virginia. This meeting was sponsored and hosted by METC, the Office of Fossil Energy, U.S. Department of Energy (DOE). METC periodically provides an opportunity to bring together all of the R&D participants in a DOE-sponsored contractors review meeting to present key results of their research and to provide technology transfer to the active research community and to the interested public. This meeting was previously called the Natural Gas Technology Contractors Review Meeting. This year it was expanded to include DOE-sponsored research on oil shale and tar sands and so was retitled the Fuels Technology Contractors Review Meeting. Current research activities include efforts in both natural gas and liquid fuels. The natural gas portion of the meeting included discussions of results summarizing work being conducted in fracture systems, both natural and induced; drilling, completion, and stimulation research; resource characterization; delivery and storage; gas to liquids research; and environmental issues. The meeting also included project and technology summaries on research in oil shale, tar sands, and mild coal gasification, and summaries of work in natural-gas fuel cells and natural-gas turbines. The format included oral and poster session presentations. Individual papers have been processed separately for inclusion in the Energy Science and Technology database.

  14. Poster session in instructional technology course

    Science.gov (United States)

    Diniaty, Artina; Fauzi'ah, Lina; Wulan Febriana, Beta; Arlianty, Widinda Normalia

    2017-12-01

    Instructional technology course must be studied by students in order to 1) understand the role of technology in learning, 2) capable of analyzing advantages and disadvantages of using technology in teaching, 3) capable of performing technology in teaching. A poster session in instructional technology course was performed to 1) enhance students' interest in this course and develop students' creativity. The step of this research includes: planning, implementation, and evaluation. The result showed that students' responses towards poster session in instructional technology course were good.

  15. Nuclear safeguards technology handbook

    International Nuclear Information System (INIS)

    1977-12-01

    The purpose of this handbook is to present to United States industrial organizations the Department of Energy's (DOE) Safeguards Technology Program. The roles and missions for safeguards in the U.S. government and application of the DOE technology program to industry safeguards planning are discussed. A guide to sources and products is included

  16. Technology transfer of brain-computer interfaces as assistive technology: barriers and opportunities.

    Science.gov (United States)

    Nijboer, F

    2015-02-01

    This paper provides an analysis of perspectives from different stakeholders on the state-of-the-art of BCI. Three barriers for technology transfer of BCIs as access technologies are identified. First, BCIs are developed with a narrow focus on creating a reliable technology, while a broader focus on creating a usable technology is needed. Second, the potential target group, which could benefit from BCIs as access technologies is expected to be very small. Development costs are therefore high, while reimbursements are expected to be low, which challenges the commercial viability. Third, potential target users should be much more included in the design process of BCIs to ensure that the end-products meet technical, ethical, legal and social requirements. These three issues need to be urgently addressed so that target users may benefit from this promising technology. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  17. NASA Goddard Thermal Technology Overview 2016

    Science.gov (United States)

    Butler, Dan; Swanson, Ted

    2016-01-01

    This presentation summarizes the current plans and efforts at NASA Goddard to develop new thermal control technology for anticipated future missions. It will also address some of the programmatic developments currently underway at NASA, especially with respect to the NASA Technology Development Program. The effects of the recently enacted FY 16 NASA budget, which includes a sizeable increase, will also be addressed. While funding for basic technology development is still tight, significant efforts are being made in direct support of flight programs. Thermal technology implementation on current flight programs will be reviewed, and the recent push for Cube-sat mission development will also be addressed. Many of these technologies also have broad applicability to DOD, DOE, and commercial programs. Partnerships have been developed with the Air Force, Navy, and various universities to promote technology development. In addition, technology development activities supported by internal research and development (IRAD) program and the Small Business Innovative Research (SBIR) program are reviewed in this presentation. Specific technologies addressed include; two-phase systems applications and issues on NASA missions, latest developments of electro-hydrodynamically pumped systems, Atomic Layer Deposition (ALD), Micro-scale Heat Transfer, and various other research activities.

  18. Technology transfer in CANDU marketing

    International Nuclear Information System (INIS)

    Pon, G.A.

    1982-06-01

    The author discusses how the CANDU system lends itself to technology transfer, the scope of CANDU technology transfer, and the benefits and problems associated with technology transfer. The establishment of joint ventures between supplier and client nations offers benefits to both parties. Canada can offer varying technology transfer packages, each tailored to a client nation's needs and capabilities. Such a package could include all the hardware and software necessary to develop a self-sufficient nuclear infrastructure in the client nation

  19. The great downside dilemma for risky emerging technologies

    International Nuclear Information System (INIS)

    Baum, Seth D

    2014-01-01

    Some emerging technologies promise to significantly improve the human condition, but come with a risk of failure so catastrophic that human civilization may not survive. This article discusses the great downside dilemma posed by the decision of whether or not to use these technologies. The dilemma is: use the technology, and risk the downside of catastrophic failure, or do not use the technology, and suffer through life without it. Historical precedents include the first nuclear weapon test and messaging to extraterrestrial intelligence. Contemporary examples include stratospheric geoengineering, a technology under development in response to global warming, and artificial general intelligence, a technology that could even take over the world. How the dilemma should be resolved depends on the details of each technology’s downside risk and on what the human condition would otherwise be. Meanwhile, other technologies do not pose this dilemma, including sustainable design technologies, nuclear fusion power, and space colonization. Decisions on all of these technologies should be made with the long-term interests of human civilization in mind. This paper is part of a series of papers based on presentations at the Emerging Technologies and the Future of Humanity event held at the Royal Swedish Academy of Sciences on 17 March 2014. (invited comment)

  20. Solar Energy Technologies Program Newsletter - July 2009

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-07-01

    This quarterly newsletter is intended for participants and stakeholders in the DOE Solar Program. The content includes features on technology development, market transformation, and policy analysis for solar. Highlights include solar industry updates, DOE funding opportunity announcements and awards, and national laboratory technology developments.

  1. "The Most Poisonous Force in Technology"

    Science.gov (United States)

    Carnevale, Dan

    2007-01-01

    Walt Mossberg, personal-technology columnist for "The Wall Street Journal," highlighted technology trends in his speech to a group of college presidents and other administrators. Mr. Mossberg touched a nerve when he called information-technology departments of large organizations, including colleges, "the most regressive and poisonous force in…

  2. Achieving Technological Literacy in Minnesota.

    Science.gov (United States)

    Lindstrom, Mike

    2002-01-01

    Describes how Minnesota implemented the Standards for Technological Literacy: Content for the Study of Technology. Includes the timeline, rationale, potential activities and estimated costs associated with all phases, and steps for implementing the plan: investigate, replicate, integrate, and mandate. (JOW)

  3. Nuclear safeguards technology handbook

    Energy Technology Data Exchange (ETDEWEB)

    1977-12-01

    The purpose of this handbook is to present to United States industrial organizations the Department of Energy's (DOE) Safeguards Technology Program. The roles and missions for safeguards in the U.S. government and application of the DOE technology program to industry safeguards planning are discussed. A guide to sources and products is included. (LK)

  4. Space Technology Mission Directorate Game Changing Development Program FY2015 Annual Program Review: Advanced Manufacturing Technology

    Science.gov (United States)

    Vickers, John; Fikes, John

    2015-01-01

    The Advance Manufacturing Technology (AMT) Project supports multiple activities within the Administration's National Manufacturing Initiative. A key component of the Initiative is the Advanced Manufacturing National Program Office (AMNPO), which includes participation from all federal agencies involved in U.S. manufacturing. In support of the AMNPO the AMT Project supports building and Growing the National Network for Manufacturing Innovation through a public-private partnership designed to help the industrial community accelerate manufacturing innovation. Integration with other projects/programs and partnerships: STMD (Space Technology Mission Directorate), HEOMD, other Centers; Industry, Academia; OGA's (e.g., DOD, DOE, DOC, USDA, NASA, NSF); Office of Science and Technology Policy, NIST Advanced Manufacturing Program Office; Generate insight within NASA and cross-agency for technology development priorities and investments. Technology Infusion Plan: PC; Potential customer infusion (TDM, HEOMD, SMD, OGA, Industry); Leverage; Collaborate with other Agencies, Industry and Academia; NASA roadmap. Initiatives include: Advanced Near Net Shape Technology Integrally Stiffened Cylinder Process Development (launch vehicles, sounding rockets); Materials Genome; Low Cost Upper Stage-Class Propulsion; Additive Construction with Mobile Emplacement (ACME); National Center for Advanced Manufacturing.

  5. Technology transfer - the role of AEA Technology

    International Nuclear Information System (INIS)

    Hughes, A.E.; Bullough, R.; Mason, J.P.

    1989-01-01

    This paper concentrates mostly on examples of spin offs which have arisen from the more basic research carried out by the AEA. However, it should not be inferred from this that the only examples of successful technology transfer by the AEA are of a similar, often unforeseen nature. The most outstanding example of technology transfer by the AEA must surely be that achieved through the applied research which has enabled the establishment of a successful civil nuclear power programme in the UK. The natural transfer of technology here, achieved by virtue of the unique bridging position of the AEA with respect to universities and the nuclear industry, means that its success can easily be overlooked; to do so would be a mistake. However, by including spin off examples, we hope to illustrate how the AEA has also succeeded in bridging to more difficult areas where the special relationship which it shares with the nuclear industry is absent. (author)

  6. Technologies and Capabilities in: Communications, Electronics and IT (Information Technologies)

    National Research Council Canada - National Science Library

    1998-01-01

    ... and has offices in several international cities, including Brussels and Moscow. DERA is composed of hundreds of specialist teams, each of which is an expert in its particular technology or facility...

  7. Framed by Technology

    Science.gov (United States)

    Loke, Swee-Kin

    2013-01-01

    Academic developers in New Zealand, including many specialising in educational technology, have recently been asked to demonstrate their value to the Tertiary Education Commission in view of a new funding model (Prebble, 2011). Cost-cutting measures in other countries, including the 2010 closure of UK's agency for information and communication…

  8. NASA technology applications team: Applications of aerospace technology

    Science.gov (United States)

    1993-01-01

    This report covers the activities of the Research Triangle Institute (RTI) Technology Applications Team for the period 1 October 1992 through 30 September 1993. The work reported herein was supported by the National Aeronautics and Space Administration (NASA), Contract No. NASW-4367. Highlights of the RTI Applications Team activities over the past year are presented in Section 1.0. The Team's progress in fulfilling the requirements of the contract is summarized in Section 2.0. In addition to our market-driven approach to applications project development, RTI has placed increased effort on activities to commercialize technologies developed at NASA Centers. These Technology Commercialization efforts are summarized in Section 3.0. New problem statements prepared by the Team in the reporting period are presented in Section 4.0. The Team's transfer activities for ongoing projects with the NASA Centers are presented in Section 5.0. Section 6.0 summarizes the status of four add-on tasks. Travel for the reporting period is described in Section 7.0. The RTI Team staff and consultants and their project responsibilities are listed in Appendix A. Appendix B includes Technology Opportunity Announcements and Spinoff! Sheets prepared by the Team while Appendix C contains a series of technology transfer articles prepared by the Team.

  9. Evaluative conditioning of food technologies

    DEFF Research Database (Denmark)

    Loebnitz, Natascha; Grunert, Klaus G

    2015-01-01

    Consumer attitudes play an important role in the acceptance of new technologies. The success of food innovations depends on understanding how consumers form and change attitudes toward food technologies. Earlier post hoc explanations suggest that evaluative conditioning can change consumer...... attitudes toward food technologies. The present study tests how evaluative conditioning can affect consumer acceptance of new food technologies. Furthermore, authors investigate whether evaluative conditioning is resistant to extinction after a two-month period and whether the evaluative conditioning effect...... prevails in a product-related context. Within an evaluative conditioning paradigm including between-subjects control groups in addition to standard within-subjects control conditions, participants were presented with three food technologies (conventional, enzyme, and genetic technology) paired...

  10. Using Technology in the Classroom

    Science.gov (United States)

    Boles, Stephanie Reeve

    2011-01-01

    The author describes how she has come to use technology in her classroom over the years. Her main topics include using the internet, experiencing podcasts, using technology for assessment, and recording results from science research. (Contains 3 online resources and 5 figures.)

  11. General survey of Korean advanced technology

    International Nuclear Information System (INIS)

    1984-05-01

    This book includes advanced technology, world trend of advanced technology, technological innovation study for strengthening international competitiveness, patterns of Korea industrialization and its causes, structures of Korea electronic equipment and development direction, middle and long-term prospects of home appliance, the world of computer, current situation and prospect of robot industry, homework for strengthening international competitiveness of machine industry, direction for rationalization of materials industry, current situations of technical textile, future technology of developed countries, and trend of Korea technological activities.

  12. Defining technology dependence in children and adolescents.

    Science.gov (United States)

    Spratling, Regena

    2015-05-01

    The purpose of this review was to identify current terms and definitions used to identify and describe children and adolescents who require technology. A total of 400 articles published from January 2000 through May 2012 were reviewed; 26 articles met the inclusion criteria. The review included only primary research studies that focused on a child and adolescent sample (birth to 18 years old) who required technology. Current terms and definitions used to describe children and adolescents who require technology include technology and complex care. Technology is a constant in both terminology and definitions, and it differentiates this population from the general population of children with chronic illness and special health care needs. This review highlights the need for better, more detailed descriptions of the population of children and adolescents who require technology in their daily lives. © The Author(s) 2014.

  13. Enhanced technologies for unattended ground sensor systems

    Science.gov (United States)

    Hartup, David C.

    2010-04-01

    Progress in several technical areas is being leveraged to advantage in Unattended Ground Sensor (UGS) systems. This paper discusses advanced technologies that are appropriate for use in UGS systems. While some technologies provide evolutionary improvements, other technologies result in revolutionary performance advancements for UGS systems. Some specific technologies discussed include wireless cameras and viewers, commercial PDA-based system programmers and monitors, new materials and techniques for packaging improvements, low power cueing sensor radios, advanced long-haul terrestrial and SATCOM radios, and networked communications. Other technologies covered include advanced target detection algorithms, high pixel count cameras for license plate and facial recognition, small cameras that provide large stand-off distances, video transmissions of target activity instead of still images, sensor fusion algorithms, and control center hardware. The impact of each technology on the overall UGS system architecture is discussed, along with the advantages provided to UGS system users. Areas of analysis include required camera parameters as a function of stand-off distance for license plate and facial recognition applications, power consumption for wireless cameras and viewers, sensor fusion communication requirements, and requirements to practically implement video transmission through UGS systems. Examples of devices that have already been fielded using technology from several of these areas are given.

  14. International technology catalogue: Foreign technologies to support the environmental restoration and waste management needs of the DOE complex

    International Nuclear Information System (INIS)

    Matalucci, R.V.

    1995-07-01

    This document represents a summary of 27 foreign-based environmental restoration and waste management technologies that have been screened and technically evaluated for application to the cleanup problems of the Department of Energy (DOE) nuclear weapons complex. The evaluation of these technologies was initiated in 1992 and completed in 1995 under the DOE's International Technology Coordination Program of the Office of Technology Development. A methodology was developed for conducting a country-by-country survey of several regions of the world where specific environmental technology capabilities and market potential were investigated. The countries that were selected from a rank-ordering process for the survey included: then West Germany, the Netherlands, France, Japan, Taiwan, the Czech and Slovak Republics, and the Former Soviet Union. The notably innovative foreign technologies included in this document were screened initially from a list of several hundred, and then evaluated based on criteria that examined for level of maturity, suitability to the DOE needs, and for potential cost effective application at a DOE site. Each of the selected foreign technologies that were evaluated in this effort for DOE application were subsequently matched with site-specific environmental problem units across the DOE complex using the Technology Needs Assessment CROSSWALK Report. For ease of tracking these technologies to site problem units, and to facilitate their input into the DOE EnviroTRADE Information System, they were categorized into the following three areas: (1) characterization, monitoring and sensors, (2) waste treatment and separations, and (3) waste containment. Technical data profiles regarding these technologies include title and description, performance information, development status, key regulatory considerations, intellectual property rights, institute and contact personnel, and references

  15. Technology in geriatrics.

    Science.gov (United States)

    Pilotto, Alberto; Boi, Raffaella; Petermans, Jean

    2018-03-13

    Recently, the interest of industry, government agencies and healthcare professionals in technology for aging people has increased. The challenge is whether technology may play a role in enhancing independence and quality of life and in reducing individual and societal costs of caring. Information and communication technologies, i.e. tools aimed at communicating and informing, assistive technologies designed to maintain older peoples' independence and increasing safety, and human-computer interaction technologies for supporting older people with motility and cognitive impairments as humanoid robots, exoskeletons, rehabilitation robots, service robots and companion-type are interdisciplinary topics both in research and in clinical practice. The most promising clinical applications of technologies are housing and safety to guarantee older people remaining in their own homes and communities, mobility and rehabilitation to improve mobility and gait and communication and quality of life by reducing isolation, improve management of medications and transportation. Many factors impair a broad use of technology in older age, including psychosocial and ethical issues, costs and fear of losing human interaction. A substantial lack of appropriate clinical trials to establish the clinical role of technologies to improve physical or cognitive performances and/or quality of life of subjects and their caregivers may suggest that the classical biomedical research model may not be the optimal choice to evaluate technologies in older people. In conclusion, successful technology development requires a great effort in interdisciplinary collaboration to integrate technologies into the existing health and social service systems with the aim to fit into the older adults' everyday life.

  16. Information Technology and the Third Industrial Revolution.

    Science.gov (United States)

    Fitzsimmons, Joe

    1994-01-01

    Discusses the so-called third industrial revolution, or the information revolution. Topics addressed include the progression of the revolution in the U.S. economy, in Europe, and in Third World countries; the empowering technologies, including digital switches, optical fiber, semiconductors, CD-ROM, networks, and combining technologies; and future…

  17. Status of radiation-based measurement technology

    International Nuclear Information System (INIS)

    Moon, B. S.; Lee, J. W.; Chung, C. E.; Hong, S. B.; Kim, J. T.; Park, W. M.; Kim, J. Y.

    1999-03-01

    This report describes the status of measurement equipment using radiation source and new technologies in this field. This report includes the development status in Korea together with a brief description of the technology development and application status in ten countries including France, America, and Japan. Also this report describes technical factors related to radiation-based measurement and trends of new technologies. Measurement principles are also described for the equipment that is widely used among radiation-based measurement, such as level measurement, density measurement, basis weight measurement, moisture measurement, and thickness measurement. (author). 7 refs., 2 tabs., 21 figs

  18. Emerging and Disruptive Technologies.

    Science.gov (United States)

    Kricka, Larry J

    2016-08-01

    Several emerging or disruptive technologies can be identified that might, at some point in the future, displace established laboratory medicine technologies and practices. These include increased automation in the form of robots, 3-D printing, technology convergence (e.g., plug-in glucose meters for smart phones), new point-of-care technologies (e.g., contact lenses with sensors, digital and wireless enabled pregnancy tests) and testing locations (e.g., Retail Health Clinics, new at-home testing formats), new types of specimens (e.g., cell free DNA), big biology/data (e.g., million genome projects), and new regulations (e.g., for laboratory developed tests). In addition, there are many emerging technologies (e.g., planar arrays, mass spectrometry) that might find even broader application in the future and therefore also disrupt current practice. One interesting source of disruptive technology may prove to be the Qualcomm Tricorder XPrize, currently in its final stages.

  19. Forecasting and management of technology

    National Research Council Canada - National Science Library

    Roper, A. T

    2011-01-01

    ... what the authors see as the innovations to technology management in the last 17 years: the Internet; the greater focus on group decision-making including process management and mechanism design; and desktop software that has transformed the analytical capabilities of technology managers"--Provided by publisher.

  20. Art, Technology and Nature

    DEFF Research Database (Denmark)

    Camilla Skovbjerg Paldam and Jacob Wamberg trace the Kantian heritage of radically separating art and technology, and inserting both at a distance to nature, suggesting this was a transient chapter in history. Thus, they argue, the present renegotiation between art, technology and nature is reminiscent......Since 1900, the connections between art and technology with nature have become increasingly inextricable. Through a selection of innovative readings by international scholars, this book presents the first investigation of the intersections between art, technology and nature in post-medieval times....... Transdisciplinary in approach, this volume’s 14 essays explore art, technology and nature’s shifting constellations that are discernible at the micro level and as part of a larger chronological pattern. Included are subjects ranging from Renaissance wooden dolls, science in the Italian art academies, and artisanal...

  1. 2017 Annual Technology Baseline

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Wesley J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Hand, M. M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Eberle, Annika [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Beiter, Philipp C [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kurup, Parthiv [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Turchi, Craig S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Feldman, David J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Margolis, Robert M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Augustine, Chad R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Maness, Michael [Formerly NREL; O' Connor, Patrick [Oak Ridge National Laboratory

    2018-03-26

    Consistent cost and performance data for various electricity generation technologies can be difficult to find and may change frequently for certain technologies. With the Annual Technology Baseline (ATB), the National Renewable Energy Laboratory annually provides an organized and centralized set of such cost and performance data. The ATB uses the best information from the Department of Energy national laboratories' renewable energy analysts as well as information from the Energy Information Administration for fuel-based technologies. The ATB has been reviewed by experts and it includes the following electricity generation technologies: land-based wind, offshore wind, utility-scale solar photovoltaics (PV), commercial-scale solar PV, residential-scale solar PV, concentrating solar power, geothermal power, hydropower, coal, natural gas, nuclear, and conventional biopower. This webinar presentation introduces the 2017 ATB.

  2. Mobile Technology for the Practice of Pathology.

    Science.gov (United States)

    Hartman, Douglas J

    2016-03-01

    Recently, several technological advances have been introduced to mobile phones leading some people to refer to them as "smartphones." These changes have led to widespread consumer adoption. A similar adoption has occurred within the medical field and this revolution is changing the practice of medicine, including pathology. Several mobile applications have been published for dermatology, orthopedics, ophthalmology, neurosurgery, and clinical pathology. The applications are wide ranging, including mobile technology to increase patient engagement, self-monitoring by patients, clinical algorithm calculation, facilitation between experts to resource-poor environments. These advances have been received with mixed reviews. For anatomic pathology, mobile technology applications can be broken into 4 broad categories: (a) educational uses, (b) microscope with mobile phone, (c) mobile phone as microscope/acquisition device, and (d) miscellaneous. Using a mobile phone as an acquisition device paired with a microscope seems to be the most interesting current application because of the need for expert consultation with resource-poor environments. However, several emerging uses for mobile technology may become more prominent as the technology matures including image analysis, alternative light sources, and increased opportunities for clinician and patient engagement. The flexibility represented by mobile technology represents a burgeoning field in pathology informatics.

  3. Optics and communication technology major of physics undergraduate degree at King Mongkut's Institute of Technology Ladkrabang

    Science.gov (United States)

    Buranasiri, Prathan

    2014-09-01

    A physics undergraduate degree major in optics and communication technology has been offered at King Mongkut's Institute of Technology Ladkrabang (KMITL), Bangkok, Thailand. There are nine required three credit hour courses including two laboratory courses plus a number of selections in optics and communication based technology courses. For independent thinking and industrial working skills, nine credit hours of research project, practical training or overseas studies are included for selection in the final semester. Students are encouraged to participate in international conferences and professional organizations. Recently the program, with support from SPIE and OSA, has organized its first international conference on photonic solutions 2013 (ICPS 2013).

  4. NASA Goddard Thermal Technology Overview 2017

    Science.gov (United States)

    Butler, Dan; Swanson, Ted

    2017-01-01

    This presentation summarizes the current plans and efforts at NASA Goddard to develop new thermal control technology for anticipated future missions. It will also address some of the programmatic developments currently underway at NASA, especially with respect to the NASA Technology Development Program. The effects of the recently enacted FY 17 NASA budget, which includes a sizeable increase, will also be addressed. While funding for basic technology development is still tight, significant efforts are being made in direct support of flight programs. Thermal technology Implementation on current flight programs will be reviewed, and the recent push for CubeSat mission development will also be addressed. Many of these technologies also have broad applicability to DOD (Dept. of Defense), DOE (Dept. of the Environment), and commercial programs. Partnerships have been developed with the Air Force, Navy, and various universities to promote technology development. In addition, technology development activities supported by internal research and development (IRAD) program and the Small Business Innovative Research (SBIR) program are reviewed in this presentation. Specific technologies addressed include; two-phase systems applications and issues on NASA missions, latest developments of electro-hydrodynamically pumped systems, Atomic Layer Deposition (ALD), Micro-scale Heat Transfer, and various other research activities.

  5. Energy and Technology Review

    Energy Technology Data Exchange (ETDEWEB)

    Bookless, W.A.; McElroy, L.; Wheatcraft, D.; Middleton, C.; Shang, S. [eds.

    1994-10-01

    Two articles are included: the industrial computing initiative, and artificial hip joints (applying weapons expertise to medical technology). Three research highlights (briefs) are included: KEN project (face recognition), modeling groundwater flow and chemical migration, and gas and oil national information infrastructure.

  6. Energy and Technology Review

    International Nuclear Information System (INIS)

    Bookless, W.A.; McElroy, L.; Wheatcraft, D.; Middleton, C.; Shang, S.

    1994-10-01

    Two articles are included: the industrial computing initiative, and artificial hip joints (applying weapons expertise to medical technology). Three research highlights (briefs) are included: KEN project (face recognition), modeling groundwater flow and chemical migration, and gas and oil national information infrastructure

  7. Energy Technology.

    Science.gov (United States)

    Eaton, William W.

    Reviewed are technological problems faced in energy production including locating, recovering, developing, storing, and distributing energy in clean, convenient, economical, and environmentally satisfactory manners. The energy resources of coal, oil, natural gas, hydroelectric power, nuclear energy, solar energy, geothermal energy, winds, tides,…

  8. What's technology cooking up? A systematic review of the use of technology in adolescent food literacy programs.

    Science.gov (United States)

    Wickham, Catherine A; Carbone, Elena T

    2018-06-01

    Over one-third of adolescents are overweight or obese. Food literacy (FL), the ability to plan and manage, select, prepare, and eat healthy foods, is a contemporary concept that provides a mechanism to understand the relationship between food-related knowledge and skills and dietary intake. Innovative interventions which focus on the core concepts of FL and include generationally appropriate technology have the potential to provide positive impact on the dietary habits of adolescents. This systematic review followed PRISMA guidelines and employed the Downs and Black criteria for rating studies. Titles and abstracts of 545 articles were collected and reviewed from 13 electronic databases. Studies were selected if they were peer-reviewed, included adolescents 12-19 years-old, incorporated concepts related to FL, and employed technology as part of the intervention. Eight studies, six randomized controlled trials (RCT) and two interventions without controls were included. Seven of the interventions used Internet or web-based platforms to access program components and all RCTs incorporated game elements. Studies included between two and four constructs of FL. All reported positive changes in food intake with five reporting significant positive pre- and post-intervention changes. Few technology-driven FL-related studies exist within the literature. Although all studies reported improvements in dietary intake, due to variation in program design, delivery, and evaluation it is difficult to tease out the effect of the technology component. Continued research is needed to: 1) determine the degree to which FL should be included in interventions to effect a positive change on dietary intake; 2) develop adolescent-specific FL measures to more appropriately evaluate changes in knowledge, food-related skills, and dietary intake; and 3) design technology-driven interventions so that technology components can be analyzed separately from other program elements. Copyright © 2018

  9. Human Spaceflight Technology Needs - A Foundation for JSC's Technology Strategy

    Science.gov (United States)

    Stecklein, Jonette M.

    2013-01-01

    Human space exploration has always been heavily influenced by goals to achieve a specific mission on a specific schedule. This approach drove rapid technology development, the rapidity of which adds risks as well as provides a major driver for costs and cost uncertainty. The National Aeronautics and Space Administration (NASA) is now approaching the extension of human presence throughout the solar system by balancing a proactive yet less schedule-driven development of technology with opportunistic scheduling of missions as the needed technologies are realized. This approach should provide cost effective, low risk technology development that will enable efficient and effective manned spaceflight missions. As a first step, the NASA Human Spaceflight Architecture Team (HAT) has identified a suite of critical technologies needed to support future manned missions across a range of destinations, including in cis-lunar space, near earth asteroid visits, lunar exploration, Mars moons, and Mars exploration. The challenge now is to develop a strategy and plan for technology development that efficiently enables these missions over a reasonable time period, without increasing technology development costs unnecessarily due to schedule pressure, and subsequently mitigating development and mission risks. NASA's Johnson Space Center (JSC), as the nation s primary center for human exploration, is addressing this challenge through an innovative approach in allocating Internal Research and Development funding to projects. The HAT Technology Needs (TechNeeds) Database has been developed to correlate across critical technologies and the NASA Office of Chief Technologist Technology Area Breakdown Structure (TABS). The TechNeeds Database illuminates that many critical technologies may support a single technical capability gap, that many HAT technology needs may map to a single TABS technology discipline, and that a single HAT technology need may map to multiple TABS technology

  10. Human spaceflight technology needs-a foundation for JSC's technology strategy

    Science.gov (United States)

    Stecklein, J. M.

    Human space exploration has always been heavily influenced by goals to achieve a specific mission on a specific schedule. This approach drove rapid technology development, the rapidity of which added risks and became a major driver for costs and cost uncertainty. The National Aeronautics and Space Administration (NASA) is now approaching the extension of human presence throughout the solar system by balancing a proactive yet less schedule-driven development of technology with opportunistic scheduling of missions as the needed technologies are realized. This approach should provide cost effective, low risk technology development that will enable efficient and effective manned spaceflight missions. As a first step, the NASA Human Spaceflight Architecture Team (HAT) has identified a suite of critical technologies needed to support future manned missions across a range of destinations, including in cis-lunar space, near earth asteroid visits, lunar exploration, Mars moons, and Mars exploration. The challenge now is to develop a strategy and plan for technology development that efficiently enables these missions over a reasonable time period, without increasing technology development costs unnecessarily due to schedule pressure, and subsequently mitigating development and mission risks. NASA's Johnson Space Center (JSC), as the nation's primary center for human exploration, is addressing this challenge through an innovative approach in allocating Internal Research and Development funding to projects. The HAT Technology Needs (Tech Needs) Database has been developed to correlate across critical technologies and the NASA Office of Chief Technologist Technology Area Breakdown Structure (TABS). The TechNeeds Database illuminates that many critical technologies may support a single technical capability gap, that many HAT technology needs may map to a single TABS technology discipline, and that a single HAT technology need may map to multiple TABS technology disciplines. Th

  11. Technology of serving

    OpenAIRE

    Taskov, Nako

    2013-01-01

    The book “Technology of serving” was prepared according to the curriculum and it is intended for students at the faculty of tourism and business logistics in republic of Macedonia In its contents on the subject of Technology of serving it includes the following - the rooms for serving, the types of catering objects in which food and beverages are served, professional serving staff, equipment and inventory for serving, card selection services in serving .,getting to know drin...

  12. Technology: Trigger for Change in Reference Librarianship.

    Science.gov (United States)

    Hallman, Clark N.

    1990-01-01

    Discussion of the influence of technological developments on social change focuses on the effects of information technology on academic reference librarianship. Highlights include reference skills; electronic resources; microcomputer technology; online catalogs; interaction and communication with users; the need to teach information skills; and…

  13. Intelligent Decision Technologies : Proceedings of the 4th International Conference on Intelligent Decision Technologies

    CERN Document Server

    Watanabe, Toyohide; Phillips-Wren, Gloria; Howlett, Robert; Jain, Lakhmi

    2012-01-01

    The Intelligent Decision Technologies (IDT) International Conference encourages an interchange of research on intelligent systems and intelligent technologies that enhance or improve decision making. The focus of IDT is interdisciplinary and includes research on all aspects of intelligent decision technologies, from fundamental development to real applications. IDT has the potential to expand their support of decision making in such areas as finance, accounting, marketing, healthcare, medical and diagnostic systems, military decisions, production and operation, networks, traffic management, crisis response, human-machine interfaces, financial and stock market monitoring and prediction, and robotics. Intelligent decision systems implement advances in intelligent agents, fuzzy logic, multi-agent systems, artificial neural networks, and genetic algorithms, among others.  Emerging areas of active research include virtual decision environments, social networking, 3D human-machine interfaces, cognitive interfaces,...

  14. New technologies in contraception

    OpenAIRE

    Rowlands, Sam

    2009-01-01

    New technologies in both reversible contraception and sterilisation are described. The review includes recent advances in the development of oral contraception, emergency contraception, injectable contraception, vaginal rings, subdermal implants, transdermal contraception, intrauterine devices, spermicides and barrier methods. It also covers methods of transcervical female sterilisation and more easily reversible male sterilisation. The emphasis is on the technology and its safety and effecti...

  15. Aging well with smart technology.

    Science.gov (United States)

    Cheek, Penny; Nikpour, Linda; Nowlin, Heather D

    2005-01-01

    As baby-boomers age, the need for long-term nursing care services increases. In the future, there will simply not be enough long-term care facilities to accommodate all of these patients. In addition, many people prefer to grow old at home, a concept known as aging-in-place. Smart home technology facilities aging-in-place by assisting patients with emergency assistance, fall prevention/detection, reminder systems, medication administration and assistance for those with hearing, visual or cognitive impairments. Benefits include making aging-in-place a reality, continuous monitoring, and improved psychosocial effects. Concerns of this technology include cost, availability of technology, retrofitting complications, and potential inappropriate use of the technology. Overall, the concept of smart homes is gaining in popularity and will expand the role of the nurse in the future. It is important for all nurses to understand how their practices will be transformed as smart homes become a reality for the aging population.

  16. Nuclear Reactors and Technology; (USA)

    Energy Technology Data Exchange (ETDEWEB)

    Cason, D.L.; Hicks, S.C. (eds.)

    1991-01-01

    Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database (EDB) during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency's Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on EDB and Nuclear Science Abstracts (NSA) database. Current information, added daily to EDB, is available to DOE and its contractors through the DOE integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user's needs.

  17. Technology development life cycle processes.

    Energy Technology Data Exchange (ETDEWEB)

    Beck, David Franklin

    2013-05-01

    This report and set of appendices are a collection of memoranda originally drafted in 2009 for the purpose of providing motivation and the necessary background material to support the definition and integration of engineering and management processes related to technology development. At the time there was interest and support to move from Capability Maturity Model Integration (CMMI) Level One (ad hoc processes) to Level Three. As presented herein, the material begins with a survey of open literature perspectives on technology development life cycles, including published data on %E2%80%9Cwhat went wrong.%E2%80%9D The main thrust of the material presents a rational expose%CC%81 of a structured technology development life cycle that uses the scientific method as a framework, with further rigor added from adapting relevant portions of the systems engineering process. The material concludes with a discussion on the use of multiple measures to assess technology maturity, including consideration of the viewpoint of potential users.

  18. Terahertz antenna technology for space applications

    CERN Document Server

    Choudhury, Balamati; Jha, Rakesh Mohan

    2016-01-01

    This book explores the terahertz antenna technology towards implementation of compact, consistent and cheap terahertz sources, as well as the high sensitivity terahertz detectors. The terahertz EM band provides a transition between the electronic and the photonic regions thus adopting important characteristics from these regimes. These characteristics, along with the progress in semiconductor technology, have enabled researchers to exploit hitherto unexplored domains including satellite communication, bio-medical imaging, and security systems. The advances in new materials and nanostructures such as graphene will be helpful in miniaturization of antenna technology while simultaneously maintaining the desired output levels. Terahertz antenna characterization of bandwidth, impedance, polarization, etc. has not yet been methodically structured and it continues to be a major research challenge. This book addresses these issues besides including the advances of terahertz technology in space applications worldwide,...

  19. Economic aspects of advanced energy technologies

    International Nuclear Information System (INIS)

    Ramakumar, R.; Rodriguez, A.P.; Venkata, S.S.

    1993-01-01

    Advanced energy technologies span a wide variety of resources, techniques, and end-user requirements. Economic considerations are major factors that shape their harnessing and utilization. A discussion of the basic factors in the economic arena is presented, with particular emphasis on renewable energy technologies--photovoltaics, solar-thermal, wind-electric conversion, biomass utilization, hydro, and tidal and wave energy systems. The following are essential to determine appropriate energy system topologies: proper resource-need matching with an eye on the quality of energy requirements, integrated use of several resources and technologies, and a comprehensive consideration which includes prospecting, collection, conversion, transportation, distribution, storage and reconversion, end use, and subsequent waste management aspects. A few case studies are included to apprise the reader of the status of some of the key technologies and systems

  20. Analysis of technological innovation in Danish wind turbine industry - including the Test Station for Windturbines dual roll as research institution and certification authority

    International Nuclear Information System (INIS)

    Dannemand Andersen, P.

    1993-01-01

    The overall aim of this thesis is to examine the interactions between the Danish wind turbine industry and the Test Station for Wind Turbines. Because these interactions are concerning technological innovation, it follows that the innovation processes within the enterprises must be analyzed and modelled. The study is carried out as an iterative model-developing process using case study methods. The findings from some less structured interviews are discussed with literature and forms a basis for models and new interviews. The thesis is based on interviews with 20 R and D engineers in the Danish wind turbine industry, 7 engineers at The Test Station and 7 people involved in wind power abroad (American and British). The theoretical frame for this thesis is sociology/organizational theory and industrial engineering. The thesis consists of five main sections, dealing with technology and knowledge, innovation processes, organizational culture, innovation and interaction between the Test Station's research activities and the companies' innovation processes, and finally interaction through the Test Stations certification activity. First a taxonomy for technology and knowledge is established in order to clarify what kind of technology the interactions are all about, and what kind of knowledge is transferred during the interactions. This part of the thesis also contains an analysis of the patents drawn by the Danish wind turbine industry. The analysis shows that the Danish wind turbine industry do not use patents. Instead the nature of the technology and the speed of innovation are used to protect the industry's knowledge. (EG) (192 refs.)

  1. In-situ and on-site technologies; An overview

    Energy Technology Data Exchange (ETDEWEB)

    Freestone, F J [Technical Support Branch, ORD, RREL, U.S. EPA, Edison, New Jersey (US)

    1990-01-01

    A broad analysis of and perspective on the characteristics and measured performance of in-situ and on-site treatment technologies available for remediation of contaminated soils, groundwater and associated debris at hazardous waste sites. Included in the analysis is information from U.S. and European sources. Available data are appended from nine recently completed field demonstrations from the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) program. The most frequently applied technology areas appear to be on-site thermal treatment for organics, on-site and in-situ solidification/stabilization technologies for most inorganics and metals, traditional on-site water treatment techniques, and soil vapor extraction for volatile organic compounds. Rapidly developing areas include bioremediation technologies, and concentration technologies. Two of the weakest areas include materials handling for such situations as excavating buried drums and soils with volatiles safely, and performing physical and chemical site characterization using technology-sensitive parameters. An area worthy of international cooperatin is that of performing benchscale screening and treatability studies, including the specification of key parameters needing measurement, techniques for such measurement and for interpretation, storage and retrieval of resulting data. We are in the process of evaluating existing treatability study data on soils and debris, and will be installing that data onto an on-line information system available to the public world-wide. (AB) 10 refs.

  2. The Virtual Learning Commons: An Emerging Technology for Learning About Emerging Technologies

    Science.gov (United States)

    Pennington, D. D.; Del Rio, N.; Fierro, C.; Gandara, A.; Garcia, A.; Garza, J.; Giandoni, M.; Ochoa, O.; Padilla, E.; Salamah, S.

    2013-12-01

    The Virtual Learning Commons (VLC), funded by the National Science Foundation Office of Cyberinfrastructure CI-Team Program, is a combination of semantic, visualization, and social media tools that support knowledge sharing and innovation across research disciplines. The explosion of new scientific tools and techniques challenges the ability of researchers to be aware of emerging technologies that might benefit them. Even when aware, it can be difficult to understand enough about emerging technologies to become potential adopters or re-users. Often, emerging technologies have little documentation, especially about the context of their use. The VLC tackles this challenge by providing mechanisms for individuals and groups of researchers to collectively organize Web resources through social bookmarking, and engage each other around those collections in order to a) learn about potentially relevant technologies that are emerging; and b) get feedback from other researchers on innovative ideas and designs. Concurrently, developers of emerging technologies can learn about potential users and the issues they encounter, and they can analyze the impact of their tools on other projects. The VLC aims to support the 'fuzzy front end' of innovation, where novel ideas emerge and there is the greatest potential for impact on research design. It is during the fuzzy front end that conceptual collisions across disciplines and exposure to diverse perspectives provide opportunity for creative thinking that can lead to inventive outcomes. This presentation will discuss the innovation theories that have informed design of the VLC, and hypotheses about the flow of information in virtual settings that can enable the process of innovation. The presentation will include a brief demonstration of key capabilities within the VLC that enable learning about emerging technologies, including the technologies that are presented in this session.

  3. Agricultural Technology, Risk, and Gender

    DEFF Research Database (Denmark)

    Arndt, Channing; Tarp, Finn

    2000-01-01

    Interactions between agricultural technology improvements, risk-reducing behavior, and gender roles in agricultural production in Mozambique are examined. The analysis employs a computable general equilibrium (CGE) model that explicitly incorporates key features of the economy. These include......: detailed accounting of marketing margins, home consumption, risk, and gender roles in agricultural production. Our results show that agricultural technology improvements benefit both male and female occupants of rural households. Due to economic interactions, agricultural technology improvements...

  4. Mobile technologies for every library

    CERN Document Server

    Gleason, Ann Whitney

    2015-01-01

    If you are wondering what mobile technology adoption means for your library or how to get started, Mobile Technologies for Every Library will answer your questions! This book will detail the opportunities and pitfalls in using mobile technology in libraries. It will also address platforms, options, security, and best practices for starting new mobile services programs or improving existing services. Gleason previews many useful apps for libraries. Web links and resources are also included.

  5. Strategy of technology and innovation

    International Nuclear Information System (INIS)

    Kim, Yeon Min

    1998-10-01

    This book introduces strategy of technology and innovation which includes design and development of strategy of technology, performance of strategy of technology and building and practice of strategy of development. The contents of this book are form of industrial innovation, act in strategy, advantage of technical innovation, new perspective of studying and innovation, alliance with competitor, cost of transmission and innovation, learning cycle of new product and power of consistency of product.

  6. Alternative oxidation technologies for organic mixed waste

    International Nuclear Information System (INIS)

    Borduin, L.C.; Fewell, T.

    1998-01-01

    The Mixed Waste Focus Area (MWFA) is currently supporting the development and demonstration of several alternative oxidation technology (AOT) processes for treatment of combustible mixed low-level wastes. AOTs have been defined as technologies that destroy organic material without using open-flame reactions. AOTs include both thermal and nonthermal processes that oxidize organic wastes but operate under significantly different physical and chemical conditions than incinerators. Nonthermal processes currently being studied include Delphi DETOX and acid digestion at the Savannah River Site (SRS), and direct chemical oxidation at Lawrence Livermore National Laboratory (LLNL). All three technologies are at advanced stages of development or are entering the demonstration phase. Nonflame thermal processes include catalytic chemical oxidation, which is being developed and deployed at Lawrence Berkeley National Laboratory (LBNL), and steam reforming, a commercial process being supported by the Department of Energy (DOE). Although testing is complete on some AOT technologies, most require additional support to complete some or all of the identified development objectives. Brief descriptions, status, and planned paths forward for each of the technologies are presented

  7. Exploration of an Optimal Policy for Water Resources Management Including the Introduction of Advanced Sewage Treatment Technologies in Zaozhuang City, China

    Directory of Open Access Journals (Sweden)

    Gengyu He

    2016-12-01

    Full Text Available Water shortage and water pollution are important factors restricting sustainable social and economic development. As a typical coal resource-exhausted city and a node city of the South-to-North Water Transfer East Route Project in China, Zaozhuang City’s water resources management faces multiple constraints such as transformation of economic development, restriction of groundwater exploitation, and improvement of water environment. In this paper, we develop a linear optimization model by input–output analysis to study water resources management with the introduction of three advanced sewage treatment technologies for pollutant treatment and reclaimed water production. The simulation results showed that from 2014 to 2020, Zaozhuang City will realize an annual GDP growth rate of 7.1% with an annual chemical oxygen demand (COD emissions reduction rate of 5.5%. The proportion of primary industry, secondary industry, and tertiary industry would be adjusted to 5.6%, 40.8%, and 53.6%, respectively. The amount of reclaimed water supply could be increased by 91% and groundwater supply could be decreased by 6%. Based on the simulation, this model proposes a scientific reference on water resources management policies, including water environment control, water supply plan, and financial subsidy, to realize the sustainable development of economy and water resources usage.

  8. Data-Base Software For Tracking Technological Developments

    Science.gov (United States)

    Aliberti, James A.; Wright, Simon; Monteith, Steve K.

    1996-01-01

    Technology Tracking System (TechTracS) computer program developed for use in storing and retrieving information on technology and related patent information developed under auspices of NASA Headquarters and NASA's field centers. Contents of data base include multiple scanned still images and quick-time movies as well as text. TechTracS includes word-processing, report-editing, chart-and-graph-editing, and search-editing subprograms. Extensive keyword searching capabilities enable rapid location of technologies, innovators, and companies. System performs routine functions automatically and serves multiple users.

  9. NAND flash memory technologies

    CERN Document Server

    Aritome, Seiichi

    2016-01-01

    This book discusses basic and advanced NAND flash memory technologies, including the principle of NAND flash, memory cell technologies, multi-bits cell technologies, scaling challenges of memory cell, reliability, and 3-dimensional cell as the future technology. Chapter 1 describes the background and early history of NAND flash. The basic device structures and operations are described in Chapter 2. Next, the author discusses the memory cell technologies focused on scaling in Chapter 3, and introduces the advanced operations for multi-level cells in Chapter 4. The physical limitations for scaling are examined in Chapter 5, and Chapter 6 describes the reliability of NAND flash memory. Chapter 7 examines 3-dimensional (3D) NAND flash memory cells and discusses the pros and cons in structure, process, operations, scalability, and performance. In Chapter 8, challenges of 3D NAND flash memory are dis ussed. Finally, in Chapter 9, the author summarizes and describes the prospect of technologies and market for the fu...

  10. Technology transfer at TRIUMF

    International Nuclear Information System (INIS)

    Gardner, P.

    1994-06-01

    TRIUMF is Canada's major national research centre for sub-atomic physics. For the past five or six years, there has been an increasing emphasis on commercializing the technology that has emanated from the scientific research at the facility. This emphasis on technology transfer reflects a national policy trend of the Canadian federal government, which is the funding source for the majority of the research performed at TRIUMF. In TRIUMF's case, however, the initiative and funding for the commercialization office came from the provincial, or local government. This paper will describe the evolution of technology transfer at the TRIUMF facility, identifying the theory, policies and practical procedures that have been developed and followed. It will also include TRIUMF's experiences in finding exploitable technologies, protecting those technologies, and locating and linking with suitable industry partners to commercialize the technologies. There will be a discussion of resource allocation, and how TRIUMF has endeavoured to establish a portfolio of projects of assorted risks and expected returns. (author). 15 refs

  11. In the Presence of Technology

    DEFF Research Database (Denmark)

    Nortvig, Anne-Mette

    2013-01-01

    Abstract: In a hybrid synchronous classroom that includes both on line and on campus students, technology plays a big part in the teaching. This paper attempts to analyse and discuss how the transparency of technology affects opportunities for the students to interact and for the teacher to be pr...

  12. Technology-Rich Schools Up Close

    Science.gov (United States)

    Levin, Barbara B.; Schrum, Lynne

    2013-01-01

    This article observes that schools that use technology well have key commonalities, including a project-based curriculum and supportive, distributed leadership. The authors' research into tech-rich schools revealed that schools used three strategies to integrate technology successfully. They did so by establishing the vision and culture,…

  13. The Kyoto Mechanisms and Technological Innovation

    DEFF Research Database (Denmark)

    Lund, Henrik

    2003-01-01

    Climate change response, including implementation of the Kyoto targets as the first step, calls for technological innovation of future sustainable energy systems. One of the important agreements in several declarations, including the Kyoto protocol, has been to promote and coordinate...... the collaboration between the countries in the necessary technological development. The paper encourage that the Kyoto mechanisms will be used for acceleration of the necessary technical innovation in Denmark....

  14. Technology Roadmapping for Waste Management

    International Nuclear Information System (INIS)

    Bray, O.

    2003-01-01

    Technology roadmapping can be an effective strategic technology planning tool. This paper describes a process for customizing a generic technology roadmapping process. Starting with a generic process reduces the learning curve and speeds up the roadmap development. Similarly, starting with a generic domain model provides leverage across multiple applications or situations within the domain. A process that combines these two approaches facilitates identifying technology gaps and determining common core technologies that can be reused for multiple applications or situations within the domain. This paper describes both of these processes and how they can be integrated. A core team and a number of technology working groups develop the technology roadmap, which includes critical system requirements and targets, technology areas and metrics for each area, and identifies and evaluates possible technology alternatives to recommend the most appropriate ones to pursue. A generalized waste management model, generated by considering multiple situations or applications in terms of a generic waste management model, provides the domain requirements for the technology roadmapping process. Finally, the paper discusses lessons learns from a number of roadmapping projects

  15. HEMISPHERIC CENTER FOR ENVIRONMENTAL TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    M.A. Ebadian

    1999-10-31

    The Deactivation and Decommissioning (D&D) Technology Assessment Program (TAP) was developed to provide detailed, comparable data for environmental technologies and to disseminate this data to D&D professionals in a manner that will facilitate the review and selection of technologies to perform decontamination and decommissioning. The objectives for this project include the following: Determine technology needs through review of the Site Technology Coordination Group (STCG) information and other applicable websites and needs databases; Perform a detailed review of industries that perform similar activities as those required in D&D operations to identify additional technologies; Define the technology assessment program for characterization and waste management problem sets; Define the data management program for characterization, dismantlement, and waste management problem sets; Evaluate baseline and innovative technologies under standard test conditions at Florida International University's Hemispheric Center for Environmental Technology (FIU-HCET) and other locations and collect data in the areas of performance, cost, health and safety, operations and maintenance, and primary and secondary waste generation; Continue to locate, verify, and incorporate technology performance data from other sources into the multimedia information system; and Develop the conceptual design for a dismantlement technology decision analysis tool for dismantlement technologies.

  16. Technology Learning Ratios in Global Energy Models

    International Nuclear Information System (INIS)

    Varela, M.

    2001-01-01

    The process of introduction of a new technology supposes that while its production and utilisation increases, also its operation improves and its investment costs and production decreases. The accumulation of experience and learning of a new technology increase in parallel with the increase of its market share. This process is represented by the technological learning curves and the energy sector is not detached from this process of substitution of old technologies by new ones. The present paper carries out a brief revision of the main energy models that include the technology dynamics (learning). The energy scenarios, developed by global energy models, assume that the characteristics of the technologies are variables with time. But this trend is incorporated in a exogenous way in these energy models, that is to say, it is only a time function. This practice is applied to the cost indicators of the technology such as the specific investment costs or to the efficiency of the energy technologies. In the last years, the new concept of endogenous technological learning has been integrated within these global energy models. This paper examines the concept of technological learning in global energy models. It also analyses the technological dynamics of the energy system including the endogenous modelling of the process of technological progress. Finally, it makes a comparison of several of the most used global energy models (MARKAL, MESSAGE and ERIS) and, more concretely, about the use these models make of the concept of technological learning. (Author) 17 refs

  17. Multimedia database retrieval technology and applications

    CERN Document Server

    Muneesawang, Paisarn; Guan, Ling

    2014-01-01

    This book explores multimedia applications that emerged from computer vision and machine learning technologies. These state-of-the-art applications include MPEG-7, interactive multimedia retrieval, multimodal fusion, annotation, and database re-ranking. The application-oriented approach maximizes reader understanding of this complex field. Established researchers explain the latest developments in multimedia database technology and offer a glimpse of future technologies. The authors emphasize the crucial role of innovation, inspiring users to develop new applications in multimedia technologies

  18. Mobile biometric device (MBD) technology :

    Energy Technology Data Exchange (ETDEWEB)

    Aldridge, Chris D.

    2013-06-01

    Mobile biometric devices (MBDs) capable of both enrolling individuals in databases and performing identification checks of subjects in the field are seen as an important capability for military, law enforcement, and homeland security operations. The technology is advancing rapidly. The Department of Homeland Security Science and Technology Directorate through an Interagency Agreement with Sandia sponsored a series of pilot projects to obtain information for the first responder law enforcement community on further identification of requirements for mobile biometric device technology. Working with 62 different jurisdictions, including components of the Department of Homeland Security, Sandia delivered a series of reports on user operation of state-of-the-art mobile biometric devices. These reports included feedback information on MBD usage in both operational and exercise scenarios. The findings and conclusions of the project address both the limitations and possibilities of MBD technology to improve operations. Evidence of these possibilities can be found in the adoption of this technology by many agencies today and the cooperation of several law enforcement agencies in both participating in the pilot efforts and sharing of information about their own experiences in efforts undertaken separately.

  19. DOE SNF technology development necessary for final disposal

    International Nuclear Information System (INIS)

    Hale, D.L.; Fillmore, D.L.; Windes, W.E.

    1996-01-01

    Existing technology is inadequate to allow safe disposal of the entire inventory of US Department of Energy (DOE) spent nuclear fuel (SNF). Needs for SNF technology development were identified for each individual fuel type in the diverse inventory of SNF generated by past, current, and future DOE materials production, as well as SNF returned from domestic and foreign research reactors. This inventory consists of 259 fuel types with different matrices, cladding materials, meat composition, actinide content, and burnup. Management options for disposal of SNF include direct repository disposal, possible including some physical or chemical preparation, or processing to produce a qualified waste form by using existing aqueous processes or new treatment processes. Technology development needed for direct disposal includes drying, mitigating radionuclide release, canning, stabilization, and characterization technologies. While existing aqueous processing technology is fairly mature, technology development may be needed to apply one of these processes to SNF different than for which the process was originally developed. New processes to treat SNF not suitable for disposal in its current form were identified. These processes have several advantages over existing aqueous processes

  20. Technology and international climate policy

    International Nuclear Information System (INIS)

    Clarke, Leon; Calvin, Kate; Edmonds, James A.; Kyle, Page; Wise, Marshall

    2009-01-01

    Both the nature of international climate policy architectures and the development and diffusion of new energy technologies could dramatically influence future costs of reducing global emissions of greenhouse gases. This paper explores the implications of interactions between technology availability and performance and international policy architectures for technology choice and the social cost of limiting atmospheric CO2 concentrations to 500 ppm by the year 2095. Key issues explored in the paper include the role of bioenergy production with CO2 capture and storage (CCS), overshoot concentration pathways, and the sensitivity of mitigation costs to policy and technology.

  1. Technology and international climate policy

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, Leon; Calvin, Kate; Edmonds, James A.; Kyle, Page; Wise, Marshall

    2009-05-01

    Both the nature of international climate policy architectures and the development and diffusion of new energy technologies could dramatically influence future costs of reducing global emissions of greenhouse gases. This paper explores the implications of interactions between technology availability and performance and international policy architectures for technology choice and the social cost of limiting atmospheric CO2 concentrations to 500 ppm by the year 2095. Key issues explored in the paper include the role of bioenergy production with CO2 capture and storage (CCS), overshoot concentration pathways, and the sensitivity of mitigation costs to policy and technology.

  2. Reusable Launch Vehicle Technology Program

    Science.gov (United States)

    Freeman, Delma C., Jr.; Talay, Theodore A.; Austin, R. Eugene

    1997-01-01

    Industry/NASA reusable launch vehicle (RLV) technology program efforts are underway to design, test, and develop technologies and concepts for viable commercial launch systems that also satisfy national needs at acceptable recurring costs. Significant progress has been made in understanding the technical challenges of fully reusable launch systems and the accompanying management and operational approaches for achieving a low cost program. This paper reviews the current status of the RLV technology program including the DC-XA, X-33 and X-34 flight systems and associated technology programs. It addresses the specific technologies being tested that address the technical and operability challenges of reusable launch systems including reusable cryogenic propellant tanks, composite structures, thermal protection systems, improved propulsion and subsystem operability enhancements. The recently concluded DC-XA test program demonstrated some of these technologies in ground and flight test. Contracts were awarded recently for both the X-33 and X-34 flight demonstrator systems. The Orbital Sciences Corporation X-34 flight test vehicle will demonstrate an air-launched reusable vehicle capable of flight to speeds of Mach 8. The Lockheed-Martin X-33 flight test vehicle will expand the test envelope for critical technologies to flight speeds of Mach 15. A propulsion program to test the X-33 linear aerospike rocket engine using a NASA SR-71 high speed aircraft as a test bed is also discussed. The paper also describes the management and operational approaches that address the challenge of new cost effective, reusable launch vehicle systems.

  3. Fossil energy waste management. Technology status report

    Energy Technology Data Exchange (ETDEWEB)

    Bossart, S.J.; Newman, D.A.

    1995-02-01

    This report describes the current status and recent accomplishments of the Fossil Energy Waste Management (FE WM) projects sponsored by the Morgantown Energy Technology Center (METC) of the US Department of Energy (DOE). The primary goal of the Waste Management Program is to identify and develop optimal strategies to manage solid by-products from advanced coal technologies for the purpose of ensuring the competitiveness of advanced coal technologies as a future energy source. The projects in the Fossil Energy Waste Management Program are divided into three types of activities: Waste Characterization, Disposal Technologies, and Utilization Technologies. This technology status report includes a discussion on barriers to increased use of coal by-products. Also, the major technical and nontechnical challenges currently being addressed by the FE WM program are discussed. A bibliography of 96 citations and a list of project contacts is included if the reader is interested in obtaining additional information about the FE WM program.

  4. Hanford Waste Vitrification Plant Technology Plan

    International Nuclear Information System (INIS)

    Sexton, R.A.

    1988-06-01

    The reference Hanford plan for disposal of defense high-level waste is based on waste immobilization in glass by the vitrification process and temporary vitrified waste storage at the Hanford Site until final disposal in a geologic repository. A companion document to the Hanford Waste Management Plan (HWMP) is the Draft, Interim Hanford Waste Management Technology Plan (HWMTP), which provides a description of the technology that must be developed to meet the reference waste management plan. One of the issues in the HWMTP is DST-6, Immobilization (Glass). The HWMTP includes all expense funding needed to complete the Hanford Waste Vitrification Plant (HWVP) project. A preliminary HWVP Technology Plan was prepared in 1985 as a supporting document to the HWMTP to provide a more detailed description of the technology needed to construct and operate a vitrification facility. The plan was updated and issued in 1986, and revised in 1987. This document is an annual update of the plan. The HWVP Technology Plan is limited in scope to technology that requires development or confirmation testing. Other expense-funded activities are not included. The relationship between the HWVP Technology Plan and other waste management issues addressed in the HWMTP is described in section 1.6 of this plan. 6 refs., 4 figs., 34 tabs

  5. Applied machining technology

    CERN Document Server

    Tschätsch, Heinz

    2010-01-01

    Machining and cutting technologies are still crucial for many manufacturing processes. This reference presents all important machining processes in a comprehensive and coherent way. It includes many examples of concrete calculations, problems and solutions.

  6. Ion Acoustic Microscopy

    Science.gov (United States)

    1985-07-01

    Thermal and Related Sciences, L’ Esterel, Quebec (1985), to be published in Can. J. Phys.; H. I. Ringermacher and L. Jackman , "Deep Thermoacoustic Imaging...Research System Bldg. 860 Vandenburg AFB, CA 93437 Dr. Robert V. Ieth, Chief Scientist Div. 76 Hughes Aircraft P.O. Box 902 El Segundo, CA 90245 Dr. Thomas

  7. Educational technology in care management: technological profile of nurses in Portuguese hospitals.

    Science.gov (United States)

    Landeiro, Maria José Lumini; Freire, Rosa Maria Albuquerque; Martins, Maria Manuela; Martins, Teresa Vieira; Peres, Heloísa Helena Ciqueto

    2015-12-01

    Objective To identify the technological profile of nurses in Portuguese hospitals. Method A quantitative exploratory study conducted in two hospitals in the northern region and one in the central region of Portugal. The sample was randomly selected and included 960 nurses. Results Of the participants, 420 (46.1%) used computers, 196 (23.4%) reported having knowledge about using computers for teaching, 174 (21.1%) used computers to teach, 112 (15.1%) recognized that using computers can be a technological means to supplement classroom training, 477 (61.6%) would like to receive training on using computers, and 382 (40.9%) reported self-learning of information technology. In relation to distance education, 706 (74.9%) reported they were familiar with it and 752 (76.4%) indicated an interest in participating in training using this modality. Conclusion Organizations should be mindful of the technological profile shown by this group of nurses and look for ways to introduce educational technologies in the management of care.

  8. Digital security technology simplified.

    Science.gov (United States)

    Scaglione, Bernard J

    2007-01-01

    Digital security technology is making great strides in replacing analog and other traditional security systems including CCTV card access, personal identification and alarm monitoring applications. Like any new technology, the author says, it is important to understand its benefits and limitations before purchasing and installing, to ensure its proper operation and effectiveness. This article is a primer for security directors on how digital technology works. It provides an understanding of the key components which make up the foundation for digital security systems, focusing on three key aspects of the digital security world: the security network, IP cameras and IP recorders.

  9. HEMISPHERIC CENTER FOR ENVIRONMENTAL TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    M.A. Ebadian

    1999-04-30

    The final data package has been completed for the Mississippi State University, DIAL FTP Wall Depth Removal Characterization Technology. The package has been sent to DIAL for comments. Work is progressing on completing the transfer of glove boxes and tanks from Rocky Flats to FIU-HCET for the purpose of performing size reduction technology assessments. Vendors are being identified and security measures are being put in place to meet the High Risk Property criteria required by Rocky Flats. The FIU-HCET Technology Assessment Program has been included as one of 11 verification programs across the US and Canada described in the Interstate Technology Regulatory Cooperation (ITRC) document, ''Multi-state Evaluation of Elements Important to the Verification of Remediation Technologies'', dated January 1999. FIU-HCET will also participate in a panel discussion on technology verification programs at the International Environmental Technology Expo '99.

  10. Making Technology Ready: Integrated Systems Health Management

    Science.gov (United States)

    Malin, Jane T.; Oliver, Patrick J.

    2007-01-01

    This paper identifies work needed by developers to make integrated system health management (ISHM) technology ready and by programs to make mission infrastructure ready for this technology. This paper examines perceptions of ISHM technologies and experience in legacy programs. Study methods included literature review and interviews with representatives of stakeholder groups. Recommendations address 1) development of ISHM technology, 2) development of ISHM engineering processes and methods, and 3) program organization and infrastructure for ISHM technology evolution, infusion and migration.

  11. Refolding Technologies for Antibody Fragments

    Directory of Open Access Journals (Sweden)

    Tsutomu Arakawa

    2014-05-01

    Full Text Available Refolding is one of the production technologies for pharmaceutical grade antibody fragments. Detergents and denaturants are primarily used to solubilize the insoluble proteins. The solubilized and denatured proteins are refolded by reducing the concentration of the denaturants or detergents. Several refolding technologies have been used for antibody fragments, comprising dilution, dialysis, solid phase solvent exchange and size exclusion chromatography, as reviewed here. Aggregation suppressor or folding-assisting agents, including arginine hydrochloride, ionic liquids and detergents or denaturants at low concentrations, are included in the refolding solvent to enhance refolding yield.

  12. Advanced technologies, systems, and applications

    CERN Document Server

    Avdaković, Samir

    2017-01-01

    This volume spans a wide range of technical disciplines and technologies, including complex systems, biomedical engineering, electrical engineering, energy, telecommunications, mechanical engineering, civil engineering, and computer science. The papers included in this volume were presented at the International Symposium on Innovative and Interdisciplinary Applications of Advanced Technologies (IAT), held in Neum, Bosnia and Herzegovina on June 26 and 27, 2016. This highly interdisciplinary volume is devoted to various aspects and types of systems. Systems thinking is crucial for successfully building and understanding man-made, natural, and social systems. .

  13. Patient safety and technology-driven medication

    DEFF Research Database (Denmark)

    Orbæk, Janne; Gaard, Mette; Keinicke Fabricius, Pia

    2015-01-01

    ways of educating nursing students in today's medication administration. AIM: To explore nursing students' experiences and competences with the technology-driven medication administration process. METHODS: 16 pre-graduate nursing students were included in two focus group interviews which were recorded...... for the technology-driven medication process, nursing students face difficulties in identifying and adopting best practices. The impact of using technology on the frequency, type and severity of medication errors; the technologies implications on nursing professionalism and the nurses ability to secure patient...

  14. The Kyoto mechanisms and technological innovation

    DEFF Research Database (Denmark)

    Lund, Henrik

    2006-01-01

    Climate change response, including the implementation of the Kyoto targets as the first step, calls for technological innovation of future sustainable energy systems. Based on the Danish case, this paper evaluates the type of technological change necessary. During a period of 30 years, Denmark...... countries. Consequently, the innovative technological development has changed. This paper evaluates the character of such change and makes preliminary recommendations for policies to encourage the use of the Kyoto Mechanisms as an acceleration of the necessary technological innovation....

  15. The European fusion nuclear technology effort

    International Nuclear Information System (INIS)

    Darvas, J.

    1989-01-01

    The role of fusion technology in the European fusion development strategy is outlined. The main thrust of the present fusion technology programme is responding to development needs of the Next European Torus. A smaller, but important and growing R and D effort is dealing with problems specific to the Demonstration, or Fusion Power, Reactor. The part of the programme falling under the somewhat arbitrarily defined category of 'fusion nuclear technology' is reviewed and an outlook to future activities is given. The review includes tritium technology, blanket technology and breeder materials development, technology and materials for the protection of the first wall and of other plasma facing components, remote handling technology, and safety and environmental impact studies. A few reflections are offered on the future long-term developments in fusion technology. (orig.)

  16. Current Abstracts Nuclear Reactors and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Bales, J.D.; Hicks, S.C. [eds.

    1993-01-01

    This publication Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on the Energy Science and Technology Database and Nuclear Science Abstracts (NSA) database. Current information, added daily to the Energy Science and Technology Database, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user`s needs.

  17. Clean coal technology challenges for China

    Energy Technology Data Exchange (ETDEWEB)

    Mao, J. [Tsinghua University, Beijing (China). Dept. of Thermal Engineering

    2001-01-01

    China is rich in coal reserves and also the largest coal producer and consumer in the world. Coal constitutes over 70% of the total energy consumption, some 86% of coal production is burned directly, which causes serious air pollution problems. However, based on China's specific energy structure, coal utilisation will remain the dominant means of energy usage and clean coal technology must be the way forward if the environmental problems are to be resolved. This article discusses China's Clean Coal Technology Program, its implementation, including the clean coal technologies being developed and introduced, with reference to the key R & D institutes for each of the coal-using sectors. The article is an edited version of the 2000 Robens Coal Science Lecture, delivered in London in October 2000. The China Coal Technology Program for the 9th Five-Year Plan (1996-2000) was approved in 1997. The technologies included in the Program considered in this article are in: coal washing and grading, coal briquette, coal water slurry; circulating fluidised bed technology; pressurised fluidised bed combined cycle; integrated gasification combined cycle; coal gasification, coal liquefaction and flue gas desulfurisation. 4 tabs.

  18. Offsite demonstrations for MWLID technologies

    International Nuclear Information System (INIS)

    Williams, C.; Gruebel, R.

    1995-01-01

    The goal of the Offsite Demonstration Project for Mixed Waste Landfill Integrated Demonstration (MWLID)-developed environmental site characterization and remediation technologies is to facilitate the transfer, use, and commercialization of these technologies to the public and private sector. The meet this goal, the project identified environmental restoration needs of mixed waste and/or hazardous waste landfill owners (Native American, municipal, DOE, and DoD); documenting potential demonstration sites and the contaminants present at each site; assessing the environmental regulations that would effect demonstration activities; and evaluating site suitability for demonstrating MWLID technologies at the tribal and municipal sites identified. Eighteen landfill sites within a 40.2-km radius of Sandia National Laboratories are listed on the CERCLIS Site/Event Listing for the state of New Mexico. Seventeen are not located within DOE or DoD facilities and are potential offsite MWLID technology demonstration sites. Two of the seventeen CERCLIS sites, one on Native American land and one on municipal land, were evaluated and identified as potential candidates for off-site demonstrations of MWLID-developed technologies. Contaminants potentially present on site include chromium waste, household/commercial hazardous waste, volatile organic compounds, and petroleum products. MWLID characterization technologies applicable to these sites include Magnetometer Towed Array, Cross-borehole Electromagnetic Imaging, SitePlanner trademark/PLUME, Hybrid Directional Drilling, Seamist trademark/Vadose Zone Monitoring, Stripping Analyses, and x-ray Fluorescence Spectroscopy for Heavy Metals

  19. Effects of porous insert on flame dynamics in a lean premixed swirl-stabilized combustor

    Science.gov (United States)

    Brown, Marcus; Agrawal, Ajay; Allen, James; Kornegay, John

    2016-11-01

    In this study, we investigated different methods of determining the effect a porous insert has on flame dynamics during lean premixed combustion. A metallic porous insert is used to mitigate instabilities in a swirl-stabilized combustor. Thermoacoustic instabilities are seen as negative consequences of lean premixed combustion and eliminating them is the motivation for our research. Three different diagnostics techniques with high-speed Photron SA5 cameras were used to monitor flame characteristics. Particle image velocimetry (PIV) was used to observe vortical structures and recirculation zones within the combustor. Using planar laser induced fluorescence (PLIF), we were able to observe changes in the reaction zones during instabilities. Finally, utilizing a color high-speed camera, visual images depicting a flame's oscillations during the instability were captured. Using these monitoring techniques, we are able to support the claims made in previous studies stating that the porous insert in the combustor significantly reduces the thermoacoustic instability. Funding for this research was provided by the NSF REU site Grant EEC 1358991 and NASA Grant NNX13AN14A.

  20. 2015 International Conference on Information Technology and Intelligent Transportation Systems

    CERN Document Server

    Jain, Lakhmi; Zhao, Xiangmo

    2017-01-01

    This volume includes the proceedings of the 2015 International Conference on Information Technology and Intelligent Transportation Systems (ITITS 2015) which was held in Xi’an on December 12-13, 2015. The conference provided a platform for all professionals and researchers from industry and academia to present and discuss recent advances in the field of Information Technology and Intelligent Transportation Systems. The presented information technologies are connected to intelligent transportation systems including wireless communication, computational technologies, floating car data/floating cellular data, sensing technologies, and video vehicle detection. The articles focusing on intelligent transport systems vary in the technologies applied, from basic management systems to more application systems including topics such as emergency vehicle notification systems, automatic road enforcement, collision avoidance systems and some cooperative systems. The conference hosted 12 invited speakers and over 200 part...

  1. 6. Seminar of the IIE-ININ-IMP on technological specialties. Topic 15: commercialization and technology transfer

    International Nuclear Information System (INIS)

    1992-01-01

    The document includes 9 papers presented at the 6. Seminar of the IIE-ININ-IMP (Mexico) on technological specialties in the field of commercialization and technology transfer. (Topic 15). One item was in INIS s ubject scope and a separate abstract was prepared for it

  2. The role of surgeons in identifying emerging technologies for health technology assessment.

    Science.gov (United States)

    Stafinski, Tania; Topfer, Leigh-Ann; Zakariasen, Ken; Menon, Devidas

    2010-04-01

    Health technology assessment (HTA) is a tool intended to help policy-makers decide which technologies to fund. However, given the proliferation of new technologies, it is not possible to undertake an HTA of each one before it becomes funded. Consequently, "horizon-scanning" processes have been developed to identify emerging technologies that are likely to have a substantial impact on clinical practice. Although the importance of physicians in the adoption of new technologies is well recognized, their role in horizon scanning in Canada has been limited. The purpose of this project was to pilot an approach to engage physicians, specifically surgeons, in provincial horizon-scanning activities. We invited 18 surgeons from Alberta's 2 medical schools to a horizon-scanning workshop to solicit their views on emerging technologies expected to impact surgical practice within the next 5 years and/or the importance of different attributes or characteristics of new technologies. Surgeons, regardless of specialty, identified developments designed to enhance existing minimally invasive surgical techniques, such as endoscopic, robotic and image-guided surgery. Several nonsurgical areas, including molecular genetics and nano technology, were also identified. Of the 13 technology attributes discussed, safety or risk, effectiveness and feasibility were rated as most important. Lastly, participating surgeons expressed an interest in becoming further involved in local HTA initiatives. Surgeons, as adopters and users of health technologies, represent an important and accessible information source for identifying emerging technologies for HTA. A more formal, ongoing relationship between the government, HTA and surgeons may help to optimize the use of HTA resources.

  3. Dynamics of energy technologies and global change

    International Nuclear Information System (INIS)

    Grubler, A.; Nakicenovic, N.; Victor, D.G.

    1999-01-01

    Technological choices largely determine the long-term characteristics of industrial society, including impacts on the natural environment. However, the treatment of technology in existing models that are used to project economic and environmental futures remains highly stylized. Based on work over two decades at IIASA, we present a useful typology for technology analysis and discuss methods that can be used to analyze the impact of technological changes on the global environment, especially global warming. Our focus is energy technologies, the main source of many atmospheric environmental problems. We show that much improved treatment of technology is possible with a combination of historical analysis and new modeling techniques. In the historical record, we identify characteristic 'learning rates' that allow simple quantified characterization of the improvement in cost and performance due to cumulative experience and investments. We also identify patterns, processes and timescales that typify the diffusion of new technologies in competitive markets. Technologies that are long-lived and are components of interlocking networks typically require the longest time to diffuse and co-evolve with other technologies in the network; such network effects yield high barriers to entry even for superior competitors. These simple observations allow three improvements to modeling of technological change and its consequences for global environmental change. One is that the replacement of long-lived infrastructures over time has also replaced the fuels that power the economy to yield progressively more energy per unit of carbon pollution - from coal to oil to gas. Such replacement has 'decarbonized' the global primary energy supply 0.3% per year. In contrast, most baseline projections for emissions of carbon, the chief cause of global warming, ignore this robust historical trend and show Iittle or no decarbonization. A second improvement is that by incorporating learning curves and

  4. Technology in L1

    DEFF Research Database (Denmark)

    Elf, Nikolaj Frydensbjerg; Hanghøj, Thorkild; Skaar, Håvard

    2015-01-01

    In recent decades, several Scandinavian research projects have had an explicit focus on how technology intervenes in L1 (or so-called Mother Tongue Education) practices in Swedish, Norwegian and Danish educational contexts, and how this may impact on understanding of the subject. There is currently......-of-school literacy practices. A final finding is the emphasis on teacher uncertainty regarding how and why to integrate technology within existing paradigms of the subject. This calls for further research on how technology may be justified in L1 practice, including various forms of teacher education....... no systematic overview of the documented possibilities and challenges related to the use of technology in L1. At the same time, there is terminological confusion in use of ‘technology’ and related concepts in L1. Finally, there is a general lack of critical reflection on the relation between technological...

  5. Smart storage technologies applied to fresh foods: A review.

    Science.gov (United States)

    Wang, Jingyu; Zhang, Min; Gao, Zhongxue; Adhikari, Benu

    2017-06-30

    Fresh foods are perishable, seasonal and regional in nature and their storage, transportation, and preservation of freshness are quite challenging. Smart storage technologies can online detection and monitor the changes of quality parameters and storage environment of fresh foods during storage, so that operators can make timely adjustments to reduce the loss. This article reviews the smart storage technologies from two aspects: online detection technologies and smartly monitoring technologies for fresh foods. Online detection technologies include electronic nose, nuclear magnetic resonance (NMR), near infrared spectroscopy (NIRS), hyperspectral imaging and computer vision. Smartly monitoring technologies mainly include some intelligent indicators for monitoring the change of storage environment. Smart storage technologies applied to fresh foods need to be highly efficient and nondestructive and need to be competitively priced. In this work, we have critically reviewed the principles, applications, and development trends of smart storage technologies.

  6. Technology transfer 1995

    Energy Technology Data Exchange (ETDEWEB)

    1995-01-01

    Technology Transfer 1995 is intended to inform the US industrial and academic sectors about the many opportunities they have to form partnerships with the US Department of Energy (DOE) for the mutual advantage of the individual institutions, DOE, and the nation as a whole. It also describes some of the growing number of remarkable achievements resulting from such partnerships. These partnership success stories offer ample evidence that Americans are learning how to work together to secure major benefits for the nation--by combining the technological, scientific, and human resources resident in national laboratories with those in industry and academia. The benefits include more and better jobs for Americans, improved productivity and global competitiveness for technology-based industries, and a more efficient government laboratory system.

  7. Principles for fostering the transdisciplinary development of assistive technologies.

    Science.gov (United States)

    Boger, Jennifer; Jackson, Piper; Mulvenna, Maurice; Sixsmith, Judith; Sixsmith, Andrew; Mihailidis, Alex; Kontos, Pia; Miller Polgar, Janice; Grigorovich, Alisa; Martin, Suzanne

    2017-07-01

    Developing useful and usable assistive technologies often presents complex (or "wicked") challenges that require input from multiple disciplines and sectors. Transdisciplinary collaboration can enable holistic understanding of challenges that may lead to innovative, impactful and transformative solutions. This paper presents generalised principles that are intended to foster transdisciplinary assistive technology development. The paper introduces the area of assistive technology design before discussing general aspects of transdisciplinary collaboration followed by an overview of relevant concepts, including approaches, methodologies and frameworks for conducting and evaluating transdisciplinary working and assistive technology design. The principles for transdisciplinary development of assistive technologies are presented and applied post hoc to the COACH project, an ambient-assisted living technology for guiding completion of activities of daily living by older adults with dementia as an illustrative example. Future work includes the refinement and validation of these principles through their application to real-world transdisciplinary assistive technology projects. Implications for rehabilitation Transdisciplinarity encourages a focus on real world 'wicked' problems. A transdisciplinary approach involves transcending disciplinary boundaries and collaborating with interprofessional and community partners (including the technology's intended users) on a shared problem. Transdisciplinarity fosters new ways of thinking about and doing research, development, and implementation, expanding the scope, applicability, and commercial viability of assistive technologies.

  8. Overcoming regulatory barriers: DOE environmental technology development program

    International Nuclear Information System (INIS)

    Kurtyka, B.M.; Clodfelter-Schumack, K.; Evans, T.T.

    1995-01-01

    The potential to improve environmental conditions via compliance or restoration is directly related to the ability to produce and apply innovative technological solutions. However, numerous organizations, including the US General Accounting Office (GAO), the EPA National Advisory Council for Environmental Policy and Technology (NACEPT), the DOE Environmental Management Advisory Board (EMAB), and the National Science and Technology Council (NSTC) have determined that significant regulatory barriers exist that inhibit the development and application of these technologies. They have noted the need for improved efforts in identifying and rectifying these barriers for the purpose of improving the technology development process, providing innovative alternatives, and enhancing the likelihood of technology acceptance by all. These barriers include, among others, regulator and user bias against ''unknown/unproven'' technologies; multi-level/multi-media permit disincentives; potential liability of developers and users for failed implementation; wrongly defined or inadequate data quality objectives: and lack of customer understanding and input. The ultimate goal of technology development is the utilization of technologies. This paper will present information on a number of regulatory barriers hindering DOE's environmental technology development program and describe DOE efforts to address these barriers

  9. Threshold evaluations of industrial conservation technologies run in ISTUM base case

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-20

    The results of threshold evaluations performed on several INDUS technologies which were competed with other new and conventional industrial technologies in the Industrial Sector Technology Use Model (ISTUM) developed by EEA are summarized. The ISTUM model is briefly described and includes the input technology categories and service sectors treated in the model, and the solution technique used. The input data specifications are summaried for the Industry Conservation Technologies run in the ISTUM base case. Included are listings of the technologies run in ISTUM, those not run in ISTUM, and a discussion of the absence of a retrofit algorithm in ISTUM and its resulting impact on conservation technologies. Also included is a discussion of the capital cost variability, maximum market fraction, size and load factors and data quality specifications for the conservation technologies in ISTUM. The results of the ISTUM base case run are presented, describing the important limitations and constraints of the base case run, the key assumptions inherent in the base case, and the summarized results of energy savings by year for different generic technology types. The technology characterization data developed for each INDUS technology run in the ISTUM base case are discussed in detail. The descriptions include the calculations and assumptions used in determining the service demand displacement, equipment cost, maximum market fraction, data quality, and size and load range for each technology.

  10. National Nuclear Technology Map Development

    International Nuclear Information System (INIS)

    Shin, J. I.; Lee, T. J.; Yoon, S. W.

    2005-03-01

    The objective of NuTRM is to prepare a plan of nuclear R and D and technological innovations which is very likely to make nuclear technology a promising power source for future national developments. The NuTRM finds out systematically the nuclear R and D vision and the high-value-added strategic technologies to be developed by the efficient cooperation of actors including government, industry, academy and research institute by 2020. In other words, NuTRM aims at a long-term strategic planning of nuclear R and D and technological innovation in order to promote the socio-economic contributions of nuclear science and technology for the nation's future competitiveness and sustainable development and to raise the global status of the Korean nuclear R and D and Industry

  11. SMD Technology Development Story for NASA Annual Technology report

    Science.gov (United States)

    Seablom, Michael S.

    2017-01-01

    The role of the Science Mission Directorate (SMD) is to enable NASA to achieve its science goals in the context of the Nation's science agenda. SMD's strategic decisions regarding future missions and scientific pursuits are guided by Agency goals, input from the science community-including the recommendations set forth in the National Research Council (NRC) decadal surveys-and a commitment to preserve a balanced program across the major science disciplines. Toward this end, each of the four SMD science divisions-Heliophysics, Earth Science, Planetary Science, and Astrophysics-develops fundamental science questions upon which to base future research and mission programs. Often the breakthrough science required to answer these questions requires significant technological innovation-e.g., instruments or platforms with capabilities beyond the current state of the art. SMD's targeted technology investments fill technology gaps, enabling NASA to build the challenging and complex missions that accomplish groundbreaking science.

  12. Technology Education Benefits from the Inclusion of Pre-Engineering Education

    Science.gov (United States)

    Rogers, Steve; Rogers, George E.

    2005-01-01

    Technology education is being taught today in almost every high school and middle school in America. Over 1000 technology education departments are now including pre-engineering education in their programs. According to these authors, the time has come for the profession to agree that including pre-engineering education in technology education…

  13. (Environmental technology)

    Energy Technology Data Exchange (ETDEWEB)

    Boston, H.L.

    1990-10-12

    The traveler participated in a conference on environmental technology in Paris, sponsored by the US Embassy-Paris, US Environmental Protection Agency (EPA), the French Environmental Ministry, and others. The traveler sat on a panel for environmental aspects of energy technology and made a presentation on the potential contributions of Oak Ridge National Laboratory (ORNL) to a planned French-American Environmental Technologies Institute in Chattanooga, Tennessee, and Evry, France. This institute would provide opportunities for international cooperation on environmental issues and technology transfer related to environmental protection, monitoring, and restoration at US Department of Energy (DOE) facilities. The traveler also attended the Fourth International Conference on Environmental Contamination in Barcelona. Conference topics included environmental chemistry, land disposal of wastes, treatment of toxic wastes, micropollutants, trace organics, artificial radionuclides in the environment, and the use biomonitoring and biosystems for environmental assessment. The traveler presented a paper on The Fate of Radionuclides in Sewage Sludge Applied to Land.'' Those findings corresponded well with results from studies addressing the fate of fallout radionuclides from the Chernobyl nuclear accident. There was an exchange of new information on a number of topics of interest to DOE waste management and environmental restoration needs.

  14. ExMC Technology Watch

    Science.gov (United States)

    Krihak, M.; Barr, Y.; Watkins, S.; Fung, P.; McGrath, T.; Baumann, D.

    2012-01-01

    The Technology Watch (Tech Watch) project is a NASA endeavor conducted under the Human Research Program's (HRP) Exploration Medical Capability (ExMC) element, and focusing on ExMC technology gaps. The project involves several NASA centers, including the Johnson Space Center (JSC), Glenn Research Center (GRC), Ames Research Center (ARC), and the Langley Research Center (LaRC). The objective of Tech Watch is to identify emerging, high-impact technologies that augment current NASA HRP technology development efforts. Identifying such technologies accelerates the development of medical care and research capabilities for the mitigation of potential health issues encountered during human space exploration missions. The aim of this process is to leverage technologies developed by academia, industry and other government agencies and to identify the effective utilization of NASA resources to maximize the HRP return on investment. The establishment of collaborations with these entities is beneficial to technology development, assessment and/or insertion and further NASA's goal to provide a safe and healthy environment for human exploration. In 2011, the major focus areas for Tech Watch included information dissemination, education outreach and public accessibility to technology gaps and gap reports. The dissemination of information was accomplished through site visits to research laboratories and/or companies, and participation at select conferences where Tech Watch objectives and technology gaps were presented. Presentation of such material provided researchers with insights on NASA ExMC needs for space exploration and an opportunity to discuss potential areas of common interest. The second focus area, education outreach, was accomplished via two mechanisms. First, several senior student projects, each related to an ExMC technology gap, were sponsored by the various NASA centers. These projects presented ExMC related technology problems firsthand to collegiate laboratories

  15. Electric technology in the food service industry; Les technologies electriques dans les services alimentaires

    Energy Technology Data Exchange (ETDEWEB)

    Labonte, A. [Hydro-Quebec, Montreal, PQ (Canada)

    1997-04-01

    Many innovative technologies in the food service industry have been made through the use of electricity as a source of energy. Electricity made it possible to improve the productivity and profitability of the food industry. Some of these technologies include: (1) cooking by induction, which is based on the principle of magnetic fields, (2) combined convection ovens which accelerate thermal exchange, and (3) electric fryers. The advantages of each technology were described. The environmental advantage of using electricity as an energy source in the food service industry was also discussed.

  16. The Tipping Points of Technology Development

    Directory of Open Access Journals (Sweden)

    Tauno Kekäle

    2014-07-01

    Full Text Available The tipping point, the decisive point in time in the competition between old and new, is an interesting phenomenon in physics of today. This aspect in technology acceptance is connected to many business decisions such as technology investments, product releases, resource allocation, sales forecasts and, ultimately, affects the profitability and even survival of a company. The tipping point itself is based on many stochastic and dynamic variables, and the process may at least partly be described as path-dependent. This paper analyses the tipping point from three aspects: (1 product performance, (2 features of the market and infrastructure (including related technologies and human network externalities, and (3 actions of the incumbents (including customer lock-in, systems lock-in, and sustaining innovation. The paper is based on the Bass s-curve idea and the technology trajectory concept proposed by Dosi. Three illustrative cases are presented to make the point of the multiple factors affecting technology acceptance and, thus, the tipping point. The paper also suggests outlines for further research in field of computer simulation.

  17. Detection and control of combustion instability based on the concept of dynamical system theory

    Science.gov (United States)

    Gotoda, Hiroshi; Shinoda, Yuta; Kobayashi, Masaki; Okuno, Yuta; Tachibana, Shigeru

    2014-02-01

    We propose an online method of detecting combustion instability based on the concept of dynamical system theory, including the characterization of the dynamic behavior of combustion instability. As an important case study relevant to combustion instability encountered in fundamental and practical combustion systems, we deal with the combustion dynamics close to lean blowout (LBO) in a premixed gas-turbine model combustor. The relatively regular pressure fluctuations generated by thermoacoustic oscillations transit to low-dimensional intermittent chaos owing to the intermittent appearance of burst with decreasing equivalence ratio. The translation error, which is characterized by quantifying the degree of parallelism of trajectories in the phase space, can be used as a control variable to prevent LBO.

  18. Detection and control of combustion instability based on the concept of dynamical system theory.

    Science.gov (United States)

    Gotoda, Hiroshi; Shinoda, Yuta; Kobayashi, Masaki; Okuno, Yuta; Tachibana, Shigeru

    2014-02-01

    We propose an online method of detecting combustion instability based on the concept of dynamical system theory, including the characterization of the dynamic behavior of combustion instability. As an important case study relevant to combustion instability encountered in fundamental and practical combustion systems, we deal with the combustion dynamics close to lean blowout (LBO) in a premixed gas-turbine model combustor. The relatively regular pressure fluctuations generated by thermoacoustic oscillations transit to low-dimensional intermittent chaos owing to the intermittent appearance of burst with decreasing equivalence ratio. The translation error, which is characterized by quantifying the degree of parallelism of trajectories in the phase space, can be used as a control variable to prevent LBO.

  19. Older Adults' Acceptance of Information Technology

    Science.gov (United States)

    Wang, Lin; Rau, Pei-Luen Patrick; Salvendy, Gavriel

    2011-01-01

    This study investigated variables contributing to older adults' information technology acceptance through a survey, which was used to find factors explaining and predicting older adults' information technology acceptance behaviors. Four factors, including needs satisfaction, perceived usability, support availability, and public acceptance, were…

  20. Tribology: Friction, lubrication, and wear technology

    Science.gov (United States)

    Blau, Peter J.

    1993-01-01

    The topics are presented in viewgraph form and include the following: introduction and definitions of terms; friction concepts; lubrication technology concepts; wear technology concepts; and tribological transitions. This document is designed for educators who seek to teach these concepts to their students.